Comment on Y. Couder and E. Fort: "Single-Particle Diffraction and Interference at a Macroscopic Scale", Phys. Rev. Lett. (2006)

In a paper from 2006, Couder and Fort [1] describe a version of the famous double slit experiment performed with drops bouncing on a vibrated fluid surface, where interference in the particle statistics is found even though it is possible to determine unambiguously which slit the "walking" drop passes. It is one of the first papers in an impressive series, showing that such walking drops closely resemble de Broglie waves and can reproduce typical quantum phenomena like tunneling and quantized states [2-13]. The double slit experiment is, however, a more stringent test of quantum mechanics, because it relies upon superposition and phase coherence. In the present comment we first point out that the experimental data presented in [1] are not convincing, and secondly we argue that it is not possible in general to capture quantum mechanical results in a system, where the trajectory of the particle is well-defined.Comment: 4 pages, 1 figur

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'Magic coins' and 'magic squares': the discovery of astrological sigils in the Oldenburg Letters

Enclosed in a 1673 letter to Henry Oldenburg were two drawings of a series of astrological sigils, coins and amulets from the collection of Strasbourg mathematician Julius Reichelt (1637–1719). As portrayals of particular medieval and early modern sigils are relatively rare, this paper will analyse the role of these medals in medieval and early modern medicine, the logic behind their perceived efficacy, and their significance in early modern astrological and cabalistic practice. I shall also demonstrate their change in status in the late seventeenth century from potent magical healing amulets tied to the mysteries of the heavens to objects kept in a cabinet for curiosos. The evolving perception of the purpose of sigils mirrored changing early modern beliefs in the occult influences of the heavens upon the body and the natural world, as well as the growing interests among virtuosi in collecting, numismatics and antiquities

Custom Integrated Circuits

Contains reports on nine research projects.Analog Devices, Inc.International Business Machines, Inc.Joint Services Electronics Program (Contract DAALO03-86-K-0002)U.S. Air Force - Office of Scientific Research (Grant AFOSR 86-0164)Rockwell International CorporationOKI SemiconductorU.S. Navy - Office of Naval Research (Contract N00014-81-K-0742)Charles Stark Draper LaboratoryDARPA/U.S. Navy - Office of Naval Research (Contract N00014-80-C-0622)DARPA/U.S. Navy - Office of Naval Research (Contract N00014-87-K-0825)National Science Foundation (Grant ECS-83-10941)AT&T Bell Laboratorie

Exploring the Gantt chart as a tool to highlight double report in case series published during the first wave of the COVID-19 pandemic

Background: During the COVID-19 pandemic, some studies describing diferent aspects of the infection included very similar participants, rising suspicion about double reporting. We aimed to evaluate the Gantt chart as a tool to highlight possible double reporting. The chart is routinely used in business applications to depict tasks of a project, by plotting horizontal bars against time, showing their time span and overlaps. Methods: All case reports and case series of pregnant women with COVID-19, published by July 15, 2020, were included. Initial and final dates of participants’ enrollment, country, city, hospital, and number of pregnancies were plotted in the Gantt chart. Bars stand for enrollment dates of each study, according to hospital and city, thus allowing comparisons. Results: We included 116 articles in the present analysis. The Gantt chart highlighted papers in which some participants were likely the same, thus allowing easier identifcation of double reporting of cases. Combining all information and pregnancy characteristics and outcomes helped to recognize duplications when the authors did not acknowledged the previous publication. Conclusions: Unintended double reporting may occur, especially in exceptional times. The Gantt chart may help researchers to visually identify potential duplications, thus avoiding biased estimates in systematic reviews or meta-analysis

Low gestational weight gain in obese women and pregnancy outcomes

Obesity during pregnancy and excessive weight gain during this period are associated with several maternal–fetal and neonatal complications. Moreover, a significant percentage of women have weight retention in the postpartum period, especially those with excessive weight gain during pregnancy. The recommendations of the 2009 Institute of Medicine were based on observational studies that have consistently shown that women with weight gain within the recommended range had better outcomes during pregnancy. In patients with obesity, however, there is no recommendation for weight gain, according to the class of obesity. This review, therefore, aims to evaluate the evidence on key maternal and fetal complications related to low weight gain during pregnancy in obese and overweight patients

Custom Integrated Circuits

Contains reports on nine research projects.Analog Devices, Inc.International Business Machines CorporationJoint Services Electronics Program Contract DAAL03-89-C-0001U.S. Air Force - Office of Scientific Research Contract AFOSR 86-0164BDuPont CorporationNational Science Foundation Grant MIP 88-14612U.S. Navy - Office of Naval Research Contract N00014-87-K-0825American Telephone and TelegraphDigital Equipment CorporationNational Science Foundation Grant MIP 88-5876