The climate system models from Beijing Climate Center, BCC_CSM1.1 and BCC_CSM1.1-M, are used to carry out most of the CMIP5 experiments. This study gives a general introduction of these two models, and provides main i...The climate system models from Beijing Climate Center, BCC_CSM1.1 and BCC_CSM1.1-M, are used to carry out most of the CMIP5 experiments. This study gives a general introduction of these two models, and provides main information on the experiments including the experiment purpose, design, and the external forcings. The transient climate responses to the CO2 concentration increase at 1% per year are presented in the simulation of the two models. The BCC_CSM1.1-M result is closer to the CMIP5 multiple models ensemble. The two models perform well in simulating the historical evolution of the surface air temperature, globally and averaged for China. Both models overestimate the global warming and underestimate the warming over China in the 20th century. With higher horizontal resolution, the BCC_CSM1.1-M has a better capability in reproducing the annual evolution of surface air temperature over China.展开更多
Respiratory infections are associated with high morbidity and mortality and are a major global health problem[1].Acute respiratory infections are caused by multiple respiratory pathogens,including viruses and bacteria...Respiratory infections are associated with high morbidity and mortality and are a major global health problem[1].Acute respiratory infections are caused by multiple respiratory pathogens,including viruses and bacteria.Viral-bacterial co-infections,which have become increasingly common and a global concern,can lead to substantial complications,causing higher morbidity and adverse prognosis[2].Previous studies have reported low positive detection rates of targeted pathogens related to acute respiratory infections,owing to the limited number of detected pathogens and variations in the sensitivity of diagnostic methods[3-4].Low positive detection rates may impede our understanding of respiratory pathogen characteristics and hamper the development of precise treatment and prevention strategies.展开更多
Background:C hina is a high-burden country for multidrug-r esistant tuberculosis/rifampin-resistant tuberculosis(MDR/RR-T B).Fluoroquinolones(FQs)are key drugs for the treatment of patients with MDR/RR-T B.However,res...Background:C hina is a high-burden country for multidrug-r esistant tuberculosis/rifampin-resistant tuberculosis(MDR/RR-T B).Fluoroquinolones(FQs)are key drugs for the treatment of patients with MDR/RR-T B.However,research on the resistance of FQs in Beijing is limited.Methods:W e collected clinical isolates from all patients with pulmonary TB in Beijing from January 2016 to December 2021,conducted drug-s ensitivity tests and sequencing for levofloxacin(LFX)and moxifloxacin(MFX),and collected the treatment plans and outcomes of the patients.Results:A total of 8512 clinical isolates were collected from patients with pulmonary TB,and 261 RR-T B strains were screened.The proportions of drug-s ensitive and drugresistant strains significantly differed by age group and treatment history.The rates of LFX and MFX resistance were 27.6%(72/261)and 36.4%(95/261),respectively.The detection rates of MDR-T B and pre-e xtensively drug-resistant TB(pre-X DR-T B)were 73.2%(191/261)and 36.4%(95/261),respectively,and the trends were significant(χ^(2)trend=9.995,p=0.002;χ^(2)trend=12.744,p=0.026).Among the 261 RR-T B strains,14.9%(24/261)were sensitive to LFX but resistant to MFX.Among the four patients with LFX-r esistant TB who received LFX treatment failed in three patients(Fisher's exact test,p=0.009).The common mutation sites were 94 and 90 in gyrA.A novel mutation Ala90Ser was discovered.Conclusions:F Qs resistance trends in RR-T B patients in Beijing are striking.Strains showed incomplete cross-resistance to LFX and MFX.Testing for FQs resistance and developing a reasonable treatment plan are recommended.Attention should be given to the changing trends in MDR-T B and pre-X DR-TB.展开更多
Objective To explore the effects of particulate matters less than 2.5 μm in aerodynamic diameter （PM2.5） on heart repolarization/depolarization and heart rate variability （HRV）. Methods We conducted a panel study...Objective To explore the effects of particulate matters less than 2.5 μm in aerodynamic diameter （PM2.5） on heart repolarization/depolarization and heart rate variability （HRV）. Methods We conducted a panel study for elderly subjects with heart disease in Beijing from 2007 to 2008. PM2.5 was measured at a fixed station for 20 h continuously each day while electrocardiogram （ECG） indexes of 42 subjects were also recorded repeatedly. Meteorological data was obtained from the China Meteorological Data Sharing Service System. A mixed linear regression model was used to estimate the associations between PMz.s and the ECG indexes. The model was adjusted for age, body mass index, sex, day of the week and meteorology. Results Significant adverse effects of PM2.5 on ECG indexes reflecting HRV were observed statistically and the strongest effect of PM2.s on HRV was on lag i day in our study. However, there were no associations between PM2.5 and ECG indexes reflecting heart repolarization/depolarization. Additionally, the effects of PM2.5 on subjects with hypertension were larger than on the subjects without hypertension. Conclusion This study showed ambient PM2.5could affect cardiac autonomic function of the elderly people with heart disease, and subjects with hypertension appeared to be more susceptive to the autonomic dysfunction induced by PM2.5.展开更多
Alternaria mycotoxins are of concern due to its adverse health effect, they affect various cereal crops and grain-based food along with modified forms that contribute to overall exposure. This study aimed to determine...Alternaria mycotoxins are of concern due to its adverse health effect, they affect various cereal crops and grain-based food along with modified forms that contribute to overall exposure. This study aimed to determine the frequency and level of exposure to Alternaria mycotoxins(tenuazonic acid, TeA;alternariol, AOH;alternariol monomethyl ether, AME;tentoxin, TEN;and altenuene, ALT) in human urine from Beijing adults. A total of 2212 urine samples were collected and analyzed for five mycotoxins using LC–ESI–MS/MS. More than98% of the samples had at least one Alternaria mycotoxin detected. Among the mycotoxins,AME had the highest detection rate(96.0%), followed by TeA(70.5%). The calculated average daily intake values of AME(12.5 ng/kg b.w.) was 5 times the TTC value(2.5 ng/kg b.w.) set by the EFSA, indicating the potential health risks associated with mycotoxins. Immediate attention and subsequent actions should be taken to identify the sources of mycotoxins and the corresponding exposure pathways to humans in the investigated regions.展开更多
The Miyun area of Beijing is located in the northern part of the North China Craton （NCC） and includes a variety of Archean granitoids and metamorphic rocks. Magmatic domains in zircon from a tonalite reveal Early N...The Miyun area of Beijing is located in the northern part of the North China Craton （NCC） and includes a variety of Archean granitoids and metamorphic rocks. Magmatic domains in zircon from a tonalite reveal Early Neoarchean （2752±7 Ma） ages show a small range in εHf（t） from 3.1 to 7.4 and tDM1（Hf） from 2742 to 2823 Ma, similar to their U-Pb ages, indicating derivation from a depleted mantle source only a short time prior to crystallization. SHRIMP zircon ages of granite, gneiss, amphibolite and hornblendite in the Miyun area reveal restricted emplacement ages from 2594 to 2496 Ma. They also record metamorphic events at ca. 2.50 Ga, 2.44 Ga and 1.82 Ga, showing a similar evolutionary history to the widely distributed Late Neoarchean rocks in the NCC. Positive eHf（t） values of 1.5 to 5.9, with model ages younger than 3.0 Ga for magmatic zircon domains from these Late Neoarchean intrusive rocks indicate that they are predominantly derived from juvenile crustal sources and suggest that significant crustal growth occurred in the northern NCC during the Neoarchean. Late Paleoproterozoic metamorphism developed widely in the NCC, not only in the Trans-North China Orogen, but also in areas of Eastern and Western Blocks, which suggest that the late Paleoproterozoic was the assembly of different micro-continents, which resulted in the final consolidation to form the NCC, and related to the development of the Paleo-Mesoproterozoic Columbia or Nuna supercontinent.展开更多
Hand,foot,and mouth disease (HFMD) is an acute infection caused by enteroviruses that is commonly seen in children^([1]).High infectivity,large number of asymptomatic infections,complex transmission routes,and rapid s...Hand,foot,and mouth disease (HFMD) is an acute infection caused by enteroviruses that is commonly seen in children^([1]).High infectivity,large number of asymptomatic infections,complex transmission routes,and rapid spread make it difficult to control HFMD.Since 2008,China has reported> 23 million HFMD cases,including>0.15million severe cases^([2]).HFMD tops the list of notifiable infectious diseases in terms of case number and incidence rate,leading to a huge disease burden^([3]).Timely and accurate assessment of HFMD epidemics is essential for a holistic understanding of the outbreaks and for effective prevention and control strategies.Currently,there are no quantitative indicators to determine the duration and intensity of HFMD epidemics in Beijing.展开更多
A retrospective surveillance study on enterovirus D68 was performed in Beijing, China, following the largest and most widespread EV-D68 infection, which occurred in the USA. From January 2011 to July 2015, EV-D68 was ...A retrospective surveillance study on enterovirus D68 was performed in Beijing, China, following the largest and most widespread EV-D68 infection, which occurred in the USA. From January 2011 to July 2015, EV-D68 was identified in 12 individuals with respiratory infections in Beijing, China. The phylogenetic relationships based on the genomic sequence alignment showed that there were two lineages circulating in Beijing from 2011 to 2015. Eight EV-D68 strains belonged to group 1 and four belonged to group 3. All EV-D68 strains from Beijing in 2014 were separately clustered into subgroup II of group 1. Based on these results, we concluded that the Beijing EV-D68 strains had little association with the EV-D68 strains circulating in the 2014 USA outbreak.展开更多
Laboratory-based pathogen isolation, identification, and toxicity determination were performed on samples from a suspected case of infant botulism. Mice injected with cultures generated from the enema sample and inges...Laboratory-based pathogen isolation, identification, and toxicity determination were performed on samples from a suspected case of infant botulism. Mice injected with cultures generated from the enema sample and ingested Powered infant formula （PIF） presented typical signs of botulism. Antitoxins to polyvalent botulinum neurotoxins （BoNTs） and monovalent BoNT type B antitoxin had protective effects. Clostridium botulinum isolated from the enema and residual PIF samples were positive for type B toxin. Pulsed-field gel electrophoresis （PFGE） revealed that the two strains of C. botulinum isolated from the two samples produced indistinguishable pulsotypes. These findings confirmed this case of type B infant botulism associated with the ingestion of PIF contaminated bv type B C. botulinum spores.展开更多
The present study examined the diurnal variations of summer precipitation in the Beijing area by usingsubdaily precipitation and wind observations. A combined effect of topography and urbanization on thecharacteristic...The present study examined the diurnal variations of summer precipitation in the Beijing area by usingsubdaily precipitation and wind observations. A combined effect of topography and urbanization on thecharacteristics of diurnal variations was suggested. It was shown that stations located in the plain areaexhibited typical night rain peaks, whereas those in the mountainous area exhibited clear afternoon peaks ofprecipitation diurnal variations. The precipitation peaks were associated with wind fields around the Beijingarea, which were found to be highly modulated by mountain-valley circulation and urban-country circulation.The lower-tropospheric wind exhibited a clear diurnal shift in its direction from north at 0800 LST to southat 2000 LST, which reflected mountain-valley circulation. The transitions from valley to mountain windand the opposite generally happened after sunset and sunrise, respectively, and both occurred earlier for thestations located closer to mountains. By comparing the diurnal variations of precipitation at stations in anortheast suburb, an urban area, and a southwest suburb, it was revealed that the northeast suburb grouphad the highest normalized rainfall frequency, but the southwest group had the lowest from late afternoon tolate evening. On the contrary, in the early morning from about 0200 to 1000 LST, the southwest group andurban group had the highest normalized rainfall frequency. This pattern might originate from the combinedeffects of mountain-valley topography and urbanization.展开更多
Streptococcus pneumoniae is a primary cause of illness and death among children younger than 5 years in China. The heptavalent pneumococcal conjugate vaccine (PCV7) was the only conjugated vaccine (PCV) available in C...Streptococcus pneumoniae is a primary cause of illness and death among children younger than 5 years in China. The heptavalent pneumococcal conjugate vaccine (PCV7) was the only conjugated vaccine (PCV) available in China from 2008 to 2013. This randomized, controlled, open-label study conducted at 46 Beijing clinics involved 3281 healthy 2-5-year-old Chinese children, randomized 1:1 to receive one dose of the S. pneumoniae heptavalent conjugated vaccine (PCV7) (n = 1643) or Haemophilus influenzae type b conjugate vaccine (Hib) (n = 1638). The main objective of this study was to investigate the impact of PCV7 against that of Hib vaccination in the nasopharyngeal S. pneumoniae colonization in healthy Chinese children. Nasopharyngeal (NP) samples for culture, serotyping and antimicrobial susceptibility testing were collected before vaccination and at Day 60 and 180 post-vaccination. A total 3281 children were enrolled in the study. Demographic characteristics were similar among both study groups: 1641 children received PCV7. Before immunization, S. pneumoniae was isolated in 338 and 360 children in the PCV7 (144 PCV7 isolates) and Hib groups (145 PCV7 isolates), respectively. At Day 180, PCV7 vaccination was more effective than Hib vaccination in reduction NP carriage (20.2% [P = 0.052]) and new acquisition (19.0% [P = 0.066]). When reductions in NP carriage and new acquisition of PCV7 VT plus 6A was analyzed, reduction in the PCV7 vaccinated group achieved statistical significance (P = 0.034 and P = 0.042 versus Hib, respectively). NP carriage of NVT increased in both groups (P = 0.305 between study groups at Day 180). PCV7 decreased NP carriage of non-susceptible VT to amoxicillin (P = 0.000), ceftriaxone (P = 0.047) and MDR (P = 0.024) versus Hib. PCV7 vaccination in Chinese children 2 to 5 years of age was more effective than vaccination with Hib in the reduction of S. pneumoniae nasopharyngeal carriage, new acquisition and non-susceptible isolates.展开更多
Since the outbreak of COVID-19,countries and regions worldwide have implemented multifaceted prevention and control measures,including vaccinations,antiviral drugs,mask wearing,and social distancing.However,omicron va...Since the outbreak of COVID-19,countries and regions worldwide have implemented multifaceted prevention and control measures,including vaccinations,antiviral drugs,mask wearing,and social distancing.However,omicron variants,with significantly increased endogenous and occult transmission.展开更多
Coxsackievirus A24 variant(CVA24v)is a major pathogen that causes continued outbreaks and pandemics of acute hemorrhagic conjunctivitis(AHC).In China,the first confirmed outbreak of CVA24v-related AHC occurred in Beij...Coxsackievirus A24 variant(CVA24v)is a major pathogen that causes continued outbreaks and pandemics of acute hemorrhagic conjunctivitis(AHC).In China,the first confirmed outbreak of CVA24v-related AHC occurred in Beijing in 1988,followed by another two significant outbreaks respectively in 1994 and 2007,which coincides with the three-stage dynamic distribution of AHC in the world after 1970s.To illustrate the genetic characteristics of CVA24v in different periods,a total of 23 strains were isolated from those three outbreaks and the whole genome of those isolations were sequenced and analyzed.Compared with the prototype strain,the 23 strains shared four nucleotide deletions in the 5'UTR except the 0744 strain isolated in 2007.And at the 98th site,one nucleotide insertion was found in all the strains collected from 2007.From 1994 to 2007,amino acid polarity in the VP1 region at the 25th and the 32nd site were changed.Both the 3C and VP1 phylogenetic tree indicated that isolates from 1988 and 1994 belonged to Genotype III(GIII),and 2007 strains to Genotype IV(GIV).According to the Bayesian analysis based on complete genome sequence,the most recent common ancestors for the isolates in1988,1994 and 2007 were respectively estimated around October 1987,February 1993 and December 2004.The evolutionary rate of the CVA24v was estimated to be 7.45×10^(-3) substitutions/site/year.Our study indicated that the early epidemic of CVA24v in Chinese mainland was the GIII.Point mutations and amino acid changes in different genotypes of CVA24v may generate intensity differences of the AHC outbreak.CVA24v has been evolving constantly with a relatively rapid rate.展开更多
SHRIMP U-Pb dating of diagenetic xenotime from sedimentary rocks has provided age constraints for sedimentary diagenesis （McNaughton et al., 1999; Fletcher et al., 2000; England et al., 2001; Rasmussen et al., 2004; ...SHRIMP U-Pb dating of diagenetic xenotime from sedimentary rocks has provided age constraints for sedimentary diagenesis （McNaughton et al., 1999; Fletcher et al., 2000; England et al., 2001; Rasmussen et al., 2004; Vallini et al., 2007）. Xenotime （YPO4） may grow during early diagenesis, typically being present as a trace constituent in siliciclastic sedimentary rocks （Rasmussen, 2005）, in the form of syntaxial outgrowths on detrital zircon grains. Diagenetic xenotime occurs in a wide variety of rock types, including conglomerate,展开更多
It is very important to provide reference basis for winter wheat quality regionalization of cultivation area. The aim of this article was based on factors affecting wheat quality and setting realistic spatial models i...It is very important to provide reference basis for winter wheat quality regionalization of cultivation area. The aim of this article was based on factors affecting wheat quality and setting realistic spatial models in each part of the land for assessment of land suitability potentials in Beijing, China. The study employed artificial neural network （ANN） analysis to select factors and evaluate the relative importance of selected environment factors on wheat grain quality. The spatial models were developed and demonstrated their use in selecting the most suitable areas for the winter wheat cultivation. The strategy overcomes the non-accurate traditional statistical methods. Satellite images, toposheet, and ancillary data of the study area were used to find tillable land. These categories were formed by integrating the various layers with corresponding weights in geographical information system （GIS）. An integrated land suitability potential （LSP） index was computed considering the contribution of various parameters of land suitability. The study demonstrated that the tillable land could be categorized into spatially distributed agriculture potential zones based on soil nutrient and assembled weather factors using RS and GIS as not suitable, marginally suitable, moderately suitable, suitable, and highly suitable by adopting the logical criteria. The sort of land distribution map made by the factors with their weights showed more truthfulness.展开更多
The Yunmengshan Geopark in northern Beijing is located within the Yanshan range. It contains the Yunmengshan batholith, which is dominated by two plutons： the Yunmengshan gneissic granite and the Shicheng gneissic di...The Yunmengshan Geopark in northern Beijing is located within the Yanshan range. It contains the Yunmengshan batholith, which is dominated by two plutons： the Yunmengshan gneissic granite and the Shicheng gneissic diorite. Four samples of the Yunmengshan gneissic granite give SHRIMP zircon U-Pb ages from 145 to 141 Ma, whereas four samples of the Shicheng gneissic diorite have ages from 159 Ma to 151 Ma. Dikes that cut the Yunmengshan diorite record SHRIMP zircon U-Pb age of 162±2 and 156±4 Ma. The cumulative plots of zircons from the diorites show a peak age of 155 Ma, without inherited zircon cores, and the peak age of 142 Ma for granite is interpreted as the emplacement age of the Yunmengshan granitic pluton, whose igneous zircons contain inherited zircon cores. The data presented here show that there were two pulses of magmatism： early diorites, followed c13 Ma later by true granites, which incorporated material from an older continental crust.展开更多
Objective There are evidences that heat wave events cause deaths and emergency cases. This article used the contingent valuation method to find the willingness to pay for the protective measures and investigated the f...Objective There are evidences that heat wave events cause deaths and emergency cases. This article used the contingent valuation method to find the willingness to pay for the protective measures and investigated the factors that influence the willingness to pay. Methods A cross-sectional face-to-face household survey was completed by 637 urban long-term residents and 591 rural long-term residents aged 15-79 in Beijing, China. Binary logistic regression was used to identify factors that influenced the payment rate or payment amount for the protective measures, including independent variables for district, gender, age, education, income, air conditioner ownership, heat wave experience, and chronic non-communicable disease. Results The payment rate was 41.1% for protective measures provided by the government and 39.5% by measures provided by the market. Most of the respondents were willing to pay 40 CNY per capita annually for measures provided by the government or the market. The factors influencing willingness to pay were district, gender, income, air conditioner ownership, heat wave experience, and chronic non-communicable disease. Conclusion Protective measures for heat waves need to be provided immediately. More attention should be paid to the situation of vulnerable groups, such as people who live in urban areas, those without air conditioning, and those who have experienced a heat wave in the past.展开更多
Detrital zircons in five sedimentary samples, MC1 to MC5, from the bottom of the Chuanlinggou Formation in the Ming Tombs District, Beijing, were dated with the LA-ICP-MS and SHRIMP U-Pb methods. Age spectra of the fi...Detrital zircons in five sedimentary samples, MC1 to MC5, from the bottom of the Chuanlinggou Formation in the Ming Tombs District, Beijing, were dated with the LA-ICP-MS and SHRIMP U-Pb methods. Age spectra of the five samples show a major peak at 2500 Ma and a secondary peak at 2000 Ma, suggesting their provenances were mainly from the crystalline basement of the North China Craton and the Trans-North China Orogen. The youngest zircon has an age of 1673 d： 44 Ma, indicating that the Chuanlinggou Formation was deposited after this age. From sample MC4 to MC5, lithology changed from a clastic rock （fine-grained sandstone） to a carbonate rock （fine-grained dolomite）, suggesting that the depositional basin became progressively deeper. The age spectrum of sample MC5 shows a major peak at 2500 Ma and a secondary peak at 2000 Ma. Sample MC4, which is stratigraphically lower than sample MC5, only had one peak at 2500 Ma. We conclude that there was a transgressive event when sediments represented by MC5 was deposited, and seawater carried ca. 2000 Ma clastic materials to the basin where the Chuanlinggou Formation was deposited, leading to the addition of ca. 2000 Ma detritus. Our research indicates that the source area for the sediments became more extensive with time. We conclude that the Chuanlinggou Formation in the Ming Tombs District was deposited in a low-energy mud fiat sedimentary environment in the inter-supra tidal zone because it is mainly composed of silty mudstone and fine-grained sandstone with relatively simple sedimentary structures.展开更多
According to intensity distribution of the synchrotron radiation source focused by a toroidal mirror at the Beijing synchrotron radiation biological macromolecule station, theoretical modeling of the Beijing synchrotr...According to intensity distribution of the synchrotron radiation source focused by a toroidal mirror at the Beijing synchrotron radiation biological macromolecule station, theoretical modeling of the Beijing synchrotron radiation source is developed for capillary optics. Using this theoretical modeling, the influences of the configuration curve of the polycapillary X-ray lens on transmission efficiency and working distance are analyzed. The experimental results of the transmission efficiency and working distance at the biological macromolecule station are in good agreement with the theoretical results.展开更多
Gaseous peroxides play important roles in atmospheric chemistry. To understand the pathways of the formation and removal of peroxides, atmospheric peroxide concentrations and their controlling factors were measured fr...Gaseous peroxides play important roles in atmospheric chemistry. To understand the pathways of the formation and removal of peroxides, atmospheric peroxide concentrations and their controlling factors were measured from 7：00 to 20：00 in September, October, and November 2013 at a heavily trafficked residential site in Beijing, China, with average concentrations of hydrogen peroxide（H2O2） and methyl hydroperoxide（MHP） at 0.55 ppb and 0.063 ppb, respectively. H2O2 concentrations were higher in the afternoon and lower in the morning and evening, while MHP concentrations did not exhibit a regular diurnal pattern. Both H2O2 and MHP concentrations increased at dusk in most cases. Both peroxides displayed monthly variations with higher concentrations in September. These results suggested that photochemical activity was the main controlling factor on variations of H2O2 concentrations during the measurement period. Increasing concentrations of volatile organic compounds emitted by motor vehicles were important contributors to H2O2 and MHP enrichment. High levels of H2O2 and MHP concentrations which occurred during the measurement period probably resulted from the transport of a polluted air mass with high water vapor content passing over the Bohai Bay, China.展开更多
基金supported by the National Basic Research Program of China (973 Program) under No. 2010CB951903the National Science Foundation of China under Grant No. 41105054, 41205043the China Meteorological Administration under Grant No.GYHY201106022, GYHY201306048, CMAYBY2012-001
文摘The climate system models from Beijing Climate Center, BCC_CSM1.1 and BCC_CSM1.1-M, are used to carry out most of the CMIP5 experiments. This study gives a general introduction of these two models, and provides main information on the experiments including the experiment purpose, design, and the external forcings. The transient climate responses to the CO2 concentration increase at 1% per year are presented in the simulation of the two models. The BCC_CSM1.1-M result is closer to the CMIP5 multiple models ensemble. The two models perform well in simulating the historical evolution of the surface air temperature, globally and averaged for China. Both models overestimate the global warming and underestimate the warming over China in the 20th century. With higher horizontal resolution, the BCC_CSM1.1-M has a better capability in reproducing the annual evolution of surface air temperature over China.
基金supported by the Beijing Science and Technology Planning Project of the Beijing Science and Technology Commission(Z241100009024047)the High-Level Public Health Technical Talent Training Plan(lingjunrencai-01-02).
文摘Respiratory infections are associated with high morbidity and mortality and are a major global health problem[1].Acute respiratory infections are caused by multiple respiratory pathogens,including viruses and bacteria.Viral-bacterial co-infections,which have become increasingly common and a global concern,can lead to substantial complications,causing higher morbidity and adverse prognosis[2].Previous studies have reported low positive detection rates of targeted pathogens related to acute respiratory infections,owing to the limited number of detected pathogens and variations in the sensitivity of diagnostic methods[3-4].Low positive detection rates may impede our understanding of respiratory pathogen characteristics and hamper the development of precise treatment and prevention strategies.
基金The Research and Cultivation Spectial Project of Beijing Center for Disease Prevention and Control,Grant/Award Number:2023-KYJH-03。
文摘Background:C hina is a high-burden country for multidrug-r esistant tuberculosis/rifampin-resistant tuberculosis(MDR/RR-T B).Fluoroquinolones(FQs)are key drugs for the treatment of patients with MDR/RR-T B.However,research on the resistance of FQs in Beijing is limited.Methods:W e collected clinical isolates from all patients with pulmonary TB in Beijing from January 2016 to December 2021,conducted drug-s ensitivity tests and sequencing for levofloxacin(LFX)and moxifloxacin(MFX),and collected the treatment plans and outcomes of the patients.Results:A total of 8512 clinical isolates were collected from patients with pulmonary TB,and 261 RR-T B strains were screened.The proportions of drug-s ensitive and drugresistant strains significantly differed by age group and treatment history.The rates of LFX and MFX resistance were 27.6%(72/261)and 36.4%(95/261),respectively.The detection rates of MDR-T B and pre-e xtensively drug-resistant TB(pre-X DR-T B)were 73.2%(191/261)and 36.4%(95/261),respectively,and the trends were significant(χ^(2)trend=9.995,p=0.002;χ^(2)trend=12.744,p=0.026).Among the 261 RR-T B strains,14.9%(24/261)were sensitive to LFX but resistant to MFX.Among the four patients with LFX-r esistant TB who received LFX treatment failed in three patients(Fisher's exact test,p=0.009).The common mutation sites were 94 and 90 in gyrA.A novel mutation Ala90Ser was discovered.Conclusions:F Qs resistance trends in RR-T B patients in Beijing are striking.Strains showed incomplete cross-resistance to LFX and MFX.Testing for FQs resistance and developing a reasonable treatment plan are recommended.Attention should be given to the changing trends in MDR-T B and pre-X DR-TB.
基金supported by the National Natural Science Foundation of China (Grant No. 20637020)
文摘Objective To explore the effects of particulate matters less than 2.5 μm in aerodynamic diameter （PM2.5） on heart repolarization/depolarization and heart rate variability （HRV）. Methods We conducted a panel study for elderly subjects with heart disease in Beijing from 2007 to 2008. PM2.5 was measured at a fixed station for 20 h continuously each day while electrocardiogram （ECG） indexes of 42 subjects were also recorded repeatedly. Meteorological data was obtained from the China Meteorological Data Sharing Service System. A mixed linear regression model was used to estimate the associations between PMz.s and the ECG indexes. The model was adjusted for age, body mass index, sex, day of the week and meteorology. Results Significant adverse effects of PM2.5 on ECG indexes reflecting HRV were observed statistically and the strongest effect of PM2.s on HRV was on lag i day in our study. However, there were no associations between PM2.5 and ECG indexes reflecting heart repolarization/depolarization. Additionally, the effects of PM2.5 on subjects with hypertension were larger than on the subjects without hypertension. Conclusion This study showed ambient PM2.5could affect cardiac autonomic function of the elderly people with heart disease, and subjects with hypertension appeared to be more susceptive to the autonomic dysfunction induced by PM2.5.
基金supported by the National Key Research and Development Program of China (Nos. 2017YFC1600500, 2019YFF0216303)the Research Special Found for Municipal Medical Public Welfare institute (No. 2017-BJYJ-15)the Research Project of the National Institute of Metrology (Nos. AKY1934, 31-AKYZZ2039)。
文摘Alternaria mycotoxins are of concern due to its adverse health effect, they affect various cereal crops and grain-based food along with modified forms that contribute to overall exposure. This study aimed to determine the frequency and level of exposure to Alternaria mycotoxins(tenuazonic acid, TeA;alternariol, AOH;alternariol monomethyl ether, AME;tentoxin, TEN;and altenuene, ALT) in human urine from Beijing adults. A total of 2212 urine samples were collected and analyzed for five mycotoxins using LC–ESI–MS/MS. More than98% of the samples had at least one Alternaria mycotoxin detected. Among the mycotoxins,AME had the highest detection rate(96.0%), followed by TeA(70.5%). The calculated average daily intake values of AME(12.5 ng/kg b.w.) was 5 times the TTC value(2.5 ng/kg b.w.) set by the EFSA, indicating the potential health risks associated with mycotoxins. Immediate attention and subsequent actions should be taken to identify the sources of mycotoxins and the corresponding exposure pathways to humans in the investigated regions.
基金financially supported by the National Natural Science Foundation of China(grants No.41173065 and 40703012)the China Geological Survey(grants No.1212011121075, 12120114020901,12120113094000 and 1212011120332)the Basic Outlay of Scientific Research Work from the Ministry of Science and Technology of the People's Republic of China(grant No.J1403)
文摘The Miyun area of Beijing is located in the northern part of the North China Craton （NCC） and includes a variety of Archean granitoids and metamorphic rocks. Magmatic domains in zircon from a tonalite reveal Early Neoarchean （2752±7 Ma） ages show a small range in εHf（t） from 3.1 to 7.4 and tDM1（Hf） from 2742 to 2823 Ma, similar to their U-Pb ages, indicating derivation from a depleted mantle source only a short time prior to crystallization. SHRIMP zircon ages of granite, gneiss, amphibolite and hornblendite in the Miyun area reveal restricted emplacement ages from 2594 to 2496 Ma. They also record metamorphic events at ca. 2.50 Ga, 2.44 Ga and 1.82 Ga, showing a similar evolutionary history to the widely distributed Late Neoarchean rocks in the NCC. Positive eHf（t） values of 1.5 to 5.9, with model ages younger than 3.0 Ga for magmatic zircon domains from these Late Neoarchean intrusive rocks indicate that they are predominantly derived from juvenile crustal sources and suggest that significant crustal growth occurred in the northern NCC during the Neoarchean. Late Paleoproterozoic metamorphism developed widely in the NCC, not only in the Trans-North China Orogen, but also in areas of Eastern and Western Blocks, which suggest that the late Paleoproterozoic was the assembly of different micro-continents, which resulted in the final consolidation to form the NCC, and related to the development of the Paleo-Mesoproterozoic Columbia or Nuna supercontinent.
基金supported by National Key R&D Program of China [2021ZD0114103]Capital’s Funds for Health Improvement and Research [2022-1G-3014]+3 种基金High Level Public Health Technical Talent Training Plan [xuekegugan-01-019]High Level Public Health Technical Talent Training Plan [xuekedaitouren-01-03]Beijing Natural Science Foundation[7202073]Key research projects of Beijing Natural Science Foundation-Haidian District Joint Fund [L192012]。
文摘Hand,foot,and mouth disease (HFMD) is an acute infection caused by enteroviruses that is commonly seen in children^([1]).High infectivity,large number of asymptomatic infections,complex transmission routes,and rapid spread make it difficult to control HFMD.Since 2008,China has reported> 23 million HFMD cases,including>0.15million severe cases^([2]).HFMD tops the list of notifiable infectious diseases in terms of case number and incidence rate,leading to a huge disease burden^([3]).Timely and accurate assessment of HFMD epidemics is essential for a holistic understanding of the outbreaks and for effective prevention and control strategies.Currently,there are no quantitative indicators to determine the duration and intensity of HFMD epidemics in Beijing.
基金supported by the Beijing Municipal Science and Technology Commission(Z151100003915140)Capital Medical Development and scientific research fund(2016-2-3011)National Major Science and Technology Project for Control and Prevention of Major Infectious Diseases of China(2016ZX10004206)
文摘A retrospective surveillance study on enterovirus D68 was performed in Beijing, China, following the largest and most widespread EV-D68 infection, which occurred in the USA. From January 2011 to July 2015, EV-D68 was identified in 12 individuals with respiratory infections in Beijing, China. The phylogenetic relationships based on the genomic sequence alignment showed that there were two lineages circulating in Beijing from 2011 to 2015. Eight EV-D68 strains belonged to group 1 and four belonged to group 3. All EV-D68 strains from Beijing in 2014 were separately clustered into subgroup II of group 1. Based on these results, we concluded that the Beijing EV-D68 strains had little association with the EV-D68 strains circulating in the 2014 USA outbreak.
基金financially supported by the National Natural Science Foundation of China for Youth Fund Project:Integrated Identification and Risk Assessment of Clostridium and its Metabolites(81402684)
文摘Laboratory-based pathogen isolation, identification, and toxicity determination were performed on samples from a suspected case of infant botulism. Mice injected with cultures generated from the enema sample and ingested Powered infant formula （PIF） presented typical signs of botulism. Antitoxins to polyvalent botulinum neurotoxins （BoNTs） and monovalent BoNT type B antitoxin had protective effects. Clostridium botulinum isolated from the enema and residual PIF samples were positive for type B toxin. Pulsed-field gel electrophoresis （PFGE） revealed that the two strains of C. botulinum isolated from the two samples produced indistinguishable pulsotypes. These findings confirmed this case of type B infant botulism associated with the ingestion of PIF contaminated bv type B C. botulinum spores.
基金supported by grants from the National Basic Key Research Program (973) under Grant No. 2006CB403606the National Key Technology R&D Program under Grant No. 2007BAC29B04the National Science Foundation Project for Post-doctoral Scientists of China under Grant No. 20080440343
文摘The present study examined the diurnal variations of summer precipitation in the Beijing area by usingsubdaily precipitation and wind observations. A combined effect of topography and urbanization on thecharacteristics of diurnal variations was suggested. It was shown that stations located in the plain areaexhibited typical night rain peaks, whereas those in the mountainous area exhibited clear afternoon peaks ofprecipitation diurnal variations. The precipitation peaks were associated with wind fields around the Beijingarea, which were found to be highly modulated by mountain-valley circulation and urban-country circulation.The lower-tropospheric wind exhibited a clear diurnal shift in its direction from north at 0800 LST to southat 2000 LST, which reflected mountain-valley circulation. The transitions from valley to mountain windand the opposite generally happened after sunset and sunrise, respectively, and both occurred earlier for thestations located closer to mountains. By comparing the diurnal variations of precipitation at stations in anortheast suburb, an urban area, and a southwest suburb, it was revealed that the northeast suburb grouphad the highest normalized rainfall frequency, but the southwest group had the lowest from late afternoon tolate evening. On the contrary, in the early morning from about 0200 to 1000 LST, the southwest group andurban group had the highest normalized rainfall frequency. This pattern might originate from the combinedeffects of mountain-valley topography and urbanization.
文摘Streptococcus pneumoniae is a primary cause of illness and death among children younger than 5 years in China. The heptavalent pneumococcal conjugate vaccine (PCV7) was the only conjugated vaccine (PCV) available in China from 2008 to 2013. This randomized, controlled, open-label study conducted at 46 Beijing clinics involved 3281 healthy 2-5-year-old Chinese children, randomized 1:1 to receive one dose of the S. pneumoniae heptavalent conjugated vaccine (PCV7) (n = 1643) or Haemophilus influenzae type b conjugate vaccine (Hib) (n = 1638). The main objective of this study was to investigate the impact of PCV7 against that of Hib vaccination in the nasopharyngeal S. pneumoniae colonization in healthy Chinese children. Nasopharyngeal (NP) samples for culture, serotyping and antimicrobial susceptibility testing were collected before vaccination and at Day 60 and 180 post-vaccination. A total 3281 children were enrolled in the study. Demographic characteristics were similar among both study groups: 1641 children received PCV7. Before immunization, S. pneumoniae was isolated in 338 and 360 children in the PCV7 (144 PCV7 isolates) and Hib groups (145 PCV7 isolates), respectively. At Day 180, PCV7 vaccination was more effective than Hib vaccination in reduction NP carriage (20.2% [P = 0.052]) and new acquisition (19.0% [P = 0.066]). When reductions in NP carriage and new acquisition of PCV7 VT plus 6A was analyzed, reduction in the PCV7 vaccinated group achieved statistical significance (P = 0.034 and P = 0.042 versus Hib, respectively). NP carriage of NVT increased in both groups (P = 0.305 between study groups at Day 180). PCV7 decreased NP carriage of non-susceptible VT to amoxicillin (P = 0.000), ceftriaxone (P = 0.047) and MDR (P = 0.024) versus Hib. PCV7 vaccination in Chinese children 2 to 5 years of age was more effective than vaccination with Hib in the reduction of S. pneumoniae nasopharyngeal carriage, new acquisition and non-susceptible isolates.
基金supported by the Ministry of Science and Technology of the People’s Republic of China。
文摘Since the outbreak of COVID-19,countries and regions worldwide have implemented multifaceted prevention and control measures,including vaccinations,antiviral drugs,mask wearing,and social distancing.However,omicron variants,with significantly increased endogenous and occult transmission.
基金funded by the National Science and Technology Major project of China(Project No.2017ZX10104001)the National key research and development project(Project No.2021YFC0863000)the Beijing Natural Science Foundation(Project No.L192014)。
文摘Coxsackievirus A24 variant(CVA24v)is a major pathogen that causes continued outbreaks and pandemics of acute hemorrhagic conjunctivitis(AHC).In China,the first confirmed outbreak of CVA24v-related AHC occurred in Beijing in 1988,followed by another two significant outbreaks respectively in 1994 and 2007,which coincides with the three-stage dynamic distribution of AHC in the world after 1970s.To illustrate the genetic characteristics of CVA24v in different periods,a total of 23 strains were isolated from those three outbreaks and the whole genome of those isolations were sequenced and analyzed.Compared with the prototype strain,the 23 strains shared four nucleotide deletions in the 5'UTR except the 0744 strain isolated in 2007.And at the 98th site,one nucleotide insertion was found in all the strains collected from 2007.From 1994 to 2007,amino acid polarity in the VP1 region at the 25th and the 32nd site were changed.Both the 3C and VP1 phylogenetic tree indicated that isolates from 1988 and 1994 belonged to Genotype III(GIII),and 2007 strains to Genotype IV(GIV).According to the Bayesian analysis based on complete genome sequence,the most recent common ancestors for the isolates in1988,1994 and 2007 were respectively estimated around October 1987,February 1993 and December 2004.The evolutionary rate of the CVA24v was estimated to be 7.45×10^(-3) substitutions/site/year.Our study indicated that the early epidemic of CVA24v in Chinese mainland was the GIII.Point mutations and amino acid changes in different genotypes of CVA24v may generate intensity differences of the AHC outbreak.CVA24v has been evolving constantly with a relatively rapid rate.
基金financially supported by the National Natural Science Foundation of China(grant No.41173065)Ministry of Land and Natural Resources(grant No.201311116)the Basic Outlay of Scientific Research Work from the Ministry of Science and Technology(No.J1403)
文摘SHRIMP U-Pb dating of diagenetic xenotime from sedimentary rocks has provided age constraints for sedimentary diagenesis （McNaughton et al., 1999; Fletcher et al., 2000; England et al., 2001; Rasmussen et al., 2004; Vallini et al., 2007）. Xenotime （YPO4） may grow during early diagenesis, typically being present as a trace constituent in siliciclastic sedimentary rocks （Rasmussen, 2005）, in the form of syntaxial outgrowths on detrital zircon grains. Diagenetic xenotime occurs in a wide variety of rock types, including conglomerate,
基金supported by the National Natural Science Foundation of China (40701120)the Beijing Nova Program, China (2008B33)the Beijing Natural Science Foundation, China (4092016)
文摘It is very important to provide reference basis for winter wheat quality regionalization of cultivation area. The aim of this article was based on factors affecting wheat quality and setting realistic spatial models in each part of the land for assessment of land suitability potentials in Beijing, China. The study employed artificial neural network （ANN） analysis to select factors and evaluate the relative importance of selected environment factors on wheat grain quality. The spatial models were developed and demonstrated their use in selecting the most suitable areas for the winter wheat cultivation. The strategy overcomes the non-accurate traditional statistical methods. Satellite images, toposheet, and ancillary data of the study area were used to find tillable land. These categories were formed by integrating the various layers with corresponding weights in geographical information system （GIS）. An integrated land suitability potential （LSP） index was computed considering the contribution of various parameters of land suitability. The study demonstrated that the tillable land could be categorized into spatially distributed agriculture potential zones based on soil nutrient and assembled weather factors using RS and GIS as not suitable, marginally suitable, moderately suitable, suitable, and highly suitable by adopting the logical criteria. The sort of land distribution map made by the factors with their weights showed more truthfulness.
基金supported by the National Natural Science Foundation of China(no.:40703012)the Basic Outlay of Scientific Research Work from the Ministry of Science and Technology of the Peoples Republic of China(no.:J0809),and Miyun Tourism Administration for the Yunmengshan National Geopark.
文摘The Yunmengshan Geopark in northern Beijing is located within the Yanshan range. It contains the Yunmengshan batholith, which is dominated by two plutons： the Yunmengshan gneissic granite and the Shicheng gneissic diorite. Four samples of the Yunmengshan gneissic granite give SHRIMP zircon U-Pb ages from 145 to 141 Ma, whereas four samples of the Shicheng gneissic diorite have ages from 159 Ma to 151 Ma. Dikes that cut the Yunmengshan diorite record SHRIMP zircon U-Pb age of 162±2 and 156±4 Ma. The cumulative plots of zircons from the diorites show a peak age of 155 Ma, without inherited zircon cores, and the peak age of 142 Ma for granite is interpreted as the emplacement age of the Yunmengshan granitic pluton, whose igneous zircons contain inherited zircon cores. The data presented here show that there were two pulses of magmatism： early diorites, followed c13 Ma later by true granites, which incorporated material from an older continental crust.
基金supported by National Natural Science Foundation of China(Project Number:21277135,91543111)Natural Science Foundation of Beijing Municipality(Project Number:8132048)
文摘Objective There are evidences that heat wave events cause deaths and emergency cases. This article used the contingent valuation method to find the willingness to pay for the protective measures and investigated the factors that influence the willingness to pay. Methods A cross-sectional face-to-face household survey was completed by 637 urban long-term residents and 591 rural long-term residents aged 15-79 in Beijing, China. Binary logistic regression was used to identify factors that influenced the payment rate or payment amount for the protective measures, including independent variables for district, gender, age, education, income, air conditioner ownership, heat wave experience, and chronic non-communicable disease. Results The payment rate was 41.1% for protective measures provided by the government and 39.5% by measures provided by the market. Most of the respondents were willing to pay 40 CNY per capita annually for measures provided by the government or the market. The factors influencing willingness to pay were district, gender, income, air conditioner ownership, heat wave experience, and chronic non-communicable disease. Conclusion Protective measures for heat waves need to be provided immediately. More attention should be paid to the situation of vulnerable groups, such as people who live in urban areas, those without air conditioning, and those who have experienced a heat wave in the past.
基金financially supported by the Ministry of Land and Natural Resources (Grant No. 201311116)the National Natural Science Foundation of China (Grant No. 41173065)+1 种基金Ministry of Science and Technology (No. 2012FY120100)the Basic Outlay of Scientific Research Work from the Ministry of Science and Technology (Grant No. J1403)
文摘Detrital zircons in five sedimentary samples, MC1 to MC5, from the bottom of the Chuanlinggou Formation in the Ming Tombs District, Beijing, were dated with the LA-ICP-MS and SHRIMP U-Pb methods. Age spectra of the five samples show a major peak at 2500 Ma and a secondary peak at 2000 Ma, suggesting their provenances were mainly from the crystalline basement of the North China Craton and the Trans-North China Orogen. The youngest zircon has an age of 1673 d： 44 Ma, indicating that the Chuanlinggou Formation was deposited after this age. From sample MC4 to MC5, lithology changed from a clastic rock （fine-grained sandstone） to a carbonate rock （fine-grained dolomite）, suggesting that the depositional basin became progressively deeper. The age spectrum of sample MC5 shows a major peak at 2500 Ma and a secondary peak at 2000 Ma. Sample MC4, which is stratigraphically lower than sample MC5, only had one peak at 2500 Ma. We conclude that there was a transgressive event when sediments represented by MC5 was deposited, and seawater carried ca. 2000 Ma clastic materials to the basin where the Chuanlinggou Formation was deposited, leading to the addition of ca. 2000 Ma detritus. Our research indicates that the source area for the sediments became more extensive with time. We conclude that the Chuanlinggou Formation in the Ming Tombs District was deposited in a low-energy mud fiat sedimentary environment in the inter-supra tidal zone because it is mainly composed of silty mudstone and fine-grained sandstone with relatively simple sedimentary structures.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 11179010 and 11075017 )the Natural Science Foundation of Beijing,China (Grant No. 1102019)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20100003120010)
文摘According to intensity distribution of the synchrotron radiation source focused by a toroidal mirror at the Beijing synchrotron radiation biological macromolecule station, theoretical modeling of the Beijing synchrotron radiation source is developed for capillary optics. Using this theoretical modeling, the influences of the configuration curve of the polycapillary X-ray lens on transmission efficiency and working distance are analyzed. The experimental results of the transmission efficiency and working distance at the biological macromolecule station are in good agreement with the theoretical results.
基金supported by the International Cooperation Project of MOST(No.2012DFG90290)the National Natural Science Foundation of China(No.4225001046)+1 种基金National Department Public Benefit Research Foundation(No.201509014)the Basic Foundation for Public Benefit-Research Academies from Centre Government(No.2010KYYW02)
文摘Gaseous peroxides play important roles in atmospheric chemistry. To understand the pathways of the formation and removal of peroxides, atmospheric peroxide concentrations and their controlling factors were measured from 7：00 to 20：00 in September, October, and November 2013 at a heavily trafficked residential site in Beijing, China, with average concentrations of hydrogen peroxide（H2O2） and methyl hydroperoxide（MHP） at 0.55 ppb and 0.063 ppb, respectively. H2O2 concentrations were higher in the afternoon and lower in the morning and evening, while MHP concentrations did not exhibit a regular diurnal pattern. Both H2O2 and MHP concentrations increased at dusk in most cases. Both peroxides displayed monthly variations with higher concentrations in September. These results suggested that photochemical activity was the main controlling factor on variations of H2O2 concentrations during the measurement period. Increasing concentrations of volatile organic compounds emitted by motor vehicles were important contributors to H2O2 and MHP enrichment. High levels of H2O2 and MHP concentrations which occurred during the measurement period probably resulted from the transport of a polluted air mass with high water vapor content passing over the Bohai Bay, China.
