25 research outputs found

    Silicon everywhere, Journal of Telecommunications and Information Technology, 2004, nr 1

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    The paper discusses the ubiquity of silicon and its compounds in the geo-chemical structure of the Earth. The dominant role of mineral oxidized compounds of silicon as the building material of the primordial magma, metamorphic and sedimentary rocks is also shown. The reader's attention is also attracted to the numerous varieties of silicon compounds valued for their intrinsic beauty. Finally, methods of silicon production for electronics purposes are briefly addressed

    Echocardiographic assessment of tricuspid regurgitation and pericardial effusion after cardiac device implantation

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    Background: The frequency of cardiac implantable electronic device (CIED) implantations is constantly increasing. Pericardial effusion (PE) and tricuspid regurgitation (TR) may occur after CIED implantation. The aim of the present study is to evaluate the prevalence and risk factors for new occurrences or progression of TR and PE early after CIED implantation. Methods: This is an on-going, single-center, observational study of patients after their first CIED implantation, with an echocardiographic evaluation within 60 days before and 7 days after the procedure. Data are presented for first 110 consecutive patients who underwent CIED implantation from August 2015 to July 2016. Results: Median age was 75 years, and 44% were women. In total, 87 (79%) pacemakers, 21 (19%) implantable cardioverter-defibrillators and 2 cardiac resynchronization therapy devices were implanted. After CIED implantation, there was TR progression in 17 (16%) patients: 5 patients developed moderate TR, none developed severe TR. An increase in TR was more often observed after implantations performed by operators in training than by certified operators (35% vs. 12%, p = 0.02). New PE after the procedure was observed in 8 (7%) patients and was trivial ( < 5 mm) in all cases. Patients with new PE after implantation had lower baseline hemoglobin levels and tended to be women. Conclusions: New PE and an increase in TR severity are rare complications early after CIED implantation. Operator experience might be related to TR progression. Increasing the number of patients in the current on-going study will allow a more reliable assessment of the prevalence and risk factors of these complications

    Rising temperatures advance the main flight period of Bombus bumblebees in agricultural landscapes of the Central European Plain

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    Funder: Poznan University of Life SciencesAbstractThis study examined shifts over a 35-year period in the phenology of the four most important bumblebee species (Bombus terrestris, B. lapidarius, B. pascuorum and B. hortorum) in Central Europe. The species showed similar temporal trends, significantly advancing components of their main flight period in association with rising temperatures such that, for example, mid-dates of the main flight period advanced by 10–23 days over the study period. Drivers of this change differed between the four species. Trends in, and drivers of, the timing of first queens, first workers and first males were less consistent. Aspects of the phenology of the least common species, B. hortorum, were up to a month earlier than the other species and climatic effects less clear cut. There were some suggestions of differences between species trends. These results stress the importance of considering changes and drivers of change for the Bombus family on a species-specific basis with the need to pay more attention to the life history traits of the study organisms.</jats:p
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