Ambient Air Research Articles

A-085 Comparing CO2 stability in patient samples and proficiency testing material

Abstract Background Total carbon dioxide (tCO2) measurements are important in the assessment of acid-base disorders. The collection and storage conditions of specimens are important preanalytical factors that can influence the accuracy of tCO2 measurements. Proficiency testing (PT) materials are used to assess the accuracy and reliability of a laboratory’s test performance. Unsuccessful performance on PT challenges can be an indicator of procedural issues. However, the stability of tCO2 in PT material compared to physiologic specimens is unknown and no guidance is provided to laboratories on how to handle PT samples for tCO2 measurement. This study aims to compare tCO2 stability in PT material with that of plasma samples when exposed to ambient air at room temperature. Methods Using enzymatic endpoint measurement on Vitros 4600 Chemistry System, tCO2 was measured in PT material (n = 5) and patient samples (n = 6) at baseline and after exposure to air for 15, 30, 60, 90, and 120 minutes. 500μL of each sample was aliquoted into EZ-nest tube adapters and baseline measurements were immediately analyzed. Average percent difference from baseline was calculated and >-10% bias was considered acceptable. Results The average percent difference from baseline in PT samples exceeded -10% as early as 30 minutes; whereas -3% bias was observed in patient samples at 60 minutes. Results are summarized in the table below. Conclusions The assessment of tCO2 stability ensures the reliability of laboratory measurements. Our results indicate tCO2 in PT material is not stable when exposed to air beyond 15 minutes, however tCO2 in most patient samples remained stable beyond 120 minutes. Understanding the stability limits of tCO2 in PT material allows us to devise workflows that prevent sample degradation during PT events. By establishing best practices for maintaining tCO2 integrity in PT material, laboratories can enhance the accuracy of proficiency testing results.

Bilayer Interphase for Air-Stable and Dendrite-Free Lithium Metal Anode Cycling in Carbonate Electrolytes.

The intrinsic reactivity of lithium (Li) toward ambient air, combined with insufficient cycling stability in conventional electrolytes, hinders the practical adoption of Li metal anodes in rechargeable batteries. Here, a bilayer interphase for Li metal is introduced to address both its susceptibility to corrosion in ambient air and its deterioration during cycling in carbonate electrolytes. Initially, the Li metal anode is coated with a conformal bottom layer of polysiloxane bearing methacrylate, followed by further grafting with poly(vinyl ethylene carbonate) (PVEC) to enhance anti-corrosion capability and electrochemical stability. In contrast to single-layer applications of polysiloxane or PVEC, the bilayer design offers a highly uniform coating that effectively resists humid air and prevents dendritic Li growth. Consequently, it demonstrates stable plating/stripping behavior with only a marginal increase in overpotential over 200 cycles in carbonate electrolytes, even after exposure to ambient air with 46% relative humidity. The design concept paves the way for scalable production of high-voltage, long-cycling Li metal batteries.

Design and construction of a continuous industrial scale cold plasma equipment for fresh produce industry

This study presents the design, construction, and evaluation of a novel continuous industrial-scale cold plasma system optimized for the treatment of fresh produce. The system integrates multiple plasma modules with a multipin-to-plate discharge configuration, ensuring efficient generation of reactive oxygen and nitrogen species at relatively low voltages. The cold plasma modules are combined with a conveyor mechanism, allowing for continuous, uniform exposure of irregularly shaped food items, such as tomatoes, to reactive plasma species. Notably, the system operates using ambient air, and incorporates modularity for easy scalability, making it suitable for both small-scale enterprises and large-scale industrial applications.Experimental trials on tomatoes demonstrated reductions in microbial load, with the system effectively enhancing product safety while minimizing power consumption. Moreover, the integration of cold storage further extended shelf life, although optimization of plasma treatment parameters remains necessary to preserve bioactive compounds like lycopene and ascorbic acid. This research fills a critical gap in scaling cold plasma technology for industrial use, providing a sustainable and energy-efficient solution for food disinfection. The results highlight the potential of this system to meet industry demands for safe and efficient on-farm and small-scale enterprise disinfection.

Nanoscale Chemical Imaging of Amyloid Fibrils in Water Using Total-Internal-Reflection Tip-Enhanced Raman Spectroscopy.

Total-internal-reflection tip-enhanced Raman spectroscopy (TIR-TERS) imaging of amyloid-β (Aβ1-42-L34T) fibrils is performed with nanoscale spatial resolution in water, using TERS tips fabricated by bipolar electrodeposition. Ideal experimental parameters are corroborated by both theoretical simulations and TIR-TERS measurements. TIR-TERS imaging reveals the predominant parallel β-sheet secondary structure of Aβ1-42-L34T fibrils as well as the nanoscale spatial distribution of tyrosine, histidine, and phenylalanine aromatic amino acids. Their proportion in TERS spectra can be qualitatively explained by the combined effect of their localization in the Aβ1-42-L34T fibril structure and their molecular orientation with respect to the excitation laser light polarization. Conclusions drawn from the TERS experiments in water corroborate and significantly enrich our previous study in ambient air, thus confirming that hydration has only a marginal impact on the structure of such amyloid fibrils. This first TIR-TERS study in liquid opens fascinating perspectives for future applications in biology.

Experimental and comparative analysis between nitrile rubber foam insulated and vacuum insulated fiber reinforced plastic tank used in a low temperature sensible heat storage system for building space cooling applications

AbstractThermal energy storage devices are gaining importance and momentum in the building space cooling and renewable energy applications. Retaining the stored energy for long hours through proper insulation is crucial in achieving economic benefits. In the present research, a novel composite material (FRP) is introduced for the development of cool storage tank along with two different methods of insulation (nitrile rubber foam insulation and vacuum insulation) to assess the performance of cool energy retention. The results show that the effect of vacuum insulation is lower compared with nitrile rubber foam insulation. This is due to the low specific heat capacity of the FRP material compared with air that increases the surface temperature of the tank than the ambient air during the day time in the case of vacuum insulation. Hence the study concludes that the additional layer of insulation material with high specific heat capacity than the ambient air to be added on the surface to avoid the overheating of the wall surface. The results are useful in designing the insulation for thermal storage tanks and managing the heat loss.

Green hydrogen production from thermoelectric condensation of ambient moist air

As the world transitions towards reducing carbon emissions, green hydrogen produced through solar-powered alkaline water electrolysis (AWE) presents a promising eco-friendly fuel option. In response to the challenges caused by global warming, including air moisture saturation leading to unbalanced rainfall, flooding, concern for freshwater depletion and the limited availability of water and energy sources in arid regions. The present study introduces a novel method of integrating thermoelectric water condenser (TEWC) and AWE for green hydrogen production in remote and arid regions where both the water and the conventional energy sources are scarce. Numerical simulations of the present study show that the impact of relative humidity, temperature, and air flow rate significantly affect water condensation, energy requirement, and hydrogen production. The TEWC and AWE models showed excellent agreement with the experimental data. TEWC model reveled that the highest water production rate of 1.50 kg/(m2h) is achieved at ambient air temperature of 308 K and relative humidity of 80%. Furthermore, increasing the moist air flow from 1 m/s to 2 m/s results in a 47.5% increase in water production rate. The AWE model showed that cell's performance improved with higher temperatures, lower electrode-separator gap, and overpotentials. The hydrogen evolution rate reached a maximum of 5.2 kg/(m2h) at current density of 1.4 A/cm2 and potential of 3.96 V. By optimizing the TEWC and AWE systems the integrated method proved to be an efficient way of converting moist air into green hydrogen using solar energy, making it a viable and sustainable setup in remote arid regions.

ZnSnO3 micro-polyhedrons with oxygen defects derived from rubidium incorporation for enhanced ethanol detection

Detecting ethanol in ambient air is of great significance in protection of ecological environment, human health and social economy. Herein, a strategy is adopted to substantially improve the gas sensing performance of the ZnSnO3 micro-polyhedrons through rubidium (Rb) doping. In this study, a series of ZnSnO3 micro-polyhedrons with different amounts of Rb doping were successfully synthesized through a typical hydrothermal procedure and air sintering. The sensor based on 2 mol% Rb-doped ZnSnO3 exhibits high response value (108) and rapid response/recover speed (20/8 s) to 100 ppm ethanol at 260 °C, as well as outstanding repeatability and stability. Combining theoretical calculations and various characterization techniques, the improved sensing property of the 2 mol% Rb-doped ZnSnO3 to ethanol gas can be ascribed to the large specific surface area and the abundant surface defects induced by Rb incorporation. We believe that this study opens up a new perspective for developing efficient and high-performance ethanol gas sensor.

Surface Structure Formation in Plasma Cutting of Aluminum and Titanium Alloys Using Direct Current Straight and Reverse Polarity

Abstract The structural features and phase composition are examined in near-surface layers of specimens of Al-Mg, Al-Cu-Mg alloys and commercially pure titanium obtained by plasma cutting using direct current straight polarity (DCSP) and direct current reverse polarity (DCRP). It is found that the flows of molten metal ejected by the gas stream from the cut cavity during cutting form the fusion and heat-affected zones, whose structural morphology, phase composition, and thickness depend on both the selected material and the cutting mode. The fusion zone is thicker in specimens cut using DCRP than in those cut with DCSP. The thickness of the adjacent heat-affected zone is also the largest in the mode that provides a thicker fused layer. Aluminum alloy specimens cut in ambient air are characterized by the presence of oxygen in the near-surface layers. The lowest degree of oxidation is observed in Al-Mg alloy. Oxygen penetrates into the fused layer to a depth of 350–500 μm in Al-Cu-Mg and up to 200–250 μm in Al-Mg alloy. In titanium alloy, the thickness of oxide layers does not exceed 100–150 μm during straight polarity cutting and 200–250 μm during reverse polarity cutting. A thin brittle layer of TiO and TiO2 oxides is formed on the titanium alloy surface. It is shown that the generation of “water mist” around the plasma jet when cutting materials of all types with DCRP leads to a more intensive oxidation of metal, less thermal effect on the material, and reduced roughness of the cut face.

Bottom Contact Engineering for Ambient Fabrication of >25% Durable Perovskite Solar Cells.

The bottom contact in perovskite solar cells (PSCs) is easy to cause deep trap states and severe instability issues, especially under maximum power point tracking (MPPT). In this study, sodium gluconate (SG) is employed to disperse tin oxide (SnO2) nanoparticles (NPs) and regulate the interface contact at the buried interface. The SG-SnO2 electron transfer layer (ETL) enabled the deposition of pinhole-free perovskite films in ambient air and improved interface contact by bridging effect. SG-SnO2 PSCs achieved an impressive power conversion efficiency (PCE) of 25.34% (certified as 25.17%) with a high open-circuit voltage (VOC) exceeding 1.19V. The VOC loss is less than 0.34V relative to the 1.53eV bandgap, and the fill factor (FF) loss is only 2.02% due to the improved contact. The SG-SnO2 PSCs retained around 90% of their initial PCEs after 1000h operation (T90 = 1000h), higher than T80 = 1000h for the control SnO2 PSC. Microstructure analysis revealed that light-induced degradation primarily occurred at the buried holes and grain boundaries and highlighted the importance of bottom-contact engineering.

Low-temperature crosslinked hole transport material for high-performance inverted perovskite solar cells

Hole transport materials (HTMs) play a crucial role in the development of high-performance inverted perovskite solar cells (PSCs) by facilitating hole transport, passivating defects, and tuning crystallization. Achieving high efficiency and stability remains a key challenge for the PSCs. Crosslinked HTMs combine the efficiency of small molecules with enhanced environmental stability, however, a significant challenge in developing crosslinked HTMs for PSCs is the high temperature required for crosslinking. In this work, we synthesized a concise crosslinkable HTM, Tetrastyrenebiphenyldiamine (TPDA), based on a biphenyl core with four styrene groups, using a one-step method. TPDA can be crosslinked through an annealing process at 100℃ for 10 min without the need for any dopants or initiators. Interestingly, the compact films formed in the anneal process and the excellent spreadability for the perovskite precursor solution leading to the high-quality perovskite films, as a result, the inverted devices based on CL-TPDA achieve a champion power conversion efficiency (PCE) of 21.4%. Furthermore, the stability of the devices without encapsulation has notably improved. The PCE maintains over 85% of its initial value after 1000 h of storage in ambient air (25℃, relative humidity about 50%).

Evidence-driven indoor air quality improvement: An innovative and interdisciplinary approach to improving indoor air quality.

Indoor air pollution is a recognized emerging threat, claiming millions of lives annually. People are constantly exposed to ambient and indoor air pollution. The latest research shows that people in developed countries spend up to 90% of their time indoors and almost 70% at home. Although impaired IAQ represents a significant health risk, it affects people differently, and specific populations are more vulnerable: children, the elderly, and people with respiratory illnesses are more sensitive to these environmental risks. Despite rather extensive research on IAQ, most of the current understanding about the subject, which includes pollution sources, indoor-outdoor relationships, and ventilation/filtration, is still quite limited, mainly because air quality monitoring in the EU is primarily focused on ambient air quality and regulatory requirements are lacking for indoor environments. Therefore, the EDIAQI project aims to improve guidelines and awareness for advancing the IAQ in Europe and beyond by allowing user-friendly access to information about indoor air pollution exposures, sources, and related risk factors. The solution proposed with EDIAQI consists of conducting a characterization of sources and routes of exposure and dispersion of chemical, biological, and emerging indoor air pollution in multiple cities in the EU. The project will deploy cost-effective/user-friendly monitoring solutions to create new knowledge on sources, exposure routes, and indoor multipollutant body burdens. The EDIAQI project brings together 18 organizations from 11 different European countries that provide interdisciplinary skills and expertise in various fields, including environmental science and technology, medicine, and toxicology, as well as policy design and public engagement.

Boosting catalytic activity of π-π interactions-stabilized PdNPs for water-mediated Suzuki couplings of aryl chlorides

Utilizing unique interactions to enhance the catalytic performance of supported metal catalysts is a crucial strategy in catalyst design, albeit one that presents a significant challenge. This study introduces an original approach involving the use of π-π interactions to stabilize palladium nanoparticles (PdNPs) with a 2Br-substituted imidazolium-based covalent organic framework (COF, IHP-Br-PdNPs) for efficient water-mediated Suzuki reactions involving deactivated aryl chlorides and arylboronic acids at ambient conditions. Through extensive structural characterization employing techniques including Fourier transform infrared spectroscopy (FT-IR), cross-polarization magic angle spinning carbon-13 nuclear magnetic resonance (CP/MAS 13C NMR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), N2 adsorption, and X-ray photoelectron spectroscopy (XPS), we demonstrate the immobilization of highly stable and well-dispersed PdNPs was obtained. The designed IHP-Br-PdNPs demonstrate stability for up to 36 months in ambient air and can be efficiently recycled. After 9 catalytic cycles, there was no significant decline in catalytic performance, and the particle size of PdNPs remained constant at approximately 4-8 nm throughout the reactions. The coordination mode between the stabilizer and metal, specifically the π-π interaction between the 2Br-substituted imidazolium moiety and the Pd metal surface, plays a key role in stabilizing various active species and facilitating distinct catalytic pathways. This study provides valuable insights into the development of π-π interactions supported metal catalysts, which enhance stability and catalytic activity in advanced water-mediated synthesis applications.

Impact of formulation and home storage conditions on the content of furan and derivatives in powdered infant formula

While autoxidation of Polyunsaturated Fatty Acids (PUFAs) is a potential source of furan and its derivatives, the regulatory obligation to enrich powdered infant formulae (PIF) with some of these compounds might raise safety issues. The aim of this study was to investigate the impact of formulation and home storage conditions on the generation of furan and its derivatives in PIF. Furan, 2-methylfuran (2-MF) and 3-methylfuran (3-MF) were monitored by a validated SHS-GC-Q Exactive-Orbitrap MS method in six PIF formulated with high or low concentrations of different PUFAs (ALA, ARA, DHA), pro-oxidants (iron) and anti-oxidants (vitamins) and stored for 21 days under more or less oxidizing home storage conditions, including temperature (19 °C or 40 °C) and oxygen exposure (protected or not from ambient air). For the three compounds, the quality of the measurements in PIF was first confirmed with suitable linearity, limits of quantification, precision and recoveries. In a second step, the impact of the formulation was evaluated on six PIF commercial samples differing significantly in their composition in ALA, ARA, DHA, iron and/or vitamin E and C. While furan was quantifiable (2.8 µg/kg) in only one PIF with high content of DHA and iron and low level of vitamins, 2-MF was only quantifiable in two other PIF which were distinguished by a 15 to 20 % higher ALA content and 3-MF was not detected in any of the six PIF studied.. In a third step, the effect of storage conditions was studied on the six PIFs and the increase in storage temperature to 40 °C led to an increase of up to 33 % in the 2-MF concentration in the two PIF formulations where it was quantifiable. Nevertheless, the estimation of the Margin of Exposure (MOE) showed that the risk related to furan and its derivatives could be ruled out regardless of the formulation or storage conditions. Finally, in order to explore other derivatives and to investigate the mechanisms involved in the generation of furan compounds in PIF, a suspect screening approach was implemented on the SHS-GC-Q Exactive Orbitrap MS data. It made it possible on the one hand to point out two additional furan derivatives in PIF, 2-ethylfuran and 2-pentylfuran. On the other hand, it enabled to discuss the oxidation pathways involved in the generation of furan compounds in PIF from profiling of known PUFA oxidation markers also detected in the samples.

Ultrathin natural biotite crystals as a dielectric layer for van der Waals heterostructure applications

Biotite, an iron-rich mineral belonging to the trioctahedral mica group, is a naturally abundant layered material (LM) exhibiting attractive electronic properties for application in nanodevices. Biotite stands out as a non-degradable LM under ambient conditions, featuring high-quality basal cleavage-a significant advantage for van der Waals heterostructure (vdWH) applications. In this work, we present the micro-mechanical exfoliation of biotite down to monolayers (1Ls), yielding ultrathin flakes with large areas and atomically flat surfaces. To identify and characterize the mineral, we conducted a multi-elemental analysis of biotite using energy-dispersive spectroscopy mapping. Additionally, synchrotron x-ray fluorescence and infrared nano-spectroscopy were employed to probe its iron content and vibrational signature in few-layer form, respectively, with sensitivity to the layer number. We have also observed good morphological and structural stability in time (up to 12 months) and no important changes in their physical properties after thermal annealing processes in ultrathin biotite flakes. Conductive atomic force microscopy evaluated its electrical capacity, revealing an electrical breakdown strength of approximately 1 V nm-1. Finally, we explore the use of biotite as a substrate and encapsulating LM in vdWH applications. We have performed optical and magneto-optical measurements at low temperatures. We find that ultrathin biotite flakes work as a good substrate for 1L-MoSe2, comparable to hexagonal boron nitride flakes, but it induces a small change of the 1L-MoSe2g-factor values, most likely due to natural impurities on its crystal structure. Furthermore, our results show that biotite flakes are useful systems to protect sensitive LMs such as black phosphorus from degradation for up to 60 days in ambient air. Our study introduces biotite as a promising, cost-effective LM for the advancement of future ultrathin nanotechnologies.

Enhanced electrochemical performance of garnet Li7La3Zr2O12 electrolyte by efficient incorporation of LiCl

Garnet-type Ta-doped Li7La3Zr2O12 (LLZO) lithium-ion-conducting ceramic electrolytes has become the promising and critical candidate for developing the high-energy-density all-solid-state lithium batteries, due to the satisfied Li+ conductivity, stability against metallic lithium anode, and the feasible preparation under ambient air. Here, to further increase the lithium-ion conductivity of LLZO comparable to that of the commercial organic liquid electrolytes, lithium chloride (LiCl) is effectively introduced to synthesize the garnet-type ceramic electrolytes with the nominal composition (Li6.5La3Zr1.5Ta0.5O12)1-x–(LiCl)x (x = 0, 5mol%, 10mol%, 15mol%, 20mol%, and 25mol%) via high-temperature calcination process. The cubic structure with highly conductive performance is confirmed from X-ray diffraction measurement as well as Raman spectra analysis. Structural information is observed according to field emission scanning electron microscope equipped with energy dispersive spectrometer and density measurements. Among above investigated ceramic compositions, the prepared (Li6.5La3Zr1.5Ta0.5O12)0.85–(LiCl)0.15 ceramic electrolyte sheet sintered at 1200 °C for 12h presents the room-temperature Li-ion conductivity of 1.22 × 10−3 S·cm−1 by alternating current (AC) impedance analysis along with the corresponding activation energy of 0.262eV through Arrhenius equation calculation. The electronic conductivity measurements are also done by direct-current polarization to confirm the ionic nature for all investigated ceramics. Furthermore, the Li|(Li6.5La3Zr1.5Ta0.5O12)0.85–(LiCl)0.15 |Li symmetric batteries can possess the small interfacial resistance of 92.3 Ω cm2 and stably run for 1000 h at 0.1 mA cm−2 without a short circuit at room temperature. The hybridized lithium-sulfur battery with (Li6.5La3Zr1.5Ta0.5O12)0.85–(LiCl)0.15 electrolyte delivered excellent initial room-temperature discharge capacity of 1204mAh·g−1 and 1152 mAh·g−1 under the current density of 0.1C and 0.2C respectively, large coulombic efficiency, and great cycling stability. Moreover, the lithium-sulfur batteries also can show excellent cycling performances under different current densities and a good capacity recoverability. The above investigation results suggest that the low-melting-point LiCl incorporation in Li6.5La3Zr1.5Ta0.5O12 electrolyte is an effective measurement to synthesize the cubic and dense Li-stuff garnet ceramic sheets for the high-performance rechargeable next-generation solid-state batteries.

Unbiased temperature-related mortality estimates using weekly and monthly health data: a new method for environmental epidemiology and climate impact studies

Exposure to environmental factors has a high burden on human health, with millions of premature annual deaths associated with the short-term health effects of ambient temperatures and air pollution. However, direct estimations of exposure-related mortality from real data are still not available in most parts of the world, especially in low-resource settings, due to the unavailability of daily health records to calibrate epidemiological models. In this study, we have filled the crucial gap in available direct estimations by developing a method to make valid inference for the relationship between exposure and response data that uses only exposure and temporally aggregated response data. We provided the mathematical derivation of the method, and compared the results by using simulations applied to daily temperature and daily, weekly, and monthly mortality data. The method was then applied to the newly created database of the EARLY-ADAPT project. The daily and weekly models produced similar and unbiased estimates of the temperature-related relative risks and attributable mortality, with only slightly more imprecision in the weekly model. Even the estimates of the monthly model were unbiased when using enough data, although at the expense of a substantial increase in variability. The real data analysis showed that the similarity between the regional values of two aggregation models increased with the number of years and regions of the dataset, and decreased with the difference in their degree of temporal aggregation. Our method opens the door to conducting epidemiological studies in low-resource settings, where access to daily health data is not possible. Moreover, it allows accurate estimation of the short-term health effects of environmental exposures in near-real time, when daily health data are still not available, such as in the estimation of the mortality burden of recent record-breaking heat episodes. Overall, our method represents an important new approach to how the public health community can use data to create new evidence for research, translation and policy making. European Research Council (ERC).

Spatial Analysis of Sulfur Dioxide (SO2) and Nitrogen Dioxide (NO2) Distribution Using Getis-Ord Gi* in DKI Jakarta Region, Indonesia

Abstract The increasing mobility of population and industry is the main problem in this study, so it will affect the spatial pattern in the distribution of pollutants. The parameters to measure air quality are Sulfur Dioxide and Nitrogen Dioxide. This study aims to (1) analyze air quality distribution patterns with SO2 and NO2 concentration parameters in the DKI Jakarta area in 2021, (2) analyze ambient air quality distribution patterns based on air quality threshold values, and (3) analyze the spatial distribution of SO2 and NO2 in the DKI Jakarta area in 2021. The data used for this research is the average concentration data of SO2 and NO2 pollutants in DKI Jakarta in 2021. This research uses the interpolation method using Inverse Distance Weighting and Getis-Ord Gi*. The results of this research show that the concentration of pollutants that have been interpolated using Inverse Distance Weighting produces higher NO2 than SO2. From the interpolated image, a Hot Spot analysis (Getis-Ord Gi*) was conducted. This analysis showed significant clustering of nearest neighbors, with high concentrations of SO2 in East Jakarta and NO2 in West Jakarta. Therefore, air quality needs to be monitored and managed to maintain environmental stability.

The impact of green space on nonaccidental and cause-specific mortality in the Adventist Health Study-2 population.

There is growing interest in evaluating the long-term health effects of neighborhood environments, particularly green space. However, only a limited body of research further incorporates multiple ambient air pollutants. This study looked at the relationship between green space, as measured by the Normalized Difference Vegetation Index, and mortality adjusted by key confounders in the Adventist Health Study-2, a longitudinal cohort study from 2002 to 2015, across the contiguous United States (N = 67,400). We used Cox proportional hazard regression models to assess the risk of nonaccidental, cardiovascular disease (CVD), ischemic heart disease (IHD), and respiratory disease mortality from green space around subjects' home address under multiple covariate and pollutant adjustments. We found a 0.1 unit increase in the Normalized Difference Vegetation Index was associated with nonaccidental (hazard ratio [HR]: 0.96 [95% confidence interval (CI): 0.93, 0.99]), CVD (HR: 0.94 [95% CI: 0.90, 0.98]), and IHD (HR: 0.87 [95% CI: 0.81, 0.94]) mortality, with the greatest precision in fully adjusted three-pollutant models using the 1000-m buffer. Effect estimates were strengthened in urban areas, when incorporating seasons, and for females. However, all associations between green space and respiratory mortality were null. This study supports evidence that increased neighborhood green space is inversely associated with nonaccidental, CVD, and IHD mortality, where the inclusion of multiple environmental covariates had a greater impact on effect estimate magnitude and precision than adjustment by individual lifestyle and health factors.

The effect of temperature on the Emission Factor of air emissions from pyrolysis of used tyres

Used tyres pyrolysis is an efficient solid waste management strategy for used tyres and a growing method of fuel oil production. However, the impact of air emissions associated at different temperature on ambient air quality has not been determined. To solve this problem, a pyrolysis fixed bed reactor and a condensing unit for separating liquid from produced gas were designed and constructed. 0.20 kg of used tyres were pyrolysed in the reactor and air emissions from the reactor chamber was characterized for air pollutants using the E-instrument E8500. Using a combination of measured mass of pollutants, mass of tyre pyrolzed and time taken during pyrolysis, Emission Factors of the air pollutants were established from the study at 200 °C, 300 °C and 400 °C. The concentration measured between 200 °C - 400 °C were in the range of 15 -7497 mg/m3, 0 – 4680 mg/m3, 38.25 – 103, 277.76 mg/m3 and 2 – 293 mg/m3 for CO, NOx, HC and H2S respectively. The developed emission factors were in the range of 16.52 – 8370.04 g kg-1, 0 – 4470.26 g kg-1, 42.126 – 104,055.9 g kg-1 and 2.20 – 322.69 g kg-1. The designed and constructed pyrolysis reactor and condenser unit were effective for used tyre pyrolysis while the measured air pollutants concentration were higher for all pollutants except H2S using the Federal Ministry of Environment (FEPA, 1991) standard. Hence, it is necessary to carry out further studies on air pollution control from waste tyre pyrolysis at lower temperature.

Association of ambient air pollution with cognitive functioning and markers of structural brain damage: The Maastricht study

IntroductionGiven the absence of curative interventions and the rising global incidence of dementia, research is increasingly focusing on lifestyle factors for prevention. However, identifying shared environmental risk for dementia, next to individual factors, is crucial for optimal risk reduction strategies. Therefore, in the present study we investigated the association between air pollution, cognitive functioning, and markers of structural brain damage. MethodsWe used cross-sectional data from 4,002 participants of The Maastricht Study on volumetric markers of brain integrity (white and grey matter volume, cerebrospinal fluid volume, white matter hyperintensities volume, presence of cerebral small vessel disease) and cognitive functioning (memory, executive functioning and attention, processing speed, overall cognition). Individuals were matched by postal code of residence to nationwide data on air pollution exposure (particulate matter < 2.5 μm (PM2.5), particulate matter <10 μm (PM10), nitrogen dioxide (NO2), soot). Potentia linear and non-linear associations were investigated with linear, logistic, and restricted cubic splines regression. All analyses were adjusted for demographic characteristics and a compound score of modifiable dementia risk and protective factors. ResultsExposure to air pollutants was not related to cognitive functioning and most brain markers. We found curvilinear relationships between high PM2.5 exposures and grey matter and cerebrospinal fluid volume. Participants in the low and high range of exposure had lower grey matter volume. Higher cerebrospinal fluid volumes were only associated with high range of exposure, independent of demographic and individual modifiable dementia risk factors. After additional post hoc analyses, controlling for urbanicity, the associations for grey matter volume became non-significant. In men only, higher exposure to all air pollutants was associated with lower white matter volumes. No significant associations with white matter hyperintensities volume or cerebral small vessel disease were observed. DiscussionOur findings suggest that higher PM2.5 exposure is associated with more brain atrophy.