Oxidation capacity changes in the atmosphere of large urban areas in Europe: Modelling and experimental campaigns in atmospheric simulation chambers.

Air pollution is a major concern for human health and the environment. Consequently, environmental standards have become stricter to improve air quality. Thanks to this, the ambient levels of O3 precursors such as VOCs and NOX have decreased. However, O3 levels in Europe, especially during winter, have increased, potentially impacting on atmospheric oxidation capacity and the associated chemistry of tropospheric oxidants. In this work, we focus on recent changes in the oxidation capacity of urban atmospheres. The study is conducted with the results of the CMAQ modelling system with a regional resolution with 12 × 12 km2 across the entire European continent for the winter (January) and summer (July) of 2007 and 2015. The 2015 meteorological data is used for both years to emphasise emission changes during the studied period. We scrutinise the changes in ambient concentration levels of the main tropospheric oxidants (O3 and HOX radicals) in five representative cities, Valencia, Madrid, Milan, Berlin, and The Hague. The enhanced O3 formation in winter seems to be due to the low VOC/NOX ratio, while the opposite trend in summer may be related to a relatively high ratio. Additionally, photooxidation experiments are carried out in the EUPHORE chambers to study the effect of changes in NOX concentration and NO/NO2 ratio on the variation of the given oxidants at constant VOCs concentrations. For the baseline experiments, two scenarios are selected based on the model results of 2015: two representative winter and summer days of low and high pollution in Berlin and Madrid, respectively. The role of VOC/NOX and NO/NO2 ratios on atmospheric reactivity is discussed. As a result, it is first suggested that further decreases in ambient NOX levels are required to reduce ambient O3 levels. Moreover, additional factors should be considered when designing local-specific emission abatement strategies.

Will recent world events shift policy-makers' focus from sustainable agriculture to intensive and competitive agriculture?

The events of recent years (pandemic and conflict in the European area) have led to a rethink of traditional policies on trade and support for domestic production. The concept of national "self-sufficiency" is being consolidated to the detriment of globalization and the possibility of buying raw materials on the world market at the lowest price. European agriculture, affected by the Common Agricultural Policy (CAP) review for the 2023/2027 programming period, is not exempt from this process. Therefore, the construction of National Strategic Plans may partly dampen the drive towards sustainability undertaken with the Green Deal and related strategies (from Farm to Fork, Biodiversity 2030, and Circular Economic) up to the 2030 Agenda Goals because producers are demanding greater freedom in production intensification. The research, conducted in a traditionally agricultural area in Italy, shows that competitive and sustainable agriculture can coexist thanks to entrepreneurial choices based on values and interest in the territory. Despite the difficulties arising from the changing conditions of the international scenario, which have led to an increase in production costs and a contraction of market opportunities, agriculture has become resilient thanks to sound agronomic practices and the sustainability of the process. Therefore, a model of agriculture more closely linked to the territory's characteristics is proposed.

Risk management options to contrast the introduction of citrus fruit bacterial canker through ornamental Rutaceae in the Mediterranean Basin: An Italian case study.

Citrus bacterial canker (CBC) is a known disease caused by Xanthomonas citri subsp citri, which affects many species and varieties of Rutaceae. It causes evident damage on the epigeal parts of plant (leaves and branches) and, in particular, on the fruits, causing their fall and/or deterioration, making them unsuitable for sale. EPPO has signaled its presence in many Asian countries and in the Middle East, in South and Central America and in some regions of the African continent, but not yet in Europe. There are several possible ways of introducing this pathogen into the Mediterranean Basin and, among these, there is the trade of plant material for propagation and planting and the flow of tourism between the risk areas and the Mediterranean countries. This research demonstrates how the risk of invasion through ornamental Rutaceae is evident and identifies - in a participatory way through the involvement of stakeholders - some possible tools of phytosanitary protection. The methodological approach, with multi-criteria analysis, recognizes the interest in forms of protection represented by voluntary certification tools, rather than the introduction of new taxation that can finance the protection system.

Trends in stabilisation of Criegee intermediates from alkene ozonolysis.

Criegee Intermediates (CI), formed in the ozonolysis of alkenes, play a central role in tropospheric chemistry as an important source of radicals, with stabilised CI (SCI) able to participate in bimolecular reactions, affecting climate through the formation of inorganic and organic aerosol. However, total SCI yields have only been determined for a few alkene systems, while speciated SCI yields from asymmetrical alkenes are almost entirely unknown. Here we report for the first time a systematic experimental exploration of the stabilisation of CH2OO and (CH3)2COO CI, formed from ten alkene-ozone systems with a range of different sizes and structures, under atmospherically relevant conditions in the EUPHORE chamber. Experiments in the presence of excess SO2 (an SCI scavenger) determined total SCI yields from each alkene-ozone system. Comparison of primary carbonyl yields in the presence/absence of SO2 determined the stabilisation fraction of a given CI. The results show that the stabilisation of a given CI increases as the size of the carbonyl co-product increases. This is interpreted in terms of the nascent population of CI formed following decomposition of the primary ozonide (POZ) having a lower mean energy distribution when formed with a larger carbonyl co-product, as more of the energy from the POZ is taken by the carbonyl. These findings have significant implications for atmospheric modelling of alkene ozonolysis. Higher stabilisation of small CI formed from large alkenes is expected to lead to lower radical yields from CI decomposition, and higher SCI concentrations, increasing the importance of SCI bimolecular reactions.

Taenia solium glutathione transferase fraction activates macrophages and favors the development of Th1-type response.

Glutathione (GSH) transferase (GST) is an essential enzyme in cestodes for the detoxification of xenobiotics. In Taenia solium, two GSTs (Ts25GST and Ts26GST kDa) were isolated as a fraction (SGSTF) by GSH-Sepharose-4B. Both are located on the tegument. Immunization assays with SGSTF reduced up to 90% of the parasitic load in a murine model of cysticercosis. It prompted us to investigate how SGSTF induces this protective immune response. To test it, we exposed peritoneal macrophages to SGSTF for 24 h; such exposure favored the production of IL-12, TNF, and IL-10 as well as the expression of nitric oxide synthase 2 inducible (Nos2) and CD86, but did not induce the expression of chitinase-like 3 (Chil3). Confocal microscopy showed that the macrophages internalize the SGSTF which co-localized after 1 h with MHC-II in their plasma membranes. Macrophages exposed to SGSTF and co-cultured with anti-CD3 pre-activated T CD4+ cells, enhanced the proliferation of CD4+ cells, induced high interferon-γ (IFN-γ) secretion, and elevated the expression of CD25 and CD69, molecules associated with cell activation. Similar assay using T CD4+ cells from DO11.10 mice and ovalbumin (OVA) peptide+SGSTF as stimuli, showed enhanced cell proliferation and OVA-specific IFN-γ secretion. These data are in-line with those indicating that the P1, P5, and P6 peptides of Schistosoma japonicum 28GST highly promote T-cell proliferation and Th1 response in vitro We found that such peptides are also present on Ts25GST and Ts26GST. It suggests that SGSTF activates peritoneal macrophages to a classically activated-like phenotype, and that these macrophages induce the differentiation of T CD4+ cells toward a Th1-type response.

Atmospheric Oxidation of a Thiocarbamate Herbicide Used in Winter Cereals.

The gas-phase atmospheric degradation of prosulfocarb (a widely used thiocarbamate herbicide in winter cereals) at different NOx concentrations was investigated at the large outdoor European PHOtoREactor (EUPHORE) in Valencia, Spain. Photolysis under sunlight conditions and reaction with ozone were shown as unimportant. The rate constant for the reaction of prosulfocarb with OH radicals was determined as k = (2.9 ± 0.5) × 10-11 cm3 molecule-1 s-1 at 288 ± 10 K and atmospheric pressure by a conventional relative rate method. Significant ozone and aerosol formation was observed following the reaction of prosulfocarb with OH radicals, and the main detected carbon-containing gas-phase products were benzaldehyde, S-benzyl formyl(propyl)carbamothioate, and S-benzyl propanoyl(propyl)carbamothioate.

Risk assessment of airborne pesticides in a Mediterranean region of Spain.

A risk assessment strategy based on the quantitative target analysis and semi-quantitative retrospective screening determination of pesticides in PM10 has been developed. The proposed methodology was applied to 345 real samples from nine stations of a Mediterranean area in Spain, and the risk was assessed for adult, children and infants. Forty pesticides were detected with average concentrations ranging from 8 to 30,000pgm-3. Each station showed its specific pesticide profile, which is linked to the different types of crops around each station. For adults, children and infants the estimated chronic inhalation risk, expressed as Hazard Quotient (HQ), was <1 for all pesticides. The cumulative exposure for organophosphates, neonicotinoids, benzimidazoles, carbamates, micro-organism and triazoles pesticides (HI, Hazard Index) were <1 for the three groups of populations assessed. For infants, the cancer risk estimated for the detected pesticides classified as possible and potential carcinogens were lower than 1.0 E-06, except for carbendazim and hexythiazox.

Atmospheric degradation of the organothiophosphate insecticide - Pirimiphos-methyl.

The gas phase atmospheric degradation of pirimiphos-methyl (a widely used organophosphate insecticide and acaricide in many European regions) has been investigated at the large outdoor European Photoreactor (EUPHORE) in Valencia, Spain. Its photolysis has been studied under sunlight conditions and its reaction rate constant with OH radicals was measured by the relative rate method. The reaction with ozone was also investigated. The tropospheric degradation of pirimiphos-methyl is controlled mainly by the OH radical reaction. The rate coefficient of the OH reaction with pirimiphos-methyl, k, was measured by a conventional relative rate technique, where aniline was taken as a reference. The resulting value of the OH reaction rate constant with pirimiphos-methyl was k=(1.14±0.2)×10-10cm3molecule-1s-1. The tropospheric lifetime of pirimiphos-methyl with respect to the reaction with OH radicals was estimated to be around 1.6h (283±10) K and atmospheric pressure. Significant aerosol formation was observed in the OH reaction with yields that ranged from 25 to 37%, and with particle diameters below 550nm. This therefore reveals a high human risk due to PM<1, without taking into account the chemical composition of the degradation products. SO2, glyoxal and other oxygenated and nitrogenated compounds were the main degradation products detected.

Insights into the Formation and Evolution of Individual Compounds in the Particulate Phase during Aromatic Photo-Oxidation.

Secondary organic aerosol (SOA) is well-known to have adverse effects on air quality and human health. However, the dynamic mechanisms occurring during SOA formation and evolution are poorly understood. The time-resolved SOA composition formed during the photo-oxidation of three aromatic compounds, methyl chavicol, toluene and 4-methyl catechol, were investigated at the European Photoreactor. SOA was collected using a particle into liquid sampler and analyzed offline using state-of-the-art mass spectrometry to produce temporal profiles of individual photo-oxidation products. In the photo-oxidation of methyl chavicol, 70 individual compounds were characterized and three distinctive temporal profile shapes were observed. The calculated mass fraction (Ci,aer/COA) of the individual SOA compounds showed either a linear trend (increasing/decreasing) or exponential decay with time. Substituted nitrophenols showed an exponential decay, with the nitro-group on the aromatic ring found to control the formation and loss of these species in the aerosol phase. Nitrophenols from both methyl chavicol and toluene photo-oxidation experiments showed a strong relationship with the NO2/NO (ppbv/ppbv) ratio and were observed during initial SOA growth. The location of the nitrophenol aromatic substitutions was found to be critically important, with the nitrophenol in the photo-oxidation of 4-methyl catechol not partitioning into the aerosol phase until irradiation had stopped; highlighting the importance of studying SOA formation and evolution at a molecular level.

Atmospheric degradation of lindane and 1,3-dichloroacetone in the gas phase. Studies at the EUPHORE simulation chamber.

The gas-phase degradation of lindane (γ-isomer of hexachlorocyclohexane) towards OH radical was investigated under atmospheric conditions at the large outdoor European simulation chamber (EUPHORE) in Valencia, Spain. The rate coefficient for the reaction of hydroxyl radicals with lindane was measured using a conventional relative rate technique leading to a value of kOH(lindane)=(6.4±1.6)×10(-13) cm(3) molecule(-1) s(-1) at 300±5 K and atmospheric pressure. The results suggest that the tropospheric lifetime of lindane with respect to OH radicals is approximately 20 days. The product distribution studies on the OH-initiated oxidation of lindane provided evidence that the major initial carbon-containing oxidation product is pentachlorocyclohexanone. 1,3-Dichloroacetone was employed as a model compound for pentachlorocyclohexanone, and an investigation of its photolysis and reaction with OH radicals under atmospheric conditions was carried out. The data indicate that the atmospheric degradation of pentachlorocyclohexanone would be relatively rapid, and would not form persistent organic compounds. Theoretical study was also employed to calculate possible degradation pathways. Mechanism for reaction of lindane with OH radicals is proposed, and C-Cl bond cleavage is discussed. OH abstraction is considered to be a reasonable way for Cl to escape during degradation. The atmospheric implications of the use of lindane as an insecticide are discussed.

Relevant genetic differentiation among Brazilian populations of Anastrepha fraterculus (Diptera, Tephritidae).

We used a population genetic approach to detect the presence of genetic diversity among six populations of Anastrepha fraterculus across Brazil. To this aim, we used Simple Sequence Repeat (SSR) markers, which may capture the presence of differentiative processes across the genome in distinct populations. Spatial analyses of molecular variance were used to identify groups of populations that are both genetically and geographically homogeneous while also being maximally differentiated from each other. The spatial analysis of genetic diversity indicates that the levels of diversity among the six populations vary significantly on an eco-geographical basis. Particularly, altitude seems to represent a differentiating adaptation, as the main genetic differentiation is detected between the two populations present at higher altitudes and the other four populations at sea level. The data, together with the outcomes from different cluster analyses, identify a genetic diversity pattern that overlaps with the distribution of the known morphotypes in the Brazilian area.

Gas-phase and particulate products from the atmospheric degradation of the organothiophosphorus insecticide chlorpyrifos-methyl.

The phosphorothioate structure is highly present in several organophosphorus pesticides. However, there is insufficient information about its degradation process after the release to the atmosphere and the secondary pollutants formed. Herein, the atmospheric reaction of chlorpyrifos-methyl (o,o-dimethyl o-(3,5,6-trichloropyridin-2-yl) phosphorothioate), is described for semi-urban or rural locations. The photo-oxidation under low NOx conditions (5-55 ppbV) was reproduced in a large outdoor simulation chamber, observing a rapid degradation (lifetime<3.5 h). The formation of gaseous products and particulate matter (aerosol yield 2-8%) was monitored. The chemical composition of minor products (gaseous and particulate) was studied, identifying 15 multi-oxygenated derivatives. The most abundant products were ring-retaining molecules such as o,o-dimethyl o-(3,5,6-trichloropyridin-2-yl) phosphorothioate, dimethyl 3,5,6-trichloropyridin-2-yl phosphate, o-methyl o-(3,5,6-trichloropyridin-2-yl) hydrogen phosphorothioate, 3,5,6-trichloropyridin-2-yl dihydrogen phosphate, 3,5,6-trichloropyridin-2-ol, and 3,5,6-trichloropyridine-2,4-diol. An atmospheric degradation mechanism has been proposed based on an oxidation started with OH-nucleophilic attack to P=S bond. The results have been extrapolated to other organothiophosphorus molecules, such as malathion, parathion, diazinon and methidathion, among many others, to estimate their photo-oxidative degradation and the expected products.

Toxic effect of citrus peel constituents on Anastrepha fraterculus Wiedemann and Ceratitis capitata Wiedemann immature stages.

The toxicity of essential oils from the citrus peel has been proposed as the major resistance mechanism offered by citrus to fruit fly infestation. We evaluated the insecticidal activity of the ether extracts from the lemon (Citrus limon [L.] Burm.) and grapefruit (C. paradisi Macfadyen) peel as well as from limonene and citral against Anastrepha fraterculus (Wiedemann) and Ceratitis capitata (Wiedemann) immature stages. We also evaluated the toxicity of the extracts at two ripening stages. Extracts proved toxic to A. fraterculus egg and larvae. The lemon and grapefruit extracts showed the same toxicity in both fruit fly species. For A. fraterculus eggs, citral was more toxic than limonene; for larvae, they showed equal toxicity. Anastrepha fraterculus eggs were more sensitive than C. capitata eggs. In conclusion, we provide evidence of chemical resistance mechanisms that could account for the nonhost condition of lemon for A. fraterculus.

The gas-phase degradation of chlorpyrifos and chlorpyrifos-oxon towards OH radical under atmospheric conditions.

The OH initiated oxidation of chlorpyrifos (a widely used insecticide) and its photooxidation product chlorpyrifos-oxon were investigated at the large outdoor European Photoreactor (EUPHORE). The rate constants for reaction of chlorpyrifos and chlorpyrifos oxon with OH radicals were measured using a conventional relative rate method. The value of the OH reaction rate constants with chlorpyrifos and chlorpyrifos-oxon were determined to be k=(9.1±2.1)×10(-11)cm(3)molecule(-1)s(-1) and (1.7±0.9)×10(-11)cm(3)molecule(-1)s(-1) at 303±5K and atmospheric pressure. They gave an atmospheric lifetime in relation to the reaction with OH of approximately 2h and 11h for chlorpyrifos and chlorpyrifos-oxon, respectively. Photolysis was found to be unimportant relative to reaction with OH. The main products detected in the gas phase from the reaction of OH with chlorpyrifos were SO2, chlorpyrifos-oxon, 3,5,6-trichloro-2-pyridinol and diethylphosphate with molar yields of 17±5%, ∼10%, 8±4% and 30±9%, respectively.

Gas-phase degradation of the herbicide ethalfluralin under atmospheric conditions.

The gas-phase degradation of ethalfluralin, N-ethyl-α,α,α-trifluoro-N-(2-methylallyl)-2,6-dinitro-p-toluidine, a widely used herbicide, was investigated under atmospheric conditions at the large outdoor European simulation chamber (EUPHORE) in Valencia, Spain. The photolysis of ethalfluralin was investigated under solar radiation and the mean photolysis rate coefficient was determined: J(ethalfluralin)=(1.3±0.2)×10(-3) s(-1) (JNO2=8×10(-3) s(-1)). The rate coefficients for the reactions of hydroxyl radicals and ozone with ethalfluralin in the dark were also measured under atmospheric conditions using the relative rate and the absolute rate technique, respectively. The rate coefficients values for the reactions of kOH(ethalfluralin)=(3.5±0.9)×10(-11)cm(3)molecule(-1)s(-1), and kO3(ethalfluralin)=(1.6±0.4)×10(-17) cm(3) molecule(-1) s(-1) were determined at 300±5 K and atmospheric pressure. The results show that removal of ethalfluralin from the atmosphere by reactions with OH radicals (τ ~ 4 h) or ozone (τ ~ 25 h) is slow compared to loss by photolysis. The available kinetic data suggest that the gas-phase tropospheric degradation of ethalfluralin will be controlled mainly by photolysis and provide an estimate for the tropospheric lifetime of approximately 12 min. The atmospheric implications of using ethalfluralin as a herbicide are discussed.

Studies on atmospheric degradation of diazinon in the EUPHORE simulation chamber.

The gas phase atmospheric degradation of diazinon has been investigated at the large outdoor European Photoreactor (EUPHORE) in Valencia, Spain. The rate constant for reaction of diazinon with OH radicals was measured using a conventional relative rate method with di-n-buthylether as reference compound being k = (3.5 ± 1.2) × 10⁻¹¹ cm³ molecule⁻¹ s⁻¹ at 302 ± 10 K and atmospheric pressure. The available evidence indicates that tropospheric degradation of diazinon is mainly controlled by reaction with OH radicals, and that the tropospheric lifetime with respect to the OH reaction is estimated to be around 4h whereas its lifetime with respect to the photolysis is higher than 1d under our conditions. Significant aerosol formation was observed following the reaction of diazinon with OH radicals, and the main carbon-containing products detected in the particle phase were hydroxydiazinon, hydroxydiazoxon and 2-isopropyl-6-methyl-pyrimidinyl-4-ol.

Studies on the atmospheric degradation of chlorpyrifos-methyl.

The gas-phase atmospheric degradation of chlorpyrifos-methyl (a widely used organophosphate insecticide in Southern European regions) has been investigated at the large outdoor European Photoreactor (EUPHORE) in Valencia, Spain. Photolysis under sunlight conditions and reaction with ozone were shown to be unimportant. The rate constant for reaction of chlorpyrifos-methyl with OH radicals was measured using a conventional relative rate method with cyclohexane and n-octane employed as reference compounds with k = (4.1 ± 0.4) × 10(-11) cm(3) molecule(-1) s(-1) at 300 ± 5 K and atmospheric pressure. The available evidence indicates that tropospheric degradation of chlorpyrifos-methyl is mainly controlled by reaction with OH radicals and that the tropospheric lifetime is estimated to be around 3.5 h. Significant aerosol formation was observed following the reaction of chlorpyrifos-methyl with OH radicals, and the main carbon-containing products detected in the gas phase were chlorpyrifos-methyl oxone and 3,5,6-trichloro-2-pyridinol.

Concepções pedagógicas e método de ensino: o manual didático Processologia na Escola Primária / Concepciones pedagogicas y metodo de enseñanza: el manual Processologia na Escola Primária / Pedagogical conceptions and method of teaching: the textbook Processologia na Escola Primária

Esse artigo analisa o manual didático Processologia na Escola Primária, de autoria de Caio de Figueiredo Silva, publicado em 1956, com o objetivo de compreender o processo de incorporação das concepções pedagógicas da Escola Nova nas prescrições para a prática pedagógica. O método empregado foi a análise do discurso expresso na fonte primária aliada a um conjunto de referências bibliográficas de cunho historiográfico que possibilitaram comentar o processo de inovação e permanência na educação, ressaltando as influências de tradições já estabelecidas e a importância dos textos didáticos como instrumentos mediadores para a difusão e circulação de idéias.(AU)

The article focuses on the analysis of the textbook Processologia in Primary School, by Caio de Figueiredo Silva, published in 1956. The goal is to understand the process of incorporating pedagogical conceptions from the Progressive School in prescriptions to the pedagogical practice. The method used was the analysis of speech expressed in primary sources allied to historical references. The textbook allows to elucidate aspects of innovating pedagogical ideas and maintenance processes in education. It seems to be possible to show the influence of established tradition and the importance of textbooks used as instruments for the diffusion and circulation of ideas.(AU)

Ese artículo analiza el manual didáctico Processologia na Escola Primária, de autoría de Caio de Figueiredo Silva, publicado en 1956, con el objetivo de verificar la articulación entre prácticas preescritas y concepciones teóricas. El método usado fue la análisis del discurso expreso en la fuente primaria con analices históricas que posibilitaran comentar el proceso de innovación y permanencia en la educación resaltando la influencia de tradiciones ya establecidas y la importancia de los textos como instrumentos didácticos mediadores para la difusión y circulación de ideas.(AU)

Concepções pedagógicas e método de ensino: o manual didático Processologia na Escola Primária / Concepciones pedagogicas y metodo de enseñanza: el manual Processologia na Escola Primária / Pedagogical conceptions and method of teaching: the textbook Processologia na Escola Primária

Esse artigo analisa o manual didático Processologia na Escola Primária, de autoria de Caio de Figueiredo Silva, publicado em 1956, com o objetivo de compreender o processo de incorporação das concepções pedagógicas da Escola Nova nas prescrições para a prática pedagógica. O método empregado foi a análise do discurso expresso na fonte primária aliada a um conjunto de referências bibliográficas de cunho historiográfico que possibilitaram comentar o processo de inovação e permanência na educação, ressaltando as influências de tradições já estabelecidas e a importância dos textos didáticos como instrumentos mediadores para a difusão e circulação de idéias.

The article focuses on the analysis of the textbook Processologia in Primary School, by Caio de Figueiredo Silva, published in 1956. The goal is to understand the process of incorporating pedagogical conceptions from the Progressive School in prescriptions to the pedagogical practice. The method used was the analysis of speech expressed in primary sources allied to historical references. The textbook allows to elucidate aspects of innovating pedagogical ideas and maintenance processes in education. It seems to be possible to show the influence of established tradition and the importance of textbooks used as instruments for the diffusion and circulation of ideas.

Ese artículo analiza el manual didáctico Processologia na Escola Primária, de autoría de Caio de Figueiredo Silva, publicado en 1956, con el objetivo de verificar la articulación entre prácticas preescritas y concepciones teóricas. El método usado fue la análisis del discurso expreso en la fuente primaria con analices históricas que posibilitaran comentar el proceso de innovación y permanencia en la educación resaltando la influencia de tradiciones ya establecidas y la importancia de los textos como instrumentos didácticos mediadores para la difusión y circulación de ideas.