2,194 research outputs found

    Nitric Oxide Protects Neuroblastoma Cells from Apoptosis Induced by Serum Deprivation through cAMP-response Element-binding Protein (CREB) Activation

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    The transcription factor cAMP-response element-binding protein (CREB) mediates survival in many cells, including neurons. Recently, death of cerebellar granule neurons due to nitric oxide (NO) deprivation was shown to be accompanied by down-regulation of CREB activity (1). We now provide evidence that overproduction of endogenous NO or supplementation with exogenous NO renders SK-N-BE human neuroblastoma cells more resistant to apoptosis induced by serum deprivation. Parental cells underwent apoptosis after 24 h of serum deprivation, an outcome largely absent in clones overexpressing human neuronal nitric oxide synthase (nNOS). This protective effect was reversed by the inhibition of NOS itself or soluble guanylyl cyclase, pointing at cGMP as an intermediate effector of NO-mediated rescue. A slow-releasing NO donor protected parental cells to a significant extent, thus confirming the survival effect of NO. The impaired viability of serum-deprived parental cells was accompanied by a strong decrease of CREB phosphorylation and transcriptional activity, effects significantly attenuated in nNOS-overexpressing clones. To confirm the role of CREB in survival, the ectopic expression of CREB and/or protein kinase A largely counteracted serum deprivation-induced cell death of SK-N-BE cells, whereas transfection with a CREB negative mutant was ineffective. These experiments indicate that CREB activity is an important step for NO-mediated survival in neuronal cells

    A comparison between different methods to fill gaps in early precipitation series

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    The aim of this work is to analyse and compare different methodologies to fill gaps in early precipitation series, and to evaluate which time resolution is reachable, i.e. monthly or daily one. The following methods are applied and tested to fill the 1764–1767 gap in the precipitation series of Padua: (1) using a relationship between monthly amounts and frequencies; (2) transforming a daily log with visual observations into numerical values through analysis, classification, and calibration; (3) substituting the missing values with an instrumental record from a nearby, contemporary station in the same climatic area. To apply the second method, the descriptions reported in the Morgagni Logs are grouped in 37 classes and transformed into numerical values, using for calibration the observed amounts in the Poleni record over the 24-year common period. As a third method, the series of Temanza and Pollaroli in Venice is used to fill the gap, and the application of a factor scale based on the ratio Padua/Venice tempted. The results of these three methods are discussed and commented

    Three centuries of daily precipitation in Padua, Italy, 1713–2018: history, relocations, gaps, homogeneity and raw data

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    Long instrumental records are fundamental to study climate changes, but their reliability and quality have to be checked before any statistical research. Moreover, when metadata are used to solve some problems, data interpretation may change and require further work to refine the series. A thorough revision of the three-century precipitation series in Padua (1713–2018) shows that the results of previous analyses were affected by serious biases. This paper clarifies key features concerning early instruments, exposure, relocation and observational protocols. The daily analysis pointed out a number of problems, bias, irregular sampling and underestimations that have passed unobserved so far. A comparison with the parallel series of Bologna and Venice made it possible to distinguish bias from the climate signal or to reconstruct missing data. The instrumental threshold was recognized to be fundamental to determine the frequency of precipitation, but less important with respect to its amount. This paper provides a methodological example to test the goodness of long instrumental series, in particular to identify problems related to metadata and observations, which is the preliminary step to perform a sound correction and obtain a reliable series. It also includes the set of original raw data, transformed into modern units

    “A warning from Mars”: effect of microclimate changes at the Specola Museum of Palermo

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    The Specola Museum is located at the Palermo Astronomical Observatory and preserves most of its material heritage. It is part of the Museum System of the University of Palermo (SiMuA) and its management and conservation are entrusted to the INAF - Astronomical Observatory of Palermo. Among the historical instruments on display, there is a 19th-century painted wooden globe reproducing the surface of Mars. It has been on display in a showcase, inside the Merz Telescope Hall, for about 20 years without undergoing any type of intervention or evident deterioration sign. From 2021, in less than two years, damages of its pictorial layers occurred at a progressive rate. The European Standard EN 15757 explains that hygroscopic materials are highly vulnerable to microclimate changes. The wooden globe was in good conditions after two decades of permanence at the museum, but the recent control and management of the indoor climate was not compatible with the past climate history of the globe to which it has adapted. The speed of the degradation made it evident that the microclimatic conditions of the room changed abruptly. The warning deduced from the Mars globe deterioration was hence easy to decode: there is something wrong with this climate! It is well known that museum microclimate plays a key role in the conservation of the objects on display. It may trigger or aggravate degradation processes of the materials constituting the object exhibited and affect their “life expectancy”. Moreover, each object responses peculiarly to environment variability, depending on its composition and conservation history. When an artifact is composed of different materials, unexpected synergistic effects may develop. Finding appropriate values range of temperature, relative humidity and illuminance and managing them to guarantee the conservation of the entire collection, and at the same time improving the thermal comfort for people working there, is a difficult task. The issue becomes even more challenging in buildings not originally designed for conservation purposes, as the Specola Museum, located in the ancient observatory rooms, built in 1790 on the top of the 12nd-century Royal Palace. An accurate restoration has been made, and conservation measures have been adopted, to stop the serious deteriorating processes affecting the model of Mars but the risk of further deterioration phenomena involving other objects is expected to increase substantially if no actions are taken. This contribution intends to present the results of the preliminary study concerning the thermo-hygrometric records taken in the Merz Telescope Hall over the last two years and propose specific actions to improve its microclimate conditions. References Carotenuto M. R., Randazzo D., Chinnici I., Genua G., Preventive Conservation Projects on LAM Materials at the INAF-Astronomical Observatory of Palermo “G.S. Vaiana”, Bulletin of the AAS, 54(2) (2022) Carotenuto M. R., Chinnici I. et al., Rapporto tecnico INAF 2022 - Il Museo della Specola: progetti per la conservazione, la fruizione, la comunicazione (2018-2020) Camuffo D., Microclimate for cultural heritage. Measurement, Risk Assessment, Conservation, Restoration, and Maintenance of Indoor and Outdoor Monuments, Elsevier, third Edition (2019) Antomarchi C., Pedersoli Jr., Michalski S., Guide to Risk Management, ICCROM (2016) Foderà Serio G., Chinnici I., L'Osservatorio Astronomico di Palermo, Palermo (1997

    Prevalence of olfactory and other developmental anomalies in patients with central hypogonadotropic hypogonadism

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    Introduction: Hypogonadotropic hypogonadism (HH) is a heterogeneous disease caused by mutations in several genes. Based on the presence of hyposmia/anosmia it is distin- guished into Kallmann syndrome (KS) and isolated HH. The prevalence of other develop- mental anomalies is not well established. Methods: We studied 36 patients with HH (31 males, 5 females, mean age 41.5), 9 with familial and 27 with sporadic HH (33 congenital, 3 adult-onset), by physical examination, smell test (BSIT Sensonics), audiometry, renal ultrasound, and magnetic resonance imag- ing of the olfactory structures. Results: Based on the smell test, patients were classified as normosmic (n = 21, 58.3%) and hypo/anosmic (n = 15, 41.6%). Hypoplasia/agenesis of olfactory bulbs was found in 40% of patients (10/25; 75% hypo/anosmic, 7.6% normosmic, p<0.01, Fisher’s test). Remarkably, olfactory structures were normal in two anosmic patients, while one nor- mosmic patient presented a unilateral hypoplastic bulb. Fourteen of 33 patients (42.4%) presented neurosensorial hearing loss of various degrees (28.5% hypo/anosmic, 52.6% normosmic, p=NS). Renal ultrasound revealed 27.7% of cases with renal anomalies (26.6% hypo/anosmic, 28.5% normosmic, p = NS). At least one midline defect was found in 50% of the patients (53.3% hypo/anosmic, 47.6% normosmic, p = NS), including abnor- mal palate, dental anomalies, pectus excavatum, bimanual synkinesis, iris coloboma, and absent nasal cartilage. Anamnestically 4/31 patients reported cryptorchidism (25% hypo/anosmic, 5.2% normosmic, p = NS). Conclusion: Hypo/anosmia is significantly related to anatomical anomalies of the olfac- tory bulbs/tracts but the prevalence of other developmental anomalies, especially midline defects and neurosensorial hearing loss, is high both in HH and KS and independent of the presence of anosmia/hyposmia. From the clinical standpoint KS and normosmic HH should be considered as the same complex, developmental disease

    Resonant Fully dielectric metasurfaces for ultrafast Terahertz pulse generation

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    Metasurfaces represent a new frontier in materials science paving for unprecedented methods of controlling electromagnetic waves, with a range of applications spanning from sensing to imaging and communications. For pulsed terahertz generation, metasurfaces offer a gateway to tuneable thin emitters that can be utilised for large-area imaging, microscopy and spectroscopy. In literature THz-emitting metasurfaces generally exhibit high absorption, being based either on metals or on semiconductors excited in highly resonant regimes. Here we propose the use of a fully dielectric semiconductor exploiting morphology-mediated resonances and inherent quadratic nonlinear response. Our system exhibits a remarkable 40-fold efficiency enhancement compared to the unpatterned at the peak of the optimised wavelength range, demonstrating its potential as scalable emitter design

    Resonant Fully Dielectric Metasurfaces for Ultrafast Terahertz Pulse Generation

    Get PDF
    Metasurfaces represent a new frontier in materials science paving for unprecedented methods of controlling electromagnetic waves, with a range of applications spanning from sensing to imaging and communications. For pulsed terahertz (THz) generation, metasurfaces offer a gateway to tuneable thin emitters that can be utilized for large-area imaging, microscopy, and spectroscopy. In literature, THz-emitting metasurfaces generally exhibit high absorption, being based either on metals or on semiconductors excited in highly resonant regimes. Here, the use of a fully dielectric semiconductor exploiting morphology-mediated resonances and inherent quadratic nonlinear response is proposed. This system exhibits a remarkable 40-fold efficiency enhancement compared to the unpatterned at the peak of the optimized wavelength range, demonstrating its potential as a scalable emitter design

    Science communication and concept of risk in bio-tech-sciences: Is it a part of neo-liberalism, or foucaultian bio-politics?

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    In this work a Raman flow cytometer is presented. It consists of a microfluidic device that takes advantages of the basic principles of Raman spectroscopy and flow cytometry. The microfluidic device integrates calibrated microfluidic channels- where the cells can flow one-by-one -, allowing single cell Raman analysis. The microfluidic channel integrates plasmonic nanodimers in a fluidic trapping region. In this way it is possible to perform Enhanced Raman Spectroscopy on single cell. These allow a label-free analysis, providing information about the biochemical content of membrane and cytoplasm of the each cell. Experiments are performed on red blood cells (RBCs), peripheral blood lymphocytes (PBLs) and myelogenous leukemia tumor cells (K562)

    MITS: the Multi-Imaging Transient Spectrograph for SOXS

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    The Son Of X-Shooter (SOXS) is a medium resolution spectrograph R~4500 proposed for the ESO 3.6 m NTT. We present the optical design of the UV-VIS arm of SOXS which employs high efficiency ion-etched gratings used in first order (m=1) as the main dispersers. The spectral band is split into four channels which are directed to individual gratings, and imaged simultaneously by a single three-element catadioptric camera. The expected throughput of our design is >60% including contingency. The SOXS collaboration expects first light in early 2021. This paper is one of several papers presented in these proceedings describing the full SOXS instrument
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