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

Trust behind bars: Measuring change in inmates' prosocial preferences

The paper presents the results of a Longitudinal Lab-in-the-Field Experiment implemented between September 2015 and July 2016 performed in two State Prisons in California (USA) to measure change in prosocial preferences. A subset of eligible inmates willing to undertake GRIP (Guiding Rage Into Power) program, were randomly assigned to it. The paper tests whether the participation to this program (used as a treatment in the experiments) affects prosocial preferences of participants, with specific reference to trust. The results of a Difference-in-Differences (DID) estimation procedure show that trust significantly increased in GRIP participants compared to the control group. This result is robust to alternative estimation techniques and to the inclusion of an endogenous behavioral measure of altruism

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

Sorghum used to fodder production in dry farming

In Italy water deficient increase forward to cultivate resistant crops for forage production. In the present research it has been studied the opportunity of using 2 varieties of sorghum: the "Sweet Creek", used as green forage and for silage and the "True", with thinner stalks, used as hay. The fodder production and the dhurrin content during the vegetative phase of the 2 varieties were recorded. Production and chemical characteristics of green and preserved fodders (hay and silage) were determined; moreover the nutritive value and the in vitro digestibility of DM were measured. Results confirm the good adaptation of the sorghum to the water limited conditions as those ones in which the test has been carried out; green and preserved fodders yield were high, however during the hay harvest problems due to the different drying dynamics of leaves and stalks were found. The dhurrin content of these two varieties, even in the young phase, allows the use for grazing of the regrown, which have good bunching

In Search of Differential Inhibitors of Aldose Reductase

Aldose reductase, classified within the aldo-keto reductase family as AKR1B1, is an NADPH dependent enzyme that catalyzes the reduction of hydrophilic as well as hydrophobic aldehydes. AKR1B1 is the first enzyme of the so-called polyol pathway that allows the conversion of glucose into sorbitol, which in turn is oxidized to fructose by sorbitol dehydrogenase. The activation of the polyol pathway in hyperglycemic conditions is generally accepted as the event that is responsible for a series of long-term complications of diabetes such as retinopathy, cataract, nephropathy and neuropathy. The role of AKR1B1 in the onset of diabetic complications has made this enzyme the target for the development of molecules capable of inhibiting its activity. Virtually all synthesized compounds have so far failed as drugs for the treatment of diabetic complications. This failure may be partly due to the ability of AKR1B1 to reduce alkenals and alkanals, produced in oxidative stress conditions, thus acting as a detoxifying agent. In recent years we have proposed an alternative approach to the inhibition of AKR1B1, suggesting the possibility of a differential inhibition of the enzyme through molecules able to preferentially inhibit the reduction of either hydrophilic or hydrophobic substrates. The rationale and examples of this new generation of aldose reductase differential inhibitors (ARDIs) are presented

Multimode photonic molecules for advanced force sensing

We propose a force sensor, with optical detection, based on a reconfigurable multicavity photonic molecule distributed over two parallel photonic crystal membranes. The system spectral behaviour is described with an analytical model based on coupled mode theory and validated by finite difference time domain simulations. The deformation of the upper photonic crystal membrane, due to a localized vertical force, is monitored by the relative spectral positions of the photonic molecule resonances. The proposed system can act both as force sensor, with pico-newton sensitivity, able to identify the position where the force is applied, and as torque sensor able to measure the torsion of the membrane along two perpendicular directions

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

Experimental study of the delayed threshold phenomenon in a semiconductor laser

An experimental study of the delayed threshold phenomenon in a Vertical Extended Cavity Semiconductor Emitting Laser is carried out. Under modulation of the pump power, the laser intensity exhibits a hysteresis behavior in the vicinity of the threshold. The temporal width of this hysteresis is measured as a function of the modulation frequency, and is proved to follow the predicted scaling law. A model based on the rate equations is derived and used to analyze the experimental observations. A frequency variation of the laser around the delayed threshold and induced by the phase-amplitude coupling is predicted and estimated