bluuebunny/crossref_metadata_2025 huggingface dataset:
Low Frontal Alpha Power Is Associated With the Propensity for Burst Suppression: An Electroencephalogram Phenotype for a “Vulnerable Brain”
Authors: Shao Yu Raymond , Kahali Pegah , Houle Timothy T. , Deng Hao , Colvin Christopher , Dickerson Bradford C. , Brown Emery N. , Purdon Patrick L.
Published: May 2020

BACKGROUND:

A number of recent studies have reported an association between intraoperative burst suppression and postoperative delirium. These studies suggest that anesthesia-induced burst suppression may be an indicator of underlying brain vulnerability. A prominent feature of electroencephalogram (EEG) under propofol and sevoflurane anesthesia is the frontal alpha oscillation. This frontal alpha oscillation is known to decline significantly during aging and is generated by prefrontal brain regions that are particularly prone to age-related neurodegeneration. Given that burst suppression and frontal alpha oscillations are both associated with brain vulnerability, we hypothesized that anesthesia-induced frontal alpha power could also be associated with burst suppression.

METHODS:

We analyzed EEG data from a previously reported cohort in which 155 patients received propofol (n = 60) or sevoflurane (n = 95) as the primary anesthetic. We computed the EEG spectrum during stable anesthetic maintenance and identified whether or not burst suppression occurred during the anesthetic. We characterized the relationship between burst suppression and alpha power using logistic regression. We proposed 5 different models consisting of different combinations of potential contributing factors associated with burst suppression: (1) a Base Model consisting of alpha power; (2) an Extended Mechanistic Model consisting of alpha power, age, and drug dosing information; (3) a Clinical Confounding Factors Model consisting of alpha power, hypotension, and other confounds; (4) a Simplified Model consisting only of alpha power and propofol bolus administration; and (5) a Full Model consisting of all of these variables to control for as much confounding as possible.

RESULTS:

All models show a consistent significant association between alpha power and burst suppression while adjusting for different sets of covariates, all with consistent effect size estimates. Using the Simplified Model, we found that for each decibel decrease in alpha power, the odds of experiencing burst suppression increased by 1.33-fold.

CONCLUSIONS:

In this study, we show how a decrease in anesthesia-induced frontal alpha power is associated with an increased propensity for burst suppression, in a manner that captures individualized information above and beyond a patient’s chronological age. Lower frontal alpha band power is strongly associated with higher propensity for burst suppression and, therefore, potentially higher risk of postoperative neurocognitive disorders. We hypothesize that low frontal alpha power and increased propensity for burst suppression together characterize a “vulnerable brain” phenotype under anesthesia that could be mechanistically linked to brain metabolism, cognition, and brain aging.
Emerging Markets at Risk
Authors: Asis Gonzalo , Chari Anusha , Haas Adam
Published: May 2020

Policymakers would like to predict and mitigate the risks associated with the post-global financial crisis rise in corporate leverage in emerging markets. However, long-standing advanced-economy bankruptcy models fail to capture the idiosyncrasies that impact the solvency of emerging market firms. We study how a machine learning technique for variable selection, LASSO, can improve corporate distress risk models in emerging markets. Exploring the trade-off between model fit and predictive power, we find that larger models forecast distress with more accuracy during periods of economic stress (when global factors gain relevance), while more parsimonious specifications outperform during normal times.
Corporate Yields: Effect of Credit Ratings and Sovereign Yields
Authors: Bevilaqua Julia , Hale Galina , Tallman Eric
Published: May 2020

We empirically evaluate the importance of two sources of public information affecting pricing of global corporate bonds: bond ratings provided by rating agencies and sovereign yields of the issuer's country. We find that both in the cross section of firms and over time more variation in corporate bond yields is explained by sovereign yields than by corporate bond ratings. When sovereign yields are high, their importance in pricing corporate bonds declines. In these states, for advanced economies' borrowers, the importance of corporate ratings increases. There is a small upward trend in the importance of corporate ratings over time.
The Financial Center Leverage Cycle: Does It Spread around the World?
Authors: Kaminsky Graciela Laura , Medina Leandro , Wang Shiyi
Published: May 2020

With a novel database, we examine the evolution of capital flows since the collapse of the Bretton Woods system in the early 1970s. We decompose capital flows into global, regional, and idiosyncratic factors. In contrast to previous findings, which mostly use data from the 2000s, we find that booms and busts in capital flows are mainly explained by regional factors and not the global factor. We link leverage in the financial center to regional capital flows and the cost of borrowing in international capital markets to examine the drivers of capital flow bonanzas and busts.
Ownership and Trust in Banks: Evidence from the First Bank in an American Indian Nation
Authors: Feir Donna , Wellhausen Rachel L. , Thrall Calvin
Published: May 2020

In collaboration with an American Indian nation, we conducted a survey that is the first of its kind in Indian Country. The survey explored tribal members' financial experiences in the months before the first bank opened on their reservation. In this article, we connect respondents' reported ex ante trust in banks to their support for the new bank. Descriptively, respondents are highly supportive of the new bank whatever their ex ante trust in banks, but the relationship is nonlinear. Native ownership seems to be particularly silent to those in the middle or low end of the trust distribution.
The Looming Threat of Tariff Hikes: Entry into Exporting under Trade Agreement Renegotiation
Authors: Crowley Meredith A. , Exton Oliver , Han Lu
Published: May 2020

We examine how the looming threat of tariff hikes under a trade agreement renegotiation impacts firm entry into a trading partner's market by exploiting uncertainty over the future UK-EU trade relationship brought about by the June 2016 Brexit referendum. Using the universe of UK export transactions at the firm and product level, we find that uncertainty over future market access to the EU deterred entry modestly in the months immediately after the Brexit vote, but the deterrent effect increased over time.
Time Dependency in Physician Decision-Making
Authors: Jin Lawrence , Tang Rui , Ye Han , Yi Junjian , Zhong Songfa
Published: May 2020

Using data on more than 250,000 emergency department (ED) visits, we study the time-of-day effect on physician decision-making and patient outcomes. After controlling for patient characteristics, physician fixed effects, and work hours, we find that cases treated at night have significantly lower probability of inpatient admission and involve fewer medical tests. These cases are also more likely to revisit the ED, which supports the decline in physician performance. While we cannot completely rule out the possibility of limited hospital arrangements, our findings are most consistent with the detrimental effect of disrupted circadian rhythms during night shifts.
Gender Differences in Scientific Communication and Their Impact on Grant Funding Decisions
Authors: Kolev Julian , Fuentes-Medel Yuly , Murray Fiona
Published: May 2020

Why are women underrepresented in the fields of science, technology, and innovation? Using a sample of Gates and NIH grant applications submitted by a common pool of US-based academic researchers, we implement a range of text analysis methods associated with gendered language. We find that despite significant institutional differences, there are consistent gender differences in scientific communication. By contrast, we find starkly differing impacts of these text characteristics on funding outcomes across our institutional settings. Our findings suggest that institutional reform is likely to be a viable strategy for increasing gender inclusion in science and technology.
A Test of Enhancing Learning in Economics through Nudges
Authors: Balaban Rita , Conway Patrick
Published: May 2020

We test for the importance of nudges in improving student performance in introductory economics courses at UNC-Chapel Hill. We use a randomized controlled trial to test the effectiveness of nudges in encouraging use of academic supports and (jointly) the use of these supports on academic performance. With our aggregated sample the average treatment effects take the correct sign but are uniformly statistically insignificant. This near-zero average effect masks large and significant effects of nudges among subgroups of individuals: females, first years, and individuals of color. Our results identify subgroup-activity pairings for which nudges work at the margin to encourage participation.
Internalizing Externalities: Designing Effective Data Policies
Authors: Hill Ryan , Stein Carolyn , Williams Heidi
Published: May 2020

Many economics journals have recently invested in efforts to archive and curate research data and promote reproducible research. The economics profession has focused relatively less attention on what types of institutions and incentives might encourage and subsidize the creation and sharing of datasets that are likely to encourage novel follow-on research of high social value. This paper describes some examples from other scientific fields of institutions and incentives designed to promote subsequent research and speculates on some potential reforms that could be undertaken within economics to encourage the type of data sharing most likely to encourage socially valuable follow-on research.
Extending the Race between Education and Technology
Authors: Autor David , Goldin Claudia , Katz Lawrence F.
Published: May 2020

The race between education and technology provides a canonical framework that does a remarkable job of explaining US wage structure changes across the twentieth century. The framework involves secular increases in the demand for more-educated workers from skill-biased technological change, combined with variations in the supply of skills from changes in educational access. We expand the analysis backward and forward. The framework helps explain rising skill differentials in the nineteenth and twenty-first centuries but needs to be augmented to illuminate the recent convexification of education returns and implied slowdown in the growth of the relative demand for college workers.
Unpacking Skill Bias: Automation and New Tasks
Authors: Acemoglu Daron , Restrepo Pascual
Published: May 2020

We extend the canonical model of skill-biased technical change by modeling the allocation of tasks to factors and allowing for automation and the creation of new tasks. In our model, factor prices depend on the set of tasks they perform. Automation can reduce real wages and generate sizable changes in inequality associated with small productivity gains. New tasks can increase or reduce inequality depending on whether they are performed by skilled or unskilled workers. Industry-level data suggest that automation significantly contributed to the rising skill premium, while new tasks reduced inequality in the past but have contributed to inequality recently.
The Polarization of Reality
Authors: Alesina Alberto , Miano Armando , Stantcheva Stefanie
Published: May 2020

Americans are polarized not only in their views on policy issues and attitudes toward government and society but also in their perceptions of the same factual reality. We conceptualize how to think about the “polarization of reality” and review recent papers that show that Republicans and Democrats view the same reality through a different lens. Perhaps as a result, they hold different views about policies and what should be done to address economic and social issues. We also show that providing information leads to different reassessments of reality and different responses along the policy support margin, depending on one's political leaning.
Improving Financial Inclusion through Digital Savings and Credit
Authors: Bharadwaj Prashant , Suri Tavneet
Published: May 2020

This paper examines the effects of promotions to increase participation in digital banking and improve financial inclusion. M-Shwari, Kenya's most popular digital banking platform, ran a promotion called Stawisha Na M-Shwari from mid-April 2016 to early June 2016. The promotion incentivized individuals to save and to repay loans. We find large and persistent effects of the promotion on loan-taking behavior. While savings ramp up during the promotional period, we do not see sustained increases in savings after the end of the promotion.
Immigration Enforcement, Deterrence, and Crime
Authors: Orozco-Aleman Sandra , Gonzalez-Lozano Heriberto
Published: May 2020

Does interior enforcement selectively deter Mexican migration? Our study shows that more aggressive enforcement increases the likelihood of having immigrants with US work experience and with jobs secured in the United States before their migration. We also look at whether having employment may be associated with lower crime incidence and shorter detention periods among immigrants. We find that employment decreases the likelihood of observing immigrants committing serious crimes and on the length of immigrant detention. By attracting quality workers, enforcement might decrease crime incidence, along with the length and costs of detention of removable immigrants in the United States.
Can Mentoring Help Female Assistant Professors in Economics? An Evaluation by Randomized Trial
Authors: Ginther Donna K. , Currie Janet M. , Blau Francine D. , Croson Rachel T. A.
Published: May 2020

Women continue to be underrepresented in academic ranks in the economics profession. The Committee on the Status of Women in the Economics Profession of the American Economic Association established the CeMENT mentoring workshop to support women in research careers. The program was designed as a randomized controlled trial. This study evaluates differences between the treatment and control groups in career outcomes. Results indicate that relative to women in the control group, treated women are more likely to stay in academia and more likely to have received tenure in an institution ranked in the top 30 or 50 in economics in the world.
Specifics of Social Stratification in Digital Society
Authors: Grishaeva S.
Published: May 2020

Digital revolution led to severe society modifications, including social structure transformation, primarily due to virtual reality existing simultaneously with reality. Despite that, one of the reasons of this transformation is post-modernism, that includes pluralism as well. As a result, individualized consciousness appears and formation of an increasingly heterogeneous society, the “minority society” begins. On the basis of these minority groups, relatively closed and self-sufficient communities can be created, i.e. neotribalism (according to L. Ionin). The variability of the social environment forms a new character of social inequality, which becomes “fluid”, uncertain, difficult to identify. The article considers new directions for studying social stratification, social inequality and social mobility, as well as issues of identity transformation in a changing society: digitalization makes the social structure dynamic, identity boundaries become fragile and unstable. The results of a sociological study of the social activity of young people on the Internet are described and analyzed. The primary sociological data features certain rationality of young people in evaluating the objectivity of information Internet resources, their ability to determine “discourse, that is, argumentation” in favor of certain forms of using the Internet’s capabilities. It is interesting to note that a significant part of the respondents admits the possibility of information distortion in social networks, but at the same time remains their regular participants. Thus, there is a need for a more serious social diagnosis of the problems of modern digital (network) society.
THE PROBLEM OF IMPLEMENTING DIGITAL TECHNOLOGIES IN THE TRAINING OF MEDICAL ORGANIZATION PERSONNEL
Authors: Tokareva Yuliya , Akulova D. , Lobacheva A.
Published: May 2020

In the conditions of active digital technologies implementation in everywhere, the advantages of their use in various areas of organizations personnel management become obvious. Thus, this article analyzes the possibilities, necessity and effectiveness of using digital technologies for training medical personnel. The article describes the experience of studying employees ' motivation for professional training, their readiness to use remote tools, as well as the choice of a specific software tool that takes into account all the goals and objectives of the training program. The study confirmed the effectiveness of using digital technologies in training medical organizations administrative staff from both a social and economic point of view.
THE STUDY OF THE FEATURES OF THE REGIONAL LABOR MARKET IN THE FORMATION OF THE LABOR MANAGEMENT SYSTEM
Authors: Kaurova O. , Gureeva E. , Mityuhin D. , Gavrilova V.
Published: May 2020

This article is devoted to the problems of management and development of the labor market of the Republic of Buryatia.

This article discusses the concepts of “labor resources”, “labor management system”. The main components of the labor management system in the region are considered. Systematized methods of labor management. The problems of the formation of new approaches to the management of labor resources in the Republic of Buryatia are highlighted. The features of the labor market infrastructure of the Republic of Buryatia are determined. A quantitative and qualitative analysis of the labor resources of the Republic of Buryatia, an analysis of the number of employees by type of economic activity and by form of ownership, an analysis of the distribution of cash incomes of the population of the Republic of Buryatia was carried out.

Based on the analysis, a balance of labor resources was compiled, on the basis of which the main conclusions were made about the state of the labor market of the Republic of Buryatia, specific measures were developed to improve the infrastructure of the labor market of the republic.
Smartwatch study shows promising insight into the future of arrhythmia detection and monitoring
Authors: Palmer Sarah Jane
Published: May 2020

Sarah Jane Palmer discusses the latest research in technology
AUTOAVALIAÇÃO DOS GRADUANDOS DE PEDAGOGIA SOBRE SEU DESEMPENHO ACADÊMICO NO DECORRER DO CURSO
Authors: Cruz Sônia Aparecida Belletti , Silva Ana Flávia Morais da
Published: May 2020

Sob a perspectiva piagetiana, o professor avalia não só o aluno, mas também seus saberes teóricos e práticos. Nos cursos de graduação não pode ser diferente, visto que seus currículos projetam experiências de aprendizagem que visam ao desenvolvimento do pensamento crítico e re?exivo, de capacidades para elaboração teórico-conceitual e resolução de problemas complexos e de competências coerentes às novas exigências do mundo do trabalho. Os resultados da pesquisa, obtidos pela autoavaliação de 22 universitários do curso de Pedagogia, apontam que a maioria considera ter apresentado atitude efetiva de participação e envolvimento nas aulas. Afirmam ter realizado as atividades propostas, colaborando na execução dos trabalhos em grupo, dentre outros comportamentos tidos como adequados e que contribuem para o processo de aquisição de saberes científicos e práticos. Embora haja resistência de muitos professores em adotá-la, a autoavaliação contribui para transformações na esfera pessoal e acadêmica e na preparação para a vida profissional.
EDUCAÇÃO ESCOLAR INDÍGENA: A CULTURA E A HISTÓRIA DO POVO BORARI NA ESCOLA INDÍGENA DE ALTER DO CHÃO.
Authors: SILVA JECILAINE Ferreira , Lopes Rodrigues Gilberto César
Published: May 2020

O tema desta pesquisa é Educação Escolar Indígena. Analisamos a presença da história indígena na escola indígena de Alter do Chão. Onde examinamos a presença da história e cultura dos Borari no currículo escolar. A metodologia envolveu pesquisas exploratória, observação e coletas de dados através de levantamento documental, bibliográfica e de campo durante dois anos. Os resultados indicaram que a maioria dos professores seguem o material didático enviado pelo MEC pois, acham que devem segui-los, por fazer parte do currículo obrigatório, que, segundo eles, dão mais visibilidade a história do sul e sudeste do país e ao Amazonas. Quando aborda o Pará são citados os povos bilíngues. No geral a escola aborda os temas indígenas na semana dos Povos Indígenas no mês de abril, em parceria com acadêmicos indígenas que realizam projetos voltados a valorização desses povos, quando é dado mais abrangência aos Borari.
AS REGRAS DA PRÁTICA PEDAGÓGICA NO CURRÍCULO DE CIÊNCIAS NA EDUCAÇÃO DE JOVENS E ADULTOS:UMA LEITURA BASEADA EM BASIL BERNSTEIN
Authors: Bezerra Débora Silveira Barros , Eugenio Benedito
Published: May 2020

Este artigo tem por objetivo identificar as regras da prática pedagógica presentes no discurso pedagógico e materializado no currículo de Ciências na sala de aula da EJA - Tempo Juvenil. A pesquisa teve como principal referencial teórico os estudos sociológicos de Basil Bernstein (1996), sobre o discurso pedagógico, e os trabalhos desenvolvidos pelo Grupo de Estudos Sociológicos da Sala de Aula (ESSA). Esta investigação é de caráter qualitativo, do tipo estudo de caso. Para o levantamento dos dados, utilizamos os seguintes procedimentos: a observação participante; gravação em áudios das aulas; anotações em diário de campo; questionário socioeconômico e cultural com os alunos e entrevista semiestruturada com o professor. Os resultados apontam para as diversas relações sociológicas que caracterizam as dimensões instrucional e reguladora da prática pedagógica do professor de Ciências no Programa Tempo Juvenil.
MECANISMOS DA GESTÃO DEMOCRÁTICA DA ESCOLA EXPRESSOS NAS NORMAS EDUCACIONAIS BRASILEIRAS
Authors: Vitor Alves Andréia Vicência , Dos Santos Jonata Cristina
Published: May 2020

A gestão democrática é firmada na normatização educacional brasileira como o modelo gestão que deve ser colocada em prática nas instituições educacionais. Tal legislação apresenta como mecanismos dessa gestão a participação, a eleição de diretores, os conselhos escolares e a participação na elaboração do PPP. Assim, o presente estudo tem como intuito apreender como a literatura educacional apresenta essa gestão e seus mecanismos supracitados, a partir de 1988, isso por meio da pesquisa bibliográfica.  Concluímos que a gestão democrática. Tem como mecanismos a participação, a eleição de diretores, os conselhos escolares e a participação na elaboração do PPP, que possibilitam a participação direta e representativa da comunidade escolar; a abertura de espaço para diálogos, debates e discussões no âmbito educacional. Entretanto, o PNE (2014-2024) apresenta a nomeação de diretores associada meritocracia e a critérios de desempenho, que não são considerados características dessa gestão.
A CONCEPÇÃO DE ALFABETIZAÇÃO EM PROGRAMAS FEDERAIS: TENSÕES E (IN)CERTEZAS DA POLÍTICA NACIONAL DE ALFABETIZAÇÃO (2016-2019)
Authors: VIEDES SILVIA CRISTIANE ALFONSO , SOUSA SANDRA NOVAIS , ARANDA MARIA ALICE DE MIRANDA
Published: May 2020

O artigo objetiva analisar as concepções de alfabetização implícitas no Pacto Nacional pela Alfabetização na Idade Certa (Pnaic) e Programa Mais Alfabetização (PMAlfa), que compõem a Política Nacional de Alfabetização, reconfigurada em 2019 no governo Bolsonaro (2019). Para tanto, utilizou-se como procedimentos metodológicos a análise de documentos, tendo como fontes a legislação educacional, os cadernos de programas de formação de alfabetizadores e os documentos que embasam as políticas de avaliação ligadas a esses programas. Como resultados, aponta-se que as mudanças nas políticas de alfabetização ocorridas a partir de 2016 são provenientes de inflexões nas concepções de alfabetização e não exclusivamente dos resultados das avaliações em larga escala. De aprendizagem conceitual de um sistema notacional, no Pnaic, a alfabetização passou a ser considerada a aprendizagem de um código, deslocando-se a ênfase da aprendizagem para o ensino e antecipando para o 1º ano do ensino fundamental o momento de consolidação da alfabetização.Palavras-chave: Alfabetização. Avaliação. Políticas Públicas em Educação. Programa Governamental.
LEGISLAÇÕES MUNICIPAIS SUL-RIO-GRANDENSES E SUAS INTERPRETAÇÕES ACERCA DA GESTÃO DEMOCRÁTICA
Authors: Esquinsani Rosimar Serena Siqueira
Published: May 2020

Referenciar a Gestão Democrática do ensino público é compulsório em legislações educacionais, considerando a previsão do princípio na Constituição Federal de 1988.  Mas, que outros elementos são apresentados em legislações infraconstitucionais, para a visibilidade e materialização de tal princípio?  Como as legislações locais interpretam o princípio?  Portanto, o texto discute registros de gestão democrática do ensino público apresentados em legislações locais, a partir do exame de leis afetas as redes municipais dos 44 municípios sul-rio-grandenses com população acima de 50 mil habitantes.  Abraçando uma metodologia analítico-reconstrutiva, os documentos foram examinados a partir do procedimento da análise de conteúdo, utilizando-se a técnica da análise temática, com destaque para a unidade de significação.  Ao examinar as legislações locais, indica-se a compreensão particular e a prática de mecanismos de gestão democrática.  Como conclusão, os 44 municípios apresentam legislações que regulamentam a gestão democrática em sua rede pública de ensino, materializando mecanismos, espaços e ações para tal modelo de gestão.
MILITARIZAÇÃO DAS ESCOLAS PÚBLICAS NO DISTRITO FEDERAL: PROJETOS DE GESTÃO EM DISPUTA
Authors: Fernandes Silva Edileuza , Silva Maria Abádia da
Published: May 2020

Discute-se a militarização de escolas públicas com ênfase no modelo de gestão compartilhada instituído no Distrito Federal em 2019 em um contexto de acirramento de ideário político conservador, que atenta contra os princípios da gestão democrática previstos na Constituição Federal de 1988, na Lei de Diretrizes e Bases de Educação Nacional e na Lei Distrital nº 4.751 de 2012. Questiona-se em que medida esse modelo de gestão interfere na atuação do diretor para organizar e sistematizar o projeto político-pedagógico da escola. Em termos teórico-metodológicos, fundamenta-se em documentos legais, bibliografia sobre a temática e dados de entrevistas realizadas com gestores eleitos. As reflexões enfatizam que a militarização compõe projeto de imposição da ordem e correção de condutas juvenis pela combinação de dispositivos disciplinares, hierárquicos, correcionais e morais confrontando o projeto democrático de educação e enfraquecendo a atuação do diretor, democraticamente eleito, para fazer a gestão do projeto político-pedagógico da escola.
REFORMA EDUCACIONAL NO SISTEMA ESTADUAL DE ENSINO DE GOIÁS: AS CONTRADIÇÕES DO PROCESSO DE RESPONSABILIZAÇÃO NA GESTÃO DA ESCOLA E NO TRABALHO DO DIRETOR
Authors: SILVA Luís Gustavo Alexandre , Teixeira Ricardo Antonio Gonçalves
Published: May 2020

O artigo pretende analisar questões referentes aos temas reforma educacional e gestão escolar no contexto da rede estadual de ensino de Goiás. A pesquisa origina-se de análise de documentos oficiais da Secretaria de Estado de Educação, Cultura e Esportes de Goiás (Seduce), em especial, os relativos ao documento Pacto pela Educação e ao Programa Reconhecer, bem como ao Sistema de Avaliação Educacional do Estado de Goiás (Saego) e ao Currículo-Referência. A pesquisa se utiliza também de revisão de literatura e de dados do questionário aplicado aos diretores escolares na Prova Brasil 2017 relativos a escolas públicas estaduais do município de Goiânia. Os resultados demonstram a influência dos conceitos de responsabilização e meritocracia nos contornos assumidos pela reforma educacional e sua inflexão sobre a gestão do sistema educativo e o trabalho do diretor escolar no sistema estadual de ensino de Goiás.
ANÁLISE DOS MARCOS LEGAIS DA GESTÃO DEMOCRÁTICA NAS ESCOLAS PÚBLICAS ESTADUAIS DA BAHIA
Authors: Jesus Edna Santos de , Evangelista Mary Adriana dos Santos , Pereira Rodrigo da Silva
Published: May 2020

O presente trabalho objetiva analisar os marcos legais da política de gestão democrática nas escolas públicas estaduais baianas, buscando evidenciar os possíveis avanços e lacunas na legislação vigente e as contradições dessa política com os princípios da Nova Gestão Pública (NGP). Este artigo conclui que é imprescindível o estabelecimento legal de ações permanentes de fortalecimento das instâncias que norteiam e asseguram a política de gestão democrática nas escolas públicas e que  a educação baiana conta com marcos legais considerados avançados para democratização das unidades escolares, mas, contraditoriamente, os princípios e práticas adotadas a partir do referencial político e epistemológico da NGP, acabam por comprometer iniciativas que busquem dar materialidade ao que está subscrito no marco legal.
Transfer function replacement of phenomenological single-mode equations in semiconductor microcavity modeling
Authors: Carcamo M. , Schumacher S. , Binder R.
Published: May 2020

Semiconductor microcavities are frequently studied in the context of semiconductor lasers and in application-oriented fundamental research on topics such as linear and nonlinear polariton systems, polariton lasers, polariton pattern formation, and polaritonic Bose–Einstein condensates. A commonly used approach to describe theoretical properties includes a phenomenological single-mode equation that complements the equation for the nonlinear optical response (interband polarization) of the semiconductor. Here, we show how to replace the single-mode equation by a fully predictive transfer function method that, in contrast to the single-mode equation, accounts for propagation, retardation, and pulse-filtering effects of the incident light field traversing the distributed Bragg reflector (DBR) mirrors, without substantially increasing the numerical complexity of the solution. As examples, we use cavities containing GaAs quantum wells and transition-metal dichalcogenides (TMDs).
Research on a quantitative method for three-dimensional computed tomography of chemiluminescence
Authors: Zhou Gongxi , Li Fei , Wang Kuanliang , Lin Xin , Yu Xilong
Published: May 2020

To develop a more advanced 3D computed tomography of the chemiluminescence method, the first quantitative 3D diagnosis was realized. The nonlinearity coefficient, the nonuniformity coefficient of the camera response, and various optical fiber attenuation coefficients were obtained through correction experiments. The conversion relationship between the number of photons released by the target object per unit time and the camera gray value at a specified solid angle was also calibrated. To verify the quantitative reconstruction equation, 3D reconstructions of a methane–air flat flame and a simulated phantom were performed for comparison. The method can overcome artificial distortions caused by uncorrected reconstruction.
High-power 7.4W TEM00 and wavelength-tunable alexandrite laser with a novel cavity design and efficient fibre-coupled diode-pumping
Authors: Tawy Goronwy , Minassian Ara , Damzen Michael J.
Published: May 2020

We report significant improvement in the performance of TEM00 alexandrite laser operation by employing high power fibre-coupled red diode pumping, novel cavity design, and active direct Shack-Hartmann wavefront sensor measurement of pump-induced lensing. We demonstrate 12.7 W of laser power in low-order (

M
2

∼
5

) mode operation from a compact double-end-pumped cavity, and with novel cavity design, a record power of 7.4 W in TEM00 operation with excellent beam quality (

M
2

≤
1.1

). With single-end pumping, laser power of 4.7 W (

M
2

∼
1.3

) was achieved with slope efficiencies as high as 54.9 %; a record efficiency for red-diode-pumped alexandrite. Using a birefringent filter, continuous laser wavelength tuning from 725-808 nm is achieved in diffraction-limited TEM00 mode, with laser power of 4.7 W at 765 nm, and >1 W across 730-805 nm, which is a higher tunable power than any other directly diode-pumped vibronic laser, to the best of our knowledge.
The silver generation and beauty: Does American culture provide models for positive ageing?
Authors: Fornaciari Federica , Goldman Laine
Published: May 2020

Modern US society’s attitude towards beauty has been shaped by the advertising and cosmetics industry to shun older women and worship youth. The discourse in popular and public culture is that ageing equals failure (). However, the increasing prevalence of emancipatory discourses that are giving a voice to previously silenced minority groups has been making its way to the catwalk with the inclusion of alternative femininity models (), comprising a range of ages, body shapes and ethnic groups, as well as disabled models.

A new cadre of older female models is drawing attention to the issue of ageing that might provide a diversified image of what beauty could look like later in life. Informed by frame theory () and positive ageing (; ), we conducted an exploratory study applying thematic analysis () to media narratives of age and gender in relation to modes of appearance, particularly fashion. In our analysis, we highlighted the catwalk because it is a microcosm of cultural representations. We sought to establish whether the new trend regarding older women on the catwalk is finding expression in the US media, whether it radiates to other fields of public culture, and whether it represents a cultural shift, or a passing trend. We found some evidence for age-friendly catwalk reports, but even those reports reflected, at best, an ambivalent attitude. The results are discussed in the light of a dialectical discourse where inclusivity becomes both an enabling and oppressive attitude at the same time. While wider representation of older, ethnic and disabled women extends the boundaries of inclusivity, it also extends the scope of the normative expectations of beauty standards to older cohorts.
El monstruo bajo la cama: el chavismo como un tema divisorio en América Latina
Authors: Sagarzazu Iñaki , Mouron Fernando
Published: May 2020

Existe una amplia gama de literatura que analiza la interacción entre la política interna y externa. En este sentido, recientemente hemos visto que los políticos estratégicos utilizan líderes extranjeros divisivos como una herramienta para aprovechar en la política interna. Sin embargo, el uso de estos líderes en campañas nacionales, y particularmente las razones por las cuales esto ocurre, no ha recibido mucha atención en la academia. En este artículo, tratamos de abordar este tema identificando cuándo las condiciones están maduras para este uso estratégico de los líderes extranjeros en la política interna. Más específicamente, argumentamos que la imagen de los líderes extranjeros puede usarse cuando presentan las condiciones para convertirse en un problema de cuña. Exploramos esta pregunta mediante el uso de datos de encuestas sobre puntos de vista de Chávez en América Latina junto con indicadores políticos y económicos entre 2005 y 2011. Descubrimos que las percepciones del chavismo son divisivas en países en los que el gobierno en funciones está gobernado por una administración de izquierda. Del mismo modo, mostramos que, en esos países, el chavismo tiene todas las condiciones para convertirse en un problema de cuña, ya que los opositores tienen una percepción homogéneamente negativa de ese movimiento político, mientras que los partidarios del gobierno están divididos en sus puntos de vista sobre el chavismo.
Mechanical feasibility of using red mud as filler in asphalt mixtures to improve permanent deformation
Authors: Lima Mayara Sarisariyama Siverio , Thives Liseane Padilha
Published: May 2020

A lama vermelha é um resíduo sólido resultante do processamento do minério de bauxita para obtenção da alumina (óxido de alumínio – Al2O3), que é o principal composto químico para produzir alumínio. O Brasil possui uma grande reserva de bauxita no estado do Pará e o minério é processado em larga escala. No entanto, no país, a lama vermelha tem sido armazenada inadequadamente no meio ambiente. O Pará está situado no norte do Brasil e apresenta alta temperatura durante todo o ano. O elevado volume de tráfego e as altas temperaturas contribuíram para o surgimento precoce de defeitos nos revestimentos asfálticos dos pavimentos flexíveis. Este estudo laboratorial visa à introdução deste resíduo como fíler em misturas asfálticas densas. Para tanto, foram produzidas misturas de asfalto com 3%, 5% e 7% de lama vermelha (tamanho nominal entre 0,02 a 2.800 micrometros). Como referência, foi produzida uma mistura convencional com 7% de fíler de pó de pedra (tamanho nominal inferior a 0,075 mm). A resistência à deformação permanente das misturas foi avaliada através do simulador de tráfego francês. Como resultado, a mistura com 5% de lama vermelha apresentou o melhor desempenho à deformação permanente e obteve, aos 30.000 ciclos, a porcentagem de afundamento de 3,5%. As misturas asfálticas com lama vermelha apresentaram bom desempenho, com redução da deformação permanente de 12,63 a 42,62% em relação à mistura de referência. A lama vermelha como fíler em misturas asfálticas mostrou ser uma opção viável para reutilizar este resíduo, além de ser uma alternativa ecologicamente adequada.
Fatigue behavior study of a dense graded HMA using the four point bending beam test aided by an in-situ instrumentation at BR-116/RS, Brazil
Authors: Colpo Gracieli Bordin , Brito Lélio Antônio Teixeira , Doering Dionísio , Mocelin Douglas Martins , Hilgert Ana Paula , Johnston Marlova , Ceratti Jorge Augusto Pereira
Published: May 2020

A fadiga é caracterizada pela deterioração estrutural de um material quando submetido a repetidos esforços de tensão-deformação. O ensaio laboratorial comumente empregado no Brasil para análise de fadiga em misturas asfálticas é o ensaio de tração indireta (IDT). Como alternativa ao ensaio IDT, o ensaio de flexão em quatro pontos (4PBBT) submete o material a um estado de tensões mais realístico em relação ao campo. Este trabalho avaliou o comportamento à fadiga de uma mistura asfáltica com ligante modificado por polímero (PG76-11) usando os ensaios IDT e 4PBBT. Um segmento da rodovia BR-116/RS, pavimentado com o mesmo material, foi instrumentado para monitorar as respostas mecânicas na camada asfáltica, permitindo a avaliação do material sob condições de tráfego real, e através do monitoramento ao longo do tempo, permitindo melhor entendimento do desgaste estrutural. Em relação aos ensaios laboratoriais, o ensaio 4PBBT apresentou uma melhor relação com o observado em campo.
Adhesion at asphalt-aggregate interface through surface energy
Authors: Infante Ana Sofia Figueroa , Lizcano Fredy Reyes , Leal Néstor Cely
Published: May 2020

One of the most common problems pavements have is the loss of adhesion and cohesion due to moisture damage.  Tropical countries and rainy seasons are some of the causes for this type of distress on roads.  Another factor that has high influence in this damage is the mineralogy of the aggregate.  This research shows the results of adhesion and cohesion between the aggregates from a limestone quarry and two types of sandstones from different quarries, highly used for roads projects from Colombia, and the asphalt 60-70 (1/10) mm, same PG58-22. For determining the adhesion and cohesion, Bitumen Bond Strength tests were made for dry and wet conditions.  In addition, the Surface Free Energy was measured for the aggregates and the asphalt.  The results indicated that those type of aggregates are highly susceptible to moisture damage, due all values of humidity Index Damage (HDI) were less than 0,5. This indicates that it is necessary to use modifiers for controlling the stripping of the pavements due to Moisture Damage.
SCINDA-GPS derived TEC depletions and amplitude scintillations over Kisumu, Kenya during selected quiet and storm days of 2013 and 2014
Authors: Edward Uluma , Boniface Ndinya , George Omondi
Published: May 2020

Total Electron Content (TEC) depletion and amplitude scintillation (S4) can be derived from, SCINDA-GPS receivers situated in various parts of the equatorial region. In this paper we present results of characterization of TEC depletions and amplitude scintillations over Kisumu, Kenya (Geomagnetic coordinates: 9.64o S, 108.59o E; Geographic coordinates: 0.02o S, 34.6o E) for both selected geomagnetically quiet and geomagnetically disturbed conditions between 1st January 2013 and 31st December 2014 using data derived from the Kisumu NovAtel GSV4004B SCINDA-GPS receiver situated at Maseno University. TEC depletions and amplitude scintillations affect Global Positioning System (GPS) signals in the ionosphere as they propagate from the satellite to the receiver. This study aims to investigate day to day variability of TEC depletions and amplitude scintillations over Kisumu, Kenya during both geomagnetically quiet and geomagnetically disturbed days of 2013 and 2014 which was a high solar activity period for Solar Cycle 24. Seasonal variability of TEC depletions and S4 index is also presented. The Receiver Independent Exchange (RINEX) data for the years 2013 and 2014 was retrieved from the Kisumu SCINDA-GPS receiver, processed to obtain Vertical Total Electron Content (VTEC), S4 and Universal Time (UT) and fed into MATLAB to generate VTEC and S4 plots against UT for each selected quiet and storm day within the 2013 and 2014 period. The obtained results showed a diurnal variation of TEC where TEC was minimum at pre-sunrise, maximum during daytime and minimum during nighttime. The minimum TEC during pre-sunrise and nighttime was attributed to reduced solar intensity while maximum TEC during daytime is attributed to increased solar intensity. Most of the selected quiet and storm days of the years 2013 and 2014 showed TEC depletions and TEC enhancements corresponding with enhanced amplitude scintillations between 1800UT and 20:00UT. This might be attributed to the rapid rise of the F-layer and the increase in the vertical E x B plasma drift due to the Pre-reversal Enhancement (PRE) of the eastward electric field. Post-midnight TEC depletions and amplitude scintillations were observed for some days and this was attributed to the effect of zonal winds which brought post-midnight enhancement of the E x B drift. The percentage occurrence of amplitude scintillations for the selected quiet and storm days exhibited a seasonal dependence with equinoctial months having higher occurrences than the solstitial months. The higher average S4 index during equinoctial months might be attributed to increased solar intensity resulting from the close alignment of the solar terminator and the geomagnetic meridian.Â Â
DETERMINATION OF ADDITIONAL DISPLACEMENT FACTORS OF THE INITIAL CONTOUR OF GEAR WHEELS WITH THE HELP OF BLOCKING CONTOURS
Authors: Timofeev B. P. , Dang N. T.
Published: May 2020

Analyzed the method of calculating the bias coefficients by the method of multicriteria optimization of the engagement (blocking contour) using the KOMPAS-3D program. Analyzed methods for assigning an additional offset of the original contour. The recommendations on the choice of displacement coefficients of spur gears of cylindrical gears in Appendix 2 of GOST 16532–70 are analyzed and additional recommendations are offered to them.
DEVICE FOR HONING PLANES WEDGES VALVES ARTILLERY SYSTEMS
Authors: Bahvalov V. A.
Published: May 2020

The article describes the process of honing the details of command artillery systems, in particular the process of honing planes wedge gate of medium-caliber guns. The article is an analysis of the kinematic scheme of the device and the selected gear ratio device that provides even wear a uniform honing stones and metal removal with a flat machined surface of the work piece due to the commission of the cutting grains honing stones complex movements in the horizontal plane. Next each of the cutting grains will not be repeated for the entire processing cycle. Kinematic diagram of the device with the established and enshrined in the radial grooves of the disc honing stones is implemented in the design and manufacture of devices for honing on vertical milling machines planes wedge gate artillery systems. Investigation of the process of honing the flat specimens made of high-strength gun steels viscous with plan dimensions 130x240 mm possible to determine the rational parameters of flat honing process.Production testing device for honing planes wedge gate of one of the artillery pieces on a vertical milling machine performed at one of the engineering confirmed the efficiency of the device for a flat honing. Honing wedge planes shutter serial products (76 mm caliber gun) on a vertical milling machine using the apparatus discussed in the article improves the processing performance in comparison with conventional processing means 20…35 %. In this case, stability is regulated product design documentation form accuracy and size of the part and the surface roughness of the planes of the wedge gate Ra £ 0,32 microns.
ANALYSIS OF THE USE OF ULTRASONIC TESTING METHODS IN THE FRAMEWORK OF CORROSION MONITORING OF INTERNAL CORROSION AT GAS PRODUCTION FACILITIES IN THE PRESENCE OF CARBON DIOXIDE
Authors: Zapevalov D. N. , Vagapov R. K.
Published: May 2020

The use of various intrusive and non-intrusive methods of corrosion monitoring makes it possible to assess the corrosion situation and the effectiveness of the applied corrosion protection agents in conditions of internal corrosion at gas production facilities due to the presence of aggressive gases. The analysis of the application of ultrasonic testing methods as part of corrosion monitoring of internal corrosion at gas production facilities in the presence of corrosive components is carried out. Ultrasonic thickness measurement is widely used as a non-intrusive method for monitoring internal corrosion and detecting corrosion defects in promising gas fields. Many gas fields (Bovanenkovskoye oil and gas condensate field, Urengoy oil and gas field and others) revealed corrosion defects due to cases of internal corrosion due to the presence of increased amounts of carbon dioxide in the produced hydrocarbons. Under conditions of corrosion in the presence of carbon dioxide, ultrasonic methods for measuring the thickness of a metal have certain limitations associated with the unpredictable local nature of carbon dioxide corrosion, which should be considered when used in gas facilities. The main method for measuring thickness under operational conditions is ultrasonic thickness measurement, which is used in conjunction with radiographic monitoring. Using these two main non-intrusive methods, corrosion monitoring monitors the thinning of the metal, the size and depth of local defects and the dynamics of their change over time. Based on the results of measuring the residual wall thickness of the pipe and equipment, the possibility of their further work is determined, and recommendations are made on extending the safe life of gas facilities. The authors analyzed the literature data on new options and technical solutions for the use of ultrasonic methods in the measurement of the thickness of a metal surface.