115 research outputs found

    Impact and prevention of groundwater pollution by pesticides and nitrate in hilly vineyards: evaluation of contamination sources and development of best management practices and mitigation measures

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    Molte attività antropiche danno origine a problemi ambientali per i quali è necessario trovare soluzioni. La presenza di sostanze indesiderabili nell'acqua, infatti, può rappresentare un rischio per la salute e l'igiene sia degli uomini che degli animali. È quindi fondamentale trovare metodi per evitare gli inquinanti di queste matrici, in modo da renderli compatibili con il mantenimento di condizioni ambientali adeguate e salutari. Questa tesi si propone di valutare la qualità delle acque sotterranee di un'area in cui la qualità dell'acqua non è mai stata studiata, in particolare indagando la presenza di pesticidi e nitrati al fine di comprendere l’impatto della viticoltura sull'inquinamento delle acque sotterranee. Questo studio nasce dalla necessità di migliorare la governance delle acque e di implementare le migliori pratiche di gestione e misure di mitigazione per prevenire l'inquinamento delle acque e quello ambientale. I risultati degli studi di monitoraggio hanno mostrato una contaminazione delle acque sotterranee da parte di pesticidi e nitrati e quindi è stata effettuata una valutazione della fonte di contaminazione da pesticidi e nitrati attraverso studi isotopici di N e O di NO3-, e attraverso analisi idrologiche utilizzando il modello CRITERIA 3D. Come una delle principali conclusioni del lavoro si può affermare che la presenza di pesticidi nelle acque sotterranee in un’area ad attività vitivinicola intensa, non può essere correlata solo alle proprietà e al destino chimico-ambientale delle sostanze o alle condizioni pedoclimatiche, ma anche al comportamento dell'utilizzatore finale. In effetti, la fonte di contaminazione valutata, è risultata essere dovuta sia a una contaminazione diffusa che a una contaminazione puntiforme. Per quanto riguarda l'influenza della fertilizzazione a base di azoto sulla presenza di nitrati nelle acque sotterranee, i risultati hanno mostrato un'elevata vulnerabilità dell'acquifero ai cambiamenti esterni. Dalle indagini isotopiche è emerso che la maggior parte dell'NO3- rilevato nelle acque sotterranee, deriva dall'utilizzo di fertilizzanti azotati inorganici, in accordo con le pratiche di uso del suolo e di viticoltura dichiarate dagli agricoltori della zona. Il risultato più importante dello studio, tuttavia, è stato che alla fine del processo, l'approccio multi-actor e la strategia di coinvolgimento adottati, hanno avuto successo nel migliorare gli atteggiamenti verso pratiche più sostenibili.Many anthropic activities give rise to environmental problems for which it is necessary to find solutions. The presence of undesirable substances in water, indeed, can pose a risk to the health and hygiene of both men and animals. It is, therefore, essential to find methods in order to avoid pollutants from these matrices, so as to make them compatible with the maintenance of healthy environmental conditions. This thesis aims to assessing the groundwater quality of an area in which the quality of water was never studied, particularly investigating the occurrence of pesticides and nitrate in order to understand the grant of viticulture on water pollution. This study derives from the necessity to improve the water governance and to implement the best management practices and mitigation measures to prevent groundwater and environmental pollution. The results of monitoring studies showed a contamination of groundwater by pesticides and nitrate and thus an evaluation of PPPs and nitrates source contamination was carried out through isotopic studies of N and O of NO3- , and through hydrologic analysis by use of the model CRITERIA 3D. As one of the main conclusions of the work, the occurrence of PPPs in groundwater in areas with intensive viticultural activities cannot be related just to chemical environmental fate properties or pedoclimatic conditions, but also to end-user behavior. In fact, the contamination source evaluated, resulted to be due to both diffuse and point-source contamination. For what concerns the influence of nitrogen-based fertilization on nitrate occurrence in groundwater, the results showed a high vulnerability of the aquifer to external changes. Isotopic investigations showed that most of the NO3- detected in the groundwater, derived from the use of inorganic nitrogen fertilizers, in agreement with the land use and viticulture practices declared by the farmers. The most important result of the study, however, was that at the end of the overall process, the multi-actor approach and engagement strategy adopted were successful in improving attitudes to more sustainable practices

    Sepiolite with enhanced chemical reactivity as filler for rubber compounds

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    Reinforcing fillers are essential ingredients of rubber composites and, among them, inorganic oxides/hydroxides play a crucial role. Silica, with adequate coupling agents, is the best filler for tyre compounds with low energy dissipation and fuel consumption [1]. In recent years, interest has been increasing for biosourced fillers. Sepiolite is one of the most studied, thanks to its nanometric size and high aspect ratio [1-2]. However, sepiolite can hardly behave as a reinforcing filler, without establishing a chemical interaction with the rubber matrix. It is possible to pursue such objective by using an efficient coupling agent. In this study, sepiolite was functionalized with a pyrrole derivative, (2,5-dimethyl-1-(3-(triethoxysilyl) propyl)-1H-pyrrole) (APTESP), by simply mixing in water and heating, performing first evaporation and then the functionalization reaction. The Sepiolite/APTESP adduct was used as reinforcing filler in NR based composites, as the only filler or in a hybrid filler system with carbon black. The composites were prepared via melt blending in internal mixers. Sulfur based crosslinking was carried out and characterization was performed by means of dynamic-mechanical and tensile tests. Results The adduct Sepiolite/APTESP was successfully prepared, by using water as the reaction medium. The amount of APTESP was between 5 and 10% and the functionalization yield was higher than 70%. Sepiolite promoted the dynamic-mechanical reinforcement of the rubber composites, thanks to APTESP as coupling agent. The mechanical percolation threshold in sepiolite, as the only filler in NR, was observed at a sepiolite content of about 15 phr. When sepiolite/APTESP were used in place of CB, similar or lower values of hysteresis were obtained

    Bionanocomposites based on a covalent network of chitosan and edge functionalized graphene layers

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    Graphene has outstanding thermal, mechanical and electronic properties. Bionanocomposites are an emerging class of materials, designed with the aim of achieving advanced structural and functional properties by using biobased polymers. As biopolymer, a great interest is for chitosan (CS), poly (N-acetyl-D-glucosamine), a copolymer of linked 2-acetamido-2-deoxy-D-glucopyranose and 2-amino-2-deoxy-D-glucopyranose. Graphene and graphene related materials are increasingly used for the preparation of bionanocomposites. In this study, a high surface area graphite was edge functionalized with hydroxyl groups (G-OH) through the reaction with KOH. G-CHO, with 4.5 mmol/g of functional group, was prepared from G-OH by means of the Reimer-Tieman reaction. Carbon papers and aerogels were prepared from chitosan and graphene layers with aldehydic edge functional groups (G-CHO) able to form chemical bonds with chitosan and thus to form a crosslinked network. Characterization of the graphitic materials was performed with elemental analysis, titration, X-ray analysis and Raman spectroscopy. CS and G-CHO were mixed with mortar and pestle and carbon papers and aerogels were obtained from a stable acidic water suspension through casting and liophilization, respectively. This work demonstrates that carbon papers and aerogels can be prepared without adopting the traditional oxidation-reduction procedure, avoiding harsh reaction conditions, dangerous and toxic reagents, solvents and catalysts and paves the way for selective modification of graphene layers, exploiting the reactivity of aromatic rings

    Bionanocomposites based on chitosan and few layers graphene. The effect of tailor-made functionalization

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    Bionanocomposites are an emerging class of material. They are designed and developed to achieve advanced structural and functional properties, by using biobased polymers. Among the bio-polymers, focus is on chitosan (CS), poly (N-acetyl-D-glucosamine), a copolymer of [1,4]-linked 2-acetamido-2-deoxy-D-glucopyranose and 2-amino-2-deoxy-D-glucopyranose. Research is steadily increasing on bionanocomposites with graphene and graphene related materials. It is here presented a research on bionanocomposites based on CS and graphene layers (G). Particular focus of the research was on the integration of the graphene layers in the nanocomposite. Materials were prepared based on the supramolecular interaction between CS and G. The core of the research was then on the edge functionalization of the layers. OH groups were added through the cycloaddition reaction with a biosourced pyrrole compound, serinol pyrrole (SP), carried out with the help of either thermal or mechanical energy, with an atom efficiency up to 96% and a very low E Factor. The preparation of CS/G adducts was very simple, even by using only mortar and pestle. OH groups were also added to the G edges by performing the reaction of G with KOH. The Reimer-Tiemann reaction on the G-OH adduct led to the introduction of aldehydic groups, which promote the crosslinking of CS. The CS/G adducts were characterized by means of wide angle X-ray diffraction, scanning and transmission electron microscopy, Fourier transform infrared, X-ray photoelectron and Raman spectroscopies. Thermal stability of the composites was studied by thermogravimetric analysis. Carbon papers and aerogels were prepared, studying the flexibility and the stability in various solvents in a wide pH range

    First evaluation of pesticides occurrence in groundwater of Tidone Valley, an area with intensive viticulture.

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    Abstract Agricultural practice often involves an intensive and incorrect use of pesticides and fertilizers. These chemicals can leach through the soil profile and contaminate groundwater, including drinking water. For this reason, an effective groundwater monitoring is strongly advisable. The aim of this study was to investigate the groundwater contamination by plant protection products (PPPs) on a hilly area situated in the Tidone Valley, North-West of Italy, a region characterized by an intensive viticulture production. This area is not included in the national groundwater monitoring plan and therefore scarce information is available regarding the quality of groundwater, even though the local Environmental Agency previously revealed the occurrence of PPPs at values higher than the Environmental Quality Standard downstream this area. Hence, a monitoring wells network was developed following an upstream-downstream criterion, a list of pesticides to be monitored, based on a multi-actor approach, and an analytical method for PPPs detection and quantification. The analytical approach involved solid phase extraction followed by High-Performance Liquid Chromatography tandem mass spectrometry. The results of three monitoring campaigns revealed the occurrence of seven PPPs at a level higher than EQS for groundwater (0.1 μg/L) in 30% of the wells. The main pesticides detected were Chlorantraniliprole, Dimethomorph, Fluopicolide, Metalaxyl-M, Penconazole, and Tetraconazole, all commonly used in viticulture, together with S-metolachlor, authorized for cereal cropping. Statistical analysis revealed a significant influence of the sampling time, slope of the soil surrounding the wells, wells depth and wells location on the concentration of five PPPs. Therefore, the results obtained show that the improper use of PPPs for grapevine cultivation may cause groundwater contamination and suggest the need for a deeper analysis of territorial reality, including hydrology studies and farmer behavior and for an urgent introduction of best management practices and mitigation measures to promote a sustainable use of PPPs in viticulture

    Multi-actor approach and engagement strategy to promote the adoption of best management practices and a sustainable use of pesticides for groundwater quality improvement in hilly vineyards.

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    The adoption of pesticide mitigation measures and innovation at farm level, are seen as a drivers to reach the sustainable water policy objectives. With the aim to prevent the pesticide pressure of hilly vineyards on groundwater contamination, a stepwise approach in Tidone Valley was applied using different consultation mechanisms and involvement strategies throughout the overall process. Face to face meetings, direct surveys, participatory monitoring and planning of several activities aiming to inform, educate, improve skills, change of individual behaviour or raise awareness, or even initiatives to build institutional trust or support for new investment in innovation are some examples. These activities allowed us to involve key actors of water use and governance (such as farmers, advisors, representatives of drinking water management, farmer's associations, Winemaking cooperatives, local Health Authority), and to have a deeper knowledge of the context agricultural practices, of farmer's knowledge and skills concerning factors influencing water contamination and also to promote the most suitable Best Management Practices aimed at limiting the pesticide occurrence in groundwater. Indeed, the surveys results highlighted that the majority of the farms are small (64% of vineyards10 ha), that most of the farmers (62%) are not aware of the current legislation on water, even if 64% of them declare to participate regularly to training courses for the prevention of water contamination and that there is a low to moderate level of adoption of Best Practices able to prevent contamination by pesticides. At the end of the overall process, it can be stated that the multi-actor approach and engagement strategy adopted were successful in improving attitudes to more sustainable practices. This is supported also by the monitoring data that show in 2019 a decrease by 44% of pesticides occurrences and a fall by 68% of values above EQ

    Pain processing in functional and idiopathic dystonia: An exploratory study.

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    BACKGROUND: Pain is often experienced by patients with functional dystonia and idiopathic cervical dystonia and is likely to be determined by different neural mechanisms. OBJECTIVE: In this exploratory study, we tested the sensory-discriminative and cognitive-emotional component of pain in patients with functional and idiopathic dystonia. METHODS: Ten patients with idiopathic cervical dystonia, 12 patients with functional dystonia, and 16 age- and sex-matched healthy controls underwent psychophysical testing of tactile and pain thresholds and pain tolerance. We delivered electrical pulses of increasing intensity to the index finger of each hand and the halluces of each foot. Pain threshold and pain tolerance were respectively defined as the (1) intensity at which sensation changed from unpainful to faintly painful and (2) intensity at which painful sensation was intolerable. RESULTS: No differences were found between the three groups for tactile and pain thresholds assessed in hands and feet. Pain tolerance was significantly increased in all body regions only in functional dystonia. Patients with continuous functional dystonia had higher pain tolerance compared to subjects with paroxysmal functional dystonia and idiopathic cervical dystonia. There was no correlation between pain tolerance and pain scores, depression, anxiety, disease duration, and motor disability in both groups. CONCLUSIONS: Patients with functional dystonia have a dissociation between the sensory-discriminative and cognitive-emotional components of pain, as revealed by normal pain thresholds and increased pain tolerance. Abnormal connectivity between the motor and limbic systems might account for abnormal pain processing in functional dystonia. © 2018 International Parkinson and Movement Disorder Society

    Functionalization of graphene related materials with biosourced C-3 and C-6 building blocks. From synthesis to applications

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    The functionalization of sp2 carbon allotropes is one of the hot research topics in advanced research on materials. Nowadays, carbon nanotubes and graphene related materials are extensively studied due to their exceptional mechanical and electrical properties. They are capable of substantially improving the properties of polymeric materials. Their functionalization is a crucial step, for allowing an even dispersion in the matrix. In this research, the functionalization of graphene related materials was performed with biosourced C-3 and C-6 molecules. They were glycerol and galactaric acid derivatives: pyrrole compounds (PyC) and 2-pyrones. The reactions for their synthesis and for the carbon allotrope functionalization were green and characterized by high atom efficiency, with a yield up to 96%. Indeed, the reactions were carried out in the absence of solvents and catalysts and adducts were obtained by simply mixing, with the help of either thermal or mechanical energy. The developed functionalization methods were successful for: carbon black, carbon nanotubes, few layers graphene. The bulk structure of the carbon substrate was left substantially unaltered: functionalization occurred in peripheral positions, at the edges of the graphene layers. Functional groups of defined chemical structure were covalently bound to the carbon material and stable adducts, up to very high temperature, were formed. Reliable hypotheses for the functionalization mechanisms were elaborated. In Figure 1b the supposed domino reaction based on the pyrrole compound, with the Diels Alder cycloaddition as the last step is represented. Such functionalization technique was developed as a pervasive technology, which allowed to pursue a variety of applications: (i) decoration with metals to obtain catalysts for the selective deuteration of pharmaceutical molecules as well as antibacterial ingredients (ii) rubber compounds for dynamic-mechanical applications (tires) (iii) conductive inks

    Evaluation of groundwater contamination sources by plant protection products in hilly vineyards of Northern Italy

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    Abstract In Europe, 25% of groundwater has poor chemical status. One of the main stressors is agriculture, with nitrates and plant protection products (PPPs) causing failure in 18% and 6.5%, respectively, of groundwater bodies (by area). EU legislation for the placement of the PPPs on the market is one of the most stringent in the world. However, recent monitoring studies in hilly vineyards of Tidone Valley, north-west of Italy, show presence of PPPs used for grapevine cultivation in 15 out of 26 groundwater wells monitored, at values above the Environment Quality Standard (EQS) for groundwater (0.1 μg/L). However, no information about the contamination sources are available. Therefore, the objective of the present work is to evaluate the groundwater contamination sources by PPPs, in a small catchment with intensive viticulture, by collecting and integrating monitoring data, sub-surface water movement data and territorial characteristics. The results show that in wells used for PPP's mixture preparation and sprayer washing located at the top of hilly vineyards, with low slope and no water movement in the surrounding soil, the contamination is most likely from point sources. On the contrary, for wells located in a fenced area at the bottom of the hill, far away from vineyards and being used for drinking water production, the contamination is most likely from diffuse sources. Our results were used to raise awareness on groundwater contamination from PPPs among farmers in the study area; moreover a waterproof platform for sprayers washing, equipped with wastewater recovery and disposal system, able to avoid point-source contamination, was implemented in a local demonstration farm. Several demonstration activities were then organised with the farmers of the entire Valley in order to show its functionality and promote its diffuse use

    A longitudinal study of brain atrophy and cognitive disturbances in the early phase of relapsing-remitting multiple sclerosis

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    Objective—(a) To establish whether the cognitive decline of the early phase of relapsing-remitting multiple sclerosis depends on the progression of the burden of disease, or on the loss of brain parenchyma, or is influenced by both; (b) to monitor the loss of brain parenchyma in the early phase of the disease; and (c) to examine its possible relation with the progression of physical disability. Methods—For 2 years 53 patients with clinically definite relapsing-remitting multiple sclerosis with disease duration 1–5 years and expanded disability status scale<5.0 at baseline were monitored.The neuropsychological performances, the psychological functioning, the neurological impairment, and the disability have beenassessedatbaselineandafter2years. Patients also underwent PD/T2 and T1 weighted brain MRI.T2 and T1 lesion volumes were measured by a semiautomatic technique. Quantification of brain parenchymal volumes was obtained using a highly reproducible computerised interactive program. The relation between cognitive impairment and MRI findings has been investigated by partial correlation and stepwise multiple regression analyses excluding the eVects of age, education, anxiety, depression, and total days of steroid use. Results—In the 2 years of the study the meanchangeforT2andT1lesionvolumes and brain parenchymal volumes were +1.7 ml (95% confidence interval (95% CI) 1.3– 2.2, p=0.005, (29.8%); +0.2 ml, 95% CI 0.15–0.26, p=0.004, (25%); and –32.3 ml, 95% CI 24.2–42.3, p<0.0001, (2.7%), respectively. Overall, 14 patients (26.4%) were judged to be cognitively impaired at baseline and 28 (52.8%) at the end of the follow up. Of the 18 neuropsychological tests and subtests employed in the study, patients with multiple sclerosis failed 5.8 (SD 2.3) tests at the baseline and 8.4 (SD 2.9) (p<0.0001) tests at the end of the study. When the cognitive changes were examined in individual patients, five (9.4%) of them were considered cognitively improved, 33 (62.3%) remained stable, and 15 (28.3%) worsened over 2 years. T2 and T1 volume changes in improved, stable, and worsened patients did not show any significant diVerence, whereas brain parenchymal volume decrease in cognitively worsened patients was significantly greater (−66 ml (5.4%), 95% CI 37–108.9, p=0.0031). The cognitive impairment was independently predicted over 2 years only by the change of brain parenchymal volumes (R=0.51, p=0.0003). Ten patients (18.9%), who worsened by one or more points in the EDSS during the follow up period had significant decreases in brain parenchymal volumes (−99 ml (8%),95% CI 47.6–182.3,p=0.005). At the end of the study the loss of brain parenchyma correlated significantly with change in EDSS (r= 0.59, p<0.0001). Conclusions—In the early phase of relapsing-remitting multiple sclerosis the cognitive deterioration relies more on the development of brain parenchymal volume atrophy than on the extent of burden of disease in the brain. The loss of brain parenchymal volume underlies the progressive accumulation of physical disability from the initial phase of the disease, which becomes more demonstrable only if studied with longer observation periods. Probably, the main pathological substrate of brain atrophy in the early stage of the disease is early axonal loss, which causes the progression of neurological deficits and the development of cognitive impairment. These data support the debated opinion that disease modifying therapy should be initiated as early as possible
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