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This paper demonstrates the possibility of improving the γ-photons attenuation traits of a new type of borosilicate glass system (x)PbO: 0.12B2O3:(0.8-x) SiO2: 0.08K2O (where: x = 0, 0.05, 0.15, 0.3, 0.5 wt.) prepared using various doping concentrations of PbO. The mass attenuation coefficient (µ/ρ) of the proposed glass system over the entire γ-photon energy range (0.005–3 MeV) was improved due to doping. Glass with the highest doping concentration achieved the optimum values for µ/ρ, µ, αa, Zeff and Neff. The lowest values of MFP and HVL for the glasses were observed in the mid γ-photons energy region. In addition, the RPE values of the glasses were significantly enhanced with the increase in PbO content and reduced with the increase of γ-photons energy. The computed values of various radiative parameters like µ/ρ, µ, MFP, RPE, HVL, αa, Zeff. and Neff derived from XMuDat and XCOM programs were in good agreement with the theoretical values acquired using the Phy-X software. The proposed glass system may be useful as a high-performance radiation shield. [ABSTRACT FROM AUTHOR]

Rare earth ions-doped oxide glasses with improved traits are needed for sundry applications. Based on this fact, physiochemical and magnetic characteristics of Er3+ -doped lead–tellurite glasses embedded with gold nanoshapes (Au-NSPs) were customized via preparation and characterization. Glasses of composition 78.95TeO2–15PbO–5PbCl2–1Er2O3–0.05AuCl3 were made using conventional melt-quenching techniques at varying (1, 6, 16, and 24 h) heat treatment durations (HTDs) to optimize their morphology, structure, chemical, and magnetic properties. Structure analysis verified the amorphous nature of the as-quenched samples and the homogeneous distribution of Au-NSPs within a network matrix with an average diameter ranged from 1.32 to 7.12 nm. Significant chemical functional groups of the glasses were detected at 360 and 598 cm‒1, attributed to the number of non-bridging oxygen (NBO) in glass and the conversion of TeO4 tbp into TeO3 polyhedra through TeO3+1. The magnetic behavior of the glasses was due to the diffusion-limited growth of Au-NSPs as evidenced from the ESR and VSM results. Saturation magnetization and magnetic coercivity were in the range of 4.61 × 10–2 to 10.614 × 102 emu/g) and 1441.60 to 1992.20 Oe, respectively. The variations of g-factor, resonant magnetic field, and peak-to-peak line-width of the glasses were established to be promising for various functional applications especially for biomedical devices as antiviral screen protectors. [ABSTRACT FROM AUTHOR]

Silica-titania (ST) nanohybrid and bromophenol blue (BPB) immobilized ST nanohybrid matrix are synthesized by low-temperature sol-gel route. The influence of BPB on the structural, morphological, and nonlinear optical properties of silica-titania nanohybrid was investigated by fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), atomic force microscopy (AFM), and z-scan technique. FTIR analysis confirms the chemical bonding between hydrophobic BPB dye species and hydrophilic type ST nanohybrid matrix. TEM and AFM analysis shows that the synthesized immobilized nanohybrid has inter-dispersed structure with average particle size of 0.8 ± 0.3 nm, smooth morphology, and low average surface roughness ~4.57 nm. The immobilization of BPB greatly improves the nonlinear refraction response and the nonlinear refractive index increases from 4.8 × 10-9 cm2/W to 451.9 × 10-9 cm2/W. Reverse saturable absorption is observed in both BPB and BPB/ST nanohybrid. However, the magnitude of nonlinear absorption coefficient in BPB/ST is lower than the BPB dye due to the occurrence of saturable absorption of the ST matrix. The optical limiting (OL) behavior of the BPB/ST nanohybrid reveals the low OL threshold at 0.33 kW/cm2. The synthesized BPB/ST nanohybrid has potential as an optical limiters for safety of photonic and optoelectronic devices under low-powered CW laser.Bromophenol blue (BPB) immobilized silica-titania nanohybrid has been synthesized. FTIR analysis confirms the immobilization between hydrophobic BPB dye species and hydrophilic type ST nanohybrid matrix. The BPB/ST nanohybrid shows the inter-dispersed structure with homogeneous surface. The superior nonlinear refraction response and the nonlinear refractive index 4.52 × 10-7 cm2/W is obtained. The optical limiting action starts at low threshold, 0.33 kW/cm2 Synthesis of silica-titania (ST) nanohybrid and bromophenol blue (BPB) immobilized ST nanohybrid matrix by sol-gel method is reported.FTIR analysis confirms the chemical bonding between hydrophobic BPB dye species and hydrophilic type ST nanohybrid matrix.TEM and AFM analysis shows the inter-dispersed structure with low average surface roughness ~4.57 nm.The superior nonlinear refraction response and the nonlinear refractive index 4.52 × 10-7 cm2/W is obtained.The optical limiting (OL) behavior revealed the low OL threshold at 0.33 kW/cm2.The synthesized BPB-ST nanohybrid has potential as an optical limiters for safety of photonic and optoelectronic devices under low-powered CW laser. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study is to compare the effect of treated dentine matrix (TDM) and tricalcium phosphate (TCP) scaffolds on odontogenic differentiation and mineralization of dental pulp stem cells (DPSCs) in furcation perforations created in the pulp chamber floor of premolar teeth in dogs. Material and methods: DPSCs were isolated and cultured from the dental pulp of the maxillary left second and third premolars of dogs. The DPSCs were loaded on TCP (SC+TCP) and TDM (SC+TDM) scaffolds and inserted into intentionally perforated pulp chamber floors of premolars in dogs; six teeth were used for each group. Three more groups of six specimens were created, and mineral trioxide aggregate (MTA), TDM, and TCP were inserted into the perforations to act as controls. An intact premolar and no treatment in the perforation site were used as positive and negative controls respectively. After 3 months, the animals were sacrificed and the type of inflammation, presence of dentine, continuation and type of cementum, type of connective tissue, and presence of foreign body reaction were evaluated, and significant differences were between groups determined using the Fisher's exact test. The evaluation of the amount of inflammation and the percentage of new bone formation was evaluated using the Mann-Whitney U test. Results: The negative control group was associated with severe inflammation and granulation tissue formation. In the positive control group, intact periodontal tissues and no inflammation were observed. Dentine bridge formation was not seen in specimens of any group. The specimens in the SC+TDM group were associated with significantly more bone formation than other groups ( P < 0.001). The amount of inflammation was less than 10 % in specimens of all groups with the exception of three specimens in the TCP group that were categorized as 10-30 %. Chronic inflammation without foreign body reactions was the major pattern of inflammation in groups. Formation of cementum with a cellular and continuous appearance was seen in all specimens. Conclusions: SC+TDM was associated with significantly more bone formation when used to repair uninfected furcation perforations in the premolar teeth of dogs. Clinical relevance: Application of TDM as a biological scaffold in combination with DPSCs may offer an advantage during the repair of root perforation defects. [ABSTRACT FROM AUTHOR]

The Paleocene-Early Eocene Sachun Formation across the interior Fars in the SE of the Zagros Basin (Iran) consists of carbonates, evaporites and siliciclastic sediments. Lithostratigraphic evidence shows that the Sachun Formation can be divided into three units: lower evaporite (unit 1), middle limestone and marl (unit 2), and upper evaporite (unit 3). The lower and upper evaporate units are represented by gypsum-anhydrite layers that are interbedded with thin-bedded dolomite and red marl layers. In the evaporites of the Sachun Formation, brecciated gypsum, nodular, nodular-banded gypsum and laminated-banded gypsum with chicken-wire fabrics are identified. These associations indicate a sabkha or shallow-water setting, such as a lagoon. Petrographic studies led to the identification of twelve carbonate facies types that have been formed in four different types of depositional settings, across a ramp with a gentle dip, including; supratidal sabkha, shallow subtidal lagoons, barrier and shallow open-marine. The mixed carbonate and siliciclastic lithofacies are composed of red and gray marl which both are interbedded with carbonate and evaporite deposits. Three depositional sequences (A, B and C) are recognized from deepening to shallowing trends in the depositional facies, changes in cycle stacking patterns and sequence boundary features. Sequences A and C are evaporite-dominated shallowing-upward cycles and sequence B consists of carbonate-dominated shallowing-upward cycles. [ABSTRACT FROM AUTHOR]

Colloidal suspension of alloy nanoparticles has been prepared and their third-order nonlinear optical response was investigated by means of the Z-scan technique, employing 532 nm continuous wave laser excitation. Alloys colloidal suspension of industrial grade brass, aluminium, and copper was prepared via laser ablation in liquid technique. FESEM analysis reveals the particles size of less than 102.33 nm on average. The magnitude and sign of the nonlinear refraction, n2 and nonlinear absorption, β were determined. It was observed from the closed aperture Z-scan that all the suspensions exhibited a self-focusing effect with a negative nonlinear refractive index, n2, attributed to thermal lensing effect. Colloids of brass possess highest n2 followed by copper and aluminium suspension, attributed to the thermally agitated process whereby heat is transferred into non-local region of the propagation axis. Open Z-scan results revealed that the brass suspension exhibited saturable absorption (SA) with significant negative β value. Aluminium and copper alloy NPs suspension rather shows reverse saturable absorption with a positive β value. These materials were found to exhibit significant nonlinear refraction and nonlinear absorption behaviour, making them possible candidates for photonic and/or optoelectronic applications, especially with low powered continuous wave laser excitation. [ABSTRACT FROM AUTHOR]

In preclinical studies, p53 loss of function impacts chemotherapy response, but this has not been consistently validated clinically. We trained a TP53-loss phenocopy gene expression signature from pan-cancer clinical samples in the TCGA. In vitro, the TP53-loss phenocopy signature predicted chemotherapy response across cancer types. In a clinical dataset of 3003 breast cancer samples treated with neoadjuvant chemotherapy, the TP53-loss phenocopy samples were 56% more likely to have a pathologic complete response (pCR), with a significant association between TP53-loss phenocopy and pCR in both ER positive and ER negative tumors. In an independent clinical validation in the I-SPY2 trial (N = 987), we confirmed the association with neoadjuvant chemotherapy pCR and found higher rates of chemoimmunotherapy response in TP53-loss phenocopy tumors compared to non-TP53-loss phenocopy tumors (64% vs. 28%). The TP53-loss phenocopy signature predicts chemotherapy response across cancer types in vitro, and in a proof-of-concept clinical validation is associated with neoadjuvant chemotherapy response across multiple clinical breast cancer cohorts., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)