4,379 research outputs found

    Accuracy improvement in the TDR-based localization of water leaks

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    A time domain reflectometry (TDR)-based system for the localization of water leaks has been recently developed by the authors. This system, which employs wire-like sensing elements to be installed along the underground pipes, has proven immune to the limitations that affect the traditional, acoustic leak-detection systems. Starting from the positive results obtained thus far, in this work, an improvement of this TDR-based system is proposed. More specifically, the possibility of employing a low-cost, water-absorbing sponge to be placed around the sensing element for enhancing the accuracy in the localization of the leak is addressed. To this purpose, laboratory experiments were carried out mimicking a water leakage condition, and two sensing elements (one embedded in a sponge and one without sponge) were comparatively used to identify the position of the leak through TDR measurements. Results showed that, thanks to the water retention capability of the sponge (which maintains the leaked water more localized), the sensing element embedded in the sponge leads to a higher accuracy in the evaluation of the position of the leak

    Bioactive potential of two marine picocyanobacteria belonging to Cyanobium and Synechococcus genera

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    Coccoid cyanobacteria produce a great variety of secondary metabolites, which may have useful properties, such as antibacterial, antiviral, anticoagulant or anticancer activities. These cyanobacterial metabolites have high ecological significance, and they could be considered responsible for the widespread occurrence of these microorganisms. Considering the great benefit derived from the identification of competent cyanobacteria for the extraction of bioactive compounds, two strains of picocyanobacteria (coccoid cyanobacteria < 3 µm) (Cyanobium sp. ITAC108 and Synechococ-cus sp. ITAC107) isolated from the Mediterranean sponge Petrosia ficiformis were analyzed. The biological effects of organic and aqueous extracts from these picocyanobacteria toward the nauplii of Artemia salina, sea urchin embryos and human cancer lines (HeLa cells) were evaluated. Methanolic and aqueous extracts from the two strains strongly inhibited larval development; on the contrary, in ethyl acetate and hexane extracts, the percentage of anomalous embryos was low. Moreover, all the extracts of the two strains inhibited HeLa cell proliferation, but methanol extracts exerted the highest activity. Gas chromatography–mass spectrometry analysis evidenced for the first time the presence of β-N-methylamino-L-alanine and microcystin in these picocyanobacteria. The strong cytotoxic activity observed for aqueous and methanolic extracts of these two cyanobacteria laid the foundation for the production of bioactive compounds of pharmacological interest

    Cinema in times of the pandemic COVID: movies helping to moderate emotions and supporting the health team

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    The current COVID-19 pandemic emerges the need of taking care of the health team, not only physical, but also mental health. The crisis we are experiencing has a twofold component: on the one hand the biological threat and on the other to deal with anxiety, fear, and disordered emotions, which are a threat to mental balance and to maintain the serenity necessary to cope with such a great challenge. It is crucial to raise the morale of those who deal daily with this threat of unprecedented proportions. A discouraged doctor is an element of the crisis and causes insecurity in patients and families. SOBRAMFA - Medical Education and Humanism, has disseminated recommendations through short videos for helping professionals to maintain an objective view of the reality they are experiencing. Using cinema through movie clips from different films helps to clarify details of the commented recommendations. Sense of community, leadership, teamwork, holding the emotions on realistic basis, communication skills, educating through example, professionalism, objectivity and realism for redeeming the circumstances are the topics emphasized by the movie clips. Below we list some of the ethical and existential dilemmas as well as the corresponding movie scenes that can help with decisions.La actual pandemia de COVID-19 coloca la necesidad de cuidar del equipo de salud, no solo física, sino también mentalmente. La crisis que estamos viviendo tiene un doble componente: por un lado, la amenaza biológica y, por otro, lidiar con la ansiedad, el miedo y las emociones desordenadas, que son una amenaza para el equilibrio mental y para mantener la serenidad necesaria para hacer frente a tan gran reto. Es crucial elevar la moral de quienes se enfrentan a diario con esta amenaza de proporciones sin precedentes. Un médico desanimado es un elemento de crisis y causa inseguridad en pacientes y familias. SOBRAMFA - Educación médica y humanismo, ha difundido recomendaciones a través de videos cortos para ayudar a los profesionales a mantener una visión objetiva de la realidad que están experimentando. El uso del cine a través de escenas de diferentes películas ayuda a aclarar los detalles de las recomendaciones comentadas. Sentido de comunidad, liderazgo, trabajo en equipo, mantener las emociones de forma realista, habilidades de comunicación, educación a través del ejemplo, profesionalismo, objetividad y realismo para redimir las circunstancias son los temas enfatizados por los clips de películas. A continuación, enumeramos algunos de los dilemas éticos y existenciales, así como las escenas de películas correspondientes que pueden ayudar con las decisiones

    A Study of the B-V Colour Temperature Relation

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    We attempt to construct a B-V colour temperature relation for stars in the least model dependent way employing the best modern data. The fit we obtained with the form Teff = Teff((B-V)0,[Fe/H],log g) is well constrained and a number of tests show the consistency of the procedures for the fit. Our relation covers from F0 to K5 stars with metallicity [Fe/H] = -1.5 to +0.3 for both dwarfs and giants. The residual of the fit is 66 K, which is consistent with what are expected from the quality of the present data. Metallicity and surface gravity effects are well separated from the colour dependence. Dwarfs and giants match well in a single family of fit, differing only in log g. The fit also detects the Galactic extinction correction for nearby stars with the amount E(B-V) = 0.26 +/-0.03 mag/kpc. Taking the newly obtained relation as a reference we examine a number of B-V colour temperature relations and atmosphere models available in the literature. We show the presence of a systematic error in the colour temperature relation from synthetic calculations of model atmospheres; the systematic error across K0 to K5 dwarfs is 0.04-0.05 mag in B-V, which means 0.25-0.3 mag in Mv for the K star range. We also argue for the error in the temperature scale used in currently popular stellar population synthesis models; synthetic colours from these models are somewhat too blue for aged elliptical galaxies. We derive the colour index of the sun (B-V)sun = 0.627 +/-0.018, and discuss that redder colours (e.g., 0.66-0.67) often quoted in the literature are incompatible with the colour-temperature relation.Comment: AASLaTeX (aaspp4.sty),36 pages (13 figures included), submitted to Astronomical Journal, replaced (typo in author name

    The Neuropsychological Profile of Attention Deficits of Patients with Obstructive Sleep Apnea: An Update on the Daytime Attentional Impairment

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    none7noAbstract: Introduction: Patients with obstructive sleep apnea (OSA) suffer from several neurocognitive disturbances. One of the neuropsychological processes most investigated in OSA patients is attention, but the results have been controversial. Here, we update the attention profile of OSA patients with the final aim to improve attention assessment, with a possible impact on clinical and medical-legal practices, in terms of which attention subdomains and parameters need consideration and which one is a high-risk OSA phenotype for attention dysfunctions. Method: For this purpose, we assessed 32 previously untreated OSA patients (26 men and 6 women) under 65 years of age (mean age 53.2 ± 7.3; mean education level 10.4 ± 3.4 years) suffering from moderate to severe sleep apnea and hypopnea (mean apnea-hypopnea index (AHI) 45.3 ± 22.9, range 16.1–69.6). A control group of 34 healthy participants matched with OSA patients for age, education level, and general cognitive functioning were also enrolled. The OSA patients and healthy participants were tested through an extensive computerized battery (Test of Attentional Performance, TAP) that evaluated intensive (i.e., alertness and vigilance) and selective (i.e., divided and selective) dimensions of attention and returned different outcome parameters (i.e., reaction time, stability of performance, and various types of errors). Data analysis: The data were analyzed by ANCOVA which compared the speed and accuracy performance of the OSA and control participants (cognitive reserve was treated as a covariate). The possible mechanisms underlying attention deficits in OSA patients were examined through correlation analysis among AHI, oxygenation parameters, sleepiness scores, and TAP outcomes and by comparing the following three phenotypes of patients: severe OSA and severe nocturnal desaturators (AHI++D+), severe OSA nondesaturators (AHI++D−), and moderate OSA nondesaturators (AHI+D−). Results: The results suggest that the OSA patients manifest deficits in both intensive and selective attention processes and that reaction time (RT) alone is ineffective for detecting and characterizing their problems, for which error analysis and stability of performance also have to be considered. Patients with severe OSA and severe hypoxemia underperformed on alertness and vigilance attention subtests. Conclusions: The data suggest the importance of evaluating attention deficits among OSA patients through several parameters (including performance instability). Moreover, the data suggest a multifaceted mechanism underlying attention dysfunction in OSA patients.openAngelelli P., Macchitella L., Toraldo D.M., Abbate E., Marinelli C.V., Ariglian M., De Benedetto M.Angelelli, P.; Macchitella, L.; Toraldo, D. M.; Abbate, E.; Marinelli, C. V.; Ariglian, M.; De Benedetto, M

    The GEMAS Project: Geochemistry of European agricultural and grazing land soils.

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    Viene illustrato il progetto GEMAS che ha interessato la campionatura e le analisi di suoli dell'ntero continente Europeo da parte dei Servizi Geologici d'Europa, nell'ìambito delle attività dell'EuroGeoSurvey

    Symptomatic carotid atherosclerotic plaques are associated with increased infiltration of natural killer (NK) cells and higher serum levels of NK activating receptor ligands

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    A wide array of immune cells, including lymphocytes, is known to be present and to play a pathogenetic role in atherosclerotic lesions. However, limited information is currently available regarding the presence of Natural Killer (NF cell subsets within vessel plaque, and more in general, regarding their role in human atherosclerosis. We evaluated the distribution of NK cells in human carotid atherosclerotic plaques, dissecting asymptomatic and symptomatic patients (identified as affected by stroke, transient ischemic attack, or amaurosis fugax within 6 months) with the aim of shedding light on the putative contribution of NK cells to the pathogenic process that leads to plaque instability and subsequent clinical complications. We observed that carotid plaques were consistently infiltrated by NK cells and, among them, CD56(bright)perforin(low) NK cells were abundantly present and displayed different markers of tissue residency (i.e., CD103 CD69 and CD49a). Interestingly, carotid atherosclerotic plaques of symptomatic patients showed a higher content of NK cells and an increased ratio between CD56(bright)perforin(low) NK cells and their CD56(dim)perforin(high)counterpart. NK cells isolated from plaques of symptomatic patients were also stronger producers of IFN-gamma. Analysis of the expression of NK activating receptor ligands (including MICA/B, ULBP-3, and B7-H6) in atherosclerotic carotid plaques revealed that they were abundantly expressed by a HLA-DR(+)CD11c(+) myeloid cell population resident in the plaques. Remarkably, sera of symptomatic patients contained significant higher levels of soluble ligands for NK activating receptors. Our observations indicate that CD56(bright)( )NK cells accumulate within human atherosclerotic lesions and suggest a possible contribution of NK cells to the process determining plaque instability

    Ergodicity criteria for non-expanding transformations of 2-adic spheres

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    In the paper, we obtain necessary and sufficient conditions for ergodicity (with respect to the normalized Haar measure) of discrete dynamical systems on 2-adic spheres S2r(a)\mathbf S_{2^{-r}}(a) of radius 2r2^{-r}, r1r\ge 1, centered at some point aa from the ultrametric space of 2-adic integers Z2\mathbb Z_2. The map f ⁣:Z2Z2f\colon\mathbb Z_2\to\mathbb Z_2 is assumed to be non-expanding and measure-preserving; that is, ff satisfies a Lipschitz condition with a constant 1 with respect to the 2-adic metric, and ff preserves a natural probability measure on Z2\mathbb Z_2, the Haar measure μ2\mu_2 on Z2\mathbb Z_2 which is normalized so that μ2(Z2)=1\mu_2(\mathbb Z_2)=1

    Interplay between non-coding rna transcription, stringent/relaxed phenotype and antibiotic production in streptomyces ambofaciens

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    While in recent years the key role of non-coding RNAs (ncRNAs) in the regulation of gene expression has become increasingly evident, their interaction with the global regulatory circuits is still obscure. Here we analyzed the structure and organization of the transcriptome of Streptomyces ambofaciens, the producer of spiramycin. We identified ncRNAs including 45 small-RNAs (sRNAs) and 119 antisense-RNAs (asRNAs I) that appear transcribed from dedicated promoters. Some sRNAs and asRNAs are unprecedented in Streptomyces and were predicted to target mRNAs encoding proteins involved in transcription, translation, ribosomal structure and biogenesis, and regulation of morphological and biochemical differentiation. We then compared ncRNA expression in three strains: (i) the wild-type strain; (ii) an isogenic pirA-defective mutant with central carbon metabolism imbalance, “relaxed” phenotype, and repression of antibiotic production; and (iii) a pirA-derivative strain harboring a “stringent” RNA polymerase that suppresses pirA-associated phenotypes. Data indicated that the expression of most ncRNAs was correlated to the stringent/relaxed phenotype suggesting novel effector mechanisms of the stringent response
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