630 research outputs found

    Blood lead levels in pregnant women and the neonate

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    Population studies carried out during the 1980s had shown that the Maltese population was characterized by high blood lead (PbB) levels. These high levels appeared to be a feature at all age groups including neonates. A number of environmental control measures had been initiated to attempt to decrease these PbB levels. The present study reviews PbB levels in pregnant women and newborns. It is shown that mean cord PbB levels decreased significantly in the last decade from a mean of 165.1 + 87.9 ug/I in 1985 to 89.79 + 31.23 ug/I in 1996. This decrease did not correlate with the increasing use of multimineral supplements which include the zinc cation said to be useful to counter the effects of chronic lead intoxication. Placental transfer of lead is also shown to follow closely maternal levels with a correlation coefficient of 0.81. In spite of the apparent decrease in PbB levels, about half of newborns still I have levels which require preventive community measures.peer-reviewe

    Development of a qualification standard for adhesives used in hybrid microcircuits

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    Improved qualification standards and test procedures for adhesives used in microelectronic packaging are developed. The test methods in specification for the Selection and Use of Organic Adhesives in Hybrid Microcircuits are reevaluated versus industry and government requirements. Four electrically insulative and four electrically conductive adhesives used in the assembly of hybrid microcircuits are selected to evaluate the proposed revised test methods. An estimate of the cost to perform qualification testing of an adhesive to the requirements of the revised specification is also prepared

    IMPLEMENTAZIONE DI TECNICHE DI TERMOGRAFIA ATTIVA IRNDT SU COMPOSITI GRP MEDIANTE LA DEPOSIZIONE DI IMPULSI TERMICI DI LUNGA DURATA

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    Nel presente lavoro viene analizzata l\u2019implementazione di tecniche attive di termografia ad infrarossi per analisi NDT su pannelli in composito. In particolare si propone l\u2019uso di lampade alogene come sorgente di calore esterna, le quali richiedono tempi di accensione dell\u2019ordine di diversi secondi al fine di depositare efficaci quantit\ue0 di calore. Si discutono quindi le problematiche connesse all\u2019implementazione di tecniche di Transient Thermography e di Lock-In Thermography in presenza di tempi lunghi di deposizione di calore. Viene implementata una tecnica di modulazione della deposizione di calore mediante treni di onde quadre di lunga durata (PMLT - Pulse Modulated Lock-In Thermography). Viene in particolare analizzata l\u2019influenza del periodo dell\u2019onda quadra, e del rapporto di acceso-spento del treno di onde quadre, attraverso l\u2019analisi dell\u2019andamento del contrasto di fase al variare della frequenza di correlazione (lock-in frequency)

    Design guidelines for use of adhesives and organic coatings in hybrid microcircuits

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    A study was conducted to investigate the reliability of organic adhesives in hybrid microcircuits. The objectives were twofold: (1) to identify and investigate problem areas that could result from the use of organic adhesives and (2) to develop evaluation tests to quantify the extent to which these problems occur for commercially available adhesives. Efforts were focused on electrically conductive adhesives. Also, a study was made to evaluate selected organic coatings for contamination protection for hybrid microcircuits

    Ab initio based equation of state of dense water for planetary and exoplanetary modeling

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    This is the author accepted manuscript. The final version is available from EDP Sciences via the DOI in this record.As a first step toward a multi-phase equation of state for dense water, we develop a temperature-dependent equation of state for dense water covering the liquid and plasma regimes and extending to the super-ionic and gas regimes. This equation of state covers the complete range of conditions encountered in planetary modeling. We use first principles quantum molecular dynamics simulations and its Thomas-Fermi extension to reach the highest pressures encountered in giant planets several times the size of Jupiter. Using these results, as well as the data available at lower pressures, we obtain a parametrization of the Helmholtz free energy adjusted over this extended temperature and pressure domain. The parametrization ignores the entropy and density jumps at phase boundaries but we show that it is sufficiently accurate to model interior properties of most planets and exoplanets. We produce an equation of state given in analytical form that is readily usable in planetary modeling codes and dynamical simulations {\bf (a fortran implementation can be found at http://www.ioffe.ru/astro/H2O/)}. The EOS produced is valid for the entire density range relevant to planetary modeling, {\bf for densities where quantum effects for the ions can be neglected, and for temperatures below 50,000K. We use this equation of state to calculate the mass-radius relationship of exoplanets up to 5,000M_Earth, explore temperature effects in ocean and wet Earth-like planets, and quantify the influence of the water EOS for the core on the gravitational moments of Jupiter.s. Part of this work was supported by the SNR grant PLANETLAB 12-BS04-0015 and the Programme National de Planetologie (PNP) of CNRS-INSU co-funded by CNES. Funding and support from Paris Sciences et Lettres (PSL) university through the project origins and conditions for the emergence of life is also acknowledged. This work was performed using HPC resources from GENCI- TGCC (Grant 2017- A0030406113

    Controversies in the treatment of mild asthma. What novelties and practical implications?

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    Mild asthma is prevalent in childhood and causes as many as 30%–40% asthma exacerbations requiring emergency visits. The management of "intermittent" and "mild persistent" asthma phenotypes is still a matter of debate, even if the role of inhaled corticosteroids, both continuous and intermittent, is a cornerstone in this field. Recent updates of the guidelines on the strategies to manage these patients are coming, since the role of inflammation in these asthma phenotypes is crucial, as well as the potential side effect and risks of short-acting beta 2 agonists overuse, prescribed as the only "as-needed" treatments. In this paper, we overview the new (r)evolution regarding intermittent and mild persistent asthma management

    Rhinosinusitis and asthma: a very long engagement

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    Upper and lower airways may be considered as a unique entity, interested by coexisting inflammatory processes that share common etiopathogenic mechanisms. Previous studies have strongly demonstrated a relationship between rhinosinusitis and asthma. This has led to the introduction of the concept of United Airways , which has also been included in the WHO document Allergic Rhinitis and its Impact on Asthma (ARIA); this concept has important consequences also on the treatment of these disorders. To better summarize the evident connection between upper and lower airway disease we decided to describe it as a multilayered construction, each level pointing out more deeply the relationship between these entities

    Immunomodulation in pediatric asthma

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    Childhood asthma is actually defined as a heterogeneous disease, including different clinical variants and partially sharing similar immune mechanisms. Asthma management is mainly focused on maintaining the control of the disease and reducing the risk of adverse outcomes. Most children achieve good control with standard therapies, such as low doses of inhaled corticosteroids (ICS) and/or one or more controller. These medications are targeted to suppress bronchial inflammation and to restore airway responsiveness. However, they are not disease-modifying and do not specifically target inflammatory pathways of asthma; in addition, they are not significantly effective in patients with severe uncontrolled asthma. The aim of this review is to update knowledge on current and novel therapeutic options targeted to immunomodulate inflammatory pathways underlying pediatric asthma, with particular reference on biologic therapies
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