O papel da metafísica na metafísica da ciência: entre o a priori e o naturalizado

SEMINÁRIO PERMANENTE DE FILOSOFIA DAS CIÊNCIAS

03/10/2023, 16:00 - 18:00 (WEST - Western European Summer Time)

SALA 8.2.17 E VIDEOCONFERÊNCIA

The role of metaphysics in Metaphysics of Science: between the a priori and the naturalized

ORADOR: Vanesa Triviño (Universidad Complutense de Madrid)

ORGANIZAÇÃO: João Luís Cordovil, Silvia Di Marco

5.º SEMINÁRIO CONJUNTO “SEMINÁRIO PERMANENTE DE FILOSOFIA DAS CIÊNCIAS / REDE IBÉRICA DE FILOSOFIA DAS CIÊNCIAS (ReIFiCi)”

Abstract

The debate in Metaphysics of Science concerning the interaction that takes place between metaphysics and science has been mainly approached from the perspective of the scientific discipline of physics. In this presentation, I address this debate from a different perspective by paying attention to the biological framework and the different forms in which philosophers use metaphysics when addressing conceptual biological problems. In doing so, I argue that the type of metaphysics that interacts with science when characterizing the ontological status of the world does not seem to coincide with either of the characterizations of metaphysics given in the Metaphysics of Science debate, namely the a priori and the naturalized one. As I will consider, one of the lessons that can be obtained from the field of Metaphysics of Biology, is that a different form of metaphysics seems to be operating in the interaction between metaphysics and science, i.e., applied metaphysics.

Nota biográfica

Vanessa Triviño is an Assistant Professor at the Complutense University of Madrid. She completed her Ph.D. in 2019, focusing on inquiries related to the Metaphysics of Biology, such as the concepts of fitness, holobionts, and biological species. During her doctoral studies, she undertook research residencies at the Konrad Lorenz Institute (Klosterneuburg, Austria) and Egenis: the Centre for the Study of the Life Sciences (Exeter, England). Presently, her research centers on metametaphysical inquiries, metaphysics of science, metaphysics of biology, and feminist metaphysics. Her work delves into questions emerging from metaphysical characterization and the interplay between metaphysics and science in a broader sense, with a specific emphasis on the relationship between metaphysics and biology. Moreover, she examines theories of process metaphysics, properties, and relations to explore their potential applications and contributions to the philosophy of biology and the categorization of sexual differentiation.

Informações

O seminário será realizado presencialmente, na sala 8.2.17, mas será possível assistir também em videoconferência, via Zoom.

Link Zoom

https://videoconf-colibri.zoom.us/j/93642061648?pwd=MHhtTFFudXZpMmo1QVB0emQ3dENIdz09

Morada sala 8.2.17

Faculdade de Ciências da Universidade de Lisboa

Edifício C8, Piso 2

Campo Grande, Lisboa

Contacto

cfculcomunica@fc.ul.pt

Um close-up de nanomáquinas biológicas: mero acaso, fortuita necessidade ou design inteligente?

Structure of the peroxisomal Pex1/Pex6 ATPase complex bound to a substrate

Maximilian Rüttermann, Michelle Koci, Pascal Lill, Ermis Dionysios Geladas, Farnusch Kaschani, Björn Udo Klink, Ralf Erdmann & Christos Gatsogiannis 

Nature Communications volume 14, Article number: 5942 (2023)

 

Fig. 1: Cryo-EM structure of the peroxisomal ATPase Pex1/Pex6.

Abstract

The double-ring AAA+ ATPase Pex1/Pex6 is required for peroxisomal receptor recycling and is essential for peroxisome formation. Pex1/Pex6 mutations cause severe peroxisome associated developmental disorders. Despite its pathophysiological importance, mechanistic details of the heterohexamer are not yet available. Here, we report cryoEM structures of Pex1/Pex6 from Saccharomyces cerevisiae, with an endogenous protein substrate trapped in the central pore of the catalytically active second ring (D2). Pairs of Pex1/Pex6(D2) subdomains engage the substrate via a staircase of pore-1 loops with distinct properties. The first ring (D1) is catalytically inactive but undergoes significant conformational changes resulting in alternate widening and narrowing of its pore. These events are fueled by ATP hydrolysis in the D2 ring and disengagement of a “twin-seam” Pex1/Pex6(D2) heterodimer from the staircase. Mechanical forces are propagated in a unique manner along Pex1/Pex6 interfaces that are not available in homo-oligomeric AAA-ATPases. Our structural analysis reveals the mechanisms of how Pex1 and Pex6 coordinate to achieve substrate translocation.

FREE PDF GRATIS: Nature Communications Sup. Info.

Miller-Urey, nós temos um problema sério: abordagens experimentais mais diferenciadas são necessárias.

Progress in Lipid Research

Volume 92, November 2023, 101253

The fats of the matter: Lipids in prebiotic chemistry and in origin of life studies

Author Tania C.B. Santos, Anthony H. Futerman

Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel

Received 3 July 2023, Revised 30 August 2023, Accepted 30 August 2023, Available online 1 September 2023, Version of Record 12 September 2023.

https://doi.org/10.1016/j.plipres.2023.101253

The Miller-Urey experiment (now located at UCSD, San Diego) that was used to demonstrate the synthesis of biologically relevant molecules in a hypothetical primitive reducing atmosphere.

Image/Imagem 

Abstract

The unique biophysical and biochemical properties of lipids render them crucial in most models of the origin of life (OoL). Many studies have attempted to delineate the prebiotic pathways by which lipids were formed, how micelles and vesicles were generated, and how these micelles and vesicles became selectively permeable towards the chemical precursors required to initiate and support biochemistry and inheritance. Our analysis of a number of such studies highlights the extremely narrow and limited range of conditions by which an experiment is considered to have successfully modeled a role for lipids in an OoL experiment. This is in line with a recent proposal that bias is introduced into OoL studies by the extent and the kind of human intervention. It is self-evident that OoL studies can only be performed by human intervention, and we now discuss the possibility that some assumptions and simplifications inherent in such experimental approaches do not permit determination of mechanistic insight into the roles of lipids in the OoL. With these limitations in mind, we suggest that more nuanced experimental approaches than those currently pursued may be required to elucidate the generation and function of lipids, micelles and vesicles in the OoL.

Abbreviations

CoA coenzyme A DPPC1, 2-dipalmitoyl-sn-glycero-3-phosphocholine GARD graded autocatalysis replication domain Kinrate of incorporation into a micelle Kout rate of exit from a micelle OoL origin of life PA phosphatidic acid PC phosphatidylcholine PE phosphatidylethanolamine PG phosphatidylglycerol POPC1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine PS phosphatidylserine Ps permeability coefficient R-GARD GARD with real lipids SDS sodium dodecyl sulfate SM sphingomyelin

FREE PDF: Progress in Lipid Research

Como, quando e por que a ciência falha em autocorrigir-se???

ABOUT THIS WEBSITE

This academic blog is related to the NanoBubbles project, led by 4 researchers from the Universities of Paris Sorbonne Nord, Maastricht, Grenoble-Alpes and Radboud, in collaboration with researchers from the CNRS, the University of Twente, IRIT and Ecole des Ponts.

The project focuses on how, when and why science fails to correct itself. To understand how the correction of science works or fails, the NanoBubbles project combines approaches from the natural sciences, engineering (natural language processing) and humanities and social sciences (linguistics, sociology, philosophy and history of science). 

The purpose of this academic blog is to communicate on the work carried out within the scope of the project, with the aim of sharing it with a wide audience in line with the principles of open science.

Mais uma hipótese sobre a origem da vida...

Electron transport chains as a window into the earliest stages of evolution

Aaron D. Goldman, Jessica M. Weber, Douglas E. LaRowe, and Laura M. Barge 

Edited by Donald Canfield, Syddansk Universitet, Odense M., Denmark; received September 29, 2022; accepted July 8, 2023

August 14, 2023

120 (34) e2210924120

https://doi.org/10.1073/pnas.2210924120

Abstract

The origin and early evolution of life is generally studied under two different paradigms: bottom up and top down. Prebiotic chemistry and early Earth geochemistry allow researchers to explore possible origin of life scenarios. But for these “bottom–up” approaches, even successful experiments only amount to a proof of principle. On the other hand, “top–down” research on early evolutionary history is able to provide a historical account about ancient organisms, but is unable to investigate stages that occurred during and just after the origin of life. Here, we consider ancient electron transport chains (ETCs) as a potential bridge between early evolutionary history and a protocellular stage that preceded it. Current phylogenetic evidence suggests that ancestors of several extant ETC components were present at least as late as the last universal common ancestor of life. In addition, recent experiments have shown that some aspects of modern ETCs can be replicated by minerals, protocells, or organic cofactors in the absence of biological proteins. Here, we discuss the diversity of ETCs and other forms of chemiosmotic energy conservation, describe current work on the early evolution of membrane bioenergetics, and advocate for several lines of research to enhance this understanding by pairing top–down and bottom–up approaches.

FREE PDF GRATIS: PNAS Sup. Info.