Four quaternary Zintl phases with mixed-cations in the YbCaAlSb (4.81 ≤ x ≤ 10.57) series have been synthesized by using the arc-melting and the Sn metal-flux reaction methods, and the isotypic crystal structures of the title compounds have been characterized by both powder and single-crystal X-ray diffraction (PXRD and SXRD) analyses. The overall crystal structure adopting the CaAlSb-type can be described as a pack of four different types of the spiral-shaped one-dimensional octahedra chains with various turning radii, each of which is formed by the distorted ((Yb/Ca)Sb₆) octahedra. Four symmetrically-independent cationic sites contain mixed occupations of Yb and Ca with different mixing ratios and display a particular site preference by two cationic elements. Two hypothetical structural models of Yb₄CaAlSb with different cationic arrangements were designed and exploited to study the details of site and bond energies. QVAL values provided the rationale for the observed site preference based on the electronegativity of each atom. Density of states (DOS) curves indicated a semiconducting property of the title compounds, and crystal orbital Hamilton population (COHP) plots explained individual chemical bonding between components. Thermal conductivity measurement was performed for YbCaAlSb, and the result was compared to compounds without mixed cations.
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http://dx.doi.org/10.3390/ma9070553 | DOI Listing |
Prostate
January 2025
VUI Center for Outcomes Research, Analysis, and Evaluation, Henry Ford Health System, Detroit, Michigan, USA.
Introduction: PSA screening remains a pivotal tool for early prostate cancer (PCa) detection. International guidelines rely on evidence from three major randomized clinical trials: ERSPC, PLCO, and CAP. We aim to examine the percentage of patients in real-world practice who get PSA screening as defined by each of the aforementioned trials.
View Article and Find Full Text PDFLangenbecks Arch Surg
January 2025
Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, 138, Sheng-Li Road, Tainan, 70428, Taiwan.
Background: As survival following PD improved, long-term complications have emerged as an issue in current era. Pancreaticojejunostomy stenosis is the common long-term sequel after PD but rarely addressed. This study aimed to investigate the benefit of pancreatic duct stent in reducing PJ stenosis after PD.
View Article and Find Full Text PDFClinics (Sao Paulo)
January 2025
Department of Clinical Medicine, Faculdade de Medicina, Universidade de São Paulo (FMUSP), São Paulo, SP, Brazil.
Introduction: The OSCE has been a robust tool for assessing clinical skills in medical education, adaptable across various clinical domains and stages. The COVID-19 pandemic, however, posed significant challenges to traditional assessment methods. This led to the development of the OSVE as an alternative.
View Article and Find Full Text PDFJ Voice
January 2025
Department of Speech and Language Therapy, School of Health Rehabilitation Sciences, University of Patras, Patras, Greece; A' ENT University Clinic, Medical School, National Kapodistreian University of Athens, Athens, Greece. Electronic address:
Objectives: The Singing Voice Handicap Index (SVHI) was culturally adapted and validated in Greek to examine the impacts of voice problems on a singer's everyday life.
Methods: The translated version was administered to 120 singers in total, along with the translated version of the Voice Handicap Index (VHI), a sort voice history questionnaire, two Self-Rating Dysphonia Severity Scales (SRDSSs), and two visual analog scales. A week after the original completion of the Greek version of SVHI, a second copy of the SVHI was administered to 50% of the participants.
Ann Allergy Asthma Immunol
January 2025
Center for Drug Safety and Immunology, Vanderbilt University Medical Centre, Nashville, Tennessee, USA; Institute for Immunology and Infectious Diseases, Murdoch University, Murdoch, Western Australia, Australia.
Background: Donor acquired allergy (DAA) occurs when donors transfer their allergies to recipients through solid organ transplant (SOT). However, the risk of DAA in recipients of organs from allergic donors has not been systematically characterized.
Objective: We sought to synthesize the available evidence on the risk of DAA in SOT recipients.
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