Transport mechanisms in structurally ordered piezoelectric CaTaGaSiO (CTGS) single crystals are studied in the temperature range of 1000-1300 °C by application of the isotope O as a tracer and subsequent analysis of diffusion profiles of this isotope using secondary ion mass spectrometry (SIMS). Determined oxygen self-diffusion coefficients enable calculation of oxygen ion contribution to the total conductivity, which is shown to be small. Since very low contributions of the cations have to be expected, the total conductivity must be dominated by electron transport. Ion and electron conductivities are governed by different mechanisms with activation energies (1.9±0.1) eV and (1.2±0.07) eV, respectively. Further, the electromechanical losses are studied as a function of temperature by means of impedance spectroscopy on samples with electrodes and a contactless tone-burst excitation technique. At temperatures above 650 °C the conductivity-related losses are dominant. Finally, the operation of CTGS resonators is demonstrated at cryogenic temperatures and materials piezoelectric strain constants are determined from 4.2 K to room temperature.
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http://dx.doi.org/10.1557/adv.2019.16 | DOI Listing |
Gastric Cancer
January 2025
Department of Medical Oncology, Hospital Clinico Universitario, INCLIVA, Biomedical Research Institute, University of Valencia, Avenida Menendez Pelayo nro 4 accesorio, Valencia, Spain.
Introduction: Gastric cancer (GC) burden is currently evolving with regional differences associated with complex behavioural, environmental, and genetic risk factors. The LEGACy study is a Horizon 2020-funded multi-institutional research project conducted prospectively to provide comprehensive data on the tumour biological characteristics of gastroesophageal cancer from European and LATAM countries.
Material And Methods: Treatment-naïve advanced gastroesophageal adenocarcinoma patients were prospectively recruited in seven European and LATAM countries.
Oncol Ther
January 2025
Coordinator of the International Head and Neck Scientific Group, Padua, Italy.
Introduction: Laryngeal chondrosarcoma (CS) is a rare indolent malignant tumor. High-grade (G3), dedifferentiated (DD), and myxoid (MY) CSs are considered more aggressive subtypes due to their metastatic potential and relatively poor outcomes. The aim of this systematic review is to evaluate treatment modalities and survival outcomes in patients affected by these rarer CS subtypes.
View Article and Find Full Text PDFAm J Sports Med
January 2025
Midwest Orthopaedics at Rush University Medical Center, Chicago, Illinois, USA.
Background: Mismatch between osteochondral allograft (OCA) donor and recipient sex has been shown to negatively affect outcomes. This study accounts for additional donor variables and clinically relevant outcomes.
Purpose: To evaluate whether donor sex, age, donor-recipient sex mismatch, and duration of graft storage affect clinical outcomes and failure rates after knee OCA transplantation.
Am J Sports Med
January 2025
Department of Orthopaedic Surgery, Washington University School of Medicine, St. Louis, Missouri, USA.
Background: Knee injuries resulting in purely cartilaginous defects are rare, and controversy remains regarding the reliability of chondral-only fixation.
Purpose: To systematically review the literature for fixation methods and outcomes after primary fixation of chondral-only defects within the knee.
Study Design: Systematic review; Level of evidence, 5.
Am J Sports Med
January 2025
Section of Young Adult Hip Surgery, Division of Sports Medicine, Department of Orthopedic Surgery, Rush University Medical Center, Chicago, Illinois, USA.
Background: Many studies have examined the prevalence of acetabular version (AV) and femoral version (FV) abnormalities and their effect on patient-reported outcomes (PROs) after hip arthroscopy for femoroacetabular impingement syndrome (FAIS), but few have explored the prevalence and influence of combined version (CV) abnormalities.
Purpose: To (1) describe the distribution of AV, FV, and CV in the largest cohort to date and (2) determine the relationship between AV, FV, and CV and PROs after hip arthroscopy for FAIS.
Study Design: Cohort study; Level of evidence, 3.
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