180 research outputs found

    Analysis of ring laser gyroscopes including laser dynamics

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    Inertial sensors stimulate very large interest, not only for their application but also for fundamental physics tests. Ring laser gyros, which measure angular rotation rate, are certainly among the most sensitive inertial sensors, with excellent dynamic range and bandwidth. Large area ring laser gyros are routinely able to measure fractions of prad/s, with high duty cycle and bandwidth, providing fast, direct and local measurement of relevant geodetic and geophysical signals. Improvements of a factor 1010010-100 would open the windows for general relativity tests, as the GINGER project, an Earth based experiment aiming at the Lense-Thirring test at 1%1\% level. However, it is well known that the dynamics of the laser induces non-linearities, and those effects are more evident in small scale instruments. Sensitivity and accuracy improvements are always worthwhile, and in general there is demand for high sensitivity environmental study and development of inertial platforms, where small scale transportable instruments should be used. We discuss a novel technique to analyse the data, aiming at studying and removing those non-linearity. The analysis is applied to the two ring laser prototypes GP2 and GINGERINO, and angular rotation rate evaluated with the new and standard methods are compared. The improvement is evident, it shows that the back-scatter problem of the ring laser gyros is negligible with a proper analysis of the data, improving the performances of large scale ring laser gyros, but also indicating that small scale instruments with sensitivity of nrad/s are feasible.Comment: 9 pages and 7 figure

    Effect of the rearing substrate on total protein and amino acid composition in black soldier fly

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    Insects are becoming increasingly relevant as protein sources in food and feed. The Black Soldier Fly (BSF) is one of the most utilized, thanks to its ability to live on many leftovers. Vegetable processing industries produce huge amounts of by-products, and it is important to efficiently rear BSF on different substrates to assure an economical advantage in bioconversion and to overcome the seasonality of some leftovers. This work evaluated how different substrates affect the protein and amino acid content of BSF. BSF prepupae reared on different substrates showed total protein content varying between 35% and 49% on dry matter. Significant lower protein contents were detected in BSF grown on fruit by-products, while higher contents were observed when autumnal leftovers were employed. BSF protein content was mainly correlated to fibre and protein content in the diet. Among amino acids, lysine, valine and leucine were most affected by the diet. Essential amino acids satisfied the Food and Agricultural Organization (FAO) requirements for human nutrition, except for lysine in few cases. BSF could be a flexible tool to bio-convert a wide range of vegetable by-products of different seasonality in a high-quality protein-rich biomass, even if significant differences in the protein fraction were observed according to the rearing substrate

    Long-lasting beneficial effects of central serotonin receptor 7 stimulation in female mice modeling Rett syndrome.

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    Rett syndrome (RTT) is a rare neurodevelopmental disorder, characterized by severe behavioral and physiological symptoms. Mutations in the methyl CpG binding protein 2 gene (MECP2) cause more than 95% of classic cases, and currently there is no cure for this devastating disorder. Recently we have demonstrated that specific behavioral and brain molecular alterations can be rescued in MeCP2-308 male mice, a RTT mouse model, by pharmacological stimulation of the brain serotonin receptor 7 (5-HT7R). This member of the serotonin receptor family-crucially involved in the regulation of brain structural plasticity and cognitive processes-can be stimulated by systemic repeated treatment with LP-211, a brain-penetrant selective 5-HT7R agonist. The present study extends previous findings by demonstrating that the LP-211 treatment (0.25 mg/kg, once per day for 7 days) rescues RTT-related phenotypic alterations, motor coordination (Dowel test), spatial reference memory (Barnes maze test) and synaptic plasticity (hippocampal long-term-potentiation) in MeCP2-308 heterozygous female mice, the genetic and hormonal milieu that resembles that of RTT patients. LP-211 also restores the activation of the ribosomal protein (rp) S6, the downstream target of mTOR and S6 kinase, in the hippocampus of RTT female mice. Notably, the beneficial effects on neurobehavioral and molecular parameters of a seven-day long treatment with LP-211 were evident up to 2 months after the last injection, thus suggesting long-lasting effects on RTT-related impairments. Taken together with our previous study, these results provide compelling preclinical evidence of the potential therapeutic value for RTT of a pharmacological approach targeting the brain 5-HT7R

    Photoionization of ultracold and Bose-Einstein condensed Rb atoms

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    Photoionization of a cold atomic sample offers intriguing possibilities to observe collective effects at extremely low temperatures. Irradiation of a rubidium condensate and of cold rubidium atoms within a magneto-optical trap with laser pulses ionizing through 1-photon and 2-photon absorption processes has been performed. Losses and modifications in the density profile of the remaining trapped cold cloud or the remaining condensate sample have been examined as function of the ionizing laser parameters. Ionization cross-sections were measured for atoms in a MOT, while in magnetic traps losses larger than those expected for ionization process were measured.Comment: 9 pages, 7 figure

    Ion detection in the photoionization of a Rb Bose-Einstein condensate

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    Two-photon ionization of Rubidium atoms in a magneto-optical trap and a Bose-Einstein condensate (BEC) is experimentally investigated. Using 100 ns laser pulses, we detect single ions photoionized from the condenstate with a 35(10)% efficiency. The measurements are performed using a quartz cell with external electrodes, allowing large optical access for BECs and optical lattices.Comment: 14 pages, 7 figure

    Autofluorescence bronchoscopy to identify pre-cancerous bronchial lesions

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    Background. This study aimed to assess the diagnostic yield of autofluorescence bronchoscopy (AFB) in the detection of pre-cancerous bronchial lesions in a non-selected sample of patients. Methods. Both fiberoptic white-light bronchoscopy (WLB) and AFB using the Storz D-light system were performed on 166 consecutive patients. Biopsy specimens were taken in areas of the tracheobronchial tree judged as abnormal or suspicious at WLB and/or AFB. The bronchoscopic procedures were randomly performed by two operators. Results. A total of 93 patients had a positive biopsy specimen: 80 for cancer and 13 for dysplasia. AFB was abnormal or suspicious in 85 of the 93 patients with a sensitivity of 91.4%. Specificity was 50.7%. In 16 patients with normal WLB examination, AFB identified abnormal or suspicious areas which had a positive biopsy. Thus AFB significantly improved sensitivity of WLB (100% vs 82.8%, respectively, p<0.001) in the entire sample of patients studied. Data was further analysed separately for patients with dysplasia and those with cancer. Indeed, 13 of 16 patients recognized only by AFB had a histological diagnosis of dysplasia. The remaining three patients had a diagnosis of cancer (small intraepithelial neoplastic lesions). Since no other patient with dysplasia was found, AFB had a sensitivity of 100% in diagnosing dysplasia. On the other hand, excluding the 13 patients with dysplasia, WLB had a high sensitivity in diagnosing cancer (93.7%). Conclusions. The AFB Storz system showed a high sensitivity. The increase in diagnostic yield of AFB in comparison with WLB was related to the power of AFB to identify pre-cancerous bronchial lesions so showing its usefulness in the early diagnosis of lung cancer

    An underground Sagnac gyroscope with sub-prad/s rotation rate sensitivity: toward General Relativity tests on Earth

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    Measuring in a single location on Earth its angular rotation rate with respect to the celestial frame, with a sensitivity enabling access to the tiny Lense-Thirring effect is an extremely challenging task. GINGERINO is a large frame ring laser gyroscope, operating free running and unattended inside the underground laboratory of the Gran Sasso, Italy. The main geodetic signals, i.e., Annual and Chandler wobbles, daily polar motion and Length of the Day, are recovered from GINGERINO data using standard linear regression methods, demonstrating a sensitivity better than 1 prad/s, therefore close to the requirements for an Earth-based Lense-Thirring test.Comment: 7 pages, 5 figure

    Mapping synergies and trade-offs between energy and the Sustainable Development Goals

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    The 2030 Agenda for Sustainable Development—including 17 interconnected Sustainable Development Goals (SDGs) and 169 targets—is a global plan of action for people, planet and prosperity. SDG7 calls for action to ensure access to affordable, reliable, sustainable and modern energy for all. Here we characterize synergies and trade-offs between efforts to achieve SDG7 and delivery of the 2030 Agenda as a whole. We identify 113 targets requiring actions to change energy systems, and published evidence of relationships between 143 targets (143 synergies, 65 trade-offs) and efforts to achieve SDG7. Synergies and trade-offs exist in three key domains, where decisions about SDG7 affect humanity’s ability to: realize aspirations of greater welfare and well-being; build physical and social infrastructures for sustainable development; and achieve sustainable management of the natural environment. There is an urgent need to better organize, connect and extend this evidence, to help all actors work together to achieve sustainable development. On 5 September 2015, the 193 members states of the United Nations (UN) adopted a new 2030 Agenda for Sustainable Development. The 2030 Agenda succeeds the UN’s Millennium Development Goals (MDGs), and features 17 Sustainable Development Goals (SDGs) with 169 targets, which UN member states have committed to implement by 2030. Energy was not explicitly referred to in the MDGs, and came to be referred to as the ‘missing’ MDG. During the operational period of the MDGs and negotiation of the 2030 Agenda, it was increasingly recognized that energy underpins economic and social development, without which it would not be possible to eliminate poverty. This change in status made sustainable energy provision and access one of the central themes of the 2030 Agenda, whose preamble calls for “universal access to affordable, reliable and sustainable energy” and recognizes that “social and economic development depends of the sustainable management of our planet’s natural resources”. SDG7 is accompanied by five targets to be achieved by 2030: ensure universal access to affordable, reliable and modern energy services (7.1); increase the share of renewable energy in the global energy mix (7.2); double the global rate of improvement in energy efficiency (7.3); enhance international cooperation to facilitate access to clean energy research and technology (7.a), and promote investment in energy infrastructure and clean energy technology (7.b). By understanding the complex links between the SDGs and their constituent targets, researchers can better support policymakers to think systematically about interactions between the different SDGs, including how actions to achieve each goal affect each other within and between sectors. Studies to date have lacked a target-level approach or have focussed on only a few of the SDGs. Here we present a formative attempt by an interdisciplinary group of researchers to identify the full range of goals and targets in the 2030 Agenda that call for changes in energy systems, and characterize evidence of synergies or trade-offs between delivery of each of the 169 targets and efforts focussed on pursuit of SDG7 and each of its constituent targets. The purpose of this Perspective is not to provide definitive answers. Instead we aim to lay a foundation for systematic (and context-specific) exploration of the interlinkages between each of the SDG targets, in the context of decision-making about development and the transformation of energy systems
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