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2.
J Nutr Health Aging ; 27(10): 861-867, 2023.
Article in English | MEDLINE | ID: mdl-37960909

ABSTRACT

OBJECTIVES: To elucidate the relationship between various sleep-wake-related indicators and nutritional status. DESIGN: Cross-sectional study. SETTING: Community-based survey between 2017 and 2022 in Yilan City, Taiwan. PARTICIPANTS: 1,905 community-dwelling older adults aged ≥65 years. MEASUREMENTS: Nutritional status was evaluated using the Mini Nutritional Assessment, and participants were classified into normal nutritional status and undernutrition groups. Regarding sleep-wake-related indicators, specific items or component scores of the Pittsburgh Sleep Quality Index were used to assess sleep-wake schedule, subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, presence of sleep disturbances, hypnotic use, and dysfunction in maintaining enthusiasm. The 5-item Athens Insomnia Scale and the Epworth Sleepiness Scale were used to evaluate insomnia and excessive daytime sleepiness, respectively. RESULTS: Of the 1,905 participants, the mean age was 75.6±7.1, with 52.2% being ≥75 years old, 58.9% were women, and 11.4% had undernutrition. After controlling for covariates, short sleepers were less likely to have undernutrition (OR: 0.63; 95% CI: 0.41-0.97); in contrast, long sleepers were more likely to exhibit undernutrition (OR: 1.52; 95% CI: 1.06-2.17). In addition, poor habitual sleep efficiency (OR:1.69; 95% CI:1.15-2.50), taking hypnotics in the past month (OR: 1.58; 95% CI: 1.12-2.24), and dysfunction in maintaining enthusiasm (OR: 1.93; 95% CI: 1.24-2.99) were associated with increased risk of undernutrition. CONCLUSIONS: Among older adults, various sleep-wake-related indicators differed in their relationships with nutritional status. Specific sleep-wake disturbances may indicate undernutrition in this population.


Subject(s)
Malnutrition , Sleep Initiation and Maintenance Disorders , Sleep Wake Disorders , Humans , Female , Aged , Aged, 80 and over , Male , Sleep Initiation and Maintenance Disorders/epidemiology , Independent Living , Nutritional Status , Taiwan/epidemiology , Cross-Sectional Studies , Sleep , Malnutrition/complications , Malnutrition/epidemiology , Sleep Wake Disorders/epidemiology
3.
Environ Sci Technol ; 55(22): 15287-15300, 2021 11 16.
Article in English | MEDLINE | ID: mdl-34724610

ABSTRACT

Annual global satellite-based estimates of fine particulate matter (PM2.5) are widely relied upon for air-quality assessment. Here, we develop and apply a methodology for monthly estimates and uncertainties during the period 1998-2019, which combines satellite retrievals of aerosol optical depth, chemical transport modeling, and ground-based measurements to allow for the characterization of seasonal and episodic exposure, as well as aid air-quality management. Many densely populated regions have their highest PM2.5 concentrations in winter, exceeding summertime concentrations by factors of 1.5-3.0 over Eastern Europe, Western Europe, South Asia, and East Asia. In South Asia, in January, regional population-weighted monthly mean PM2.5 concentrations exceed 90 µg/m3, with local concentrations of approximately 200 µg/m3 for parts of the Indo-Gangetic Plain. In East Asia, monthly mean PM2.5 concentrations have decreased over the period 2010-2019 by 1.6-2.6 µg/m3/year, with decreases beginning 2-3 years earlier in summer than in winter. We find evidence that global-monitored locations tend to be in cleaner regions than global mean PM2.5 exposure, with large measurement gaps in the Global South. Uncertainty estimates exhibit regional consistency with observed differences between ground-based and satellite-derived PM2.5. The evaluation of uncertainty for agglomerated values indicates that hybrid PM2.5 estimates provide precise regional-scale representation, with residual uncertainty inversely proportional to the sample size.


Subject(s)
Air Pollutants , Air Pollution , Aerosols/analysis , Air Pollutants/analysis , Air Pollution/analysis , Environmental Monitoring , Particulate Matter/analysis , Uncertainty
4.
Sci Adv ; 7(26)2021 Jun.
Article in English | MEDLINE | ID: mdl-34162552

ABSTRACT

Lockdowns during the COVID-19 pandemic provide an unprecedented opportunity to examine the effects of human activity on air quality. The effects on fine particulate matter (PM2.5) are of particular interest, as PM2.5 is the leading environmental risk factor for mortality globally. We map global PM2.5 concentrations for January to April 2020 with a focus on China, Europe, and North America using a combination of satellite data, simulation, and ground-based observations. We examine PM2.5 concentrations during lockdown periods in 2020 compared to the same periods in 2018 to 2019. We find changes in population-weighted mean PM2.5 concentrations during the lockdowns of -11 to -15 µg/m3 across China, +1 to -2 µg/m3 across Europe, and 0 to -2 µg/m3 across North America. We explain these changes through a combination of meteorology and emission reductions, mostly due to transportation. This work demonstrates regional differences in the sensitivity of PM2.5 to emission sources.

5.
Environ Sci Technol ; 54(13): 7879-7890, 2020 07 07.
Article in English | MEDLINE | ID: mdl-32491847

ABSTRACT

Exposure to outdoor fine particulate matter (PM2.5) is a leading risk factor for mortality. We develop global estimates of annual PM2.5 concentrations and trends for 1998-2018 using advances in satellite observations, chemical transport modeling, and ground-based monitoring. Aerosol optical depths (AODs) from advanced satellite products including finer resolution, increased global coverage, and improved long-term stability are combined and related to surface PM2.5 concentrations using geophysical relationships between surface PM2.5 and AOD simulated by the GEOS-Chem chemical transport model with updated algorithms. The resultant annual mean geophysical PM2.5 estimates are highly consistent with globally distributed ground monitors (R2 = 0.81; slope = 0.90). Geographically weighted regression is applied to the geophysical PM2.5 estimates to predict and account for the residual bias with PM2.5 monitors, yielding even higher cross validated agreement (R2 = 0.90-0.92; slope = 0.90-0.97) with ground monitors and improved agreement compared to all earlier global estimates. The consistent long-term satellite AOD and simulation enable trend assessment over a 21 year period, identifying significant trends for eastern North America (-0.28 ± 0.03 µg/m3/yr), Europe (-0.15 ± 0.03 µg/m3/yr), India (1.13 ± 0.15 µg/m3/yr), and globally (0.04 ± 0.02 µg/m3/yr). The positive trend (2.44 ± 0.44 µg/m3/yr) for India over 2005-2013 and the negative trend (-3.37 ± 0.38 µg/m3/yr) for China over 2011-2018 are remarkable, with implications for the health of billions of people.


Subject(s)
Air Pollutants , Air Pollution , Aerosols/analysis , Air Pollutants/analysis , Air Pollution/analysis , China , Environmental Monitoring , Europe , Humans , India , Particulate Matter/analysis
6.
J Geophys Res Atmos ; 123(1): 380-400, 2018 Jan 16.
Article in English | MEDLINE | ID: mdl-30123731

ABSTRACT

The Suomi National Polar-Orbiting Partnership (S-NPP) satellite, launched in late 2011, carries the Visible Infrared Imaging Radiometer Suite (VIIRS) and several other instruments. VIIRS has similar characteristics to prior satellite sensors used for aerosol optical depth (AOD) retrieval, allowing the continuation of space-based aerosol data records. The Deep Blue algorithm has previously been applied to retrieve AOD from Sea-viewing Wide Field-of-view Sensor (SeaWiFS) and Moderate Resolution Imaging Spectro-radiometer (MODIS) measurements over land. The SeaWiFS Deep Blue data set also included a SeaWiFS Ocean Aerosol Retrieval (SOAR) algorithm to cover water surfaces. As part of NASA's VIIRS data processing, Deep Blue is being applied to VIIRS data over land, and SOAR has been adapted from SeaWiFS to VIIRS for use over water surfaces. This study describes SOAR as applied in version 1 of NASA's S-NPP VIIRS Deep Blue data product suite. Several advances have been made since the SeaWiFS application, as well as changes to make use of the broader spectral range of VIIRS. A preliminary validation against Maritime Aerosol Network (MAN) measurements suggests a typical uncertainty on retrieved 550nm AOD of order ±(0.03+10%), comparable to existing SeaWiFS/MODIS aerosol data products. Retrieved Ångström exponent and fine mode AOD fraction are also well-correlated with MAN data, with small biases and uncertainty similar to or better than SeaWiFS/MODIS products.

7.
J Geophys Res Atmos ; 123(10): 5560-5587, 2018 May 27.
Article in English | MEDLINE | ID: mdl-32661496

ABSTRACT

Analysis of sun photometer measured and satellite retrieved aerosol optical depth (AOD) data has shown that major aerosol pollution events with very high fine mode AOD (>1.0 in mid-visible) in the China/Korea/Japan region are often observed to be associated with significant cloud cover. This makes remote sensing of these events difficult even for high temporal resolution sun photometer measurements. Possible physical mechanisms for these events that have high AOD include a combination of aerosol humidification, cloud processing, and meteorological co-variation with atmospheric stability and convergence. The new development of Aerosol Robotic network (AERONET) Version 3 Level 2 AOD with improved cloud screening algorithms now allow for unprecedented ability to monitor these extreme fine mode pollution events. Further, the Spectral Deconvolution Algorithm (SDA) applied to Level 1 data (L1; no cloud screening) provides an even more comprehensive assessment of fine mode AOD than L2 in current and previous data versions. Studying the 2012 winter-summer period, comparisons of AERONET L1 SDA daily average fine mode AOD data showed that Moderate Resolution Imaging Spectroradiometer (MODIS) satellite remote sensing of AOD often did not retrieve and/or identify some of the highest fine mode AOD events in this region. Also, compared to models that include data assimilation of satellite retrieved AOD, the L1 SDA fine mode AOD was significantly higher in magnitude, particularly for the highest AOD events that were often associated with significant cloudiness.

8.
Oncogene ; 36(38): 5439, 2017 09 21.
Article in English | MEDLINE | ID: mdl-28714963

ABSTRACT

This corrects the article DOI: 10.1038/onc.2014.184.

9.
Atmos Meas Tech ; 10(4): 1425-1444, 2017.
Article in English | MEDLINE | ID: mdl-30263081

ABSTRACT

The Visible Infrared Imaging Radiometer Suite (VIIRS) is being used to continue the record of Earth Science observations and data products produced routinely from National Aeronautics and Space Administration (NASA) Moderate Resolution Imaging Spectroradiometer (MODIS) measurements. However, the absolute calibration of VIIRS's reflected solar bands is thought to be biased, leading to offsets in derived data products such as aerosol optical depth (AOD) as compared to when similar algorithms are applied to different sensors. This study presents a cross-calibration of these VIIRS bands against MODIS Aqua over dark water scenes, finding corrections to the NASA VIIRS Level 1 (version 2) reflectances between approximately +1 % and -7 % (dependent on band) are needed to bring the two into alignment (after accounting for expected differences resulting from different band spectral response functions), and indications of relative trending of up to ^0.35 % per year in some bands. The derived calibration gain corrections are also applied to the VIIRS reflectance and then used in an AOD retrieval, and are shown to decrease the bias and total error in AOD across the midvisible spectral region compared to the standard VIIRS NASA reflectance calibration. The resulting AOD bias characteristics are similar to those of NASA MODIS AOD data products, which is encouraging in terms of multisensor data continuity.

10.
J Geophys Res Atmos ; 122(19): 10384-10401, 2017 Oct 16.
Article in English | MEDLINE | ID: mdl-29963346

ABSTRACT

Aerosol Robotic Network (AERONET)-based nonspherical dust optical models are developed and applied to the Satellite Ocean Aerosol Retrieval (SOAR) algorithm as part of the Version 1 Visible Infrared Imaging Radiometer Suite (VIIRS) NASA 'Deep Blue' aerosol data product suite. The optical models are created using Version 2 AERONET inversion data at six distinct sites influenced frequently by dust aerosols from different source regions. The same spheroid shape distribution as used in the AERONET inversion algorithm is assumed to account for the nonspherical characteristics of mineral dust, which ensures the consistency between the bulk scattering properties of the developed optical models with the AERONET-retrieved microphysical and optical properties. For the Version 1 SOAR aerosol product, the dust optical models representative for Capo Verde site are used, considering the strong influence of Saharan dust over the global ocean in terms of amount and spatial coverage. Comparisons of the VIIRS-retrieved aerosol optical properties against AERONET direct-Sun observations at three island/coastal sites suggest that the use of nonspherical dust optical models significantly improves the retrievals of aerosol optical depth (AOD) and Ångström exponent by mitigating the well-known artifact of scattering angle dependence of the variables observed when incorrectly assuming spherical dust. The resulting removal of these artifacts results in a more natural spatial pattern of AOD along the transport path of Saharan dust to the Atlantic Ocean; i.e., AOD decreases with increasing distance transported, whereas the spherical assumption leads to a strong wave pattern due to the spurious scattering angle dependence of AOD.

11.
J Geophys Res Atmos ; 122(18): 9945-9967, 2017 Aug 27.
Article in English | MEDLINE | ID: mdl-30140601

ABSTRACT

The Deep Blue (DB) and Satellite Ocean Aerosol Retrieval (SOAR) algorithms have previously been applied to observations from sen-sors like the Moderate Resolution Imaging Spectroradiometers (MODIS) and Sea-viewing Wide Field-of-view Sensor (SeaWiFS) to provide records of mid-visible aerosol optical depth (AOD) and related quantities over land and ocean surfaces respectively. Recently, DB and SOAR have also been applied to Ad-vanced Very High Resolution Radiometer (AVHRR) observations from several platforms (NOAA11, NOAA14, and NOAA18), to demonstrate the potential for extending the DB and SOAR AOD records. This study provides an evaluation of the initial version (V001) of the resulting AVHRR-based AOD data set, including validation against Aerosol Robotic Network (AERONET) and ship-borne observations, and comparison against both other AVHRR AOD Research (GESTAR), Universities Space Research Association. records and MODIS/SeaWiFS products at select long-term AERONET sites. Although it is difficult to distil error characteristics into a simple expression, the results suggest that one standard deviation confidence intervals on retrieved AOD of ±(0.03+15%) over water and ±(0.05+25%) over land represent the typical level of uncertainty, with a tendency towards negative biases in high-AOD conditions, caused by a combination of algorithmic assumptions and sensor calibration issues. Most of the available validation data are for NOAA18 AVHRR, although performance appears to be similar for the NOAA11 and NOAA14 sensors as well.

12.
Environ Sci Technol ; 50(7): 3762-72, 2016 Apr 05.
Article in English | MEDLINE | ID: mdl-26953851

ABSTRACT

We estimated global fine particulate matter (PM2.5) concentrations using information from satellite-, simulation- and monitor-based sources by applying a Geographically Weighted Regression (GWR) to global geophysically based satellite-derived PM2.5 estimates. Aerosol optical depth from multiple satellite products (MISR, MODIS Dark Target, MODIS and SeaWiFS Deep Blue, and MODIS MAIAC) was combined with simulation (GEOS-Chem) based upon their relative uncertainties as determined using ground-based sun photometer (AERONET) observations for 1998-2014. The GWR predictors included simulated aerosol composition and land use information. The resultant PM2.5 estimates were highly consistent (R(2) = 0.81) with out-of-sample cross-validated PM2.5 concentrations from monitors. The global population-weighted annual average PM2.5 concentrations were 3-fold higher than the 10 µg/m(3) WHO guideline, driven by exposures in Asian and African regions. Estimates in regions with high contributions from mineral dust were associated with higher uncertainty, resulting from both sparse ground-based monitoring, and challenging conditions for retrieval and simulation. This approach demonstrates that the addition of even sparse ground-based measurements to more globally continuous PM2.5 data sources can yield valuable improvements to PM2.5 characterization on a global scale.


Subject(s)
Environmental Monitoring/methods , Models, Theoretical , Particulate Matter/analysis , Aerosols/analysis , Algorithms , Dust , Environmental Monitoring/instrumentation , Environmental Monitoring/statistics & numerical data , Geological Phenomena , Models, Statistical , Satellite Communications
13.
Aerosol Air Qual Res ; 16(11): 2831-2842, 2016 Nov.
Article in English | MEDLINE | ID: mdl-32908468

ABSTRACT

This study evaluates the height of biomass burning smoke aerosols retrieved from a combined use of Visible Infrared Imaging Radiometer Suite (VIIRS), Ozone Mapping and Profiler Suite (OMPS), and Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) observations. The retrieved heights are compared against spaceborne and ground-based lidar measurements during the peak biomass burning season (March and April) over Southeast Asia from 2013 to 2015. Based on the comparison against CALIOP, a quality assurance (QA) procedure is developed. It is found that 74% (81-84%) of the retrieved heights fall within 1 km of CALIOP observations for unfiltered (QA-filtered) data, with root-mean-square error (RMSE) of 1.1 km (0.8-1.0 km). Eliminating the requirement for CALIOP observations from the retrieval process significantly increases the temporal coverage with only a slight decrease in the retrieval accuracy; for best QA data, 64% of data fall within 1 km of CALIOP observations with RMSE of 1.1 km. When compared with Micro-Pulse Lidar Network (MPLNET) measurements deployed at Doi Ang Khang, Thailand, the retrieved heights show RMSE of 1.7 km (1.1 km) for unfiltered (QA-filtered) data for the complete algorithm, and 0.9 km (0.8 km) for the simplified algorithm.

14.
J Air Waste Manag Assoc ; 65(12): 1395-412, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26422145

ABSTRACT

UNLABELLED: This two-part paper reports on the development, implementation, and improvement of a version of the Community Multi-Scale Air Quality (CMAQ) model that assimilates real-time remotely-sensed aerosol optical depth (AOD) information and ground-based PM2.5 monitor data in routine prognostic application. The model is being used by operational air quality forecasters to help guide their daily issuance of state or local-agency-based air quality alerts (e.g. action days, health advisories). Part 1 describes the development and testing of the initial assimilation capability, which was implemented offline in partnership with NASA and the Visibility Improvement State and Tribal Association of the Southeast (VISTAS) Regional Planning Organization (RPO). In the initial effort, MODIS-derived aerosol optical depth (AOD) data are input into a variational data-assimilation scheme using both the traditional Dark Target and relatively new "Deep Blue" retrieval methods. Evaluation of the developmental offline version, reported in Part 1 here, showed sufficient promise to implement the capability within the online, prognostic operational model described in Part 2. In Part 2, the addition of real-time surface PM2.5 monitoring data to improve the assimilation and an initial evaluation of the prognostic modeling system across the continental United States (CONUS) is presented. IMPLICATIONS: Air quality forecasts are now routinely used to understand when air pollution may reach unhealthy levels. For the first time, an operational air quality forecast model that includes the assimilation of remotely-sensed aerosol optical depth and ground based PM2.5 observations is being used. The assimilation enables quantifiable improvements in model forecast skill, which improves confidence in the accuracy of the officially-issued forecasts. This helps air quality stakeholders be more effective in taking mitigating actions (reducing power consumption, ride-sharing, etc.) and avoiding exposures that could otherwise result in more serious air quality episodes or more deleterious health effects.


Subject(s)
Aerosols/chemistry , Air Pollutants/chemistry , Particulate Matter/chemistry , Environmental Monitoring
15.
Oncogene ; 34(29): 3882-3, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26179457

ABSTRACT

Correction to: Oncogene (2015) 34, 2505­2515; doi:10.1038/onc. 2014.184; published online 7 July 2014. Since the publication of the above paper, the authors found a misplacing band in Figure 2e. The correct version of the figure is given below. The correction does not affect the validity of the data presented and does not limit the conclusions drawn in the paper. The authors apologize for this mistake.

17.
Oncogene ; 34(16): 2072-82, 2015 Apr 16.
Article in English | MEDLINE | ID: mdl-24909176

ABSTRACT

The dual role of the microRNA-29 (miR-29) family in tumor progression and metastasis in solid tumors has been reported. Evidence for the role of miR-29 in tumor malignancy and its prognostic value in overall survival (OS) and relapse-free survival (RFS) in non-small cell lung cancer (NSCLC) remains conflicting. Mechanistic studies presented herein demonstrated that c-Myc suppressed the expression of miR-29b, promoting soft agar growth and invasion capability in lung cancer cells. Interestingly, the decrease in the expression of miR-29b by c-Myc is responsible for soft agar growth and invasiveness mediated by FHIT loss due to promoter methylation. Among patients, low expression of miR-29b and FHIT was more common in tumors with high c-Myc expression than in tumors with low c-Myc expression. Kaplan-Meier and Cox regression analysis showed that tumors with high c-Myc, low miR-29b and low FHIT expression had shorter OS and RFS periods than their counterparts. In conclusion, the decrease in the expression of miR-29b by c-Myc may be responsible for FHIT loss-mediated tumor aggressiveness and for poor outcome in NSCLC. Therefore, we suggest that restoration of the miR-29b expression using the c-Myc inhibitor might be helpful in suppressing tumor aggressiveness mediated by FHIT loss and consequently improving outcomes in NSCLC patients with tumors with low expression of FHIT.


Subject(s)
Acid Anhydride Hydrolases/biosynthesis , Carcinoma, Non-Small-Cell Lung/pathology , Lung Neoplasms/pathology , MicroRNAs/genetics , Neoplasm Proteins/biosynthesis , Proto-Oncogene Proteins c-myc/antagonists & inhibitors , Acid Anhydride Hydrolases/genetics , Carcinoma, Non-Small-Cell Lung/genetics , Cell Line, Tumor , Cell Movement/genetics , DNA Methylation , Disease-Free Survival , Gene Expression Regulation, Neoplastic , Humans , Lung Neoplasms/genetics , MicroRNAs/biosynthesis , Neoplasm Invasiveness , Neoplasm Proteins/genetics , Neoplasm Recurrence, Local , Promoter Regions, Genetic/genetics , Proto-Oncogene Proteins c-myc/biosynthesis , Signal Transduction/genetics
18.
Oncogene ; 34(19): 2505-15, 2015 May 07.
Article in English | MEDLINE | ID: mdl-24998847

ABSTRACT

Fragile histidine triad (FHIT) loss by the two-hit mechanism of loss of heterozygosity and promoter hypermethylation commonly occurrs in non-small cell lung cancer (NSCLC) and may confer cisplatin resistance in NSCLC cells. However, the underlying mechanisms of FHIT loss in cisplatin resistance and the response to cisplatin-based chemotherapy in NSCLC patients have not yet been reported. In the present study, inhibition concentration of 50% cell viability induced by cisplatin (IC50) and soft agar growth and invasion capability were increased and decreased in FHIT-knockdown and -overexpressing cells, respectively. Mechanistically, Slug transcription is upregulated by AKT/NF-κB activation due to FHIT loss and, in turn, Slug suppresses PUMA expression; this decrease of PUMA by FHIT loss is responsible for cisplatin resistance. In addition, cisplatin resistance due to FHIT loss can be conquered by AKT inhibitor-perifosine in xenograft tumors. Among NSCLC patients, low FHIT, high p-AKT, high Slug and low PUMA were correlated with shorter overall survival, relapse-free survival and poorer response to cisplatin-based chemotherapy. Therefore, the AKT inhibitor perifosine might potentially overcome the resistance to cisplatin-based chemotherapy in NSCLC patients with low-FHIT tumors, and consequently improve the outcome.


Subject(s)
Acid Anhydride Hydrolases/genetics , Drug Resistance, Neoplasm/genetics , Neoplasm Proteins/genetics , Proto-Oncogene Proteins c-akt/metabolism , Transcription Factor RelA/metabolism , Transcription Factors/metabolism , Adult , Aged , Aged, 80 and over , Animals , Antineoplastic Agents/therapeutic use , Apoptosis/genetics , Apoptosis Regulatory Proteins/genetics , Apoptosis Regulatory Proteins/metabolism , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/mortality , Cisplatin/therapeutic use , Female , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/mortality , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Middle Aged , Neoplasm Transplantation , Nitriles/pharmacology , Phosphorylcholine/analogs & derivatives , Phosphorylcholine/pharmacology , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , RNA Interference , RNA, Small Interfering , Snail Family Transcription Factors , Sulfones/pharmacology , Transcription Factor RelA/antagonists & inhibitors , Transcription Factors/genetics , Transplantation, Heterologous , Treatment Outcome
19.
Environ Sci Technol ; 48(19): 11109-18, 2014 Oct 07.
Article in English | MEDLINE | ID: mdl-25184953

ABSTRACT

Ambient fine particulate matter (PM2.5) is a leading environmental risk factor for premature mortality. We use aerosol optical depth (AOD) retrieved from two satellite instruments, MISR and SeaWiFS, to produce a unified 15-year global time series (1998-2012) of ground-level PM2.5 concentration at a resolution of 1° x 1°. The GEOS-Chem chemical transport model (CTM) is used to relate each individual AOD retrieval to ground-level PM2.5. Four broad areas showing significant, spatially coherent, annual trends are examined in detail: the Eastern U.S. (-0.39 ± 0.10 µg m(-3) yr(-1)), the Arabian Peninsula (0.81 ± 0.21 µg m(-3) yr(-1)), South Asia (0.93 ± 0.22 µg m(-3) yr(-1)) and East Asia (0.79 ± 0.27 µg m(-3) yr(-1)). Over the period of dense in situ observation (1999-2012), the linear tendency for the Eastern U.S. (-0.37 ± 0.13 µg m(-3) yr(-1)) agrees well with that from in situ measurements (-0.38 ± 0.06 µg m(-3) yr(-1)). A GEOS-Chem simulation reveals that secondary inorganic aerosols largely explain the observed PM2.5 trend over the Eastern U.S., South Asia, and East Asia, while mineral dust largely explains the observed trend over the Arabian Peninsula.


Subject(s)
Aerosols/analysis , Particulate Matter/analysis , Asia , Dust , Environmental Monitoring , Asia, Eastern , Models, Chemical , Satellite Imagery , United States
20.
Environ Pollut ; 195: 292-307, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25085565

ABSTRACT

The interactions between aerosols, clouds, and precipitation remain among the largest sources of uncertainty in the Earth's energy budget. Biomass-burning aerosols are a key feature of the global aerosol system, with significant annually-repeating fires in several parts of the world, including Southeast Asia (SEA). SEA in particular provides a "natural laboratory" for these studies, as smoke travels from source regions downwind in which it is coupled to persistent stratocumulus decks. However, SEA has been under-exploited for these studies. This review summarizes previous related field campaigns in SEA, with a focus on the ongoing Seven South East Asian Studies (7-SEAS) and results from the most recent BASELInE deployment. Progress from remote sensing and modeling studies, along with the challenges faced for these studies, are also discussed. We suggest that improvements to our knowledge of these aerosol/cloud effects require the synergistic use of field measurements with remote sensing and modeling tools.


Subject(s)
Aerosols/analysis , Air Pollutants/analysis , Atmosphere/chemistry , Fires/statistics & numerical data , Smoke/analysis , Asia, Southeastern , Biomass , Climate
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