Realistic Claims in Logical Empiricism

Logical empiricism is commonly seen as a counter-position to scientific realism. In the present paper it is shown that there indeed existed a realist faction within the logical empiricist movement. In particular, I shall point out that at least four types of realistic arguments can be distinguished within this faction: Reichenbach’s ‘probabilistic argument,’ Feigl’s ‘pragmatic argument,’ Hempel’s ‘indispensability argument,’ and Kaila’s ‘invariantist argument.’ All these variations of arguments are intended to prevent the logical empiricist agenda from the shortcomings of radical positivism, instrumentalism, and other forms of scientific antirealism. On the whole, it will be seen that logical empiricism and scientific realism are essentially compatible with each other. Especially Kaila’s invariantist approach to science (and nature) comes quite close to what nowadays is discussed under the label ‘structural realism.’ This, in turn, necessitates a fundamental reevaluation of Kaila’s role in the logical empiricist movement in particular and in twentieth-century philosophy of science in general

Perception in Plato’s Heaven?

American critical realism was defended in two versions, an “essentialist” and an “empirical.” The main proponent of the essentialist version was George Santayana, who in his Scepticism and Animal Faith (1923) outlined a critical realist account of epistemology based substantially on an articulate doctrine of essences. In the present paper, an attempt is made to critically examine the resulting approach, particularly in relation to perception. It will be argued that Santayana failed to develop a sufficiently convincing essentialist view of perception, and that his actual significance in terms of the impact of the critical realist movement was, contrary to what is often claimed, quite limited

Enhancement of Intracellular Calcium Ion Mobilization by Moderately but Not Highly Positive Material Surface Charges

Electrostatic forces at the cell interface affect the nature of cell adhesion and function; but there is still limited knowledge about the impact of positive or negative surface charges on cell-material interactions in regenerative medicine. Titanium surfaces with a variety of zeta potentials between −90 mV and +50 mV were generated by functionalizing them with amino polymers, extracellular matrix proteins/peptide motifs and polyelectrolyte multilayers. A significant enhancement of intracellular calcium mobilization was achieved on surfaces with a moderately positive (+1 to +10 mV) compared with a negative zeta potential (−90 to −3 mV). Dramatic losses of cell activity (membrane integrity, viability, proliferation, calcium mobilization) were observed on surfaces with a highly positive zeta potential (+50 mV). This systematic study indicates that cells do not prefer positive charges in general, merely moderately positive ones. The cell behavior of MG-63s could be correlated with the materials’ zeta potential; but not with water contact angle or surface free energy. Our findings present new insights and provide an essential knowledge for future applications in dental and orthopedic surgery. © Copyright © 2020 Gruening, Neuber, Nestler, Lehnfeld, Dubs, Fricke, Schnabelrauch, Helm, Müller, Staehlke and Nebe

Mathematik in der Tradition des Neukantianismus / Siegener Beiträge zur Geschichte und Philosophie der Mathematik 2019

Enthält nicht nur Beiträge der internationalen Tagung "Mathematik in der Tradition des Neukantianismus" an der Universität Siegen, Emmy-Noether-Campus, 15.-16.3.2018"Mathematik in der Tradition des Neukantianismus" war das Thema einer internationalen Tagung, die im März 2018 in Siegen stattfand. Dass die Philosophie der Mathematik für die Autoren dieser Denktradition ein zentrales Anliegen war, ist einerseits selbstverständlich. Spielt doch bereits für Kant das ’Phänomen Mathematik’ in vielerlei Hinsicht eine Schlüsselrolle. Auf der anderen Seite werden der historische Blick auf das frühe 20. Jahrhundert wie auch die aktuellen Überlegungen zur Philosophie der Mathematik dominiert von Autoren analytischer Prägung. Der erste Teil des Bandes enthält die Tagungsbeiträge. Drei weitere Beiträge zu Kurt Gödel, Nikolaus Cusanus und Heinrich Behmann runden die farbenfrohe Palette dieser Siegener Beiträge ab.Inhalt: Mathematik in der Tradition des Neukantianismus: Gottfried Gabriel & Sven Schlotter: Freges Philosophie der Mathematik im Kontext des Neukantianismus Kay Herrmann: Leonard Nelson: Mathematische Erkenntnis als synthetisches Apriori Daniel Koenig: Ernst Cassirer und der mathematische Raum – vom Erkenntnisproblem zum Symbolproblem Thomas Mormann: Mathematische Wissenschaftsphilosophie im Marburger Neukantianismus Matthias Neuber: Cassirer, der Grundlagenstreit und die „idealen Elemente“ der Mathematik Shafie Shokrani: Die Philosophie der Mathematik und die Sokratische Methode Leonard Nelsons – Ein Überblick Siegener Beiträge zur Geschichte und Philosophie der Mathematik: Merlin Carl & Eva-Maria Engelen: Einige Bemerkungen Kurt Gödels zur Mengenlehre Gregor Nickel: Nec finitum – nec infinitum. Überlegungen zur Rolle der Mathematik in der Kosmologie des Nikolaus Cusanus Christian Thiel: Heinrich Behmanns Beitrag zur Grundlagendebatt

A comprehensive in situ and remote sensing data set from the Arctic CLoud Observations Using airborne measurements during polar Day (ACLOUD) campaign

The Arctic CLoud Observations Using airborne measurements during polar Day (ACLOUD) campaign was carried out north-west of Svalbard (Norway) between 23 May and 6 June 2017. The objective of ACLOUD was to study Arctic boundary layer and mid-level clouds and their role in Arctic amplification. Two research aircraft (Polar 5 and 6) jointly performed 22 research flights over the transition zone between open ocean and closed sea ice. Both aircraft were equipped with identical instrumentation for measurements of basic meteorological parameters, as well as for turbulent and radiative energy fluxes. In addition, on Polar 5 active and passive remote sensing instruments were installed, while Polar 6 operated in situ instruments to characterize cloud and aerosol particles as well as trace gases. A detailed overview of the specifications, data processing, and data quality is provided here. It is shown that the scientific analysis of the ACLOUD data benefits from the coordinated operation of both aircraft. By combining the cloud remote sensing techniques operated on Polar 5, the synergy of multi-instrument cloud retrieval is illustrated. The remote sensing methods were validated using truly collocated in situ and remote sensing observations. The data of identical instruments operated on both aircraft were merged to extend the spatial coverage of mean atmospheric quantities and turbulent and radiative flux measurement. Therefore, the data set of the ACLOUD campaign provides comprehensive in situ and remote sensing observations characterizing the cloudy Arctic atmosphere. All processed, calibrated, and validated data are published in the World Data Center PANGAEA as instrument-separated data subsets (Ehrlich et al., 2019b, https://doi.org/10.1594/PANGAEA.902603)

A comprehensive in situ and remote sensing data set from the Arctic CLoud Observations Using airborne measurements during polar Day (ACLOUD) campaign

The Arctic CLoud Observations Using airborne measurements during polar Day (ACLOUD) cam- paign was carried out north-west of Svalbard (Norway) between 23 May and 6 June 2017. The objective of ACLOUD was to study Arctic boundary layer and mid-level clouds and their role in Arctic amplification. Two research aircraft (Polar 5 and 6) jointly performed 22 research flights over the transition zone between open ocean and closed sea ice. Both aircraft were equipped with identical instrumentation for measurements of basic meteorological parameters, as well as for turbulent and radiative energy fluxes. In addition, on Polar 5 active and passive remote sensing instruments were installed, while Polar 6 operated in situ instruments to characterize cloud and aerosol particles as well as trace gases. A detailed overview of the specifications, data processing, and data quality is provided here. It is shown that the scientific analysis of the ACLOUD data benefits from the coordinated operation of both aircraft. By combining the cloud remote sensing techniques operated on Polar 5, the synergy of multi-instrument cloud retrieval is illustrated. The remote sensing methods were validated us- ing truly collocated in situ and remote sensing observations. The data of identical instruments operated on both aircraft were merged to extend the spatial coverage of mean atmospheric quantities and turbulent and radiative flux measurement. Therefore, the data set of the ACLOUD campaign provides comprehensive in situ and remote sensing observations characterizing the cloudy Arctic atmosphere. All processed, calibrated, and validated data are published in the World Data Center PANGAEA as instrument-separated data subsets (Ehrlich et al., 2019b, https://doi.org/10.1594/PANGAEA.902603)