When a crystal deforms plastically, phenomena such as dislocation storage, multiplication, motion, pinning, and nucleation occur over the submicron-to-nanometer scale. Here we report measurements of plastic yielding for single crystals of micrometer-sized dimensions for three different types of metals. We find that within the tests, the overall sample dimensions artificially limit the length scales available for plastic processes. The results show dramatic size effects at surprisingly large sample dimensions. These results emphasize that at the micrometer scale, one must define both the external geometry and internal structure to characterize the strength of a material.
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http://dx.doi.org/10.1126/science.1098993 | DOI Listing |
Curr Med Chem
January 2025
Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia.
Background: Infertility was often considered a female issue, but male infertility emerged significantly after the Covid-19 pandemic. Hence, assessments are crucial for planning policies on health care and family planning and reasons thereof post vaccinations.
Material And Methods: The present study was a case-control, dual-centers, prospective study with normal sperm parameters.
Front Psychol
January 2025
School of Psychology, Fujian Normal University, Fuzhou, Fujian, China.
Introduction: This study aimed to assess the psychometric properties of the Existential Fulfillment Scale (EFS) in a Chinese university student sample, emphasizing the cultural fit of the scale.
Methods: A cohort of 1,600 undergraduate students from six universities in Fujian Province completed questionnaires including the EFS, Meaning of Life Questionnaire (MLQ), Index of Well-Being (IWB), and Self-Depression Scale (SDS). We conducted item analysis, exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and assessments of criterion-related validity, internal consistency, and test-retest reliability.
Appl Psychol Meas
January 2025
Wright State University, Dayton, OH, USA.
This study compared maximum a posteriori (MAP), expected a posteriori (EAP), and Markov Chain Monte Carlo (MCMC) approaches to computing person scores from the Multi-Unidimensional Pairwise Preference Model. The MCMC approach used the No-U-Turn sampling (NUTS). Results suggested the EAP with fully crossed quadrature and the NUTS outperformed the others when there were fewer dimensions.
View Article and Find Full Text PDFBMC Oral Health
January 2025
The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing, 400016, P.R. China.
Objective: To investigate the effects of modified twin-block appliances (MTBA) on obstructive sleep apnea (OSA) and mandibular retrognathia and the changes in the upper airway, hyoid bone position, and hypoxia-related inflammatory marker levels in children with OSA.
Methods: This study included children with OSA and mandibular retrognathia and those with class I without mandibular retrognathia (n = 35 each). The experimental group comprised children with OSA and mandibular retrognathia managed using MTBA.
BMC Med Educ
January 2025
Department of Nursing, Tabriz Islamic Azad University of Medical Sciences, Tabriz, Iran.
Background: An appropriate clinical environment by providing learning opportunities, plays an important role in preparing students to apply the knowledge learned at the bedside. Since the lived experiences of patients in the clinical environment are effective on the quality of student's learning, the present study was conducted with the aim of explaining the lived experiences of patients regarding bedside teaching.
Materials And Methods: The present qualitative study was conducted using a content analysis approach in 2023 at the Imam Sajjad educational and therapeutic center affiliated with Tabriz Islamic Azad University of Medical Sciences.
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