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In an attempt to cultivate energy‐stability balance, a series of nitrogen and oxygen‐rich high energy density materials were synthesized based on N‐substituted 4‐hydroxy‐3,5‐dinitropyrazole and methylene‐linked N‐amino‐1,2,4‐bridges. The hydroxy substituent contributed to oxygen content, hydrogen bonding, and tunability via salt formation. On the other hand, the triazole bridge delivered high nitrogen content and thermal stability. All the synthesized compounds were characterized with multinuclear NMR, FTIR, HRMS, and elemental analysis, and their physicochemical and energetic properties were analyzed. Energetic materials 1–5 showed high detonation performance and adequate overall stabilities. Compound 1 exhibited higher density (1.84 g/cm3) and detonation performance (Dv = 8103 m/s, P = 26.9 GPa) in comparison to its reported amino derivative. [ABSTRACT FROM AUTHOR]

With an aim to improve the overall physical stability of high-performing 3,5-dinitro-functionalised bispyrazolymethanes, a hydroxyl functionality was introduced at the fourth position to obtain 1,1′-methylenebis(3,5-dinitro-1H-pyrazol-4-ol) and its energetic salts. Superior oxygen balance and energy in comparison to the amino substituent at the 4th position and enhanced sensitivity with respect to the nitro and azido substituents helped in unlocking the potential of less explored N-alkylated-4-hydroxy-3,5-dinitropyrazoles. Fine-tuning of properties via dicationic salt formation, which is not feasible in any other reported symmetrically connected pyrazole-based energetic materials, resulted in improved physical and thermal stabilities, as well as energetic performance. Hirshfeld surface analysis, electrostatic potential analysis, the study of aromaticity and weakest Mayer-bond order analysis helped further in studying the structure–property relationship of the synthesized compounds with respect to different reported methylene-bridged symmetrical compounds. [ABSTRACT FROM AUTHOR]

Introduction -- Indirect restorations are frequently luted to the remaining tooth structure with new age self-adhesive resin cements. Use of these advanced single step cements reduce chair side time for the clinician. In clinical practice it is not possible to achieve complete isolation in the oral cavity. Contamination during bonding procedures is inevitable, however shorter the time taken to perform the bonding procedure more effective the moisture control by conventional means. This contamination may alter the binding capacity of the cement to the dentine and thus affect the retention of the prosthesis. Aim -- To compare and evaluate the Shear Bond Strength of Two Self adhesive Resin Cements and Dentin with and without salivary fluid contamination. The null hypothesis states that there is no difference exists in the SBS after salivary contamination at the dentine interface. Materials and Method -- 40 freshly extracted premolar teeth were grounded occlusally and embedded in acrylic blocks. The 40 blocks were randomized into 4 groups. Each group was bonded with either resin cement before or after salivary contamination. All samples were tested using the Universal Testing Machine at a cross head speed of 0.5mm/min. The force of dislodging was noted. The data was then subjected to paired and unpaired t test. Results -- On analysis no statistically difference in SBS was noted between A1,B1 and A2,B2. On comparing the groups A1 and A2(after salivary contamination) and B1 and B2(after salivary contamination) p<0.05 was noted which was of statistical significance. Conclusion -Salivary Contamination reduced the SBS between the resin cements and dentin. The individual resin cements showed no statistical difference in shear bond strength. [ABSTRACT FROM AUTHOR]

Total glossectomy defects resulting from postoncologic resection are commonly reconstructed with locoregional or free flaps. However, effectively managing complications that may arise after reconstruction can be a significant challenge. We present a unique case series describing prosthetic management of flap-related complications following glossectomy in patients treated for locally advanced tongue cancer. Three patients underwent total glossectomy, neck dissection, reconstruction using free flap, and tracheostomy. Two patients developed an intraoral fistula located in the anterior region of the floor of the mouth. The third patient developed a flap failure requiring a second procedure using a pectoralis major myocutaneous flap for correction of the orocutaneous fistula that ultimately did not heal. Mandibular obturator prostheses lined with a soft liner were fabricated for all the patients, which helped reduce salivary incontinence and improve swallowing and speech. This case series highlights that a collaborative interdisciplinary team approach is crucial for optimizing postoperative function and outcomes when managing complications from reconstructive procedures. [ABSTRACT FROM AUTHOR]

Magneto-fluorescent nanoparticles have attracted great attention because of their dual nature as multimodal imaging probes in various biomedical applications. Particulary, it is desirable to understand how these nanoparticles interact with human serum proteins before they are used in biological systems. In this work, the physiological interactions between magneto-fluorescent nanoparticles (MFNPs) and bovine serum albumin (BSA) were systematically investigated. The present observations identified that the collision of MFNPs and BSA caused fluorescence quenching of BSA. Steady state fluorescence, lifetime and anisotropy measurements in the presence of MFNPs supported dynamic quenching of the BSA emission. Furthermore, in the presence of MFNPs, the conformation changes in the BSA structure indicate merely the secondary structural changes. The findings demonstrated that random interactions and hydrophobic forces play a major role in the dynamic quenching. Further, subsequent coating of BSA over MFNPs result in protein corona formation, as is evident through spectroscopic measurements. In light of the present work, MFNPs could serve a purpose in magnetic separation and optical detection of serum proteins from blood plasma in real-time disease diagnosis. [ABSTRACT FROM AUTHOR]