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Mn-doped CeO 2 nanoparticles were synthesized using a microwave-assisted hydrothermal method and analyzed through photoluminescence spectroscopy, positron annihilation lifetime spectroscopy (PALS), and electrical resistance measurements, with the aim of determining the effect of Mn incorporation on the electrical properties of ceria. The present study reveals that the initial introduction of Mn results in the proliferation of small defective structures, attributed to the substitution of Ce4+ by Mn2+ and Mn3+. This transformation leads to the increased formation of Ce3+ species, which are linked to the presence of faulty structures associated with oxygen vacancies. The photoluminescence analysis showcases a notable rise in the number of neutral, singly, and doubly ionized oxygen vacancies following the addition of Mn. Concurrently, in pure sample, electrical measurements indicate that Ce3+ species govern the local charge transfer mechanism, facilitated by the formation of Ce 4f1 orbitals. However, the electrons trapped in various oxygen vacancy-related defect states are responsible for the elevation in activation energy observed in Mn-doped CeO 2 samples. Furthermore, electrical measurements exhibit consistent activation energies across all samples when exposed to varying atmospheric conditions. Additionally, the enhanced response in Mn-doped samples is primarily attributed to a significant increase in carrier density. [ABSTRACT FROM AUTHOR]

• Alteration of α-Ag 2 WO 4 defects as a function of temperature. • Photoluminescence spectroscopy as a tool to evaluate oxygen vacancies. • Impedance spectroscopy and PALS as a tool to evaluate complex vacancies. Defects at semiconductors with electron acceptor and donor sites govern the electronic and optoelectronic applications due to their unique electronic properties. This work provides deep insight into the nature of defects and the conduction mechanism in α-Ag 2 WO 4. To this aim, a detailed analysis of the results of XRD with Rietveld refinements, FE-SEM images, and measurements of different spectroscopies (impedance, positron annihilation lifetime, and photoluminescence) are carried out on α-Ag 2 WO 4 samples synthesized by a simple co-precipitation method. Two types of vacancy defects: cationic O-vacancies, and anionic Ag or Ag–O vacancy complexes are elucidated with a Schottky p-type potential barrier. The results indicate that the Ag vacancies remain constant during thermal treatment, while an opposite effect is found for the oxygen vacancies. This behavior governs the multifunctional properties of α-Ag 2 WO 4 semiconductors via a tunneling plus thermionic conduction mechanism. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Breast cancer is the most common malignancy in Brazilian women. In recent years, there has been great progress in and an increasing number of breast-conserving surgical techniques; however, immediate or late morbidity after surgery, in the form of functional impairment and pain, remains a significant clinical problem. Objective: To investigate the relationship between late upper limb functional impairment and the quality of life in women subjected to breast cancer surgery. Method: A total of 81 women participated in the study, with the length of time since surgery ranging from one to five years. A survey of upper limb complaints reported by patients was conducted, and the questionnaires Disabilities of the Arm, Shoulder, and Hand (DASH) and the European Organization for Research and Treatment of Cancer (EORTC QLQC-30 and BR23) were applied. Results: The correlation between the DASH score and the length of time since surgery determined that the longer the time since surgery, the greater the difficulties in functionality of the upper limb (r=0.459; p<0.0001). A statistically significant correlation was observed between the DASH score and health-related quality of life. Conclusion: Late functional impairment had a significant impact on upper limb function in everyday life and health-related quality of life for women who underwent breast cancer surgery. [ABSTRACT FROM AUTHOR]

A CaZrO 3 (CZO) powder was prepared by the soft chemical, polymeric precursor method (PPM). The CZO crystalline structure was investigated by powder X-ray diffraction (XDR), Retvield Refinament data, Raman spectra and ultraviolet–visible absorption spectroscopy. A theoretical study was performed using a periodic quantum mechanical calculation (CRYSTAL09 program). The periodic model built for the crystalline CZO structure was consistent with the experimental data obtained from structural and electronic properties. These results show that the material has an orthorhombic structure with experimental and theoretical gap values of 5.7 eV and 6.2 eV, respectively. In this article, we discuss the hybridization process of the oxygen p-orbitals and of the zirconium d-orbitals and analyze their band structures and density of states (partial and total). [ABSTRACT FROM AUTHOR]

Pre-cooling in water tanks (pre-chiller and chiller) is an important step in preserving the quality of chicken meat. After pre-cooling, the carcasses are hung by the wing and neck for 5 min to allow excess water to drain. The weight of the carcasses is monitored before and after pre-cooling to ensure that weight gain due to water absorption does not exceed 8%. However, no information is available as to how hanging the carcass from other anatomical points might affect water retention of carcasses and water loss during dripping. The present study evaluated the effects of the anatomical point of hanging and hanging time on water retention of carcasses and water loss during dripping. One hundred and sixteen carcasses (mean weight 1,662 ± 13 g) were chilled by cold-water immersion systems in 2 steps (pre-chilling and chilling). The results showed that after chilling, the carcasses needed at least 3 min of dripping time (p < 0.05) to maintain water absorption below 8% of the final weight, and that the point of hanging did not affect water absorption (p > 0.05). Data in this study clearly indicate that leg hanging is a practical alternative, and 5 min of dripping time is needed to maintain water absorption within the desired limit. [ABSTRACT FROM AUTHOR]

• Synthesis of α-Ag 2 W 0.75 Mo 0.25 O 4 using CP method followed by microwave irradiation. • Longest microwave irradiation time enhanced the material properties. • Theoretical results from DFT calculations were compared with experimental data. This article describes the synthesis of α-Ag 2 W 0.75 Mo 0.25 O 4 using a coprecipitation method followed by microwave irradiation for different times. The samples were characterized using X-ray and neutron diffractions with Rietveld refinement, Raman spectroscopy, X-ray fluorescence, and ultraviolet-visible diffused reflectance spectroscopy, as well as by photoluminescence emissions. To complement and rationalize the experimental results, first-principles calculations were performed. The formation and growth of metallic Ag nanoparticles on the surfaces of α-Ag 2 W 0.75 Mo 0.25 O 4 were studied by transmission electron microscopy and energy dispersive X-ray spectroscopy. Results show that α-Ag 2 W 0.75 Mo 0.25 O 4 samples obtained correspond to α-Ag 2 WO 4 /β-Ag 2 MoO 4 heterostructure, and the posterior microwave irradiation favors the process of substituting W by Mo, with subsequent formation of a solid solution. Photocatalytic tests were performed to verify the photocatalytic efficiency against the Rhodamine B. Photoluminescence emissions and photocatalytic results showed that the samples obtained at the longest microwave irradiation time promoted the formation of structural defects and enhanced the material properties. [ABSTRACT FROM AUTHOR]