Search results for "Pollution"
showing 10 items of 2765 documents
Association between cooking fuels and mild cognitive impairment among older adults from six low- and middle-income countries
2022
AbstractThere is a small body of evidence suggesting that unclean cooking fuel use may be associated with cognitive decline. However, to date, no study has investigated the association between unclean cooking fuel and mild cognitive impairment (MCI). Thus, we investigated the association between cooking fuel type or ventilation type and MCI among adults aged ≥ 65 years using nationally representative datasets from six low- and middle-income countries. Cross-sectional, community-based data from the World Health Organization (WHO) Study on global Ageing and adult health (SAGE) were analyzed. MCI was defined using the National Institute on Aging-Alzheimer's Association criteria. Unclean cookin…
“Sweet” ionic liquid gels: materials for sweetening of fuels
2018
The search for new materials to be used in desulfurisation (sweetening) of fuels is one of the main topics of current research. In this paper, we explored the possibility of using supramolecular gels obtained from the gelation of ionic liquid binary mixtures. Indeed, some ionic liquids are generally known as efficient extraction phases for desulfurisation of fuels. In rare cases, one of their main drawbacks is their partial solubility in the fuel, leading to contamination. Then, their immobilisation due to the formation of a gelatinous network may be a challenge. Ionic liquid gels were obtained by mixing certain [NTf2]−-based ionic liquids (solvents) with the ones of gluconate-based ionic l…
Strecker reactions with hexacyanoferrates as non-toxic cyanide sources
2019
The Strecker reaction is the most widely applied three-component reaction. Although highly useful for the preparation of α-amino nitriles, α-amino acids, hydantoins and numerous related compounds, the need for the application of toxic sources of HCN limits its application in both academic and industrial settings. Here, we present a facile protocol for Strecker reactions using a mixture of potassium ferri- and ferrocyanides as a non-toxic substitute.
Hierarchical Beta zeolites as catalysts in a one-pot three-component cascade Prins–Friedel–Crafts reaction
2020
Hierarchical Beta zeolites obtained from concentrated reaction mixtures (H2O/Si = 2.5–7.0) in the presence of CTAB and their conventional and nanosponge analogues were investigated in a one-pot cascade environmentally friendly Prins–Friedel–Crafts reaction of butyraldehyde with 3-buten-1-ol and anisole under mild conditions (60 °C). The highest yields of the desired products with 4-aryltetrahydropyran structure were achieved when using hierarchical zeolites characterised by well-developed mesoporosity (facilitating the formation of bulky intermediates and products) and by an increased fraction of highly accessible (evaluated by TTBPy method) medium-strength Bronsted acid sites. Acid sites w…
Who's better at spotting? A comparison between aerial photography and observer-based methods to monitor floating marine litter and marine mega-fauna.
2020
Pollution by marine litter is raising major concerns due to its potential impact on marine biodiversity and, above all, on endangered mega-fauna species, such as cetaceans and sea turtles. The density and distribution of marine litter and mega-fauna have been traditionally monitored through observer-based methods, yet the advent of new technologies has introduced aerial photography as an alternative monitoring method. However, to integrate results produced by different monitoring techniques and consider the photographic method a viable alternative, this ‘new’ methodology must be validated. This study aims to compare observations obtained from the concurrent application of observer-based and…
Associations between air pollution and pediatric eczema, rhinoconjunctivitis and asthma: A meta-analysis of European birth cohorts
2020
Background: Uncertainly continues to exist regarding the role of air pollution on pediatric asthma and allergic conditions, especially as air pollution levels have started to decrease in recent decades. Objective: We examined associations of long-term air pollution levels at the home address with pediatric eczema, rhinoconjunctivitis and asthma prevalences in five birth cohorts (BIB, EDEN, GASPII, RHEA and INMA) from seven areas in five European countries. Methods: Current eczema, rhinoconjunctivitis and asthma were assessed in children aged four (N = 6527) and eight years (N = 2489). A multi-morbidity outcome (≥2 conditions versus none) was also defined. Individual outdoor levels of nitrog…
A Regional Geography Approach to Understanding the Environmental Changes as a Consequence of the COVID-19 Lockdown in Highly Populated Spanish Cities
2021
Spain has been highly impacted by the COVID-19 pandemic, which is reflected at different scales. From an economic point of view, lockdowns and the reduction of activities have damaged the country (e.g., complete lockdown from March 13 to June 21, 2020). However, it is not clear if the associated environmental impacts could be observed in 2020. Currently, studies on the effects of the lockdown (e.g., decrease in economic activities, transport and social communication) on specific parameters related to climate change, such as air temperature or air pollution, due to a drastic decrease in human activities are rare. They are focused on specific cities and short periods of time. Therefore, the m…
Simulated European stalagmite record and its relation to a quasi-decadal climate mode
2013
Abstract. A synthetic stalagmite record for the Bunker cave is constructed using a combined climate-stalagmite modeling approach. The power spectrum of the simulated speleothem calcite δ18O record has a pronounced peak at quasi-decadal time scale. Interestingly, mixing processes in the soil and karst above the cave represent a natural low-pass filter of the speleothem climate archive. We identify a quasi-decadal mode characterized by a "tripole pattern" of sea surface temperature affecting stalagmite δ18O values. This pattern, which is well-known in literature as the quasi-decadal mode in the North Atlantic, propagates eastwards and affects western European temperature surrounding the cave.…
Environmental and biological factors are joint drivers of mercury biomagnification in subarctic lake food webs along a climate and productivity gradi…
2021
Subarctic lakes are getting warmer and more productive due to the joint effects of climate change and intensive land-use practices (e.g. forest clear-cutting and peatland ditching), processes that potentially increase leaching of peat- and soil-stored mercury into lake ecosystems. We sampled biotic communities from primary producers (algae) to top consumers (piscivorous fish), in 19 subarctic lakes situated on a latitudinal (69.0-66.5 degrees N), climatic (+3.2 degrees C temperature and +30% precipitation from north to south) and catchment land-use (pristine to intensive forestry areas) gradient. We first tested how the joint effects of climate and productivity influence mercury biomagnific…
Anticipating the impact of pitfalls in kinetic biodegradation parameter estimation from substrate depletion curves of organic pollutants
2019
[EN] Accurate and reliable estimation of kinetic parameters of pollutant biodegradation processes is essential for environmental and health risk assessment. Common biodegradation models proposed in the literature, such as the nonlinear Monod equation and its simplified versions (e.g. Michaelis-Menten-like and first-order equations), are problematic in terms of accuracy of kinetic parameters due to the parameter correlation. However, a comparison between these models in terms of accuracy and reliability, related to data imprecision, has not been performed in the literature. This task is necessary, mainly because the model selection cannot be straightforward, as shown in this work. To facilit…