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An experimental study for fabrication, physical, FTIR spectroscopy, ultrasonic waves, and mechanical properties of quaternary B2O3–Bi2O3–NaF–ZrO2 glasses was introduced. The fabricated glasses have the chemical formula 65B2O3–25NaF–(10-x)Bi2O3–xZrO2; x = 0 (Zr0), 2 (Zr2), 4 (Zr4), 5 (Zr5), and 6 (Zr6) mol% and produced via the melt quenching process. The longitudinal VL and shear VS velocities were measured using ultrasonic flaw detector. FTIR spectra were recorded in the wavenumber range 400–1550 cm−1. The density of the fabricated glasses reduces linearly from 3400 ± 6 (kg/m3) for Zr0 sample with free ZrO2 to 3099 ± 4 (kg/m3) for Zr6 sample with highest content of ZrO2. The oxygen packing density (OPD) rises from 74,742 to 82,980 kg atom/m3 when increasing content of ZrO2 from 0 to 6 mol%, respectively. The number of N3 was increased which the number of N4 decreased with ZrO2 concentration which confirms that the decreasing formation of BO4 units with ZrO2 content. Both VL and VS are persistently increasing for all range of the studied samples; such a behavior is ascribed to increments in number of strong Ø’s units. The insertion of ZrO2 in glasses network leads to improve their elastic moduli. Higher values of Debye temperature (θD) are found with increasing ZrO2 content that means higher thermal energy needed for excitation the corresponding vibrational mode. Makishima–Mackenzie values of Young (YM) and bulk (BM) moduli were in good agreement with the experimental results. Therefore, the increasing trends of YM and BM are similar to those of Young (Y) and bulk (B) moduli assuring the effect of [ZrO6]2− on introducing strengthened bonds into borate lattice. In addition, the microhardness (Hv) was found to increase with ZrO2 content; therefore, the glass system gets harder and stiffer. [ABSTRACT FROM AUTHOR]

Six specimens of glasses with formula (70 − x)B2O3/15Li2O/15ZnO/xY2O3: x = 0.0, 0.5, 1.0, 1.5, 2.0, and 2.5 mol%) have been synthesized via a conventional melt quenching technique. The produced specimens were named as BLZY0.0–BLZY2.5 according to x values. The physical, ultrasonic longitudinal (VL) and shear (VS) velocities, FTIR, and dielectric (50 Hz to 5 MHz) characteristics of the prepared glasses have been examined. With increasing content of Y2O3 from 0.0 to 2.5 mol%, the density (ρ) of the system increases linearly from 2512 ± 11 to 2695 ± 14 kg/m3, while the molar volume (VM) decreases linearly from 2.6 ± 0.011 to 2.57 ± 0.013 × 10−5 m3/mol. The oxygen packing density (OPD) as a number of the oxygen per unit composition in the glass sample is describing the packing tightness of the oxide network and thoroughly the compactness of the glass matrix. Values of the average boron–boron separation (dB–B) decrease from 4.162 to 4.035 × 10−10 (m) with 0 to 2.5 mol% Y2O3. Increasing formation of Y3+ ionic bonds with [BO4/2]1− may have an effect of lowering bond strength of B–O and thus shifting the absorption IR peak position. By increasing Y2O3 content in the investigated samples, the (VL) and (VS) increase linearly for the full-studied compositional range. The increasing number of strengthened bonds due to change coordination of B ions from 3 to 4 due to the increasing field strength of inserted accumulated Y3+ ions has the incentive impact to higher mechanical properties. The dielectric constant was decreased for Y2O3 content up to 1.5 mol% referring to cross-linkage formation with other elements, while the reduction in porosity at high content of Y2O3 is the main responsible for gradual enhancement in dielectric constant. [ABSTRACT FROM AUTHOR]

Background: The management of early breast cancer (BC) has witnessed an uprise in the use of neoadjuvant therapy and a remarkable reshaping of the systemic therapy postneoadjuvant treatment in the last few years, with the evolution of many controversial clinical situations that require consensus., Methods: During the 14th Breast-Gynecological and Immuno-Oncology International Cancer Conference held in Egypt in 2022, a panel of 44 BC experts from 13 countries voted on statements concerning debatable challenges in the neo/adjuvant treatment setting. The recommendations were subsequently updated based on the most recent data emerging. A modified Delphi approach was used to develop this consensus. A consensus was achieved when ≥75% of voters selected an answer., Results and Conclusions: The consensus recommendations addressed different escalation and de-escalation strategies in the setting of neoadjuvant therapy for early BC. The recommendations recapitulate the available clinical evidence and expert opinion to individualize patient management and optimize therapy outcomes. Consensus was reached in 63% of the statements (52/83), and the rationale behind each statement was clarified., (© 2024 American Cancer Society.)