scholarly journals Microgalvanic Corrosion of Mg–Ca and Mg–Al–Ca Alloys in NaCl and Na2SO4 Solutions

Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7140
Author(s):  
Peixu Yang ◽  
Songbo Ye ◽  
Baojing Feng ◽  
Jinhui Liu ◽  
Sensen Huang ◽  
...  
Keyword(s):  
Corrosion Behavior ◽  
Second Phase ◽  
Biomedical Material

As a kind of potential biomedical material, Mg–Ca alloy has attracted much attention. However, the role of Ca-containing intermetallics in microgalvanic corrosion is still controversial. In 0.6 mol/L NaCl and Na2SO4 solutions, the microgalvanic corrosion behavior of the second phase and Mg matrix of Mg–Ca and Mg–Al–Ca alloys was examined. It was confirmed that the Mg2Ca phase acts as a microanode in microgalvanic corrosion in both NaCl and Na2SO4 solutions, with the Mg matrix acting as the cathode and the Al2Ca phase acting as the microcathode to accelerate corrosion of the adjacent Mg matrix. It was also found that Cl− and SO42− have different sensibilities to microgalvanic corrosion.

Computational and Experimental Insights into the Role of Acidic Molecules on the Corrosion Behavior on 7A46 Aluminum Alloy

2021 ◽  
Vol 21 (4) ◽  
pp. 2221-2233
Author(s):  
Yaru Liu ◽  
Qinglin Pan ◽  
Xiangdong Wang ◽  
Ye Ji ◽  
Qicheng Liu ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Aluminum Alloy ◽  
Corrosion Behavior ◽  
First Principles ◽  
First Principles Calculations ◽  
Corrosive Media ◽  
Corrosion Depth ◽  
Corrosion Mechanisms ◽  
Nanoscale Level

The corrosion mechanisms for different corrosive media on the aged 7A46 aluminum alloy were systematically investigated at nanoscale level. The combination of empirical intergranular and exfoliation corrosion behavior was employed, and coupled with first-principles calculations. Results revealed that the dispersed distribution of matrix precipitates (MPs) leads to the enhancement of the corrosion resistance pre-ageing (PA) followed by double-ageing (PA-DA) alloy. The deepest corrosion depth of PA-DA alloy was in hydrochloric acid, and the calculation result demonstrates that the passivation effect in combination with the accumulation of corrosion products in nitric acid protect the PA-DA alloy from further corrosion.

Locally, together and close to the child - how the citizenship of school employees leads to the implementation of global standards of child protection

2021 ◽  
Vol 601 (7) ◽  
pp. 51-67
Author(s):  
Monika Czyżewska
Keyword(s):  
Domestic Violence ◽  
Child Protection ◽  
Interdisciplinary Teams ◽  
Legal Responsibility ◽  
Second Phase ◽  
School Employees ◽  
Social Pedagogy ◽  
Global Standards

For social pedagogy, it is important to answer the question whether the school and its surroundings are today a place where adults, aware of social and legal responsibility, adequately respond to suspicions of domestic violence against schoolchildren, and whether there is a dissemination of child protection standards, which are emphasized in international documents. Using the case study method, in Warsaw's Praga district (which was the Polish "cradle" of interdisciplinary work in the 1990s) I conducted two research (using an interview technique) on the role of schools in preventing child abuse. 10 respondents took part in the first phase of the study in 2009, while in the second phase (in the years 2019–2020) – 15 respondents. The aim of the study (in both phases) was to identify experiences regarding the quality of cooperation among school employees as members of interdisciplinary teams, in two periods of teams’ activity: before the introduction of the amendment to the Act on Counteracting Domestic Violence in 2010, and after its introduction – from 2011 (the aim of the article is to compare these experiences from both periods). The results of the research show that cooperation within the interdisciplinary teams established by the amendment is generally perceived positively by the members of these teams, although those who cooperated before the amendment, i.e., not obligatorily, define today's cooperation as too formalized and bureaucratic. The respondents' statements prove that currently interdisciplinary teams (from the perspective of a school employee in the Praga-Południe district) are less effective, and participation in their work, although obligatory, is relatively less frequent than when the meetings were voluntary.

Cardiac rehabilitation during COVID-19 pandemic – new challenges, new opportunities

2021 ◽  
Vol 14 (3) ◽  
pp. 215-221
Author(s):  
Maciej Janiszewski ◽  
Artur Mamcarz
Keyword(s):  
Secondary Prevention ◽  
Cardiac Rehabilitation ◽  
Second Phase ◽  
Mortality And Morbidity ◽  
Rehabilitation Programs ◽  
Rehabilitation Centers ◽  
New Challenges ◽  
Artery Disease

The role of comprehensive cardiac rehabilitation (CCR) is well established in the secondary prevention of cardiovascular diseases such as coronary artery disease and heart failure. Many clinical trials demonstrated effectiveness of CCR in improving exercise capacity, quality of life, and in reducing cardiovascular mortality and morbidity. However, even before the era of the COVID-19 pandemic comprehensive cardiac rehabilitation program’s implementation, especially the second phase, had many barriers. One of the main reasons for not attending in second phase of CCR was lack of transportation from patient’s home to rehabilitation centers. Additionally, in recent months COVID-19 pandemic has led to closure of many cardiac rehabilitation centres resulting in many eligible patients unable to participate in the optimisation of secondary prevention. During the coronavirus disease-2019 pandemic, hybrid telerehabilitation has become the leading solution in the cardiac rehabilitation programs. The present paper contains key information about structures, effectives and safety of hybrid telerehabilitation during the COVID-19 era.

Effect of Bi Addition on the Corrosion Behavior of Zirconium Alloys

2013 ◽  
Author(s):  
M. Y. Yao ◽  
B. X. Zhou ◽  
Q. Li ◽  
W. P. Zhang ◽  
L. Zhu ◽  
...  
Keyword(s):  
Solid Solution ◽  
Corrosion Resistance ◽  
Corrosion Behavior ◽  
Mass Fraction ◽  
Zirconium Alloys ◽  
Deionized Water ◽  
Second Phase ◽  
Micro Structure ◽  
Second Phase Particles ◽  
Structure Observation

In order to investigate systematically the effect of Bi addition on the corrosion resistance of zirconium alloys, different zirconium-based alloys, including Zr-4 (Zr-1.5Sn-0.2Fe-0.1Cr), S5 (Zr-0.8Sn-0.35Nb-0.4Fe-0.1Cr), T5 (Zr-0.7Sn-1.0Nb-0.3Fe-0.1Cr) and Zr-1Nb, were adopted to prepare the zirconium alloys containing Bi of 0∼0.5% in mass fraction. These alloys were denoted as Zr-4+xBi, S5+xBi, T5+xBi and Zr-1Nb+xBi, respectively. The corrosion behavior of these specimens was investigated by autoclave testing in lithiated water with 0.01 M LiOH or deionized water at 360°C/18.6 MPa and in superheated steam at 400 °C/10.3 MPa. The micro structure of the alloys was examined by TEM and the second phase particles (SPPs) were analyzed by EDS. Micro structure observation shows that the addition of Bi promotes the precipitation of Sn as second phase particles (SPPs) because Sn is in solid solution in α-Zr matrix in Zr-4, S5 and T5 alloys. The concentration of Bi dissolved in α-Zr matrix increase with the increase of Nb in the alloys, and the excess Bi precipitates as Bi-containing SPPs. The corrosion results show that the effect of Bi addition on the corrosion behavior of different zirconium-based alloys is very complicated, depending on their compositions and corrosion conditions. In the case of higher Bi concentration in α-Zr, the zirconium alloys exhibit better corrosion resistance. However, in the case of precipitation of Bi-containing SPPs, the corrosion resistance gets worse. This indicates that the solid solution of Bi in α-Zr matrix can improve the corrosion resistance, while the precipitation of the Bi-containing SPPs is harmful to the corrosion resistance.

scholarly journals Lessons on fruiting body morphogenesis from genomes and transcriptomes of Agaricomycetes

2021 ◽  
Author(s):  
Laszlo G Nagy ◽  
Peter Jan Vonk ◽  
Markus Kunzler ◽  
Csenge Foldi ◽  
Mate Viragh ◽  
...  
Keyword(s):  
Cell Wall ◽  
Fruiting Body ◽  
Expression Patterns ◽  
Schizophyllum Commune ◽  
Gene Families ◽  
Second Phase ◽  
Fruiting Bodies ◽  
Body Development ◽  
Fruiting Body Development

Fruiting bodies of mushroom-forming fungi (Agaricomycetes) are among the most complex structures produced by fungi. Unlike vegetative hyphae, fruiting bodies grow determinately and follow a genetically encoded developmental program that orchestrates tissue differentiation, growth and sexual sporulation. In spite of more than a century of research, our understanding of the molecular details of fruiting body morphogenesis is limited and a general synthesis on the genetics of this complex process is lacking. In this paper, we aim to comprehensively identify conserved genes related to fruiting body morphogenesis and distill novel functional hypotheses for functionally poorly characterized genes. As a result of this analysis, we report 921 conserved developmentally expressed gene families, only a few dozens of which have previously been reported in fruiting body development. Based on literature data, conserved expression patterns and functional annotations, we provide informed hypotheses on the potential role of these gene families in fruiting body development, yielding the most complete description of molecular processes in fruiting body morphogenesis to date. We discuss genes related to the initiation of fruiting, differentiation, growth, cell surface and cell wall, defense, transcriptional regulation as well as signal transduction. Based on these data we derive a general model of fruiting body development, which includes an early, proliferative phase that is mostly concerned with laying out the mushroom body plan (via cell division and differentiation), and a second phase of growth via cell expansion as well as meiotic events and sporulation. Altogether, our discussions cover 1480 genes of Coprinopsis cinerea, and their orthologs in Agaricus bisporus, Cyclocybe aegerita, Armillaria ostoyae, Auriculariopsis ampla, Laccaria bicolor, Lentinula edodes, Lentinus tigrinus, Mycena kentingensis, Phanerochaete chrysosporium, Pleurotus ostreatus, and Schizophyllum commune, providing functional hypotheses for ~10% of genes in the genomes of these species. Although experimental evidence for the role of these genes will need to be established in the future, our data provide a roadmap for guiding functional analyses of fruiting related genes in the Agaricomycetes. We anticipate that the gene compendium presented here, combined with developments in functional genomics approaches will contribute to uncovering the genetic bases of one of the most spectacular multicellular developmental processes in fungi. Key words: functional annotation; comparative genomics; cell wall remodeling; development; fruiting body morphogenesis; mushroom; transcriptome

scholarly journals Teachers’ Perspectives of the use of CLT in ELT Classrooms: A Case of Soran District of Northern Iraq

2017 ◽  
Author(s):  
Arab World English Journal ◽  
Serwan Husein Taha SHERWANI ◽  
Mehmet KILIÇ
Keyword(s):  
Communicative Language Teaching ◽  
Second Phase ◽  
Structured Interviews ◽  
Northern Iraq ◽  
Positive Attitudes ◽  
Teacher Factors ◽  
Efl Teachers ◽  
Teachers Attitudes ◽  
Teachers Perspectives

This mixed-method study aims at exploring Iraqi English as a Foreign Language (EFL) teachers’ attitudes towards Communicative Language Teaching (CLT). The study was conducted in Soran town, in the northern part of Iraq. The participants of the study were 58 EFL teachers from secondary and high school classrooms. In the first phase, a five-point Likert-scale questionnaire was administered (Karavas-Doukas, 1996) to examine the participants’ attitudes towards CLT principles: “place/importance of grammar, group/pair work, quality and quantity of error correction, the role of the teacher in the classroom, the role and contribution of learners in the learning process.” The second phase of the study was qualitative and consisted of semi-structured interviews to examine the reasons behind the implementation of CLT in terms of the factors that hinder and encourage the implementation of CLT in the Iraqi setting. The results of the quantitative analysis revealed that the teachers held overall positive attitudes towards the use of CLT. The findings of the interview phase concluded that the main factors that cause the failure and success of the implementation of CLT in Iraq can be categorized under four headings: educational factors, teacher factors, student factors, and CLT factors. The results of the study suggest that the educational system and the teachers’ communicative competence are essential to promote the employment of CLT in Iraqi EFL classrooms.

scholarly journals Dimensions of social categorization: Inside the role of language

PLoS ONE ◽  
2021 ◽  
Vol 16 (7) ◽  
pp. e0254513
Author(s):  
Anna Lorenzoni ◽  
Mikel Santesteban ◽  
Francesca Peressotti ◽  
Cristina Baus ◽  
Eduardo Navarrete
Keyword(s):  
Social Interactions ◽  
Basque Country ◽  
Social Categorization ◽  
The Other ◽  
Social Implications ◽  
Second Phase ◽  
Community Based ◽  
Daily Exposure ◽  
Bilingual Communities

The present pre-registration aims to investigate the role of language as a dimension of social categorization. Our critical aim is to investigate whether language can be used as a dimension of social categorization even when the languages coexist within the same sociolinguistic group, as is the case in bilingual communities where two languages are used in daily social interactions. We will use the memory confusion paradigm (also known as the Who said what? task). In the first part of the task, i.e. encoding, participants will be presented with a face (i.e. speaker) and will listen to an auditory sentence. Two languages will be used, with half of the faces always associated with one language and the other half with the other language. In the second phase, i.e. recognition, all the faces will be presented on the screen and participants will decide which face uttered which sentence in the encoding phase. Based on previous literature, we expect that participants will be more likely to confuse faces from within the same language category than from the other language category. Participants will be bilingual individuals of two bilingual communities, the Basque Country (Spain) and Veneto (Italy). The two languages of these communities will be used, Spanish and Basque (Study 1), and Italian and Venetian dialect (Study 2). Furthermore, we will explore whether the amount of daily exposure to the two languages modulates the effect of language as a social categorization cue. This research will allow us to test whether bilingual people use language to categorize individuals belonging to the same sociolinguistic community based on the language these individuals are speaking. Our findings may have relevant political and social implications for linguistic policies in bilingual communities.

scholarly journals Restoration of subjectivity: the role of reflection in personality development and humanization of social institutions

2021 ◽  
pp. 1-16
Author(s):  
Vadim Markovich Rozin ◽  
Lyudmila Mikhailovna Karnozova
Keyword(s):  
Restorative Justice ◽  
Personality Development ◽  
Social Institutions ◽  
General Mechanism ◽  
Second Phase ◽  
Resolution Analysis ◽  
Two Phases ◽  
New Perspective ◽  
Personality Process

This article consists of two parts. The firs parts analyzes the general mechanism of reflection within the framework of the theoretical discourse; while the second part the introduced concepts and schemes of reflection are illustrated on the case of “restorative justice”. The analysis of two other cases (“Confession” by St. Augustine, as well as “Confessions” and “Resurrection” by L. Tolstoy) allows characterizing the two phases of psyche – preceding and accompanying reflection. The first phase represents a “crystallization of distortion subjectivity”, and at times its dissolution. The second phase (situation) launches the personality process, which can be described using the terminology of L. S. Vygotstky as “interiorization" of intersubjective; this is the conscious work that gives a new perspective on the situation and its resolution. Analysis is conducted on the two procedures of reflection itself ‒ reflexive way out to the space of “placelesness” (M. Bakhtin) with the shift of integrity and thingness, and reflexive return (G. Shchedrovitsky). Study of the case of restorative justice demonstrates the organizational-technical attitude towards reflection, communication and ensuring mutual understanding between people separated by crime, as a new moment in comparison with the “individual reflection” as internally determined personality process. The inclusion of reflection into social practices and humanities substantiates the possibility of complementing the concept of subjectivity and its “restoration” with the concept of agency as the proclivity for new actions, acquisition of the “authorial position” in relation to one's personal life and interaction with others.

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