Dissipative effects in the effective field theory of inflation

We generalize the effective field theory of single clock inflation to include dissipative effects. Working in unitary gauge we couple a set of composite operators, Oµν..., in the effective action which is constrained solely by invariance under time-dependent spatial diffeomorphisms. We restrict ourselves to situations where the degrees of freedom responsible for dissipation do not contribute to the density perturbations at late time. The dynamics of the perturbations is then modified by the appearance of ‘friction’ and noise terms, and assuming certain locality properties for the Green’s functions of these composite operators, we show that there is a regime characterized by a large friction term γ ≫ H in which the ζ-correlators are dominated by the noise and the power spectrum can be significantly enhanced. We also compute the three point function hζζζi for a wide class of models and discuss under which circumstances large friction leads to an increased level of non-Gaussianities. In particular, under our assumptions, we show that strong dissipation together with the required non-linear realization of the symmetries implies |fNL| ∼ γ c 2 sH ≫ 1. As a paradigmatic example we work out a variation of the ‘trapped inflation’ scenario with local response functions and perform the matching with our effective theory. A detection of the generic type of signatures that result from incorporating dissipative effects during inflation, as we describe here, would teach us about the dynamics of the early universe and also extend the parameter space of inflationary modelsFil: Lopez Nacir, Diana Laura. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Porto, Rafael A.. Institute For Advanced Study; Estados Unidos. Columbia University; Estados UnidosFil: Senatore, Leonardo. University of Stanford. Physics Department; Estados Unidos. Institute For Advanced Study; Estados UnidosFil: Zaldarriaga, Matias. Institute For Advanced Study; Estados Unido

A Simple Gaze Tracker for Computer Operation by the Disabled in Education

A compact gaze tracker was developed which consists of a head band and electrodes which process the Electro-Oculo-Gram (EOG) reflecting the patient´s eye movements. We have confirmed that the processed EOG signal correlates well with gaze angle, and we show that the instrument we designed enables a child to move a target on a screen up to 40 degrees left-right from central sight. To achieve this, a signal processing circuit was designed and placed on a head band to minimize noise. Further processing is based on the identification of saccadic eye movements and on the educated calculation of the estimated gaze angle as a result of angle change in both directions. A 75% success rate was achieved to detect transitions of eye positions in 5° steps from +40° to -40°. First tests by normal children suggest that the device may prove useful for communication by the disabled (e.g. patients with no control on hand movements). In such cases, extensive personal training will tap on neurological plasticity to achieve the required performance level for computer mouse command of educational games and for interactive applications in general

A Simple Gaze Tracker for Computer Operation by the Disabled in Education

A compact gaze tracker was developed which consists of a head band and electrodes which process the Electro-Oculo-Gram (EOG) reflecting the patient´s eye movements. We have confirmed that the processed EOG signal correlates well with gaze angle, and we show that the instrument we designed enables a child to move a target on a screen up to 40 degrees left-right from central sight. To achieve this, a signal processing circuit was designed and placed on a head band to minimize noise. Further processing is based on the identification of saccadic eye movements and on the educated calculation of the estimated gaze angle as a result of angle change in both directions. A 75% success rate was achieved to detect transitions of eye positions in 5° steps from +40° to -40°. First tests by normal children suggest that the device may prove useful for communication by the disabled (e.g. patients with no control on hand movements). In such cases, extensive personal training will tap on neurological plasticity to achieve the required performance level for computer mouse command of educational games and for interactive applications in general.Um rastreador visual compacto que foi desenvolvido consiste numa faixa para a cabeça com eletrodos que processam o Electro-Oculo-Gram (EOG), acompanhando o movimento do olhar do paciente. Confi rmamos que o sinal processado pelo EOG correlaciona-se muito bem com o ângulo do olhar, e nos mostra que o instrumento projetado possibilita a criança mover o alvo na tela de 40º esquerda-direita da vista central. Para isso, um circuito de processamento de sinal foi projetado e colocado em uma faixa de cabeça para minimizar ruídos. O processamento adicional foi baseado na identifi cação dos movimentos oculares e o cálculo estimado do ângulo da faixa resultaram na mudança do ângulo em ambas as direções. Uma taxa de 75% de sucesso foi alcançada na detecção das posições do olho numa escala de 5º desde +40º até -40º. Os primeiros testes em crianças sem defi ciência indicam que o dispositivo pode ser viável para comunicação de pessoas com defi ciência (ex. sujeitos que não tem controle dos movimentos das mãos). Nesses casos, o treinamento extensivo de profi ssionais poderá alcançar a plasticidade neurológica requerida para comandar o mouse do computador dos jogos educacionais e aplicações interativas em geral

Chemical composition and phytotoxic effects of essential oils of Salvia hierosolymitana Boiss. and Salvia multicaulis Vahl. var. simplicifolia Boiss. growing wild in Lebanon

The chemical composition of the essential oils of S. hierosolymitana Boiss. and S. multicaulis Vahl. var. simplicifolia Boiss. collected in Lebanon was studied by means of GC and GC-MS analysis. In all 115 compounds were identified: 82 for S hierosolymitana and 72 for S. multicaulis var. simplicifolia. The presence of carbonylic compounds (17%) characterizes the oil from S. hierosolymitana,while S. multicaulis var. simplicifolia oil is rich of monoterpenes (34.5%) and sesquiterpenes (46.9%). The effects of the essential oils on germination and initial radical elongation of Raphanus sativus L. (radish) and Lepidium sativum L. (garden cress) were studied, indicating in a different activity against radical elongation of the species tested

Chemical composition and phytotoxic effects of essential oils of Salvia hierosolymitana Boiss. and Salvia multicaulis Vahl. var. simplicifolia Boiss. growing wild in Lebanon

The chemical composition of the essential oils of S. hierosolymitana Boiss. and S. multicaulis Vahl. var. simplicifolia Boiss. collected in Lebanon was studied by means of GC and GC-MS analysis. In all 115 compounds were identified: 82 for S hierosolymitana and 72 for S. multicaulis var. simplicifolia. The presence of carbonylic compounds (17%) characterizes the oil from S. hierosolymitana,while S. multicaulis var. simplicifolia oil is rich of monoterpenes (34.5%) and sesquiterpenes (46.9%). The effects of the essential oils on germination and initial radical elongation of Raphanus sativus L. (radish) and Lepidium sativum L. (garden cress) were studied, indicating in a different activity against radical elongation of the species tested

Electromechanical and robotic devices for gait and balance rehabilitation of children with neurological disability: a systematic review

In the last two decades, a growing interest has been focused on gait and balance robot-assisted rehabilitation in children with neurological disabilities. Robotic devices allow the implementation of intensive, task-specific training fostering functional recovery and neuroplasticity phenomena. However, limited attention has been paid to the protocols used in this research framework. This systematic review aims to provide an overview of the existing literature on robotic systems for the rehabilitation of gait and balance in children with neurological disabilities and their rehabilitation applications. The literature search was carried out independently and synchronously by three authors on the following databases: MEDLINE, Cochrane Library, PeDro, Institute of Electrical and Electronics Engineers, ScienceDirect, and Google Scholar. The data collected included three subsections referring to clinical, technical, and regulatory aspects. Thirty-one articles out of 81 found on the primary literature search were included in the systematic review. Most studies involved children with cerebral palsy. Only one-third of the studies were randomized controlled trials. Overall, 17 devices (nine end-effector systems and eight exoskeletons) were investigated, among which only 4 (24%) were bore the CE mark. Studies differ on rehabilitation protocols duration, intensity, and outcome measures. Future research should improve both rehabilitation protocols\u2019 and devices\u2019 descriptions

Effects of robotic upper limb treatment after stroke on cognitive patterns: A systematic review

Background: Robotic therapy (RT) has been internationally recognized for the motor rehabilitation of the upper limb. Although it seems that RT can stimulate and promote neuroplasticity, the effectiveness of robotics in restoring cognitive deficits has been considered only in a few recent studies. Objective: To verify whether, in the current state of the literature, cognitive measures are used as inclusion or exclusion criteria and/or outcomes measures in robotic upper limb rehabilitation in stroke patients. Methods: The systematic review was conducted according to PRISMA guidelines. Studies eligible were identified through PubMed/MEDLINE and Web of Science from inception to March 2021. Results: Eighty-one studies were considered in this systematic review. Seventy-three studies have at least a cognitive inclusion or exclusion criteria, while only seven studies assessed cognitive outcomes. Conclusion: Despite the high presence of cognitive instruments used for inclusion/exclusion criteria their heterogeneity did not allow the identification of a guideline for the evaluation of patients in different stroke stages. Therefore, although the heterogeneity and the low percentage of studies that included cognitive outcomes, seemed that the latter were positively influenced by RT in post-stroke rehabilitation. Future larger RCTs are needed to outline which cognitive scales are most suitable and their cut-off, as well as what cognitive outcome measures to use in the various stages of post-stroke rehabilitation

Acute Delta Hepatitis in Italy spanning three decades (1991–2019): Evidence for the effectiveness of the hepatitis B vaccination campaign

Updated incidence data of acute Delta virus hepatitis (HDV) are lacking worldwide. Our aim was to evaluate incidence of and risk factors for acute HDV in Italy after the introduction of the compulsory vaccination against hepatitis B virus (HBV) in 1991. Data were obtained from the National Surveillance System of acute viral hepatitis (SEIEVA). Independent predictors of HDV were assessed by logistic-regression analysis. The incidence of acute HDV per 1-million population declined from 3.2 cases in 1987 to 0.04 in 2019, parallel to that of acute HBV per 100,000 from 10.0 to 0.39 cases during the same period. The median age of cases increased from 27 years in the decade 1991-1999 to 44 years in the decade 2010-2019 (p < .001). Over the same period, the male/female ratio decreased from 3.8 to 2.1, the proportion of coinfections increased from 55% to 75% (p = .003) and that of HBsAg positive acute hepatitis tested for by IgM anti-HDV linearly decreased from 50.1% to 34.1% (p < .001). People born abroad accounted for 24.6% of cases in 2004-2010 and 32.1% in 2011-2019. In the period 2010-2019, risky sexual behaviour (O.R. 4.2; 95%CI: 1.4-12.8) was the sole independent predictor of acute HDV; conversely intravenous drug use was no longer associated (O.R. 1.25; 95%CI: 0.15-10.22) with this. In conclusion, HBV vaccination was an effective measure to control acute HDV. Intravenous drug use is no longer an efficient mode of HDV spread. Testing for IgM-anti HDV is a grey area requiring alert. Acute HDV in foreigners should be monitored in the years to come