177,288 research outputs found
Erratum: Acute exacerbation of interstitial lung diseases secondary to systemic rheumatic diseases: A prospective study and review of the literature (Journal of Thoracic Disease (2019) 11 (1621-1628) DOI: 10.21037/jtd.2019.03.28)
No full textIn the article that appeared on Page 1621-1628, Vol 11, No 4 (April 2019) Issue of the Journal of Thoracic Disease (1), the given and family names of author “Fabrizio Pancaldi” was incorrectly published in the original. The author's name should be corrected as Fabrizio Pancaldi, instead of Pancaldi Fabrizio. The authors regret the error
Deluc, Davy, and the impact of the battery on natural philosophy
No full textThis paper focuses on Deluc’s last contributions to the study of electricity. Printed between 1804 and 1815, they belong to an age dominated by what John L. Heilbron has called “The Standard Model of 1800.” The paper shows that Deluc was involved in the “broadening of the social base of experimental activity” connecting philosophers, instrument makers, and industrialists. A process which, according to Larry Stewart, characterized the “knowledge economy” around 1800. The increasing epistemological role credited to electrical apparatus went hand in hand with an increasing awareness of the role of artifacts and machines in culture at large. The paper shows that, in that same period, the science of electricity came to favor mid-range concepts and intellectual frugality over the search for broad systems of knowledge
Wartime chemistry in Italy: Industry, the military, and the professors
No full textThe First World War is often called the ‘chemists’ war’. But few realise precisely how, or the extent to which modern chemistry became a significant factor in the struggle, and would be in turn deeply shaped by it. Gathering momentum at first, by 1916, success in applying scientific knowledge to ‘frontline and factory’ became a measure of a nation’s capacity to win an industrial war. In the end, the titanic contest was won in large part through the command of raw materials and industrial output. This book represents a first considered attempt to study the factors that conditioned industrial chemistry for war in 1914-18. Taking a comparative perspective, it reflects on the experience of France, Germany, Austria, Russia, Britain, Italy and Russia, and points to significant similarities and differences. It looks at changing patterns in the organisation of industry, and at the emerging symbiosis between science, industry and the military, which contributed to the first ‘academic-military-industrial’ complex of the 20th century. At the same time, it reflects on the world’s first, and ultimately unsuccessful attempt to monitor ‘dual-use’ chemical technologies, and so restrict the proliferation of an important category of weapons of mass destruction
Time-varying metrics of cyclostationarity for bearing diagnostic
No full textBall bearings represent the most adopted solution to support rotating elements. Separated by the cage, the rolling elements are induced by the kinematics of the system to roll and accidentally slip on the rings. In working conditions the continuous contact of the elements leads to a wearing of the bearing surfaces. As a consequence, the early detection of faults represents an issue for modern diagnostic systems. The mathematical model of faulted rolling bearings has been extensively investigated in the last decades and it is widely accepted that a faulted bearing is subject to an unwanted slippery leading to a cyclostationary vibration signal. This paper presents a novel approach to the diagnosis of rolling bearings based on the statistical definition of cyclostationarity. In particular, various metrics have been devised to track the “cyclostationary signature” of the vibration signal and the performance of the proposed algorithms has been assessed through both experimental measurements and synthetic data. Numerical results have shown that the new approach to fault detection is comparable to conventional techniques based on spectral kurtosis, demodulation and spectral correlation, and it can outperform them in some cases; furthermore the simplicity of the proposed algorithms leads to an intrinsic robustness against the mechanical noise typical of practical scenarios
Considerazioni su un'esperienza di inserimento di bambini handicappati in un soggiorno estivo
No full textNO ABSTRAC
On the performance comparison of diagnostic techniques in machine monitoring
No full textPredictive maintenance can save a lot of efforts in modern industry and condition monitoring is attracting a lot of attention accordingly. New algorithms for fault detection appear frequently in the technical literature, however an objective, quantitative and widely accepted approach to performance comparison is still lacking. In this paper, we propose a new method leading to a fair and reproducible performance assessment. The proposed solution is based on vibrational analysis and consists of searching and detecting the theoretical cyclic frequencies that appear as a specific "signature" of a fault. Each algorithm for condition monitoring relies on a metric, then the main idea is to quantitatively characterize the peaks of the metric emerging from the machine noise. We think that the wide adoption of the proposed approach could significantly foster the research in the fields of condition monitoring and predictive maintenance
Multiple transcription start sites of the carrot dihydrofolate reductase-thymidylate synthase and sub-cellular localisation of the bifunctional protein
No full textThe analysis of clones obtained by rapid amplification of the 5' end and by primer extension of the mRNA for carrot bifunctional dihydrofolate reductase-thymidylate synthase showed transcripts of differing lengths that belonged to two sub-populations. The longer transcripts were found to contain a translation start site 147 nt upstream of, and in frame with, the one which is present in the shorter transcripts. The ORF that begins at this ATG codes for a protein of 64 714 Da, which is much larger than mature DHFR-TS subunit. The N-terminus region of this polypeptide shows features typical of plant transit peptides. Immunogold labelling studies and immunorecognition of the plastid-containing sub-cellular fraction suggested a plastidial localisation of the bifunctional protein. Although plant cells were shown to contain folate pools in plastids, in mitochondria and in the cytosol, few enzymes of the folate pathway have been associated with any sub-cellular compartment. Thus, this is the first indication for the presence of an enzyme of the folate biosynthetic pathway in plastids. The longer transcripts revealed the presence of a TC microsatellite at the 5'-untranslated end
CO<sub>2</sub> exchange, photosynthetic pigment composition, and cell ultrastructure of <i>Sphagnum</i> mosses during dehydration and subsequent rehydration
No full text Sphagnum mosses of three different species (S. capillifolium, S. magellanicum, and S. fallax) were allowed to dry in a controlled environment. The three species lost water at different rates, but after 11 days of exposure to drying atmosphere all were dry and unable to photosynthesize. The chlorophyllose cells of all three species showed signs of alteration, mainly membrane shrinkage. Upon rehydration, concentrations of photosynthetic pigments (chlorophyll a to a greater extent than chlorophyll b) declined in tissues of S. magellanicum and especially in S. fallax. Sphagnum capillifolium and S. magellanicum resumed photosynthesis, although slowly, whereas S. fallax did not achieve a net carbon gain (most of its chlorophyllose cells were irreversibly damaged) after 7 days of rewetting. In the field, prolonged drought may alter the interspecific equilibria among coexisting Sphagnum species possessing different degrees of desiccation-tolerance and especially different water-holding abilities. Keywords: Sphagnum, photosynthesis, ultrastructure, photosynthetic pigments, dehydration, rehydration. </jats:p
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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