3,887 research outputs found

    The Casimir Energy in Curved Space and its Supersymmetric Counterpart

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    We study dd-dimensional Conformal Field Theories (CFTs) on the cylinder, Sd−1×RS^{d-1}\times \mathbb{R}, and its deformations. In d=2d=2 the Casimir energy (i.e. the vacuum energy) is universal and is related to the central charge cc. In d=4d=4 the vacuum energy depends on the regularization scheme and has no intrinsic value. We show that this property extends to infinitesimally deformed cylinders and support this conclusion with a holographic check. However, for N=1\mathcal{N}=1 supersymmetric CFTs, a natural analog of the Casimir energy turns out to be scheme independent and thus intrinsic. We give two proofs of this result. We compute the Casimir energy for such theories by reducing to a problem in supersymmetric quantum mechanics. For the round cylinder the vacuum energy is proportional to a+3ca+3c. We also compute the dependence of the Casimir energy on the squashing parameter of the cylinder. Finally, we revisit the problem of supersymmetric regularization of the path integral on Hopf surfaces.Comment: 53 pages; v2: minor changes, references added, version published in JHE

    Drosophila CG3303 is an essential endoribonuclease linked to TDP-43-mediated neurodegeneration

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    Endoribonucleases participate in almost every step of eukaryotic RNA metabolism, acting either as degradative or biosynthetic enzymes. We previously identified the founding member of the Eukaryotic EndoU ribonuclease family, whose components display unique biochemical features and are flexibly involved in important biological processes, such as ribosome biogenesis, tumorigenesis and viral replication. Here we report the discovery of the CG3303 gene product, which we named DendoU, as a novel family member in Drosophila. Functional characterisation revealed that DendoU is essential for Drosophila viability and nervous system activity. Pan-neuronal silencing of dendoU resulted in fly immature phenotypes, highly reduced lifespan and dramatic motor performance defects. Neuron-subtype selective silencing showed that DendoU is particularly important in cholinergic circuits. At the molecular level, we unveiled that DendoU is a positive regulator of the neurodegeneration-associated protein dTDP-43, whose downregulation recapitulates the ensemble of dendoU-dependent phenotypes. This interdisciplinary work, which comprehends in silico, in vitro and in vivo studies, unveils a relevant role for DendoU in Drosophila nervous system physio-pathology and highlights that DendoU-mediated neurotoxicity is, at least in part, contributed by dTDP-43 loss-of-function

    Neurophysiological Profile of Antismoking Campaigns

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    Over the past few decades, antismoking public service announcements (PSAs) have been used by governments to promote healthy behaviours in citizens, for instance, against drinking before the drive and against smoke. Effectiveness of such PSAs has been suggested especially for young persons. By now, PSAs efficacy is still mainly assessed through traditional methods (questionnaires and metrics) and could be performed only after the PSAs broadcasting, leading to waste of economic resources and time in the case of Ineffective PSAs. One possible countermeasure to such ineffective use of PSAs could be promoted by the evaluation of the cerebral reaction to the PSA of particular segments of population (e.g., old, young, and heavy smokers). In addition, it is crucial to gather such cerebral activity in front of PSAs that have been assessed to be effective against smoke (Effective PSAs), comparing results to the cerebral reactions to PSAs that have been certified to be not effective (Ineffective PSAs). &e eventual differences between the cerebral responses toward the two PSA groups will provide crucial information about the possible outcome of new PSAs before to its broadcasting. &is study focused on adult population, by investigating the cerebral reaction to the vision of different PSA images, which have already been shown to be Effective and Ineffective for the promotion of an antismoking behaviour. Results showed how variables as gender and smoking habits can influence the perception of PSA images, and how different communication styles of the antismoking campaigns could facilitate the comprehension of PSA’s message and then enhance the related impac

    “Io e la matematica”: un’indagine sull’esperienza matematica

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    Scopo di questo articolo ù quello di esaminare il rap- porto delle persone con la matematica e il suo insegnamento. Attraverso la somministrazione di un questionario online (domande con risposta libera testuale) viene chiesto ai parte- cipanti di indicare in particolare le emozioni associate alla matematica e la propria esperienza con essa. I risultati della survey sono analizzati mediante tecniche statistiche di Natural Language Processing, tra tutte la Sentiment Analysis e il POS Tagging. Viene studiata la dipendenza delle emozioni riguardanti la matematica dal livello e tipologia di istruzione dei partecipanti all’indagine; in particolare viene posta l’attenzione sulle principali critiche al metodo di insegnamento emerse tra i giovani

    Neurophysiological Responses to Different Product Experiences

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    It is well known that the evaluation of a product from the shelf considers the simultaneous cerebral and emotional evaluation of the different qualities of the product such as its colour, the eventual images shown, and the envelope’s texture (hereafter all included in the term “product experience”). However, the measurement of cerebral and emotional reactions during the interaction with food products has not been investigated in depth in specialized literature. (e aim of this paper was to investigate such reactions by the EEG and the autonomic activities, as elicited by the cross-sensory interaction (sight and touch) across several different products. In addition, we investigated whether (i) the brand (Major Brand or Private Label), (ii) the familiarity (Foreign or Local Brand), and (iii) the hedonic value of products (Comfort Food or Daily Food) influenced the reaction of a group of volunteers during their interaction with the products. Results showed statistically significantly higher tendency of cerebral approach (as indexed by EEG frontal alpha asymmetry) in response to comfort food during the visual exploration and the visual and tactile exploration phases. Furthermore, for the same index, a higher tendency of approach has been found toward foreign food products in comparison with local food products during the visual and tactile exploration phase. Finally, the same comparison performed on a different index (EEG frontal theta) showed higher mental effort during the interaction with foreign products during the visual exploration and the visual and tactile exploration phases. Results from the present study could deepen the knowledge on the neurophysiological response to food products characterized by different nature in terms of hedonic value familiarity; moreover, they could have implications for food marketers and finally lead to further study on how people make food choices through the interactions with their commercial envelope

    Diagnostic Accuracy of a New Antigen Test for SARS-CoV-2 Detection

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    Background and aims: Quick and reliable diagnostic tools play an important role in controlling the spread of the SARS-Cov-2 pandemic. The aim of this study was to evaluate the diagnostic accuracy of a new cyto-salivary antigen test aimed at detecting the presence of antigens for SARS-CoV-2, as compared by the gold standard RT-PCR and a lateral flow test. Methods: A total of 433 healthy volunteers were enrolled in the study and the sensitivity and specificity of the new cyto-salivary antigen test were calculated, as compared to the RT-PCR nasopharyngeal swab and to the lateral flow test. Results: A total of 433 samples were collected and tested at the Mediterranean Fair in Palermo from February 2021 until April 2021. The new cyto-salivary antigen had a sensitivity of 100% and a specificity of 94.2%. The sensitivity and the specificity of the lateral flow test were 55% and 100%, respectively. Conclusions: The new cyto-salivary antigen test detected more positive cases than the RT-PCR in a sample of asymptomatic subjects, demonstrating to be a promising tool for a more sensitive diagnosis of COVID-19. Further studies are warranted to better characterize its diagnostic accuracy

    Eating episode frequency and fruit and vegetable consumption among Italian university students

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    Objective: To analyze breakfast consumption, regularity of meals, fruit and vegetable consumption in the Italian University Student population on a national level.Design: Descriptive analysis evaluating data taken from the “Sportello Salute Giovani” questionnaire.Participants: 12.000 university students who self-administered a confidential survey. 8292 questionnaires were analyzed.Variables measured: Age; sex; self-reported economic status; BMI; number of breakfast and portions of vegetables and portions of fruit usually consumed per week; number of eating episodes per day; intended weight loss.Analysis: Descriptive and logistic regression analyses were conducted. Gender and age differences were tested by Chi2 and Mann-Whitney tests.Results: 15.8% of males and 26.3% of females declared to consume at least one portion of fruit every day. Similar results were found for vegetable consumption. Age does not influence fruit or vegetables consumption, frequency of eating episodes or breakfast habit. Both a regular breakfast and a higher number of eating episodes are significantly associated both with a higher frequency of fruit and vegetables intake.Conclusions and implications: This study underlines the need to promote nutritional education campaigns to increase adherence to nutritional guidelines

    Study of Holtermanniella wattica, Leucosporidium creatinivorum, Naganishia adeliensis, Solicoccozyma aeria, and Solicoccozyma terricola for their lipogenic aptitude from different carbon sources

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    Background The ability of some microorganisms to accumulate lipids is well known; however, only recently the number of studies on microbial lipid biosynthesis for obtaining oleochemical products, namely biofuels and some building blocks for chemistry, is rapidly and spectacularly increased. Since 1990s, some oleaginous yeasts were studied for their ability to accumulate lipids up to 60\u201370% of their dry weight. Due to the vast array of engineering techniques currently available, the recombinant DNA technology was the main approach followed so far for obtaining lipid-overproducing yeasts, mainly belonging to the Yarrowia lipolytica. However, an alternative approach can be offered by worldwide diversity as source of novel oleaginous yeasts. Lipogenic aptitude of a number of yeast strains has been reviewed, but many of these studies utilized a limited number of species and/or different culture conditions that make impossible the comparison of different results. Accordingly, the lipogenic aptitude inside the yeast world is still far from being fully explored, and finding new oleaginous yeast species can acquire a strategic importance. Results Holtermanniella wattica, Leucosporidium creatinivorum, Naganishia adeliensis, Solicoccozyma aeria, and Solicoccozyma terricola strains were selected as a result of a large-scale screening on 706 yeasts (both Ascomycota and Basidiomycota). Lipid yields and fatty acid profiles of selected strains were evaluated at 20 and 25 \ub0C on glucose, and on glycerol, xylose, galactose, sucrose, maltose, and cellobiose. A variable fatty acid profile was observed in dependence of both temperature and different carbon sources. On the whole, L. creatinivorum exhibited the highest performances: total lipid yield (YL) >7 g/l on glucose and glycerol, % of intracellular lipids on cell biomass (YL/DW) >70% at 20 \ub0C on glucose, lipid coefficient (YL/Glu) around 20% on glucose, and daily productivity (YL/d) on glucose and sucrose >1.6 g/(l*d). Conclusions This study provides some meaningful information about the lipogenic ability of some yeast species. Variable lipid yields and fatty acid profiles were observed in dependence of both temperature and different carbon sources. L. creatinivorum exhibited the highest lipogenic performances
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