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Electrical properties of halide doped tellurium glasses with composition 60TeO 2 -(25-x) Bi 2 O 3 -15B 2 O 3 -x ZnCl 2 , where x varies from 0 to 20 with step-size 5 has been studied in frequency range 10-1 Hz–105 Hz and temperature range of 200°C–300°C. The frequency-dependent conductivity was found to obey Almond-West's universal powers law and parameters such as frequency exponent (s), DC conductivity, and crossover frequency were obtained by fitting the ac conductivity experimental data with Almond-West's universal powers law. Based on estimated s values the electrical conduction model was depicted, and it was found that the correlated barrier hopping (CBH) model provides a pretty realistic depiction of the primary AC conduction mechanism. Further, the migratory enthalpy (H m) and the enthalpy required to remove the cation from its initial position near a charge-compensating centre (H f) were calculated. Further, Variable range hopping, or VRH, was found to be the process by which charges move between localized states. The electric modulus (M″) fitting with the Kohlrausch-Williams-Watts (KWW) function revealed non-Debye-type relaxation in the examined glass samples. Activation energy estimated from conductivity (1.13–1.20 eV), and electric modulus (1.13–1.22 eV) analysis are in good agreement indicating that polarons had to overcome a constant energy barrier throughout both the relaxation and conduction phases. One master curve was produced for all compositions and temperatures as a result of an impressive convergence in the scaling spectra of the AC conductivity and electric modulus (M′ and M″). Therefore, it was concluded that neither temperature nor composition impacted the conduction or relaxation mechanisms seen in the glass samples under study. The dielectric properties studies suggested non-debye type behavior. The figure shows the scaled electric modulus curves for the glass sample (x = 5) at various temperatures as a function of normalized frequency (f/f max). [Display omitted] • Ac conductivity taken at 200–300 °C temperatures and at 10−1-105 Hz frequencies. • Ac Conductivity followed Almond-West's Universal Power Law. • CBH conduction mechanism primary for the frequency exponent (s). • VRH Model applied to present glass samples for conduction mechanism. • The conduction or relaxation processes are unaffected by temperature/composition. [ABSTRACT FROM AUTHOR]

Whole sporozoite vaccine (WSV) approach has been shown to induce efficient CD8 + T cell response, critical for developing of long-lasting sterile protection against Plasmodium . Although WSV was initiated over four decades ago, we still do not fully understand about the absolute requirements for the generation of liver-stage specific CD8 + T memory cells. For more than a decade intravenous (IV) route of immunization has been shown to be protective in pre-clinical studies. However, the intradermal (ID) route is preferred over IV route by many researchers as it is perceived to mimic the natural route of parasite delivery through mosquito bite. Various clinical studies have shown that ID route provokes poor protective responses compared to those seen with IV route of administration. The present study highlights the importance of circumsporozoite (CS) protein in preventing sporozoite entry to the hepatocytes, which however, it is not necessarily sufficient to ensure sterile protection. Instead, this article favors the idea that liver-stage development is a prime requirement for generation of antigen specific CD8 + T cells and suggests the conditions favored by IV inoculation of sporozoite. [ABSTRACT FROM AUTHOR]

Abstract: Kinetics of autothermal reforming (ATR) of tetradecane on Pt–Al2O3 catalyst over the temperature range 750–900°C is investigated. Experimental results obtained from NETL (US-DOE) are used for model parameter estimation and validation. Two Langmuir–Hinshelwood–Hougen–Watson (LHHW) type rate models are developed and subjected to parameter estimation and model discrimination. LHHW model in which hydrocarbon is adsorbed on the catalyst surface as alkyl intermediate species by scission of C–H bond gave physically meaningful parameters. Parameters are estimated by using generalized reduced gradient method in spreadsheet and sequential quadratic programming in Matlab. The estimated parameters for the selected model are thermodynamically consistent. The developed kinetic model could capture the experimental behavior of the process and could predict the outlet composition within 25% error. [Copyright &y& Elsevier]

In this current investigation, a straightforward method is presented for synthesis of Yb-doped SnO 2 (Yb = 0%, 0.5%, 1.5%, 3% and 5%) NPs using a sol-gel approach. Various techniques were used to analyze the surface morphology, crystalline structure, chemical composition, and optical properties of the prepared samples. XRD, FTIR, and HRTEM confirmed nanoparticle formation. Raman, XPS, and PL spectroscopy were employed to examine electronic, optical properties, and lattice defects. Introducing Yb dopant into Yb-SnO 2 NPs enhanced their optical features, as indicated by a significant red shift. These particles exhibited impressive catalytic efficiency, degrading 98% of a 10 ppm RB dye solution within a 60-min period under UV light irradiation. Furthermore, the recyclability analysis demonstrated that the 5% Yb catalyst can be recycled multiple times. Scavenger tests were performed for the 5% Yb sample to explore primary active species involved in the degradation process. The magnetic features of the synthesized samples were investigated using VSM analysis, revealing an increase in M max from 3.98 × 10−3 to 10.40 × 10−3 emu/g. This enhancement was associated with the activation of the FCE, induced by the presence of oxygen vacancies. These findings are instrumental in propelling the advancement of sophisticated materials for both sustainable wastewater treatment and applications in spintronics. [ABSTRACT FROM AUTHOR]

Tellurium dioxide-based quaternary glass system 60TeO 2 –15B 2 O 3 -(25-x) Bi 2 O 3 -xZnCl 2 (0 ≤ x ≤ 20, in the step of 5 mol%) was synthesized by melt quenching technique. The XRD analysis was utilized to confirm that the glass samples were amorphous. The resultant values of molar volume, density, oxygen packing density, and glass transition temperature were shown to decrease with rise in ZnCl 2 content. By employing vibrational spectroscopy, TeO 2 endures as structural units trigonal pyramidal TeO 3 , TeO 3+1 , trigonal bipyramidal TeO 4 , together with TeO 6 polyhedral. The optical characterization of the current glass system shows the presence of indirect transitions with optical band gap range from 2.16 eV to 3.02 eV. Along with the rise in ZnCl 2 content, the Urbach energy value shows a tendency towards lowering values (0.436 eV–0.203 eV), which denotes a reduction in defect concentration. Metallization criterion values fall between 0.329 and 0.389 indicates that the current glass system can be utilizes for non-linear applications. FTIR Spectra and Optical absorbance spectra of 60TeO 2 – 15B 2 O 3 - (25-x) Bi 2 O3- xZnCl 2 of glass system. [Display omitted] • Glass transition temperature decreases with an increase in ZnCl 2 content. • FTIR and Raman result shows that TeO 4 units transform into TeO 3 units and NBO increases with decrease in Bi 2 O 3 content. • Optical band gap increases with the rise in ZnCl 2 content. • Prepared glass system can be utilized for non-linear optical applications. [ABSTRACT FROM AUTHOR]

The significance of self-peptide-MHC-I/TCR (SMT) interaction in the survival of CD8+ T cells during naïve- and developmental-stages is well documented. However, the same for the memory stage is contentious. Previous studies have attempted to address the issue using MHC-I or TCR deficient systems, but inconsistent findings with memory CD8+ T cells of different TCR specificities have complicated the interpretation. Differential presence and/or processing of TCR-signals downstream in memory CD8+ T cells of different TCR specificities could be thought of as a reason. In this study, we examined the TCR-signals downstream in memory CD8+ T cells and compared them to the presence of survival-related signals (Annexin-V, Bcl-2, and Ki-67). We categorically tracked foreign antigen-experienced memory CD8+ T (TM) cells generated after Plasmodium pre-erythrocytic-stage malaria infection in C57BL/6 mice. Interestingly, we found that memory CD8+ T cells had more TCR-signals downstream than naive cells. We reasoned and attributed the increased expression of cell adhesion molecules to the enhanced TCR-signaling. TCR-signals downstream correlate more closely with survival signals in naive CD8+ T cells than with death signals in TM cells. Further investigation using antigen-specific CD8+ T cells and diverse infection systems would aid in conceptualizing the findings. [ABSTRACT FROM AUTHOR]