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The lockdown implemented to tackle the spread of the COVID-19 pandemic had a positive impact on air quality. Globally, studies have shown that air pollutant levels decreased temporally during the restriction measures. In this study, we evaluated the impact of COVID-19 restrictions on the air quality of Western Macedonia, Greece, using the concentrations of PM2.5 and PM10 along with meteorological data from the Air Quality Monitoring Stations (AQMS) operated by the Lignite Center of Western Macedonia. In Western Macedonia, previous studies have identified a general reduction in air pollutant levels during the last decade due to the coal phase-out plan for power generation. During the lockdown, the levels of PM2.5 and PM10 decreased further. The reduced emissions from the local mining activities and lignite-fired power plant electricity generation, as well as the weather conditions, seem to contribute to improving air quality.

This work presents information regarding PM10, PM2.5, Polycyclic Aromatic Hydrocarbons (PAHs), and trace elements that were obtained from two sampling stations, located in the region of Western Macedonia (North-Western Greece), over the course of a 12-month period. Τhe first sampling station was located near the village of Pontokomi (Station 1) and the second (Station 2) in the rural area of Petrana (Fig 1). Specifically, for each location, daily particulate samples PM10 (total 58 samples) and PM2.5 (total 64 samples) were collected. Moreover, and again for each location, 50 samples (22 PM10 and 28 PM2.5) were further analyzed for the determination of 15 (PAHs) and 72 samples (36 PM10 and 36 PM2.5) were further analyzed for the determination of a total of 17 trace elements. Thus, a total of approximately 10 samples per month was obtained from each sampling station (122 samples per sampling station over the course of 12 months). The samples were collected using two low volume samplers, LVS 3.1 and PNS16T-3.1 (Comde-Derenda GmbH). Trace elements were trapped using 47 mm glass fiber filters and were recovered using microwave extraction; for their determination, the graphite furnace atomic absorption spectrometry (GFAAS) technique was utilized. The PAHs were trapped with 47 mm quartz fiber filters and were analyzed using dichloromethane extraction followed by gas chromatography–mass spectrometry.This region of Western Macedonia has historically been the center of electricity production in Greece. Lignite is mined in open-cast mines and used as feed in a number of thermal power plants. At its peak, which was in the 1990’s, the areas produced close to 70% of electricity in Greece. Since then, electricity production (and related activities) are in decline as, due to Greece's EU commitments, the region has entered a transition, post-lignite process.

This manuscript presents the concentrations of inhalable suspended particles with diameter less than 10 µm (PM10) in the region of west Macedonia, Greece, from a total of nine locations, from 2010 to 2020. This region, the only landlocked region in the country, has acted as the pillar of electricity production in Greece since 1960, utilizing lignite in thermal power stations, which was open mined in the locality. However, following Greece's international commitments for climate action, the region has entered a transition, post-lignite process.Particulate matter concentrations in the region are monitored by the Public Power Corporation (PPC), which operates the mines and thermal power stations, using Grimm Aerosol Technik analyzer, model EDM180.

In this work we use Artificial Intelligence (AI) for the detection of faults in air quality measurements. This is crucial in large air quality monitoring networks in particular were fault detection can be a complex and time consuming process. The proposed methodology encompasses several essential steps in anomaly detection. Data preprocessing ensures the quality and relevance of the data by applying techniques like data cleaning, outlier removal, and feature selection. The Isolation Forest model is trained using the pre-processed data, and appropriate hyperparameters are determined through cross-validation. Anomaly detection is performed using the trained model, allowing the identification of abnormal events or instances. The visualization of anomalies provides a clear representation of abnormal patterns, facilitating the interpretation and understanding of air quality data. The proposed methodology can help environmental agencies, researchers, and policymakers in identifying abnormal air quality events, enhancing the accuracy of monitoring systems, and facilitating timely interventions. This methodology can be applied to other industries also, to improve operations and reduce risk.

Air quality is important for the protection of human health, the environment and our cultural heritage and it is an issue that will acquire increased significance in the future due to the adverse effects of climate change. Thus, it is important to not simply monitor air quality, but to make information immediately available to those responsible for monitoring the networks, to policy/decision makers, but also to the general population. Moreover, the development of information technologies over the last couple of decades has allowed the proliferation of real-time pollution monitoring. The work presented herein concerns the development of an effective way of monitoring environmental parameters using dedicated software. It offers a complete suite of applications that support environmental data collection management and reporting for air quality and associated meteorology. It combines modern technologies for the proper monitoring of air quality networks, which can consist of one or more measuring stations. Innovatively, it also focuses on how to effectively present the relevant information, utilizing modern technologies, such as cloud and mobile applications, to network engineers, policy/decision managers, and to the general public at large. It also has the capability of notifying appropriate personnel in the event of failures, overruns or abnormal values. The system, in its current configuration, handles information from six networks that include over 55 air pollution monitoring stations that are located throughout Greece. This practical application has shown that the system can achieve high data availability rates, even higher than 99% during the year.

Western Macedonia, located in North-western Greece, is largely dominated by lignite mining and lignite-fired power plants, which are a significant part of the country’s economy. However, the electricity generation and the related activities are among the greatest sources of air pollutants. In this study, we focus on the air quality of Western Macedonia based on measurements of Particulate Matter (PM2.5 and PM10) over a 12-year period (from 2010 to 2021) and a sampling of PM-bound trace elements over the course of 12 months (from December 2017 to November 2018). The analysis revealed an overall decrease of PM2.5 and PM10 concentrations over the study period. In general, the concentrations of PM exhibited seasonality patterns associated with the weather conditions and the local sources of air pollutants. These major sources of air pollution are the lignite mining processes, the emissions from the lignite-fired power plants, and the anthropogenic emissions from the biomass burning and heating systems. In addition, the analysis of the PM-bound trace elements revealed some differences; the elemental profiles of both PM2.5 and PM10 were quite similar, while the most abundant elements (Ca and Si) indicate that the main emission sources were related with the mining activities and the coal combustion.

Windows are responsible for significant amounts of energy loss through typical building envelopes. There have been multiple studies on heat loss through the glazing unit and frame system. This study presents an experimental investigation of a window unit and focuses specifically on the conductance between the structural elements and the frame system of a conventional house in the city of Xanthi, northern Greece. It is obvious that even a perfect window system cannot reduce heat transfer between the base of the frame and the upper surface of the floor. The experimental and simulation procedure of this project includes the installation of an insulating layer in front of the window unit for a variety of frames (solid wood, aluminum, PVC, etc.) at different distances. The main objective of this paper is to determine how effective an insulating barrier can be in respect to different types of frame, glazing, and weather conditions for the control of heat loss. Through the application of this technique, in combination with an appropriate insulating frame and window unit, designers can control the temperature inside the room at close proximity to the windows, in order to contribute to energy saving, aiming towards a building with zero energy demand.

This study focuses on the post-larval development of Hippolyte sapphica morphotypes, during the late reproductive period. The species is endemic to Central/Eastern Mediterranean and displays morphοtype A with a well-developed rostrum and morphotype B with a short, juvenile-like one. Our results partly confirm the previous findings on the rostral dimorphism, while also providing new, detailed results obtained on pre-ovigerous specimens. In the A-males, two distinct sub-populations were discriminated: the main group with a fast rostral development, and a small one, with a slower rostral growth rate. The rostral growth in A-females was significantly attenuated, without identifiable subgroups. No difference was detected in the negative allometric rostral growth of B-specimens in both sexes. The relative growth of the appendix interna was nearly the same in females of both morphotypes, whereas the growth rate of the appendix masculina was significantly higher in A-males with fast rostral development, attenuated in B-males, and finally being the lowest in A-males with slowly developing rostral. Even within the A-males’ subgroup, a significant partial correlation was detected between the relative growth of the rostrum and that of the appendix masculina. The relationship between growth of the rostrum and sexual appendages raises the question about underlying molecular mechanisms. [ABSTRACT FROM AUTHOR]