Topological Superconductor from the Quantum Hall Phase: Effective Field Theory Description

We derive low-energy effective field theories for the quantum anomalous Hall and topological superconducting phases. The quantum Hall phase is realized in terms of free fermions with nonrelativistic dispersion relation, possessing a global $U(1)$ symmetry. We couple this symmetry with a background gauge field and compute the effective action by integrating out the gapped fermions. In spite of the fact that the corresponding Dirac operator governing the dynamics of the original fermions is nonrelativistic, the leading contribution in the effective action is a usual Abelian $U(1)$ Chern-Simons term. The proximity to a conventional superconductor induces a pairing potential in the quantum Hall state, favoring the formation of Cooper pairs. When the pairing is strong enough, it drives the system to a topological superconducting phase, hosting Majorana fermions. Even though the continuum $U(1)$ symmetry is broken down to a $\mathbb{Z}_2$ one, we can forge fictitious $U(1)$ symmetries that enable us to derive the effective action for the topological superconducting phase, also given by a Chern-Simons theory. To eliminate spurious states coming from the artificial symmetry enlargement, we demand that the fields in the effective action are $O(2)$ instead of $U(1)$ gauge fields. In the $O(2)$ case we have to sum over the $\mathbb{Z}_2$ bundles in the partition function, which projects out the states that are not $\mathbb{Z}_2$ invariants. The corresponding edge theory is the $U(1)/\mathbb{Z}_2$ orbifold, which contains Majorana fermions in its operator content.Comment: 40 pages, 5 figures, journal versio

Herbage Production of Tanzania Grass (\u3cem\u3ePanicum maximum\u3c/em\u3e cv. Tanzania) Submitted to Combinations of Frequencies and Intensities of Grazing by Cattle

Animal production from pastures is a complex process comprising three main stages: herbage growth, consumption by grazing animals and conversion into animal products (Hodgson, 1990). Utilisation is the stage where the grazier finds greater flexibility for management, probably because most processes related to harvest of the produced herbage by the grazing animals are very responsive to manipulation and control of defoliation practices. The objective of this study was to evaluate herbage production of a Panicum maximum cv. Tanzania pasture submitted to combinations of frequencies and intensities of grazing

A QUESTÃO DO ATRASO ECONÔMICO LATINO-AMERICANO: UMA ABORDAGEM TEÓRICA PARA A SUA DISCUSSÃO NO ÂMBITO DA ECONOMIA POLÍTICA INTERNACIONAL

Através deste estudo, procuramos apresentar o período entre as independências dos países americanos (final do século XVIII e início do XIX) e a grande depressão mundial de 1929. Com base nos textos e discussões de diferentes autores, defensores de teses distintas, buscamos abordar as causas do atraso relativo das economias dos países latino-americanos e caribenhos em comparação com os Estados Unidos e o Canadá, exemplos de ex-colônias de metrópoles européias que sofreram processos de desenvolvimento diferentes das demais

A importância da experimentação no ensino de Química sobre a ótica dos alunos

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Does the combination of resistance training and stretching increase cardiac overload?

OBJECTIVES: To compare the effects of combinations of resistance training (RT) and static stretching (SS) on heart rate (HR), systolic pressure (SBP), diastolic pressure (DBP), rate pressure product (RPP), oxygen saturation (SpO2), rating of perceived effort (RPE), and heart rate variability (HRV) in men. METHODS: Twelve normotensive healthy men participated in four protocols: a) SS+RT, b) RT+SS, c) RT, and d) SS. Variables were measured before, immediately after, and 15, 30, and 45 min after the sessions. RESULTS: The combination of SS and RT increased (po0.001) HR when compared to the effects of the noncombined protocols (from 2.38 to 11.02%), and this result indicated metabolic compensation. Regarding DBP, there were differences (po0.001) between the RT and SS groups (53.93±8.59 vs. 67.00±7.01 mmHg). SS has been shown to be able to reduce (po0.001) SpO2 (4.67%) due to the occlusion caused by a reduction in the caliber of the blood vessels during SS compared to during rest. The increase in RPP (6.88% between RT and SS+RT) along with the HR results indicated higher metabolic stress than that reflected by the RPE (combined protocols increased RPE from 21.63 to 43.25%). The HRV analysis confirmed these results, showing increases (po0.01) in the LF index between the combined and noncombined protocols. Compared to the effect of RT, the combination of SS and RT promoted a vagal suppression root mean square of the successive differences (RMSSD) index (from 9.51 to 21.52%) between the RT and SS+RT groups (po0.01) and between the RT and RT+SS groups (po0.001). CONCLUSION: Static stretching increases cardiac overload and RPE, reducing oxygen supply, especially when performed in combination with RT

Pregnancy after uterine arterial embolization

OBJECTIVE: To evaluate pregnancy outcomes, complications and neonatal outcomes in women who had previously undergone uterine arterial embolization. METHODS: A retrospective study of 187 patients treated with uterine arterial embolization for symptomatic uterine fibroids between 2005-2008 was performed. Uterine arterial embolization was performed using polyvinyl alcohol particles (500-900 mm in diameter). Pregnancies were identified using screening questionnaires and the study database. RESULTS: There were 15 spontaneous pregnancies. Of these, 12.5% were miscarriages (n = 2), and 87.5% were successful live births (n = 14). The gestation time for the pregnancies with successful live births ranged from 36 to 39.2 weeks. The mean time between embolization and conception was 23.8 months (range, 5-54). One of the pregnancies resulted in twins. The newborn weights (n = 14) ranged from 2.260 to 3.605 kg (mean, 3.072 kg). One (7.1%) was considered to have a low birth weight (2.260 kg). There were two cases of placenta accreta (12.5%, treated with hysterectomy in one case [6.3%]), one case of premature rupture of the membranes (PRM) (6.3%), and one case of preeclampsia (6.3%). All of the patients were delivered via Cesarean section. CONCLUSION: In this study, there was an increased risk of Cesarean delivery. There were no other major obstetric risks, suggesting that pregnancy after uterine arterial embolization is possible without significant morbidity or mortality

Resumen de la Tarea de Análisis de Sentimientos Basado en Aspectos en Portugués (ABSAPT) en IberLEF 2022

Este artículo presenta la Tarea sobre Análisis de Sentimientos basado en Aspectos en Portugués (ABSAPT), realizada en el IberLEF 2022. Les pedimos a los participantes que desarrollaran sistemas capaces de identificar aspectos (AE) y extraer la polaridad (ASC) en textos escritos en portugués. Doce equipos se inscribieron en la tarea, entre los cuales cinco presentaron predicciones e informes técnicos. El sistema con mejor rendimiento logró un valor de precisión (Acc) de 0,67 para la subtarea de AE (Equipo Deep Learning Brasil) y un valor de precisión equilibrada (Bacc) de 0,82 para la subtarea de ASC (Equipo Deep Learning Brasil).This paper presents the task on Aspect-Based Sentiment Analysis in Portuguese (ABSAPT), held within Iberian Languages Evaluation Forum (IberLEF 2022). We asked the participants to develop systems capable of extracting aspects (AE) and classifying sentiment of aspects (ASC) in texts. We created one corpora containing reviews about hotels. Twelve teams registered to the task, among which five submitted predictions and technical reports. The best performing system achieved an Accuracy (Acc) value of 0.67 in AE sub-task (Team Deep Learning Brasil) and a Balanced Accuracy (Bacc) value of 0.82 in ASC sub-task (Team Deep Learning Brasil).This work was financed in part by the following Brazilian research agencies: CAPES and CNPq

Efeitos dos exercícios pilates na função do tronco e na dor de pacientes com lombalgia / Effects of pilates exercices on trunk function and pain in patients with low back pain

Introdução: Evidências científi cas atuais apontam que a falta de resistência da musculatura lombar é o principal fator para desenvolvimento das dores lombares. O exercício físico em geral tem se mostrado benéfi co para recuperação da funcionalidade bem como para melhora dos sintomas clínicos dos pacientes com lombalgia crônica. Objetivo: Avaliar os efeitos de um treinamento físico por meio dos exercícios de Pilates de solo nas variáveis de dor, flexibilidade, equilíbrio, força e resistência dos músculos lombares em pacientes com lombalgia de origem desconhecida. Método: Foram avaliados 12 pacientes com lombalgia crônica (idade média de 33 anos), que realizaram um período de treinamento com o método tradicional de 13 exercícios Pilates (básico e intermediário no mat), duas vezes na semana, com duração de uma hora, durante um total de 11 semanas. As principais medidas de resultados analisadas pré- e pós-treinamento Pilates foram: (1) flexibilidade (Banco de Wells), (2) equilíbrio unipodal (plataforma de força), (3) força lombar (dinamometria), (4) resistência lombar (teste de Sorensen), e dor (Escala Visual Analógica: EVA). Resultados: A amostra fi nal do estudo foi de quatro voluntários devido à perda experimental. Os resultados mostraram uma diminuição significativa da dor (P < 0.05), mas nenhuma diferença significativa entre pré- e pós-treinamento Pilates para as demais variáveis, apesar da leve melhora na fl exibilidade e força. Conclusão: Os resultados do presente estudo apresentaram efeitos benéfi cos do treinamento Pilates para diminuir os sintomas de dor. Entretanto, novos estudos com maior número amostral devem ser realizados para melhor estabelecer os protocolos de exercícios Pilates em pacientes com lombalgia crônica. Introduction: Scientific evidences report that poor back muscle endurance is the most risk factor for developing low back pain. Overall, physical exercise has been effective to recovery of the functioning as well as to improve the clinical symptoms of patients with low back pain. Objective: To assess the effects of Pilates training on mat in variables of flexibility, balance, strength and endurance of the lumbar extensor muscles in patients with low back pain unknown. Method: 16 patients with chronic low back pain (mean age 33 yrs) performed a training program with a mat method of 13 Pilates exercises (basic and intermediate), 2 x a week for a session of approximately 1h, during 11 weeks. The main outcome measures analyzed before (pre-) and post-Pilates training were: fl exibility (sit-and-reach during a Wells test), unipodal support (under a force platform), strength (lumbar dynamometer) and endurance (Sorensen test) of lumbar muscles and pain (VAS). Results: Significant decrease of the pain was found (P < 0.05). However, no significant changes were found for other variables analyzing in pre- and post-training, although the slight improvement in the flexibility and strength. Conclusions: The results of the present study showed the effi cacy of the Pilates exercises to decrease pain. However, more studies would be conducted using much more subjects to establish better standardization of Pilates exercises in patients with low back pain

ALTERNATIVE METHOD TO STUDY SOIL EDAPHIC FAUNA

Os levantamentos realizados sobre popula\ue7\uf5es da fauna ed\ue1fica podem n\ue3o mostrar diferen\ue7as de abund\ue2ncia de organismos por esbarrarem na dificuldade de instala\ue7\ue3o das armadilhas de coleta, rotineiramente utilizadas. Contudo, para uma maior praticidade de implanta\ue7\ue3o e de determina\ue7\ue3o do n\uedvel populacional de organismos ed\ue1ficos, foi avaliada uma metodologia alternativa \ue0 armadilha de Tretzel (modificada), o m\ue9todo Provid, para a coleta da fauna ed\ue1fica, proposto pelos autores deste trabalho. Os dois m\ue9todos foram instalados em nove diferentes \ue1reas, com tr\ueas repeti\ue7\uf5es por m\ue9todo. As \ue1reas diferiram quanto \ue0 localiza\ue7\ue3o, tipo de solo e cobertura vegetal. Os par\ue2metros avaliados para a popula\ue7\ue3o da fauna ed\ue1fica foram riqueza: abund\ue2ncia e \uedndice de diversidade de Simpson. Diferen\ue7as estat\uedsticas significativas n\ue3o foram encontradas para os dois m\ue9todos de coleta de organismos ed\ue1ficos entre as nove \ue1reas analisadas para os par\ue2metros avaliados. Portanto, pode-se concluir que a metodologia de coleta da fauna ed\ue1fica pelo m\ue9todo Provid pode ser utilizada de uma forma t\ue3o eficiente quanto \ue0 armadilha de Tretzel modificada. O m\ue9todo Provid \ue9 pr\ue1tico e f\ue1cil de usar.Study of soil organisms population may not detect differences of organisms number due to the difficulty of pitfall installation methods routinely used. However, to a better practice and determination of population level of soil organisms, it was evaluated an alternative methodology to the pitfall Tretzel (modified). The method is called Provid, for the collection of the soil organisms, proposed by the authors of this work. The two methods were installed in nine different areas, with three replication for each method. The areas differed in terms of location, soil type and vegetable covering. The appraised parameters were richeness, abundance and Simpson\ub4s index. As results, it was not found significant statistical differences for the two methods of collection of organism\ub4s edaphios among the nine analyzed areas, for the appraised parameters. Therefore, that the methodology of collection of the soil organisms for the Provid method can be used as efficient as the pitfall Tretzel modified method. The Provid method is practical and easy to be managed