The Moebius topology (twisted, single-sided strip) is intriguing because of its structural elegance and distinct properties. Here we report the generation of block copolymer Moebius strips via a fast self-assembly of chiral block copolymer polystyrene-block-poly(D-lactide acid) (PS-b-PDLA) in tetrahydrofuran/water mixed solvents. The Moebius strip is formed by morphological evolution from large compound micelle (LCM) to spindle-like micelle (SLM) and then to toroid with a 180° twist along the ring. Mechanism insight reveals that a subtle balance of crystallization of PDLA and microphase separation between PS and PDLA chains dominates the formation of Moebius strips. An intriguing helix-helix transition occurs during the chiral transfer from microphase to assemblies, which is driven by relaxation of the internal stress within SLM related to orientated stretching of PS chains. Mesoporous chiral channels can be generated within Moebius strips after removal of PDLA, which are interesting in chiral recognition, separation and asymmetric catalysis.
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http://dx.doi.org/10.1038/s41467-019-11991-3 | DOI Listing |
Rev Colomb Psiquiatr (Engl Ed)
November 2024
Aristotle University of Thessaloniki School of Psychology, S. Kyriakidi 1, Thessaloniki GR 54636, Greece.
Introduction: Do we form mental models which bear an analogical relation to the real world like those of a photograph? Has the language of thought an analogue nature (it makes use of mental imagery) or whether it is exclusively of digital nature like language?
Objectives: The basic aim of the present study is to contribute to the ongoing work on mental imagery by extending the research to an unexplored area that of mental partitioning.
Methods: The present research sample consisted of 498 participants (234 males and 264 females). We used the SPSS software package in order to analyze our data.
Nat Commun
September 2019
Institute of Polymer Science and Engineering, Department of Chemical Engineering, Tsinghua University, Beijing, 100084, China.
The Moebius topology (twisted, single-sided strip) is intriguing because of its structural elegance and distinct properties. Here we report the generation of block copolymer Moebius strips via a fast self-assembly of chiral block copolymer polystyrene-block-poly(D-lactide acid) (PS-b-PDLA) in tetrahydrofuran/water mixed solvents. The Moebius strip is formed by morphological evolution from large compound micelle (LCM) to spindle-like micelle (SLM) and then to toroid with a 180° twist along the ring.
View Article and Find Full Text PDFSoc Sci Med
April 2001
University of Medicine & Dentistry of New Jersey, Stratford 08084, USA.
This article traces the use of managed competition policy to transform the NHS from an administered public service to a set of interlocking markets and contracts. It reviews the overlooked origins of managed competition in the new managerialism and explains the relationship between managed competition and the cost crisis of the NHS by extending Foucault's concept of governmentality to revise the concept of the state. The paper then describes how the government structured health care markets, using managed competition as an instrument of governmentality.
View Article and Find Full Text PDFJ Mol Biol
December 1999
Centre for Drug Design and Development, The University of Queensland, Brisbane, QLD 4072, Australia.
Several macrocyclic peptides ( approximately 30 amino acids), with diverse biological activities, have been isolated from the Rubiaceae and Violaceae plant families over recent years. We have significantly expanded the range of known macrocyclic peptides with the discovery of 16 novel peptides from extracts of Viola hederaceae, Viola odorata and Oldenlandia affinis. The Viola plants had not previously been examined for these peptides and thus represent novel species in which these unusual macrocyclic peptides are produced.
View Article and Find Full Text PDFPsychiatr Clin North Am
September 1988
University of California, Los Angeles.
The lateralization of the cerebral hemispheres constitutes a neuropsychologic parallel to the functioning of the mind. It is proposed that that the dual-track theorem generally and the Siamese-twin configuration (with the Moebius-strip twist) specifically offer a unique and useful paradigmatic perspective that allows us to organize and integrate the characteristics and functions of the brain-mind continuum. A hypothetical "psychology" for the corpus callosum and the two hemispheres was conjectured which would tentatively help to account for some of the brain's behavior, which conceivably approximates that of the mind.
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