23 research outputs found

    Galileo Galilei, Holland and the pendulum clock

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    The pendulum clock was one of the most important metaphors for early modern philosophers. Christiaan Huygens (1629-1695) discovered his pendulum clock in 1656 based on the principle of isochronism discovered by Galileo (1564-1642). This paper aims at exploring the broad historical context of this invention, showing the role of some key figures such as Andreas Colvius (1594-1671), Elia Diodati (1576-1661), Hugo Grotius (1583-1645) and Constantijn Huygens, the father of Christiaan Huygens. Secondly, it suggests - based on this context - that it is hard to believe that Huygens did not know about Galileo’s idea to construct a pendulum regulated clock. Finally, this article illustrates how the Dutch philosopher Spinoza (1632-1677) might have been inspired by Huygens’ discovery of the synchronization of the pendulum clocks in his views on the agreement between bodies in the universe.The pendulum clock was one of the most important metaphors for early modern philosophers. Christiaan Huygens (1629-1695) discovered his pendulum clock in 1656 based on the principle of isochronism discovered by Galileo (1564-1642). This paper aims at exploring the broad historical context of this invention, showing the role of some key figures such as Andreas Colvius (1594-1671), Elia Diodati (1576-1661), Hugo Grotius (1583-1645) and Constantijn Huygens, the father of Christiaan Huygens. Secondly, it suggests - based on this context - that it is hard to believe that Huygens did not know about Galileo’s idea to construct a pendulum regulated clock. Finally, this article illustrates how the Dutch philosopher Spinoza (1632-1677) might have been inspired by Huygens’ discovery of the synchronization of the pendulum clocks in his views on the agreement between bodies in the universe.---Galileo Galilei, Holanda e o relógio de pênduloO relógio de pêndulo foi uma das metáforas mais importantes para os filósofos modernos. Christiaan Huygens (1629-1695) inventou o relógio de pêndulo em 1656 baseado no princípio do isocronismo descoberto por Galileo (1564-1642). Este artigo busca explorar o amplo contexto histórico dessa invenção, demonstrando o papel de algumas figuras-chave como Andreas Colvius (1594-1671), Elia Diodati (1576-1661), Hugo Grotius (1583-1645) e Constantijn Huygens, o pai de Christiaan Huygens. Em segundo lugar, sugere-se - baseado nesse contexto - que é difícil acreditar que Huygens não sabia da ideia de Galileo de construir um relógio regulado por um pêndulo. Por fim, este artigo ilustra como o filósofo holandês Espinosa (1632-1677) pode ter se inspirado nessa invenção de Huygens da sincronização do relógio de pêndulo em suas visões sobre o acordo entre os corpos no universo.---Original em inglês

    Situational judgment tests as a new tool for dental student selection

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    Cognitive tests are used to select students into dental school, yet cognitive predictors explain only part of the variance in academic performance. Therefore, interviews and personality tests are often used to measure noncognitive (e.g., interpersonal) characteristics. Recently, situational judgment tests (SJTs) have drawn attention since there is evidence that SJTs can be valid predictors in medical admission contexts. This study examines the validity of an SJT measuring interpersonal skills for predicting academic performance of dental students. Incremental validity over cognitive tests is also examined. In this study, 796 dental students who passed the admission exam for medical and dental students in Flanders, Belgium, and enrolled in one of the two Flemish dental schools were evaluated. Grade point average (GPA) in the five years of dental studies served as the criterion. Corrected correlation between the cognitive tests of the admission exam and GPA equaled .38. Their validity dropped from .45 (year 1) to .18 (year 5). However, the validity of the SJT increased from .05 (year 1) to .20 (year 5). The SJT had incremental validity in year 5. Dental admissions committees that envision assessing a broad set of capabilities might consider using an SJT as a valuable supplement to cognitive tests. Future research needs to confirm these findings with job performance as another criterion

    Galileo Galilei, Holland and the pendulum clock

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    The pendulum clock was one of the most important metaphors for early modern philosophers. Christiaan Huygens (1629-1695) discovered his pendulum clock in 1656 based on the principle of isochronism discovered by Galileo (1564-1642). This paper aims at exploring the broad historical context of this invention, showing the role of some key figures such as Andreas Colvius (1594-1671), Elia Diodati (1576-1661), Hugo Grotius (1583-1645) and Constantijn Huygens, the father of Christiaan Huygens. Secondly, it suggests - based on this context - that it is hard to believe that Huygens did not know about Galileo’s idea to construct a pendulum regulated clock. Finally, this article illustrates how the Dutch philosopher Spinoza (1632-1677) might have been inspired by Huygens’ discovery of the synchronization of the pendulum clocks in his views on the agreement between bodies in the universe

    The effects of coaching on situational judgment tests in high-stakes selection

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    Although the evidence for the use of situational judgment tests (SJTs) in high-stakes testing has been generally promising, questions have been raised regarding the potential coachability of SJTs. This study reports the first examination of the effects of coaching on SJT scores in an operational high-stakes setting. We contrast findings from a simple comparison of SJT scores for coached and uncoached participants (posttest only) with three different approaches to deal with the effects of self-selection into coaching programs, namely using a pretest as a covariate and using two different forms of propensity score-based matching using a wide range of variables as covariates. Coaching effects were estimated at about 0.5 SDs. The implications for the use of SJTs in high-stakes settings and for coaching research in general are discussed

    Effect of anti-interleukin drugs in patients with COVID-19 and signs of cytokine release syndrome (COV-AID): a factorial, randomised, controlled trial.

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    BACKGROUND: Infections with SARS-CoV-2 continue to cause significant morbidity and mortality. Interleukin (IL)-1 and IL-6 blockade have been proposed as therapeutic strategies in COVID-19, but study outcomes have been conflicting. We sought to study whether blockade of the IL-6 or IL-1 pathway shortened the time to clinical improvement in patients with COVID-19, hypoxic respiratory failure, and signs of systemic cytokine release syndrome. METHODS: We did a prospective, multicentre, open-label, randomised, controlled trial, in hospitalised patients with COVID-19, hypoxia, and signs of a cytokine release syndrome across 16 hospitals in Belgium. Eligible patients had a proven diagnosis of COVID-19 with symptoms between 6 and 16 days, a ratio of the partial pressure of oxygen to the fraction of inspired oxygen (PaO(2):FiO(2)) of less than 350 mm Hg on room air or less than 280 mm Hg on supplemental oxygen, and signs of a cytokine release syndrome in their serum (either a single ferritin measurement of more than 2000 μg/L and immediately requiring high flow oxygen or mechanical ventilation, or a ferritin concentration of more than 1000 μg/L, which had been increasing over the previous 24 h, or lymphopenia below 800/mL with two of the following criteria: an increasing ferritin concentration of more than 700 μg/L, an increasing lactate dehydrogenase concentration of more than 300 international units per L, an increasing C-reactive protein concentration of more than 70 mg/L, or an increasing D-dimers concentration of more than 1000 ng/mL). The COV-AID trial has a 2 × 2 factorial design to evaluate IL-1 blockade versus no IL-1 blockade and IL-6 blockade versus no IL-6 blockade. Patients were randomly assigned by means of permuted block randomisation with varying block size and stratification by centre. In a first randomisation, patients were assigned to receive subcutaneous anakinra once daily (100 mg) for 28 days or until discharge, or to receive no IL-1 blockade (1:2). In a second randomisation step, patients were allocated to receive a single dose of siltuximab (11 mg/kg) intravenously, or a single dose of tocilizumab (8 mg/kg) intravenously, or to receive no IL-6 blockade (1:1:1). The primary outcome was the time to clinical improvement, defined as time from randomisation to an increase of at least two points on a 6-category ordinal scale or to discharge from hospital alive. The primary and supportive efficacy endpoints were assessed in the intention-to-treat population. Safety was assessed in the safety population. This study is registered online with ClinicalTrials.gov (NCT04330638) and EudraCT (2020-001500-41) and is complete. FINDINGS: Between April 4, and Dec 6, 2020, 342 patients were randomly assigned to IL-1 blockade (n=112) or no IL-1 blockade (n=230) and simultaneously randomly assigned to IL-6 blockade (n=227; 114 for tocilizumab and 113 for siltuximab) or no IL-6 blockade (n=115). Most patients were male (265 [77%] of 342), median age was 65 years (IQR 54-73), and median Systematic Organ Failure Assessment (SOFA) score at randomisation was 3 (2-4). All 342 patients were included in the primary intention-to-treat analysis. The estimated median time to clinical improvement was 12 days (95% CI 10-16) in the IL-1 blockade group versus 12 days (10-15) in the no IL-1 blockade group (hazard ratio [HR] 0·94 [95% CI 0·73-1·21]). For the IL-6 blockade group, the estimated median time to clinical improvement was 11 days (95% CI 10-16) versus 12 days (11-16) in the no IL-6 blockade group (HR 1·00 [0·78-1·29]). 55 patients died during the study, but no evidence for differences in mortality between treatment groups was found. The incidence of serious adverse events and serious infections was similar across study groups. INTERPRETATION: Drugs targeting IL-1 or IL-6 did not shorten the time to clinical improvement in this sample of patients with COVID-19, hypoxic respiratory failure, low SOFA score, and low baseline mortality risk. FUNDING: Belgian Health Care Knowledge Center and VIB Grand Challenges program

    Heat in Renaissance Philosophy

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    The term ‘heat’ originates from the Old English word hǣtu, a word of Germanic origin; related to the Dutch ‘hitte’ and German ‘Hitze’. Today, we distinguish three different meanings of the word ‘heat’. First, ‘heat’ is understood in colloquial English as ‘hotness’. There are, in addition, two scientific meanings of ‘heat’. ‘Heat’ can have the meaning of the portion of energy that changes with a change of temperature. And finally, ‘heat’ can have the meaning of the transfer of thermal energy from a hotter to a colder system or body. By contrast, for the Ancients and Scholastics, ‘heat’ was a manifest, real quality of bodies and there was an ontological distinction between biological or innate heat (which was regarded as an innate principle of life for warm-blooded animals) and the physical manifest heat of external objects, which is potentially harmful. During the late Renaissance period, however, both views changed fundamentally and evolved - via the application of physical and mechanical analogies - into the foundations for today’s unified mechanistic theory of heat

    Le «démasquement» de Descartes par Spinoza dans Les Principia Philosophiae Cartesianae

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    Spinoza’s Principles of Cartesian Philosophy is often presented simply as an interpretation of Descartes’ Principia that does not reveal anything significant about Spinoza’s philosophy and its development. This paper, however, shows that Spinoza altered Descartes’ text in a way congruent with what he would later write in his Theological Political Treatise and the Ethics. More precisely, this paper concentrates not on what Spinoza added to Descartes’ texts but on how he presented them. The paper furthermore examines questions that were obviously important for Descartes but absent in Spinoza’s interpretation. Finally, this paper examines two concrete examples to show that Spinoza’s adaptations function as an unmasking of Descartes’ physics
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