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Development of next-generation photonic device necessitates employing vitreous materials with high optical nonlinearities and low optical limiting thresholds. Additionally, the high nonlinear photonic glasses are suitable for nuclear radiation shielding applications. Herein, the borate-based glass specimens bearing significant amounts of heavy metal oxides (Bi.sub.2O.sub.3 and PbO) activated with various quantities of Eu.sub.2O.sub.3 have been explored for optical limiting, nonlinear photonic, and nuclear radiation shielding applications. Efficacy of Eu.sub.2O.sub.3 content on functional features has been assessed and discussed the outcomes in detail. The open aperture Z-scan results unveiled the enhancement in two-photon absorption coefficient and reduction in optical limiting threshold with Eu.sub.2O.sub.3 amount in the glass composition. Further, certain fundamental attenuation factors such as mass attenuation and linear attenuation coefficients were estimated utilizing Phy-X software in the energy ranges between 0.284 and 2.506 MeV. The mass attenuation and the linear attenuation coefficients were found to improve with the inclusion of more and more Eu.sub.2O.sub.3 in the glass compositions. The outcomes of the study clearly revealed that the high Eu.sub.2O.sub.3 activated lanthanum heavy metal borate glasses are productive in optical limiting, nonlinear optical, and gamma radiation shielding strategies to cutoff the high energy electromagnetic and nuclear radiations. The comparative study further validates that the La.sub.2O.sub.3-Bi.sub.2O.sub.3-B.sub.2O.sub.3-Eu.sub.2O.sub.3 glasses are more advantageous than La.sub.2O.sub.3-PbO-B.sub.2O.sub.3-Eu.sub.2O.sub.3 glasses.

Development of next-generation photonic device necessitates employing vitreous materials with high optical nonlinearities and low optical limiting thresholds. Additionally, the high nonlinear photonic glasses are suitable for nuclear radiation shielding applications. Herein, the borate-based glass specimens bearing significant amounts of heavy metal oxides (Bi 2 O 3 and PbO) activated with various quantities of Eu 2 O 3 have been explored for optical limiting, nonlinear photonic, and nuclear radiation shielding applications. Efficacy of Eu 2 O 3 content on functional features has been assessed and discussed the outcomes in detail. The open aperture Z-scan results unveiled the enhancement in two-photon absorption coefficient and reduction in optical limiting threshold with Eu 2 O 3 amount in the glass composition. Further, certain fundamental attenuation factors such as mass attenuation and linear attenuation coefficients were estimated utilizing Phy–X software in the energy ranges between 0.284 and 2.506 MeV. The mass attenuation and the linear attenuation coefficients were found to improve with the inclusion of more and more Eu 2 O 3 in the glass compositions. The outcomes of the study clearly revealed that the high Eu 2 O 3 activated lanthanum heavy metal borate glasses are productive in optical limiting, nonlinear optical, and gamma radiation shielding strategies to cutoff the high energy electromagnetic and nuclear radiations. The comparative study further validates that the La 2 O 3 –Bi 2 O 3 –B 2 O 3 –Eu 2 O 3 glasses are more advantageous than La 2 O 3 –PbO–B 2 O 3 –Eu 2 O 3 glasses.

For the near-infrared emission, Er3+ and Er3+/Yb3+ co-activated borate based glass hosts were synthesized by the method of melting andquenching. The emission intensity was maximum for 0.5 mol% Er3+ singly activated glass in the near-infrared (NIR) region covering the telecommunication window. The 2 mol% of Yb3+ co-doping enhanced the emission gain cross-section of the glass by two times contrast to 0.5 mol% Er3+ loaded glass. This enhancement shifted to lower spectral regions when P increased from 0 to 1. The effect of Yb3+ loading on the gain cross-section of the Er3+ co-activated glasses was analyzed using the McCumber theory. The results showed that the 0.5Er2Yb glass has a flat gain in the range of 1460–1640 nm, this suggest a lower pump threshold is enough to perform the laser functioning of a 1530 nm band and optical window of telecommunication applications.

The lanthanum sodium borate glass of composition x Sm 2 O 3 - y AgCl-(80- x - y )B 2 O 3 –15 Na 2 O-5La 2 O 3 (where x  = 0.5 and y  = 0.1 mol %) was prepared and heat treated at a constant temperature of 450° C with different annealing schedules of 10, 20 and 30 h durations to enable the formation and growth of the Ag nanoparticles. Transmission electron microscope measurements revealed the existence of Ag nanoparticles in the examined glass specimen. The strong red emission was observed for 4 G 5/2  →  6 H 7/2 inherent transition of samarium ions in the titled glass samples. The robust emission and excitation intensities of Sm 3+ ions are at 10 h annealing durations, and then decrease with increasing annealing durations due to the quenching effect. The transition and radiative properties of various excited levels of Sm 3+ in the titled glass series were estimated, including the branching ratios, stimulated emission cross-section, radiative lifetime, and radiative transition probabilities. The improved luminescence results and better JO features for the 4 G 5/2  →  6 H 7/2 emission transition suggest the glass specimens routed with Ag nanoparticles are beneficial for optoelectronic and photonic applications.

Herein, the nonlinear optical (NLO) and optical limiting (OL) features of silver nanoparticles (NPs) and holmium ions containing borate-based glasses bearing the nominal composition (79– x )B 2 O 3 –15Na 2 O–5La 2 O 3 –1Ho 2 O 3 – x AgCl ( x  = 0, 0.1, 0.25, 0.5, and 0.75 mol%) were deliberated at 532 nm pumping utilizing the nanosecond laser pulses. We studied the NLO and OL characteristics of AgCl content varied glasses and identified that the Ho 3+ -doped glasses containing 0.5 mol% of AgCl was found to be optimized one. Then, for further tuning of the NLO traits, thermal treatment on optimized glass was carried out at 450 °C for diverse durations. The NLO absorption (two‒photon) and refraction (positive) features were noted to improve with AgCl content and thermal treatment duration, while the OL threshold followed an opposite trend. The enhance of NLO characteristics and OL performance of glasses was resulted on account of local field effect. The outcomes of the study endorse the Ho 3+ ‒doped titled glass containing 0.5 mol% of AgCl thermally treated for 35 h at 450 °C is beneficial for data storage, signal processing and harmonic generation functionalities. Additionally, the enhance of NLO absorption along with decrease of OL threshold results acknowledge the same glass system is useful for OL applications for suppressing high energy coherent radiation in protecting the sensitive optical devices and human eye from laser damage.

20Li 2 O-15CaF 2 -20ZnO-45B 2 O 3 - 0.XAu-(0.5-X) Ag, (where X= 0.2, 0.3) glasses were prepared by the conventional melt quench technique and coded as 2G3S and 3G2S respectively. The idea of this current work is to check the compositional dependence on the gold and silver nanoparticles in the glass. The XRD results confirmed presence of Au-Ag (111) peak at 38.11. The Infrared spectral study confirms the presence of borate segments. The UV Visible Spectroscopic studies confirms the presence of surface plasmon resonance shoulder peak for Ag nanoparticles around 490nm and 509 nm for glass 2G3S and 3G2S which had overlapped with SPR resonance peak of Au around 603 nm for glass 2G3S and around 559nm for glass 3G2S. The nonlinear optical properties were characterized using Z-Scan experimental technique for these glasses and it suggests the Glass 3G2S exhibited better nonlinear refractive index and nonlinear absorption coefficient compared to Glass 2G3S

Holmium doped 10La2O3-15Bi2O3-(75-x) B2O3 (Ho3+: LBB) glasses have been prepared by melt quench technique and the impact of holmium ions concentration on optical and physical properties of present glasses have been examined. Ho3+ dependent density, molar volume, refractive index, rare earth ion concentration, polaron radius, inter ionic distance, field strength and energy band gap are calculated and tabulated. Amorphous nature of the all glasses has been confirmed by XRD patterns. The room temperature (RT) Uv-Vis absorption spectrum doped with 1 mol% of Ho2O3 exhibit eight prominent bands centred at 895, 641, 537, 486, 472, 467, 451 and 416 due to transition between ground state to various excited states. The results show that, the density is increases and molar volume of the glasses is decreases with an increase in Ho2O3 concentration and consequently generate more non-bridging oxygen (NBOs) in the glass matrix. The Urbach energy is increases with holmium concentration which exemplifies the degree of disorder present in the LBB glasses. The considerable increase in field strength observed in present glasses is attributed to occurrence of strong bridge between Ho3+ and B- ions and this strong bridge is possibly due to the displacement between Ho3+ and oxygen atoms which are generated from the conversion BO3-BO4 units.

The reports in the literature on effects of diabetes on mitochondrial energy-linked functions are conflicting. Hence we carried out systematic studies to evaluate the effects at the early and the late stages of the disease using STZ-diabetic rat as a model. At the end of one week, after induction of diabetes, respiration rates with glutamate and succinate as the substrates increased; respiration rates with other substrates e.g. β-hydroxybutyrate, pyruvate + malate and ascorbate + TMPD were not affected despite substantial decrease in the β-hydroxybutyrate dehydrogenase activity and cytochrome b and c+c(1) contents. Insulin treatment brought about increase in the cytochrome contents beyond control values. The ATPase activity was generally low in the diabetic animals and was not restored by insulin treatment.At the end of one month, the respiratory activities with all the substrates were generally low. Insulin treatment either restored or stimulated the respiration rates beyond control values. The content of cytochromes was differentially affected in the diabetic animals, but insulin treatment caused significant increase beyond control levels. The pattern for ATPase activity was similar to the early effects.At both the stages i.e. early and late stages of diabetes the mitochondria were tightly coupled. The ADP/O ratios were in normal expected ranges and the respiratory control ratios were comparable with the control groups. Insulin treatment resulted in apparent restoration of respiratory activity. However, the effects on the cytochromes and dehydrogenases activities were differential. Taken together the two observations would suggest that the mitochondria were not re-instated to normality despite apparent restoration of respiratory function.

To assess salivary levels of cariogenic bacteria namely Streptococcus mutans and Lactobacillus acidophilus as well as caries experience in mothers (Group IM) and children with ECC (Group IC) in comparison to caries free children (Group DC) and their corresponding mothers (Group IIM). Sixty pre-school children (3-5 years) and their mothers were included and matching was done. The study group consisted of 30 children with ECC and a control group comprising of 30 caries free children. Children together with their mothers were examined for their caries experience and microbiological assessment of their saliva was carried out. Statistical analysis was done using S.P.S.S version 15.0 software. Statistical tests used were Chi Square and t-test to determine the strength of association between the variables. Streptococcus mutans was significantly higher in children of ECC (Group IC) than caries free children (Group DC) (p<0.001). Lactobacillus acidophilus was significantly higher in group IC and group IM than caries free children (Group IIC) and their corresponding mothers (Group IIM). There was no significant difference in Streptococcus mutans count in Groups IM and IIM. Significant association was observed in the proportion of children in the ECC group and their mothers with respect to levels of Streptococcus mutans indicating vertical transmission.