2,871 research outputs found

    A Preliminary 1D-3D Analysis of the Darmstadt Research Engine under Motored Condition

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    In the present paper, 1D and 3D CFD models of the Darmstadt research engine undergo a preliminary validation against the available experimental dataset at motored condition. The Darmstadt engine is a single-cylinder optical research unit and the chosen operating point is characterized by a revving speed equal to 800 rpm with intake temperature and pressure of 24 \ub0C and 0.95 bar, respectively. Experimental data are available from the TU Darmstadt engine research group. Several aspects of the engine are analyzed, such as crevice modeling, blow-by, heat transfer and compression ratio, with the aim to minimize numerical uncertainties. On the one hand, a GT-Power model of the engine is used to investigate the impact of blow-by and crevices modeling during compression and expansion strokes. Moreover, it provides boundary conditions for the following 3D CFD simulations. On the other hand, the latter, carried out in a RANS framework with both highand low-Reynolds wall treatments, allow a deeper investigation of the boundary layer phenomena and, thus, of the gas-to-wall heat transfer. A detailed modeling of the crevice, along with an ad hoc tuning of both blow-by and heat fluxes lead to a remarkable improvement of the results. However, in order to adequately match the experimental mean in-cylinder pressure, a slight modification of the compression ratio from the nominal value is accounted for, based on the uncertainty which usually characterizes such geometrical parameter. The present preliminary study aims at providing reliable numerical setups for 1D and 3D models to be adopted in future detailed investigations on the Darmstadt research engine

    Aumento da sustentabilidade da produção de raças suínas locais através do uso de rótulos de qualidade - Estudo de caso e desenvolvimento de uma marca comercial no projecto TREASURE

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    The interest for traditional genetic resources, here comprised local pig breeds, has been increased in the last decades. Yet, at the time being, majority of local pig breeds still need to be supported with subsidies to ensure their conservation. However, the best strategy is if breeds could reach self-sustainability which is possible by an efficient marketing strategy of their products. The majority of studied breeds in project TREASURE are untapped, so the ambition is to develop an “umbrella” collective trademark that would gather together all breeds and that would create added values for their products. Major socio-economic aspects related to the implementation of the collective trademark include rights, responsibilities and expected added value for end-users. Based on the results obtained by an internal survey conducted in TREASURE, we have identified the main features of the collaborative trademark: 1) it should attract end-users such as farmers, breeders associations and meat processors; 2) it should be developed and promoted by an operational committee of end-users, under the coordination and supervision of TREASURE Consortium; 3) it should emphasize local pig genetic resources as the key common point, considering also production systems and nutrition; 4) it should explore possible collaboration or conflict with existing EU protected products (PDO, PGI, TSG) in order to optimally promote local products. An overview of intellectual property rights (IPR) in the context of pork value chains existing in the European Union is presented and prospects for TREASURE trademark analysed

    PANI-Based Stacked Ferromagnetic Systems: Electrochemical Preparation and Characterization

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    In this work, the electropolymerization of polyaniline (PANI) is explored for its action as either a suitable coating or as a substrate for Nickel (Ni) and Magnetite (Fe3O4) surfaces. PANI electropolymerization has been achieved through cyclic voltammetry (CV), potentiostatic and galvanostatic electrochemical methods. The interaction between the obtained surfaces and the ferromagnetic layers (Ni and Fe3O4) has been investigated as a function of the pH of the electrolytic PANI solution, and also a variety of experimental parameters have been optimized in order to achieve the synthesis of PANI coatings (solvent, substrate, concentrations, and cell set-up). Thus, we obtained stable and consistent PANI thick films at the interface of both the nickel and the magnetite ferromagnetic materials

    Low-Cost Potentiometric Sensor for Chloride Measurement in Continuous Industrial Process Control

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    Recently, the new updates in legislation about drinking water control and human health have increased the demand for novel electrochemical low-cost sensors, such as potentiometric ones. Nowadays, the determination of chloride ion in aqueous solutions has attracted great attention in several fields, from industrial processes to drinking water control. Indeed, chloride plays a crucial role in corrosion, also influencing the final taste of beverages, especially coffee. The main goal is to obtain devices suitable for continuous and real-time analysis. For these reasons, we investigated the possibility to develop an easy, low-cost potentiometric chloride sensor, able to perform analysis in aqueous mediums for long immersion time and reducing the need of periodic calibration. We realized a chloride ion selective electrode made of Ag/AgCl sintered pellet and we tested its response in model solutions compatible with drinking water. The sensor was able to produce a stable, reproducible, and accurate quantification of chloride in 900 s, without the need for a preliminary calibration test. This opens the route to potential applications of this sensor in continuous, in situ, and real time measurement of chloride ions in industrial processes, with a reduced need for periodic maintenance

    Whole genome semiconductor based sequencing of farmed European sea bass (Dicentrarchus labrax) Mediterranean genetic stocks using a DNA pooling approach

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    European sea bass (Dicentrarchus labrax) is an important marine species for commercial and sport fisheries and aquaculture production. Recently, the European sea bass genome has been sequenced and assembled. This resource can open new opportunities to evaluate and monitor variability and identify variants that could contribute to the adaptation to farming conditions. In this work, two DNA pools constructed from cultivated European sea bass were sequenced using a next generation semiconductor sequencing approach based on Ion Proton sequencer. Using the first draft version of the D. labrax genome as reference, sequenced reads obtained a total of about 1.6 million of single nucleotide polymorphisms (SNPs), spread all over the chromosomes. Transition/transversion (Ti/Tv) was equal to 1.28, comparable to what was already reported in Salmon species. A pilot homozygosity analysis across the D. labrax genome using DNA pool sequence datasets indicated that this approach can identify chromosome regions with putative signatures of selection, including genes involved in ion transport and chloride channel functions, amino acid metabolism and circadian clock and related neurological systems. This is the first study that reported genome wide polymorphisms in a fish species obtained with the Ion Proton sequencer. Moreover, this study provided a methodological approach for selective sweep analysis in this species

    How personality relates to distress in parents during the COVID-19 lockdown: The mediating role of child’s emotional and behavioral difficulties and the moderating effect of living with other people

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    Since the initiation of the COVID-19 lockdown, Italian parents have been forced to manage their children at home. The present study aimed at investigating the psychological distress of parents during the lockdown, identifying contributing factors. An online survey was administered to 833 participants from 3 to 15 April 2020. Mediation and moderated mediation models were run to explore the association between parent neuroticism and parent distress, mediated by child hyperactivity–inattention and child emotional symptoms, and the moderating effect of living only with child(ren) on the direct and indirect effects of parent neuroticism on parent distress. For parents living only with child(ren), high levels of psychological distress depended exclusively on their levels of neuroticism. For parents living with at least one other person in addition to child(ren), distress levels were also mediated by child behavioral and emotional difficulties. Motherhood emerged as a significant factor contributing to greater distress. Furthermore, parent psychological distress decreased in line with increased child age. The results confirm that neuroticism is an important risk factor for mental health. Preventive measures should be primarily target multicomponent families with younger children and directed towards parents who are already known to present emotional instability and to parents of children who have received local mental health assistance for behavioral and/or emotional difficulties

    Sexual Fantasies and Stereotypical Gender Roles: The Influence of Sexual Orientation, Gender and Social Pressure in a Sample of Italian Young-Adults

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    Differences in gender and sexual orientation are suggested to be linked to differences in the way individuals think and behave. The aim of the current study is to evaluate the effect of gender and sexual orientation on sexual fantasies and gender roles in heterosexual and gay and lesbian people. The sample was composed of 547 participants, 246 men (Mage = 28.85; SD = 9,27) and 301 women (Mage = 25,97; SD = 7,141). Within this sample, 61.8% of men and 79.4% of women were heterosexual, whereas 38.2% of men and 20.6% of women were gay and lesbian. Participants completed an online battery of questionnaires to assess their sexual orientation, sexual fantasies, and gender roles on three different dimensions. It was hypothesized that the heterosexual group would report more normative sexual fantasies (H1) and that women in general would report androgynous characteristics, which would be linked to a low degree of reported feminine ideal roles and high social pressure to conform to feminine social expectations (H2). The results showed that lesbian women scored slightly higher than heterosexual women on transgressive sexual fantasies and lower on emotional-romantic ones. Moreover, heterosexual women, but not lesbian women, showed a pattern of high social pressure to conform to feminine expectations together with lower scores in the IRQ. We found the same results on gay men but not for heterosexual men. The overall results suggest that sexual fantasies and gender roles are relatively independent concepts and are influenced by different mechanisms

    Next generation semiconductor based sequencing of the donkey (Equus asinus) genome provided comparative sequence data against the horse genome and a few millions of single nucleotide polymorphisms

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    Few studies investigated the donkey (Equus asinus) at the whole genome level so far. Here, we sequenced the genome of two male donkeys using a next generation semiconductor based sequencing platform (the Ion Proton sequencer) and compared obtained sequence information with the available donkey draft genome (and its Illumina reads from which it was originated) and with the EquCab2.0 assembly of the horse genome. Moreover, the Ion Torrent Personal Genome Analyzer was used to sequence reduced representation libraries (RRL) obtained from a DNA pool including donkeys of different breeds (Grigio Siciliano, Ragusano and Martina Franca). The number of next generation sequencing reads aligned with the EquCab2.0 horse genome was larger than those aligned with the draft donkey genome. This was due to the larger N50 for contigs and scaffolds of the horse genome. Nucleotide divergence between E. caballus and E. asinus was estimated to be similar to 0.52-0.57%. Regions with low nucleotide divergence were identified in several autosomal chromosomes and in the whole chromosome X. These regions might be evolutionally important in equids. Comparing Y-chromosome regions we identified variants that could be useful to track donkey paternal lineages. Moreover, about 4.8 million of single nucleotide polymorphisms (SNPs) in the donkey genome were identified and annotated combining sequencing data from Ion Proton (whole genome sequencing) and Ion Torrent (RRL) runs with Illumina reads. A higher density of SNPs was present in regions homologous to horse chromosome 12, in which several studies reported a high frequency of copy number variants. The SNPs we identified constitute a first resource useful to describe variability at the population genomic level in E. asinus and to establish monitoring systems for the conservation of donkey genetic resources
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