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The insulators used in power transmission and distribution networks should withstand abnormal system-generated switching impulses and natural lightning impulses. To avoid the failure of insulators in the field, the impulse puncture strength evaluation of the ceramic insulators is important. IEC 61211 standard stipulates the procedure to evaluate the ceramic disc insulators’ strength to withstand steep front impulses. In this test, the test voltage is determined by using a short standard string of five insulators. This paper presents the variation in the impulse stresses across the disc insulator units in the string due to non-linear voltage distribution under impulse flashover. This paper also correlates the test voltage values defined by the IEC standard with the highest stress on insulator units under impulse flashover of string insulators by using voltage distribution. The correlation study has been carried out with insulator strings having different arcing distances by using a different number of units.

The present work reports the physical, structural, elastic, optical, and radiation shielding studies on (80˗X)H3BO3+10TeO2+9.5Nb2O5+XBaO+0.5Sm2O3 (where X = 10, 20, 30, 40, 50 in wt%) glasses which is prepared by the melt quenching technique. The bending and stretching vibrations of the different compounds used are analyzed through FTIR instrumentation. The density and refractive indices are measured experimentally following Archimedes's principles and by using Abbe's refractometer, respectively. Various structural parameters are calculated to resolve the actual placement of atoms in the glass complex, which explains the compactness of the network. Elastic properties of the synthesized glasses are calculated to estimate the resistance of glass under stress. Additionally, the optical band gap is calculated, and the nature of bonds in the network is ionic compared to the covalent nature. Boron–Boron distance is the lowest for 50BNTBSm sample. The decrease in OPD content is linked with the decrease in the number of oxygen atoms, for 10BNTBSm and 50BNTBSm glasses, it is 289 and 209 oxygen atoms, respectively. Λth value is high for 10BNTBSm glass sample with the minimum BaO reinforcement. The Urbach's energy varies from 0.534 to 0.967 eV, corresponding to xBNTBSm samples indicating fewer defects in the glasses. Moreover, gamma-ray and fast neutron attenuation properties of xBNTBSm are determined and compared with numerous shielding materials such as concrete and other types of glasses. Results showed that replacing 40% of H3BO3 with BaO leads to a net improvement in gamma-ray attenuation properties. However, this situation was the opposite in the fast neutron absorption properties. A clear superiority of sample 50BNTBSm was also reported against the compared absorbent materials. It can be concluded that replacing 40% of H3BO3 with BaO would provide some significant improvements to Niobium Bariumtelluroborate glasses. WOS:000860344800007 Q1

A systematic study of structural, thermal, linear, and non-linear optical properties on 60TeO2–20ZnO–(16 − x)BaCO3–4BaF2–xTm2O3 (x = 0.25 to 2 mol%) glasses synthesized by melt-quenching technique is reported. Thermal stability of the samples was found to be around 100 °C, while their energy bandgap values varied between 3.08 and 3.57 eV. Measured properties showed a dominant effect of thulium ions in modifying the properties of the glassy matrix. Structural studies using Raman spectroscopy showed the presence of non-bridging oxygen (NBO) dominated by the matrix effect and also aided by the rare earth dopants, while the presence of hydroxyl impurities was elucidated from infrared spectroscopy. Optical absorption spectra showed characteristic thulium bands and the increment in spectroscopic quality factor calculated from measured absorption data indicating the lasing capability of the material. Luminescence spectra yielded two strong 3H4 → 3F4 and 3F4 → 3H6 emission transitions in the infrared region around 1460 nm and 1863 nm for all the samples, intensities of which were affected by increasing rare earth concentrations. Open aperture Z-Scan measurements indicated a reverse saturable absorption behavior for all the samples owing to two-photon absorption. Formation of more NBO led to the reduction of optical limiting threshold values from 3.91 × 1012 to 2.38 × 1012 W/m2 with thulium doping which indicated that this glass can be tuned to act as mid-infrared source as well as excellent optical limiter.

CNS Melioidosis is a rare and complicated form of Melioidosis with a mortality rate of up to 50%. We hereby present a case of CNS Melioidosis with bacteremia and pulmonary manifestations of Melioidosis based on CT Chest imaging ndings, who on prompt initiation of appropriate IV antibiotic therapy along with craniotomy and drainage of cerebral abscess showed drastic recovery. This indolent multi systemic presentation along with the rarity of CNS Melioidosis in general, makes this case report note-worthy.

Introduction Inflammation induces changes in muscle protein turnover and mass and dampens insulin stimulated glucose disposal and oxidation. Limited information is available regarding the molecular regulation of these events. We determined the acute effects of lipopolysaccharide (LPS) infusion on targeted muscle mRNA expression. Methods Seven healthy, males (age 21.9±0.6 yrs, BMI 23.4±1.2 kg.m-2) participated in this ethically approved randomised crossover design study. On 2 occasions separated by >2 weeks, subjects underwent a 4h hyperinsulinaemic euglycaemic clamp combined with a primed mixed amino-acid (6 g.h-1; to create a ‘fed-state’) infusion, immediately following bolus saline (control) or LPS (4 ng.kg-1) infusion. Vastus lateralis muscle biopsies were obtained at baseline, 120 and 240 min. Muscle mRNA expression was measured (191 targets deemed to be representative of insulin sensitivity, carbohydrate and fat metabolism, inflammation, and protein turnover) using microfluidics TaqMan array cards. Results Plasma [TNF alpha] was markedly elevated above control following 60 min of LPS infusion (P1.5 fold change in muscle mRNA expression from baseline, P Conclusion Muscle mRNAs respond rapidly to insulin and amino acid infusion in humans, but the magnitude of response was greater in the presence of LPS and may underpin changes in muscle protein and fuel metabolism seen under these conditions. Take-home message Endotoxaemia acts rapidly (within 2 to 4 hours) to alter the expression levels of muscle mRNAs known to be intimately involved in the molecular regulation of muscle mass, insulin resistance and fuel oxidation in human volunteers under controlled conditions of insulin and nutrient availability. This may play a role in the changes in muscle metabolism seen under such conditions.

Five new strontium barium borate (BNBD) glasses doped with dysprosium ion and different concentrations of niobium pentoxide were synthesized using the standard melt-quenching method. The physical, structural, optical and gamma radiation shielding properties of these glasses were investigated. Density, average molecular weight, refractive index, molar volume, optical dielectric constant, boron-boron separation, metallization criterion, oxygen packing density, Poisson ratio, optical basicity, optical electronegativity, and two-photon absorption coefficients of the synthesized glasses were determined. By the addition of Nb2O5 content, boron-boron distance and oxygen packing density values increased, while molar volume of oxygen decreased due to the formation of bridging oxygen. The two-photon absorption could be constrained by replacing BaCO3 by niobium pentoxide content which further influences the bandgap. The ionic nature of the titled glasses is discussed using the bonding parameter, optical basicity, ionic and covalent characteristic parameter values. Moreover, the shielding ability of dysprosium ions doped niobium borate glasses against photons, fast neutrons and electrons has been extensively evaluated. For this purpose, the mass attenuation coefficient (µ/ρ, cm2/g) of the glasses and several photon protection parameters, derived from µ/ρ were obtained for 0.015–15 meV. The maximum µ/ρ values were achieved for BNBD0 glass, varying between 0.033 and 35.430 cm2/g. The lowest buildup factor values were found for BNBD0 glass. Furthermore, effective removal cross section values for fast neutrons increased steadily between 0.125 and 0.130 cm−1 due to the increase in the density of the glasses with the enhancing of Nb2O5 concentration. It was noticed that the range of high energy electrons was shorter on the BNBD0 glass. It was concluded that BNBD0 glass with high BaCO3 concentration can be considered as an alternative material in nuclear radiation shielding applications.

This paper deals with the new classes $\mathcal{S}^{\ast}_{\cos}$ and $\mathcal{S}^{\,\mathbf{c}}_{\cos}$ of starlike and convex functions, respectively, associated with the cosine function. We give initial coefficient bounds for the first seven coefficients of the functions that belong to these classes, and we evaluate the upper bounds for the Hankel determinant of order three and four. We found the upper bound of Zalcman functional for the above mentioned classes for the cases $n=3$ and $n=4$, showing that the Zalcman conjecture holds for these values. Moreover, we determined lower and upper bounds for the difference $\vert a_{4}\vert-\vert a_{3}\vert$ of the coefficients for the functions that belong to these classes.

Hydroxyapatite (HAp) is the major inorganic component of natural bone which exhibits better biocompatibility with various kinds of cells and tissues, making it an ideal candidate for dental and orthopedic applications. The naturally extracted HAp (Ca10(PO4)6(OH)2) from fish scale and seashell is exactly matched with the chemical composition of bone minerals. Nowadays, soft chemistry is used for the synthesis of bioceramics such as HAp. This is a chemical route that yields more homogeneous solid-state materials. In this study, the extracted powder from fish scale and seashell was heated in the furnace and maintained at 700°C for 3 hours and the powder was naturally cooled. The derived CaO was used for preparing HAp by the microwave irradiation techniques. The HAp was filled with High-Density Polyethylene (HDPE) in the ratio of 10:3 (Matrix 100 g: Filler 30 g) and composite was fabricated by the injection molding. The functional groups present in the HAp-HDPE specimen was identified using Fourier Transform Infrared (FTIR) spectroscopy analysis. The thermal stability of 30 wt. % HAp-HDPE composite was analyzed using Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). In vitro cytotoxicity studies were carried out using MG63 cell line. In these studies, five different volumes of liquid extracts of the prepared HAp-HDPE specimen having different concentrations (10, 20, 30, 40, and 50 μl) were allowed to interact with fresh cell culture medium for 24 hours. The cell morphology, cell viability, and the levels of cytotoxicity of the composite specimen were studied as per 10993:12, and ISO 10993:5 test standards.

A sequence of Sm3+-incorporated calcium telluro-fluoroborate glasses by changing the modifier oxide was prepared via the melt-quenching method. The physical, structural, and gamma radiation shielding properties are investigated. XRD spectra confirmed the glassy state. The glasses’ compactness was explored via the structural features like the boron-boron separation, oxygen molar volume, and oxygen packing density. Mechanical and optical properties such as Poisson’s ratio, optical electronegativity, optical basicity, two-photon absorption (TPA) coefficient, and ionic and covalent characters were evaluated and discussed per modifier concentration. The photon attenuation attributes of the glasses were computed by means of the MCNP-5 code. The mass attenuation coefficient (MAC) was simulated in the energy region of 0.015–15 MeV. The highest MAC achieved at gamma energy 0.015 MeV increased from 25.004 to 33.165 cm2g−1 with increasing the CaO ratios between 0 and 40 wt%. Besides, several attenuation factors, such as the mean free path and the radiation protection efficiency, were evaluated connected with the MAC’s simulated values. The study showed that the fabricated glasses’ radiation protection efficiency at 0.5 MeV increased from 33.39 to 39.31, increasing the CaO content from 0 to 40 mol%.

A new set of bismuth lead borate glasses is synthesized using melt quenching technique with the chemical composition 39B2O3 + 30PbO + 20MO + 10Bi2O3 + 1Eu2O3 (where M = K, Na, Ca, Sr and Ba). Lead based host matrix has been chosen since it acts as an effective material for radiation shielding applications. 30% of Lead oxide is used in every glass along with the varying modifier oxides and the comparative study is reported. The amorphous nature is confirmed via XRD analysis for the synthesized glasses. The physical and structural properties are calculated to get a clear idea about the potentiality of shielding that every glass can withstand. Mechanical strength of the glass is checked by calculating the Poisson’s ratio, since breakage of glasses under stress conditions also need to be tested very much in the nuclear reactors for safety purposes. Optical studies are carried out through UV–Vis absorption spectra and the transitions between the energy levels of Eu3+ ions are reported. By using Tauc’s plot direct and indirect band gap values are calculated along with Urbach energy values. Additionally, the radiation shielding properties of the synthesized glasses are also calculated by using both XCOM and ESTAR programs.

A set of glasses with the composition 29.5B2O3+30TeO2+20MF2+20MO +0.5Dy2O3 (where M = Zn2+, Cd2+, Sr2+, Ba2+ and Pb2+) has been synthesized using a melt quenching technique. The physical and structural properties have been calculated to find out the ability of the glasses to withstand radiation. The optical properties such as optical band gap and Urbach energies of the synthesized glasses have been estimated and were determined to possess minimum defects. MCNP-5 code was applied to evaluate the photon shielding capability of the synthesized glasses. The highest mass attenuation parameter of the sample, 29.5B2O3+30TeO2+20PbF2+20PbO +0.5Dy2O3 (coded as BTD-Pb) varied between 0.202 and 0.040 cm2/g. In addition, the mean free path (MFP) for the prepared glasses has been calculated and observed that the BTD-Pb glass had the lowest MFP, varying between 0.891 and 4.466 cm. Based on the radiation shielding parameters, the BTD-Pb glass sample has the best attenuation ability against gamma rays.

In this investigation the modeling and analysis of dynamic structured Macro-Fiber Composite (MFC) for ambient power has been composed to unimorph and bimorph cantilever beam. The dimensions of the beam and its properties were investigated in order to tip displacement across its length with active and inactive piezoelectric layers of MFC. To optimize structure of a cantilever beam with respect to natural frequency, more effective vibration control that can be achieved with minimum control input. The results show that the dynamic model of the cantilever beam is validated with comparisons of experimental, theoretical data and analytical investigation by using ANSYS Simulation.

Samanea saman (SS) flower particulates were filled in Polylactic acid (PLA) composites were fabricated with different 0, 10, and 20 wt. % through the injection molding process. The elemental composition and morphology of SS PLA composites were studied through FESEM and Energy Dispersive X-ray analysis. Thermal stability of the SS PLA composites specimens was carried out through Thermo Gravimetric Analysis (TGA) and Differential Scanning Calorimeter (DSC). Crystal orientations studied through X-Ray Diffraction (XRD) showed the presence of the orthorhombic SS particulates. The properties of the composites were investigated such as tensile strength, compressive strength, flexural strength, and Shore D Hardness. It was found that 20 wt. % of SS filled PLA composites has a superior tensile strength of 43.76 MPa, the compression strength of 37.94 MPa, the flexural strength of 72.47 MPa, and Shore D Hardness of 80.1 SHN than pure PLA. SS particulates-filled PLA composites would be used for low-strength applications.