Dengue fever is one of the most widespread vector-borne diseases and has caused more than 50million infections annually over the world. For the purposes of disease prevention and climate change ...health impact assessment, it is crucial to understand the weather-disease associations for dengue fever. This study investigated the nonlinear delayed impact of meteorological conditions on the spatiotemporal variations of dengue fever in southern Taiwan during 1998–2011. We present a novel integration of a distributed lag nonlinear model and Markov random fields to assess the nonlinear lagged effects of weather variables on temporal dynamics of dengue fever and to account for the geographical heterogeneity. This study identified the most significant meteorological measures to dengue fever variations, i.e., weekly minimum temperature, and the weekly maximum 24-hour rainfall, by obtaining the relative risk (RR) with respect to disease counts and a continuous 20-week lagged time. Results show that RR increased as minimum temperature increased, especially for the lagged period 5–18weeks, and also suggest that the time to high disease risks can be decreased. Once the occurrence of maximum 24-hour rainfall is >50mm, an associated increased RR lasted for up to 15weeks. A temporary one-month decrease in the RR of dengue fever is noted following the extreme rain. In addition, the elevated incidence risk is identified in highly populated areas. Our results highlight the high nonlinearity of temporal lagged effects and magnitudes of temperature and rainfall on dengue fever epidemics. The results can be a practical reference for the early warning of dengue fever.
•Meteorological effects to dengue fever risks are nonlinear in magnitude and lagged.•Minimum temperature > 20ºC and maximum 24-h rainfall > 50 mm increased relative risk.•Time lags were reduced as minimum temperature and maximum 24-h rainfall increased.•Spatial variation is significant in dengue fever incidence.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The rapid growth of Internet of Things has provided a new aspect to air quality monitoring system. In Taiwan, over 5000 PM2.5 sensors have been installed in the last two years. The greatest asset of ...low-cost sensors is possibly mapping spatiotemporal air pollution with finer resolution. But the data quality of low-cost sensors is the most common question that how to take proper interpretation of the measurements. This study proposes an efficient calibration approach based on generalized additive model which is further applied to a particular low-cost PM2.5 sensor in Taiwan. The study carried out a field calibration that collecting both measurements of low-cost sensors and the regulatory stations, and investigated the space/time bias between the low-cost sensors and regulatory stations. Results show that the proposed approach can explain the variability of the biases from the low-cost sensors with R-square of 0.76. In addition, the present calibration model can quantify the uncertainty of the low-cost sensors observations and the average standard deviation is about 13.85% with respect to its adjusted levels. This operational spatiotemporal data calibration approach provides an useful information for local communities and governmental agency to face the new era of IoT sensor for air quality monitoring.
•An effective operational low-cost PM2.5 sensors data calibration approach is proposed.•The nonlinear bias relationship between the low-cost and regulatory sensors is identified.•PM2.5 levels and temperature in low-cost sensors can be used for bias correction.•Data calibration is essential to mitigate the misleading of risk perception from low-cost sensors.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
•Major space–time groundwater processes in Pingtung are obtained by EOF method.•Rainfall–groundwater associations among the groundwater patterns are different.•Heavy rainfall events induced small, ...prompt and nonstationary recharges.•Stationary and strong seasonal recharges rainfall events are shown close to mountaineous areas.•Time lags between rainfall and groundwater recharges can vary in 3–75days.
Rainfall–groundwater interactions are complex and can depend upon a variety of hydro-geological and geographical conditions and can commonly present high nonlinearity. This study proposed an integration of cross wavelet transform and empirical orthogonal function (EOF) analysis to analyze the space–time nonlinear relationships between the precipitation and groundwater changes. The proposed method was applied to investigating the non-stationary and nonlinear precipitation–groundwater relationships in Pingtung Plain aquifer during 2005–2010. We analyzed daily groundwater and rainfall observations at 47 wells and 27 stations across the study area operated by Taiwan Water Resources Agency and Central Weather Bureau respectively. Results show that EOF method revealed three major space–time patterns of the groundwater levels. The cross wavelet transform further identified the lagged effects between precipitation and groundwater changes. The temporal lags can vary not only with respect to the temporal scales of groundwater processes, but also the different identified groundwater regions, which can associate with distinct physical mechanisms. In general, the lagged periods between high frequency signals of precipitation and groundwater can range from 0 to 18days, showing how rainfall events perturbed the groundwater levels across space. The long-term lags for the three identified underlying groundwater processes were 3.71, 56.6, and 72.07days, respectively, showing seasonal recharge patterns can depend upon the geographical and geological conditions. Our results distinguished the space–time recharge processes in different frequencies, which present nonlinear and non-stationary rainfall–recharge interactions of a groundwater system, which can be spatially and frequency dependent.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Groundwater extraction from aquifers is a common practice for human use, and variations in groundwater levels can provide valuable information on the hydrogeological properties of the aquifer. ...However, reliable data on pumping rates and distribution are often lacking due to unsupervised groundwater pumping activities. This study presents a new mathematical model for transfer function modeling that depicts the drawdown response caused by pumping in an unconfined aquifer system. To account for the dense and unsupervised pumping events, the uniform pumping approach was used to estimate these effects. To more accurately represent unconfined flow, the model first integrates lagging theory into a response function derived from the Boussinesq equation. The lagging theory accounts for the effects of both inertial force and capillary suction. Furthermore, the model has been used to derive both specific yield and transmissivity along with two lagging parameters simultaneously using only groundwater level information from the Choshui River region in Taiwan. The estimated results suggest that this approach provides reliable estimates of hydrogeological parameters, demonstrating its usefulness for water resource management and water budget evaluation.
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This study examines the process of extracting water from underground sources, known as aquifers, and how monitoring changes in water levels can provide valuable insights into the characteristics of the aquifer. It can be challenging to obtain accurate information on the amount of water being pumped out due to inadequate monitoring. The researchers have developed a novel approach to comprehending the impact of water extraction on the water levels in these subterranean regions. This method considers the general pattern of water use to pump out water without close monitoring. It also incorporates realistic ideas about how water moves through the ground, taking into account factors such as the delay in water movement and the role of different forces in the soil. The study applied this method to data from Taiwan's Choshui River area and was able to determine important details about the aquifer using only water level information. These findings hold promise for effective water resource management and the wise use of water.
A novel mathematical model for groundwater extraction in unconfined aquifer systems. The model captures drawdown response due to pumping, integrates insights from uniform pumping approach for reflecting heavy pumping activities, the Boussinesq equation for formulating the unconfined flow, and lagging theory for capturing the effect from capillary fringe.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Abstract Background The aging rate in Taiwan is the second highest in the world. As the population ages quickly, the prevalence of dementia increases rapidly. There are some studies that have ...explored the association between air pollution and cognitive decline, but the association between air pollution and dementia has not been directly evaluated. Methods This was a case-control study comprising 249 Alzheimer's disease (AD) patients, 125 vascular dementia (VaD) patients, and 497 controls from three teaching hospitals in northern Taiwan from 2007 to 2010. Data of particulate matter <10 μm in diameter (PM10 ) and ozone were obtained from the Taiwan Environmental Protection Administration for 12 and 14 years, respectively. Blood samples were collected to determine the apolipoprotein E ( APOE ) ɛ4 haplotype. Bayesian maximum entropy was used to estimate the individual exposure level of air pollutants, which was then tertiled for analysis. Conditional logistic regression models were used to estimate adjusted odds ratios (AORs) and 95% confidence intervals between the association of PM10 and ozone exposure with AD and VaD risk. Results The highest tertile of PM10 (≥49.23 μg/m3 ) or ozone (≥21.56 ppb) exposure was associated with increased AD risk (highest vs. lowest tertile of PM10 : AOR = 4.17; highest vs. lowest tertile of ozone: AOR = 2.00). Similar finding was observed for VaD. The association with AD and VaD risk remained for the highest tertile PM10 exposure after stratification by APOE ɛ4 status and gender. Conclusions Long-term exposure to the highest tertile of PM10 or ozone was significantly associated with an increased risk of AD and VaD.
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FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Concerns have been raised about the adverse impact of Asian dust storms (ADS) on human health; however, few studies have examined the effect of these events on children's health. Using databases from ...the Taiwan National Health Insurance and Taiwan Environmental Protection Agency, this study investigates the documented daily visits of children to respiratory clinics during and after ADS that occurred from 1997 to 2007 among 12 districts across Taipei City by applying a Bayesian structural additive regressive model controlled for spatial and temporal patterns. This study finds that the significantly impact of elevated children's respiratory clinic visits happened after ADS. Five of the seven lagged days had increasing percentages of relative rate, which was consecutively elevated from a 2-day to a 5-day lag by 0.63%∼2.19% for preschool children (i.e., 0∼6 years of age) and 0.72%∼3.17% for school children (i.e., 7∼14 years of age). The spatial pattern of clinic visits indicated that geographical heterogeneity was possibly associated with the clinic's location and accessibility. Moreover, day-of-week effects were elevated on Monday, Friday, and Saturday. We concluded that ADS may significantly increase the risks of respiratory diseases consecutively in the week after exposure, especially in school children.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Ambient air pollution has been associated with many health conditions, but little is known about its effects on neurodegenerative diseases, such as Parkinson's disease (PD). In this study, we ...investigated the influence of ambient air pollution on PD in a nationwide population-based case–control study in Taiwan.
We identified 11,117 incident PD patients between 2007 and 2009 from the Taiwanese National Health Insurance Research Database and selected 44,468 age- and gender-matched population controls from the longitudinal health insurance database. The average ambient pollutant exposure concentrations from 1998 through the onset of PD were estimated using quantile-based Bayesian Maximum Entropy models. Basing from logistic regression models, we estimated the odds ratios (ORs) and 95% confidence intervals (CIs) of ambient pollutant exposures and PD risk.
We observed positive associations between NOx, CO exposures, and PD. In multi-pollutant models, for NOx and CO above the 75th percentile exposure compared with the lowest percentile, the ORs of PD were 1.37 (95% CI=1.23–1.52) and 1.17 (95% CI=1.07–1.27), respectively.
This study suggests that ambient air pollution exposure, especially from traffic-related pollutants such as NOx and CO, increases PD risk in the Taiwanese population.
•Traffic-related pollutants NOx and CO increase the risk of PD.•High levels of coarse particles contribute to the increased risk of PD.•Traffic-related air pollution may adversely affect the aging brain.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Fine particulate matter <2.5 μm (PM2.5) has been associated with human health issues; however, findings regarding the influence of PM2.5 on respiratory disease remain inconsistent. The short-term, ...population-based association between the respiratory clinic visits of children and PM2.5 exposure levels were investigated by considering both the spatiotemporal distributions of ambient pollution and clinic visit data. We applied a spatiotemporal structured additive regression model to examine the concentration-response (C-R) association between children's respiratory clinic visits and PM2.5 concentrations. This analysis was separately performed on three respiratory disease categories that were selected from the Taiwanese National Health Insurance database, which includes 41 districts in the Taipei area of Taiwan from 2005 to 2007. The findings reveal a non-linear C-R pattern of PM2.5, particularly in acute respiratory infections. However, a PM2.5 increase at relatively lower levels can elevate the same-day respiratory health risks of both preschool children (<6 years old) and schoolchildren (6-14 years old). In preschool children, same-day health risks rise when concentrations increase from 0.76 to 7.44 μg/m(3), and in schoolchildren, same-day health risks rise when concentrations increase from 0.76 to 7.52 μg/m(3). Changes in PM2.5 levels generally exhibited no significant association with same-day respiratory risks, except in instances where PM2.5 levels are extremely high, and these occurrences do exhibit a significant positive influence on respiratory health that is especially notable in schoolchildren. A significant high relative rate of respiratory clinic visits are concentrated in highly populated areas. We highlight the non-linearity of the respiratory health effects of PM2.5 on children to investigate this population-based association. The C-R relationship in this study can provide a highly valuable alternative for assessing the effects of ambient air pollution on human health.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
BACKGROUND: Increases in certain cause-specific hospital admissions have been reported during Asian dust storms (ADS), which primarily originate from north and northwest China during winter and ...spring. However, few studies have investigated the relationship between the ADS and clinic visits for respiratory diseases in children. OBJECTIVE: We investigated the general impact to children's health across space and time by analyzing daily clinic visits for respiratory diseases among preschool and schoolchildren registered in 12 districts of Taipei City during 1997-2007 from the National Health Insurance dataset. METHODS: We applied a structural additive regression model to estimate the association between ADS episodes and children's clinic visits for respiratory diseases, controlling for space and time variations. RESULTS: Compared with weeks before ADS events, the rate of clinic visits during weeks after ADS events increased 2.54% (95% credible interval = 2.43, 2.66) for preschool children (< 6 years of age) and 5.03% (95% credible interval = 4.87, 5.20) for schoolchildren (7-14 years of age). Spatial heterogeneity in relative rates of clinic visits was also identified. Compared with the mean level of Taipei City, higher relative rates appeared in districts with or near large hospitals and medical centers. CONCLUSION: TO our knowledge, this is the first population-based study to assess the impact of ADS on children's respiratory health. Our analysis suggests that children's respiratory health was affected by ADS events across all of Taipei, especially among schoolchildren.
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BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, OILJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
Effective water resource management requires accurate estimation of the volume of water withdrawn through anthropogenic groundwater pumping. However, insufficient pumping information makes accurate ...estimation difficult. To address this issue, this study proposes a novel method for estimating pumping volumes that does not rely on pumping information. The proposed method uses high-resolution groundwater level (GWL) data from densely monitored wells and integrates Hilbert–Huang transform and empirical orthogonal function analysis to extract pump-associated signals, which can then be used to estimate total pumping. Our method was validated by analyzing GWL data from monitoring stations on the Choshui River alluvial fan in Taiwan. The results indicate the estimated pumping amount of 1.71×109 – 2.05×109 m3/year consistent with previous estimates obtained using survey and physics-based methods ranging from 9×108 m3/year to 2.2×109 m3/year. In the areas with abundant groundwater head observations, the proposed method can efficiently estimate pumping rates with a high space–time resolution, and may serve as a useful reference for groundwater management.
•This study proposes a method utilizing groundwater data to estimate spatiotemporal pumping rate.•Multi-year high space–time resolution of pumping rate distribution estimation was efficiently derived from hourly groundwater data.•The pumping rate distribution aligns with geological and agricultural water usage patterns.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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