Investigation on the role of microstructure and temperature on tribological characteristics of fine-grained ZE41 Mg alloy

2021 ◽  
pp. 1-8
Author(s):  
M. Venkataiah ◽  
T. Anup Kumar ◽  
K. Venkata Rao ◽  
S. Anand Kumar ◽  
Ravikumar Dumpala ◽  
...  
Keyword(s):  
Mg Alloy ◽  
Tribological Characteristics ◽  
Fine Grained

Tongues of Fire

2018 ◽  
Author(s):  
Nancy Farriss
Keyword(s):  
Cultural Difference ◽  
Language Contact ◽  
Social Contexts ◽  
Culture Contact ◽  
Rhetorical Strategies ◽  
Southern Mexico ◽  
Fine Grained ◽  
Indigenous Church ◽  
Cultural Gaps

Language and translation governed the creation of Mexican Christianity during the first centuries of colonial rule. Spanish missionaries collaborated with indigenous intellectuals to communicate the gospel in dozens of local languages that had previously lacked grammars, dictionaries, or alphabetic script. The major challenge to translators, more serious than the absence of written aids or the great diversity of languages and their phonetic and syntactical complexity, was the vast cultural difference between the two worlds. The lexical gaps that frustrated the search for equivalence in conveying fundamental Christian doctrines derived from cultural gaps that separated European experiences and concepts from those of the Indians. This study focuses on the Otomangue languages of Oaxaca in southern Mexico, especially Zapotec, and relates their role in the Dominican evangelizing program to the larger frame of culture contact in postconquest Mesoamerica. Fine-grained analysis of translated texts is used to reveal the rhetorical strategies of missionary discourse and combines with an examination of language contact in different social contexts. A major aim is to spotlight the role of the native elites in shaping what emerged as a new form of Christianity. As translators, chief catechists, and parish administrators they made evangelization in many respects an indigenous enterprise and the Mexican church it created an indigenous church.

How Artefacts Do Leadership: A Ventriloquial Analysis

2021 ◽  
pp. 089331892199807
Author(s):  
Jonathan Clifton ◽  
Fernando Fachin ◽  
François Cooren
Keyword(s):  
Organizational Communication ◽  
Recent Work ◽  
Distributed Leadership ◽  
Network Theory ◽  
Actor Network Theory ◽  
Fine Grained ◽  
Naturally Occurring ◽  
Human Actors

To date there has been little work that uses fine-grained interactional analyses of the in situ doing of leadership to make visible the role of non-human as well as human actants in this process. Using transcripts of naturally-occurring interaction as data, this study seeks to show how leadership is co-achieved by artefacts as an in-situ accomplishment. To do this we situate this study within recent work on distributed leadership and argue that it is not only distributed across human actors, but also across networks that include both human and non-human actors. Taking a discursive approach to leadership, we draw on Actor Network Theory and adopt a ventriloquial approach to sociomateriality as inspired by the Montreal School of organizational communication. Findings indicate that artefacts “do” leadership when a hybrid presence is made relevant to the interaction and when this presence provides authoritative grounds for influencing others to achieve the group’s goals.

scholarly journals Delta band activity contributes to the identification of command following in disorder of consciousness

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Gonzalo Rivera-Lillo ◽  
Emmanuel A. Stamatakis ◽  
Tristan A. Bekinschtein ◽  
David K. Menon ◽  
Srivas Chennu
Keyword(s):  
Functional Neuroimaging ◽  
Brain Activity ◽  
Disorder Of Consciousness ◽  
Fine Grained ◽  
Electrical Brain Activity ◽  
Delta Band ◽  
Delta Modulation ◽  
Command Following ◽  
Band Activity

AbstractThe overt or covert ability to follow commands in patients with disorders of consciousness is considered a sign of awareness and has recently been defined as cortically mediated behaviour. Despite its clinical relevance, the brain signatures of the perceptual processing supporting command following have been elusive. This multimodal study investigates the temporal spectral pattern of electrical brain activity to identify features that differentiated healthy controls from patients both able and unable to follow commands. We combined evidence from behavioural assessment, functional neuroimaging during mental imagery and high-density electroencephalography collected during auditory prediction, from 21 patients and 10 controls. We used a penalised regression model to identify command following using features from electroencephalography. We identified seven well-defined spatiotemporal signatures in the delta, theta and alpha bands that together contribute to identify DoC subjects with and without the ability to follow command, and further distinguished these groups of patients from controls. A fine-grained analysis of these seven signatures enabled us to determine that increased delta modulation at the frontal sensors was the main feature in command following patients. In contrast, higher frequency theta and alpha modulations differentiated controls from both groups of patients. Our findings highlight a key role of spatiotemporally specific delta modulation in supporting cortically mediated behaviour including the ability to follow command. However, patients able to follow commands nevertheless have marked differences in brain activity in comparison with healthy volunteers.

Job Resources and Strengths Use in Relation to Employee Performance: A Contextualized View

2021 ◽  
pp. 003329412199778
Author(s):  
Luca Tisu ◽  
Andrei Rusu ◽  
Coralia Sulea ◽  
Delia Vîrgă
Keyword(s):  
Employee Performance ◽  
Job Demands ◽  
Job Resources ◽  
Conservation Of Resources ◽  
Role Clarity ◽  
Fine Grained ◽  
Strengths Use ◽  
Individual Strategies ◽  
Moderator Role

Job resources play a prominent role in employee performance literature, yet a fine-grained understanding of how resources are relevant for several performance types is still needed. Relying on the Job Demands-Resources and Conservation of Resources theories, the present study addresses this call in two ways. First, it examines the predictive effect of four job resources (i.e., role clarity, feedback, autonomy, and opportunities for development) on nine types of performance (i.e., proficiency, adaptivity, and proactivity as an individual, team, and organization member). Second, it tests the moderator role of strengths use in these relationships. Data was gathered from a sample of Romanian employees (N = 332) and analyzed via hierarchical multiple linear regression. The results indicate that the selected job resources are, indeed, predictors of different types of employee performance and not in a unitary manner. Role clarity and feedback appear to be the most relevant predictors for various performance types, while autonomy seems to be the least important. Also, strengths use moderates these relationships, but in a reinforcing manner only regarding opportunities for development. The interaction of strengths use with role clarity and feedback renders the latter two obsolete, indicating that individual strategies may act as substitutes for job resources. These findings add to the Job Demands-Resources theory's versatile nature and provide more clarity to practitioners who plan interventions to enhance specific performance types, taking individual strategies into account.

scholarly journals Adopting the Situation in School Questionnaire to Examine Physical Education Teachers’ Motivating and Demotivating Styles Using a Circumplex Approach

2021 ◽  
Vol 18 (14) ◽  
pp. 7342
Author(s):  
Géraldine Escriva-Boulley ◽  
Emma Guillet-Descas ◽  
Nathalie Aelterman ◽  
Maarten Vansteenkiste ◽  
Nele Van Doren ◽  
...  
Keyword(s):  
Physical Education ◽  
Autonomy Support ◽  
Future Research ◽  
Physical Education Teachers ◽  
Structure Control ◽  
Fine Grained ◽  
Circular Structure ◽  
Need Support ◽  
Academic Courses

Grounded in SDT, several studies have highlighted the role of teachers’ motivating and demotivating styles for students’ motivation, learning, and physical activity in physical education (PE). However, most of these studies focused on a restricted number of motivating strategies (e.g., offering choice) or dimensions (e.g., autonomy support). Recently, researchers have developed the Situations-in-School (i.e., SIS-Education) questionnaire, which allows one to gain a more integrative and fine-grained insight into teachers’ engagement in autonomy-support, structure, control, and chaos through a circular structure (i.e., a circumplex). Although teaching in PE resembles teaching in academic courses in many ways, some of the items of the original situation-based questionnaire (e.g., regarding homework) are irrelevant to the PE context. In the present study, we therefore sought to develop a modified, PE-friendly version of this earlier validated SIS-questionnaire—the SIS-PE. Findings in a sample of Belgian (N = 136) and French (N = 259) PE teachers, examined together and as independent samples, showed that the variation in PE teachers’ motivating styles in this adapted version is also best captured by a circumplex structure, with four overarching styles and eight subareas differing in their level of need support and directiveness. The SIS-PE possesses excellent convergent and concurrent validity. With the adaptations being successful, great opportunities for future research on PE teachers (de-)motivating styles are created.

scholarly journals The Role of Frost Processes in the Retreat of River Banks

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1812
Author(s):  
Karol Augustowski ◽  
Józef Kukulak
Keyword(s):  
Relative Role ◽  
Freezing And Thawing ◽  
Fine Grained ◽  
Fluvial Processes ◽  
Precise Calculation ◽  
Erosion Pins ◽  
Summer Half ◽  
Lateral Erosion ◽  
Summer Flood

The rate of bank retreat was measured using erosion pins on the alluvial banks of the rivers in the Podhale region (the boundary zone between Central and Outer Carpathians) during the hydrological year 2013/2014. During the winter half-year (November–April), the bank retreat was mainly caused by processes related to the freezing and thawing of the ground (swelling, creep, downfall). During the summer half-year (May–October), fluvial processes and mass movements such as lateral erosion, washing out, and sliding predominated. The share of fluvial processes in the total annual amount of bank retreat (71 cm on average) was 4 times greater than that of the frost phenomena. Erosion on bank surfaces by frost phenomena during the cold half-year was greatest (up to 38 cm) on the upper parts of banks composed of fine-grained alluvium, while fluvial erosion during the summer half-year (exceeding 80 cm) mostly affected the lower parts of the banks, composed of gravel. The precise calculation of the relative role of frost phenomena in the annual balance of bank erosion was precluded at some stations by the loss of erosion pins in the summer flood.

Evolutions of Microstructure for Multilayered Al-Mg Alloy Composites by Accumulation Roll Bonding (ARB) Process

2011 ◽  
Vol 411 ◽  
pp. 527-531
Author(s):  
Bing Zhang ◽  
Zhong Wei Chen ◽  
Shou Qian Yuan ◽  
Tian Li Zhao
Keyword(s):  
Multilayer Structure ◽  
Optical Microscope ◽  
Alloy Layer ◽  
Mg Alloy ◽  
Micro Hardness ◽  
Roll Bonding ◽  
Fine Grained ◽  
Hardness Tester ◽  
Average Grain Size ◽  
Evolution Of Microstructure

In this paper, accumulative roll bonding (ARB) has been used to prepare the Al/Mg alloy multilayer structure composite materials with 1060Al sheet and MB2 sheet. The evolution of microstructure of the cladding materials during ARB processes was observed by optical microscope, scanning electron microscopy, and micro-hardness was measured by micro-hardness tester. The results show that a multilayer structure material of Al/Mg alloy with excellent bonding characteristics and fine grained microstructure was prepared by ARB processes. With the ARB cycles increasing, Mg alloy layer in multilayer composite material was necked and fractured, and the hardness of the Al and Mg alloy was increased. Average grain size was less than 1μm after ARB4 cycles.

Fine-Grained Structures Associated with Deformation Twin and Its Influence on Tensile Behaviours in a Cold-Rolled Fe-Ni Alloy

2006 ◽  
Vol 503-504 ◽  
pp. 895-900 ◽  
Author(s):  
Tatsuya Morikawa ◽  
Taku Moronaga ◽  
Kenji Higashida
Keyword(s):  
Deformation Twin ◽  
Liquid Nitrogen Temperature ◽  
Invar Alloy ◽  
High Yield ◽  
Fine Grained ◽  
Transmission Electron ◽  
Ni Alloy ◽  
Cold Rolled ◽  
Crystallographic Planes

Fine-grained structures in Fe-36mass%Ni Invar alloy have been investigated by using transmission electron microscopy (TEM). Particular attention has been paid on the role of deformation twinning in the formation of fine-grained structures and its influence on tensile stressstrain behaviours of rolled specimens. In Fe-Ni Invar alloy with a moderate stacking fault energy, deformation twin did not appear in usual cold-rolling at room temperature (RT), where a kind of cell walls was formed and the Cu-type texture was observed. On the other hand, twinning was occurred by rolling when specimens were cooled to liquid nitrogen temperature (LNT) immediately before the rolling. In such case, a fine lamellar structure was developed and the brass-type texture appeared. However, the lamella boundaries did not coincide with any crystallographic planes, and they were intersected with the bands of deformation twin. Specimens rolled by 90% in thickness reduction exhibited tensile stressstrain behaviours similar to those observed in specimens with SPD structures. In particular, specimens rolled at LNT showed high yield strengths and non-uniform deformation.

Improving the Mechanical Properties of AZ31 Mg Alloy by High Ratio Extrusion

2006 ◽  
Vol 503-504 ◽  
pp. 865-870 ◽  
Author(s):  
Yongjun Chen ◽  
Qu Dong Wang ◽  
Jianguo Peng ◽  
Chun Quan Zhai
Keyword(s):  
Mechanical Properties ◽  
High Strength ◽  
High Ratio ◽  
Extrusion Ratio ◽  
Mg Alloy ◽  
Fine Grained ◽  
Az31 Mg Alloy ◽  
Industry Applications ◽  
One Step ◽  
The One

Experiments were conducted both to evaluate the potential for grain refinement, the subsequent mechanical properties at room temperature in samples of AZ31 Mg alloy and also to investigate the relationship between one-step and two-step high ratio extrusion (HRE). The one-step HRE was undertaken using a high extrusion ratio of 70:1 at 250, 300 and 350°C. And the two-step HRE was conducted with an extrusion ratio of 7 for the first step at 250, 300 and 350°C, followed by a second-step extrusion with an extrusion ratio of 10 at 250, 300 and 350°C. The initial grain size in the AZ31 ingot was 100μm and that after one-step HRE became similar to 5μm, after two-step HRE at 250, 300 and 350°C were 2, 4, 7μm, respectively, resulting in superior mechanical properties at ambient temperature. The microstructure of two-step HRE was finer and uniformer than that of one-step HRE and the strength of one-step and two-step HRE were similar, moreover, the elongation of one-step HRE was improved markedly than that of two-step HRE. Dynamic recrystallization and adjacent grain broking during HRE is introduced to explain the effects of one-step and two-step HRE on the microstructure and mechanical properties of AZ31 Mg alloy. The current results imply that the simple HRE method might be a feasible processing method for industry applications, and the multiply steps extrusion are effective to fabricate high strength of fine grained hcp metals.

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