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This work investigates the AC conductivity, impedance spectroscopy, and modulus formulation of varied compositions of glass samples within the modified borovanadate glassy system, synthesized using the melt-quenching technique. Up to 10 mol% of BaO, the AC conductivity shows a rising trend as BaO content rises; however, for x = 15&20 mol%, there is a drop. The Almond West model fits the experimental data of ac conductivity and parameters such as crossover frequency, frequency exponent (s), and direct current conductivity are retrieved. All samples feature a CBH conduction mechanism at varying frequencies, except for VBa1, which has a small polaron quantum mechanical mechanism. There is good agreement in the activation energy derived from conductivity (0.565–0.742 eV), electric modulus (0.526–0.616 eV), and impedance research (0.530–0.743 eV). Dielectric studies reveal non-Debye-type behavior. According to impedance formalism, electric conduction occurs through Ba2+ ions and electron/polarons. This characteristic renders the glasses well-suited for energy storage devices. [ABSTRACT FROM AUTHOR]

The quaternary glass system 60TeO2-(25−x)Bi2O3-15B2O3-xKCl has been prepared by the melt-quenching process with x ranging from 0 to 20 mol%. X-ray diffraction patterns confirmed the amorphous nature of the synthesized glasses, showing no sharp crystalline peaks. The techniques field emission scanning electron microscopy and energy dispersive X-ray spectroscopy provide information about the surface morphology and elemental composition of the synthesized glass system, respectively. Physical parameters such as density, molar volume, ion concentration, interionic distance, polaron radius, and cation field strength were calculated to determine structural stability. Density and molar volume both decrease with an increase in KCl content. Oxygen packing density decreases with increasing KCl concentration, indicating a rise in non-bridging oxygen atoms. Using differential scanning calorimetry, the glass transition temperature (Tg) was calculated. Its value is found to decrease as the KCl content increases. FTIR and Raman spectra indicate the transformation of TeO4 units into TeO3 units and BO4 units into BO3 units with an increase in KCl content. The diffuse reflectance spectra method is used to study optical parameters such as optical band gap, cut-off wavelength, Urbach energy, refractive index, and metallization criteria. The optical indirect band gap energies (Eopt) range from 2.78 to 3.31 eV and are calculated by applying Tauc's relation. On the other hand, the values of the urbach energy (EU) vary from 0.289 to 0.183 eV, indicating disorderliness or defects in the glass samples decrease with increasing KCl content. The synthesized glasses can be considered for non-linear optical applications since their metallization criterion (M) values ranged from 0.373 to 0.407. The dielectric parameters of the glasses were calculated on a frequency scale of 10–1 to 106 Hz by varying the temperature from 453 to 553 K. Dielectric analysis of the as-prepared glasses shows the non-Debye type behavior. [ABSTRACT FROM AUTHOR]

Introduction: Staphylococcus aureus bacteremia (SAB) is a life-threatening infection particularly involving methicillin-resistant S. aureus (MRSA). In contrast to resolving MRSA bacteremia (RB), persistent MRSA bacteremia (PB) blood cultures remain positive despite appropriate antibiotic treatment. Host immune responses distinguishing PB vs. RB outcomes are poorly understood. Here, integrated transcriptomic, IL-10 cytokine levels, and genomic analyses sought to identify signatures differentiating PB vs. RB outcomes. Methods: Whole-blood transcriptomes of propensity-matched PB (n=28) versus RB (n=30) patients treated with vancomycin were compared in one independent training patient cohort. Gene expression (GE) modules were analyzed and prioritized relative to host IL-10 cytokine levels and DNA methyltransferase-3A (DNMT3A) genotype. Results: Differential expression of T and B lymphocyte gene expression early in MRSA bacteremia discriminated RB from PB outcomes. Significant increases in effector T and B cell signaling pathways correlated with RB, lower IL-10 cytokine levels and DNMT3A heterozygous A/C genotype. Importantly, a second PB and RB patient cohort analyzed in a masked manner demonstrated high predictive accuracy of differential signatures. Discussion: Collectively, the present findings indicate that human PB involves dysregulated immunity characterized by impaired T and B cell responses associated with excessive IL-10 expression in context of the DNMT3A A/A genotype. These findings reveal distinct immunologic programs in PB vs. RB outcomes, enable future studies to define mechanisms by which host and/or pathogen drive differential signatures and may accelerate prediction of PB outcomes. Such prognostic assessment of host risk could significantly enhance early anti-infective interventions to avert PB and improve patient outcomes. [ABSTRACT FROM AUTHOR]

In the present study, lead-modified bismuth borovanadate glasses were synthesized using the conventional melt-quench technique, maintaining a fixed composition of (50 − x)V2O5–40B2O3–10Bi2O3–xPbO, where x ranged from 5 to 25 mol% in 5 mol% increments. To confirm the amorphous nature of the samples, X-ray diffraction was utilized. Several physical properties, including density (ρg) (3.55 to 4.41 g/cm3), molar volume (Vm) (47.21 to 39.83 cm3/mol), crystalline volume (Vc) (42.09 to 35.94 cm3/mol), and oxygen packing density (OPD) (80.49 to 75.32 g-atom/l), were examined and found to exhibit composition-dependent variations. Additionally, various other parameters were determined, including interionic distance (Ri) (1.16 to 0.65 cm−1), lead yield field (F) (0.38 to 1.21 cm−2), concentrations of Pb2+ ions (N) (ranging from 0.64 to 3.78 ions/cm3), and Polaron radius (Rp) (ranging from 4.68 to 2.60 cm−1). The analysis of DSC thermograms revealed a positive correlation between the concentration of lead oxide and the glass transition temperature (Tg), which varied from 254 to 295 ºC. This suggests an improvement in the thermal stability of the glass system with increasing lead oxide content. Structural investigations using infrared and Raman spectroscopy indicated that V2O5 served a dual role as a network former (with VO5 units) and as a modifier (with VO4 units). The presence of PbO and Bi2O3 as modifiers facilitated the transformation of BO3 units into BO4 units and the formation of diborovanadate ([B2V2O9]2−) groups and strong B–O–V linkages. The optical energy band gap (Eopt), determined through UV–visible spectroscopy, showed a consistent increase with the progressive incorporation of PbO. Both direct allowed (1.986 to 2.392 eV) and indirect allowed (1.582 to 2.087 eV) band gaps exhibited this rising trend. Furthermore, the prepared glasses demonstrated a high level of optical basicity (1.182 to 1.168), electronic polarizability (3.419 to 3.327) of oxide ions, third-order non-linear optical susceptibility (0.141 to 0.063 × 10–10 esu), and metallization criterion (0.281 to 0.323). These results suggest that the glasses prepared in this study have the potential for use in non-linear optical applications. [ABSTRACT FROM AUTHOR]

The goal of the current work is to identify the structural, magnetic, and optical properties of Gd-doped SnO2 nanoparticles and their potential use in the treatment of water contaminated with dye. These Gd-doped SnO2 (Gd = 0%, 0.5%, 1.5%, 3%, 5%) samples were prepared by the cost-effective sol–gel approach. XRD & FTIR were used to study structural properties and to confirm that the synthesized samples have single-phase crystalline nature. Using XRD Crystallite size have been calculated and found to be in the range 12.14–9.60 nm. Particle size obtained from HRTEM lying in the range 15.94–9.86 nm which was in well agreement with XRD. Raman, PL and XPS spectroscopy were utilized to investigate defects/oxygen vacancies in the lattice. Magnetic investigations indicate that the magnetic character of synthesized samples with maximum magnetization3.95 × 10–3 emu/g for Gd 5%. UV-DRS further showed that the band gap was reduced up to 5% Gd (Eg = 3.68 eV) in comparison to pure SnO2 (Eg = 3.81 eV) due to the formation of vacancy defects. In comparison to pure SnO2, Gd-doped SnO2 (Gd 5%) was found to have a maximum photodegradation efficiency of 95.64% in 60 min under UV irradiation for Rose Bengal dye. Henceforth, it can be concluded that SnO2 is a remarkable multifunctional material having uses in spintronic devices and as a catalyst in the degradation of organic dyes because of the improvement in the ferromagnetic character and enhancement in catalytic behavior on incorporation of rare-earth ions. [ABSTRACT FROM AUTHOR]

Modified and synthetic α‐amino acids are known to show diverse applications. Histidine, which possesses numerous applications when subjected to synthetic modifications, is one such amino acid. The utility of modified histidines varies widely from remarkable biological activities to catalysis, and from nanotechnology to polymer chemistry. This renders histidine residue an important place in scientific research. Histidine is a well‐studied scaffold and constitutes the active site of various enzymes catalyzing important reactions in the biological systems. A rational modification in histidine structure with a distinctly developed protocol extensively changes its physical and chemical properties. The utilization of modified histidines in search of potent, target selective and proteostable scaffolds is vital in the development of bioactive peptides with enhanced drug‐likeliness. This review is a compilation and analysis of reported side‐chain ring modifications at histidine followed by applications of ring‐modified histidines in the synthesis of various categories of bioactive peptides and peptidomimetics. [ABSTRACT FROM AUTHOR]

Box‐Behnken design was applied for the development of a novel, precise, simple, and accurate high‐performance thin‐layer chromatography method for simultaneous estimation of mentioned drugs in the formulation. Optimization was performed using Quality by Design. Principles of risk assessment followed by application of design for optimization of chromatographic conditions to determine critical parameters: volume of hexane, chamber saturation time, solvent front and their effects on critical method attributes: Rf values of both drugs. Optimized conditions were determined through Derringer's desirability approach of the multi‐criteria decision‐making technique. Good resolution using optimized mobile phase, hexane:ethyl acetate:ammonium acetate in methanol (5.1:3:2) with Rf values 0.34 and 0.67 for Ivabradine Hydrochloride and Carvedilol, respectively, was obtained. The method was validated as per International Council on Harmonization having a linear range of 1000–5000 ng/band of Ivabradine and 1250–6250 ng/band for Carvedilol, respectively. %Recovery was in range of 99.23–101.3 and 99.8–100.5, respectively. Precision and robustness were found to be in an acceptable range. Thus, Quality by Design based method development assisted in making design space with knowledge of all method performance characteristics with a better understanding of high‐performance thin‐layer chromatography. The Analytical GREEnness profile was assessed using AGREE tool with an overall reliable score of 0.68. [ABSTRACT FROM AUTHOR]

Background: Cytomegalovirus (CMV) infection, either de novo or as reactivation after allotransplantation and chronic immunosuppression, is recognized to cause detrimental alloimmune effects, inclusive of higher susceptibility to graft rejection and substantive impact on chronic graft injury and reduced transplant survival. To obtain further insights into the evolution and pathogenesis of CMV infection in an immunocompromised host we evaluated changes in the circulating host proteome serially, before and after transplantation, and during and after CMV DNA replication (DNAemia), as measured by quantitative polymerase chain reaction (QPCR). Methods: LC-MS-based proteomics was conducted on 168 serially banked plasma samples, from 62 propensity score-matched kidney transplant recipients. Patients were stratified by CMV replication status into 31 with CMV DNAemia and 31 without CMV DNAemia. Patients had blood samples drawn at protocol times of 3- and 12-months post-transplant. Additionally, blood samples were also drawn before and 1 week and 1 month after detection of CMV DNAemia. Plasma proteins were analyzed using an LCMS 8060 triple quadrupole mass spectrometer. Further, public transcriptomic data on time matched PBMCs samples from the same patients was utilized to evaluate integrative pathways. Data analysis was conducted using R and Limma. Results: Samples were segregated based on their proteomic profiles with respect to their CMV Dnaemia status. A subset of 17 plasma proteins was observed to predict the onset of CMV at 3 months post-transplant enriching platelet degranulation (FDR, 4.83E-06), acute inflammatory response (FDR, 0.0018), blood coagulation (FDR, 0.0018) pathways. An increase in many immune complex proteins were observed at CMV infection. Prior to DNAemia the plasma proteome showed changes in the anti-inflammatory adipokine vaspin (SERPINA12), copper binding protein ceruloplasmin (CP), complement activation (FDR = 0.03), and proteins enriched in the humoral (FDR = 0.01) and innate immune responses (FDR = 0.01). Conclusion: Plasma proteomic and transcriptional perturbations impacting humoral and innate immune pathways are observed during CMV infection and provide biomarkers for CMV disease prediction and resolution. Further studies to understand the clinical impact of these pathways can help in the formulation of different types and duration of anti-viral therapies for the management of CMV infection in the immunocompromised host. [ABSTRACT FROM AUTHOR]

Radiation attenuated sporozoite (RAS), a whole‐parasite vaccine approach, provides sterile protection against malaria. However, RAS immunization does not confer protection for long, and that has been correlated with the waning parasite–induced memory CD8+ T‐cell responses. Interestingly, an intermittent infectious (wild type) sporozoite challenge to the RAS‐vaccinated mice lengthened the protection period from 6 to 18 months. Herein, we have studied the changes induced by the infectious sporozoites in RAS‐induced memory CD8+ T cells for conferring lengthened protection. We observed that the infectious sporozoite challenge boosted the frequency of foreign antigen–experienced memory CD8+ T cells. In those CD8+ T cells, it has reduced the Annexin‐V reactivity, raised Bcl‐2 expression, and also more cells undergo homeostatic proliferation (Ki‐67+). It has also scaled down the frequency of Nur77 and CX3CR1 high expressing cells in those memory CD8+ T‐cell populations which we further correlated with better survival signals. [ABSTRACT FROM AUTHOR]

Immunization with radiation-attenuated sporozoites (RAS) shown to confer complete sterile protection against Plasmodia liver-stage (LS) infection that lasts about 6 to 9 months in mice. We have found that the intermittent infectious sporozoite challenge to immune mice following RAS vaccination extends the longevity of sterile protection by maintaining CD8+ T cell memory responses to LS infection. It is reported that CD8α+ dendritic cells (DCs) are involved in the induction of LS-specific CD8+ T cells following RAS or genetically attenuated parasite (GAP) vaccination. In this study, we demonstrate that CD8α+ DCs respond differently to infectious sporozoite or RAS inoculation. The higher accumulation and activation of CD8α+ DCs was seen in the liver in response to infectious sporozoite 72 h postinoculation and found to be associated with higher expression of chemokines (CCL-20 and CCL-21) and type I interferon response via toll-like receptor signaling in liver. Moreover, the infectious sporozoites were found to induce qualitative changes in terms of the increased MHCII expression as well as costimulatory molecules including CD40 on the CD8α+ DCs compared to RAS inoculation. We have also found that infectious sporozoite challenge increased CD40L-expressing CD4+ T cells, which could help CD8+ T cells in the liver through "licensing" of the antigen-presenting cells. Our results suggest that infectious sporozoite challenge to prior RAS immunized mice modulates the CD8α+ DCs, which might be shaping the fate of memory CD8+ T cells against Plasmodium LS infection. [ABSTRACT FROM AUTHOR]

A two-dimensional steady-state model of a catalytic plate reactor for diesel steam reforming is developed. Heat is provided indirectly to endothermic reforming sites by flue gas from a SOFC tail-gas burner. Two experimentally validated kinetic models on diesel reforming on platinum (Pt) catalyst were implemented for a comparative study; the model of Parmar et al., Fuel. 2010;89(6):1212-1220 for a Pt/Al2O3 and the model of Shi et al., International Journal of Hydrogen Energy. 2009;34(18):7666-7675 for a Pt/Gd-CeO2 (GDC). The kinetic models were compared for: species concentration, approach to equilibrium, gas hourly space velocity and effectiveness factor. Cocurrent flow arrangement between the reforming and the flue gas channels showed better heat transfer compared to counter-current flow arrangement. The comparison between the two kinetic models showed that different supports play significant role in the final design of a reactor. The study also determined that initial 20% of the plate reactor has high diffusion limitation suggesting to use graded catalyst to optimize the plate reactor performance. © 2016 American Institute of Chemical Engineers AIChE J, 63: 1102-1113, 2017 [ABSTRACT FROM AUTHOR]

The optical characterization of glass samples in the system 40SiO2 · xZnO · (60-x)Bi2O3 with x=0, 5, 10, 15, 20, 25, 30, 35, and 40 prepared by conventional melt-quench technique has been carried out in the light of Hydrogenic Excitonic Model (HEM). The absorption coefficient spectra show good agreement with theoretical HEM for the present glass system and the values of different parameters like Eg, R, Γ1, Γc, and Co have been estimated from fitting of this model. The values of energy band gap estimated from fitting of HEM with experimental data are in good agreement with those obtained from Tauc’s plot for direct transitions. The band gap energy is found to increase with increase of ZnO content. The decrease in values of Urbach energy with increase in ZnO content indicates a decrease in defect concentration in the glass matrix on addition of ZnO content. Optical constants n and k obey k-k consistency and the dielectric response of the studied glass system is similar to that obtained for Classical Electron Theory of Dielectric Materials. The calculated values of the metallization criterion (M) show that the synthesized glasses may be good candidates for new nonlinear optical materials. [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]