Lysozyme as a barrier to growth of Bacillus anthracis strain Sterne in liquid egg white, milk and beef

In this study, we investigated the role of lysozyme on the viability of Bacillus cereus, Bacillus subtilis, Bacillus pumilus and Bacillus anthracis (Sterne) in egg white (EW), ground beef and milk. At 35 °C in EW, growth rates (GR) for B. cereus, B. subtilis, B. pumilus and B. anthracis were 0.005, −0.018, −0.028 and −0.029 OD₆₀₀/h, respectively. Heat-treating EW at 55 and 60 °C reduced the inactivating effect of EW by 3.1 and 10.5-fold, respectively. Addition of lysozyme (2 mg/ml) to 60 °C-treated EW increased the inactivation rate 5.76-fold, indicating involvement of lysozyme in B. anthracis inactivation. B. anthracis inactivation was influenced by pH, as shown by a progressive increase in inactivation rate from 0.25 to −4.42 logs CFU/h over a pH range of 6.0-8.5. Adding 2 mg/ml lysozyme to milk and ground beef also suppressed the growth of B. anthracis 3.3 and 6.5-fold, respectively. These data indicate that lysozyme, as a natural component of EW or potential additive in other foods, could reduce biothreat risks presented by bioterror agents.     

Hydrogen peroxide sensors for cellular imaging based on horse radish peroxidase reconstituted on polymer-functionalized TiO₂ nanorods

We describe the reconstitution of apo-horse radish peroxidase (apo-HRP) onto TiO(2) nanorods functionalized with a multifunctional polymer. After functionalization, the horse radish peroxidase (HRP) functionalized TiO(2) nanorods were well dispersible in aqueous solution, catalytically active and biocompatible, and they could be used to quantify and image H(2)O(2) which is a harmful secondary product of cellular metabolism. The shape, size and structure of TiO(2) nanorods (anatase) were analyzed by transmission electron microscopy (TEM), high resolution TEM (HRTEM), electron diffraction (ED) and X-ray diffraction (XRD). The surface functionalization, HRP reconstitution and catalytic activity were confirmed by UV-Vis, FT-IR, CLSM and atomic force microscopy (AFM). Biocompatibility and cellular internalization of active HRP reconstituted TiO(2) nanorods were confirmed by a classical MTT cytotoxicity assay and confocal laser scanning microscopy (CLSM) imaging, respectively. The intracellular localization allowed H(2)O(2) detection, imaging and quantification in HeLa cells. The polymer functionalized hybrid system creates a complete sensor including a "cell positioning system" in each single particle. The flexible synthetic concept with functionalization by post-polymerization modification allows introduction of various dyes for sensitisation at different wavelengths and introduction of various anchor groups for anchoring on different particles.     

Removal of direct Red‐31 and direct Orange‐26 by low cost rice husk: Influence of immobilisation and pretreatments

The aim of the present study is to investigate the influence of free, carboxymethyl cellulose (CMC) immobilised, PVA–alginate immobilised, and HCl treated rice husk on the removal of Direct Red‐31 and Direct Orange‐26 dyes. The biosorption capacity of the rice husk increased with HCl treatment (67.39 and 45.34 mg/g) and decreased with PVA–alginate immobilisation (9.73 and 10.03 mg/g) as compared to the free biomass (65.56 and 45.58 mg/g) at 200 mg/L dye concentration for Direct Red‐31 and Direct Orange‐26, respectively. Equilibrium data were best described by Langmuir Type 1 for Direct Red‐31 and Direct Orange‐26 (free, CMC immobilised, PVA–alginate immobilised, and HCl treated). Best correlation coefficients for Direct Red‐31 and Direct Orange‐26 using free, CMC immobilised, PVA–alginate immobilised, and HCl treated rice husk were obtained for pseudo‐second order and Elovich kinetic models. Values of Gibbs free energy (ΔG°) and enthalpy change (ΔH°) indicated that reaction was spontaneous and endothermic in nature at the studied temperatures. FT‐IR studies showed the involvement of carbonyl, carboxyl, and amide groups in the biosorption process. SEM exhibited the morphological changes on the biosorbent surface and BET analysis to determine the surface area is also carried out.     

Melanoma localization and classification through faster region-based convolutional neural network and SVM

Multimedia Tools and Applications - Melanoma is a lethal skin cancer disease affecting millions of people around the globe and has a high mortality rate. Dermatologists perform the manual...     

Mimicking peroxidase active site microenvironment by functionalized graphene quantum dots

The development of high-efficiency peroxidase mimetics is highly desirable in view of high cost and low stability of natural enzymes. From the perspective of mimicking active site microenvironment at low cost, we herein report a novel histidine-functionalized graphene quantum dot (His-GQD)/hemin complex, which exhibits the highest catalytic rate for the peroxidase-based chromogenic reaction among the hemin-containing mimetics reported so far. Also, our peroxidase mimetic shows excellent tolerance to strongly acidic conditions and can function in a wide temperature range. Lineweaver-Burk plots and comprehensive electron paramagnetic resonance analysis reveal a ping-pong type catalytic mechanism for this mimetic. In addition, His-GQD/hemin demonstrates high efficiency and accuracy in detecting H₂O₂ and blood glucose. Our work provides an effective design of artificial enzymes for practical applications.

     

Performance relevant to the thermophysiological wear comfort of hip protective garments,Part I: clothing area factor of hip protective garments in clothing ensembles

The clothing area factors of several hip protective garments, alone and in ensembles, were studied in this research (Part I). Two methods were used to determine the clothing factor area: the standard photography method, and a newly developed method involving 3D scanning. The results from the two methods were consistent; therefore, either method can be used to determine clothing area factors, depending on the available equipment. The methods can be used to determine the thermal insulation performance of hip protective garments and garments in ensembles, as covered in Part II of the study.     

Influence of Chemical Reaction on Heat and Mass Transfer in MHD Radiative Flow due to Non-Coaxial Rotations of Disk and Fluid at Infinity

Theoretical Foundations of Chemical Engineering - An exact solution of the problem regarding influence of chemical reaction and buoyant force on the heat and mass transfer in a radiative flow due...     

Structure-Preserving Dynamics of Stochastic Epidemic Model with the Saturated Incidence Rate

The structure-preserving features of the nonlinear stochastic models are positivity, dynamical consistency and boundedness. These features have a significant role in different fields of computational biology and many more. Unfortunately, the existing stochastic approaches in literature do not restore aforesaid structure-preserving features, particularly for the stochastic models. Therefore, these gaps should be occupied up in literature, by constructing the structure-preserving features preserving numerical approach. This writing aims to describe the structure-preserving dynamics of the stochastic model. We have analysed the effect of reproduction number in stochastic modelling the same as described in the literature for deterministic modelling. The usual explicit stochastic numerical approaches are time-dependent. We have developed the implicitly driven explicit approach for the stochastic epidemic model. We have proved that the newly developed approach is preserving the structural, dynamical properties as positivity, boundedness and dynamical consistency. Finally, convergence analysis of a newly developed approach and graphically illustration is also presented.