The effect of freezing and thawing on the magnetic resonance imaging parameters of water in beef, lamb and pork meat

A new multisample magnetic resonance imaging (MRI) technique has been used to measure the values of T ₁, T ₂, magnetization transfer (MT) rate and liquid proton density ratio ( M ₀%) for water in fresh and frozen–thawed beef, lamb and pork; four samples from the longissimus dorsi muscle of 25 different individuals per species were studied. The effect of two different chilling regimes, standard and tenderloin, were also studied. Standard chilled pork and lamb had a significantly higher M ₀% than tenderloin chilled samples, but there was no correlation between M ₀% and fresh weight; the differences in M ₀% are thought to be due to differences in MR (magnetic resonance)-visible water. There was a significant decrease in water content, T ₁ relaxation time, and a significant increase in MT rate in the frozen–thawed samples when all the data were pooled for each species. However, individual animals differed in the magnitude and direction of the change; this means that because of interanimal variation, measurements of MR parameters from a single sample of meat cannot be used at present to authenticate it.     

The effect of high pressure treatment on rheological characteristics and colour of mango pulp

The effect of high‐pressure (HP) treatment (100–400 MPa for 15 or 30 min at 20 °C) on the rheological characteristics and colour of fresh and canned mango pulps was evaluated. Differences were observed in the rheological behaviour of fresh and canned mango pulps treated with HP. Shear stress–shear rate data of pulps were well described by the Herschel–Bulkley model. The consistency index (K) of fresh pulp increased with pressure level from 100 to 200 MPa while a steady decrease was noticed for canned pulp. For fresh pulp the flow behaviour index decreased with pressure treatment whereas an increasing trend was observed with canned pulp. Storage and loss moduli of treated fresh pulp with HP increased linearly with angular frequency up to 200 MPa for a treatment time of 30 min while a steady decreasing trend was found for processed pulp. No significant variation in colour was observed during pressure treatment.     

A benign approach for novel synthesis of Eu3+ doped MgNb2O6: Its photoluminescence and photocatalytic studies

The Present work involves the production of Eu³⁺ (1–11 mol %) doped MgNb₂O₆ nanophosphors (NPs) by combustion technique using ODH as a fuel for the first time and well characterized. The average crystallite and the energy gap of the samples were found to be in the range of 20–45 nm and 4.65–5.66 eV respectively, TEM results reflects the same crystallite size values. The effect of doping was confirmed by the characteristic emission peaks recorded at ~535, 590, 614, 642 and 698 nm may be attributed to the 4f–4f intra shell transitions (⁵D₀→⁷F_j=0,1,2,3,4) of Eu³⁺ cations when bombarded at 395 nm energy. Judd–Ofelt parameters (Ω₂, Ω₄), transition probabilities (A_T), quantum efficiency (η), luminescence lifetime (τ_rad) are discussed in detail. From the emission spectra, CIE (Commission International de I’ Eclairage) chromaticity co-ordinates and Correlated color temperature (CCT) were estimated. Langmuir-Hinshelwood model was used to study the photocatalytic degradation of AR-88 dye. The above results confirmed that the present phosphor can be potentially used for display and photocatalytic applications.     

Molecular docking,synthesis, and characterization of chitosan-graft-2-mercaptobenzoic acid derivative as potential drug carrier

Chitosan is a hydrophilic polymer with prominent mucoadhesive properties. However, it forms weak hydrogen bonds with mucin thus limiting its mucoadhesion and exhibit reduced bioavailability due to its short retention time in the body. The aim of the present study was to synthesize and characterize novel thiolated chitosan with improved functional property. A unique approach of using molecular docking to select ligand to chemically modify chitosan has been employed in the present research. A set of ligands were screened virtually using docking analysis and 2-mercapto benzoic acid showed the lowest glide score of −4.31 Kcal/Mol thus displayed better binding interaction with chitosan. Based on the docking results, the best-fit ligand was selected for wet lab synthesis. 2-Mercapto benzoic acid was covalently attached to chitosan via formation of an amide bond and the reaction was mediated by carbodiimide and N-hydroxysuccinimide. The synthesized polymer was in turn evaluated for zeta potential, Fourier transformed infrared, differential scanning calorimetry, molecular weight that confirmed conjugation of chitosan with the thiol ligand. The prepared thiomer was further subjected to mucoadhesion studies and displayed better mucoadhesion properties as compared to unmodified chitosan. Thus, the potential of the novel thiomer can be further explored as an excipient for drug delivery system with an emphasis on mucoadhesion.     

An efficient elite group-based routing protocol for wireless sensor network

ABSTRACT

In recent days, due to the wide verities of applications of Wireless Sensor Networks, it gets recognition from research communities. As the sensor nodes are operated through limited battery capacity, how to utilise the battery power or energy in an optimum way is a major concern. In this paper, we have addressed the energy issue of wireless sensor networks. We have developed an energy-efficient routing protocol. This paper proposes the Novel Elite group concept where the cluster-head selection process is restricted to only a few high-energy nodes rather than all nodes in the network, which substantially reduces the number of cluster-head selection overhead in every iteration, decreases the energy consumption and increases network lifetime. Our method is compared with three well-known routing protocols, i.e. EECRP (Energy Efficient Centroid-Based Routing Protocol) protocol, NCBR (New Cooperative Balancing Routing Protocol) and Mod-LEACH (Modified low-Energy Adaptive Clustering Hierarchy Protocol). We have conducted a simulation in NS-2 simulator. We have computed various network quality parameters like Throughput, transmission delay, analysis of the number of dead nodes (reciprocal of alive nodes) and energy dissipation with respect to the number of simulation rounds. The simulation results show that our proposed methodology outperforms the rest of the protocol.     

Experimental parametric investigation of platinum catalysts using hydrogen fuel

The aviation organization is creating awareness for the overall reduction of NOx emissions by up to 80% in the near future. This motivates to conduct research on the current state of art, catalytic stabilized combustion chamber using hydrogen. This was achieved by performing an experimental parametric investigation of Platinum catalysts in two phases. Firstly, the design of three diverse configurations of mixers and was investigated experimentally and numerically. The chosen mixer was implemented in the parametric study of five different Pt catalysts varying in geometric and material properties. This was executed at unpressurized and NOx emission solely due to the catalytic reaction was examined for varying thermal power and air/fuel ratios. Furthermore, temperatures were recorded. Additionally, CFD simulation was accomplished and compared with the measurement data. The overall least NOx achieved was 7.5  ppm at 5 kW for the metal catalyst. The result of this work proposed suitable catalyst for the development of a combined combustor configuration (including catalyst and combustion chamber) which will be intended for small aircraft engine applications.     

Crystal structure refinement of Bi1−xNdxFeO3 multiferroic by the Rietveld method

The effect of Nd doping on Bi_1?xNd_xFeO₃ (x = 0.0, 0.175, 0.20) multiferroics synthesized by chemical co-precipitation method has been investigated by Rietveld analysis of X-ray powder diffraction (XRD) data. The formations of the single-phase compounds were confirmed by XRD. X-ray diffraction along with the Rietveld-refinement showed a gradual change in crystal structure from rhombohedral to triclinic with increasing Nd doping concentration. The bond distances along with bond angles between atoms for all the compounds were calculated which supports the structural results. Raman spectroscopy also recommends a structural change and is accompanied by the weakening of long-range ferroelectric order with increasing doping concentration (x). The results of Raman spectra for BiFeO₃ (BFO) match well with the earlier reported bulk ceramic and epitaxially grown thin film of BFO. The ferroelectric-paraelectric transition in 20% Nd BFO substituted was explained according to the change of Bi–O covalent bond as a result of decline of stereochemical activity of Bi lone pair electron and is further confirmed through ferroelectric polarization (P–E) hysteresis loop.     

A new room-temperature multiferroic material: Y2FeAlO6

In this paper, we report the finding and basic characterization of a new multiferroic material in the form of the Y₂FeAlO₆ (YFAO) double perovskite with orthorhombic structure. In order to study the structural and multiferroic properties in detail, we prepared the polycrystalline YFeO₃ (YFO) and Y₂FeAlO₆ ceramic samples through traditional high temperature solid-state reaction method. XRD analysis confirmed that these two samples are single-phase and all the peaks in the pattern can be indexed with orthorhombic symmetry of the Pnma space group. Compared to YFO, YFAO is more symmetric, and has a more stable crystalline structure and smaller grain size. The Fe ion in YFO and YFAO are in the mixed oxidation state of Fe²⁺ and Fe³⁺, while the relative amount of Fe²⁺ in YFAO is higher than that of YFO. Al³⁺ with filled 2p orbital and grain refinement may be the main reasons for the greatly enhanced multiferroicity of YFAO. The magnetic properties of YFO and YFAO are mainly dominant antiferromagnetism and weak ferromagnetism, and the exchange bias effect disappears in YFAO. The coexistence of ferroelectricity and ferromagnetic orders at room temperature in YFAO promises new opportunities and improvements in next generation applications for spintronic, information storage, and sensors etc.     

Surfactant tunable hierarchical nanostructures of CdIn2S4 and their photohydrogen production under solar light

The hierarchical nanostructures of CdIn₂S₄ were selectively prepared through hydrothermal process in the presence of different surfactants. Structural study demonstrated existence of cubic spinel structure and micro structural study shown a pretty marigold flower like morphology without any surfactant. The effect of surfactants on the morphology and microstructure of CdIn₂S₄ has been studied by using Polyvinyl pyrrolidone (PVP) and Cetyltrimethyl ammonium bromide (CTAB) as a surfactants. The CdIn₂S₄ bipyramids with length of 0.7-1 μm have been obtained using PVP. Interestingly, the nanopetals (thin and transparent) of CdIn₂S₄ are self assembled into hollow spheres in the presence of CTAB. Considering the importance of these unique nanostructures, the growth mechanism has also been proposed. The optical properties demonstrated the band gap in the range of 2.12-2.29 eV which is well within the visible region. In this contest, photocatalytic activity for hydrogen production using the above nanostructures under visible light was also demonstrated. The prima-fascia observations shows that the bipyramidal CdIn₂S₄ exhibit excellent photocatalytic activity for hydrogen production (3238 μmolh⁻¹) than other nanostructures. Being a nanostructured semiconductor chalcogenide with a good stability will also have potential applications in solar cells and LED.     

Osmotic dehydration assisted impregnation of curcuminoids in coconut slices

Osmotic treatment was explored as a method to infuse curcuminoids in coconut slices. The rate of mass transfer of moisture, solid and curcuminoids with or without application of ultrasound were studied over a range of concentration of osmotic solutions (0-50%). The diffusion coefficient of curcuminoids was 1.64 × 10⁻¹⁰ m²/s, when water was used in place of osmotic solute which was further enhanced by the application of ultrasound to 1.87 × 10⁻¹⁰ m²/s. Increase in the concentration of osmotic solution beyond 25% resulted in reversal in the direction of moisture and solid mass transfer. Ultrasound treatment resulted in higher moisture and solid mass transfer due to the breaking of cell structure as revealed by microstructure examination. HPLC analysis revealed that all the curcuminoids (curcumin, demethoxycurcumin and bisdemethoxycurcumin) were infused into the coconut matrix. The present study concluded that osmotic dehydration is a feasible technology for impregnation of functional ingredients into foods without altering its matrix.