1,394 research outputs found

    Automated Setup to Accurately Calibrate Electrical DC Voltage Generators

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    At National Institute of Metrological Research (INRIM), an automated setup to calibrate DC Voltage generators, mainly top-level calibrators from 1 mV to 1 kV has been developed. The heart of the setup is an INRIM-built automated fixed ratios DC Voltage divider. The significant achievement of this setup is the possibility to interconnect the divider, a DMM characterized in linearity, a DC Voltage Standard and a DC Voltage generator under calibration and automatically to manage the calibration process. This calibration method allows to save a lot of time, to improve the reliability and to increase the accuracy of the calibration of generators. The relative uncertainties of the system span from 0.6x10-6 to 1.2x10-4 improving the previous capabilities of the INRIM laboratory for calibration of programmable multifunction instruments. In addition, this system allows to avoid the employment of several Standards (some of them still manually operating) carrying out the entire process without changing the setup configuration and without the presence of operators. The concept of this setup can be transferred to secondary high-level electrical calibration Laboratories that could be consider it useful for their calibration activities.Comment: 6 pages 8 figure

    Automatic DC voltage precision resistive divider with ratios between 10:1 and 107:1

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    At INRIM a DC Voltage precision resistive divider performing decade ratios from 10:1 to 107:1 was built. It can be automatically calibrated with a top-class calibrator and a precision multimeter calibrated in terms of deviation from linearity. It is made up of 90 kΩ, 9 kΩ, 900 Ω, 90 Ω, 9 Ω, 0.9 Ω, 90 mΩ and 10 mΩ bulk metal foil resistors connected in series, in four-terminal configuration. Peculiarities of the calibration method of the divider are: the evaluation of the DMM input impedance to correct its readings minimizing the load error and a solution to reduce the emfs effect of the relays. These operations are made during the calibration of the divider. The calibration and use uncertainties of the divider span respectively from 6.1 × 10 7 to 5.9 × 10 4 and from 6.7 × 10 7 to 6.5 × 10 4. The project is transferable to secondary laboratories in the framework of the INRIM knowledge transfer task

    High perfomance selectable value transportable high dc Voltage standard

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    At National Institute of Metrological Research (INRIM), a selectable-value Transportable High dcVoltage Standard (THVS) operating in the range from 10 V to 100 V in steps of 10 V, was developed. This Standard was built to cover the lack of high level dc Voltage Standards at voltages higher than 10 V to employ as laboratory (local) or travelling Standards for Inter-Laboratory Comparisons (ILCs). A ground-mobile electronic technique was used to enhance the accuracy of the THVS at the higher values. The THVS shows better noise, better short-mid-term stability than top level dc Voltage and multifunction calibrators (MFCs) and better suitability and insensibility to be transported than these instruments. The project is extensible to 1000 V

    Immunoexpression of aromatase and estrogen receptors beta in stem spermatogonia of bullfrogs indicates a role of estrogen in the seasonal spermatogonial mitotic activity

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    Bullfrog stem spermatogonia, also named primordial germ cells (PGCs), show strong testosterone immunolabeling in winter, but no or weak testosterone immunoexpression in summer. Thus, the role of testosterone in these cells needs to be clarified. in this study, we proposed to evaluate whether PGCs express aromatase and estrogen receptors, and verify a possible role of estrogen in PGCs seasonal proliferation. Testes of male adult bullfrogs, collected in winter (WG) and summer (SG), were fixed and embedded in historesin, for quantitative analysis, or paraffin for immunohistochemistry (IHC). the number of haematoxylin/eosin stained PGCs/lobular area was obtained. Proliferating cell nuclear antigen (PCNA), aromatase, estrogen receptor beta (ER beta) and PCNA/ER beta double immunolabeling were detected by IHC. the number of PCNA-positive PGCs and the histological score (HSCORE) of aromatase and ER beta immunolabeled PGCs were obtained. Although the number of PGCs increased significantly in WG, a high number of PCNA-positive PGCs was observed in summer. Moreover, aromatase and ER beta HSCORE was higher in SG than WG. the results indicate that PGCs express a seasonal proliferative activity; the low mitotic activity in winter is related to the maximal limit of germ cells which can be supported in the large lobules. in SG, the increased ER beta and aromatase HSCORE suggests that testosterone is converted into estrogen from winter to summer. Moreover, the parallelism between the high PGCs mitotic activity and ER beta immunoexpression suggest a participation of estrogen in the control of the PGCs seasonal proliferative activity which guarantee the formation of new germ cysts from summer to next autumn. (c) 2012 Elsevier Inc. All rights reserved.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação para o Desenvolvimento da UNESP (FUNDUNESP)Fed Univ São Paulo UNIFESP, Dept Morphol & Genet, São Paulo, BrazilUniv Estadual Paulista, UNESP, Sch Pharmaceut Sci, Dept Biol Sci, Araraquara, BrazilUniv Estadual Paulista, UNESP, Sch Dent, Dept Morphol,Lab Histol & Embryol, Araraquara, BrazilFed Univ São Paulo UNIFESP, Dept Morphol & Genet, São Paulo, BrazilFAPESP: 2009/17895-5FUNDUNESP: 00661/04-DFPWeb of Scienc

    Molecular approach for insect detection in feed and food: the case of Gryllodes sigillatus

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    The production of insects on an industrial scale has attracted the attention of the research and agricultural industry as novel protein sources. To detect the presence of Gryllodes sigillatus (GS) in feed and food, a real-time PCR method based on the mitochondrial cytochrome b (CYB) gene is proposed by this study. Forty DNA samples of animal and plant origin were used to confirm the specificity of the qPCR system. The detection method\u2019s performance was evaluated on different processed GS matrices including native GS (UnGS) and different commercial products: crunchy roasted samples (RoGS), insect meal mixtures (ACGS) and energetic snacks containing GS (GSS). Data on sequencing were aligned with the reference gene to confirm the PCR products. The regression curve (y = 123.394 x + 42.521; R2 = 0.994, d.f. 14) between Ct values and Log DNA concentrations of Gryllodes sigillatus resulted in an efficiency of 96.4%. The severity of the technological processing treatments and the matrix structure affected the intensity of the PCR signal with the same amount of insect DNA as observed by different y-intercepts of the three-regression lines for RoGS, ACGS, and GSS. The real-time PCR method resulted in robust and sensitive outcomes able to detect low amounts of GS DNA (5 g/100 g) in a complex matrix, making it suitable for detecting the presence or absence of labeled Gryllodes sigillatus material both in feed and food

    REM Sleep and Endothermy: Potential Sites and Mechanism of a Reciprocal Interference

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    Numerous data show a reciprocal interaction between REM sleep and thermoregulation. During REM sleep, the function of thermoregulation appears to be impaired; from the other hand, the tonic activation of thermogenesis, such as during cold exposure, suppresses REM sleep occurrence. Recently, both the central neural network controlling REM sleep and the central neural network controlling thermoregulation have been progressively unraveled. Thermoregulation was shown to be controlled by a central "core" circuit, responsible for the maintenance of body temperature, modulated by a set of accessory areas. REM sleep was suggested to be controlled by a group of hypothalamic neurons overlooking at the REM sleep generating circuits within the brainstem. The two networks overlap in a few areas, and in this review, we will suggest that in such overlap may reside the explanation of the reciprocal interaction between REM sleep and thermoregulation. Considering the peculiar modulation of thermoregulation by REM sleep the result of their coincidental evolution, REM sleep may therefore be seen as a period of transient heterothermy

    Mindfulness-based stress reduction in patients with interstitial lung diseases: a pilot, single-centre observational study on safety and efficacy

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    open11siBackground Chronic, progressive respiratory symptoms are associated with great psychological and emotional impact in patients suffering from interstitial lung disease (ILD). This single-centre pilot study evaluated for the first time the safety, feasibility and efficacy of a Mindfulness Based Stress Reduction Program (MBSR) in a group of patients with ILD. Methods Prospective observational study set in a university hospital ILD outpatient clinic. Nineteen patients with different ILDs were recruited 2 months prior to the start of the 8-week MBSR program and followed up for 12 months. Primary outcomes were program safety and feasibility, while secondary outcomes were changes in moods and stress (assessed by Profile Of Mood State (POMS) and Perceived Stress Scale (PSS) questionnaires), symptoms (Shortness Of Breath (SOB) and Cough And Sputum Assessment (CASA-Q) questionnaires), lung function and exercise tolerance at 12 months. Results Two patients (10.5%) dropped out in the observational period before the start of the MBSR intervention because of non-respiratory causes. All 17 patients who entered the 8-week MBSR program managed to complete it with an adherence average of eight sessions of nine. No adverse events related to the mindfulness training were reported. Statistically significant improvements in the POMS total score and in several individual items of POMS and PSS were observed throughout the study. However, respiratory questionnaire scores, lung function and exercise tolerance did not show a significant difference over time. Conclusions An MBSR program appears to be safe and feasible in patients with ILD, and might affect perceived moods and stress producing a positive and lasting improvement in several stress-related negative domains. These findings pave the way to larger (possibly multicentre), randomised, controlled confirmatory trials.openSgalla, Giacomo; Cerri, Stefania; Ferrari, Roberto; Ricchieri, Maria Pia; Poletti, Stefano; Ori, Margherita; Garuti, Martina; Montanari, Gloria; Luppi, Fabrizio; Petropulacos, Kyriakoula; Richeldi, LucaSgalla, Giacomo; Cerri, Stefania; Ferrari, Roberto; Ricchieri, Maria Pia; Poletti, Stefano; Ori, Margherita; Garuti, Martina; Montanari, Gloria; Luppi, Fabrizio; Petropulacos, Kyriakoula; Richeldi, Luc

    Janus-faced amiodarone-induced pneumopathy

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    The authors describe a patient showing bilateral, peripheral, predominantly basal ground-glass and reticular opacities consistent with a non-specific interstitial pneumonia (NSIP) radiological pattern. This was followed by the occurrence of two nodules that progressively decreased in size after oral steroids had been given and therefore they were interpreted as an unusual manifestation of amiodarone-related pulmonary toxicity (APT)

    Processes that influence dissolved organic matter in the soil: a review

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    In tropical regions, climate conditions favor fast decomposition of soil organic matter (SOM), releasing into the soil organic composts in solid, liquid, and gaseous forms with variable compositions. Dissolved organic matter (DOM), a complex mixture of thousands of organic compounds, is only a small fraction of the decomposition products; however, it is highly mobile and reactive to the soil. Therefore, DOM play a key role in soil aggregation (formation of organometallic complexes), energy source for microorganisms, as well as C storage, cycling, and provision of plant-available nutrients. DOM multifunctionality to sustain soil functions and important ecosystem services have raised global scientific interest in studies on DOM fractions. However, previous studies were conducted predominantly under temperate soil conditions in natural ecosystems. Therefore, there is paucity of information on tropical soil conditions under agricultural systems, where DOM turnover is intensified by management practices. This review synthesized information in the literature to identify and discuss the main sources, transformations, and future of DOM in soils. We also discussed the importance of this fraction in C cycling and other soil properties and processes, emphasizing agricultural systems in tropical soils. Gaps and opportunities were identified to guide future studies on DOM in tropical soils
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