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Arianna Borrelli 《Centaurus; international magazine of the history of science and medicine》2020,62(3):406-424
In this paper, I suggest that research results from the history and philosophy of modern science provide a valuable methodological contribution for investigating early modern experimental philosophy and employ them to reassess the contribution of Giovan Battista Della Porta to its development. In modern science, the production of experimental knowledge is dependent on a complex array of communication strategies involving verbal terminology, diagrams, standardized instruments, and measurement units. Historians and philosophers have investigated the constitutive connection between such strategies and the phenomena scientists study in laboratories, showing how the two often co-evolved during the 19th and 20th centuries. Della Porta took an important first step towards the development of such methods by transforming the traditional recipe format into a strategy for mutually connecting, conceptualizing, and sharing observations made in experiments involving similar, but not identical, instruments and procedures. I use as a case study the changing manner in which he used recipes for presenting and connecting a number of pneumatic experiences from the first edition of Natural Magic (1558) until his meteorology treatise On Transmutations of Air (1610). In modern terms, those experiences can be interpreted as demonstrating the air's expansion and contraction with heat or pressure. However, today's notions of air pressure, density, and volume did not exist around 1600 and the verbal, visual, and quantitative means of expressing them had yet to be created. Della Porta did not create the modern notions, but he contributed to their emergence in a substantial way with his discussions of those pneumatic experiences. Della Porta's innovation may be described as the creation of a new epistemic genre, but it was not of a purely literary character, since the recipes also shaped the instruments and procedures they described, transforming them into new means of knowledge production in experimental philosophy. 相似文献
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PM Hartigan JC Giacomini ED Folland AF Parisi 《Canadian Metallurgical Quarterly》1998,82(12):1445-1450
Despite increasing use of percutaneous transluminal coronary angioplasty (PTCA) to treat stenotic coronary artery disease, there are relatively few prospective studies evaluating its long-term effectiveness. We prospectively randomized 212 stable patients with provocable myocardial ischemia and single-vessel subocclusive coronary disease to receive primary therapy with either PTCA or medical therapy. This report presents the clinical follow-up of these patients at a mean, after randomization, of 2.4 years for interview and 3.0 years for exercise testing. Of the 212 patients originally randomized, 175 received an extended follow-up interview, and 132 underwent exercise testing; 62% of patients in the PTCA group were angina free compared with 47% of patients in the medical group (p <0.05). Furthermore, exercise duration as measured by treadmill testing was prolonged by 1.33 minutes over baseline in the PTCA group, whereas it decreased by 0.28 minutes in the medical group (p <0.04). Although the angina-free time on the treadmill was not different (p=0.50), fewer patients in the medical group developed angina on the treadmill at 3 years than those in the PTCA group (p=0.04). By 36 months, excluding the initial randomized PTCA, use of PTCA and use of coronary artery bypass surgery were not different in the 2 treatment groups. These data indicate that some of the early benefits derived from PTCA in patients with single-vessel coronary artery disease are sustained, making it an attractive therapeutic option for these patients. 相似文献
35.
M. Benetti A. TarolliG. Giacomini C. PiemonteG.-F. Dalla Betta 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,658(1):61-65
Silicon photomultipliers (SiPMs) coupled to fast bright scintillators, like cerium doped silicate based crystals, allow the construction of compact gamma ray detectors. In this paper we discuss simulation results obtained from Monte Carlo ray tracing tools applied to SiPM and LYSO systems. We address the importance of three key factors in light propagation: the scintillator wrapping, the coupling medium, and the detector coating. We also propose a simple experiment to verify some of the findings related to the investigation of diffusive wrappings. 相似文献
36.
Arianna Manini Antonia Ratti Alberto Brusati Alessio Maranzano Isabella Fogh Silvia Peverelli Stefano Messina Davide Gentilini Federico Verde Barbara Poletti Claudia Morelli Vincenzo Silani Nicola Ticozzi 《International journal of molecular sciences》2022,23(16)
The transmembrane protein 106B (TMEM106B) gene is a susceptibility factor and disease modifier of frontotemporal dementia, but few studies have investigated its role in amyotrophic lateral sclerosis. The aim of this work was to assess the impact of the TMEM106B rs1990622 (A–major risk allele; G–minor allele) on phenotypic variability of 865 patients with amyotrophic lateral sclerosis. Demographic and clinical features were compared according to genotypes by additive, dominant, and recessive genetic models. Bulbar onset was overrepresented among carriers of the AA risk genotype, together with enhanced upper motor neuron involvement and poorer functional status in patients harboring at least one major risk allele (A). In a subset of 195 patients, we found that the homozygotes for the minor allele (GG) showed lower scores at the Edinburgh Cognitive and Behavioral Amyotrophic Lateral Sclerosis Screen, indicating a more severe cognitive impairment, mainly involving the amyotrophic lateral sclerosis-specific cognitive functions and memory. Moreover, lower motor neuron burden predominated among patients with at least one minor allele (G). Overall, we found that TMEM106B is a disease modifier of amyotrophic lateral sclerosis, whose phenotypic effects encompass both sites of onset and functional status (major risk allele), motor functions (both major risk and minor alleles), and cognition (minor allele). 相似文献
37.
Cellular communication and the transfer of information from one cell to another is crucial for cell viability and homeostasis. During the last decade, tunneling nanotubes (TNTs) have attracted scientific attention, not only as a means of direct intercellular communication, but also as a possible system to transport biological cargo between distant cells. Peculiar TNT characteristics make them both able to increase cellular survival capacities, as well as a potential target of neurodegenerative disease progression. Despite TNT formation having been documented in a number of cell types, the exact mechanisms triggering their formation are still not completely known. In this review, we will summarize and highlight those studies focusing on TNT formation in the nervous system, as well as their role in neurodegenerative diseases. Moreover, we aim to stress some possible mechanisms and important proteins probably involved in TNT formation in the nervous system. 相似文献
38.
Giacomini M. Ruggiero C. Bertone S. Calegari L. 《IEEE transactions on bio-medical engineering》1997,44(12):1185-1191
The traditional approach to biochemical identification of marine fresh isolates requires considerably long culture preparation times and large quantities of expensive materials and reagents, and the results are not very reliable. On the other hand, taxonomy tests based on DNA composition, although sensitive and reliable, require long execution times and high costs, A method is presented for the classification of fatty-acid profiles, extracted from marine bacteria strains, at genus level based on supervised artificial neural networks. The proposed method allows the correct identification of all patterns belonging to the training set and almost all patterns belonging to the test set. Moreover, a quantitative measure of the importance of each fatty acid for bacterial classification is also achieved. This measure allows the determination of a cluster of fatty acids to be controlled with greater care. The results show that the proposed method is reproducible and rapid, so that it can be routinely used in the marine microbiology laboratory to identify fresh isolates 相似文献
39.
Marco Lombardo Michel Chiarucci Arianna Quintavalla Claudio Trombini 《Advanced Synthesis \u0026amp; Catalysis》2009,351(17):2801-2806
The ion‐tagged diphenylprolinol silyl ether 6 very efficiently catalyzes the asymmetric Michael addition of aliphatic aldehydes to nitroalkenes with ee of up to>99.5% at low catalyst loadings (0.25–5 mol%) and using only a slight excess of aldehydes (1.2–2 equiv.). This new organocatalyst can be used with the same outstanding efficiency in a wide variety of solvents and reaction conditions. 相似文献
40.
In this paper, a novel multinode wireless monitoring platform, based on ZigBee communication standard, is presented and tested in vivo. The transmission power levels needed to establish a reliable connection from the different gastrointestinal districts are reported and compared with safety levels from international guidelines. These findings can be useful to evaluate the effectiveness of a commercial and standardized approach to implantable and miniaturized monitoring of physiological parameters. 相似文献