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A theoretical–experimental approach is proposed to convert the photoluminescence spectra of colloidal perovskite quantum dot ensembles into accurate estimates for their intrinsic particle size distribution functions. Two main problems were addressed and properly correlated: the size dependence of the first excitonic transition in a single cube-shaped quantum dot and the inhomogeneous broadening of the fluorescence line shape due to the size nonuniformity of the chemically prepared quantum dot suspension in addition to the single-dot homogeneous broadening. By applying the reported methodology to CsPbBr3 quantum dot samples belonging to the strong and intermediate confinement regimes, the calculated size distributions exhibited close agreement with those obtained from transmission electron microscopy, with precise estimates for the average particle size and standard deviation. Specifically for strongly confined ultrasmall CsPbBr3 quantum dots, the presented spectroscopic model for size distribution computation is based on a new analytical expression for the size-dependent bandgap, which was developed within the framework of the finite-depth square-well effective mass approximation accounting for band nonparabolicity effects. Such a quantum mechanical approach correctly predicts the expected transition to the intermediate confinement regime in sufficiently large quantum dots, which are traditionally described by the well-known bandgap equation in the infinite potential barrier limit with a spatially correlated electron–hole wavefunction and nonparabolic carrier effective masses. The proposed calculation scheme originates from general theoretical considerations so that it can be readily adapted to semiconductor quantum dots of many other systems, from all inorganic metal halides to hybrid perovskite materials, regardless of the adopted chemical synthesis route. [ABSTRACT FROM AUTHOR]

In mountainous regions, the atmospheric dispersion of air pollutants is limited by complex terrain morphology. Trentino (a province located in the Italian Alps) is characterized by a high population density, highly developed agriculture and farming, and the presence of civil and industrial activities, whose emissions tend to be trapped inside the valleys. These conditions translate into exposure levels that are potentially higher than other geographical contexts (e.g., flat or coastal regions). The academic research carried out in Trentino since 2005 has produced a series of publications on topics related to the risk for health derived from waste management and other activities. These publications has focused on: 1) the evaluation of the emissions of organic pollutants from the waste sector; 2) the monitoring of persistent organic pollutants (POPs) in various environmental matrices; 3) a methodology to carry out a comprehensive health risk assessment considering all the relevant exposure routes in an area; 4) the role of the local diet in the exposure of a population to POPs; 5) methodologies to define new regulatory limit values for dioxin and hexavalent chromium; and 6) the role of dispersion modeling in assessing the exposure to air pollutants. The present paper will review these publications and provide a reference document to evaluate new project proposals that require a health risk assessment and facilitate the work of proponents, clarifying the requirements of a health risk assessment. The paper will refer to waste gasification, but the considerations expressed in this paper may apply to other activities.

The Environmental Monitoring Plan (EMP) and the Monitoring and Control Plan (MCP) are key documents required respectively in Environmental Impact Assessment (EIA) procedures and in the Integrated Environmental Authorization (IEA) for activities subjected to this procedure. Both documents aim at preventing impacts on the environment and human health and/or quickly taking actions if anomalous levels of pollutants are found in the environment. Trentino is an Italian region located in the Alps characterized by high population density in its valleys, complex terrain and, thus, a low level of dispersion of the atmospheric pollutants. The research carried out in Trentino in the last two decades has allowed identifying innovative monitoring approaches to point out issues that conventional methodologies could not detect. The present paper provides the key elements of an EMP that must be included in the EIA of a waste gasification plant. The paper proposes unconventional monitoring campaigns to guarantee a more efficient control of the areas influenced by the plant before, during and after its construction. The paper also discusses key aspects of an MCP for plants that are subjected to IEA. The final aim is to make this paper a reference document to 1) evaluate new projects of waste combustion plants, 2) suggest alternative monitoring methodologies to investigate the role of specific pollutants in peculiar contexts, and 3) prescribe a specific surveillance plan in the case of a plant that is subjected to IEA. Considerations on differences with conventional plants were also included.

Quantum dots (QDs) have attracted much attention and exhibit many attractive properties, including high absorption coefficient, adjustable bandgap, high brightness, long-term stability, and size-dependent emission. It is known that to obtain high-quality luminescent properties (i.e. emission color, color purity, quantum yield, and stability), the synthesis parameters must be precisely controlled. In this work, we have constructed a database with CdTe aqueous synthesis parameters and spectroscopic results and applied machine learning algorithms to better understand the influence of the main synthesis parameters of CdTe QDs on their final emission properties. A strong dependence of the final emission wavelength with the reaction time and surface ligands and precursors concentrations was demonstrated. These parameters adjusted synchronously were shown to be very useful for provide ideal synthesis conditions for the preparation of CdTe QDs with desirable emission wavelengths. Moreover, applying the algorithms correctly allows for obtaining information and insights into the growth kinetics of QDs under different synthetic conditions. [ABSTRACT FROM AUTHOR]

In the last decade, due to prolonged and persisting drought conditions, California initially restricted water for outdoor landscape irrigation, and subsequently offered turf removal rebates to homeowners. Nevertheless, the effects of turf removal on land surface temperature (LST) in the region have not been investigated. Temperature differences between artificial and natural turf were assessed over time across four counties in Southern California using MODIS/ASTER airborne simulator (MASTER) with a spatial resolution of 5–50 m. Moreover, airborne thermal imagery (submeter spatial resolution) was acquired over selected areas of the city of Riverside, CA, during the summers of 2018 and 2019, including neighborhoods with different income levels, and temperatures for natural turf, artificial turf, and xeriscape were recorded. Environmental and socioeconomic data were compared to the LST in different neighborhoods. Results showed that the LST difference between artificial and natural turf increases in Southern California moving from coastal region to inland. Airborne thermal imagery in Riverside confirmed that University of California artificial turf fields are irrigated during the summer to allow athletes to use the pitch. No correlation between socioeconomic factors and LST of turf and artificial turf fields (and paired differences) was found. On a city scale, natural turf lawns were consistently cooler than xeriscape and artificial turf lawns, closely mirroring mean air temperature. Socioeconomic factors do not describe LST in residential lawns, as warmest and coolest lawns regardless of vegetation are found evenly distributed among different income neighborhoods. Turfgrass removal for water conservation may have unforeseen environmental side effects. Core Ideas: Temperature difference between natural and artificial turfgrass increases in inland California.Natural turfgrass lawns are consistently cooler than artificial turfgrass and xeriscape lawns.Socioeconomic factors do not predict residential lawns land surface temperature in Southern California. [ABSTRACT FROM AUTHOR]

Surfactants are commonly employed in sand‐based turfgrass systems to address soil water repellency, which often results in the formation of preferential flow channels leading to non‐uniform wetting patterns. While the influence of soil moisture on nutrient dynamics is well documented, the potential of surfactants to improve N uptake remains poorly understood. A 2‐year study was conducted on 'Celebration' bermudagrass [Cynodon dactylon (L.)] fairway to better understand the interaction between fertility programs (296 or 586 kg N ha−1 year−1 from ammonium sulfate and 564 kg N ha−1 year−1 primarily from a controlled‐release N fertilizer) and surfactant rate and frequency (3.2 L ha−1 every 14 or 28 days, or at 6.4 L ha−1 every 28 days) on turfgrass performance, leaf N content, and soil moisture. Overall, no significant interaction was observed between surfactant treatment and fertility program. During the dry season (November to May), fertility programs influenced turfgrass performance parameters with higher N rates consistently leading to improvements in visual quality, normalized difference vegetation index, percent green cover, and dark green color index; however, no differences were observed during the rainy season (June to October). Surfactants showed no effect on turfgrass performance but led to minimal increase in leaf N content from 3.72% to 3.85%. All surfactant treatments reduced water drop penetration time at 0 cm. Moreover, surfactant treatments applied every 28 days regardless of the rate exhibited a higher volumetric water content compared to those applied every 14 days. Surfactant applications might not be an economically feasible strategy to improve leaf N content in South Florida well‐watered bermudagrass fairways. Core Ideas: Surfactant applied at half rate had the same effect as full rate on soil moisture and water penetration.Surfactant applications might not be necessary to improve leaf N content in South Florida fairways.Higher N rates sustained bermudagrass quality over winter.Leaf N content within optimal ranges did not always translate to sufficient optimal turfgrass quality. [ABSTRACT FROM AUTHOR]

Chronic Obstructive Pulmonary Disease (COPD) and lung cancer are strictly related. To date, it is unknown if COPD-associated cancers are different from the tumors of non-COPD patients. The main goal of the study was to compare the morphological/molecular profiles of lung adenocarcinoma (LUAD) samples of COPD, non-COPD/smokers and non-COPD/non-smokers, and to investigate if a genetic instability also characterized non-pathological areas. This study included 110 patients undergoing surgery for a LUAD, divided into three groups: COPD/smoker LUAD (38), non-COPD/smoker LUAD (54) and non-COPD/non-smoker LUAD (18). The tissue samples were systemically evaluated by pathologists and analyzed using a 30-gene Next Generation Sequencing (NGS) panel. In a subset of patients, tissues taken far from the neoplasia were also included. The non-COPD/smoker LUAD were characterized by a higher proliferative index (p = 0.001), while the non-COPD/non-smoker LUAD showed higher percentages of lepidic pattern (p = 0.008), lower necrosis, higher fibrosis, and a significantly lower mutation rate in the KRAS and PIK3CA genes. Interestingly, the same gene mutations were found in pathological and normal areas exclusively in the COPD/smokers and non-COPD/smokers. COPD/smoker LUAD seem to be similar to non-COPD/smoker LUAD, particularly for the genetic background. A less aggressive cancer phenotype was confirmed in non-COPD/non-smokers. The genetic alterations detected in normal lungs from smokers with and without COPD reinforce the importance of screening to detect early neoplastic lesions. [ABSTRACT FROM AUTHOR]