Exposure of coastal dune vegetation to plastic bag leachates: A neglected impact of plastic litter

The presence of plastic bags on coastal dunes worldwide is well documented. Plastic bags contain additives that during rainfall events can leach out from bags into sand dune and be absorbed by seeds and roots of plants. Dune plants play a fundamental role in dune system formation, yet the possible impact of bag leaching on their establishment and development has been neglected. We assessed in laboratory whether (i) not biodegradable bags (high-density polyethylene, PE) and new generation of compostable bags (Mater-bi®, MB) would influence via leaching water chemical/physical properties and (ii) leachates would affect germination and seedling growth using Thinopyrum junceum and Glaucium flavum as models. Leachates were obtained from different amounts of not-exposed and bags exposed to beach or marine conditions simulating various pollution degrees (none, low, intermediate and high pollution). All water variables were affected by leaching. The magnitude of these alterations depended on bag type and environmental exposure. Seeds of T. junceum treated with the high concentration of marine-exposed MB bag leachate germinated later than controls while those of G. flavum treated with the remaining leachates germinated earlier. For both species, leachates from the low concentration of PE and MB marine-exposed bags increased seed germinability. A short radicle was observed in T. junceum seedlings treated with not-exposed MB bag leachates. Glaucium flavum seedlings treated with beach- and marine-exposed PE bags and not-exposed MB bags leachates showed a greater below-aboveground length ratio and those grown with the low concentration of not-exposed PE bag leachate had a longer hypocotyl compared to controls. Leachates from the high concentration of PE and MB bag caused seedling anomalies in both species. These findings indicate that not biodegradable and compostable bags may interact with abiotic/biotic factors and affect via leaching germination phenology, seedling establishment and plant interactions with consequences on dune community structure

Improvement in Wear Resistance of Grade 37 Titanium by Microwave Plasma Oxy-Carburizing

Grade 37 titanium is widely used in racing applications thanks to its oxidation resistance up to 650 °C, but it suffers from poor wear and fretting resistance, especially at high temperature. In this paper, different surface modification techniques, namely, carburizing, coating by PVD-ZrO2 and a novel microwave plasma oxy-carburizing treatment, are investigated in terms of hardness, wear resistance and scratch hardness, compared to the untreated substrate. Numerical simulation allowed optimization of the design of the microwave plasma source, which operated at 2.45 GHz at atmospheric pressure. The proposed microwave plasma oxy-carburizing treatment is localized and can serve to improve the tribological properties of selected regions of the sample; compared to untreated Grade 37 titanium, the oxy-carburized layer presents a decrease in the wear rate at 450 °C against alumina of 54% and an increase in scratch hardness of more than three times

Global change and response of coastal dune plants to the combined effects of increased sand accretion (burial) and nutrient availability

Coastal dune plants are subjected to natural multiple stresses and vulnerable to global change. Some changes associated with global change could interact in their effects on vegetation. As vegetation plays a fundamental role in building and stabilizing dune systems, effective coastal habitat management requires a better understanding of the combined effects of such changes on plant populations. A manipulative experiment was conducted along a Mediterranean dune system to examine the individual and combined effects of increased sediment accretion (burial) and nitrogen enrichment associated with predicted global change on the performance of young clones of Sporobolus virginicus, a widespread dune stabilizing species. Increased burial severity resulted in the production of taller but thinner shoots, while nutrient enrichment stimulated rhizome production. Nutrient enrichment increased total plant biomass up to moderate burial levels (50% of plant height), but it had not effect at the highest burial level (100% of plant height). The effects of such factors on total biomass, shoot biomass and branching were influenced by spatial variation in natural factors at the scale of hundreds of metres. These results indicate that the effects of burial and nutrient enrichment on plant performance were not independent. Their combined effects may not be predicted by knowing the individual effects, at least under the study conditions. Under global change scenarios, increased nutrient input could alleviate nutrient stress in S. virginicus, enhancing clonal expansion and productivity, but this benefit could be offset by increased sand accretion levels equal or exceeding 100% of plant height. Depletion of stored reserves for emerging from sand could increase plant vulnerability to other stresses in the long-term. The results emphasize the need to incorporate statistical designs for detecting non-independent effects of multiple changes and adequate spatial replication in future works to anticipate the impact of global change on dune ecosystem functioning. Citation

Combined effect of plastic litter and increased atmospheric nitrogen deposition on vegetative propagules of dune plants: a further threat to coastal ecosystems

Large amounts of non-biodegradable plastics are currently deposited on beach-dune systems, and biodegradable plastics could enter these already declining habitats in coming years. Yet, the impacts of plastics on vegetative recruitment, a plant strategy playing a key role in dune stabilization, are unknown. Whether these pollutants interact with increased atmospheric nitrogen (N) deposition, a major global driver of plant biodiversity loss, in affecting plant communities of such nutrient-poor habitats, and how plant-plant interactions mediate their effects need to be explored. In a one-year field experiments, we examined individual and combined effects of plastic (non-biodegradable, biodegradable), N deposition (ambient, elevated) and biotic condition (no interaction, interaction with a conspecific or with a hetero-specific) on the colonization success and growth of vegetative propagules of dune plants. Thinopyrum junceum and Sporobolus pumilus were chosen as models because they co-occur along Mediterranean dunes and differ in ecological role (dune- vs. non dune-building) and photosynthetic pathway (C3 vs. C4). For both species, survival probability was reduced by non-biodegradable plastic and elevated N by up to 100%. Thinopyrum junceum survival was also reduced by S. pumilus presence. Elevated N and biodegradable plastic reduced T. junceum shoot biomass when grown alone and with a conspecific, respectively; these factors in combination mitigated their negative individual effects on root biomass. Biodegradable plastic increased S. pumilus shoot and root biomass, and in combination with elevated N caused a greater biomass investment in belowground (root plus rhizome) than aboveground organs. Non-biodegradable plastic may be a further threat to dune habitats by reducing plant colonization. Biodegradable plastic and increased N deposition could favour the generalist S. pumilus and hinder the dune-building T. junceum. These findings highlight the urgency of implementing measures for preventing plastic deposition on beaches and reducing N input

Feasibility study into a scientific self-sampling programme for the pelagic sector : FIS020

Publisher PD

Efficacy and safety of felbamate in children under 4 years of age: a retrospective chart review.

Background and purpose: To review our experience of the efficacy and tolerability of felbamate in children younger than 4 years. Methods: We used a retrospective chart review to identify 53 children with seizures who were younger than 4 years. Efficacy was evaluated based on the occurrence of responsiveness, defined as seizure frequency reduction of more than 50% for a minimum period of 4 months. Tolerability was based on parent-reported side effects. Results: Twenty-two (41%) patients resulted to be responders and 31 (59%) did not. By univariate analysis, those achieving seizure remission were probably much older, to have a shorter history of epilepsy and a lower frequency of seizures before felbamate therapy. The number of antiepileptic drugs (AEDs) used before felbamate therapy was the only significant predictor of the duration of response to felbamate, with a longer responsiveness to the drug seen in those who were placed under fewer than three AEDs before felbamate compared with those who had taken more than three (median, 16 months vs. 7 months; P < 0.0084). Side effects occurred in 30% of the subjects, but these did not require discontinuation of the drug. Discussion: Felbamate is an effective medication for a wide range of epilepsy syndromes in children younger than 4 years. Although caution is necessary when the drug is used in children, felbamate might represent a possible option for the treatment of epilepsy in this age group. Introduction The incidence of epilepsy is high during the first year of life and it declines steadily during childhood and adolescence. Few of the new antiepileptic drugs (AEDs) are indicated officially for children younger than 4 years [1–3]. None of them is approved for children younger than 2 years [1,3,4]. There is a striking discrepancy between the high incidence of epilepsy in infancy and the relatively few approved AEDs available for this age group [5]. Felbamate (2-phenyl-1,3-propanediol dicarbamate) is a derivative of the anti-anxiety drug meprobamate, exerting additional anticonvulsant and neuroprotective properties [6–8]. The drug has been approved since 1993 for the treatment of several types of epilepsy. Experimental studies suggested that felbamate might inhibit voltage-dependen

A Multi-Physic Modelling Insight into the Differences between Microwave and Conventional Heating for the Synthesis of TiO2 Nanoparticles

Microwave-assisted synthesis of nanoparticles usually leads to a smaller and more uni-formly distributed particle size compared to conventional heating (e.g., oil bath). Numerical simulation can help to obtain a better insight into the process in terms of temperature distribution or to evidence existing different temperature profiles and heating rates between the two techniques. In this paper multi-physics numerical simulation is used to investigate the continuous flow synthesis of titanium oxide nanoparticles starting from alkoxide precursors. Temperature-dependent permit-tivity of reactants has been measured, including the effects of permanence at the maximum synthesis temperature. A temperature homogeneity index has been defined to compare microwave and conventional heating. Results show that when using microwave heating at 2450 MHz, in the inves-tigated conditions, a much higher temperature homogeneity of the reactants is reached. Moreover, reactants experience different heating rates, depending on their position inside the microwave ap-plicator, while this is almost negligible in the case of conventional heating

Levulinic acid production from the green macroalgae chaetomorpha linum and valonia aegagropila harvested in the orbetello lagoon

In recent years, the replacement of fossil resources with renewable ones has received great interest, especially as regards the production of new valuable bio-products and bio-fuels, in order to replace the traditional petroleum-based ones. In this context, the exploitation of waste biomasses into added-value biochemicals is strongly encouraged. Among these ones, the algae ones are attracting considerable attention, in particular macroalgae which cause eutrophication problems in estuaries and lagoons, due to the drastic reduction of dissolved oxygen during their decomposition. This is true for Orbetello lagoon (Italy), where a large amount of algal biomasses is removed every year through an expensive practice, with consequent environmentally serious disposal problems. In this work, for the first time, the acid-catalyzed conversion of two different macroalgae harvested in Orbetello lagoon, Chaetomorpha linum (Muller) Kutzing and Valonia aegagropila C. Agardh, into levulinic acid was studied and optimized, adopting a one-pot hydrothermal treatment, under microwave heating and in the presence of aqueous diluted mineral acids, H2SO4 and HCl. Levulinic acid is a versatile platform chemical, classified by the United States Department of Energy as one of the top-12 promising bio-based building blocks. The effect of the main reaction parameters to give levulinic acid was investigated and discussed, in particular the type and concentration of the acid catalyst, the temperature and the reaction time. The highest levulinic acid yields of 19 wt% for Chaetomorpha linum and 16 wt% for Valonia aegagropila, calculated respect to the weight of the starting dried biomass, were reached. The achieved results are very promising and confirm the significant potential of these green algae as renewable starting feedstocks for levulinic acid production

Pathways of 4-hydroxy-2-nonenal detoxification in a human astrocytoma cell line

One of the consequences of the increased level of oxidative stress that often characterizes the cancer cell environment is the abnormal generation of lipid peroxidation products, above all 4-hydroxynonenal. The contribution of this aldehyde to the pathogenesis of several diseases is well known. In this study, we characterized the ADF astrocytoma cell line both in terms of its pattern of enzymatic activities devoted to 4-hydroxynonenal removal and its resistance to oxidative stress induced by exposure to hydrogen peroxide. A comparison with lens cell lines, which, due to the ocular function, are normally exposed to oxidative conditions is reported. Our results show that, overall, ADF cells counteract oxidative stress conditions better than normal cells, thus confirming the redox adaptation demonstrated for several cancer cells. In addition, the markedly high level of NADP+-dependent dehydrogenase activity acting on the glutahionyl-hydroxynonanal adduct detected in ADF cells may promote, at the same time, the detoxification and recovery of cell-reducing power in these cells

Efficacy and safety of levetiracetam in infants and young children with refractory epilepsy

SummaryThe aim of this multicentric, retrospective, and uncontrolled study was to evaluate the efficacy and safety of levetiracetam (LEV) in 81 children younger than 4 years with refractory epilepsy. At an average follow-up period of 9 months, LEV administration was found to be effective in 30% of patients (responders showing more than a 50% decrease in seizure frequency) of whom 10 (12%) became seizure free. This efficacy was observed for focal (46%) as well as for generalized seizures (42%). In addition, in a group of 48 patients, we compared the initial efficacy (evaluated at an average of 3 months of follow-up) and the retention at a mean of 12 months of LEV, with regard to loss of efficacy (defined as the return to the baseline seizure frequency). Twenty-two patients (46%) were initial responders. After a minimum of 12 months of follow-up, 9 of 48 patients (19%) maintained the improvement, 4 (8%) of whom remained seizure free. A loss of efficacy was observed in 13 of the initial responders (59%). Maintained LEV efficacy was noted in patients with focal epilepsy and West syndrome. LEV was well tolerated. Adverse events were seen in 18 (34%) patients. The main side effects were drowsiness and nervousness. Adverse events were either tolerable or resolved in time with dosage reduction or discontinuation of the drug.We conclude that LEV is safe and effective for a wide range of epileptic seizures and epilepsy syndromes and, therefore, represents a valid therapeutic option in infants and young children affected by epilepsy