Objective Observational studies have found associations between inflammatory bowel disease(IBD)and the risk of dementia,including Alzheimer’s dementia(AD)and vascular dementia(VD);however,these findings are inconsist...Objective Observational studies have found associations between inflammatory bowel disease(IBD)and the risk of dementia,including Alzheimer’s dementia(AD)and vascular dementia(VD);however,these findings are inconsistent.It remains unclear whether these associations are causal.Methods We conducted a meta-analysis by systematically searching for observational studies on the association between IBD and dementia.Mendelian randomization(MR)analysis based on summary genome-wide association studies(GWASs)was performed.Genetic correlation and Bayesian colocalization analyses were used to provide robust genetic evidence.Results Ten observational studies involving 80,565,688 participants were included in this metaanalysis.IBD was significantly associated with dementia(risk ratio[RR]=1.36,95%CI=1.04-1.78;I2=84.8%)and VD(RR=2.60,95%CI=1.18-5.70;only one study),but not with AD(RR=2.00,95%CI=0.96-4.13;I^(2)=99.8%).MR analyses did not supported significant causal associations of IBD with dementia(dementia:odds ratio[OR]=1.01,95%CI=0.98-1.03;AD:OR=0.98,95%CI=0.95-1.01;VD:OR=1.02,95%CI=0.97-1.07).In addition,genetic correlation and co-localization analyses did not reveal any genetic associations between IBD and dementia.Conclusion Our study did not provide genetic evidence for a causal association between IBD and dementia risk.The increased risk of dementia observed in observational studies may be attributed to unobserved confounding factors or detection bias.展开更多
Seasonal precipitation has always been a key focus of climate prediction.As a dynamic-statistical combined method,the existing observational constraint correction establishes a regression relationship between the nume...Seasonal precipitation has always been a key focus of climate prediction.As a dynamic-statistical combined method,the existing observational constraint correction establishes a regression relationship between the numerical model outputs and historical observations,which can partly predict seasonal precipitation.However,solving a nonlinear problem through linear regression is significantly biased.This study implements a nonlinear optimization of an existing observational constrained correction model using a Light Gradient Boosting Machine(LightGBM)machine learning algorithm based on output from the Beijing National Climate Center Climate System Model(BCC-CSM)and station observations to improve the prediction of summer precipitation in China.The model was trained using a rolling approach,and LightGBM outperformed Linear Regression(LR),Extreme Gradient Boosting(XGBoost),and Categorical Boosting(CatBoost).Using parameter tuning to optimize the machine learning model and predict future summer precipitation using eight different predictors in BCC-CSM,the mean Anomaly Correlation Coefficient(ACC)score in the 2019–22 summer precipitation predictions was 0.17,and the mean Prediction Score(PS)reached 74.The PS score was improved by 7.87%and 6.63%compared with the BCC-CSM and the linear observational constraint approach,respectively.The observational constraint correction prediction strategy with LightGBM significantly and stably improved the prediction of summer precipitation in China compared to the previous linear observational constraint solution,providing a reference for flood control and drought relief during the flood season(summer)in China.展开更多
Objective:To investigate the distribution of health literacy(HL)levels and the association of HL with proactive personality in patients with permanent colostomy.Methods:A cross-sectional study was conducted to measure...Objective:To investigate the distribution of health literacy(HL)levels and the association of HL with proactive personality in patients with permanent colostomy.Methods:A cross-sectional study was conducted to measure proactive personality and HL using validated scales.A total of 172 patients with permanent colostomy were selected from January 2021 to May 2022 in Yantai City,China.Descriptive statistics,t-test,ANOVA,Pearson correlation analysis,and multiple linear regression analysis techniques were used.Results:The results obtained from the study showed that the HL status of the participants was moderate.The correlation between participants’total HL scores and proactive personality scores was 0.417(P-value<0.001).In addition,HL showed statistically significant differences according to education level,place of residence,profession,and average monthly household income.Conclusions:This study showed that patients with higher proactive personality scores had higher HL.The key stakeholders require several positive strategies to improve the HL of patients with permanent colostomy by cultivating their proactive personalities,and these important policies will help to improve patient health and quality of life.展开更多
BACKGROUND Frailty is a complex aging-related syndrome characterized by a cumulative loss of physiological reserve and increased vulnerability to adverse clinical outcomes,including falls,disability,incapacity and dea...BACKGROUND Frailty is a complex aging-related syndrome characterized by a cumulative loss of physiological reserve and increased vulnerability to adverse clinical outcomes,including falls,disability,incapacity and death.While an increasing number of studies suggest that the gut microbiota may play a key role in the pathophy-siology of frailty,direct evaluation of the association between gut microbiome alterations and frailty in older adults remains limited.AIM Seven electronic databases(China National Knowledge Infrastructure,VIP,SinoMed,Wanfang,PubMed,Web of Science and EMBASE)were searched for articles published before October 31,2023 to identify observational studies that compared the microbiomes of older adults with and without frailty.The diversity and composition of the gut microbiota were the main outcomes used to analyze the associations of changes in the gut microbiota with frailty in older adults.The quality of the included studies was assessed via the Newcastle-Ottawa Scale and the Agency for Healthcare Research and Quality.RESULTS Eleven observational studies with 912 older adults were included in this review.Consistent results revealed a significant difference in the gut microbiota composition between frail and non-frail older adults,with a significant decrease inαdiversity and a significant increase inβdiversity in frail older adults.The pooled results revealed that at the phylum level,four microbiota(Actinobacteria,Proteo-bacteria,Verrucomicrobia and Synergistetes)were significantly enriched,and two microbiota(Firmicutes and Fusobacteria)were significantly depleted in frail older adults.At the family level,the results consistently revealed that the abundances of 6 families,most of which belong to the Actinobacteria or Proteo-bacteria phylum,were greater in frail than in non-frail older adults.At the genus or species level,consistent results from more than two studies revealed that the abundances of the genera Prevotella,Faecalibacterium,and Roseburia were significantly lower in frail older adults;individual studies revealed that the abundances of some genera or species(e.g.,Megamonas,Blautia,and Megasphaera)were significantly lower,whereas those of other genera or species(e.g.,Bifidobacterium,Oscillospira,Ruminococcus and Pyramidobacter)were significantly greater in frail older adults.CONCLUSION This systematic review suggests that changes in the gut microbiota are associated with frailty in older adults,which is commonly reflected by a reduction in beneficial species and an increase in pathogenic species.However,further studies are needed to confirm these findings.展开更多
Objective:To determine the efficacy and safety of the Yinmei Kuijie decoction combined with 5-ami-nosalicylic acid(5-ASA)in treating mildly to moderately active ulcerative colitis(UC)under real-world conditions.Method...Objective:To determine the efficacy and safety of the Yinmei Kuijie decoction combined with 5-ami-nosalicylic acid(5-ASA)in treating mildly to moderately active ulcerative colitis(UC)under real-world conditions.Methods:This multicenter,prospective,non-randomized,observational study will be conducted in real-world settings.A total of 204 eligible patients will be consecutively enrolled in the study.Patients in the combination treatment group will receive Yinmei Kuijie decoction in combination with 5-ASA,whereas those in the control group will be treated with 5-ASA alone.The primary endpoint will be a clinical response at week 12,defined as a≥3 point and≥30%reduction from baseline in the Mayo total score with≥1 reduction in rectal bleeding or rectal bleeding score=0 or 1.Secondary efficacy endpoints at week 12 will include health-related quality of life,mucosal healing,and inflammation indicators.Conclusion:The results of this study may provide evidence of the efficacy and safety of Yinmei Kuijie decoction combined with 5-ASA in treating patients with mildly to moderately active UC under real-world principles.The results will provide a basis for further confirmatory studies on the efficacy of Yinmei Kuijie decoction.展开更多
Dear Editor,Ensuring an appropriate response to external stimuli is essential for animals'survival and evolution.Research indicates that such stimuli can affect animals'physiological state and hormone levels,i...Dear Editor,Ensuring an appropriate response to external stimuli is essential for animals'survival and evolution.Research indicates that such stimuli can affect animals'physiological state and hormone levels,including corticosterone(CORT)[1,2].The impact of these stimuli on animals'performance depends on their density and duration,as they can either facilitate or hinder performance.While chronic and intense stressors can have detrimental effects on animals'physiological health and behavioral performance,leading to psychiatric disorders such as depression,anxiety,and schizophrenia[3],the effects of acute and mild observational stimuli are still unclear.展开更多
In this work, we consider the so-called Λ(α)CDM cosmology with Λ∝α^(-6) while the fine-structure"constant" α is varying. In this scenario, the accelerated expansion of the universe is driven by the cos...In this work, we consider the so-called Λ(α)CDM cosmology with Λ∝α^(-6) while the fine-structure"constant" α is varying. In this scenario, the accelerated expansion of the universe is driven by the cosmological"constant" Λ(equivalently the vacuum energy), and the varying α is driven by a subdominant scalar field ? coupling with the electromagnetic field. The observational constraints on the varying α and Λ∝α^(-6) models with various couplings BF(?) between the subdominant scalar field ? and the electromagnetic field are considered.展开更多
Fine measurements have been conducted to temperatures and their gradients of six wells of the Jinsha River Groundwater Observational Network.The results show that the influence depths of sun radiation heat are 50m to ...Fine measurements have been conducted to temperatures and their gradients of six wells of the Jinsha River Groundwater Observational Network.The results show that the influence depths of sun radiation heat are 50m to 125m,average temperature gradients in the wells range from 0.11 to 2.81℃/hm and most are 1~2℃/hm,and the temperature gradients on varied depth sections of one well are highly changeable.Lithology of strata and their integrity,particularly high-angle crashed fault zones,have imposed major effects on the influence depths of sun radiation heat and temperature gradients of the wells.The micro dynamic characteristics of water temperature,such as coseismic effects,tidal effects and anomalies of the wells prior to earthquakes,probably depend,to a large degree,on the temperature gradients of the depths at which the water temperature sensors are settled.展开更多
Using atmospheric observational data from 1998 to 2013,station rainfall data,TRMM(Tropical Rainfall Measuring Mission) data,as well as annual statistics for the plateau vortex and shear line,the joint activity featu...Using atmospheric observational data from 1998 to 2013,station rainfall data,TRMM(Tropical Rainfall Measuring Mission) data,as well as annual statistics for the plateau vortex and shear line,the joint activity features of sustained departure plateau vortexes(SDPVs) and southwest vortexes(SWVs) are analyzed.Some new and useful observational facts and understanding are obtained about the joint activities of the two types of vortex.The results show that:(1) The joint active period of the two vortexes is from May to August,and mostly in June and July.(2) The SDPVs of the partnership mainly originate near Zaduo,while the SWVs come from Jiulong.(3) Most of the two vortexes move in almost the same direction,moving eastward together with the low trough.The SDPVs mainly act in the area to the north of the Yangtze River,while the SWVs are situated across the Yangtze River valley.(4) The joint activity of the two vortexes often produces sustained regional heavy rainfall to the south of the Yellow River,influencing wide areas of China,and even as far as the Korean Peninsula,Japan and Vietnam.(5) Most of the two vortexes are baroclinic or cold vortexes,and they both become strengthened in terms of their joint activity.(6) When the two vortexes move over the sea,their central pressure descends and their rainfall increases,especially for SWVs.(7) The two vortexes might spin over the same area simultaneously when there are tropical cyclones in the eastern and southern seas of China,or move southward together if a tropical cyclone appears near Hainan Island.展开更多
Ischemic stroke is a devastating,life altering event which can severely reduce patient quality of life.Despite years of research there have been minimal therapeutic advances.Endothelial progenitor cells(EPCs),stem cel...Ischemic stroke is a devastating,life altering event which can severely reduce patient quality of life.Despite years of research there have been minimal therapeutic advances.Endothelial progenitor cells(EPCs),stem cells involved in both vasculogenesis and angiogenesis,may be a potential therapeutic target.After a stroke,EPCs migrate to the site of ischemic injury to repair cerebrovascular damage,and their numbers and functional capacity may determine patients'outcome.This study aims to determine whether the number of circulating EPCs and their functional aspects may be used as biomarkers to identify the type(cortical or lacunar)and/or severity of ischemic stroke.The study will also investigate if there are any differences in these characteristics between healthy volunteers over and under 65 years of age.100 stroke patients(50 lacunar and 50 cortical strokes)will be recruited in this prospective,observational case-controlled study.Blood samples will be taken from stroke patients at baseline(within 48 hours of stroke)and days 7,30 and90.EPCs will be counted with flow cytometry.The plasma levels of pro-and anti-angiogenic factors and inflammatory cytokines will also be determined.Outgrowth endothelial cells will be cultured to be used in tube formation,migration and proliferation functional assays.Primary outcome is disability or dependence on day 90 after stroke,assessed by the modified Rankin Scale.Secondary outcomes are changes in circulating EPC numbers and/or functional capacity between patient and healthy volunteers,between patient subgroups and between elderly and young healthy volunteers.Recruitment started in February 2017,167 participants have been recruited.Recruitment will end in November 2019.West Midlands-Coventry&Warwickshire Research Ethics Committee approved this study(REC number:16/WM/0304)on September8,2016.Protocol version:2.0.The Bayraktutan Dunhill Medical Trust EPC Study was registered in ClinicalTrials.gov(NCT02980354)on November 15,2016.This study will determine whether the number of EPCs can be used as a prognostic or diagnostic marker for ischemic strokes and is a step towards discovering if transplantation of EPCs may aid patient recovery.展开更多
AIM: To investigate if there is an association between hepatitis B virus (HBV) or hepatitis C virus (HCV) infection and the risk of pancreatic cancer. METHODS: All relevant studies published before 11 October, 2012 we...AIM: To investigate if there is an association between hepatitis B virus (HBV) or hepatitis C virus (HCV) infection and the risk of pancreatic cancer. METHODS: All relevant studies published before 11 October, 2012 were identified by a systematic search of MEDLINE, EMBASE, BIOSIS Previews and the Cochrane Library databases and with cross-referencing. The observational studies that reported RR or OR estimates with 95%CIs for the association between HBV or HCV and pancreatic cancer were included. A random-effects model was used to summarize meta-analytic estimates. The Newcastle-Ottawa quality assessment scale was applied to assess the quality of the methodology in the included studies. RESULTS: A total of 8 eligible studies were selected for meta-analysis. Overall, chronic hepatitis B and inactive hepatitis B surface antigen (HBsAg) carrier state (HBsAg positive) had a significantly increased risk of pancreatic cancer with OR of 1.20 (95%CI: 1.01-1.39), especially in the Chinese population (OR = 1.30, 95%CI: 1.05-1.56). Past exposure to HBV (possible occult HBV infection) had an increased OR of pancreatic cancer risk (OR = 1.24, 95%CI: 1.05-1.42), especially among those patients without natural immunity [anti hepatitis B core (HBc) positive/hepatitis B surface antibody (anti HBs) negative], with OR of 1.67 (95%CI: 1.13-2.22). However, past exposure to HBV with natural immunity (anti-HBc positive/anti-HBs positive) had no association with pancreatic cancer development, with OR 0.98 (95%CI: 0.80-1.16), nor did the HBV active replication (hepatitis B e antigen positive status), with OR 0.98 (95%CI: 0.27-1.68). The risk of pancreatic cancer among anti-HBs positive patients was significantly lower than among anti-HBs negative patients (OR = 0.54, 95%CI: 0.46-0.62). Past exposure to HCV also resulted in an increased risk of pancreatic cancer (OR = 1.26, 95%CI: 1.03-1.50). Significant between-study heterogeneity was observed. Evidence of publication bias for HBV/HCV infection-pancreatic cancer association was not found. CONCLUSION: Chronic HBV and HCV infection increases pancreatic cancer risk. Our findings underscore the need for more studies to confirm this potential relationship.展开更多
Features of structure and propagation of the 30 to SO day atmospheric oscillations are investigated using the ECMWF analysis of 1980-1983. Evidence is provided to confirm the characteristics of the oscillation in the ...Features of structure and propagation of the 30 to SO day atmospheric oscillations are investigated using the ECMWF analysis of 1980-1983. Evidence is provided to confirm the characteristics of the oscillation in the equatorial region. Those in the mid-high latitudes, however, are revealed to be very different from the tropics and pose a strong barotropic structure. Horizontal coherence shows teleconnection patterns which can be identified as EAP and PNA. The wind field of the specified time scale of the oscillation appears as long-lived vortices and vortex pairs. Mid-latitude perturbations propagate clearly westwards, especially during the winter season. In the high latitudes, they propagate westwards in the winter but eastwards in the summer. Meridional propagations are rather different from region to region.展开更多
Based on the long-term marine ship observation data, records of meteorological stations and High-Reflective Cloud(HRC) data by satellite remote sensing , this paper has studied the circulation patterns and variability...Based on the long-term marine ship observation data, records of meteorological stations and High-Reflective Cloud(HRC) data by satellite remote sensing , this paper has studied the circulation patterns and variability in elements during onset and the established periods of the South China Sea(SCS) southwest(SW) monsoon. The averaged date of the onset SW monsoon in the SCS occurs in the middle of May climatologically. The corresponding date for the northern part is little earlier (May 12) and those for the southern parts are little later (May 20). The interannual range of the onset dates is about one month. Following the onset of the SW monsoon, the cloud amount and the precipitation increase while the convection activities enhance over the SCS. But there is a strong spatial heterogeneity within the domain. After onset of the SW monsoon the strong convective area moves northwards, while the SCS rain band moves to the center and north. Sea surface temperature(SST) increases rapidly before the onset and the leading time is about one month. The increment of SST supplies heat and vapor for the onset. From April to May the surface heat fluxes display obvious changes, e.g., latent heat exchange and evaporation enhancement. It is one of the reasons why the SW monsoon bursts firstly in the SCS.展开更多
BACKGROUND Osteoporosis with vertebral compression fractures is increasingly common in the elderly population.Cement augmentation is one of the effective surgical treatments for these patients.Currently,there are seve...BACKGROUND Osteoporosis with vertebral compression fractures is increasingly common in the elderly population.Cement augmentation is one of the effective surgical treatments for these patients.Currently,there are several different types of cement augmentation treatments.No studies have compared the safety and efficacy of different cement augmentation types for the treatment of such fractures;thus,we retrospectively compared vertebroplasty,balloon kyphoplasty,and kyphoplasty with SpineJack or an intravertebral expandable pillar.AIM To compare the postoperative safety and efficacy of each surgical intervention in treating vertebral compression fractures.METHODS We retrospectively analyzed 354 patients with acute vertebral compression fractures,defined as signal changes in the T1 weighted magnetic resonance imaging,and randomly divided the patients into five groups.Their visual analog scale scores for pain,kyphotic angle,average body height,rate of cement leakage,and occurrence of adjacent vertebral compression fractures were followed for 1 year.One-way analysis of variance,the post hoc Bonferroni test,and Fisher exact probability test were used for statistical analyses.RESULTS All pain scores significantly improved 12 mo postoperatively;however,there was no significant difference between the groups(P=0.325).Kyphoplasty with SpineJack significantly reduced the kyphotic angle(P=0.028)and restored the height of the vertebral body(P=0.02).The rate of adjacent compression fractures was the highest in the vertebroplasty group,with a statistically significant difference according to the Fisher exact probability test(P=0.02).The treatment with the lowest cement leakage rate cannot be identified because of the small sample size;however,kyphoplasty with SpineJack,an IVEP,and vesselplasty resulted in lower rates of cement leakage than balloon kyphoplasty and vertebroplasty.CONCLUSION Kyphoplasty with SpineJack has good outcomes in kyphotic angle reduction and body height restoration.Vertebroplasty has the highest cement leakage rate and adjacent compression fracture occurrence.展开更多
In this part, the temporal evolution and interaction across the equator of 30-50 day oscillation in the atmosphere are investigated further. The annual variation of 30-50 day oscillation is quite obvious in the mid-hi...In this part, the temporal evolution and interaction across the equator of 30-50 day oscillation in the atmosphere are investigated further. The annual variation of 30-50 day oscillation is quite obvious in the mid-high latitudes. In the tropical atmosphere, the obvious interannual variation is an important property for temporal evolution of 30-50 day oscillation. The low-frequency wavetrain across the equator over the central Pacific and central Atlantic area, the movement of the long-lived low-frequency system across the equator and the meridional wind component across the equator will obviously show the interaction of 30-50 day oscillation in the atmosphere across the equator.展开更多
To estimate the true treatment effect on a censored outcome in observational studies, potential confounding effect and complex heterogeneity in the treatment assignment have to be properly adjusted. In this article, w...To estimate the true treatment effect on a censored outcome in observational studies, potential confounding effect and complex heterogeneity in the treatment assignment have to be properly adjusted. In this article, we demonstrate that the partial least squares method could be a valuable tool in this regard. It is showed that the partial least squares method not only can adequately account for the heterogeneity in treatment assignment, but also be robust to treatment assignment model misspecifications. Numerical results show that the partial least squares estimator is more efficient and robust. A real data set is analyzed to illustrate the proposed method.展开更多
The solar radio signal that can be received by the ground-based telescopes covers a wide frequency range,allowing us to monitor the complex physical processes occurred from the solar surface to the vast interplanetary...The solar radio signal that can be received by the ground-based telescopes covers a wide frequency range,allowing us to monitor the complex physical processes occurred from the solar surface to the vast interplanetary space.MingantU SpEctral Radioheliograph(MUSER),as the latest generation of solar dedicated radio spectral-imaging instrument in the centimeter-decimeter wavelengths,has accumulated a large number of observational data since its commissioning observation in 2014.This paper presents the main observational results identified by MUSER from 2014 to 2019,including the quiet Sun and 94 solar radio burst events.We find that there are 81 events accompanied with Geostationary Operational Environmental Satellites(GOES)soft X-ray(SXR)flares,among which the smallest flare class is B1.0.There are 13 events without accompanying any recorded flares,among which the smallest SXR intensity during the radio burst period is equivalent to level-A.The main characteristics of all radio burst events are presented,which shows the powerful ability of MUSER to capture the valuable information of the solar non-thermal processes and the importance for space weather.This work also provides a database for further in-depth research.展开更多
Aircraft Meteorological Data Relay(AMDAR)observations have been widely used in numerical weather prediction(NWP)because of its high spatiotemporal resolution.The observational error of AMDAR is influenced by aircraft ...Aircraft Meteorological Data Relay(AMDAR)observations have been widely used in numerical weather prediction(NWP)because of its high spatiotemporal resolution.The observational error of AMDAR is influenced by aircraft flight altitude and atmospheric condition.In this study,the wind speed and altitude dependent observational error of AMDAR is estimated.The statistical results show that the temperature and the observational error in wind speeds slightly decrease as altitude increases,and the observational error in wind speed increases as wind speed increases.Pseudo single AMDAR observation assimilation tests demonstrate that the wind speed and altitude dependent observational error can provide more reasonable analysis increment.Furthermore,to assess the performance of wind speed and altitude dependent observational error on data assimilation and forecasting,two-month 3-hourly cycling data assimilation and forecast experiments based on the Weather Research and Forecasting Model(WRF)and its Data Assimilation system(WRFDA)are performed for the period during 1 September-31 October,2017.The results of the two-month 3-hourly cycling experiments indicate that new observational error improves analysis and forecast of wind field and geo-potential height,and has slight improvements on temperature.The Fractions Skill Score(FSS)of the 6-h accumulated precipitation shows that new wind speed and altitude dependent observational error leads to better precipitation forecast skill than the default observational error in the WRFDA does.展开更多
To analyze the effects of gas cannons on clouds and precipitation,multisource observational data,including those from National Centers for Environmental Prediction(NCEP)reanalysis,Hangzhou and Huzhou new-generation we...To analyze the effects of gas cannons on clouds and precipitation,multisource observational data,including those from National Centers for Environmental Prediction(NCEP)reanalysis,Hangzhou and Huzhou new-generation weather radars,laser disdrometer,ground-based automatic weather station,wind profiler radar,and Lin'an C-band dualpolarization radar,were adopted in this study.Based on the variational dual-Doppler wind retrieval method and the polarimetric variables obtained by the dual-polarization radar,we analyzed the microphysical processes and the variations in the macro-and microphysical quantities in clouds from the perspective of the synoptic background before precipitation enhancement,the polarization echo characteristics before,during and after enhancement,and the evolution of the fine three-dimensional kinematic structure and the microphysical structure.The results show that the precipitation enhancement operation promoted the development of radar echoes and prolonged their duration,and both the horizontal and vertical wind speeds increased.The dual-polarization radar echo showed that the diameter of the precipitation particles increased,and the concentration of raindrops increased after precipitation enhancement.The raindrops were lifted to a height corresponding to 0 to-20℃due to vertical updrafts.Based on the disdrometer data during precipitation enhancement,the concentration of small raindrops(lgN_(w))showed a significant increase,and the mass-weighted diameter D_(m)value decreased,indicating that the precipitation enhancement operation played a certain“lubricating”effect.After the precipitation enhancement,the concentration of raindrops did not change much compared with that during the enhancement process,while the Dm increased,corresponding to an increase in rain intensity.The results suggest the positive effect of gas cannons on precipitation enhancement.展开更多
AIM:To evaluate whether red meat intake is related to the risk of endometrial cancer(EC) using meta-analysis.METHODS:We searched Pub Med,EMBASE,and the Cochrane Library up to June 2013,using common keywords related to...AIM:To evaluate whether red meat intake is related to the risk of endometrial cancer(EC) using meta-analysis.METHODS:We searched Pub Med,EMBASE,and the Cochrane Library up to June 2013,using common keywords related to red meat and EC.Case-control studies and cohort studies comparing the risk of endometrial cancer among categories by the amount of intake were included.Eleven case-control studies and five cohort studies met our criteria.We performed a conventional and a dose-response meta-analysis of case-control studies using the Der Simonian-Laird method for random-effects.For cohort studies we performed a conventional meta-analysis.Publication bias was evaluated using Egger's test.RESULTS:In the meta-analysis of 11 case-control studies including 5419 cases and 12654 controls,higher red meat consumption was associated with an increased risk of EC [summary relative risk(SRR) = 1.43,95%CI:1.15-1.79;I2 = 73.3% comparing extreme intake categories).In a dose-response analysis,for red meat intake of 100 g/d,SRR was 1.84(95%CI:1.64-2.05).In contrast,in the meta-analysis of five prospective studies including a total of 2549 cases among 247746 participants,no significant association between red meat intake and EC risk(SRR = 0.97,95%CI:0.85-1.11;I2 = 4.9% comparing extreme intake categories) was observed.CONCLUSION:Our meta-analysis found a significantlinear association between red meat intake and EC risk based on case-control studies but this was not confirmed in prospective studies.展开更多
基金supported by the China Postdoctoral Science Foundation(Grant No.2021M703366)Shenzhen Science and Technology Program(Grant No.KQTD20190929172835662).
文摘Objective Observational studies have found associations between inflammatory bowel disease(IBD)and the risk of dementia,including Alzheimer’s dementia(AD)and vascular dementia(VD);however,these findings are inconsistent.It remains unclear whether these associations are causal.Methods We conducted a meta-analysis by systematically searching for observational studies on the association between IBD and dementia.Mendelian randomization(MR)analysis based on summary genome-wide association studies(GWASs)was performed.Genetic correlation and Bayesian colocalization analyses were used to provide robust genetic evidence.Results Ten observational studies involving 80,565,688 participants were included in this metaanalysis.IBD was significantly associated with dementia(risk ratio[RR]=1.36,95%CI=1.04-1.78;I2=84.8%)and VD(RR=2.60,95%CI=1.18-5.70;only one study),but not with AD(RR=2.00,95%CI=0.96-4.13;I^(2)=99.8%).MR analyses did not supported significant causal associations of IBD with dementia(dementia:odds ratio[OR]=1.01,95%CI=0.98-1.03;AD:OR=0.98,95%CI=0.95-1.01;VD:OR=1.02,95%CI=0.97-1.07).In addition,genetic correlation and co-localization analyses did not reveal any genetic associations between IBD and dementia.Conclusion Our study did not provide genetic evidence for a causal association between IBD and dementia risk.The increased risk of dementia observed in observational studies may be attributed to unobserved confounding factors or detection bias.
基金jointly supported by the National Natural Science Foundation of China(Grant Nos.42122034,42075043,42330609)the Second Tibetan Plateau Scientific Expedition and Research program(2019QZKK0103)+2 种基金Key Talent Project in Gansu and Central Guidance Fund for Local Science and Technology Development Projects in Gansu(No.24ZYQA031)the Youth Innovation Promotion Association of Chinese Academy of Sciences(2021427)West Light Foundation of the Chinese Academy of Sciences(xbzg-zdsys-202215)。
文摘Seasonal precipitation has always been a key focus of climate prediction.As a dynamic-statistical combined method,the existing observational constraint correction establishes a regression relationship between the numerical model outputs and historical observations,which can partly predict seasonal precipitation.However,solving a nonlinear problem through linear regression is significantly biased.This study implements a nonlinear optimization of an existing observational constrained correction model using a Light Gradient Boosting Machine(LightGBM)machine learning algorithm based on output from the Beijing National Climate Center Climate System Model(BCC-CSM)and station observations to improve the prediction of summer precipitation in China.The model was trained using a rolling approach,and LightGBM outperformed Linear Regression(LR),Extreme Gradient Boosting(XGBoost),and Categorical Boosting(CatBoost).Using parameter tuning to optimize the machine learning model and predict future summer precipitation using eight different predictors in BCC-CSM,the mean Anomaly Correlation Coefficient(ACC)score in the 2019–22 summer precipitation predictions was 0.17,and the mean Prediction Score(PS)reached 74.The PS score was improved by 7.87%and 6.63%compared with the BCC-CSM and the linear observational constraint approach,respectively.The observational constraint correction prediction strategy with LightGBM significantly and stably improved the prediction of summer precipitation in China compared to the previous linear observational constraint solution,providing a reference for flood control and drought relief during the flood season(summer)in China.
文摘Objective:To investigate the distribution of health literacy(HL)levels and the association of HL with proactive personality in patients with permanent colostomy.Methods:A cross-sectional study was conducted to measure proactive personality and HL using validated scales.A total of 172 patients with permanent colostomy were selected from January 2021 to May 2022 in Yantai City,China.Descriptive statistics,t-test,ANOVA,Pearson correlation analysis,and multiple linear regression analysis techniques were used.Results:The results obtained from the study showed that the HL status of the participants was moderate.The correlation between participants’total HL scores and proactive personality scores was 0.417(P-value<0.001).In addition,HL showed statistically significant differences according to education level,place of residence,profession,and average monthly household income.Conclusions:This study showed that patients with higher proactive personality scores had higher HL.The key stakeholders require several positive strategies to improve the HL of patients with permanent colostomy by cultivating their proactive personalities,and these important policies will help to improve patient health and quality of life.
文摘BACKGROUND Frailty is a complex aging-related syndrome characterized by a cumulative loss of physiological reserve and increased vulnerability to adverse clinical outcomes,including falls,disability,incapacity and death.While an increasing number of studies suggest that the gut microbiota may play a key role in the pathophy-siology of frailty,direct evaluation of the association between gut microbiome alterations and frailty in older adults remains limited.AIM Seven electronic databases(China National Knowledge Infrastructure,VIP,SinoMed,Wanfang,PubMed,Web of Science and EMBASE)were searched for articles published before October 31,2023 to identify observational studies that compared the microbiomes of older adults with and without frailty.The diversity and composition of the gut microbiota were the main outcomes used to analyze the associations of changes in the gut microbiota with frailty in older adults.The quality of the included studies was assessed via the Newcastle-Ottawa Scale and the Agency for Healthcare Research and Quality.RESULTS Eleven observational studies with 912 older adults were included in this review.Consistent results revealed a significant difference in the gut microbiota composition between frail and non-frail older adults,with a significant decrease inαdiversity and a significant increase inβdiversity in frail older adults.The pooled results revealed that at the phylum level,four microbiota(Actinobacteria,Proteo-bacteria,Verrucomicrobia and Synergistetes)were significantly enriched,and two microbiota(Firmicutes and Fusobacteria)were significantly depleted in frail older adults.At the family level,the results consistently revealed that the abundances of 6 families,most of which belong to the Actinobacteria or Proteo-bacteria phylum,were greater in frail than in non-frail older adults.At the genus or species level,consistent results from more than two studies revealed that the abundances of the genera Prevotella,Faecalibacterium,and Roseburia were significantly lower in frail older adults;individual studies revealed that the abundances of some genera or species(e.g.,Megamonas,Blautia,and Megasphaera)were significantly lower,whereas those of other genera or species(e.g.,Bifidobacterium,Oscillospira,Ruminococcus and Pyramidobacter)were significantly greater in frail older adults.CONCLUSION This systematic review suggests that changes in the gut microbiota are associated with frailty in older adults,which is commonly reflected by a reduction in beneficial species and an increase in pathogenic species.However,further studies are needed to confirm these findings.
基金supported by the Key Project of Traditional Chinese Medicine in Anhui Province(202303a07020003)Basic Research Expenses of Beijing University of Chinese Medicine(2024-JYB-JBZD-044)Vertical Development Fund of Beijing University of Chinese Medicine(2023-ZXFZJJ-005).
文摘Objective:To determine the efficacy and safety of the Yinmei Kuijie decoction combined with 5-ami-nosalicylic acid(5-ASA)in treating mildly to moderately active ulcerative colitis(UC)under real-world conditions.Methods:This multicenter,prospective,non-randomized,observational study will be conducted in real-world settings.A total of 204 eligible patients will be consecutively enrolled in the study.Patients in the combination treatment group will receive Yinmei Kuijie decoction in combination with 5-ASA,whereas those in the control group will be treated with 5-ASA alone.The primary endpoint will be a clinical response at week 12,defined as a≥3 point and≥30%reduction from baseline in the Mayo total score with≥1 reduction in rectal bleeding or rectal bleeding score=0 or 1.Secondary efficacy endpoints at week 12 will include health-related quality of life,mucosal healing,and inflammation indicators.Conclusion:The results of this study may provide evidence of the efficacy and safety of Yinmei Kuijie decoction combined with 5-ASA in treating patients with mildly to moderately active UC under real-world principles.The results will provide a basis for further confirmatory studies on the efficacy of Yinmei Kuijie decoction.
基金supported by the National Natural Science Foundation of China and Guangdong Province Joint Fund (U20A6005)。
文摘Dear Editor,Ensuring an appropriate response to external stimuli is essential for animals'survival and evolution.Research indicates that such stimuli can affect animals'physiological state and hormone levels,including corticosterone(CORT)[1,2].The impact of these stimuli on animals'performance depends on their density and duration,as they can either facilitate or hinder performance.While chronic and intense stressors can have detrimental effects on animals'physiological health and behavioral performance,leading to psychiatric disorders such as depression,anxiety,and schizophrenia[3],the effects of acute and mild observational stimuli are still unclear.
基金Supported by the National Natural Science Foundation of China under Grant Nos.11575022 and 11175016
文摘In this work, we consider the so-called Λ(α)CDM cosmology with Λ∝α^(-6) while the fine-structure"constant" α is varying. In this scenario, the accelerated expansion of the universe is driven by the cosmological"constant" Λ(equivalently the vacuum energy), and the varying α is driven by a subdominant scalar field ? coupling with the electromagnetic field. The observational constraints on the varying α and Λ∝α^(-6) models with various couplings BF(?) between the subdominant scalar field ? and the electromagnetic field are considered.
基金supported by the Jinsha River Development Corporation Limited,China Yangtze Three Gorge Engineering Development Group(JSJ(06)-007)
文摘Fine measurements have been conducted to temperatures and their gradients of six wells of the Jinsha River Groundwater Observational Network.The results show that the influence depths of sun radiation heat are 50m to 125m,average temperature gradients in the wells range from 0.11 to 2.81℃/hm and most are 1~2℃/hm,and the temperature gradients on varied depth sections of one well are highly changeable.Lithology of strata and their integrity,particularly high-angle crashed fault zones,have imposed major effects on the influence depths of sun radiation heat and temperature gradients of the wells.The micro dynamic characteristics of water temperature,such as coseismic effects,tidal effects and anomalies of the wells prior to earthquakes,probably depend,to a large degree,on the temperature gradients of the depths at which the water temperature sensors are settled.
基金supported by project funds from the National Natural Science Foundation of China(Grant Nos.91332715 and 41275052)the National Key Foundation Development Study Developing(973)Programme(Grant No.2012CB417202)
文摘Using atmospheric observational data from 1998 to 2013,station rainfall data,TRMM(Tropical Rainfall Measuring Mission) data,as well as annual statistics for the plateau vortex and shear line,the joint activity features of sustained departure plateau vortexes(SDPVs) and southwest vortexes(SWVs) are analyzed.Some new and useful observational facts and understanding are obtained about the joint activities of the two types of vortex.The results show that:(1) The joint active period of the two vortexes is from May to August,and mostly in June and July.(2) The SDPVs of the partnership mainly originate near Zaduo,while the SWVs come from Jiulong.(3) Most of the two vortexes move in almost the same direction,moving eastward together with the low trough.The SDPVs mainly act in the area to the north of the Yangtze River,while the SWVs are situated across the Yangtze River valley.(4) The joint activity of the two vortexes often produces sustained regional heavy rainfall to the south of the Yellow River,influencing wide areas of China,and even as far as the Korean Peninsula,Japan and Vietnam.(5) Most of the two vortexes are baroclinic or cold vortexes,and they both become strengthened in terms of their joint activity.(6) When the two vortexes move over the sea,their central pressure descends and their rainfall increases,especially for SWVs.(7) The two vortexes might spin over the same area simultaneously when there are tropical cyclones in the eastern and southern seas of China,or move southward together if a tropical cyclone appears near Hainan Island.
基金supported by a grant to Dr Ulvi Bayraktutan from The Dunhill Medical Trust(R459/0216)
文摘Ischemic stroke is a devastating,life altering event which can severely reduce patient quality of life.Despite years of research there have been minimal therapeutic advances.Endothelial progenitor cells(EPCs),stem cells involved in both vasculogenesis and angiogenesis,may be a potential therapeutic target.After a stroke,EPCs migrate to the site of ischemic injury to repair cerebrovascular damage,and their numbers and functional capacity may determine patients'outcome.This study aims to determine whether the number of circulating EPCs and their functional aspects may be used as biomarkers to identify the type(cortical or lacunar)and/or severity of ischemic stroke.The study will also investigate if there are any differences in these characteristics between healthy volunteers over and under 65 years of age.100 stroke patients(50 lacunar and 50 cortical strokes)will be recruited in this prospective,observational case-controlled study.Blood samples will be taken from stroke patients at baseline(within 48 hours of stroke)and days 7,30 and90.EPCs will be counted with flow cytometry.The plasma levels of pro-and anti-angiogenic factors and inflammatory cytokines will also be determined.Outgrowth endothelial cells will be cultured to be used in tube formation,migration and proliferation functional assays.Primary outcome is disability or dependence on day 90 after stroke,assessed by the modified Rankin Scale.Secondary outcomes are changes in circulating EPC numbers and/or functional capacity between patient and healthy volunteers,between patient subgroups and between elderly and young healthy volunteers.Recruitment started in February 2017,167 participants have been recruited.Recruitment will end in November 2019.West Midlands-Coventry&Warwickshire Research Ethics Committee approved this study(REC number:16/WM/0304)on September8,2016.Protocol version:2.0.The Bayraktutan Dunhill Medical Trust EPC Study was registered in ClinicalTrials.gov(NCT02980354)on November 15,2016.This study will determine whether the number of EPCs can be used as a prognostic or diagnostic marker for ischemic strokes and is a step towards discovering if transplantation of EPCs may aid patient recovery.
基金Supported by International Cooperation Project of the Guangzhou Science and Technology Bureau, No. 2011J5200017Guangdong Provincial Science and Technology Development Program, No. 2011B031800207
文摘AIM: To investigate if there is an association between hepatitis B virus (HBV) or hepatitis C virus (HCV) infection and the risk of pancreatic cancer. METHODS: All relevant studies published before 11 October, 2012 were identified by a systematic search of MEDLINE, EMBASE, BIOSIS Previews and the Cochrane Library databases and with cross-referencing. The observational studies that reported RR or OR estimates with 95%CIs for the association between HBV or HCV and pancreatic cancer were included. A random-effects model was used to summarize meta-analytic estimates. The Newcastle-Ottawa quality assessment scale was applied to assess the quality of the methodology in the included studies. RESULTS: A total of 8 eligible studies were selected for meta-analysis. Overall, chronic hepatitis B and inactive hepatitis B surface antigen (HBsAg) carrier state (HBsAg positive) had a significantly increased risk of pancreatic cancer with OR of 1.20 (95%CI: 1.01-1.39), especially in the Chinese population (OR = 1.30, 95%CI: 1.05-1.56). Past exposure to HBV (possible occult HBV infection) had an increased OR of pancreatic cancer risk (OR = 1.24, 95%CI: 1.05-1.42), especially among those patients without natural immunity [anti hepatitis B core (HBc) positive/hepatitis B surface antibody (anti HBs) negative], with OR of 1.67 (95%CI: 1.13-2.22). However, past exposure to HBV with natural immunity (anti-HBc positive/anti-HBs positive) had no association with pancreatic cancer development, with OR 0.98 (95%CI: 0.80-1.16), nor did the HBV active replication (hepatitis B e antigen positive status), with OR 0.98 (95%CI: 0.27-1.68). The risk of pancreatic cancer among anti-HBs positive patients was significantly lower than among anti-HBs negative patients (OR = 0.54, 95%CI: 0.46-0.62). Past exposure to HCV also resulted in an increased risk of pancreatic cancer (OR = 1.26, 95%CI: 1.03-1.50). Significant between-study heterogeneity was observed. Evidence of publication bias for HBV/HCV infection-pancreatic cancer association was not found. CONCLUSION: Chronic HBV and HCV infection increases pancreatic cancer risk. Our findings underscore the need for more studies to confirm this potential relationship.
文摘Features of structure and propagation of the 30 to SO day atmospheric oscillations are investigated using the ECMWF analysis of 1980-1983. Evidence is provided to confirm the characteristics of the oscillation in the equatorial region. Those in the mid-high latitudes, however, are revealed to be very different from the tropics and pose a strong barotropic structure. Horizontal coherence shows teleconnection patterns which can be identified as EAP and PNA. The wind field of the specified time scale of the oscillation appears as long-lived vortices and vortex pairs. Mid-latitude perturbations propagate clearly westwards, especially during the winter season. In the high latitudes, they propagate westwards in the winter but eastwards in the summer. Meridional propagations are rather different from region to region.
文摘Based on the long-term marine ship observation data, records of meteorological stations and High-Reflective Cloud(HRC) data by satellite remote sensing , this paper has studied the circulation patterns and variability in elements during onset and the established periods of the South China Sea(SCS) southwest(SW) monsoon. The averaged date of the onset SW monsoon in the SCS occurs in the middle of May climatologically. The corresponding date for the northern part is little earlier (May 12) and those for the southern parts are little later (May 20). The interannual range of the onset dates is about one month. Following the onset of the SW monsoon, the cloud amount and the precipitation increase while the convection activities enhance over the SCS. But there is a strong spatial heterogeneity within the domain. After onset of the SW monsoon the strong convective area moves northwards, while the SCS rain band moves to the center and north. Sea surface temperature(SST) increases rapidly before the onset and the leading time is about one month. The increment of SST supplies heat and vapor for the onset. From April to May the surface heat fluxes display obvious changes, e.g., latent heat exchange and evaporation enhancement. It is one of the reasons why the SW monsoon bursts firstly in the SCS.
文摘BACKGROUND Osteoporosis with vertebral compression fractures is increasingly common in the elderly population.Cement augmentation is one of the effective surgical treatments for these patients.Currently,there are several different types of cement augmentation treatments.No studies have compared the safety and efficacy of different cement augmentation types for the treatment of such fractures;thus,we retrospectively compared vertebroplasty,balloon kyphoplasty,and kyphoplasty with SpineJack or an intravertebral expandable pillar.AIM To compare the postoperative safety and efficacy of each surgical intervention in treating vertebral compression fractures.METHODS We retrospectively analyzed 354 patients with acute vertebral compression fractures,defined as signal changes in the T1 weighted magnetic resonance imaging,and randomly divided the patients into five groups.Their visual analog scale scores for pain,kyphotic angle,average body height,rate of cement leakage,and occurrence of adjacent vertebral compression fractures were followed for 1 year.One-way analysis of variance,the post hoc Bonferroni test,and Fisher exact probability test were used for statistical analyses.RESULTS All pain scores significantly improved 12 mo postoperatively;however,there was no significant difference between the groups(P=0.325).Kyphoplasty with SpineJack significantly reduced the kyphotic angle(P=0.028)and restored the height of the vertebral body(P=0.02).The rate of adjacent compression fractures was the highest in the vertebroplasty group,with a statistically significant difference according to the Fisher exact probability test(P=0.02).The treatment with the lowest cement leakage rate cannot be identified because of the small sample size;however,kyphoplasty with SpineJack,an IVEP,and vesselplasty resulted in lower rates of cement leakage than balloon kyphoplasty and vertebroplasty.CONCLUSION Kyphoplasty with SpineJack has good outcomes in kyphotic angle reduction and body height restoration.Vertebroplasty has the highest cement leakage rate and adjacent compression fracture occurrence.
基金This study was supported in part by National Natural Science Foundation of China
文摘In this part, the temporal evolution and interaction across the equator of 30-50 day oscillation in the atmosphere are investigated further. The annual variation of 30-50 day oscillation is quite obvious in the mid-high latitudes. In the tropical atmosphere, the obvious interannual variation is an important property for temporal evolution of 30-50 day oscillation. The low-frequency wavetrain across the equator over the central Pacific and central Atlantic area, the movement of the long-lived low-frequency system across the equator and the meridional wind component across the equator will obviously show the interaction of 30-50 day oscillation in the atmosphere across the equator.
基金Supported by the National Natural Science Foundation of China(11501578,11701571)
文摘To estimate the true treatment effect on a censored outcome in observational studies, potential confounding effect and complex heterogeneity in the treatment assignment have to be properly adjusted. In this article, we demonstrate that the partial least squares method could be a valuable tool in this regard. It is showed that the partial least squares method not only can adequately account for the heterogeneity in treatment assignment, but also be robust to treatment assignment model misspecifications. Numerical results show that the partial least squares estimator is more efficient and robust. A real data set is analyzed to illustrate the proposed method.
基金supported by the National Natural Science Foundation of China (Grant Nos. 11790301, 11790305, 11973057, 12003048, 11903055, 11773043 and 12003049)supported by the Ministry of Science and Technology of China Key Project (2018YFA0404602)the international collaboration of ISSI-BJ
文摘The solar radio signal that can be received by the ground-based telescopes covers a wide frequency range,allowing us to monitor the complex physical processes occurred from the solar surface to the vast interplanetary space.MingantU SpEctral Radioheliograph(MUSER),as the latest generation of solar dedicated radio spectral-imaging instrument in the centimeter-decimeter wavelengths,has accumulated a large number of observational data since its commissioning observation in 2014.This paper presents the main observational results identified by MUSER from 2014 to 2019,including the quiet Sun and 94 solar radio burst events.We find that there are 81 events accompanied with Geostationary Operational Environmental Satellites(GOES)soft X-ray(SXR)flares,among which the smallest flare class is B1.0.There are 13 events without accompanying any recorded flares,among which the smallest SXR intensity during the radio burst period is equivalent to level-A.The main characteristics of all radio burst events are presented,which shows the powerful ability of MUSER to capture the valuable information of the solar non-thermal processes and the importance for space weather.This work also provides a database for further in-depth research.
基金National Key R&D Program of China(2017YFC1502102,2018YFC1506802)National Natural Science Foundation of China(41675102)。
文摘Aircraft Meteorological Data Relay(AMDAR)observations have been widely used in numerical weather prediction(NWP)because of its high spatiotemporal resolution.The observational error of AMDAR is influenced by aircraft flight altitude and atmospheric condition.In this study,the wind speed and altitude dependent observational error of AMDAR is estimated.The statistical results show that the temperature and the observational error in wind speeds slightly decrease as altitude increases,and the observational error in wind speed increases as wind speed increases.Pseudo single AMDAR observation assimilation tests demonstrate that the wind speed and altitude dependent observational error can provide more reasonable analysis increment.Furthermore,to assess the performance of wind speed and altitude dependent observational error on data assimilation and forecasting,two-month 3-hourly cycling data assimilation and forecast experiments based on the Weather Research and Forecasting Model(WRF)and its Data Assimilation system(WRFDA)are performed for the period during 1 September-31 October,2017.The results of the two-month 3-hourly cycling experiments indicate that new observational error improves analysis and forecast of wind field and geo-potential height,and has slight improvements on temperature.The Fractions Skill Score(FSS)of the 6-h accumulated precipitation shows that new wind speed and altitude dependent observational error leads to better precipitation forecast skill than the default observational error in the WRFDA does.
基金National Natural Science Foundation of China(41675029)Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX18_0998)+1 种基金Science and Technology Program of Huzhou(2021GZ14,2020GZ31)Science and Technology(Key)Program of Zhejiang Meteorological Service(2021ZD27)。
文摘To analyze the effects of gas cannons on clouds and precipitation,multisource observational data,including those from National Centers for Environmental Prediction(NCEP)reanalysis,Hangzhou and Huzhou new-generation weather radars,laser disdrometer,ground-based automatic weather station,wind profiler radar,and Lin'an C-band dualpolarization radar,were adopted in this study.Based on the variational dual-Doppler wind retrieval method and the polarimetric variables obtained by the dual-polarization radar,we analyzed the microphysical processes and the variations in the macro-and microphysical quantities in clouds from the perspective of the synoptic background before precipitation enhancement,the polarization echo characteristics before,during and after enhancement,and the evolution of the fine three-dimensional kinematic structure and the microphysical structure.The results show that the precipitation enhancement operation promoted the development of radar echoes and prolonged their duration,and both the horizontal and vertical wind speeds increased.The dual-polarization radar echo showed that the diameter of the precipitation particles increased,and the concentration of raindrops increased after precipitation enhancement.The raindrops were lifted to a height corresponding to 0 to-20℃due to vertical updrafts.Based on the disdrometer data during precipitation enhancement,the concentration of small raindrops(lgN_(w))showed a significant increase,and the mass-weighted diameter D_(m)value decreased,indicating that the precipitation enhancement operation played a certain“lubricating”effect.After the precipitation enhancement,the concentration of raindrops did not change much compared with that during the enhancement process,while the Dm increased,corresponding to an increase in rain intensity.The results suggest the positive effect of gas cannons on precipitation enhancement.
基金Supported by A grant of the Korean Health Technology R and D Project,Ministry of Health and Welfare,Republic of Korea,No.HI12C0050
文摘AIM:To evaluate whether red meat intake is related to the risk of endometrial cancer(EC) using meta-analysis.METHODS:We searched Pub Med,EMBASE,and the Cochrane Library up to June 2013,using common keywords related to red meat and EC.Case-control studies and cohort studies comparing the risk of endometrial cancer among categories by the amount of intake were included.Eleven case-control studies and five cohort studies met our criteria.We performed a conventional and a dose-response meta-analysis of case-control studies using the Der Simonian-Laird method for random-effects.For cohort studies we performed a conventional meta-analysis.Publication bias was evaluated using Egger's test.RESULTS:In the meta-analysis of 11 case-control studies including 5419 cases and 12654 controls,higher red meat consumption was associated with an increased risk of EC [summary relative risk(SRR) = 1.43,95%CI:1.15-1.79;I2 = 73.3% comparing extreme intake categories).In a dose-response analysis,for red meat intake of 100 g/d,SRR was 1.84(95%CI:1.64-2.05).In contrast,in the meta-analysis of five prospective studies including a total of 2549 cases among 247746 participants,no significant association between red meat intake and EC risk(SRR = 0.97,95%CI:0.85-1.11;I2 = 4.9% comparing extreme intake categories) was observed.CONCLUSION:Our meta-analysis found a significantlinear association between red meat intake and EC risk based on case-control studies but this was not confirmed in prospective studies.