1,443 research outputs found

    Espoused curriculum and philosophy and curriculum and philosophy-in-use in a K-12 public charter school system

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    Fan Loops Observed by IRIS, EIS and AIA

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    A comprehensive study of the physical parameters of active region fan loops is presented using the observations recorded with the Interface Region Imaging Spectrometer (IRIS), the EUV Imaging Spectrometer (EIS) on-board Hinode and the Atmospheric Imaging Assembly (AIA) and the Helioseismic and Magnetic Imager (HMI) on-board the Solar Dynamics Observatory (SDO). The fan loops emerging from non-flaring AR~11899 (near the disk-center) on 19th November, 2013 are clearly discernible in AIA 171~{\AA} images and those obtained in \ion{Fe}{8} and \ion{Si}{7} images using EIS. Our measurements of electron densities reveal that the footpoints of these loops are approximately at constant pressure with electron densities of logNe=\log\,N_{e}= 10.1 cm3^{-3} at log[T/K]=5.15\log\,[T/K]=5.15 (\ion{O}{4}), and logNe=\log\,N_{e}= 8.9 cm3^{-3} at log[T/K]=6.15\log\,[T/K]=6.15 (\ion{Si}{10}). The electron temperature diagnosed across the fan loops by means of EM-Loci suggest that at the footpoints, there are two temperature components at log[T/K]=4.95\log\,[T/K]=4.95 and 5.95, which are picked-up by IRIS lines and EIS lines respectively. At higher heights, the loops are nearly isothermal at log[T/K]=5.95\log\,[T/K]=5.95, that remained constant along the loop. The measurement of Doppler shift using IRIS lines suggests that the plasma at the footpoints of these loops is predominantly redshifted by 2-3~km~s1^{-1} in \ion{C}{2}, 10-15~km~s1^{-1} in \ion{Si}{4} and  ~15{--}20~km~s1^{-1} in \ion{O}{4}, reflecting the increase in the speed of downflows with increasing temperature from log[T/K]=4.40\log\,[T/K]=4.40 to 5.15. These observations can be explained by low frequency nanoflares or impulsive heating, and provide further important constraints on the modeling of the dynamics of fan loops.Comment: Accepted for publication in The Astrophysical Journal; 8 Figures, 11 page

    Analysis of Metal Cutting Acoustic Emissions by Time Series Models

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    We analyse some acoustic emission time series obtained from a lathe machining process. Considering the dynamic evolution of the process we apply two classes of well known stationary stochastic time series models. We apply a preliminary root mean square (RMS) transformation followed by an ARMA analysis; results thereof are mainly related to the description of the continuous part (plastic deformation) of the signal. An analysis of acoustic emission, as some previous works show, may also be performed with the scope of understanding the evolution of the ageing process that causes the degradation of the working tools. Once the importance of the discrete part of the acoustic emission signals (i.e. isolated amplitude bursts) in the ageing process is understood, we apply a stochastic analysis based on point processes waiting times between bursts and to identify a parameter with which to characterise the wear level of the working tool. A Weibull distribution seems to adequately describe the waiting times distribution

    Chronic kidney disease: Which role for xanthine oxidoreductase activity and products?

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    The present review explores the role of xanthine oxidoreductase (XOR) in the development and progression of chronic kidney disease (CKD). Human XOR is a multi-level regulated enzyme, which has many physiological functions, but that is also implicated in several pathological processes. The main XOR activities are the purine catabolism, which generates uric acid, and the regulation of cell redox state and cell signaling, through the production of reactive oxygen species. XOR dysregulation may lead to hyperuricemia and oxidative stress, which could have a pathogenic role in the initial phases of CKD, by promoting cell injury, hypertension, chronic inflammation and metabolic derangements. Hypertension is common in CKD patients and many mechanisms inducing it (upregulation of renin-angiotensin-aldosterone system, endothelial dysfunction and atherosclerosis) may be influenced by XOR products. High XOR activity and hyperuricemia are also risk factors for obesity, insulin resistance, type 2 diabetes and metabolic syndrome that are frequent CKD causes. Moreover, CKD is common in patients with gout, which is characterized by hyperuricemia, and in patients with cardiovascular diseases, which are associated with hypertension, endothelial dysfunction and atherosclerosis. Although hyperuricemia is undoubtedly related to CKD, controversial findings have been hitherto reported in patients treated with urate-lowering therapies

    Gateway Discovery and Selection in Mobile Hotspots

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    Gaining IP connectivity in mobile hotspots (e.g. public transport vehicles) through on-board local area networks and mobile gateways has recently attracted strong commercial and research interests. In this paper we propose a multi-dimensional protocol to support the process of gatewaydiscovery in mobile hotspots, and to help in selecting the best path able to satisfy the user's requirements and to guarantee a target end-to-end service quality. Our proposal is based on highly popular and almost standard protocols, such as SDPng for session description and AODV for route discovery

    Ricin: An ancient story for a timeless plant toxin

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    The castor plant (Ricinus communis L.) has been known since time immemorial in traditional medicine in the pharmacopeia of Mediterranean and eastern ancient cultures. Moreover, it is still used in folk medicine worldwide. Castor bean has been mainly recommended as anti-inflammatory, anthelmintic, anti-bacterial, laxative, abortifacient, for wounds, ulcers, and many other indications. Many cases of human intoxication occurred accidentally or voluntarily with the ingestion of castor seeds or derivatives. Ricinus toxicity depends on several molecules, among them the most important is ricin, a protein belonging to the family of ribosome-inactivating proteins. Ricin is the most studied of this category of proteins and it is also known to the general public, having been used for several biocrimes. This manuscript intends to give the reader an overview of ricin, focusing on the historical path to the current knowledge on this protein. The main steps of ricin research are here reported, with particular regard to its enzymatic activity, structure, and cytotoxicity. Moreover, we discuss ricin toxicity for animals and humans, as well as the relation between bioterrorism and ricin and its impact on environmental toxicity. Ricin has also been used to develop immunotoxins for the elimination of unwanted cells, mainly cancer cells; some of these immunoconjugates gave promising results in clinical trials but also showed critical limitation

    The indigenous settlement of Monte Iato (western Sicily): an ethnoarchaeometric approach for outlining local Archaic ceramic productions

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    An ethnoarchaeometric approach has been followed to identify the textural and compositional characteristics of the ceramic pastes produced in ancient Iaitas/Ietas, an indigenous site located in western Sicily on Monte Iato, a few tens of kilometres from Palermo. This approach was primarily motivated by the lack of discovered Archaic kilns or production sites/workshops and the inability to identify reference groups. Raw clays were sampled in the territory of San Cipirello and San Giuseppe Iato (today\u2019s municipalities both sited on the northern slopes of Monte Iato), together with representative historic tiles and bricks locally produced until fairly recently. Grain-size analysis and experimental firings were performed on the clay samples. A significant number of archaeological ceramic samples (incised and painted indigenous pottery dating back to the seventh\u2013fifth centuries BCE) from stratigraphic excavations on Monte Iato, and hypothesized as local productions on a stylistic-morphological basis, was carefully selected for archaeometric analysis. This set of samples (90 in total, comprising raw clays, historic tiles/bricks and archaeological ceramics) underwent a combined chemical and mineralogical-petrographic analysis to identify any possible compositional matching. This approach enabled the identification of minero-petrographic and chemical markers pertinent to the indigenous Archaic pottery produced at Monte Iato, although no evidence of coeval ceramic kilns has been found so far. Local raw clay sources have been documented and some significant points of the cha\ueene op\ue9ratoire adopted in antiquity have been noted (clay mixing and tempering practices). Attesting Monte Iato as a centre of ceramic production and defining both the microscopic fabric and the average composition of local pastes open up new perspectives in the complex issue concerning the production and regional circulation of incised and painted indigenous ceramics in Archaic Sicily

    Effects of mixed of a ketogenic diet in overweight and obese women with polycystic ovary syndrome

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    Polycystic ovary syndrome (PCOS) is a commonly occurring endocrine disorder characterized by hirsutism, anovulation, and polycystic ovaries. Often comorbid with insulin resistance, dyslipidemia, and obesity, it also carries significant risk for the development of cardiovascular and metabolic sequelae, including diabetes and metabolic syndrome. The relationship between central obesity and the development of insulin resistance is widely verified. Adipose tissue excess and the coexistent dysregulation of adipocyte functions directly contribute to the pathogenesis of the metabolic complications observed in women with PCOS. In the light of these evidence, the most therapeutic option prescribed to obese women with PCOS, regardless of the phenotype e from the severity of clinical expression, is lifestyle correction by diet and physical activity. The aim of this study is to evaluate the beneficial effects of ketogenic diet in 17 obese women with PCOS. Our results showed that the ketogenic diet inducing therapeutic ketosis, improves the anthropometric and many biochemical parameters such as LH, FSH, SHBG, insulin sensitivity and HOMA index. In addition, it induces a reduction in androgenic production, whereas the contextual reduction of fat mass reduced the acyclic production of estrogens deriving from the aromatization in the adipose tissue of the androgenic excess, with an improvement of the LH/FSH ratio. This is the first study on the effects of the ketogenic diet on PCOS, however, further studies are needed to elucidate the mechanism underlying ketogenic diet effects
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