Lag effect

滞后效应
  • 文章类型: Journal Article
    血吸虫病是一种重大的公共卫生威胁,钉螺是日本血吸虫的唯一中间宿主。我们进行了为期12年的月度重复调查,以探索环境因素对蜗牛密度的交互和滞后效应,并监测其在中国洞庭湖地区的长期和季节性趋势。相关环境数据来自多个来源。构建了贝叶斯核机回归模型和贝叶斯时间模型结合分布滞后模型,分析了环境因素对蜗牛密度的交互效应和滞后效应。结果表明,研究地点的年平均蜗牛密度呈先增加后减少的趋势,在2013年达到顶峰。蜗牛密度在10月份最高,在1月份最低。归一化植被指数(NDVI)和水位是蜗牛密度的最有效预测因子,温度之间潜在的相互作用,降水,NDVI一月份的平均最低气温,水位,在1至4个月的滞后时间内,降水和NDVI与蜗牛密度呈正相关。这些研究结果可为有关部门监测蜗牛密度变化趋势及实施控制措施提供参考,从而减少血吸虫病的发生。
    Schistosomiasis is a significant public health threat, and Oncomelania hupensis is the only intermediate host for schistosoma japonicum. We conducted 12-year monthly repeated surveys to explore the interactive and lag effects of environmental factors on snail density and to monitor their long-term and seasonal trends in a bottomland around the Dongting Lake region in China. Relevant environmental data were obtained from multiple sources. A Bayesian kernel machine regression model and a Bayesian temporal model combined with a distributed lag model were constructed to analyze interactive and lag effects of environmental factors on snail density. The results indicated the average annual snail density in the study site exhibited an increasing and then decreasing trend, peaking in 2013. Snail densities were the highest in October and the lowest in January in a year. Normalized Difference Vegetation Index (NDVI) and water level were the most effective predictors of snail density, with potential interactions among temperature, precipitation, and NDVI. The mean minimum temperature in January, water level, precipitation and NDVI were positively correlated with snail density at lags ranging from 1 to 4 months. These findings could serve as references for relevant authorities to monitor the changing trend of snail density and implement control measures, thereby reducing the occurrence of schistosomiasis.
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  • 文章类型: Journal Article
    细颗粒物(PM2.5)是心血管疾病的危险因素。PM2.5成分与心血管疾病之间的关联是一个特别感兴趣的点,但不一致。本研究旨在探讨PM2.5中重金属(类)成分对心血管的影响。死亡率数据,安阳市大气污染物和气象因素,收集了2017年至2021年的中国。每月对PM2.5中的重金属(类)进行监测和检查。将案例交叉设计应用于估计数据集。镉(Cd)的四分位数间距增加,滞后1的锑(Sb)和砷(As)与8.1%的增量相关(95%CI:3.3,13.2),4.8%(95%CI:0.2,9.5)和3.5%(95%CI:1.1,6.0)心血管死亡率。滞后2期硒与脑血管死亡率呈负相关(RR=0.92095%CI:0.862,0.983)。当日铝暴露与缺血性心脏病死亡率呈正相关(RR=1.08395%CI:1.001,1.172)。分层分析表明性别,年龄和季节改变了As对心血管的影响(P<0.05)。我们的研究表明,重金属(类)在PM2.5的不利影响中起关键作用。Cd,Sb和As是心血管死亡的重要危险因素。这些发现对准确控制和管理空气污染物以改善公共卫生效益具有潜在意义。
    Fine particulate matter (PM2.5) is a risk factor of cardiovascular disease. Associations between PM2.5 compositions and cardiovascular disease are a point of special interest but inconsistent. This study aimed to explore the cardiovascular effects of heavy metal(loid) compositions in PM2.5. Data for mortality, air pollutants and meteorological factors in Anyang, China from 2017 to 2021 were collected. Heavy metal(loid) in PM2.5 were monitored and examined monthly. A Case-crossover design was applied to the estimated data set. The interquartile range increase in cadmium (Cd), antimony (Sb) and arsenic (As) at lag 1 was associated with increment of 8.1% (95% CI: 3.3, 13.2), 4.8% (95% CI: 0.2, 9.5) and 3.5% (95% CI: 1.1, 6.0) cardiovascular mortality. Selenium in lag 2 was inversely associated with cerebrovascular mortality (RR = 0.920 95% CI: 0.862, 0.983). Current-day exposure of aluminum was positively associated with mortality from ischemic heart disease (RR = 1.083 95% CI: 1.001, 1.172). Stratified analysis indicated sex, age and season modified the cardiovascular effects of As (P < 0.05). Our study reveals that heavy metal(loid) play key roles in adverse effects of PM2.5. Cd, Sb and As were significant risk factors of cardiovascular mortality. These findings have potential implications for accurate air pollutants control and management to improve public health benefits.
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  • 文章类型: Journal Article
    温度变化对心血管疾病的不利影响。然而,体温变化与冠状动脉疾病(CAD)之间的关系尚不明确.本研究旨在探讨中国东南沿海(福州市)每日平均温度与每日CAD住院人数之间的关系。
    共获得了1883名在2017年至2019年间接受经皮冠状动脉介入治疗的CAD患者。通过Gensini评分评价CAD的严重程度。使用分布式滞后非线性模型(DLNM)结合准泊松回归模型来检查每日平均温度与每日CAD住院人数之间的延迟效应。通过Gensini评分和病变严重程度进行分层分析。使用具有95%置信区间(CI)的相对风险(RR)来评估这种关系。
    极端寒冷(8°C)(RR=0.49,95%CI:0.25-0.99)和中度寒冷(10°C)(RR=0.56,95%CI:0.31-0.99)的每日平均温度滞后0-20天与每日CAD住院风险较低相关。中热(30°C)(RR=1.80,95%CI:1.01-3.20)和极热(32°C)(RR=2.02,95%CI:1.01-4.04)日平均温度,滞后0-20天与每日CAD住院风险较高有关。对于每日平均温度观察到类似的结果,滞后0-25天。分层分析显示,每日平均温度(滞后0、0-5、0-15、0-20和0-25天)对每日冠心病住院患者的滞后效应仅在Gensini评分≤39(三分1)的患者中观察到。
    寒冷的温度可能对福州地区的CAD医院的日常入院有保护作用,而高温会产生不利影响。
    UNASSIGNED: Temperature changes unfavorably impact on cardiovascular disease. However, the association between temperature changes and coronary artery disease (CAD) is not well documented. This study aimed to explore the association between daily mean temperature and daily CAD hospital admissions on the southeast coast of China (Fuzhou City).
    UNASSIGNED: A total of 1883 CAD patients who underwent percutaneous coronary intervention between 2017 and 2019 were obtained. The severity of CAD was evaluated by the Gensini score. Distributed lag non-linear model (DLNM) combined with a quasi-Poisson regression model was used to examine the delayed effect between daily mean temperature and daily CAD hospital admissions. Stratified analyses were performed by Gensini score and severity of lesions. The relative risk (RR) with a 95% confidence interval (CI) was used to assess the relationship.
    UNASSIGNED: Extreme cold (8°C) (RR=0.49, 95% CI: 0.25-0.99) and moderate cold (10°C) (RR=0.56, 95% CI: 0.31-0.99) daily mean temperature with a lag of 0-20 days were correlated with lower risk of daily CAD hospital admissions. Moderate heat (30°C) (RR=1.80, 95% CI: 1.01-3.20) and extreme heat (32°C) (RR=2.02, 95% CI: 1.01-4.04) daily mean temperature with a lag of 0-20 days related to a higher risk of daily CAD hospital admissions. Similar results were observed for daily mean temperature with a lag of 0-25 days. Stratified analysis showed the lagged effect of daily mean temperature (lag 0, 0-5, 0-15, 0-20, and 0-25 days) on the daily CAD hospital admissions was observed only in patients with a Gensini score ≤39 (tertile 1).
    UNASSIGNED: Cold temperatures may have a protective effect on daily CAD hospital admissions in the Fuzhou area, whereas hot temperatures can have an adverse effect.
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  • 文章类型: Journal Article
    由沼泽附近的枯树组成的幽灵森林是气候变化的惊人指标,面对全球海平面上升,沼泽向后退的沿海森林迁移是沼泽生存的主要机制。沿海海侵模型通常假设静态地形被淹没,并且随着海平面上升,森林立即转化为沼泽。相比之下,在这里,我们使用四十年的卫星观测表明,尽管经历了地球上最快的相对海平面上升速度(RSLRR),但美国中大西洋沿岸的许多低海拔森林仍得以幸存。横向森林退缩率受到地形和海水盐度的强烈影响,但不能直接用RSLRR的空间变异性来解释,气候,或干扰。沿海树木线的海拔以与以下相关的速率向上倾斜。但远远低于,当代RSLRR。一起,这些发现表明,RSLRR和土地转换之间存在年代际滞后,这意味着沿海生态系统的抵抗力。因此,基于高地向湿地的瞬时转换的预测可能会高估未来的土地转换,从而挑战温室气体通量和沼泽产生的时间,但也意味着历史海平面上升的全部影响尚未实现。
    Ghost forests consisting of dead trees adjacent to marshes are striking indicators of climate change, and marsh migration into retreating coastal forests is a primary mechanism for marsh survival in the face of global sea-level rise. Models of coastal transgression typically assume inundation of a static topography and instantaneous conversion of forest to marsh with rising seas. In contrast, here we use four decades of satellite observations to show that many low-elevation forests along the US mid-Atlantic coast have survived despite undergoing relative sea-level rise rates (RSLRR) that are among the fastest on Earth. Lateral forest retreat rates were strongly mediated by topography and seawater salinity, but not directly explained by spatial variability in RSLRR, climate, or disturbance. The elevation of coastal tree lines shifted upslope at rates correlated with, but far less than, contemporary RSLRR. Together, these findings suggest a multi-decadal lag between RSLRR and land conversion that implies coastal ecosystem resistance. Predictions based on instantaneous conversion of uplands to wetlands may therefore overestimate future land conversion in ways that challenge the timing of greenhouse gas fluxes and marsh creation, but also imply that the full effects of historical sea-level rise have yet to be realized.
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  • 文章类型: Journal Article
    背景:一些研究发现高温与精神分裂症的恶化有关,即精神病。随着北方国家气候变化的加快,我们需要加深对体温与精神病患者入院(HA)之间关系的理解.
    目的:1)在诊断为精神分裂症的成年人中,测量夏季精神病的平均温度和HAs之间的关系。2)确定个体和生态特征对这种关系的影响。
    方法:使用魁北克的综合慢性病监测系统(QICDSS)收集了一组被诊断为精神分裂症的成年人(n=30,649)。随访时间为2001年至2019年的夏季,使用来自QICDSS的医院数据和来自美国国家航空航天局(NASA)Daymet数据库的气象数据。在魁北克省的四个地理区域,使用分布滞后非线性模型(DLNM),对精神病的平均温度(滞后达6天)与HAs之间的关系进行病例交叉分析.分析调整相对湿度,根据个人分层(年龄,性别,和合并症)和生态(物质和社会剥夺指数以及绿色空间暴露)因素,然后通过元回归进行汇总。
    结果:统计分析显示,在平均温度升高后三天(滞后3),相对于最低发病温度(MMT)的第90百分位数(OR1.040;95%CI1.008-1.074),而6天内的累积效应无统计学意义(OR1.052;95%IC0.993-1.114).分层分析显示,相对于增加的物质剥夺和减少的绿地水平,增加的HAs梯度无统计学意义。
    结论:在本项目中进行的统计分析显示了炎热天气后精神病患者的入院模式。这一发现可能有助于在快速变化的气候中更好地规划卫生服务。
    BACKGROUND: Some studies have found hot temperatures to be associated with exacerbations of schizophrenia, namely psychoses. As climate changes faster in Northern countries, our understanding of the association between temperature and hospital admissions (HA) for psychosis needs to be deepened.
    OBJECTIVE: 1) Among adults diagnosed with schizophrenia, measure the relationship between mean temperatures and HAs for psychosis during summer. 2) Determine the influence of individual and ecological characteristics on this relationship.
    METHODS: A cohort of adults diagnosed with schizophrenia (n = 30,649) was assembled using Quebec\'s Integrated Chronic Disease Surveillance System (QICDSS). The follow-up spanned summers from 2001 to 2019, using hospital data from the QICDSS and meteorological data from the National Aeronautics and Space Administration\'s (NASA) Daymet database. In four geographic regions of the province of Quebec, a conditional logistic regression was used for the case-crossover analysis of the relationship between mean temperatures (at lags up to 6 days) and HAs for psychosis using a distributed lag non-linear model (DLNM). The analyses were adjusted for relative humidity, stratified according to individual (age, sex, and comorbidities) and ecological (material and social deprivation index and exposure to green space) factors, and then pooled through a meta-regression.
    RESULTS: The statistical analyses revealed a statistically significant increase in HAs three days (lag 3) after elevated mean temperatures corresponding to the 90th percentile relative to a minimum morbidity temperature (MMT) (OR 1.040; 95% CI 1.008-1.074), while the cumulative effect over six days was not statistically significant (OR 1.052; 95% IC 0.993-1.114). Stratified analyses revealed non statistically significant gradients of increasing HAs relative to increasing material deprivation and decreasing green space levels.
    CONCLUSIONS: The statistical analyses conducted in this project showed the pattern of admissions for psychosis after hot days. This finding could be useful to better plan health services in a rapidly changing climate.
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  • 文章类型: Journal Article
    干眼症(DED)是一种常见的以干眼为主要症状的多因素引起的眼表泪液分泌紊乱,但是到目前为止,针对乌鲁木齐当地气象因素与眼表疾病之间关系的研究非常有限。此外,长期和极端气象因素对DED的影响和滞后效应尚未得到充分评价。新疆医科大学第一附属医院眼科9970例DED门诊患者的电子病例信息(乌鲁木齐,新疆,中国)在2013年1月1日至2020年12月31日之间进行了筛选和分析。我们使用时间序列分析设计和拟泊松广义线性回归模型结合分布式滞后非线性模型(DLNM)来拟合暴露于不同气象因素和极端天气对DED门诊就诊的影响。进一步进行性别亚组分析,年龄,和季节。结果表明,暴露于极低的平均温度(P1:RR=1.18),大气压力(P1:RR=1.11),相对湿度极高(P99:RR=1.35)是危险因素,而极高的大气压(P90:RR=0.883)和极低的湿度(P10:RR=0.856)似乎对降低DED的风险具有积极作用。相对湿度表现出1天的滞后效应(RR=1.06)。平均温度升高对女性DED患者(RR=0.761)有积极影响,在寒冷季节也有类似的影响(RR=0.926)。然而,相对湿度升高对女性患者有负面影响(RR=1.14).我们在这个世界上距离海洋最远的大城市和中国西北地区进行了首次大样本量时间序列分析研究,确认DED门诊量与乌鲁木齐除风速外其余三个气象因素的关联,仍然需要进行更大样本量、持续时间更长的多中心流行病学研究。
    Dry eye disease (DED) is a common disorder of tear secretion on the ocular surface caused by multiple factors with dry eyes as the main symptom, but until now studies focusing on relationship between local meteorological factors and ocular surface diseases in Urumqi are very limited. Besides, the effects of long-term and extreme meteorological factors on DED and the lag effect have not been fully evaluated. Electronic case information of 9970 DED outpatients from the Ophthalmology Department of the First Affiliated Hospital of Xinjiang Medical University (Urumqi, Xinjiang, China) between January 1, 2013, and December 31, 2020, was screened and analyzed. We used a time-series analysis design and a quasi-Poisson generalized linear regression model combined with a distributed lagged nonlinear model (DLNM) to fit the effects of exposure to different meteorological factors and extreme weather on DED outpatient visits. Subgroup analyses were further performed for gender, age, and season. The results showed that exposure to extremely low mean temperature (P1:RR = 1.18), atmospheric pressure (P1:RR = 1.11), and extremely high relative humidity (P99:RR = 1.35) were the risk factors, while extremely high atmospheric pressure (P90:RR = 0.883) and extremely low humidity (P10:RR = 0.856) appeared to have a positive effect on reduced risk of DED. Relative humidity exhibited a 1-day lag effect (RR = 1.06). Increased mean temperature positively affected female DED patients (RR = 0.761) with similar effects in the cold season (RR = 0.926). However, elevated relative humidity had a negative effect on female patients (RR = 1.14). We conducted the first large sample size time-series analysis study in this major city at the farthest distance from the ocean in the world and in northwest China, confirming the association of DED outpatient visits with the remaining three meteorological factors except wind speed in Urumqi, and a larger sample size multi-center epidemiological study with a longer duration is still needed.
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  • 文章类型: Journal Article
    广西脆弱岩溶地区是政府植被保护与恢复工作的重点地区。研究气象灾害对植被变化的影响对岩溶地区防灾减灾和生态保护具有重要意义。归一化植被指数(NDVI)作为监测植被生长的工具,对植被有很强的响应性,可以定性和定量地评价植被覆盖度及其生长活力。因此,在这项研究中,分析了植被变化趋势和多种气象灾害的影响,比如干旱,暴雨,高温,低温,利用线性趋势法对广西喀斯特地区的植被,GIS空间分析,和相关分析,利用MODISNDVI和广西岩溶地区2000-2020年的温度和降水信息。结果表明:(1)喀斯特地区NDVI显著增加,32.2%的地区植被明显改善。改善最明显的主要是在研究区的中部,东北和西南部分分散地区植被退化趋势明显。(2)在年际尺度上,NDVI与部分气象灾害指数呈负相关,如相对湿度指数,干旱天数,特大暴雨的数量,大量的暴雨,高温≥35°C的天数,高温35-37°C的天数,高温≥37°C的天数,最低温度,有效积温≤0℃。干旱对植被的明显负效应区主要集中在研究区中部,降雨主要分布在西南部,东北和西北;高温主要分布在西北和东北,低温主要集中在西南和北部。(3)在多年月度规模上,NDVI对干旱的响应,高温和低温灾害指标具有滞后效应,但对降雨灾害指数没有滞后效应。植被对干旱的滞后时间为1个月,高温和低温的滞后时间为3个月。
    Fragile karst areas of Guangxi are the key areas of vegetation protection and restoration work of the government. It is of great significance to study the effects of meteorological disasters on vegetation change for disaster prevention and reduction and ecological protection in the karst areas. The Normalized Differential Vegetation Index (NDVI), as a tool for monitoring vegetation growth, has a strong responsiveness to vegetation and can qualitatively and quantitatively evaluate the vegetation cover and its growth vitality. Therefore, in this study, we analyzed the trend of vegetation change and the impacts of multiple meteorological hazards, such as drought, torrential rainfall, high temperature, and low temperature, on the vegetation of the karst region in Guangxi by using the linear trend method, GIS spatial analysis, and correlation analysis, using the MODIS NDVI and temperature and precipitation information from 2000 to 2020 in the karst region of Guangxi. The results show that: (1) NDVI increased significantly in the karst areas, and 32.2% of the areas had significant improvement in vegetation. The improvement was the most obvious mainly in the central part of the study area, while the vegetation degradation trend was obvious in partial scattered areas in northeast and southwest. (2) On the interannual scale, NDVI was negatively correlated with some meteorological disaster indexes, such as relative humidity index, the number of drought days, the amount of extremely heavy rainstorm, the amount of heavy rainstorm, the number of days with high temperature of ≥35 °C, the number of days with high temperature of 35-37 °C, the number of days with high temperature of ≥37 °C, the minimum temperature, and the effective accumulated temperature of ≤0 °C. The obvious negative effect area of drought on vegetation was mainly concentrated in the middle of the study area, and that of rainfall was mainly distributed in the southwest, northeast and northwest; that of high temperature was mainly distributed in the northwest and northeast, and that of low temperature was mainly concentrated in the southwest and north. (3) On the multi-year monthly scale, the responses of NDVI to drought, high temperature and low temperature disaster indexes had a lag effect, but had no lag effect on rainfall disaster indexes. The lag time of vegetation to drought was 1 month, and the lag time to high temperature and low temperature was 3 months.
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  • 文章类型: Journal Article
    COVID-19肆虐巴西,其传播表现出空间异质性。环境的变化被认为是参与COVID-19传播的潜在因素。然而,大量的研究工作尚未从传染病动力学的角度阐明环境因素对COVID-19传播的风险。这项研究的目的是建立环境对COVID-19传播的影响模型,并分析在巴西流行的早期阶段,影响10个州病毒传播概率的社会生态因素如何急剧变化。首先,这项研究使用Pearson相关性分析了COVID-19发病率与社会生态因素之间的相互关系,并确定了具有显着相关性的因素是影响COVID-19传播的主要因素。然后,通过构建分布滞后非线性模型和标准两阶段元分析模型,研究了主导因素对COVID-19发病率的时滞效应,并在改进的SEIR模型中考虑了结果。最后,引入机器学习方法来探索环境传播概率与社会生态因子之间的非线性关系。通过分析环境因素对病毒传播的影响,可以发现,人类活动直接引起的人口流动对病毒传播的影响比温度和湿度更大。气象因素的异质性可以解释为巴西不同的气候模式。采用改进的SEIR模型探索COVID-19传输与环境的互联,这揭示了一种新的策略来探索它们之间的因果关系。
    COVID-19 has ravaged Brazil, and its spread showed spatial heterogeneity. Changes in the environment have been implicated as potential factors involved in COVID-19 transmission. However, considerable research efforts have not elucidated the risk of environmental factors on COVID-19 transmission from the perspective of infectious disease dynamics. The aim of this study is to model the influence of the environment on COVID-19 transmission and to analyze how the socio-ecological factors affecting the probability of virus transmission in 10 states dramatically shifted during the early stages of the epidemic in Brazil. First, this study used a Pearson correlation to analyze the interconnection between COVID-19 morbidity and socio-ecological factors and identified factors with significant correlations as the dominant factors affecting COVID-19 transmission. Then, the time-lag effect of dominant factors on the morbidity of COVID-19 was investigated by constructing a distributed lag nonlinear model and standard two-stage meta-analytic model, and the results were considered in the improved SEIR model. Lastly, a machine learning method was introduced to explore the nonlinear relationship between the environmental propagation probability and socio-ecological factors. By analyzing the impact of environmental factors on virus transmission, it can be found that population mobility directly caused by human activities had a greater impact on virus transmission than temperature and humidity. The heterogeneity of meteorological factors can be accounted for by the diverse climate patterns in Brazil. The improved SEIR model was adopted to explore the interconnection of COVID-19 transmission and the environment, which revealed a new strategy to probe the causal links between them.
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  • 文章类型: Journal Article
    在干旱或半干旱的环境中,降水对植被生长起着至关重要的作用。最近的研究表明,植被生长对降水的响应具有滞后效应。为了探索滞后现象背后的机制,我们提出并研究了具有时空非局部效应的水植被模型。结果表明,时间核函数不影响图灵分叉。为了更好地理解滞后效应和非本地竞争对植被格局形成的影响,我们选择了一些特殊的核函数,并获得了一些有见地的结果:(i)时间延迟不会触发植被格局的形成,但是可以推迟植被的进化。此外,在没有扩散的情况下,时间延迟会导致稳定性开关的发生,而在扩散的存在下,可能会出现空间非均匀时间周期解,但没有稳定性开关;(Ii)空间非局部相互作用可能触发水和植被小扩散率的模式开始,并且可以改变孤立植被斑块的数量和大小,以获得较大的扩散率。(iii)时间延迟和空间非局部竞争之间的相互作用可能会导致行波模式的出现,所以植被在太空中保持周期性,而是在时间上振荡。这些结果表明,降水可以显着影响植被的生长和空间分布。
    In an arid or semi-arid environment, precipitation plays a vital role in vegetation growth. Recent researches reveal that the response of vegetation growth to precipitation has a lag effect. To explore the mechanism behind the lag phenomenon, we propose and investigate a water-vegetation model with spatiotemporal nonlocal effects. It is shown that the temporal kernel function does not affect Turing bifurcation. For better understanding the influences of lag effect and nonlocal competition on the vegetation pattern formation, we choose some special kernel functions and obtain some insightful results: (i) Time delay does not trigger the vegetation pattern formation, but can postpone the evolution of vegetation. In addition, in the absence of diffusion, time delay can induce the occurrence of stability switches, while in the presence of diffusion, spatially nonhomogeneous time-periodic solutions may emerge, but there are no stability switches; (ii) The spatial nonlocal interaction may trigger the pattern onset for small diffusion ratio of water and vegetation, and can change the number and size of isolated vegetation patches for large diffusion ratio. (iii) The interaction between time delay and spatial nonlocal competition may induce the emergence of traveling wave patterns, so that the vegetation remains periodic in space, but is oscillating in time. These results demonstrate that precipitation can significantly affect the growth and spatial distribution of vegetation.
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  • 文章类型: Journal Article
    越来越多的证据表明,产前暴露于空气污染后早产(PTB)的风险尚无定论。这项研究的目的是调查分娩前几天的空气污染暴露与PTB之间的关系,并评估短期产前暴露于空气污染对PTB的阈值效应。这项研究收集了包括气象因素在内的数据,空气污染物,2015-2020年重庆市9区出生证明系统信息,中国。采用分布滞后非线性模型的广义加性模型(GAMs)来评估空气污染物对PTB日计数的急性影响。在控制了潜在的混杂因素后。我们观察到PM2.5在滞后0-3天和滞后10-21天与PTB的发生增加有关,第一天最强(RR=1.017,95CI:1.000-1.034),然后下降。滞后1-7天和1-30天的PM2.5阈值分别为100μg/m3和50μg/m3。PM10对PTB的滞后效应与PM2.5非常相似。此外,SO2和NO2的滞后和累积暴露也与PTB风险增加相关.CO暴露的滞后相对风险和累积相对风险最强,最大RR在滞后0时(RR=1.044,95CI:1.018,1.069)。重要的是,CO的暴露-反应曲线显示,当浓度超过1000μg/m3时,RR迅速增加。这项研究表明空气污染与PTB之间存在显着关联。相对风险随着日滞后而降低,而累积效应增加。因此,孕妇应了解空气污染的风险,并尽量避免高浓度暴露。
    Accumulating evidence suggested that the risk of preterm births (PTBs) following prenatal exposure to air pollution was inconclusive. The aim of this study is to investigate the relationship between air pollution exposure in the days before delivery and PTB and assess the threshold effect of short-term prenatal exposure to air pollution on PTB. This study collected data including meteorological factors, air pollutants, and information in Birth Certificate System from 9 districts during 2015-2020 in Chongqing, China. Generalized additive models (GAMs) with the distributed lag non-linear models were conducted to assess the acute impact of air pollutants on the daily counts of PTB, after controlling for potential confounding factors. We observed that PM2.5 was related to increased occurrence of PTB on lag 0-3 and lag 10-21 days, with the strongest on the first day (RR = 1.017, 95%CI: 1.000-1.034) and then decreasing. The thresholds of PM2.5 for lag 1-7 and 1-30 days were 100 μg/m3 and 50 μg/m3, respectively. The lag effect of PM10 on PTB was very similar to that of PM2.5. In addition, the lagged and cumulative exposure of SO2 and NO2 was also associated with the increased risk of PTB. The lag relative risk and cumulative relative risk of CO exposure were the strongest, with a maximum RR at lag 0 (RR = 1.044, 95%CI: 1.018, 1.069). Importantly, the exposure-response curve of CO showed that RR increased rapidly when the concentration exceeded 1000 μg/m3. This study indicated significant associations between air pollution and PTB. The relative risk decreases with day lag, while the cumulative effect increases. Thus, pregnant women should understand the risk of air pollution and try to avoid high concentration exposure.
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