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To assess the exposure of patrons and workers to secondhand cannabis smoke in the smoking lounge of a cannabis store, we measured airborne PM2.5, cannabinoids, and nicotine in a cannabis store and a nearby coffee shop. PM2.5 concentration was measured with laser photometers. PM2.5 samples were collected on filters and cannabinoids were quantified by liquid chromatography with tandem mass spectroscopy and nicotine was quantified by gas chromatography. Activity and demographic data were recorded. The average PM2.5 concentration over nine experiments conducted between September 2018 and August 2019 was 840 (standard deviation of 674 µg/m3). Concentrations of THC, CBD, and CBN in the particulate matter averaged 79.0 µg/m3, 0.708 ng/m3, and 8.60 ng/m3, respectively. Nicotine concentrations were below the level of quantification. Although a variety of consumption methods were observed, 91% of the observed consumption events were smoking. The business installed a ventilation system halfway through our study.  Before the ventilation system was installed, the average PM2.5 was 905 µg/m3, afterwards it was 795 µg/m3.  This 12.2% decrease was not statistically significant.  Our results show that smoking cannabis indoors can create high concentrations of particulate air pollution that are known to cause adverse health effects.

To assess the exposure of patrons and workers to secondhand cannabis smoke in the smoking lounge of a cannabis store, we measured airborne PM2.5, cannabinoids, and nicotine in a cannabis store and a nearby coffee shop. PM2.5 concentration was measured with laser photometers. PM2.5 samples were collected on filters and cannabinoids were quantified by liquid chromatography with tandem mass spectroscopy and nicotine was quantified by gas chromatography. Activity and demographic data were recorded. The average PM2.5 concentration over nine experiments conducted between September 2018 and August 2019 was 840 (standard deviation of 674 µg/m3). Concentrations of THC, CBD, and CBN in the particulate matter averaged 79.0 µg/m3, 0.708 ng/m3, and 8.60 ng/m3, respectively. Nicotine concentrations were below the level of quantification. Although a variety of consumption methods were observed, 91% of the observed consumption events were smoking. The business installed a ventilation system halfway through our study.  Before the ventilation system was installed, the average PM2.5 was 905 µg/m3, afterwards it was 795 µg/m3.  This 12.2% decrease was not statistically significant.  Our results show that smoking cannabis indoors can create high concentrations of particulate air pollution that are known to cause adverse health effects.

Particulate transport from surfaces governs a variety of phenomena including fungal spore dispersal, bioaerosol transmission, and self-cleaning. Here, we report a previously unidentified mechanism governing passive particulate removal from superhydrophobic surfaces, where a particle coalescing with a water droplet (similar to 10 to similar to 100 mu m) spontaneously launches. Compared to previously discovered coalescence-induced binary droplet jumping, the reported mechanism represents a more general capillary-inertial dominated transport mode coupled with particle/droplet properties and is typically mediated by rotation in addition to translation. Through wetting and momentum analyses, we show that transport physics depends on particle/droplet density, size, and wettability. The observed mechanism presents a simple and passive pathway to achieve self-cleaning on both artificial as well as biological materials as confirmed here with experiments conducted on butterfly wings, cicada wings, and clover leaves. Our findings provide insights into particle-droplet interaction and spontaneous particulate transport, which may facilitate the development of functional surfaces for medical, optical, thermal, and energy applications.

Introduction: Cannabis regulation and use are undergoing dramatic changes. New cannabis products and new ways of using are emerging.  These changes have the potential to affect exposure to cannabis smoke and other emissions from cannabis use.  Cannabis smoke is known to contain fine, respirable particles (PM2.5) and other toxicants and carcinogens. Objectives: To assess the potential for exposure to PM2.5 from novel cannabis aerosols, we measured PM2.5 concentrations in a cannabis retail outlet (a dispensary) that permits on-site consumption of cannabis via non-combustion methods including vaporization and dabbing.Methods: PM2.5 concentrations in the dispensary were measured around the clock for five weeks using 2 laser photometer instruments (429,604 data points collected over 38.69 days).  The instruments were calibrated gravimetrically using a controlled cigarette generation system at regular intervals during the experiment. Outdoor PM2.5 concentrations were taken from a nearby EPA monitoring station.Results: The average PM2.5 concentration in the dispensary retail space, during business hours, was 84 ± 124 µg/m3, with a median of 47 µg/m3.  The average PM2.5 concentration when the business was closed was 3 ± 7 µg/m3 with a median of 2 µg/m3.   The highest daily concentrations correlated with the hours with the most customers.Conclusion: Our results suggest that the use of cannabis products indoors, even by non-combustion methods, increases the concentration of PM2.5. These findings are of concern to the public health because the business studied was in compliance with local laws and because PM2.5 exposure is a known cause of cardiopulmonary and metabolic disease.

Introduction: Cannabis regulation and use are undergoing dramatic changes. New cannabis products and new ways of using are emerging.  These changes have the potential to affect exposure to cannabis smoke and other emissions from cannabis use.  Cannabis smoke is known to contain fine, respirable particles (PM2.5) and other toxicants and carcinogens. Objectives: To assess the potential for exposure to PM2.5 from novel cannabis aerosols, we measured PM2.5 concentrations in a cannabis retail outlet (a dispensary) that permits on-site consumption of cannabis via non-combustion methods including vaporization and dabbing.Methods: PM2.5 concentrations in the dispensary were measured around the clock for five weeks using 2 laser photometer instruments (429,604 data points collected over 38.69 days).  The instruments were calibrated gravimetrically using a controlled cigarette generation system at regular intervals during the experiment. Outdoor PM2.5 concentrations were taken from a nearby EPA monitoring station.Results: The average PM2.5 concentration in the dispensary retail space, during business hours, was 84 ± 124 µg/m3, with a median of 47 µg/m3.  The average PM2.5 concentration when the business was closed was 3 ± 7 µg/m3 with a median of 2 µg/m3.   The highest daily concentrations correlated with the hours with the most customers.Conclusion: Our results suggest that the use of cannabis products indoors, even by non-combustion methods, increases the concentration of PM2.5. These findings are of concern to the public health because the business studied was in compliance with local laws and because PM2.5 exposure is a known cause of cardiopulmonary and metabolic disease.

Permafrost-affected soils of the Arctic account for 70% or 727 Pg of the soil organic carbon (C) stored in the northern circumpolar permafrost region and therefore play a major role in the global C cycle. Most studies on the budgeting of C storage and the quality of soil organic matter (OM; SOM) in the northern circumpolar region focus on bulk soils. Thus, although there is a plethora of assumptions regarding differences in terms of C turnover or stability, little knowledge is available on the mechanisms stabilizing organic C in Arctic soils besides impaired decomposition due to low temperatures. To gain such knowledge, we investigated soils from Samoylov Island in the Lena River delta with respect to the composition and distribution of organic C among differently stabilized SOM fractions. The soils were fractionated according to density and particle size to obtain differently stabilized SOM fractions differing in chemical composition and thus bioavailability. To better understand the chemical alterations from plant-derived organic particles in these soils rich in fibrous plant residues to mineral-associated SOM, we analyzed the elemental, isotopic and chemical composition of particulate OM (POM) and clay-sized mineral-associated OM (MAOM). We demonstrate that the SOM fractions that contribute with about 17 kgCm(-3) for more than 60% of the C stock are highly bioavailable and that most of this labile C can be assumed to be prone to mineralization under warming conditions. Thus, the amount of relatively stable, small occluded POM and clay-sized MAOM that currently accounts with about 10 kgCm(-3) for about 40% of the C stock will most probably be crucial for the quantity of C protected from mineralization in these Arctic soils in a warmer future. Using delta N-15 as a proxy for nitrogen (N) balances indicated an important role of N inputs by biological N fixation, while gaseous N losses appeared less important. However, this could change, as with about 0.4 kgNm(-3)

Permafrost-affected soils of the Arctic account for 70% or 727 Pg of the soil organic carbon (C) stored in the northern circumpolar permafrost region and therefore play a major role in the global C cycle. Most studies on the budgeting of C storage and the quality of soil organic matter (OM; SOM) in the northern circumpolar region focus on bulk soils. Thus, although there is a plethora of assumptions regarding differences in terms of C turnover or stability, little knowledge is available on the mechanisms stabilizing organic C in Arctic soils besides impaired decomposition due to low temperatures. To gain such knowledge, we investigated soils from Samoylov Island in the Lena River delta with respect to the composition and distribution of organic C among differently stabilized SOM fractions. The soils were fractionated according to density and particle size to obtain differently stabilized SOM fractions differing in chemical composition and thus bioavailability. To better understand the chemical alterations from plant-derived organic particles in these soils rich in fibrous plant residues to mineral-associated SOM, we analyzed the elemental, isotopic and chemical composition of particulate OM (POM) and clay-sized mineral-associated OM (MAOM). We demonstrate that the SOM fractions that contribute with about 17 kgCm(-3) for more than 60% of the C stock are highly bioavailable and that most of this labile C can be assumed to be prone to mineralization under warming conditions. Thus, the amount of relatively stable, small occluded POM and clay-sized MAOM that currently accounts with about 10 kgCm(-3) for about 40% of the C stock will most probably be crucial for the quantity of C protected from mineralization in these Arctic soils in a warmer future. Using delta N-15 as a proxy for nitrogen (N) balances indicated an important role of N inputs by biological N fixation, while gaseous N losses appeared less important. However, this could change, as with about 0.4 kgNm(-3)

Discrete Element Method (DEM) is a numerical process that uses the concept of particulate mechanics, and it is capable of modelling the discontinuous response of particulate materials. It was utilized in this research for agricultural and geotechnical engineering applications. In an agricultural engineering application, the particle contact microparameters of various crop residues - canola, corn, flax, oats, and wheat - and their interfaces with soil were characterized. These microparameters can be used to improve the reliability of soil-tool-residue DEM models, which in turn is important for the design of high-performance soil-engaging tools. Microparameters for the materials were determined by using a calibration methodology. Laboratory tests were initially performed to obtain information on the macroscopic behavior of the material. Then, discrete element models of the tests were generated to back-calculate the microparameters by simulating the laboratory test results. Linear contact model, with particle stiffness and friction as microparameters, was used to describe the behavior of the interactions between crop residue particles and of the soil-residue interfaces. Ring shear test was conducted to identify the internal friction angle of the crop residues, while direct shear test was carried out to measure the friction angle of the soil-residue interfaces. The DEM models of ring shear and direct shear tests were then developed and used in simulating the measured test results. The DEM simulations of both tests were found to efficiently calibrate the microparameters for residue-residue and soil-residue interactions. In a geotechnical engineering application, the microparameters of the main constituents of an earth fill dam were characterized by conducting DEM simulations of triaxial and large-scale direct shear tests. These microparameters were utilized in developing a landslide DEM model that simulated the observed excessive movements (landslide) in the dam. Validat

Urbanisation largely consists of removing native vegetation. Plants that remain interact with air quality in complex ways. Pollutants can be detrimental to plant growth; plants sometimes reduce air quality, yet some species also improve it through phytoremediation. A common pollutant of concern to human health in urban areas is particulate matter (PM), small particles of solid or liquid. Our study compared roadside moss turfs with leaves of a common Australian tree species, Pittosporum undulatum, in their ability to capture PM along an urban gradient. We sampled nine sites, three in each of three levels of urbanisation: low, medium, and high according to road type (freeway, suburban road, quiet peri-urban road). In addition, we deployed a PM monitor over a two-week period in one site of each urban level to provide concentrations of PM2.5. We used chlorophyll fluorescence (Fv/Fm; maximum quantum yield of photosystem II) as a measure of plant stress. We extracted PM in three size fractions using a filtration and washing technique with water and chloroform. Site averages for moss turfs were between 5.60 and 33.00 mg per g dry weight for total PM compared to between 2.15 and 10.24 mg per g dry weight for the tree leaves. We found that moss was more sensitive to increasing urbanisation, both in terms of trapping proportionately more PM than the leaves, and also in terms of photosynthetic stress, with moss Fv/Fm declining by a site average of 40% from low to high urban "class" (0.76 to 0.45). Our study highlights the stressors potentially limiting moss persistence in cities. It also demonstrates its ability to trap PM, a trait that could be useful in urban applications relating to urban greening or air quality.

Discrete Element Method (DEM) is a numerical process that uses the concept of particulate mechanics, and it is capable of modelling the discontinuous response of particulate materials. It was utilized in this research for agricultural and geotechnical engineering applications. In an agricultural engineering application, the particle contact microparameters of various crop residues - canola, corn, flax, oats, and wheat - and their interfaces with soil were characterized. These microparameters can be used to improve the reliability of soil-tool-residue DEM models, which in turn is important for the design of high-performance soil-engaging tools. Microparameters for the materials were determined by using a calibration methodology. Laboratory tests were initially performed to obtain information on the macroscopic behavior of the material. Then, discrete element models of the tests were generated to back-calculate the microparameters by simulating the laboratory test results. Linear contact model, with particle stiffness and friction as microparameters, was used to describe the behavior of the interactions between crop residue particles and of the soil-residue interfaces. Ring shear test was conducted to identify the internal friction angle of the crop residues, while direct shear test was carried out to measure the friction angle of the soil-residue interfaces. The DEM models of ring shear and direct shear tests were then developed and used in simulating the measured test results. The DEM simulations of both tests were found to efficiently calibrate the microparameters for residue-residue and soil-residue interactions. In a geotechnical engineering application, the microparameters of the main constituents of an earth fill dam were characterized by conducting DEM simulations of triaxial and large-scale direct shear tests. These microparameters were utilized in developing a landslide DEM model that simulated the observed excessive movements (landslide) in the dam. Validat

Istraživanje u okviru doktorske disertacije obuhvata uzorkovanja inhalativne frakcije praškastih materija generisane u zubotehničkoj laboratoriji i procesom brušenja čelika EN 90MnCrV8, primenu savremenih metodologija uzorkovanja, analizu uzorka laserskom difrakcijom i analizom slike, zasnovanom na mikrografijama skenirajućeg elektronskog mikroskopa i statističku obradu podataka. Osnovni cilj istraživanja je razvoj funkcionalnog modela za evaluaciju rezultata merenja karakteristika praškastih materija, koji je obuhvatio identifikaciju, procenu i vrednovanje karakteristika prahova, u cilju unapređenja tačnosti rezultata u vezi sa karakterizacijom čestica. Složena geometrija čestica je ispitana analizom 14 parametara, 6 koji definišu veličinu i 8 parametara koji opisuju morfološke karakteristike, upotrebom dva softvera za analizu slike. Dobijeni rezultati obrađeni su primenom metode analize glavnih komponenti i hijerarhijske klaster analize, čime se prevazišao problem subjektivnog prilaza i izvršila redukcija i selekcije reprezantativnih parametara na osnovu kojih se može dovoljno dobro definisati i okarakterisati uzorak., Тhis PhD thesis presented the development of the functional model for evaluation оf measuring results of powder materials’ characteristics, which involved the identification, assessment and evaluation of particles characteristics, in order to improve the accuracy of the results. Sampling of inhalation fraction of the powder materials’ was done in the dental laboratory and grinding process of the EN 90MnCrV8 steel. Particle analysis was performed whit laser diffraction and image analysis based on micrographics from scanning electron microscopy and data were statistically analyzed. The complex particle geometry was examined by analyzing 14 parameters, 6 which define the size and 8 parameters that describe the morphological characteristics, using two image analysis software. To deal with a large number of the numerical parameters used to characterise the particle geometry and the nonlinear relationships among these parameters, principal component analysis (PCA) and hierarchical cluster analysis (CA) algorithm was applied to identify representative numerical descriptors within each group.

In the past several decades there has been an increased interest in sand, dust, and ash particulates ingestion study for gas turbine engine applications. Recently, there has been an increase in commercial and military fleets operating in medium to highly dusty environments, such as areas in Africa, the Middle East, and Asia. Dusty environments can cause blockage in turbine cooling circuits which can lead to early engine maintenance or removals. Ingested debris can melt, forming glassy or molten deposits on various hot section components in gas turbine engines. This thesis evaluates the onset of deposit formation using an experimental rig to perform testing in high temperature environment. In general, deposits on turbine components can affect the operating capacity and the overall operating efficiency of gas turbine engines. Particulate ingestion events can be catastrophic and cost millions of dollars in maintenance and repairs. The experimental work in this thesis focused only on quantifying the initial deposit formation in high temperature environment to aid in the development of resilient engine design and operational diagnostics. Testing was performed using HASTELLOY® X coupons and Arizona Road Dust with main gas flow temperatures between 1050°C and 1100°C. Arizona Road Dust sample with sizing between 2µm and 40µm were used for experimental testing. The sensitivity of the initial deposit formation on cooled HASTELLOY® X coupon surface was investigated by using an inline air heater. Three cooling test conditions: no cooling, 500°C cooling, and 250°C cooling, were used to alter the surface temperature of the coupon during testing. Results from testing indicated cooling test conditions used have a small impact on deposit formation.

This project intends to present a Particle Number measurement guide for internal combustion engines installed in Inland Waterways Vessels (among others) for good repeatability and reliable results. The understanding of particles is crucial, as well as which measurement equipment is available. Este proyecto tiene como objetivo presentar una guía de medición del PN para ayudar a mejorar la repetitividad y aumentar la validez de los resultados en etapas de investigación, para motores instalados en buques que navegan en vías navegables interiores, y también para buques más grandes en caso de que sea necesario. La metodología utilizada consistirá en analizar las Regulaciones Europeas existentes para NRMM, realizar una comparación entre los equipos de medición del PN en diferentes pruebas de motores en el laboratorio de motores de Wärtsilä, y discutir algunas incertidumbres con las Autoridades correspondientes. La investigación bibliográfica también será necesaria para aclarar conceptos químicos con respecto a las partículas.

Understanding the effect of wildfire smoke exposure on human health represents a unique interdisciplinary challenge to the scientific community. Population health studies indicate that wildfire smoke is a risk to human health and increases the healthcare burden of smoke-impacted areas. However, wildfire smoke composition is complex and dynamic, making characterization and modeling difficult. Furthermore, current efforts to study the effect of wildfire smoke are limited by availability of air quality measures and inconsistent air quality reporting among researchers. To help address these issues, we conducted a substantive review of wildfire smoke effects on population health, wildfire smoke exposure in occupational health, and experimental wood smoke exposure. Our goal was to evaluate the current literature on wildfire smoke and highlight important gaps in research. In particular we emphasize long-term health effects of wildfire smoke, recovery following wildfire smoke exposure, and health consequences of exposure in children.

Understanding the effect of wildfire smoke exposure on human health represents a unique interdisciplinary challenge to the scientific community. Population health studies indicate that wildfire smoke is a risk to human health and increases the healthcare burden of smoke-impacted areas. However, wildfire smoke composition is complex and dynamic, making characterization and modeling difficult. Furthermore, current efforts to study the effect of wildfire smoke are limited by availability of air quality measures and inconsistent air quality reporting among researchers. To help address these issues, we conducted a substantive review of wildfire smoke effects on population health, wildfire smoke exposure in occupational health, and experimental wood smoke exposure. Our goal was to evaluate the current literature on wildfire smoke and highlight important gaps in research. In particular we emphasize long-term health effects of wildfire smoke, recovery following wildfire smoke exposure, and health consequences of exposure in children.

Severe trace metal pollution due to industrial effluents releases was found in Jiulong River Estuary, Southern China. In this study, water samples were collected during effluent release events to study the dynamic changes of environmental conditions and metal partitioning among dissolved, particulate and colloidal phases controlled by estuarine mixing. Intermittent effluent discharges during low tide caused decreasing pH and dissolved oxygen, and induced numerous suspended particulate materials and dissolved organic carbon to the estuary. Different behaviors of Cu, Zn, Ni, Cr and Pb in the dissolved fraction against the conservative index salinity indicated different sources, e.g., dissolved Ni from the intermittent effluent. Although total metal concentrations increased markedly following effluent discharges, Cu, Zn, Cr, Pb were predominated by the particulate fraction. Enhanced adsorption onto particulates in the mixing process resulted in elevated partitioning coefficient (Kd) values for Cu and Zn, and the particle concentration effect was not obvious under such anthropogenic impacts. Colloidal proportion of these metals (especially Cu and Zn) showed positive correlations with dissolved or colloidal organic carbon, suggesting the metal-organic complexation. However, the calculated colloidal partitioning coefficients were relatively constant, indicating the excess binding capacity. Overall, the intermittent effluent discharge altered the particulate/dissolved and colloidal/soluble phase partitioning process and may further influence the bioavailability and potential toxicity to aquatic organisms. © 2016 Elsevier Ltd. All rights reserved.

Severe trace metal pollution due to industrial effluents releases was found in Jiulong River Estuary, Southern China. In this study, water samples were collected during effluent release events to study the dynamic changes of environmental conditions and metal partitioning among dissolved, particulate and colloidal phases controlled by estuarine mixing. Intermittent effluent discharges during low tide caused decreasing pH and dissolved oxygen, and induced numerous suspended particulate materials and dissolved organic carbon to the estuary. Different behaviors of Cu, Zn, Ni, Cr and Pb in the dissolved fraction against the conservative index salinity indicated different sources, e.g., dissolved Ni from the intermittent effluent. Although total metal concentrations increased markedly following effluent discharges, Cu, Zn, Cr, Pb were predominated by the particulate fraction. Enhanced adsorption onto particulates in the mixing process resulted in elevated partitioning coefficient (Kd) values for Cu and Zn, and the particle concentration effect was not obvious under such anthropogenic impacts. Colloidal proportion of these metals (especially Cu and Zn) showed positive correlations with dissolved or colloidal organic carbon, suggesting the metal-organic complexation. However, the calculated colloidal partitioning coefficients were relatively constant, indicating the excess binding capacity. Overall, the intermittent effluent discharge altered the particulate/dissolved and colloidal/soluble phase partitioning process and may further influence the bioavailability and potential toxicity to aquatic organisms. © 2016 Elsevier Ltd. All rights reserved.

The combustion process of power generation plants originates particulates. There are different technologies to collecting particulate such as electrostatic precipitators (ESPs) or fabric filters. Currently, these ESPs take 25 or 35 years in service and if the performance expectations of their Plants are positives, improving investments required which can adapt to the new particulate emission limits becoming more stringent. This paper analyzes an alternative means great savings in investment costs; Conversion of the existing ESP casing to a Pulse Jet fabric filter. This study also presents a real case, implementing this conversion with good results in unit of 660 MW power plants of Italy.

The combustion process of power generation plants originates particulates. There are different technologies to collecting particulate such as electrostatic precipitators (ESPs) or fabric filters. Currently, these ESPs take 25 or 35 years in service and if the performance expectations of their Plants are positives, improving investments required which can adapt to the new particulate emission limits becoming more stringent. This paper analyzes an alternative means great savings in investment costs; Conversion of the existing ESP casing to a Pulse Jet fabric filter. This study also presents a real case, implementing this conversion with good results in unit of 660 MW power plants of Italy., El proceso de combustión de las Centrales Térmicas convencionales origina emisiones de partículas. Existen distintas tecnologías de captación de partículas, como los precipitadores electrostáticos (PE) o los filtros de mangas. Hoy en día, estos precipitadores electrostáticos llevan 25 o 35 años en servicio y si las expectativas de funcionamiento de sus Centrales son positivas, se requieren inversiones de mejora que permitan adaptarse a los nuevos límites de emisión de partículas cada vez más estrictos. El presente artículo analiza una alternativa que supone grandes ahorros en los costes de inversión, transformando el precipitador electrostático en un filtro de mangas con sistema de limpieza por impulsos de aire a presión (pulse-jet), aprovechando la estructura existente. Este estudio presenta también un caso real, poniendo en práctica esta conversión con buenos resultados en una unidad de 660 MW de una central térmica de Italia.

The combustion process of power generation plants originates particulates. There are different technologies to collecting particulate such as electrostatic precipitators (ESPs) or fabric filters. Currently, these ESPs take 25 or 35 years in service and if the performance expectations of their Plants are positives, improving investments required which can adapt to the new particulate emission limits becoming more stringent. This paper analyzes an alternative means great savings in investment costs; Conversion of the existing ESP casing to a Pulse Jet fabric filter. This study also presents a real case, implementing this conversion with good results in unit of 660 MW power plants of Italy., El proceso de combustión de las Centrales Térmicas convencionales origina emisiones de partículas. Existen distintas tecnologías de captación de partículas, como los precipitadores electrostáticos (PE) o los filtros de mangas. Hoy en día, estos precipitadores electrostáticos llevan 25 o 35 años en servicio y si las expectativas de funcionamiento de sus Centrales son positivas, se requieren inversiones de mejora que permitan adaptarse a los nuevos límites de emisión de partículas cada vez más estrictos. El presente artículo analiza una alternativa que supone grandes ahorros en los costes de inversión, transformando el precipitador electrostático en un filtro de mangas con sistema de limpieza por impulsos de aire a presión (pulse-jet), aprovechando la estructura existente. Este estudio presenta también un caso real, poniendo en práctica esta conversión con buenos resultados en una unidad de 660 MW de una central térmica de Italia.

The combustion process of power generation plants originates particulates. There are different technologies to collecting particulate such as electrostatic precipitators (ESPs) or fabric filters. Currently, these ESPs take 25 or 35 years in service and if the performance expectations of their Plants are positives, improving investments required which can adapt to the new particulate emission limits becoming more stringent. This paper analyzes an alternative means great savings in investment costs; Conversion of the existing ESP casing to a Pulse Jet fabric filter. This study also presents a real case, implementing this conversion with good results in unit of 660 MW power plants of Italy.

The combustion process of power generation plants originates particulates. There are different technologies to collecting particulate such as electrostatic precipitators (ESPs) or fabric filters. Currently, these ESPs take 25 or 35 years in service and if the performance expectations of their Plants are positives, improving investments required which can adapt to the new particulate emission limits becoming more stringent. This paper analyzes an alternative means great savings in investment costs; Conversion of the existing ESP casing to a Pulse Jet fabric filter. This study also presents a real case, implementing this conversion with good results in unit of 660 MW power plants of Italy., El proceso de combustión de las Centrales Térmicas convencionales origina emisiones de partículas. Existen distintas tecnologías de captación de partículas, como los precipitadores electrostáticos (PE) o los filtros de mangas. Hoy en día, estos precipitadores electrostáticos llevan 25 o 35 años en servicio y si las expectativas de funcionamiento de sus Centrales son positivas, se requieren inversiones de mejora que permitan adaptarse a los nuevos límites de emisión de partículas cada vez más estrictos. El presente artículo analiza una alternativa que supone grandes ahorros en los costes de inversión, transformando el precipitador electrostático en un filtro de mangas con sistema de limpieza por impulsos de aire a presión (pulse-jet), aprovechando la estructura existente. Este estudio presenta también un caso real, poniendo en práctica esta conversión con buenos resultados en una unidad de 660 MW de una central térmica de Italia.

Recently, scientists have made significant progress in the development of immunotherapeutics that correct aberrant, autoimmune responses. Yet, concerns about the safety, efficacy, and wide scale applicability continue to hinder use of contemporary, immunology-based strategies. There is a clear need for therapies that finely control molecular and cellular elements of the immune system. Biomaterial engineers have taken up this challenge to develop therapeutics with selective spatial and temporal control of immune cells. In this review, we introduce the immunology of autoimmune disorders, survey the current therapeutic strategies for autoimmune diseases, and highlight the ongoing research efforts to engineer the immune system using biomaterials, for positive therapeutic outcomes in treatment of autoimmune disorders.

Atmospheric corrosion of printed circuit board assembly (PCBA) surface is synergistically affected by many factors, such as temperature (T), relative humidity (RH), chemical composition of atmospheric contaminants and electric field. In this work, a prototype rotating impactor was developed to deposit sub-micrometer atmospheric particles contaminants on surface insulation resistance (SER) patterns for a minimum of 24 hours. The test boards were exposed to varying RH conditions (30→99→30% RH) with different RH ramping rates and T. Water film formation was monitored by impedance response at 1kHz, whereas the corrosive behavior was investigated under 5V DC bias. Particles chemical composition of the water-soluble (WS) inorganic fraction and mono- and di-carboxylic acids were characterized by means of ion chromatography from PM2.5 samples. Thin electrolytic-layer formation due to deliquescence of WS compounds (about 40% in mass) abruptly decreased the impedance measured during increasing RH ramp, whereas it showed a hysteresis comparing with the response at decreasing RH ramp. The RH value at which sharp change in impedance observed was affected by T of the surrounding air and RH ramping rate. The formation of conductive layers leads to tin corrosion far below the condensing conditions. High leakage current values were observed even below 70% RH due to particles hygroscopicity and SEM-EDS analyses highlighted tin migration.

The combustion process of power generation plants originates particulates. There are different technologies to collecting particulate such as electrostatic precipitators (ESPs) or fabric filters. Currently, these ESPs take 25 or 35 years in service and if the performance expectations of their Plants are positives, improving investments required which can adapt to the new particulate emission limits becoming more stringent. This paper analyzes an alternative means great savings in investment costs; Conversion of the existing ESP casing to a Pulse Jet fabric filter. This study also presents a real case, implementing this conversion with good results in unit of 660 MW power plants of Italy., El proceso de combustión de las Centrales Térmicas convencionales origina emisiones de partículas. Existen distintas tecnologías de captación de partículas, como los precipitadores electrostáticos (PE) o los filtros de mangas. Hoy en día, estos precipitadores electrostáticos llevan 25 o 35 años en servicio y si las expectativas de funcionamiento de sus Centrales son positivas, se requieren inversiones de mejora que permitan adaptarse a los nuevos límites de emisión de partículas cada vez más estrictos. El presente artículo analiza una alternativa que supone grandes ahorros en los costes de inversión, transformando el precipitador electrostático en un filtro de mangas con sistema de limpieza por impulsos de aire a presión (pulse-jet), aprovechando la estructura existente. Este estudio presenta también un caso real, poniendo en práctica esta conversión con buenos resultados en una unidad de 660 MW de una central térmica de Italia.

Severe trace metal pollution due to industrial effluents releases was found in Jiulong River Estuary, Southern China. In this study, water samples were collected during effluent release events to study the dynamic changes of environmental conditions and metal partitioning among dissolved, particulate and colloidal phases controlled by estuarine mixing. Intermittent effluent discharges during low tide caused decreasing pH and dissolved oxygen, and induced numerous suspended particulate materials and dissolved organic carbon to the estuary. Different behaviors of Cu, Zn, Ni, Cr and Pb in the dissolved fraction against the conservative index salinity indicated different sources, e.g., dissolved Ni from the intermittent effluent. Although total metal concentrations increased markedly following effluent discharges, Cu, Zn, Cr, Pb were predominated by the particulate fraction. Enhanced adsorption onto particulates in the mixing process resulted in elevated partitioning coefficient (Kd) values for Cu and Zn, and the particle concentration effect was not obvious under such anthropogenic impacts. Colloidal proportion of these metals (especially Cu and Zn) showed positive correlations with dissolved or colloidal organic carbon, suggesting the metal-organic complexation. However, the calculated colloidal partitioning coefficients were relatively constant, indicating the excess binding capacity. Overall, the intermittent effluent discharge altered the particulate/dissolved and colloidal/soluble phase partitioning process and may further influence the bioavailability and potential toxicity to aquatic organisms.

Poster presentation at The 18th International Conference of International Society for Respiratory Protection, 7-11 November 2016, Yokohama, Japan.

Poster presentation made at the 20th ETH-Conference on Combustion Generated Nanoparticles, 13-16 June 2016, Zurich, Switzerland. Aim: Ultrafine diesel engine emissions are known to cause adverse health impacts including lung cancer, cardiovascular and irritant effects (World Health Organisation 2012). Respiratory protective devices are commonly used to mitigate worker exposure to many hazardous contaminants, especially in heavy industry such as mining and refining. Current standards to evaluate penetration through respirator filter media may not consider ultrafine particles due to the diameter of the challenge aerosol and the detection limit of the instrument (Eninger et al. 2008). Nor do they test penetration at flow rates representative of moderate to heavy work rates. Research is currently being undertaken at the University of Wollongong, Australia, to develop a method to measure penetration through respirator filter media using diesel emissions, rather than the standard challenge aerosol of NaCl, at flow rates consistent with moderate to heavy work rates. Methods: Emissions from a Detroit D706 LTE diesel engine were fed into an experimental chamber which was purpose built for the study. Penetration through a range of commonly used respirator filters in Australian workplaces was determined by particle count at diameters ranging from 5.6 - 560nm, using an Engine Emissions Particle Sizer (EEPS). Penetration was also measured by mass of Elemental Carbon, using NIOSH 5040. Flow rates were as designated in AS/NZS 1716 (Standards Australia International Ltd & Standards New Zealand 2012) and ISO DIS 16975 - 1.2 Work Rates 2 and 3 (ISO 2015), consistent with moderate to heavy work rates. Results and Conclusions: A method has been developed and validated and a pilot study completed. Initial findings indicate penetration exceeded standards specified limits for filtering efficiency for a number of filters for the size range <50 >nm, when measured as a function of particle c

Diesel engines have been a mainstay within many industries since the early 1900s. Exposure to diesel particulate matter (DPM) is a major issue in many industrial workplaces given the potential for serious health impacts to exposed workers; including the potential for lung cancer and adverse irritant and cardiovascular effects. Personal respiratory protective devices are an accepted safety measure to mitigate worker exposure against the potentially damaging health impacts of DPM. To be protective, they need to act as effective filters against carbon and other particulates. In Australia, the filtering efficiency of respiratory protective devices is determined by challenging test filter media with aerosolised sodium chloride to determine penetration at designated flow rates. The methodology outlined in AS/NZS1716 (Standards Australia International Ltd and Standards New Zealand 2012. Respiratory protective devices. Sydney/Wellington: SAI Global Limited/Standards New Zealand) does not account for the differences between characteristics of workplace contaminants like DPM and sodium chloride such as structure, composition, and particle size. This study examined filtering efficiency for three commonly used AS/NZS certified respirator filter models, challenging them with two types of diesel emissions; those from a diesel generator and a diesel engine. Penetration through the filter media of elemental carbon (EC), total carbon (TC), and total suspended particulate (TSP) was calculated. Results indicate that filtering efficiency assumed by P2 certification in Australia was achieved for two of the three respirator models for DPM generated using the small diesel generator, whilst when the larger diesel engine was used, filtering efficiency requirements were met for all three filter models. These results suggest that the testing methodology specified for certification of personal respiratory protective devices by Standards Australia may not ensure adequate protection for respirat

The objective of this study was to assess the impact of the filtration method (in situ vs. ex situ) on the dissolved/particulate partitioning of 12 elements in hydrothermal samples collected from the Lucky Strike vent field (Mid-Atlantic Ridge; MAR). To do so, dissolved ( <0.45 mu m) and particulate Mg, Li, Mn, U, V, As, Ba, Fe, Zn, Cd, Pb and Cu were measured using different techniques (HR-ICP-MS, ICP-AES and CCSA). Using in situ filtration as a baseline, we showed that ex situ filtration (on-board and on shore after freezing) resulted in an underestimation of the dissolved pool, which was counterbalanced by an overestimation of the particulate pool for almost all the elements studied. We also showed that on-board filtration was acceptable for the assessment of dissolved and particulate Mn, Mg, Li and U for which the measurement bias for the dissolved fraction did not exceed 3%. However, in situ filtration appeared necessary for the accurate assessment of the dissolved and particulate concentrations of V, As, Fe, Zn, Ba, Cd, Pb and Cu. In the case of Fe, on-board filtration underestimated the dissolved pool by up to 96%. Laboratory filtration (after freezing) resulted in a large bias in the dissolved and particulate concentrations, unambiguously discounting this filtration method for deep-sea chemical speciation studies. We discuss our results in light of the precipitation processes that can potentially affect the accuracy of ex situ filtration methods.

The objective of this study was to assess the impact of the filtration method (in situ vs. ex situ) on the dissolved/particulate partitioning of 12 elements in hydrothermal samples collected from the Lucky Strike vent field (Mid-Atlantic Ridge; MAR). To do so, dissolved ( <0.45 mu m) and particulate Mg, Li, Mn, U, V, As, Ba, Fe, Zn, Cd, Pb and Cu were measured using different techniques (HR-ICP-MS, ICP-AES and CCSA). Using in situ filtration as a baseline, we showed that ex situ filtration (on-board and on shore after freezing) resulted in an underestimation of the dissolved pool, which was counterbalanced by an overestimation of the particulate pool for almost all the elements studied. We also showed that on-board filtration was acceptable for the assessment of dissolved and particulate Mn, Mg, Li and U for which the measurement bias for the dissolved fraction did not exceed 3%. However, in situ filtration appeared necessary for the accurate assessment of the dissolved and particulate concentrations of V, As, Fe, Zn, Ba, Cd, Pb and Cu. In the case of Fe, on-board filtration underestimated the dissolved pool by up to 96%. Laboratory filtration (after freezing) resulted in a large bias in the dissolved and particulate concentrations, unambiguously discounting this filtration method for deep-sea chemical speciation studies. We discuss our results in light of the precipitation processes that can potentially affect the accuracy of ex situ filtration methods.

The objective of this study was to assess the impact of the filtration method (in situ vs. ex situ) on the dissolved/particulate partitioning of 12 elements in hydrothermal samples collected from the Lucky Strike vent field (Mid-Atlantic Ridge; MAR). To do so, dissolved ( <0.45 mu m) and particulate Mg, Li, Mn, U, V, As, Ba, Fe, Zn, Cd, Pb and Cu were measured using different techniques (HR-ICP-MS, ICP-AES and CCSA). Using in situ filtration as a baseline, we showed that ex situ filtration (on-board and on shore after freezing) resulted in an underestimation of the dissolved pool, which was counterbalanced by an overestimation of the particulate pool for almost all the elements studied. We also showed that on-board filtration was acceptable for the assessment of dissolved and particulate Mn, Mg, Li and U for which the measurement bias for the dissolved fraction did not exceed 3%. However, in situ filtration appeared necessary for the accurate assessment of the dissolved and particulate concentrations of V, As, Fe, Zn, Ba, Cd, Pb and Cu. In the case of Fe, on-board filtration underestimated the dissolved pool by up to 96%. Laboratory filtration (after freezing) resulted in a large bias in the dissolved and particulate concentrations, unambiguously discounting this filtration method for deep-sea chemical speciation studies. We discuss our results in light of the precipitation processes that can potentially affect the accuracy of ex situ filtration methods.

presented at the American Industrial Hygiene Conference & Exposition, May 30 - June 4 2015, Salt Lake City, Utah.

Fouling presents the most significant obstacle to optimal low-pressure membrane plant performance. The occurrence of fouling tends to decrease production rates (flux), increase chemical usage incurred during clean-in-place (CIP) process, increase energy costs, shorten membrane life and reduce recovery. Fouling may be of organic or inorganic nature, necessitating more frequent dual chemical cleaning procedures. Regardless of the nature of the foulants, particulate loading onto the membrane fiber surface has been identified as a common mechanism of deteriorating performance. Particulates and colloidal materials such as turbidity, natural organic material (NOM), algae and precipitated coagulant floc accumulate on the membrane surface and disrupt the laminar flow of water through the element. Particulates can either attach or adhere to the membrane surface through electrostatic attraction. One method of reducing this fouling mechanism is to employ controlled coagulation as a direct feed or coupled with a clarification step prior to membrane process. Coagulation can attract and retain naturally occurring particulates and colloidal materials via charge neutralization. Then, by controlling the charge of precipitated floc particulates to align with the surface charge of the membrane element, both types of fouling can be mitigated. This Paper summarizes two demonstrations featuring a pressure feed and a submerged vacuum ultrafiltration (UF) system.

of a presentation that was presented at 17th ISRP Conference, Prague, 21-25 September 2014.

presented at the 32nd Annual Conference & Exhibition of the Australian Institute of Occupational Hygienists Inc, 29 November - 3 December 2014, Melbourne, Australia.

presented at the 32nd Annual Conference & Exhibition of the Australian Institute of Occupational Hygienists Inc, 29 November - 3 December 2014, Melbourne, Australia

Compression ignition (CI) engine design is subject to many constraints which presents a multi-criteria optimisation problem that the engine researcher must solve. In particular, the modern CI engine must not only be efficient, but must also deliver low gaseous, particulate and life cycle greenhouse gas emissions so that its impact on urban air quality, human health, and global warming are minimised. Consequently, this study undertakes a multi-criteria analysis which seeks to identify alternative fuels, injection technologies and combustion strategies that could potentially satisfy these CI engine design constraints. Three datasets are analysed with the Preference Ranking Organization Method for Enrichment Evaluations and Geometrical Analysis for Interactive Aid (PROMETHEE-GAIA) algorithm to explore the impact of 1): an ethanol fumigation system, 2): alternative fuels (20 % biodiesel and synthetic diesel) and alternative injection technologies (mechanical direct injection and common rail injection), and 3): various biodiesel fuels made from 3 feedstocks (i.e. soy, tallow, and canola) tested at several blend percentages (20-100 %) on the resulting emissions and efficiency profile of the various test engines. The results show that moderate ethanol substitutions (~20 % by energy) at moderate load, high percentage soy blends (60-100 %), and alternative fuels (biodiesel and synthetic diesel) provide an efficiency and emissions profile that yields the most “preferred” solutions to this multi-criteria engine design problem. Further research is, however, required to reduce Reactive Oxygen Species (ROS) emissions with alternative fuels, and to deliver technologies that do not significantly reduce the median diameter of particle emissions.

Melt fragmentation, quenching and long term coolability in a deep pool of water under reactor vessel is employed as a severe accident (SA) mitigation strategy in several designs of light water reactors (LWR). Geometrical configuration of the debris bed is one of the factors which define if the decay heat can be removed from the debris bed by natural circulation. Boiling and two-phase flow inside the bed also serves as a source of mechanical energy which can reduce the height of the debris bed by so called “self-leveling” phenomenon. However, to be effective in providing a coolable geometrical configuration, self-leveling time scale has to be smaller than the time scale for drying out and onset of re-melting of the bed. This paper presents results of experimental and analytical studies concerning the self-leveling phenomenon. The goal of this work is to assess characteristic time scale of particulate debris spreading. In the experiments on the particulate debris spreading air injection at the bottom of the bed is used to simulate steam flow through the porous debris bed. A series of test have been carried out to study the influence of particles size and density, roughness of the spreading plate, gas flow rate etc. on particulate spreading. A semi-empirical model for predicting the spreading of particulate debris has been developed using experimental closures for debris mass flow rate as a function of local (i) angle of the bed and (ii) gas flux. The comparison between the model prediction and the experimental observations shows a good agreement., QC 20131216

Melt fragmentation, quenching and long term coolability in a deep pool of water under reactor vessel is employed as a severe accident (SA) mitigation strategy in several designs of light water reactors (LWR). Geometrical configuration of the debris bed is one of the factors which define if the decay heat can be removed from the debris bed by natural circulation. Boiling and two-phase flow inside the bed also serves as a source of mechanical energy which can reduce the height of the debris bed by so called “self-leveling” phenomenon. However, to be effective in providing a coolable geometrical configuration, self-leveling time scale has to be smaller than the time scale for drying out and onset of re-melting of the bed. This paper presents results of experimental and analytical studies concerning the self-leveling phenomenon. The goal of this work is to assess characteristic time scale of particulate debris spreading. In the experiments on the particulate debris spreading air injection at the bottom of the bed is used to simulate steam flow through the porous debris bed. A series of test have been carried out to study the influence of particles size and density, roughness of the spreading plate, gas flow rate etc. on particulate spreading. A semi-empirical model for predicting the spreading of particulate debris has been developed using experimental closures for debris mass flow rate as a function of local (i) angle of the bed and (ii) gas flux. The comparison between the model prediction and the experimental observations shows a good agreement., QC 20131216

Melt fragmentation, quenching and long term coolability in a deep pool of water under reactor vessel is employed as a severe accident (SA) mitigation strategy in several designs of light water reactors (LWR). Geometrical configuration of the debris bed is one of the factors which define if the decay heat can be removed from the debris bed by natural circulation. Boiling and two-phase flow inside the bed also serves as a source of mechanical energy which can reduce the height of the debris bed by so called “self-leveling” phenomenon. However, to be effective in providing a coolable geometrical configuration, self-leveling time scale has to be smaller than the time scale for drying out and onset of re-melting of the bed. This paper presents results of experimental and analytical studies concerning the self-leveling phenomenon. The goal of this work is to assess characteristic time scale of particulate debris spreading. In the experiments on the particulate debris spreading air injection at the bottom of the bed is used to simulate steam flow through the porous debris bed. A series of test have been carried out to study the influence of particles size and density, roughness of the spreading plate, gas flow rate etc. on particulate spreading. A semi-empirical model for predicting the spreading of particulate debris has been developed using experimental closures for debris mass flow rate as a function of local (i) angle of the bed and (ii) gas flux. The comparison between the model prediction and the experimental observations shows a good agreement., QC 20131216

The Water Framework Directives aims a reduction in concentration of hazardous substances in the marine environment. Consequently, there is a need to distinguish between anthropogenically influenced metal concentrations from natural background levels. To better achieve this goal in the Portuguese coast, dissolved and particulate trace metal (TM) concentrations along the Portuguese coast were determined in 46 sites distance 1–3 km from the shoreline. Dissolved values ranged within the following intervals: 0.01–0.89 nM for Cd, 0.01–3.37 nM for Co, 0.90–45.4 nM for Cu, 3.30–140 pM for Hg, 1.88–15.1 nM for Ni, 0.01–0.15 nM for Pb and 1.40–62.0 nM for Zn. Whereas Cd, Co, Cu, Ni and Zn were enhanced in the southern coast, while Pb values were higher in the central part of the western coast. Mercury concentrations showed punctual increases all along the coast. Values of trace metals in suspended particulate matter varied in a broad range: 36–2902 μmol g−1 for Al, 0.10–15.1 nmol g−1 for Cd, 1.50–165 nmol g−1 for Co, 50.0–990 nmol g−1 for Cu, 2.80–76.4 nmol g−1 for Hg, 22–1471 nmol g−1 for Ni, 10.0–347 nmol g−1 for Pb and 416–10,981 nmol g−1 for Zn. Higher values for Al, Ni and Co were found in the central part of the western coast. However, Cd, Cu, Pb and Zn increased their levels from the north coast towards the central and south areas. The variability of both dissolved and particulate metals appears to be mainly associated with oceanographic conditions and continental inputs at North and central areas of the coast, and in the south coast to geological features rather than to anthropogenic pressures. On the basis of these results, regional baseline concentrations are proposed for the three typologies in Portuguese coastal waters defined under the Water Framework Directive

An approach using trace elements in particulate matter (PM) to identify the geographic sources of atmospherically transported semivolatile organic contaminants (SOCs) was investigated. Daily samples of PM and SOCs were collected with high-volume air samplers from 16 January to 16 February 2009 at Temple Basin, a remote alpine site in New Zealand's Southern Alps. The most commonly detected pesticides were dieldrin, trans-chlordane, endosulfan I, and chlorpyrifos. Polycyclic aromatic hydrocarbons and polychlorinated biphenyls were also detected. For each sampling day, the relative contribution of PM from regional New Zealand versus long-range Australian sources was determined using trace element profiles and a binary mixing model. The PM approach indicated that endosulfan I, indeno[1,2,3-c,d]pyrene, and benzo[g,h,i]perylene found at Temple Basin were largely of Australian origin. Local wind observations indicated that the chlorpyrifos found at Temple Basin primarily came from the Canterbury Plains in New Zealand.

Generally, sigmoid curves are used to describe the growth of animals over their lifetime. However, because growth rates often differ over an animal's lifetime a single curve may not accurately capture the growth. Broken-stick models constrained to pass through a common point have been proposed to describe the different growth phases, but these are often unsatisfactory because essentially there are still two functions that describe the lifetime growth. To provide a single, converged model to age animals with disparate growth phases we developed a smoothly joining two-phase nonlinear function (SJ2P), tailored to provide a more accurate description of lifetime growth of the macropod, the Tasmanian pademelon Thylogale billardierii. The model consists of the Verhulst logistic function, which describes pouch-phase growth - joining smoothly to the Brody function, which describes post-pouch growth. Results from the model demonstrate that male pademelons grew faster and bigger than females. Our approach provides a practical means of ageing wild pademelons for life history studies but given the high variability of the data used to parametrise the second growth phase of the model, the accuracy of ageing of post-weaned animals is low: accuracy might be improved with collection of longitudinal growth data. This study provides a unique, first robust method that can be used to characterise growth over the lifespan of pademelons. The development of this method is relevant to collecting age-specific vital rates from commonly used wildlife management practices to provide crucial insights into the demographic behaviour of animal populations.

We applied a multiple linear regression model to understand the relationships of PM2.5 with meteorological variables in the contiguous US and from there to infer the sensitivity of PM2.5 to climate change. We used 2004–2008 PM2.5 observations from ~1000 sites (~200 sites for PM2.5 components) and compared to results from the GEOS-Chem chemical transport model (CTM). All data were deseasonalized to focus on synoptic-scale correlations. We find strong positive correlations of PM2.5 components with temperature in most of the US, except for nitrate in the Southeast where the correlation is negative. Relative humidity (RH) is generally positively correlated with sulfate and nitrate but negatively correlated with organic carbon. GEOS-Chem results indicate that most of the correlations of PM2.5 with temperature and RH do not arise from direct dependence but from covariation with synoptic transport. We applied principal component analysis and regression to identify the dominant meteorological modes controlling PM2.5 variability, and show that 20–40% of the observed PM2.5 day-to-day variability can be explained by a single dominant meteorological mode: cold frontal passages in the eastern US and maritime inflow in the West. These and other synoptic transport modes drive most of the overall correlations of PM2.5 with temperature and RH except in the Southeast. We show that interannual variability of PM2.5 in the US Midwest is strongly correlated with cyclone frequency as diagnosed from a spectral-autoregressive analysis of the dominant meteorological mode. An ensemble of five realizations of 1996–2050 climate change with the GISS general circulation model (GCM) using the same climate forcings shows inconsistent trends in cyclone frequency over the Midwest (including in sign), with a likely decrease in cyclone frequency implying an increase in PM2.5. Our results demonstrate the need for multiple GCM realizations (because of climate chaos) when diagnosing the effect of climate

An approach using trace elements in particulate matter (PM) to identify the geographic sources of atmospherically transported semivolatile organic contaminants (SOCs) was investigated. Daily samples of PM and SOCs were collected with high-volume air samplers from 16 January to 16 February 2009 at Temple Basin, a remote alpine site in New Zealand's Southern Alps. The most commonly detected pesticides were dieldrin, trans-chlordane, endosulfan I, and chlorpyrifos. Polycyclic aromatic hydrocarbons and polychlorinated biphenyls were also detected. For each sampling day, the relative contribution of PM from regional New Zealand versus long-range Australian sources was determined using trace element profiles and a binary mixing model. The PM approach indicated that endosulfan I, indeno[1,2,3-c,d]pyrene, and benzo[g,h,i]perylene found at Temple Basin were largely of Australian origin. Local wind observations indicated that the chlorpyrifos found at Temple Basin primarily came from the Canterbury Plains in New Zealand.

Generally, sigmoid curves are used to describe the growth of animals over their lifetime. However, because growth rates often differ over an animal's lifetime a single curve may not accurately capture the growth. Broken-stick models constrained to pass through a common point have been proposed to describe the different growth phases, but these are often unsatisfactory because essentially there are still two functions that describe the lifetime growth. To provide a single, converged model to age animals with disparate growth phases we developed a smoothly joining two-phase nonlinear function (SJ2P), tailored to provide a more accurate description of lifetime growth of the macropod, the Tasmanian pademelon Thylogale billardierii. The model consists of the Verhulst logistic function, which describes pouch-phase growth - joining smoothly to the Brody function, which describes post-pouch growth. Results from the model demonstrate that male pademelons grew faster and bigger than females. Our approach provides a practical means of ageing wild pademelons for life history studies but given the high variability of the data used to parametrise the second growth phase of the model, the accuracy of ageing of post-weaned animals is low: accuracy might be improved with collection of longitudinal growth data. This study provides a unique, first robust method that can be used to characterise growth over the lifespan of pademelons. The development of this method is relevant to collecting age-specific vital rates from commonly used wildlife management practices to provide crucial insights into the demographic behaviour of animal populations.