124 research outputs found
Realism and the wave-function
Realism -- the idea that the concepts in physical theories refer to 'things'
existing in the real world -- is introduced as a tool to analyze the status of
the wave-function. Although the physical entities are recognized by the
existence of invariant quantities, examples from classical and quantum physics
suggest that not all the theoretical terms refer to the entities: some terms
refer to properties of the entities, and some terms have only an epistemic
function. In particular, it is argued that the wave-function may be written in
terms of classical non-referring and epistemic terms. The implications for
realist interpretations of quantum mechanics and on the teaching of quantum
physics are examined.Comment: No figure
Abelian gauge potentials on cubic lattices
The study of the properties of quantum particles in a periodic potential
subject to a magnetic field is an active area of research both in physics and
mathematics; it has been and it is still deeply investigated. In this review we
discuss how to implement and describe tunable Abelian magnetic fields in a
system of ultracold atoms in optical lattices. After discussing two of the main
experimental schemes for the physical realization of synthetic gauge potentials
in ultracold set-ups, we study cubic lattice tight-binding models with
commensurate flux. We finally examine applications of gauge potentials in
one-dimensional rings.Comment: To appear on: "Advances in Quantum Mechanics: Contemporary Trends and
Open Problems", G. Dell'Antonio and A. Michelangeli eds., Springer-INdAM
series 201
O conceito de “Dispositivo universal” (Universalapparat) em Günther Anders
Encontra-se em curso, sensivelmente no último meio século, a finalização de um
processo de planetarização da Tecnologia, que, na ordem das causas, terá sido mais proximamente
determinado pela Globalização político-económica urdida e imposta pelo Neoliberalismo e mais
remotamente influenciado por sucessivas revoluções industriais, desde o século XVIII. Ele implicou
uma transformação na própria natureza da Tecnologia, fazendo com que deixasse de ser mero meio
(utensílio, ferramenta, instrumento) para determinados fins e se tivesse tornado num ambiente vital
e existencial. Günther Anders foi um atento e perspicaz observador e crítico desse fenómeno, que, no
seu jargão, concebeu como o do advento de um “Dispositivo universal” (Universalapparat). Dedica-se
a primeira parte deste artigo à releitura da interpretação que esse filósofo alemão fez da sua suposta
génese e evolução. Na segunda parte, analisa-se esse conceito. Explora-se, na terceira parte, duas
consequências filosóficas maiores desse fenómeno.More or less in the last half century, a process of planetarization of Technology is
underway, which in the order of causes will have been more directly determined by the politicaleconomic Globalization woven and imposed by the so-called Neoliberalism and more remotely
influenced by successive industrial revolutions since the 18th century. It implied a transformation in
the nature of Technology, ceasing to be a mere means (utensil, tool, instrument) for certain purposes
and becoming a vital and existential environment. Günther Anders was an attentive, perceptive and
critical observer of this phenomenon that, in his jargon, he conceived as the advent of a “Universal
apparatus” (Universalapparat). I dedicate the first part of this article to reread the German philosopher’s
interpretation of his supposed genesis and evolution. In the second part, I analyze this concept. In the
third part, I explore two main philosophical consequences of this phenomenon
How do parents manage irritability, challenging behavior, non-compliance and anxiety in children with Autism Spectrum Disorders? A meta-synthesis
Although there is increasing research interest in the parenting of children with ASD, at present, little is known about everyday strategies used to manage problem behaviour. We conducted a meta-synthesis to explore what strategies parents use to manage irritability, non-compliance, challenging behaviour and anxiety in their children with ASD. Approaches included: (1) accommodating the child; (2) modifying the environment; (3) providing structure, routine and occupation; (4) supervision and monitoring; (5) managing non-compliance with everyday tasks; (6) responding to problem behaviour; (7) managing distress; (8) maintaining safety and (9) analysing and planning. Results suggest complex parenting demands in children with ASD and problem behaviour. Findings will inform the development of a new measure to quantify parenting strategies relevant to ASD
Chronic Citalopram Administration Causes a Sustained Suppression of Serotonin Synthesis in the Mouse Forebrain
BACKGROUND:Serotonin (5-HT) is a neurotransmitter with important roles in the regulation of neurobehavioral processes, particularly those regulating affect in humans. Drugs that potentiate serotonergic neurotransmission by selectively inhibiting the reuptake of serotonin (SSRIs) are widely used for the treatment of psychiatric disorders. Although the regulation of serotonin synthesis may be an factor in SSRI efficacy, the effect of chronic SSRI administration on 5-HT synthesis is not well understood. Here, we describe effects of chronic administration of the SSRI citalopram (CIT) on 5-HT synthesis and content in the mouse forebrain. METHODOLOGY/PRINCIPAL FINDINGS:Citalopram was administered continuously to adult male C57BL/6J mice via osmotic minipump for 2 days, 14 days or 28 days. Plasma citalopram levels were found to be within the clinical range. 5-HT synthesis was assessed using the decarboxylase inhibition method. Citalopram administration caused a suppression of 5-HT synthesis at all time points. CIT treatment also caused a reduction in forebrain 5-HIAA content. Following chronic CIT treatment, forebrain 5-HT stores were more sensitive to the depleting effects of acute decarboxylase inhibition. CONCLUSIONS/SIGNIFICANCE:Taken together, these results demonstrate that chronic citalopram administration causes a sustained suppression of serotonin synthesis in the mouse forebrain. Furthermore, our results indicate that chronic 5-HT reuptake inhibition renders 5-HT brain stores more sensitive to alterations in serotonin synthesis. These results suggest that the regulation of 5-HT synthesis warrants consideration in efforts to develop novel antidepressant strategies
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