Non-perturbative corrections to mean-field behavior: spherical model on spider-web graph

We consider the spherical model on a spider-web graph. This graph is effectively infinite-dimensional, similar to the Bethe lattice, but has loops. We show that these lead to non-trivial corrections to the simple mean-field behavior. We first determine all normal modes of the coupled springs problem on this graph, using its large symmetry group. In the thermodynamic limit, the spectrum is a set of $\delta$-functions, and all the modes are localized. The fractional number of modes with frequency less than $\omega$ varies as $\exp (-C/\omega)$ for $\omega$ tending to zero, where $C$ is a constant. For an unbiased random walk on the vertices of this graph, this implies that the probability of return to the origin at time $t$ varies as $\exp(- C' t^{1/3})$, for large $t$, where $C'$ is a constant. For the spherical model, we show that while the critical exponents take the values expected from the mean-field theory, the free-energy per site at temperature $T$, near and above the critical temperature $T_c$, also has an essential singularity of the type $\exp[ -K {(T - T_c)}^{-1/2}]$.Comment: substantially revised, a section adde

Fluidic gates simulated with lattice Boltzmann method under different Reynolds numbers

© 2018 Elsevier B.V. Fluidic devices use fluid as a medium for information transfer and computation. Boolean values are represented by the presence of fluid jets in the input and output channels. Velocity of a fluid is one of the parameters determining Reynolds number of the flow. Reynolds number is a parameter that characterizes the behaviour of the flow: laminar, transient or turbulent. Using lattice Boltzmann method we study the behaviour of fluidic gates for various Reynolds numbers. On the designs of AND and OR gates we show the fluidic gates remain functional even for low Reynolds numbers, like 100. The gates designed can be cascaded into functional logical circuits

Gender essentialism and occupational segregation in insolvency practice

Advances towards egalitarianism in professional recruitment may be offset by processes of occupational re-segregation. Drawing on gender theory this paper investigates horizontal segregation in the UK insolvency profession, as revealed through the lived experiences of female and male practitioners. It is shown that horizontal segregation pervades at different levels of practice and is undergirded by various elements of gender essentialism. Physical essentialism explains why insolvency practice has been traditionally gendered male. Interactional essentialism combines with the management of work-life balance to define the subfields of corporate and personal insolvency as masculine and feminine respectively. Gender essentialist assumptions also pervade the distribution of roles and the allocation of work tasks. Networks are identified as arenas for the reproduction and perpetuation of occupational segregation. The findings indicate the continuing potency of gender in everyday professional life, the limitations of diversity-orientated policies and the complexities of formulating transformative agendas

Desafios da implementação de estratégias do envelhecimento ativo: caminhos para a promoção á saúde / Challenges of the implementation of active aging strategies: pathways for the promotion of health

Objetivo: Identificar os desafios encontrados que impedem a promoção do envelhecimento ativo da população idosa brasileira, avaliando as estratégias executadas e elencando ações que possam equipar um projeto de envelhecimento ativo. Método: Trata-se de uma Revisão Bibliográfica da Literatura acerca da implementação de estratégias do Envelhecimento Ativo, compreendendo o período de 2000-2018 a fim de que se investigassem as adversidades com minúcia; com busca por artigos científicos disponíveis nas bases de dados Literatura Latino-Americana em Ciências da Saúde (LILACS), Scientific Electronic Library Online (SCIELO) e Literatura Internacional em Ciências da Saúde MEDLINE. Resultados: Através da análise de 30 artigos detectou-se como barreira ao envelhecimento ativo o baixo nível socioeconômico da população, a não aplicação Correta das leis e ao baixo conhecimento dos profissionais da saúde, porém ações com resultados positivos mostram que essa realidade pode ser mudada. Conclusão: O envelhecimento ativo é essencial para a saúde do idoso, e para superar as barreiras de sua concretização na sociedade brasileira, é necessário que os profissionais da saúde se mobilizem pelos direitos dos idosos, em especial a Enfermagem, se capacitando acerca do tema durante e após a graduação, a fim de que essa prática faca parte do comportamento da população. Contribuições e implicações para a Enfermagem: Contribuir para o entendimento da importância do Envelhecimento Ativo para a sociedade e do papel da enfermagem como principal agente de promoção do mesmo, contribuindo com sugestões e estimulando a efetivação do envelhecimento ativo, a fim de que futuramente se gere um bem estar social.

Outcome measurement in functional neurological disorder: a systematic review and recommendations.

OBJECTIVES: We aimed to identify existing outcome measures for functional neurological disorder (FND), to inform the development of recommendations and to guide future research on FND outcomes. METHODS: A systematic review was conducted to identify existing FND-specific outcome measures and the most common measurement domains and measures in previous treatment studies. Searches of Embase, MEDLINE and PsycINFO were conducted between January 1965 and June 2019. The findings were discussed during two international meetings of the FND-Core Outcome Measures group. RESULTS: Five FND-specific measures were identified-three clinician-rated and two patient-rated-but their measurement properties have not been rigorously evaluated. No single measure was identified for use across the range of FND symptoms in adults. Across randomised controlled trials (k=40) and observational treatment studies (k=40), outcome measures most often assessed core FND symptom change. Other domains measured commonly were additional physical and psychological symptoms, life impact (ie, quality of life, disability and general functioning) and health economics/cost-utility (eg, healthcare resource use and quality-adjusted life years). CONCLUSIONS: There are few well-validated FND-specific outcome measures. Thus, at present, we recommend that existing outcome measures, known to be reliable, valid and responsive in FND or closely related populations, are used to capture key outcome domains. Increased consistency in outcome measurement will facilitate comparison of treatment effects across FND symptom types and treatment modalities. Future work needs to more rigorously validate outcome measures used in this population

Magnetic helicity in primordial and dynamo scenarios of galaxies

Some common properties of helical magnetic fields in decaying and driven turbulence are discussed. These include mainly the inverse cascade that produces fields on progressively larger scales. Magnetic helicity also restricts the evolution of the large scale field: the field decays less rapidly than a non-helical field, but it also saturates more slowly, i.e. on a resistive time scale if there are no magnetic helicity fluxes. The former effect is utilized in primordial field scenarios, while the latter is important for successfully explaining astrophysical dynamos that saturate faster than resistively. Dynamo action is argued to be important not only in the galactic dynamo, but also in accretion discs in active galactic nuclei and around protostars, both of which contribute to producing a strong enough seed magnetic field. Although primordial magnetic fields may be too weak to compete with these astrophysical mechanisms, such fields could perhaps still be important in producing polarization effects in the cosmic background radiation.Comment: 8 pages, 5 figures, talk given in Bologna, August 2006, proceedings of "The Origin and Evolution of Cosmic Magnetism", Astron. Nachr. (in press

Observations of the 2019 April 4 Solar Energetic Particle Event at the Parker Solar Probe

A solar energetic particle event was detected by the Integrated Science Investigation of the Sun (IS⊙IS) instrument suite on Parker Solar Probe (PSP) on 2019 April 4 when the spacecraft was inside of 0.17 au and less than 1 day before its second perihelion, providing an opportunity to study solar particle acceleration and transport unprecedentedly close to the source. The event was very small, with peak 1 MeV proton intensities of ~0.3 particles (cm² sr s MeV)⁻¹, and was undetectable above background levels at energies above 10 MeV or in particle detectors at 1 au. It was strongly anisotropic, with intensities flowing outward from the Sun up to 30 times greater than those flowing inward persisting throughout the event. Temporal association between particle increases and small brightness surges in the extreme-ultraviolet observed by the Solar TErrestrial RElations Observatory, which were also accompanied by type III radio emission seen by the Electromagnetic Fields Investigation on PSP, indicates that the source of this event was an active region nearly 80° east of the nominal PSP magnetic footpoint. This suggests that the field lines expanded over a wide longitudinal range between the active region in the photosphere and the corona

Energetic Particle Increases Associated with Stream Interaction Regions

The Parker Solar Probe was launched on 2018 August 12 and completed its second orbit on 2019 June 19 with perihelion of 35.7 solar radii. During this time, the Energetic Particle Instrument-Hi (EPI-Hi, one of the two energetic particle instruments comprising the Integrated Science Investigation of the Sun, IS⊙IS) measured seven proton intensity increases associated with stream interaction regions (SIRs), two of which appear to be occurring in the same region corotating with the Sun. The events are relatively weak, with observed proton spectra extending to only a few MeV and lasting for a few days. The proton spectra are best characterized by power laws with indices ranging from −4.3 to −6.5, generally softer than events associated with SIRs observed at 1 au and beyond. Helium spectra were also obtained with similar indices, allowing He/H abundance ratios to be calculated for each event. We find values of 0.016–0.031, which are consistent with ratios obtained previously for corotating interaction region events with fast solar wind ≤ 600 km s⁻¹. Using the observed solar wind data combined with solar wind simulations, we study the solar wind structures associated with these events and identify additional spacecraft near 1 au appropriately positioned to observe the same structures after some corotation. Examination of the energetic particle observations from these spacecraft yields two events that may correspond to the energetic particle increases seen by EPI-Hi earlier