59 research outputs found

    Vapor-Phase Oxidation of Benzyl Alcohol Using Manganese Oxide Octahedral Molecular Sieves (OMS-2)

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    Vapor-phase selective oxidation of benzyl alcohol has been accomplished using cryptomelane-type manganese oxide octahedral molecular sieve (OMS-2) catalysts. A conversion of 92% and a selectivity to benzaldehyde of 99% were achieved using OMS-2. The role played by the oxidant in this system was probed by studying the reaction in the absence of oxidant. The natures of framework transformations occurring during the oxidation reaction were fully studied using temperature-programmed techniques, as well as in situ X-ray diffraction under different atmospheres

    Consensus Paper: Radiological Biomarkers of Cerebellar Diseases

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    Hereditary and sporadic cerebellar ataxias represent a vast and still growing group of diseases whose diagnosis and differentiation cannot only rely on clinical evaluation. Brain imaging including magnetic resonance (MR) and nuclear medicine techniques allows for characterization of structural and functional abnormalities underlying symptomatic ataxias. These methods thus constitute a potential source of radiological biomarkers, which could be used to identify these diseases and differentiate subgroups of them, and to assess their severity and their evolution. Such biomarkers mainly comprise qualitative and quantitative data obtained from MR including proton spectroscopy, diffusion imaging, tractography, voxel-based morphometry, functional imaging during task execution or in a resting state, and from SPETC and PET with several radiotracers. In the current article, we aim to illustrate briefly some applications of these neuroimaging tools to evaluation of cerebellar disorders such as inherited cerebellar ataxia, fetal developmental malformations, and immune-mediated cerebellar diseases and of neurodegenerative or early-developing diseases, such as dementia and autism in which cerebellar involvement is an emerging feature. Although these radiological biomarkers appear promising and helpful to better understand ataxia-related anatomical and physiological impairments, to date, very few of them have turned out to be specific for a given ataxia with atrophy of the cerebellar system being the main and the most usual alteration being observed. Consequently, much remains to be done to establish sensitivity, specificity, and reproducibility of available MR and nuclear medicine features as diagnostic, progression and surrogate biomarkers in clinical routine

    Effect of hydrotechnical structures on the water economy renaturization in Zagorow Polder

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    The objective of the presented paper was the analysis of the effect of embankment culverts P7 and P8, built within the compensation work, on the water management of the Zagorow Polder. Before the year 2009, the polder formed the closed part of Kaminsko-Pyzderska Valley, completely cut off them by the river embankment from the periodically rising of Warta river. For the necessary calculation purposes, a mahematical model has been applied which permits to calculate the transformation of the flood waves. Additionally, the model has been enriched, among others, by a module permitting to calculate the water flow through the water installations like culverts, overflows, pumping stations, or reservoirs. This model has been constructed on the basis of digitalized points of river network and the added to it (through milage expressed in kilometgres) river cross-sections. The points of river network were introduced directly to a digitalized screen of topogtraphic maps of the given area and additionally by the utilization of the data base of XY points from digital vecor layers. All calculations were carried out on a one-dimensional model Mike 11 of a Danish Institute of Hydrology which includes the Saint Venant system of equation continuity and momentum conservation. The performed analyses have shown, that during freshet occurrence in the Warta river bed, it is necessary to open the P7 and P8 culverts in 50%. Then, there will follow a water supply to the Zagorow Polder by the Warta river until the level in the embankment culvert and in the polder will equalize. The emptying of the polder should be supported by the work of the pumping station. A gravitational outflow, after the opening of culverts PW1, PW2, P7 and P8 is not possible before the water level in WArta river descends. The time of polder emptying from the excess of water, according to to the experiments on the model, can be shdortened to about 11 days. In order to fulfill this condition, it is necessary to limit the overfilling of the Zagorow polder by the culverts P7 and P8 5 to the level of 76.2 m a.s.l (above sea level). This limitation results from the actual operating conditions of Zagorow intermediate pumping station. According to the valid operation instruction, the intermediate pumping station works within the following switch on levels of the pumping units: 76.90 m a.s.l. and the level of the switching off of the pumping aggregates: 75.50 m a.s.l

    Guidelines on CMV congenital infection

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    Congenital cytomegalovirus (CMV) infection occurs in 0.6–0.7% of all newborns and is the most prevalent infection-related cause of congenital neurological handicap. Vertical transmission occurs in around 30% of cases, but the fetus is not always affected. Symptomatic newborns at birth have a much higher risk of suffering severe neurological sequelae. Detection of specific IgG and IgM and IgG avidity seem to be the most reliable tests to identify a primary infection but interpretation in a clinical context may be difficult. If a seroconversion is documented or a fetal infection is suspected by ultrasound markers, an amniocentesis should be performed to confirm a vertical transmission. In the absence of a confirmed fetal infection with fetal structural anomalies, a pregnancy termination should be discouraged. Fetal prognosis is mainly correlated to the presence of brain damage. Despite promising results with the use of antiviral drugs and CMV hyperimmune globulin (HIG), results have to be interpreted with caution. Pregnant women should not be systematically tested for CMV during pregnancy. Managing CMV screening should be restricted to pregnancies where a primary infection is suspected or among women at high risk. The magnitude of congenital CMV disease and the value of interventions to prevent its transmission or to decrease the sequelae need to be established before implementing public health interventions. In this paper, aspects of CMV infection in the pregnant woman and her infant are reviewed.Peer Reviewe
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