Aerobiologia最新文献

Exposure to wastewater treatment system (WWTS)-associated bioaerosols is not only linked with macro/field scale systems but also facilities which are operated in micro- and/or indoor environment such as university campus and research institutions. In this context, investigations on a laboratory-scale WWTS, adopting a sequential batch biofilm process and fed with synthetic municipal wastewater, were done in terms of its global treatment performance and characterization of emitted bioaerosols species. The microbial diversity of captured bioaerosols, collected through conventional particulate matter samplers, was identified on the basis of their metabolic properties using analytical profile index, biochemical tests, and other media specific growth patterns. Monitoring and analysis results of air quality in control and experimental period revealed that particulate emission from bioreactor increased the concentration of PM₁₀ and PM_2.5 up to 26.49 ± 4.18 µg/m³ and 12.84 ± 2.48 µg/m³ from an initial level of 17.26 ± 4.58 µg/m³ and 8.70 ± 1.84 µg/m³, respectively. Microscopic observations and staining characteristics revealed that cocci shape gram-negative and bacilli shape gram-positive bacteria dominated the bioaerosols with quantitative contribution as 70% and 9%, respectively. Based on the morphological and biochemical characterization, dominant isolated genera of opportunistic pathogenic bacteria in bioaerosols were identified as Escherichia coli, Bacillus cereus, Bacillus subtilis and Pseudomonas sp. with % dominance as 38.46, 13.46, 9.61 and 25, respectively. Overall, the findings of this study reiterate the concern of biological air pollution in research laboratories and represent an inevitable aspect for the validation of bioaerosol exposure in laboratory-scale WWTS workplaces.

Since research began in diatom ecology, scientists have focussed more on diatoms from aquatic habitats as opposed to aerial habitats. In this paper, we present the first dataset on diatoms from aerial habitats in the Indo-Burma hot spot. We have chosen the Blue Mountain region to collect tree mosses, an aerial habitat where diatoms thrive. We have addressed diatom composition and diversity in relation to altitude. Twenty-two moss samples were collected and 53 diatom taxa belonging to 21 genera were discovered and enumerated using light microscopy. The diatom flora of tree mosses is dominated by acidophilous genera Eunotia and Luticola, with both of the most abundant species Orthoseira roeseana and Luticola acidoclinata being euaerial and oligotraphentic diatoms. The samples from 1902-m altitude had the highest species diversity. Species richness was 8–22 diatom per sample, with an average of 14. The species accumulation curve shows that more diatom species will be discovered with additional sampling of aerial habitats in the Blue Mountain region.

This study investigates the use of pollen elastically scattered light images for species identification. The aim was to identify the best recognition algorithms for pollen classification based on the scattering images. A series of laboratory experiments with a Rapid-E device of Plair S.A. was conducted collecting scattering images and fluorescence spectra from pollen of 15 plant genera. The collected scattering data were supplied to 32 different setups of 8 computer vision models based on deep neural networks. The models were trained to classify the pollen types, and their performance was compared for the test sub-samples withheld from the training. Evaluation showed that most of the tested computer vision models convincingly outperform the basic convolutional neural network used in our previous studies: the accuracy gain was approaching 10% for best setups. The models of the Weakly Supervised Object Detection approach turned out to be the most accurate, but also slow. However, even the best setups still did not provide sufficient recognition accuracy barely reaching 65%–70% in the repeated tests. They also showed many false positives when applied to real-life time series collected by Rapid-E. Similar to the previous studies, fusion of the new scattering models with the fluorescence-based identification demonstrated almost 15% higher skills than either of the approaches alone reaching 77–83% of the overall classification accuracy.

From clinical point of view, knowledge of the pollen season and loads in the atmosphere of every community is important so as to guide on incidence and management of pollinosis. The aim of this work therefore is to evaluate the weekly constituents of the atmospheric pollen and fern spores of two communities in Lagos Nigeria and the relationship, if any, between the weekly aeroflora and hospital reported pollinosis cases. As part of efforts to contribute to the gathering of aerobiological data in Lagos State, a weekly gravimetric sampling of two locations (Ipaja and Ogba) in Lagos, Nigeria were undertaken from January 2018–December 2018 and the reported pollinosis cases (asthma and rhinitis) were collected from the surrounding hospitals. The samplers were placed on rigid platforms at 2 m above the ground level, the harvested residues were subjected to standard palynological procedure and twenty microlitres of each sample were studied microscopically. A total of 30 pollen taxa were identified with Amaranthaceae (544) dominating the palynomorphs at Ipaja and Elaeis guineensis (347) at Ogba. Using correlation (r = 0.1, p-value = 0.55 at Ipaja while r = 0.3, p-value = 0.33 at Ogba) and RDA test at p > 0.05, there is insignificant positive relationship between pollinosis cases and abundance of palynomorphs. However, at Ipaja, RDA indicated Poaceae and Elaeis guineensis as the possible drivers for asthma cases while Amaranthaceae and fungal spores were identified as weak drivers for catarrh. At Ogba, the loess curve and correlation test showed a significant positive relationship at p < 0.05 between the reported pollinosis cases and abundance of recovered palynomorph. Elaeis guineensis, Nephrolepis sp. and Dryopteris sp. seem to be the main drivers of asthma while Casuarina sp. and fungal spores perhaps drove catarrh. Dryopteris and Nephrolepis spores are firstly implicated as possible allergenic aeroconstituents in Nigeria in this work. The results from this work provide a background reference for the general public and hypersensitive individuals on the spatial distribution of pollen grains and fern spores in the study areas of Lagos as well as being a guide to the identification of culprit allergenic aeroconstituent.

Pollen grains of the anemophilous plants are the most important source of allergens in the atmosphere, triggering allergic diseases such as rhinitis and asthma in atopic individuals. Pollen grains in the atmosphere of Tétouan (NW of Morocco) were recorded during a 10 years/period (2008–2017) using a 7 day recording volumetric pollen trap by Burkard. Daily mean pollen concentrations of 10-day periods were summed and averaged over the study period to construct the pollen calendar. The average annual pollen integral (APIn) recorded during this period was 37,955 p*day/m³, belonging to 52 higher plant taxa (30 trees and/or shrubs and 22 herbaceous species). The maximum APIn (62,848 p*day/m³) was recorded in 2009 and the minimum (18,423 p*day/m³) in 2017. During the study period, the main pollen was registered from February to June (89%), with the highest daily mean pollen concentrations recorded in March (26.38%) and February (21.13%). The timing, intensity and length of the pollen seasons varied according to the taxa. The pollen calendar of Tétouan atmosphere reflects a great pollen diversity (37 pollen types), Pollen omnipresence throughout the year, long pollination periods and typically Mediterranean taxa: Cupressaceae, Olea, Platanus and Quercus. Some trees and herbaceous plants perform their anthesis in winter: Cupressaceae, Fraxinus, Populus, Pinus, Mercurialis and Parietaria. Some of them extend their pollen season until spring at the same time as other types of pollen appear typical of spring. Morus and Pistacia have a short pollen season, while Cannabis sativa, Amaranthaceae, Olea, Parietaria, Plantago, Poaceae, Quercus, Rumex and U. membranacea are characterized by prolonged pollen season. The pollen spectrum of Tétouan is differentiated by Cannabis pollen, and a longer and more intense pollination period than that detected in other Mediterranean regions. Based on these results, pollen calendar of Tétouan provides interesting and useful information to aerobiologists as well as professionals working in fields such as allergy and public health.

Alternaria is a pathogenic and allergenic fungus affecting 400 plant species and 334 million people globally. This study aimed at assessing the diversity of Alternaria species in airborne samples collected from closely located (7 km apart) and heterogeneous sites (rural, urban and unmanaged grassland) in Worcester and Lakeside, the UK. A secondary objective was to examine how the ITS1 subregion varies from ITS2 in Alternaria species diversity and composition. Airborne spores were collected using Burkard 7-day and multi-vial Cyclone samplers for the period 5 July 2016–9 October 2019. Air samples from the Cyclone were amplified using the ITS1and ITS2 subregions and sequenced using Illumina MiSeq platform whereas those from the Burkard sampler were identified and quantified using optical microscopy. Optical microscopy and eDNA revealed a high abundance of Alternaria in the rural, urban and unmanaged sites. ITS1 and ITS2 detected five and seven different Alternaria species at the three sampling sites, respectively. A. dactylidicola, A. metachromatica and A. infectoria were the most abundant. The rural, urban and unmanaged grassland sites had similar diversity (PERMANOVA) of the species due to similarity in land use and proximity of the sites. Overall, the study showed that heterogeneous and neighbouring sites with similar land uses can have similar Alternaria species. It also demonstrated that an eDNA approach can complement the classical optical microscopy method in providing more precise information on fungal species diversity in an environment for targeted management. Similar studies can be replicated for other allergenic and pathogenic fungi.

Abundance and diversity of airborne pollen are important to human health and biodiversity. The UK operational network collects airborne pollen from 8 flowering trees, grasses and three weeds using Hirst traps and microscopic identification from urban areas. Knowledge of total pollen diversity and differences between rural and urban zones is limited. We collect environmental DNA (eDNA) from air during summer and autumn over 3 years with mini cyclones from one urban and one rural site. Data are analysed using next generation sequencing and metabarcoding. We find the most common genus, Urtica (57%), is also identified by the national network. The grasses Lolium (10%), Agrostis (2%) and Holcus (1%) are in the national network grouped at family level, while Brassica (2%), Chenopodium (1%), Impatiens (2%), Plantago (4%) and Tilia (7%) are not part of the UK operational network. DNA from 138 genera was identified, where 2% of the sample could not be associated with specific genera. 40% of the sample was classified better using eDNA methods at the genus level, than by optical methods. We calculate Bray–Curtis dissimilarity for the rural and urban zones and find a systematic difference in biodiversity. Overall, this shows airborne DNA reveals more information than methods based on morphological differences. The results also suggest data from sites located in large urban areas will be less representative for less populated rural areas. This presents a dilemma in balancing a network and the associated costs delivering health relevant information to the most populated areas vs. a nation-wide approach.

The goal of this study is to determine if the annual pollen integral (APIn) for the top tree allergens in the City of Albuquerque is correlated with meteorological variables. This analysis would be the first of its kind for this area. We used 17 consecutive years from 2004 to 2020 and data collected by the city of Albuquerque using a Spore Trap (Burkard) volumetric air sampler in a location designed to represent a typical desert environment. The pollen studied include Juniper, Elm, Ash, Cottonwood, and Mulberry. We found a negative linear correlation with early summer temperatures of the previous year and APIn for Elm, Cottonwood, and Mulberry, and early fall temperatures for Juniper. Linear regression models developed for Elm, Cottonwood, and Mulberry used the monthly mean maximum temperature for the month of June of the prior year as the independent variable to yield a R squared statistic (R²) of 0.88, 0.91 and 0.78, respectively. For Juniper, the average monthly mean minimum temperature for the previous September and October served as the independent variable and yielded the R² value of 0.80. We also observed a positive trend for the annual maximum temperature over time and a negative trend for the total APIn. Summers in New Mexico are hot and dry, and they may be getting hotter and drier because of climate change. Our analysis predicts that climate change in this area may lead to reduced allergies if temperatures continue to increase and if precipitation patterns remain the same.

This note provides a generic method for handling falsely identified particles (false positive detections) in automatic pollen monitoring systems. The benefits of the method are illustrated using data from two different automatic pollen monitoring devices (Swisens Poleno and Plair Rapid-E) in comparison to reference Hirst-type pollen measurements. Neither climatological nor phenological information are introduced to filter out false positive detections: the method is based only on the measurements.