Neurodegenerative diseases are prevalent conditions that greatly impact human health.These diseases are primarily characterized by the progressive loss and eventual death of neuronal function,although the precise mech...Neurodegenerative diseases are prevalent conditions that greatly impact human health.These diseases are primarily characterized by the progressive loss and eventual death of neuronal function,although the precise mechanisms underlying these processes remain incompletely understood.Iron is an essential trace element in the human body,playing a crucial role in various biological processes.The maintenance of iron homeostasis relies on the body's intricate and nuanced regulatory mechanisms.In recent years,considerable attention has been directed toward the relationship between dysregulated iron homeostasis and neurodegenerative diseases.The regulation of iron homeostasis within cells is crucial for maintaining proper nervous system function.Research has already revealed that disruptions in iron homeostasis may lead to ferroptosis and oxidative stress,which,in turn,can impact neuronal health and contribute to the development of neurodegenerative diseases.This article primarily explores the intimate relationship between iron homeostasis and neurodegenerative diseases,aiming to provide novel insights and strategies for treating these debilitating conditions.展开更多
A highly sensitive amperometric sulfadiazine sensor fabricated by electrochemical deposition of poly(cobalt tetraaminophthalocyanine) (poly(Co II TAPc)) on the surface of a multi-walled carbon nanotubes-Nafion (MWCNTs...A highly sensitive amperometric sulfadiazine sensor fabricated by electrochemical deposition of poly(cobalt tetraaminophthalocyanine) (poly(Co II TAPc)) on the surface of a multi-walled carbon nanotubes-Nafion (MWCNTs-Nafion) modified electrode is described.This electrode showed a very attractive performance by combining the advantages of Co II TAPc,MWCNTs,and Nafion.Compared with the bare glassy carbon electrode (GCE) and the MWCNTs-Nafion modified electrode,the electrocatalytic activity of poly(Co II TAPc)-coated MWCNTs-Nafion GCE generated greatly improved electrochemical detections toward sulfadiazine including low oxidation potential,high current responses,and good anti-fouling performance.The oxidation peak currents of sulfadiazine obtained on the new modified electrode increased linearly while increasing the concentration of sulfadiazine from 0.5 to 43.5 μmol/L with the detection limit of 0.17 μmol/L.展开更多
In the present work, a novel analytical method was proposed for the determination of toluene diisocyanate （TDI） in syntheticrubber track by ion chromatography （IC） coupled with an ultraviolet detector setting at 2...In the present work, a novel analytical method was proposed for the determination of toluene diisocyanate （TDI） in syntheticrubber track by ion chromatography （IC） coupled with an ultraviolet detector setting at 212 nm. TDI can be hydrolyzed to toluene diamine （TDA） which can be separated by cation-exchange IC easily. The optimum IC separation was performed on an IonPac CS12A column （150 mm ×4.0 mm） using 20 mmol L^-1 sodium sulfate, 10 mmol L^-1 sulfuric acid and 10% acetonitrile as eluent. It was found that a higher signal response of TDA could be obtained under alkaline condition. A suppressor was used to change the acidic eluent into alkaline one. 0.8 mol L^-1 potassium hydroxide was chosen as the optimum regeneration eluent. With the added suppressor and regenerant, signal response was magnified by about 16 times and lower limit of detection （LOD, 0.13 μg L^-1） was obtained. Within-day relative standard deviation （R.S.D.） was less than 3.6%. The recoveries of TDI spiked in synthetic-rubber track samoles were 96.4-110.6%.展开更多
The production of safety food is an important foundation for establishing a Food Quality Safety Management System. The investigation focused on 11 kinds of safety food produced by 11 agricultural enterprises in Jiaxin...The production of safety food is an important foundation for establishing a Food Quality Safety Management System. The investigation focused on 11 kinds of safety food produced by 11 agricultural enterprises in Jiaxing, a part of the Yangtze River delta region in China. The economic performances of safety foods were also analyzed. The analysis showed that safety food production input was more than that of normal food and had different cost items compared to normal food. The rate of cost overflow was lower than the rate of comparative returns, resulting in the economic performance of safety food being higher than that of normal food. However, there were some problems, such as high quality without high prices. In the production of safety food, we will mainly pay attention to them.展开更多
Objective The study of medicine formulas is a core component of traditional Chinese medicine(TCM),yet traditional learning methods often lack interactivity and contextual understanding,making it challenging for beginn...Objective The study of medicine formulas is a core component of traditional Chinese medicine(TCM),yet traditional learning methods often lack interactivity and contextual understanding,making it challenging for beginners to grasp the intricate composition rules of formulas.To address this gap,we introduce Formula-S,a situated visualization method for TCM formula learning in augmented reality(AR)and evaluate its performance.This study aims to evaluate the effectiveness of Formula-S in enhancing TCM formula learning for beginners by comparing it with traditional text-based formula learning and web-based visualization.Methods Formula-S is an interactive AR tool designed for TCM formula learning,featuring three modes(3D,Web,and Table).The dataset included TCM formulas and herb properties extracted from authoritative references,including textbook and the SymMap database.In Formula-S,the hierarchical visualization of the formulas as herbal medicine compositions,is linked to the multidimensional herb attribute visualization and embedded in the real world,where real herb samples are presented.To evaluate its effectiveness,a controlled study(n=30)was conducted.Participants who had no formal TCM knowledge were tasked with herbal medicine identification,formula composition,and recognition.In the study,participants interacted with the AR tool through HoloLens 2.Data were collected on both task performance(accuracy and response time)and user experience,with a focus on task efficiency,accuracy,and user preference across the different learning modes.Results The situated visualization method of Formula-S had comparable accuracy to other methods but shorter response time for herbal formula learning tasks.Regarding user experience,our new approach demonstrated the highest system usability and lowest task load,effectively reducing cognitive load and allowing users to complete tasks with greater ease and efficiency.Participants reported that Formula-S enhanced their learning experience through its intuitive interface and immersive AR environment,suggesting this approach offers usability advantages for TCM education.Conclusions The situated visualization method in Formula-S offers more efficient and accurate searching capabilities compared to traditional and web-based methods.Additionally,it provides superior contextual understanding of TCM formulas,making it a promising new solution for TCM learning.展开更多
We developed a pulsar search pipeline based on PulsaR Exploration and Search TOolkit(PRESTO).This pipeline simply runs dedispersion,Fast Fourier Transform(FFT)and acceleration search in process-level parallel to short...We developed a pulsar search pipeline based on PulsaR Exploration and Search TOolkit(PRESTO).This pipeline simply runs dedispersion,Fast Fourier Transform(FFT)and acceleration search in process-level parallel to shorten the processing time.With two parallel strategies,the pipeline can highly shorten the processing time in both normal searches and acceleration searches.This pipeline was first tested with Parkes Multibeam Pulsar Survery(PMPS)data and discovered two new faint pulsars.Then,it was successfully applied in processing the Five-hundred-meter Aperture Spherical radio Telescope(FAST)drift scan data with tens of new pulsar discoveries up to now.The pipeline is only CPU-based and can be easily and quickly deployed in computing nodes for testing purposes or data processing.展开更多
This paper reports on the time and frequency standard system for the Five-hundred meter Aperture Spherical radio Telescope(FAST),including the system design,stability measurements and pulsar timing observations.The st...This paper reports on the time and frequency standard system for the Five-hundred meter Aperture Spherical radio Telescope(FAST),including the system design,stability measurements and pulsar timing observations.The stability and drift rate of the frequency standard are calculated using 1-year monitoring data.The UTC-NIM Disciplined Oscillator(NIMDO)system improves the system time accuracy and stability to the level of 5 ns.Pulsar timing observations were carried out for several months.The weighted RMS of timing residuals reaches the level of less than 3.0μs.展开更多
We present a pilot HI survey of 17 Planck Galactic Cold Clumps(PGCCs)with the Five-hundred-meter Aperture Spherical radio Telescope(FAST).HI Narrow Self-Absorption(HINSA)is an effective method to detect cold HI being ...We present a pilot HI survey of 17 Planck Galactic Cold Clumps(PGCCs)with the Five-hundred-meter Aperture Spherical radio Telescope(FAST).HI Narrow Self-Absorption(HINSA)is an effective method to detect cold HI being mixed with molecular hydrogen H2 and improves our understanding of the atomic to molecular transition in the interstellar medium.HINSA was found in 58%PGCCs that we observed.The column density of HINSA was found to have an intermediate correlation with that of 13CO,following log(N(HINSA))=(0.52±0.26)log(N13CO)+(10±4.1).HI abundance relative to total hydrogen[HI]/[H]has an average value of 4.4×10-3,which is about 2.8 times of the average value of previous HINSA surveys toward molecular clouds.For clouds with total column density NH>5×1020 cm-2,an inverse correlation between HINSA abundance and total hydrogen column density is found,confirming the depletion of cold HI gas during molecular gas formation in more massive clouds.Nonthermal line width of 13CO is about 0-0.5 kms-1 larger than that of HINSA.One possible explanation of narrower non-thermal width of HINSA is that HINSA region is smaller than that of 13CO.Based on an analytic model of H2 formation and H2 dissociation by cosmic ray,we found the cloud ages to be within 106.7-107.0 yr for five sources.展开更多
The family Hepeviridae has seen an explosive expansion in its host range in recent years,yet the evolutionary trajectory of this zoonotic pathogen remains largely unknown.The emergence of rat hepatitis E virus(HEV)has...The family Hepeviridae has seen an explosive expansion in its host range in recent years,yet the evolutionary trajectory of this zoonotic pathogen remains largely unknown.The emergence of rat hepatitis E virus(HEV)has introduced a new public health threat due to its potential for zoonotic transmission.This study investigated2?464 wild small mammals spanning four animal orders,eight families,21 genera,and 37 species in Yunnan Province,China.Using broadly reactive reverse transcription-polymerase chain reaction(RT-PCR),we systematically screened the presence and prevalence of Orthohepevirus and identified 192 positive specimens from10 species,corresponding to an overall detection rate of7.79%.Next-generation sequencing enabled the recovery of 24 full-length genomic sequences from eight host species,including Bandicota bengalensis,Eothenomys eleusis,and Episoriculus caudatus,representing newly reported host species for Orthohepevirus strains.Phylogenetic and sequence analyses revealed extensive genetic diversity within orthohepeviruses infecting rodents and shrews.Notably,among the identified strains,20 were classified as Rocahepevirus ratti C1,two as C3,and one as Rocahepevirus eothenomi,while the remaining strain exhibited significant divergence,precluding classification.Evolutionary analyses highlighted close associations between orthohepeviruses and their respective host taxa,with distinct phylogenetic clustering patterns observed across different host orders.These findings emphasize the critical roles of co-speciation and cross-species transmission in shaping the evolutionary trajectories of the genera Paslahepevirus and Rocahepevirus.展开更多
FeSe is an Fe-based paramagnetic superconductor with the simplest structure.The competition between the Néel and stripe magnetic orders is believed to be one of the reasons for the absence of magnetic orders in F...FeSe is an Fe-based paramagnetic superconductor with the simplest structure.The competition between the Néel and stripe magnetic orders is believed to be one of the reasons for the absence of magnetic orders in FeSe.FeSe is recognized as a prototypical platform for competing magnetic interactions,including Néel,stripe,and staggered antiferromagnetic coupling.However,the correlations between these magnetic orders and how they change with varying environmental conditions require further study.Here,we calculated the magnetic order of monolayer FeSe in three diferent environments:pure one,with slight lattice distortion,and on SrTiO_(3) substrate,by frst principles calculations.We fnd that in the calculated dispersion relation E(q)between the spin spiral energy E and spin spiral vector q of the monolayer FeSe structure,the stripe magnetic order M(π/2,π/2)has the lowest energy,and there is a fat E(q)between the wave vector X(π/2,0)and Néel magnetic order 2X(π,0),which are the degenerate E(q)states.The ground state of M and the highest density of states around 2X may be the reason for the competition of two magnetic orders.The slight lattice distortion does not alter the magnetic properties of monolayer FeSe.When monolayer FeSe is attached to the SrTiO_(3)substrate,the degenerate E(q)is still retained;meanwhile,the energy of the 2X(π,0)state is closer to the M state,which may be one of the reasons for the increase of superconducting temperature in FeSe/SrTiO_(3).展开更多
The Twain-Hu Basin(THB),located in Central China,serves as a key juncture where the northerly“polluted”airflows of the East Asian winter monsoon meet the southerly warm and humid airflows.Using the T-PCA(T-mode Prin...The Twain-Hu Basin(THB),located in Central China,serves as a key juncture where the northerly“polluted”airflows of the East Asian winter monsoon meet the southerly warm and humid airflows.Using the T-PCA(T-mode Principal Component Analysis)objective synoptic pattern classification,Flexible Particle-Weather Research and Forecasting(FLEXPARTWRF)model,and Random Forest model,we investigate the influences of synoptic circulations on regional transport,local accumulation,and chemical transformation of PM_(2.5)during heavy air pollution over the THB in January of 2015-2022.The results show that the transport-type synoptic pattern accounts for 65.16%of heavy PM_(2.5)pollution,indicating that regional transport of PM_(2.5)dominates the THB’s heavy air pollution.The PM_(2.5)/CO ratio is higher in the transport-type pattern and positively correlated with PM_(2.5)concentrations,reflecting a higher efficiency of chemical transformation to secondary PM_(2.5)in transport-type pollution compared with the accumulation-type pollution.Transport-type heavy PM_(2.5)pollution is predominantly influenced by upstream anomalous northerly and easterly airflows at the bottom of the high-pressure system,converging with the southern wind in the receptor area over the THB.Accumulation-type heavy pollution exhibits weak wind anomalies in central and eastern China under the control of a uniform pressure field.Furthermore,thermally-induced vertical circulations with sinking airflows in the middle and lower troposphere suppress the vertical air pollutant dispersions.The relative contributions of atmospheric factors for transport-type PM_(2.5)heavy pollution events are 38.0%for dynamical driver,26.8%for thermal driver,and 35.1%for chemical transformation,while in accumulation-type,the contribution rates are 33.9%,36.3%,and 29.7%,respectively.This study elucidates the influences of synoptic patterns on regional transport,local accumulation,and chemical transformation of PM_(2.5)for heavy air pollution,with implications for understanding changes of air quality in the receptor region of regional transport.展开更多
BACKGROUND In recent years,endoscopic resection(ER)has been employed for the excision of submucosal tumors(SMTs).Nonetheless,ER in the duodenum is linked to ele-vated risks of both immediate and delayed hemorrhagic co...BACKGROUND In recent years,endoscopic resection(ER)has been employed for the excision of submucosal tumors(SMTs).Nonetheless,ER in the duodenum is linked to ele-vated risks of both immediate and delayed hemorrhagic complications and perforations.Satisfactory suturing is crucial for reducing the occurrence of complications.AIM To establish a clinical score model for supporting suture decision-making of duodenal SMTs.METHODS This study included 137 individuals diagnosed with duodenal SMTs who under-went ER.Participants were evenly divided into two groups:A training cohort(TC)comprising 95 cases and an internal validation cohort(VC)with 42 cases.Subsequently,a scoring system was formulated utilizing multivariate logistic regression analysis within the TC,which was then subjected to evaluation in the VC.RESULTS The clinical scoring system incorporated two key factors:Extraluminal growth,which was assigned 2 points,and endoscopic full-thickness resection,which was given 3 points.This model demonstrated strong predictive accuracy,as evidenced by the area under the receiver operating characteristic curve of 0.900(95%confidence interval:0.823-0.976).Additionally,the model’s goodness-of-fit was validated by the Hosmer-Lemeshow test(P=0.404).The probability of purse-string suturing in low(score 0-2)and high(score>3)categories were 3.0%and 64.3%in the TC,and 6.1%and 88.9%in the VC,respectively.CONCLUSION This scoring system may function as a beneficial instrumentality for medical practitioners,facilitating the decision-making process concerning suture techniques in the context of duodenal SMTs.展开更多
基金supported in part by the National Natural Science Foundation of China,No.82371153(to YS)the Natural Science Foundation of Shandong Province,Nos.ZR2021MH378,ZR2022QH073(to LC)+1 种基金the Shandong Society of Geriatric Science and Technology Project,No.LKJGG2021Z020(to YS)the Yantai Science and Technology Innovation Development Project,Nos.2022YD009,2023YD050。
文摘Neurodegenerative diseases are prevalent conditions that greatly impact human health.These diseases are primarily characterized by the progressive loss and eventual death of neuronal function,although the precise mechanisms underlying these processes remain incompletely understood.Iron is an essential trace element in the human body,playing a crucial role in various biological processes.The maintenance of iron homeostasis relies on the body's intricate and nuanced regulatory mechanisms.In recent years,considerable attention has been directed toward the relationship between dysregulated iron homeostasis and neurodegenerative diseases.The regulation of iron homeostasis within cells is crucial for maintaining proper nervous system function.Research has already revealed that disruptions in iron homeostasis may lead to ferroptosis and oxidative stress,which,in turn,can impact neuronal health and contribute to the development of neurodegenerative diseases.This article primarily explores the intimate relationship between iron homeostasis and neurodegenerative diseases,aiming to provide novel insights and strategies for treating these debilitating conditions.
基金Project supported by the National Natural Science Foundation of China (Nos.20803067 and 20911140271)the Qianjiang Talents Project of the Technology Office of Zhejiang Province (No.2009R10029)the Natural Science Foundation of Zhejiang Province (No.Y5110054),China
文摘A highly sensitive amperometric sulfadiazine sensor fabricated by electrochemical deposition of poly(cobalt tetraaminophthalocyanine) (poly(Co II TAPc)) on the surface of a multi-walled carbon nanotubes-Nafion (MWCNTs-Nafion) modified electrode is described.This electrode showed a very attractive performance by combining the advantages of Co II TAPc,MWCNTs,and Nafion.Compared with the bare glassy carbon electrode (GCE) and the MWCNTs-Nafion modified electrode,the electrocatalytic activity of poly(Co II TAPc)-coated MWCNTs-Nafion GCE generated greatly improved electrochemical detections toward sulfadiazine including low oxidation potential,high current responses,and good anti-fouling performance.The oxidation peak currents of sulfadiazine obtained on the new modified electrode increased linearly while increasing the concentration of sulfadiazine from 0.5 to 43.5 μmol/L with the detection limit of 0.17 μmol/L.
基金supported by the National Natural Science Foundation of China(No.20775070)Zhejiang Provincial Natural Science Foundation of China(No.Y507252).
文摘In the present work, a novel analytical method was proposed for the determination of toluene diisocyanate （TDI） in syntheticrubber track by ion chromatography （IC） coupled with an ultraviolet detector setting at 212 nm. TDI can be hydrolyzed to toluene diamine （TDA） which can be separated by cation-exchange IC easily. The optimum IC separation was performed on an IonPac CS12A column （150 mm ×4.0 mm） using 20 mmol L^-1 sodium sulfate, 10 mmol L^-1 sulfuric acid and 10% acetonitrile as eluent. It was found that a higher signal response of TDA could be obtained under alkaline condition. A suppressor was used to change the acidic eluent into alkaline one. 0.8 mol L^-1 potassium hydroxide was chosen as the optimum regeneration eluent. With the added suppressor and regenerant, signal response was magnified by about 16 times and lower limit of detection （LOD, 0.13 μg L^-1） was obtained. Within-day relative standard deviation （R.S.D.） was less than 3.6%. The recoveries of TDI spiked in synthetic-rubber track samoles were 96.4-110.6%.
文摘The production of safety food is an important foundation for establishing a Food Quality Safety Management System. The investigation focused on 11 kinds of safety food produced by 11 agricultural enterprises in Jiaxing, a part of the Yangtze River delta region in China. The economic performances of safety foods were also analyzed. The analysis showed that safety food production input was more than that of normal food and had different cost items compared to normal food. The rate of cost overflow was lower than the rate of comparative returns, resulting in the economic performance of safety food being higher than that of normal food. However, there were some problems, such as high quality without high prices. In the production of safety food, we will mainly pay attention to them.
文摘Objective The study of medicine formulas is a core component of traditional Chinese medicine(TCM),yet traditional learning methods often lack interactivity and contextual understanding,making it challenging for beginners to grasp the intricate composition rules of formulas.To address this gap,we introduce Formula-S,a situated visualization method for TCM formula learning in augmented reality(AR)and evaluate its performance.This study aims to evaluate the effectiveness of Formula-S in enhancing TCM formula learning for beginners by comparing it with traditional text-based formula learning and web-based visualization.Methods Formula-S is an interactive AR tool designed for TCM formula learning,featuring three modes(3D,Web,and Table).The dataset included TCM formulas and herb properties extracted from authoritative references,including textbook and the SymMap database.In Formula-S,the hierarchical visualization of the formulas as herbal medicine compositions,is linked to the multidimensional herb attribute visualization and embedded in the real world,where real herb samples are presented.To evaluate its effectiveness,a controlled study(n=30)was conducted.Participants who had no formal TCM knowledge were tasked with herbal medicine identification,formula composition,and recognition.In the study,participants interacted with the AR tool through HoloLens 2.Data were collected on both task performance(accuracy and response time)and user experience,with a focus on task efficiency,accuracy,and user preference across the different learning modes.Results The situated visualization method of Formula-S had comparable accuracy to other methods but shorter response time for herbal formula learning tasks.Regarding user experience,our new approach demonstrated the highest system usability and lowest task load,effectively reducing cognitive load and allowing users to complete tasks with greater ease and efficiency.Participants reported that Formula-S enhanced their learning experience through its intuitive interface and immersive AR environment,suggesting this approach offers usability advantages for TCM education.Conclusions The situated visualization method in Formula-S offers more efficient and accurate searching capabilities compared to traditional and web-based methods.Additionally,it provides superior contextual understanding of TCM formulas,making it a promising new solution for TCM learning.
基金supported by the National Key R&D Program of China(2017YFA0402600)State Key DevelopmentProgram for Basic Research(2015CB857100)+4 种基金National Basic Research Program of China(973 program,No.2015CB857101)National Natural Science Foundation of China(Grant Nos.11703047,11773041,U1631132and U1831131)supported by the CAS“Light of West China”Programby the CAS Key Laboratory of FAST,National Astronomical Observatories,Chinese Academy of Sciencessupported in part by the Youth Innovation Promotion Association of CAS(id.2018075)。
文摘We developed a pulsar search pipeline based on PulsaR Exploration and Search TOolkit(PRESTO).This pipeline simply runs dedispersion,Fast Fourier Transform(FFT)and acceleration search in process-level parallel to shorten the processing time.With two parallel strategies,the pipeline can highly shorten the processing time in both normal searches and acceleration searches.This pipeline was first tested with Parkes Multibeam Pulsar Survery(PMPS)data and discovered two new faint pulsars.Then,it was successfully applied in processing the Five-hundred-meter Aperture Spherical radio Telescope(FAST)drift scan data with tens of new pulsar discoveries up to now.The pipeline is only CPU-based and can be easily and quickly deployed in computing nodes for testing purposes or data processing.
基金supported by the Joint Research Fund in Astronomy(Grant Nos.U1931129,U1631115 and U1831117)under cooperative agreement between NSFC and Chinese Academy of Sciences(CAS)NSFC-STINT Grant 11611130023(CH2015-6360)the National Natural Science Foundation of China(NSFC,Grant No.11403054)
文摘This paper reports on the time and frequency standard system for the Five-hundred meter Aperture Spherical radio Telescope(FAST),including the system design,stability measurements and pulsar timing observations.The stability and drift rate of the frequency standard are calculated using 1-year monitoring data.The UTC-NIM Disciplined Oscillator(NIMDO)system improves the system time accuracy and stability to the level of 5 ns.Pulsar timing observations were carried out for several months.The weighted RMS of timing residuals reaches the level of less than 3.0μs.
基金supported by the National Key R&D Program of China(2017YFA0402600 and 2016YFA0400702)the National Natural Science Foundation of China(Grant Nos.11988101,11803051,11725313 and 11721303)+3 种基金CAS International Partnership Program(114A11KYSB20160008)CAS“Light of West China”ProgramCAS Interdisciplinary Innovation Team and Young Researcher Grant of National Astronomical Observatoriessupported in part by the Youth Innovation Promotion Association of CAS(No.2018075)
文摘We present a pilot HI survey of 17 Planck Galactic Cold Clumps(PGCCs)with the Five-hundred-meter Aperture Spherical radio Telescope(FAST).HI Narrow Self-Absorption(HINSA)is an effective method to detect cold HI being mixed with molecular hydrogen H2 and improves our understanding of the atomic to molecular transition in the interstellar medium.HINSA was found in 58%PGCCs that we observed.The column density of HINSA was found to have an intermediate correlation with that of 13CO,following log(N(HINSA))=(0.52±0.26)log(N13CO)+(10±4.1).HI abundance relative to total hydrogen[HI]/[H]has an average value of 4.4×10-3,which is about 2.8 times of the average value of previous HINSA surveys toward molecular clouds.For clouds with total column density NH>5×1020 cm-2,an inverse correlation between HINSA abundance and total hydrogen column density is found,confirming the depletion of cold HI gas during molecular gas formation in more massive clouds.Nonthermal line width of 13CO is about 0-0.5 kms-1 larger than that of HINSA.One possible explanation of narrower non-thermal width of HINSA is that HINSA region is smaller than that of 13CO.Based on an analytic model of H2 formation and H2 dissociation by cosmic ray,we found the cloud ages to be within 106.7-107.0 yr for five sources.
基金supported by the National Natural Science Foundation of China (U2002218,81874274)Yunnan Health Training Project of High Level Talents (L-2017027)+3 种基金Project of Cross-border Control and Quarantine Innovation Group of Zoonosis of Dali University (ZKPY2019302)to Y.Z.ZOpen Project of Yunnan Key Laboratory of Biodiversity Information (BIKF22-02)Youth Innovation Promotion Association of the Chinese Academy of SciencesYunnan Revitalization Talent Support Program Young Talent Project to X.L.Y。
文摘The family Hepeviridae has seen an explosive expansion in its host range in recent years,yet the evolutionary trajectory of this zoonotic pathogen remains largely unknown.The emergence of rat hepatitis E virus(HEV)has introduced a new public health threat due to its potential for zoonotic transmission.This study investigated2?464 wild small mammals spanning four animal orders,eight families,21 genera,and 37 species in Yunnan Province,China.Using broadly reactive reverse transcription-polymerase chain reaction(RT-PCR),we systematically screened the presence and prevalence of Orthohepevirus and identified 192 positive specimens from10 species,corresponding to an overall detection rate of7.79%.Next-generation sequencing enabled the recovery of 24 full-length genomic sequences from eight host species,including Bandicota bengalensis,Eothenomys eleusis,and Episoriculus caudatus,representing newly reported host species for Orthohepevirus strains.Phylogenetic and sequence analyses revealed extensive genetic diversity within orthohepeviruses infecting rodents and shrews.Notably,among the identified strains,20 were classified as Rocahepevirus ratti C1,two as C3,and one as Rocahepevirus eothenomi,while the remaining strain exhibited significant divergence,precluding classification.Evolutionary analyses highlighted close associations between orthohepeviruses and their respective host taxa,with distinct phylogenetic clustering patterns observed across different host orders.These findings emphasize the critical roles of co-speciation and cross-species transmission in shaping the evolutionary trajectories of the genera Paslahepevirus and Rocahepevirus.
基金supported by the National Natural Science Foundation of China(Grant Nos.11204131 and 11974181)。
文摘FeSe is an Fe-based paramagnetic superconductor with the simplest structure.The competition between the Néel and stripe magnetic orders is believed to be one of the reasons for the absence of magnetic orders in FeSe.FeSe is recognized as a prototypical platform for competing magnetic interactions,including Néel,stripe,and staggered antiferromagnetic coupling.However,the correlations between these magnetic orders and how they change with varying environmental conditions require further study.Here,we calculated the magnetic order of monolayer FeSe in three diferent environments:pure one,with slight lattice distortion,and on SrTiO_(3) substrate,by frst principles calculations.We fnd that in the calculated dispersion relation E(q)between the spin spiral energy E and spin spiral vector q of the monolayer FeSe structure,the stripe magnetic order M(π/2,π/2)has the lowest energy,and there is a fat E(q)between the wave vector X(π/2,0)and Néel magnetic order 2X(π,0),which are the degenerate E(q)states.The ground state of M and the highest density of states around 2X may be the reason for the competition of two magnetic orders.The slight lattice distortion does not alter the magnetic properties of monolayer FeSe.When monolayer FeSe is attached to the SrTiO_(3)substrate,the degenerate E(q)is still retained;meanwhile,the energy of the 2X(π,0)state is closer to the M state,which may be one of the reasons for the increase of superconducting temperature in FeSe/SrTiO_(3).
基金supported by the National Natural Science Foundation of China(Nos.42075186 and 41830965).
文摘The Twain-Hu Basin(THB),located in Central China,serves as a key juncture where the northerly“polluted”airflows of the East Asian winter monsoon meet the southerly warm and humid airflows.Using the T-PCA(T-mode Principal Component Analysis)objective synoptic pattern classification,Flexible Particle-Weather Research and Forecasting(FLEXPARTWRF)model,and Random Forest model,we investigate the influences of synoptic circulations on regional transport,local accumulation,and chemical transformation of PM_(2.5)during heavy air pollution over the THB in January of 2015-2022.The results show that the transport-type synoptic pattern accounts for 65.16%of heavy PM_(2.5)pollution,indicating that regional transport of PM_(2.5)dominates the THB’s heavy air pollution.The PM_(2.5)/CO ratio is higher in the transport-type pattern and positively correlated with PM_(2.5)concentrations,reflecting a higher efficiency of chemical transformation to secondary PM_(2.5)in transport-type pollution compared with the accumulation-type pollution.Transport-type heavy PM_(2.5)pollution is predominantly influenced by upstream anomalous northerly and easterly airflows at the bottom of the high-pressure system,converging with the southern wind in the receptor area over the THB.Accumulation-type heavy pollution exhibits weak wind anomalies in central and eastern China under the control of a uniform pressure field.Furthermore,thermally-induced vertical circulations with sinking airflows in the middle and lower troposphere suppress the vertical air pollutant dispersions.The relative contributions of atmospheric factors for transport-type PM_(2.5)heavy pollution events are 38.0%for dynamical driver,26.8%for thermal driver,and 35.1%for chemical transformation,while in accumulation-type,the contribution rates are 33.9%,36.3%,and 29.7%,respectively.This study elucidates the influences of synoptic patterns on regional transport,local accumulation,and chemical transformation of PM_(2.5)for heavy air pollution,with implications for understanding changes of air quality in the receptor region of regional transport.
基金Supported by National Natural Science Foundation of China,No.82170555Shanghai Academic/Technology Research Leader,No.22XD1422400+2 种基金Shanghai“Rising Stars of Medical Talent”Youth Development Program,No.20224Z0005the 74th General Support of China Postdoctoral Science Foundation,No.2023M740675Outstanding Resident Clinical Postdoctoral Program of Zhongshan Hospital Affiliated to Fudan University.
文摘BACKGROUND In recent years,endoscopic resection(ER)has been employed for the excision of submucosal tumors(SMTs).Nonetheless,ER in the duodenum is linked to ele-vated risks of both immediate and delayed hemorrhagic complications and perforations.Satisfactory suturing is crucial for reducing the occurrence of complications.AIM To establish a clinical score model for supporting suture decision-making of duodenal SMTs.METHODS This study included 137 individuals diagnosed with duodenal SMTs who under-went ER.Participants were evenly divided into two groups:A training cohort(TC)comprising 95 cases and an internal validation cohort(VC)with 42 cases.Subsequently,a scoring system was formulated utilizing multivariate logistic regression analysis within the TC,which was then subjected to evaluation in the VC.RESULTS The clinical scoring system incorporated two key factors:Extraluminal growth,which was assigned 2 points,and endoscopic full-thickness resection,which was given 3 points.This model demonstrated strong predictive accuracy,as evidenced by the area under the receiver operating characteristic curve of 0.900(95%confidence interval:0.823-0.976).Additionally,the model’s goodness-of-fit was validated by the Hosmer-Lemeshow test(P=0.404).The probability of purse-string suturing in low(score 0-2)and high(score>3)categories were 3.0%and 64.3%in the TC,and 6.1%and 88.9%in the VC,respectively.CONCLUSION This scoring system may function as a beneficial instrumentality for medical practitioners,facilitating the decision-making process concerning suture techniques in the context of duodenal SMTs.
