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Abstract This study investigates the adsorption and dissipation of glyphosate and the formation/dissipation of AMPA in non-tilled (NT) and conventionally tilled (CT) soil at 0–5 and 5–20 cm depth. Glyphosate adsorption was mainly related to the different NT and CT soil properties (clay and amorphous Al oxides), whereas an effect of the soil management could not be identified. Glyphosate dissipation was initially fast, and it slowed down later. The initial glyphosate concentration in NT soil at 0–5 cm was significantly lower than the dose applied due to the interception by the weeds and crop residues. AMPA began to form early after treatment and persisted longer than glyphosate. The DT50 range was 8–18 days for glyphosate and 99–250 days for AMPA. Longer glyphosate and AMPA DT50 were observed in NT soil compared to CT soil but, for glyphosate, the difference was significant only at 5–20 cm. Higher glyphosate and AMPA concentrations were detected in NT than in CT soil at the end of the study at 0–5 cm. The differences in glyphosate and AMPA DT50 and persistence were mainly attributable to the influence of different NT and CT soil characteristics. However, other factors could have contributed to the different glyphosate and AMPA dynamics between the soils, like glyphosate wash-off from crop residues on NT soil with the rainfall, the delayed glyphosate return to the soil by weed root exudation or weeds decomposition, and the NT soil compaction which may have reduced the microbial degradation of glyphosate at low concentrations. Graphic abstract

Oligodendrocytes are implicated in amyotrophic lateral sclerosis pathogenesis and display transactive response DNA-binding protein-43 (TDP-43) pathological inclusions. To investigate the cell autonomous consequences of TDP-43 mutations on human oligodendrocytes, we generated oligodendrocytes from patient-derived induced pluripotent stem cell lines harbouring mutations in the TARDBP gene, namely G298S and M337V. Through a combination of immunocytochemistry, electrophysiological assessment via whole-cell patch clamping, and three-dimensional cultures, no differences in oligodendrocyte differentiation, maturation or myelination were identified. Furthermore, expression analysis for monocarboxylate transporter 1 (a lactate transporter) coupled with a glycolytic stress test showed no deficit in lactate export. However, using confocal microscopy, we report TDP-43 mutation-dependent pathological mis-accumulation of TDP-43. Furthermore, using in vitro patch-clamp recordings, we identified functional Ca2+-permeable α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor dysregulation in oligodendrocytes. Together, these findings establish a platform for further interrogation of the role of oligodendrocytes and cellular autonomy in TDP-43 proteinopathy.

Oligodendrocytes are implicated in amyotrophic lateral sclerosis pathogenesis and display transactive response DNA-binding protein-43 (TDP-43) pathological inclusions. To investigate the cell autonomous consequences of TDP-43 mutations on human oligodendrocytes, we generated oligodendrocytes from patient-derived induced pluripotent stem cell lines harbouring mutations in the

A soil and an organic biomix (soil/vine branch/garden compost 20/40/40) were used in this lab experiment to evaluate adsorption and degradation parameters for three pesticides (chlorpyrifos, metalaxyl and cymoxanil) used in a vineyard. Adsorption in the biomix material was higher than in the soil for the three pesticides and chlorpyrifos was the most adsorbed pesticide. The role of the organic carbon is essential for enhancing the adsortion of the three pesticides, especially for the most apolar chlorpyrifos. Degradation was generally faster in the biomix material than in the soil although the process was slower in the case of chlorpyrifos if compared with the other two chemicals, due to a more toxic effect of this pesticide on soil microflora and a larger adsorption of this pesticide on the organic biomix that reduces its availability for dissipation. Amendment with cheap and available organic wastes or a grass-covered management of soil in the vineyard could reduce the impact of pesticides in the vineyard ecosystem and contribute to the sustainable management of chemicals in the environment.

We describe a research project about the teaching of non-Euclidean geometries. Our intent is to show that non-Euclidean geometries can be a tool to promote the understanding of the modern axiomatic method in mathematics, to stimulate students' aptitudes to logical thinking and to allow students to consolidate the knowledge of Euclidean geometry by developing it in a critical way.

In alpine environments, colonies of snow vole (Chionomys nivalis Martins) cause strong pedoturbation, which may affect humification process and soil organic matter (SOM) cycling, with repercussions on the hormone‐like activity of organics. We investigated the effect of snow vole pedoturbation on the chemical and spectroscopic features of soil organic fractions, and the potential hormone‐like activity of humic and fulvic acids (HA, FA). The study site was located on the high‐mountain environment of the Majella massif (central Italy). Pedoturbated and regular soils were morphologically described and characterized for pH and content of total organic carbon, total extractable carbon, HA, and FA. Both HA and FA were extracted and investigated using attenuated total reflectance/Fourier transform infrared (ATR/FTIR), nuclear magnetic resonance with high‐resolution magic angle spinning (HRMAS‐NMR), and 1H‐13C heteronuclear single quantum coherence (HSQC). HA and FA were also tested for their auxin‐like and gibberellin‐like activities. Results provide evidences that bioturbated and regular soils contain a poorly decomposed SOM, but HA and FA with a well‐defined molecular structure. The HA and FA from both bioturbated and regular soils show a hormone‐like activity with a different allocation along the soil profile. In the regular soil, the highest auxin‐like activity was shown by HA and FA from Oe1 horizon, while gibberellin‐like activity was expressed by FA from Oe2 horizon. Burrowing activity determines a redistribution of organics throughout the profile with a relatively high auxin‐like activity in the FA from straw tunnel wall (STW) and gibberellin‐like activity in the HA from vole feces (VF). The relative high presence of carboxylic acids, amides, proteins, and amino acids in the FA from STW and the aromatic moieties in the HA from VF put evidences for their different behavior. The fact that snow vole activity has modified the chemical and biological properties of SOM in these soils otherwise considered governed only by low temperature has important ecological implications such as the preservation of soil fertility and vegetal biodiversity.

Biochar is used as soil amendment and enhancer of plant growth, but the mechanisms involved in grapevine are not understood. In this study, the short-term effects of amendments were evaluated in a trial combining three substrates (biochar, compost, peat-based media) with three doses (30, 70, 100%) along a time sequence on 1-year-old bare root cuttings of grapevine. Amendments were analyzed for elemental composition. Soil pH, electrical conductivity (EC), chlorophyll (CHL), flavonoids (FL), anthocyans (ANT) and nitrogen balance index (NBI) were measured.Biochar differed from other amendments for stable C structures, where nutrients and lignin residues were high in compost. Biochar increased soil pH, whereas biochar plus compost mixture augmented EC. The amended plants had detrimental effects on root, true and lateral leaves. Nevertheless, at the lowest rate biochar increased the primary shoot and total scion to root biomass ratio. Among biochemicals, ANT and NBI were mostly affected by biochar, while compost gave only slight increments. Thus, although biochar rate was not adequate for the shedding in open field our results suggest that biochar might be useful in nursery when used at low dosages.

Narrow vegetative filter strips proved to effectively reduce herbicide runoff from cultivated fields mainly due to the ability of vegetation to delay surface runoff, promote infiltration and adsorb herbicides. A field trial was conducted from 2007 to 2009 in north-east Italy in order to evaluate the effectiveness of various types of vegetative filter strips to reduce spring-summer runoff of the herbicides mesotrione, metolachlor and terbuthylazine, widely used in maize, and to evaluate the effect of the rainfall characteristics on the runoff volume and concentration. Results show that without vegetative filter strip the herbicide load that reaches the surface water is about 5–6 g ha −1 year −1 for metolachlor and terbuthylazine (i.e. 0.5–0.9% of the applied rate), confirming that runoff from flat fields as in the Po Valley can have a minor effect on the water quality, and that most of the risk is posed by a few, or even just one extreme rainfall event with a return period of about 25–27 years, causing runoff with a maximum concentration of 64–77 μg L −1 . Mesotrione instead showed rapid soil disappearance and was observed at a concentration of 1.0–3.8 μg L −1 only after one extreme (artificial) rainfall. Vegetative filter strips of any type are generally effective and can reduce herbicide runoff by 80–88%. Their effectiveness is steady even under severe rainfall conditions, and this supports their implementation in an environmental regulatory scheme at a catchment or regional scale.

Introduction In intensive agriculture areas the use of pesticides can alter soil properties and microbial community structure with the risk of reducing soil quality. Materials and Methods In this study the fatty acid methyl esters (FAMEs) evolution has been studied in a factorial lab experiment combining five substrates (a soil, two aged composts and their mixtures) treated with a co-application of three pesticides (azoxystrobin, chlorotoluron and epoxiconazole), with two extraction methods, and two incubation times (0 and 58 days). FAMEs extraction followed the microbial identification system (MIDI) and ester-linked method (EL). Results and Discussion The pesticides showed high persistence, as revealed by half-life (t1/2) values ranging from 168 to 298 days, which confirms their recalcitrance to degradation. However, t1/2 values were affected by substrate and compost age down to 8 days for chlorotoluron in S and up to 453 days for epoxiconazole in 12M. Fifty-six FAMEs were detected. Analysis of variance (ANOVA) showed that the EL method detected a higher number of FAMEs and unique FAMEs than the MIDI one, whereas principal component analysis (PCA) highlighted that the monosaturated 18:1ω9c and cyclopropane 19:0ω10c/19ω6 were the most significant FAMEs grouping by extraction method. The cyclopropyl to monoenoic acids ratio evidenced higher stress conditions when pesticides were applied to compost and compost+soil than solely soil, as well as with final time. Conclusion Overall, FAMEs profiles showed the importance of the extraction method for both substrate and incubation time, the t1/2 values highlighted the effectiveness of solely soil and the less mature compost in reducing the persistence of pesticides.

Compost biobeds can promote biodegradation of pesticides. The microbial community structure changes during the composting process, and simple methods can potentially be used to follow these changes. In this study the microbial identification (MIDI) and ester-linked (EL) procedures were used to determine the composition of fatty acid methyl esters (FAMEs) in composts aged 3 and 12 months, inoculated with 3 recalcitrant pesticides (azoxystrobin, chlorotoluron, and epoxyconazole and a coapplication of all three) after 0, 56, and 125 days of degradation. Pesticide persistence was high, and after 125 days the residue was 22 to 70% of the applied amount depending mostly on the composting age. Seventy-one FAMEs belonging to nine groups were detected. The EL method provided three times as many detections as did the MIDI method and was more sensitive for all FAME groups except alcohol. Thirty-six and five FAMEs were unique to the EL and MIDI methods, respectively. The extraction method was of importance. The EL method provided a higher number of detections for 57 FAMEs, and the MIDI method provided a higher number for 9 FAMEs, while the two methods were equal for 5 FAMEs; thus, the EL method provided a more uniform overall FAME profile. Effects of the other factors were not always clear. Inoculation with pesticide did not influence the FAME profile with the MIDI method, while it influenced cyclopropane and monounsaturated content with the EL method. Composting age and degradation time had an effect on some groups of FAMEs, and this effect was greater with the EL method. The use of some FAMEs as biomarkers to follow microbial community succession was likely influenced by the type of compost and other factors.

A 180 d laboratory experiment was conducted to investigate the degradation rates of chlorpyrifos (10 and 50 mg kg−1) and metalaxyl (100 mg kg−1) separately and co-applied in a biomix constituted by topsoil, vine-branches and urban-waste-garden compost. The effect of repeated application of metalaxyl was also investigated. Microbial biomass-C (MBC) content and metabolic quotient (qCO2) were measured to evaluate changes in microbial biomass size and activity induced by the presence of the two pesticides. Degradation rate decreased with increasing concentration of chlorpyrifos in all treatments. Metalaxyl half-life was significantly reduced in co-application with chlorpyrifos indicating a synergic interaction between the two pesticides in favour of enhanced degradation rate for metalaxyl but not for chlorpyrifos. Furthermore, repeated application resulted in a sharp reduction of metalaxyl half-life from 37 d after first application to 4 d after third application. MBC content was negatively influenced by the addition of pesticides but it started to recover immediately, in both separate and co-applied treatments, reaching the control value when pesticide residues were about 50% of the initial concentration. The qCO2 reached a steady-state after about 20 d in separately applied and 40 d in co-applied treatments, indicating a tendency to arrive at a new metabolic equilibrium. In conclusion, the biomix tested has been shown to degrade pesticides relatively fast and to have a microbial community that is varied enough to allow selection of those microorganisms able to degrade metalaxyl and chlorpyrifos.

Biobeds provide a simple and cheap solution to reducing point-source contamination by pesticides from farm activities. In its original design, the Swedish biobed is a clay-lined pit in the ground filled with a biomixture of topsoil, peat and straw and covered with a grass layer. The straw stimulates the growth of lignin-degrading fungi and the formation and activity of ligninolytic enzymes which can degrade many different pesticides. Here we compared the behaviour of the chlorpyrifos pesticide in two biobeds of different composition: a Swedish biobed composed of 50%v vine straw, 25%v peat and 25%v Swedish soil; and an Italian biobed composed of 40%v vine straw, 40%v green compost and 20%v Italian soil. Microbial biomass was measured in the Italian biomix by the fumigation-extraction method. The microbial activity was estimated by measuring mineralisation of a synthetic lignin, 14C-de-hydrogenative polymerisate (14C-DHP) in the Swedish biomix. Microbial respiration was followed over time in both biomixes. Our results show that the chlorpyrifos half-lives were similar in both biomixes. The microbial biomass content was reduced by 25 and 50% with, respectively, 10 and 50 mg kg−1 chlorpyrifos in the Italian biomix. The respiration activity was affected only at 50 mg kg−1 chlorpyrifos in the Italian biomix. No effect was observed in the Swedish biomix despite the higher chlorpyrifos concentration of 100 mg kg−1. The mineralisation of 14C-DHP was not affected by the presence of chlorpyrifos in the Swedish biomix. These findings could be explained by the presence of chlorpyrifos-sensitive microorganisms in the Italian biomix and chlorpyrifos-resitant microorganisms in the Swedish biomix. The more robust microftora developed in the Swedish biomix may be explained by its lower nitrogen content, higher C/N ratio and lower pH, all of which are favourable for the development of lignin-degrading fungi and their activity. In Sweden more than 1000 biobeds are in practical use on farms and they have been shown to be efficient at reducing pesticide water-body contamination. The present study compares the capability of an Italian biomix for degrading pesticides to that shown by the Swedish original biomix in order to introduce this biological system for a sustainable Italian agriculture.