bluuebunny/crossref_metadata_2025 huggingface dataset:
Letramento Digital e a docência
Authors: Liberato Arruda Hissa Debora
Published: June 2021

Neste texto, refletimos sobre as tradicionais concepções de letramento digital como habilidades e competências necessárias ao uso dos recursos tecnológicos digitais. Com base nos estudos de Jenkins (2006), Martin (2008), Han (2018) e Antunes (2020), problematizamos as concepções no âmbito da docência e suas implicações sociopolíticas para o ensino. Descrevemos e categorizamos as concepções que se fazem presentes em diretrizes curriculares oficiais, como a Base Nacional Comum Curricular (BNCC); em cursos de formação de professores e em eventos nacionais. Elegemos, como corpus de análise 1. o módulo de Cultura Digital do Itinerário Formativo do Centro de Inovação para a Educação Brasileira (CIEB) e suas três unidades – Letramento digital, Ciência e pesquisa na era digital, Cidadania e ética digital; 2. o formulário de autoavaliação de competências digitais de professores, respondido por mais de sessenta mil docentes; e 3. a BNCC. Vimos que o letramento digital pode ser compreendido como técnica de criação de recursos digitais; como aplicação dos recursos na prática docente; como participação responsável e ativa na curadoria de conteúdo digital; e como convergência cultural que integra e engaja os sujeitos na transformação social. Cada uma dessas compreensões impacta diretamente o trabalho docente e em sua prática didática em sala de aula.
Nos bastidores da paisagem
Authors: Sousa Antonio Eusebio de Sousa , Rocha Carlos Eduardo Ribeiro Rocha , Dantas José Carlos Dantas , Reinaldo Thayssllorranny Batista Reinaldo , Oliveira Alexandra Maria de Oliveira , Feliciano Carlos Alberto Feliciano
Published: June 2021

A expansão do capitalismo no campo brasileiro produz contradições que são inerentes à sua existência: ao mesmo tempo que gera riqueza e a concentra para garantir a sua reprodução, expropria e submete sujeitos que se opõem a sua lógica de desenvolvimento, produzindo e acentuando as desigualdades entre as classes sociais. O texto pretende descrever e refletir sobre a violência no campo gerada pelo desenvolvimento do capitalismo, que lacera a paisagem e a relação dos sujeitos com seus territórios, violando direitos individuais e coletivos, ao mesmo tempo que promove inúmeros conflitos territoriais.  O trabalho foi elaborado através da sistematização de diálogos e registros fotográficos nos locais visitados (Cariri cearense, semiárido do Piauí e Cerrado tocantinense em janeiro de 2020), acompanhada de uma leitura crítica dos processos percebidos durante as visitas. Como resultado, identificamos elementos compostos dialeticamente na paisagem e no território e os classificamos em dois grupos: a) as paisagens do conflito territorial (a paisagem percebida concretamente) e as paisagens da resistência territorial do campesinato (a paisagem que materializa as práticas de resistência dos sujeitos).
Avaliação do desempenho socioambiental de propriedade familiar em função da incorporação de práticas agroecológicas no município de Belágua, MA
Authors: Gomes João Flávio Bomfim , Eugênio Vitoriano Lopes Carlos , Costa Veloso José de Ribamar
Published: June 2021

O presente trabalho trata-se de um estudo de caso cujo objetivo é apresentar os resultados da avaliação dos impactos ambientais, sociais e econômicos das melhorias incorporadas ao processo produtivo da mandiocultura, em propriedade familiar rural. A avaliação de impacto foi conduzida no âmbito de projeto da pesquisa cujo objetivo é o de inserir tecnologias e práticas agroecológicas em um sistema de produção de mandioca no município de Belágua, MA. A primeira etapa da avaliação, ou marco zero, procurou identificar as características socioprodutivas dos mandiocultores no município antes da inserção das práticas agrocoecológicas propostas pelo projeto. Para essa etapa foram utilizadas técnicas do DRP. A segunda etapa buscou a avaliar os impactos decorrentes da inserção tecnológica e utilizou como ferramenta de coleta e avaliação de dados o Sistema AMBITEC-AGRO. As práticas agroecológicas inseridas no sistema de produção da mandioca contribuíram diretamente para a redução de técnicas de degradação ambiental, além de apresentar benefícios em itens como segurança no trabalho, a conservação da biodiversidade e dos recursos naturais, emissões à atmosfera, qualidade do solo.
Universidade, reforma agrária e agroecologia
Authors: Rodrigues de Macedo Francielle , Aparecida de Almeida Rosemeire
Published: June 2021

A reforma agrária é a política pública que possibilita ao camponês sem-terra a possibilidade da reprodução social do grupo doméstico por meio da agricultura camponesa. Por sua vez, a agricultura camponesa é aquela que mais se aproxima da agroecologia porque suas práticas de sustentabilidade são inerentes ao modo de vida camponês que possui a terra como “morada da vida”, que é diferente da agricultura capitalista. Nesse sentido, a agroecologia é uma forma de preservação de um modo de vida ligado a uma economia camponesa cuja centro é a recriação da vida do grupo doméstico, não do lucro.  O desafio neste estudo é apreender dinâmicas agroecológicas no assentamento 20 de Março, em Três Lagoas, considerando, especialmente, as dimensões fundamentais da agroecologia, a saber: prática/científica/movimento. Esses caminhos de estudo foram trilhados na busca de articulação da teoria com a empiria na forma de revisão teórica, uso de fontes orais e registros fotográficos. Esta pesquisa encontra sentido na compreensão de que o trabalho acadêmico é uma forma de contribuição para o fortalecimento da luta dos camponeses tanto para o acesso como permanência na terra de vida e trabalho. Entendemos ainda que a ativação do modo de vida camponês é a possibilidade de construção da agricultura camponesa agroecológica, aquela capaz de gerar alimentos sem criar problemas socioambientais. Portanto, devemos ouvir às histórias camponesas de recriação da vida para aprender princípios e caminhos agroecológicos.

 

Palavras-chave: Camponês.  Universidade. Agroecologia. Práxis.
Segregación residencial, segregación escolar y vulnerabilidad por origen nacional
Authors: Lubián Graña Carlos
Published: June 2021

El artículo analiza la relación entre segregación residencial y escolar por origen nacional en Granada. Se analizan los microdatos sobre la población de nacionalidad extranjera residente y escolarizada en la red de centros de primaria para el curso 2014- 2015. Finalmente se exponen, mediante sistemas de información geográfica (GIS), tres estudios de caso de centros de alta concentración teniendo en cuenta los datos de vulnerabilidad en el territorio.

Los resultados del análisis indican, primero, una segregación residencial y escolar alta en el municipio; segundo, que la segregación escolar es mayor que la residencial, lo cual demuestra que ésta última no explicaría el fenómeno en su conjunto; tercero, los estudios de caso analizados indican una propensión a la concentración de determinadas nacionalidades en determinados centros, no explicada por criterios de proximidad.
Using Book Clubs to Support Inquiry in Teacher Education
Authors: Hales Patrick Dean , Hasselquist Laura , Durr Tony
Published: June 2021

The bombardment of information on students in higher education has created a need for not only information processing skills but improved communicative competence and interpersonal relationship skills. In an attempt to address this, we have implemented book clubs in our undergraduate teacher education courses. In these book clubs, we facilitate students in both critique and analysis of perspectives at difference with one another as well as the process of communicating on a professional level. The results have been students who feel more confident in evaluating literature and hosting conversations with critical elements.
Switching from Face-to-Face to Online Instruction Midsemester
Authors: Herold Debora , Chen Tina
Published: June 2021

The COVID-19 pandemic disrupted higher education during Spring 2020 by forcing all face-to-face classes to unexpectedly transition to online learning. To better understand how switching to remote learning affected students and the factors that impacted their ability to successfully complete classes, 168 undergraduate students in three different psychology classes (six sections total) were asked in the last week of the semester about their experiences from before and after the switch. Students reported some decreased access to technology, changes in work responsibilities, some amount of physical illness, and the need to care for others who were physically ill. Notably, students consistently reported increased stress and decreased ability to focus. Students varied in how much they prioritized classes after the switch, which predicted their performance in the class, measured by exam grade, overall grade, and completion of attendance before and after the switch. Importantly, survey respondents significantly differed from non-respondents in their class performance, which suggests that results from voluntary surveys may capture a limited perspective and possibly underestimate the detrimental effects of the shift to online instruction. Implications for planning for future online classes in a global pandemic are discussed.
THE INFLUENCE OF CULTURE ON THE MOTIVATION FOR THE USE OF SOCIAL MEDIA: A COMPARATIVE STUDY OF TURKISH AND GERMAN HIGH SCHOOL STUDENTS
Authors: KIRAN Selçuk , DEMİRÇEVİREN Fatma Göksu
Published: June 2021

This study is an attempt to investigate how cultural contexts determine the use of communication technology by examining the motivations and patterns of using SNS, mainly “Instagram” among teenagers from Turkey and Germany, through a survey. The survey data of total 340 participants were analyzed by using reliability analysis, t-test and Chi-square test. According to the results of the research, Turkish students use social-media with significantly higher motivations of Seeking-Friends and for Entertainment while German students had greater motivation for Seeking-Information. Turkish students have been using Instagram for a longer time and following more accounts in Instagram than German students. While Turkish students use Instagram, LinkedIn and Twitter more, German students use Whatsapp and Tiktok. While Turkish students follow Kim-Kardashian and Kendall-Jenner more, German students follow Cristiano-Ronaldo and Neymar significantly. Turkish students share their posts in Instagram-Stories and use their accounts as private more than expected compared to German students. Turkish students use their real names and spend more time daily in Instagram compared to German students.
Implementation of servant leadership in profit and non-profit context: is it different?
Authors: Amir Diah Astrini , Santoso Claudius Budi , Primadineska Rasistia Wisandianing
Published: June 2021

The purpose of this study is to examine the differences between servant leadership (SL) in the profit and non-profit organization sectors. This study also examines the effectiveness of SL on the subordinate performance in profit and non-profit organizations. A total of 254 subordinates from profit and non-profit organizations participated in this study. This study used non-probability sampling, purposive sampling technique. This study uses MANOVA to examine the differences between SL in profit and non-profit organizations and uses simple regression to examine the effect of SL on employee performance. The results of the study report that there are no significant differences between servant leadership in profit or non-profit organizations. Servant leadership also consistently has a positive and significant effect on subordinate Organizational Citizenship Behavior (OCB) for both profit and non-profit organizations. This research was measured using perceptions of subordinates and using a quantitative approach. The early emergence of SL was associated with religious organizations (non-profit) so that SL was attached to leadership that was more appropriate in non-profit organizations. However, some argue that SL effective in the profit organization sector. This study is expected to provide empirical evidence regarding the application of servant leadership in profit vs non-profit organizations in servant leadership studies.
Evaluation of the Economic Profitability of Using Renewable Energy Sources in Agro-Industrial Companies
Authors: Syromyatnikov Denis , Druzyanova Varvara , Beloglazov Aleksandr , Bakshtanin Alexander , Matveeva Tatiana
Published: June 2021

The study of the impact of the availability of renewable energy sources (RES) on the competitiveness and cost reduction opportunities is an actual objective for agro-industrial enterprises in the present time. The purpose of this paper was to develop a methodological approach based on a questionnaire survey, an integrated indicator of enterprise competitiveness, a model for assessing energy conservation costs, and regression analysis combined with a hierarchical synthesis of 20 Russian agro-industrial companies. The solution of the problem of nonlinear optimization of agro-industrial companies made it possible to determine the excess of the competitiveness criterion over the criterion of energy conservation cost reduction as a result of the use of RES. The conducted regression analysis showed a close relationship between the competitiveness of the companies under study and the availability of RES. Modeling and hierarchical synthesis of the study results confirmed that the use of RES in the activities of agro-industrial companies stimulates their competitive potential reflected by the competitiveness index and minimizes energy conservation costs. It was also found that there is an inverse regression relationship with a high degree of correlation between the provision of RES and the cost of energy-saving measures. Hence, it can be argued that a greater emphasis on the provision of Russian agro-industrial enterprises with RES can lead to their more sustainable and efficient development due to increased competitiveness and better cost reduction strategies.
Household food security and diet quality with chronic energy deficiency among preconception women
Authors: Ramadhani Pradita Putri , Dieny Fillah Fithra , Kurniawati Dewi , Sandi Hartanti , Fitranti Deny Yudi , Rahadiyanti Ayu , Tsani A. Fahmy Arif
Published: June 2021

Background: Chronic energy deficiency (CED) that occurs at risk preconception women during pregnancy increased low birth weight (LBW) in infants. Household food security and diet quality are factors that cause CED. Therefore, this study aims to determine the relationship between household food security and diet quality with CED preconception women.Materials and Methods: We used a cross-sectional study design. The subject of 70 preconception women aged 16-35 years registered in the religious affairs office in Sumowono and Pringapus Subdistrict were selected by consecutive sampling method. Weight and height were measured to assess body mass index to determine CED. Household food security was measured using the Household Food Security Scale Module (HFSSM). Food intake data were obtained using the Semi-Quantitative Food Frequency Questionnaire (SQ-FFQ) and DQI-I (Diet Quality Index-International) to measure diet quality. Bivariate analyses were tested using Rank Spearman and Pearson Product Moment.Results: The prevalence of subjects with CED risk was 48.6% and subjects with  CED was 15.7%. 38.6% of subjects married at the age of 16-20 years, 75.1% of subjects had low household food security and 80% of subjects had low diet quality. There was no significant relationship between household food security and diet quality with CED, namely (p = 0.537) and (p = 0.711). The components of diet quality, namely variation, adequacy, moderation and balance also did not show a significant relationship with CED, respectively with p-value (p = 0.711), (p = 0.523), (p = 0.412), (p = 0.604 )Conclusions: There was no correlation between household food security and CED, also no correlation between diet quality and CED.
Differences in triglyceride levels before and after whey protein intervention in field workers exposed and unexposed to arsenic
Authors: Rahmadhani Eka Putri , Margawati Ani , Kartini Apoina
Published: June 2021

Background: A work environment that is exposed to heavy metals, such as a coal mining environment, can change fat metabolism in the body. Changes in fat metabolism will lead to cardiovascular disease. Consumption of dairy products, e.g. whey protein, can reduce the risk of metabolic disorders and cardiovascular disease.Objectives: To test and analyze the differences in triglyceride levels before and after whey protein intervention to field workers with different working conditions.Materials and Methods: This experimental research with pretest and posttest was conducted on field workers at PT Bukit Asam Tbk. Tarahan Port Unit, Lampung as an Arsenic exposed group and PTPN VII Way Berulu Business Unit as an Arsenic unexposed group. Both groups received 24 grams of whey protein daily for 28 days. The triglyceride levels before and after the intervention were measured by laboratory analysis using the enzymatic calorimetry method. The data were analyzed using independent t-test, Mann Whitney test, and Wilcoxon test.Results: The average triglyceride levels increased by 50.48 ± 98.09 mg/dL in the exposed group and 16.78 ± 67.67 mg/dL in the unexposed group. There was a significant difference in triglyceride levels before and after the whey protein intervention in the two groups.Conclusions: The whey protein intervention increased the triglyceride level in the exposed group and decreased it in the unexposed group.
The effect of addition protein, phosphatidylcholine, phosphatidylserine, and inulin on GFAP levels of acute ischemic stroke patients at Dr. Kariadi Hospital, Semarang
Authors: Wahyuningrum Diah Retno , Retnaningsih Retnaningsih , Kartasurya Martha Irene
Published: June 2021

Background: The occurrence of ischemia causes a loss of energy to switch to anaerobic processes resulting in acidosis due to reduced Adenosina Triphosphate (ATP). This condition makes neuron cells apoptotic. Apoptotic of several biochemical substrates in the brain, such as Glial Fibrillary Acidic Protein (GFAP) exit into the circulatory system which is associated with dysbiosis through immunological pathways.Objectives: To determine the effect of giving enteral formula containing protein, phosphatidylcholine, phosphatidylserine, and inulin on GFAP levels in patients with acute ischemic stroke Dr. Kariadi Hospital.Materials and Methods: This study was done in a single-blind RCT. Eighteen ischemic stroke patients were randomly divided into intervention (9 subjects) and control groups (9 subjects). The intervention group received 69 g of the powdered enteral formula three times a day for seven days. The formula contained protein (15 g), phosphatidylcholine (128 mg),  phosphatidylserine (32 mg), and inulin (3 g). The subject who had diabetes mellitus received for 14 days at a dose of 34.5 g per day (7.5 g protein with additions 64mg phosphatidylcholine, 16mg phosphatidylserine, 1.5 g inulin). The control group received the standard enteral formula from the hospital, which contains (11.8 g protein without additions protein, phosphatidylcholine, phosphatidylserine, and inulin). GFAP levels by ELISA method (Enzyme-linked immunosorbent Assay) at pre and post-intervention.Results: There was a trend of decreasing GFAP levels before and after in the intervention group towards a better direction from 8.37±4.25 to 8.30±4.9 compared with the control group which experienced an increasing trend from 5.4±1.8 to 7.5±4. There was no significant difference in GFAP levels after intervention between groups (p = 0.7).Conclusions: The addition of protein, phosphatidylcholine, phosphatidylserine, and inulin had no significant effect on GFAP levels.
HUBUNGAN PENGETAHUAN DAN PERSEPSI IBU TENTANG STATUS GIZI ANAK DENGAN PERILAKU IBU DALAM PEMBERIAN MAKAN ANAK
Authors: Sari Dyah Purnama , Helmyati Siti , Sari Titi Nurma , Hartriyanti Yayuk
Published: June 2021

Background: One of the factors influencing a child's nutritional status is their mother's or caregivers feeding practice. Mother's behavior in feeding their child is affected by many factors such as social & economic factor, the perception of their child's nutritional status and nutrition knowledge. Objective: To determine the correlation between mothers' knowledge about nutrition and behavior in feeding practice; and the correlation between mothers' perception about their children's nutritional status and behavior in feeding practice (energy, protein, fat, and carbohydrate). Methods: This research was a quantitative study with a cross-sectional design. The samples of this study were 89 pairs of mothers and their child who aged between 1 – 5 years selected by cluster sampling. The subjects of this study took place in HDSS's region, which were Ngaglik and Sleman Districts, Sleman Regency, DI Yogyakarta. This study uses a questionnaire about mothers' perception and knowledge and uses a recall 24-hours to measure the mothers' behavior. The analysis techniques used in this study were Mann Whitney Test and Gamma Test.Results: In general, most mothers have excessive feeding behavior to their child. Mothers with high levels of knowledge tend to have excessive feeding behavior for their child in all nutrients categories. However, mothers with a low level of knowledge tend to have less feeding behavior for energy and fat categories. There are significant correlations between mothers’ knowledge about nutrition with mothers’ feeding practice (p-value <0.001; 0.015; <0.001 and 0.001, respectively). But there is no significant correlation between mothers' perception of their children's nutritional status and mothers' feeding practice for energy, carbohydrate, protein, and fat (p-value 0.854; 0.933; 0.594 and 0.985, respectively). Conclusion: There is a significant correlation between mothers' knowledge about nutrition and mothers' feeding practice. On the other hand, there is no significant correlation between mothers' perception of their children's nutritional status and mothers' feeding practice.
Sistem Tindakan Kepemimpinan Transaksional di Perpustakaan Ganesha Stembayo Yogyakarta
Authors: Wijatiningsih Dwi , Zain Labibah
Published: June 2021

Penelitian ini berfokus pada sistem tindakan pada kepemimpinan transaksional. Tujuan dari penelitian ini adalah untuk melihat sistem tindakan yang ada pada kepemimpinan transaksional di Perpustakaan SMK N 2 Depok Sleman Yogyakarta atau lebih dikenal dengan Perpustakaan Stembayo Yogyakarta. Teori yang digunakan pada penelitian yaitu teori fungsionalisme struktural yang berfokus melahirkan sebuah teori sistem tindakan dengan empat tahapan yaitu; adaptation, goal, integrasi, latensi (AGIL) dan sebuah teori kepemimpinan transaksional dengan empat ciri yaitu; contigen reward, active management by exception, passive management by exception, laissez-faire. Penelitian ini menggunakan metode penelitian kualitatif dengan pendekatan deskriptif, dengan teknik pengambilan data wawancara tidak terstruktur, dan informan penelitian ini adalah Kepala Perpustakaan Ganesha Stembayo. Penelitian ini memiliki hasil temuan strategi agar staff perpustakaan mampu mencapai tujuan dari tugas yang diberikan. Strategi yang dilakukan antara lain memberikan motivasi, selalu mengingatkan untuk bekerja sesuai dengan tupoksi, staff perpustakaan diikutsertakan dalam pelatihan, memberikan reward sesuai prestasi kerja yang dicapai, dan diikut sertakan dalam kompetisi. Kepala Perpustakaan Ganesha Stembayo dalam pencapaian sistem hubungan memiliki strategi agar seluruh tugas yang diberikan kepada staff perpustakaan mencapai tujuan sesuai prosedur, dengan menerapkan plan-do-evaluate-followup (merencanakan-melaksanakan-evaluasi-tindak lanjut). Hasil lainnya menunjukkan bahwa seorang pemimpin dengan gaya transaksional berusaha menjadi mitra kerja ketika seorang staff perpustakaan tidak mampu mencapai tujuannya. Ini dilakukan dengan menunjukkan kesalahan dengan bahasa yang baik dan tidak bernada tinggi agar staff perpustakaan tidak merasa tertekan.
SKEW NORMAL AND SKEW STUDENT-T DISTRIBUTIONS ON GARCH(1,1) MODEL
Authors: Nugroho Didit Budi , Priyono Agus , Susanto Bambang
Published: June 2021

The Generalized AutoRegressive Conditional Heteroskedasticity (GARCH) type models have become important tools in financial application since their ability to estimate the volatility of financial time series data. In the empirical financial literature, the presence of skewness and heavy-tails have impacts on how well the GARCH-type models able to capture the financial market volatility sufficiently. This study estimates the volatility of financial asset returns based on the GARCH(1,1) model assuming Skew Normal and Skew Student-t distributions for the returns errors. The models are applied to daily returns of FTSE100 and IBEX35 stock indices from January 2000 to December 2017. The model parameters are estimated by using the Generalized Reduced Gradient Non-Linear method in Excel’s Solver and also the Adaptive Random Walk Metropolis method implemented in Matlab. The estimation results from fitting the models to real data demonstrate that Excel’s Solver is a promising way for estimating the parameters of the GARCH(1,1) models with non-Normal distribution, indicated by the accuracy of the estimation of Excel’s Solver. The fitting performance of models is evaluated by using log-likelihood ratio test and it indicates that the GARCH(1,1) model with Skew Student-t distribution provides the best fitting, followed by Student-t, Skew-Normal, and Normal distributions.
Model based optimization of a novel ventricular assist device
Authors: Salesch Tobias , Gesenhues Jonas , Habigt Moriz , Mechelinck Mare , Hein Marc , Abel Dirk
Published: June 2021

This paper presents an optimization-based control scheme for a novel left ventricular assist device. This cardiac support system consists of two pumps connected in series and a buffer reservoir in between them. This novel concept for relieving the left ventricle is designed to allow the pre- and afterload on the heart to be explicitly adjusted and independently of each other. The first pump controls the preload of the heart with a known physiological controller. With an iterative model-based optimization, the afterload is minimized by the second pump while complying with all constraints. The proof of the control concept and a comparison to the classical single pump left-sided cardiac support is performed on a hardware-in-the-loop test bench. The results show that with the new left ventricular assist device concept, the afterload can be reduced compared to the classical cardiac support.
Investigating the digital media engagements of very young children at home: Reflecting on methodology and ethics
Authors: Sandberg Helena , Gillen Julia
Published: June 2021

In the media and communications field, research investigating the digital media engagements of very young children at home has largely been restricted to survey methods relying on parental self-reports. Recognizing that qualitative approaches can provide insights in families’ practices, values, and attitudes, we argue for the fruitfulness of an ethnographic perspective, drawing on three cases from the project “A Day in the Digital Lives of children 0–3;” two in Sweden and one in England. Using the concept of methodological responsibility, we argue that methodology and ethics are intrinsically entwined. We offer reflections on dilemmas and challenges involved in our participatory work with children under three and their families, bringing attention to such issues as ensuring initial and ongoing consent, using a video camera in the home and data sharing and dissemination. Building trust in such sensitive work is a complex process but the rewards are considerable.
Harmonic branched coverings and uniformization of CAT(k) spheres
Authors: Breiner Christine , Mese Chikako
Published: June 2021

Let S be a surface with a metric d satisfying an upper curvature bound in the sense of Alexandrov (i.e. via triangle comparison).
We show that an almost conformal harmonic map from a surface into

(
S
,
d
)

{(S,d)}

is a branched covering. As a consequence, if

(
S
,
d
)

{(S,d)}

is homeomorphically equivalent to the 2-sphere

𝕊
2

{\mathbb{S}^{2}}

, then it is conformally equivalent to

𝕊
2

{\mathbb{S}^{2}}

.
Conditions of A-completeness for linear automata over dyadic rationals
Authors: Ronzhin Dmitriy V.
Published: June 2021

We consider the problem of A-completeness in the class of linear automata such that the sets of inputs, outputs and states are Cartesian products of dyadic rationals; systems checked for completeness are comprised of a variable finite set and a fixed additional set. We obtain conditions of A-completeness in terms of maximal subclasses in the cases when the additional set is the set of all unary automata and when the additional set consists of the adder.
Generalized Ricci flow on nilpotent Lie groups
Authors: Paradiso Fabio
Published: June 2021

We define solitons for the generalized Ricci flow on an exact Courant algebroid.
We then define a family of flows for left-invariant Dorfman brackets on an exact Courant algebroid over a simply connected nilpotent Lie group, generalizing the bracket flows for nilpotent Lie brackets in a way that might make this new family of flows useful for the study of generalized geometric flows such as the generalized Ricci flow.
We provide explicit examples of both constructions on the Heisenberg group.
We also discuss solutions to the generalized Ricci flow on the Heisenberg group.
Associated prime ideals of equivariant coinvariant algebras, Steenrod operations, and Krull’s Going Down Theorem
Authors: Smith Larry
Published: June 2021

Let

θ
:

G
↪

GL
⁢

(
n
,
F
)

\theta:G\hookrightarrow\mathrm{GL}(n,\mathbb{F})

be a representation of a finite group 𝐺 over the field 𝔽 and

F
⁢

[
V
]

⊗

F
⁢

[
V
]

G

F

⁢

[
V
]

\mathbb{F}[V]\otimes_{{\mathbb{F}[V]^{G}}}\mathbb{F}[V]

the associated equivariant coinvariant algebra.
The purpose of this manuscript is to determine the associated prime ideals of

F
⁢

[
V
]

⊗

F
⁢

[
V
]

G

F

⁢

[
V
]

\mathbb{F}[V]\otimes_{{\mathbb{F}[V]^{G}}}\mathbb{F}[V]

for representations 𝜃 which are defined over a finite field.
We show that the only possible embedded prime ideal is the maximal ideal completing the delineation of the associated prime ideals of an equivariant coinvariant algebra
for which descriptions of the minimal primes are already in the literature.
In the first part of this manuscript we develop some tools particular to the case where 𝔽 is a Galois field using the Steenrod algebra

P
*

\mathcal{P}^{*}

of a Galois field 𝔽 culminating in a version of W. Krull’s Going Down Theorem for the inclusion

F
⁢

[
V
]

↪

F
⁢

[
V
]

⊗

F
⁢

[
V
]

G

F

⁢

[
V
]

\mathbb{F}[V]\hookrightarrow\mathbb{F}[V]\otimes_{{\mathbb{F}[V]^{G}}}\mathbb{F}[V]

of either of the tensor factors and we then apply this result to determine the height and the coheight of all the

P
*

\mathcal{P}^{*}

-invariant prime ideals in

F
⁢

[
V
]

⊗

F
⁢

[
V
]

G

F

⁢

[
V
]

\mathbb{F}[V]\otimes_{{\mathbb{F}[V]^{G}}}\mathbb{F}[V]

.
Since it has long been known that the associated prime ideals in

F
⁢

[
V
]

⊗

F
⁢

[
V
]

G

F

⁢

[
V
]

\mathbb{F}[V]\otimes_{{\mathbb{F}[V]^{G}}}\mathbb{F}[V]

must be

P
*

\mathcal{P}^{*}

-invariant, our main result is an easy consequence.
As indicated above, our main result is that the associated prime ideals of

F
⁢

[
V
]

⊗

F
⁢

[
V
]

G

F

⁢

[
V
]

\mathbb{F}[V]\otimes_{{\mathbb{F}[V]^{G}}}\mathbb{F}[V]

for 𝔽 a Galois field are either minimal or the maximal ideal, meaning the ideal consisting of all forms of strictly positive degree.
Development of a continuous PET depolymerization process as a basis for a back-to-monomer recycling method
Authors: Biermann Lars , Brepohl Esther , Eichert Carsten , Paschetag Mandy , Watts Marcus , Scholl Stephan
Published: June 2021

This study presents a new approach for the recycling of bilayered PET waste in an efficient, continuous process with a depolymerization degree >97%. The complex PET waste was converted by chemolysis into its monomers ethylene glycol (EG) and the corresponding salt of terephthalic acid (TA) in a twin-screw extruder (TSE). Via this method, the starting materials for PET production were recovered, and highly contaminated PET waste and PET composite materials were transformed into valuable starting materials. The PE layer of the composite PET/PE material remained inert under depolymerization conditions and could be separated by filtration. An increase in the rotational speed by 200 rpm in the TSE reduced the residence time, but the degree of depolymerization was not affected in a proportional manner. Thus, the results indicate that a shorter residence time can be compensated with intensified mechanical agitation due to higher rotational speeds to obtain a similar degree of depolymerization. These results support the potential of this recycling concept to substantially contribute to the implementation of a circular PET economy.
The effect of homogenization on microstructure and hardness of a large-scale high-aluminum Al4.4Co26Cr18Fe18Ni26Ti5.5 Compositionally Complex Alloy cast
Authors: Biermair Florian , Ressel Gerald
Published: June 2021

As any largescale cast material, specific Compositionally Complex Alloys or High Entropy Superalloys contain segregations, leading to unideal, inhomogeneous properties. This work presents the effects of a homogenization heat treatment at 1 150°C for 6 h of a large-scale cast Al4.4Co26Cr18Fe18Ni26Ti5.5 alloy. In order to reveal these effects, homogenized specimens were analyzed and compared to the as-cast state with regard to chemical homogeneity as well as the homogeneity of elemental solution by means of scanning electron microscopy, energy dispersive X-ray spectroscopy as well as X-ray diffraction and hardness measurements. Despite the increased Al content, intermetallic phases and segregations, observable in the as-cast state, dissolve during homogenization. Improved, but not full homogeneity of elemental distribution after annealing can be determined. The improved state of solution and homogeneity agrees with the increasing lattice parameter from 3.572 Å to 3.594 Å and the decreasing hardness from 320.3 HV10 to 245.2 HV10 during homogenization.
COVID-19 infection in children with underlying malignancies in Iran
Authors: Navaeian Amene , Mahmoudi Shima , Pourakbari Babak , Bakhtiari Maryam , Khodabandeh Mahmoud , Abdolsalehi Mohammad Reza , Sharari Alieh Safari , Mamishi Setareh
Published: June 2021

Objectives

Although coronavirus disease 2019 (COVID-19) prognosis is mostly good in pediatric patients with no underlying diseases, there are a few reports on children with oncological underlying malignancies. This study aimed to describe the clinical and laboratory features of 20 children with COVID-19 who had underlying malignancies in an Iranian referral pediatrics hospital.

Methods

All children under 15-year-old of age with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive real-time polymerase chain reaction (PCR) and presence of an underlying malignancy were included in the study.

Results

In this study, among 20 patients, 11 were male (55%). The mean age of the patients was 6.0 ± 4.1 years. Twelve patients (60%) had acute lymphocytic leukemia, two had acute myeloid leukemia (10%), and six had solid organ tumors (30%). The most common symptoms were fever (65%) and cough (65%). We reported severe pneumonia in seven hospitalized patients (35%) and three patients (20%) required intensive care unit admission and mechanical ventilation. Procalcitonin was normal in 73% of the cases (11 out of 15), but it was highly elevated in four cases (27%). Five patients (25%) had positive blood cultures and a mortality of 20% was reported.

Conclusions

This is the largest study on SARS-CoV-2 infected pediatric patients with underlying malignancies in Iran. Since the risk of exposure to SARS-CoV-2 and even death in children with malignancy, either in the hospital or community setting during the pandemic is high, special precautions to reduce the risk of transmission are highly suggested.
On the primary coverings of finite solvable and symmetric groups
Authors: Fumagalli Francesco , Garonzi Martino
Published: June 2021

A primary covering of a finite group 𝐺 is a family of proper subgroups of 𝐺 whose union contains the set of elements of 𝐺 having order a prime power. We denote byσ0⁢(G)\sigma_{0}(G)the smallest size of a primary covering of 𝐺 and call it the primary covering number of 𝐺. We study this number and compare it with its analogueσ⁢(G)\sigma(G), the covering number, for the classes of groups 𝐺 that are solvable and symmetric.
Inverse parabolic problems of determining functions with one spatial-component independence by Carleman estimate
Authors: Imanuvilov Oleg Y. , Kian Yavar , Yamamoto Masahiro
Published: June 2021

For a parabolic equation in the spatial variable

x
=

(

x
1

,
…
,

x
n

)

{x=(x_{1},\ldots,x_{n})}

and time t,
we consider an inverse problem of determining a coefficient which is independent
of one spatial component

x
n

{x_{n}}

by lateral boundary data.
We apply a Carleman estimate to prove a conditional stability estimate for the inverse problem.
Also, we prove similar results for the corresponding inverse source problem.
Fixed angle inverse scattering in the presence of a Riemannian metric
Authors: Ma Shiqi , Salo Mikko
Published: June 2021

We consider a fixed angle inverse scattering problem in the presence of a known Riemannian metric. First, assuming a no caustics condition, we study the direct problem by utilizing the progressing wave expansion. Under a symmetry assumption on the metric, we obtain uniqueness and stability results in the inverse scattering problem for a potential with data generated by two incident waves from opposite directions. Further, similar results are given using one measurement provided the potential also satisfies a symmetry assumption. This work extends the results of
[Rakesh and M. Salo,
Fixed angle inverse scattering for almost symmetric or controlled perturbations,
SIAM J. Math. Anal. 52 2020, 6, 5467–5499]
and
[Rakesh and M. Salo,
The fixed angle scattering problem and wave equation inverse problems with two measurements,
Inverse Problems 36 2020, 3, Article ID 035005]
from the Euclidean case to certain Riemannian metrics.
Understanding thermal and rheological behaviors of bimodal polymethyl methacrylate (BPMMA) fabricated via solution blending
Authors: Yu Yangnan , Yang Bin , Pan Yang , Jia Ning , Wang Shun , Yang Yingdong , Zheng Zhengzhi , Su Lifen , Miao Jibin , Qian Jiasheng , Xia Ru , Shi You
Published: June 2021

In this work, a series of bimodal polymethyl methacrylate (BPMMA) was fabricated via solution-blending two neat PMMA resins. Rheology, DMTA, thermal infrared imager measurements were used in an attempt to probe the internal structure of the as-prepared BPMMA. It was demonstrated that the thermorheological behavior of the BPMMA was heavily dependent on shear rate, temperature as well as blending ratio. In addition, a typical “V-shaped” response, namely, a dip in storage modulus (G′) followed by an upturn in the plot of G′ versus measuring temperature for D4 (with lower weight-average molecular weight) was observed, characteristic of occurrence of thermorheological complexity. Our experimental results of physical–mechanical testings suggested that the BPMMA had better comprehensive properties than those of their neat PMMA counterparts.
Thermodynamics of the micellization of quaternary based cationic surfactants in triethanolamine-water media: a conductometry study
Authors: Osundiya Medinat O. , Olaseni Segun E. , Olowu Rasaq A. , Owoyomi Olanrewaju
Published: June 2021

The effect of triethanolamine, a solvent with wide technical and industrial benefit on the micellization of an aqueous mixture of cationic surfactants, dodecyltrimethylammonium bromide (DETAB) and hexadecyltrimethylammonium bromide (HATAB) was studied to examining the stability of the mixed micelles at 298.1, 303.1, 308.1 and 313.1 K using the electrical conductance method. The values of the critical micelle concentration (C*) were found to decrease with an increase in the concentration of triethanolamine (TEA). The values of the free energy of micellization (ΔGm) were negative at a particular temperature, and the extent of spontaneity was discovered to increase when the concentration of TEA was increased. However, an increase in temperature was observed to have a negative linear relationship with the spontaneity of the process. The formation of the mixed micelles was an exothermic process, and it was also TEA and temperature-dependent with a trend similar to those observed in the free energy of micellization (ΔGm). The degree of disorderliness of the system was also found to be entropy driven at a higher concentration of TEA. The synergistic interaction between the molecules of DETAB–HATAB in the presence of TEA (0.4% v/v) and the spontaneity of the system was at the maximum at 0.1:0.9 mol fraction ratio and the energetics of the system was discussed based on hydrophobic–solvophobic interaction of the monomers in TEA at elevated temperatures.
Healing Traditions in Coptic Magical Texts
Authors: Dosoo Korshi
Published: June 2021

Within the ‘market of healing’ of Christian Egypt (here broadly considered as the fourth through twelfth centuries CE), ‘magical’ practitioners represent an elusive yet recurrent category. This article explores the evidence for magical healing from three perspectives – first, literary texts which situate ‘magicians’ in competition with medical and ecclesiastical healing; second, the papyrological evidence of Coptic-language magical texts, which provide evidence for concepts of disease, wellness, and their mediation; and finally confronting the question of how these healing traditions might be understood within the methodologically materialistic framework of academic history, using the concepts of placebo and healing as a performance.
The Question of the Effectiveness of Coptic Pharmacological Prescriptions
Authors: Grons Anne
Published: June 2021

Coptic pharmacological texts offer a multitude of medical prescriptions concerning various afflictions, such as eye or skin irritations, affections of the viscera, or even psychological complaints. The content of these texts is medical, and in most cases bereft of any magical or religious ideas. They usually compile prescriptions according to symptoms and/or afflictions, without any further organising principle. Only a handful of texts are grouped according to the illness or to the medicinal plants used. Almost every prescription follows a pattern, with four formal elements: 1) the medical indication (or purpose), 2) the (basic) ingredients, 3) the procedure and application, and 4) the effects and/or the effectiveness of a remedy, or further information. In this article, I give an overview of the entire corpus of Coptic medical prescriptions, explore the four main elements, and especially the discussions of efficacy. I also examine the material in light of placebo research, to see whether something like a placebo effect may have influenced how the pharmacological texts were formulated.
Quel corpus pour l’étude du dialecte niçois ?
Authors: Del Giudice Philippe
Published: June 2021

A new project has just been launched to write a synchronic, descriptive grammar of Niçois, the Occitan dialect of Nice. In this article, I define the corpus of the research. To do so, I first review written production from the Middle Ages to the present. I then analyze the linguistic features of Niçois over time, in order to determine the precise starting point of the current language state. But because of reinforced normativism and the decreasing social use of Niçois among the educated population, written language after WWII became artificial and does not really correspond to recordings made in the field. The corpus will thus be composed of writings from the 1820’s to WWII and recordings from the last few decades.
Modelos para estimar volumen fustal y ahusamiento para Manilkara zapota (L.) P. Royen en Quintana Roo, México
Authors: Hernández Ramos Jonathan , García-Cuevas Xavier , Hernández-Ramos Adrián , Tamarit-Urias Juan Carlos , Buendía-Rodríguez Enrique
Published: June 2021

Manilkara zapota es una especie forestal abundante y con importancia comercial maderable. Estimar el volumen y proyectar la distribución de productos maderables para realizar un inventario preciso contribuye al manejo de la especie. El objetivo fue ajustar modelos de volumen fustal (Vf) y ahusamiento (d) para árboles de M. zapota que crecen en los bosques tropicales del centro y sur del estado de Quintana Roo, México. Se usó un total de 186 árboles para ajustar 10 modelos mediante máxima verosimilitud: ocho para Vf y dos en d. Utilizando los valores en los estadísticos del coeficiente de determinación, raíz del error cuadrático medio (RMSE) y valores de verosimilitud, los modelos de Schumacher-Hall y Cielito 3 fueron seleccionados para estimar el Vf y d, respectivamente. Se explicó más del 93% de la muestra empleada con una desviación global menor del 6.5%, donde el factor de forma promedio fue de 0.5.
Watching Movies Unfold, a Frame-by-Frame Analysis of the Associated Neural Dynamics
Authors: Monk Anna M. , Barry Daniel N. , Litvak Vladimir , Barnes Gareth R. , Maguire Eleanor A.
Published: June 2021

Our lives unfold as sequences of events. We experience these events as seamless, although they are composed of individual images captured in between the interruptions imposed by eye blinks and saccades. Events typically involve visual imagery from the real world (scenes), and the hippocampus is frequently engaged in this context. It is unclear, however, whether the hippocampus would be similarly responsive to unfolding events that involve abstract imagery. Addressing this issue could provide insights into the nature of its contribution to event processing, with relevance for theories of hippocampal function. Consequently, during magnetoencephalography (MEG), we had female and male humans watch highly matched unfolding movie events composed of either scene image frames that reflected the real world, or frames depicting abstract patterns. We examined the evoked neuronal responses to each image frame along the time course of the movie events. Only one difference between the two conditions was evident, and that was during the viewing of the first image frame of events, detectable across frontotemporal sensors. Further probing of this difference using source reconstruction revealed greater engagement of a set of brain regions across parietal, frontal, premotor, and cerebellar cortices, with the largest change in broadband (1–30 Hz) power in the hippocampus during scene-based movie events. Hippocampal engagement during the first image frame of scene-based events could reflect its role in registering a recognizable context perhaps based on templates or schemas. The hippocampus, therefore, may help to set the scene for events very early on.