Study of Thermally Activated Phase-Slip and Scaling of Magneto-Resistance Near TC in YBa2Cu3O7−δ/Ag bulk composites

Journal of Superconductivity and Novel Magnetism - Dissipation in YBCO polycrystalline bulk samples added with nominally different amounts of silver (0, 5, 15, 25 wt%) has been studied through...     

Study of crystal structure,dielectric, magnetic and magnetoelecrtic properties of xCoFe2O4-(1-x)Na0.5Bi0.5TiO3 composites

Multiferroic composites of spinel ferrite and ferroelectric xCoFe₂O₄ – (1-x)Na_0.5Bi_0.5TiO₃ (with x = 0.10,0.30,0.50) were efficiently prepared by standard solid state reaction mechanism. X-ray diffractometer was used to analyze crystal structure of the prepared composites. The observed XRD patterns of the composites comprise peaks of both the phases i.e. ferrite and ferroelectric, with no sign of secondary peaks. Rietveld refinement of XRD data further confirms the coexistence of these two phases with cubic (Fd3m) and rhombohedral (R3c) symmetry corresponding to ferrite and ferroelectric phase respectively. The 3-dimensional overview of crystal structure of pure CoFe₂O₄ and Na_0.5Bi_0.5TiO₃ and of composite 0.50CoFe₂O₄?0.50Na_0.5Bi_0.5TiO₃ is generated by using refined parameters. The dielectric constant (ε´) and dielectric loss (tanδ) values were recorded as a function of frequency ranging from 100?Hz to 7?MHz and at different temperatures. Both ε´ and tanδ follow dispersion pattern at lower frequencies while show frequency independent behavior at higher frequencies. The magnetic evaluation carried by analyzing M-H hysteresis loop reveals the ferrimagnetic characteristics of these composites. The highest value of magnetic moment is 1.12μ_B observed for composite 0.50CoFe₂O₄ – 0.50Na_0.5Bi_0.5TiO_3. Magnetoelectric (ME) voltage coefficient (α) was also demonstrated to observe the interaction between ferrite and ferroelectric phases. The highest value of α (72.72μV/Oe cm) is obtained for low ferrite composition 0.10CoFe₂O₄ – 0.90Na_0.5Bi_0.5TiO₃, which suggests the dependence of magnetoelectric response on the resistivity of the composites.     

Cost of extracorporeal life support in pediatric patients with acute respiratory failure

OBJECTIVES: To determine the impact of extracorporeal life support (ECLS) on mortality in pediatric patients with acute hypoxemic respiratory failure (AHRF) at our institution; and to calculate the hospital charges associated with the use of ECLS. DESIGN: Retrospective review of medical records and hospital charges. SETTING: Pediatric intensive care unit (ICU) of a university-affiliated children's hospital. PATIENTS: Twenty patients admitted to the pediatric ICU between 1991 and 1995 for AHRF who received ECLS as a part of their hospital course. INTERVENTIONS: Predicted mortality was calculated using the Pediatric Respiratory Failure score and was compared with survival at the time of hospital discharge. Hospital charges were used as a proxy for resource utilization. Cost-per-life-year-saved calculations were performed based on a normal life expectancy for survivors. MEASUREMENTS AND MAIN RESULTS: Twenty patients were identified. The median age was 4.83 yrs. The median duration of ECLS was 9 days, with 19.5 days in the pediatric ICU and 23.5 days for the entire hospital length of stay. The observed mortality rate for these patients was 20%. Median predicted mortality rate based on the Pediatric Respiratory Failure score calculation was 83%. The hospital charges incurred by these patients was a median of $199,096. Based on a normal life expectancy for survivors, this results in a cost of $4,190/life-year. CONCLUSIONS: ECLS for the pediatric patient with AHRF is done at a considerable cost. However, ECLS affects survival favorably, and compares favorably when considering cost/life-year calculations. The data presented in this study may serve as a benchmark for comparison with newer therapies (i.e., liquid ventilation, nitric oxide). These data also provide a framework for cost-based analyses at other ECLS institutions.     

Performance Evaluation of SFBC MIMO–OFDM Using FrFT Under TWDP Fading Channel

Wireless Personal Communications - Multiple-input–multiple-output orthogonal frequency division multiplexing (MIMO–OFDM) is a promising 4G technology to increase data rate and capacity...     

Engineered perovskite LaCoO3/rGO nanocomposites for asymmetrical electrochemical supercapacitor application

Journal of Materials Science: Materials in Electronics - Here, we report the synthesis route of LaCoO3 and nanocomposite with reduced graphene oxide (rGO) via solvothermal approach. The study of...     

Mutual Insight on Ferroelectrics and Hybrid Halide Perovskites: A Platform for Future Multifunctional Energy Conversion

An insight into the analogies, state‐of‐the‐art technologies, concepts, and prospects under the umbrella of perovskite materials (both inorganic–organic hybrid halide perovskites and ferroelectric perovskites) for future multifunctional energy conversion and storage devices is provided. Often, these are considered entirely different branches of research; however, considering them simultaneously and holistically can provide several new opportunities. Recent advancements have highlighted the potential of hybrid perovskites for high‐efficiency solar cells. The intrinsic polar properties of these materials, including the potential for ferroelectricity, provide additional possibilities for simultaneously exploiting several energy conversion mechanisms such as the piezoelectric, pyroelectric, and thermoelectric effect and electrical energy storage. The presence of these phenomena can support the performance of perovskite solar cells. The energy conversion using these effects (piezo‐, pyro‐, and thermoelectric effect) can also be enhanced by a change in the light intensity. Thus, there lies a range of possibilities for tuning the structural, electronic, optical, and magnetic properties of perovskites to simultaneously harvest energy using more than one mechanism to realize an improved efficiency. This requires a basic understanding of concepts, mechanisms, corresponding material properties, and the underlying physics involved with these effects.     

Co-extrusion Encapsulation of Probiotic Lactobacillus acidophilus Alone or Together with Apple Skin Polyphenols: An Aqueous and Value-Added Delivery System Using Alginate

This study presents one novel aqueous delivery system that was produced by co-extrusion technology using 1 % and 0.5 % alginate solutions as the shell wall and the core medium, respectively, to encapsulate probiotic bacteria (PB) Lactobacillus acidophilus alone or in combination with a value-added apple skin polyphenol extract (ASPE). The survival of PB was evaluated in a model milk drink at 4 °C for 50 days and under acidic conditions (in acidic water at pH 2 and 37 °C for 120 min). Two types of ASPE were prepared using an ethanolic or aqueous method and subjected to analyses of total extracted polyphenol content (TEPC), total antioxidant activity (TAA), vitamin C content, uronic acid (UA) content and polyphenol (PP) composition. The microencapsulation efficiency for all the obtained alginate beads was >96 %, with the beads in roughly spherical shape and with smooth and intact surfaces. The PB co-encapsulated with an ASPE had significantly (P?<?0.05) greater viability in milk than the unencapsulated PB in milk. After 50 days of storage at 4 °C in milk, the cell loss was only 0.13 and 0.16 log CFU (colony forming units)/mL milk for the PB co-encapsulated with the aqueous or ethanolic ASPE, respectively, compared with 1.1 log CFU/mL milk for the unencapsulated PB and 0.34 log CFU/mL milk for the PB encapsulated without ASPE. The co-encapsulation of PB with an aqueous or ethanolic ASPE also greatly protected PB against the current strong acidic condition with cell loss 2.61 and 2.78 log CFU/g fresh bead, respectively. A much lower cell loss was detected for the PB encapsulated alone (3.08 log CFU/g fresh bead) than for the unencapsulated PB (5.41 log CFU/g fresh bead). The differences between the aqueous and ethanolic ASPE in TAA and bioactive contents apparently caused the difference in PB viability in milk or the current acidic system, which potentially leads to a slightly varied nutritional value of the final encapsulated products. It is feasible and beneficial to use apple skin (a fruit waste) as a bioactive ingredient (containing polyphenols, pectin and vitamin C) to preserve the viability of PB via encapsulation technology. The selection of an aqueous or ethanolic ASPE ultimately depends on the required bioactive composition and PB viability of the final encapsulated product.     

Score-based Incentive Mechanism (SIM) for live multimedia streaming in peer-to-peer network

A decentralized model is primarily used for communication and file transfer, the peer-to-peer network is based on this model. The field of real-time communication and media streaming has witnessed enormous growth in recent times owing to their use of peer-to-peer network. A significant part of Internet traffic is being created by the peer-to-peer network resulting in an increase in its demand. The rise in prominence of peer-to-peer network can be attributed to its properties like resource utilization and distributed nature. Resource utilization of peer-to-peer network is one foremost motive for selecting this network over the traditional client-server architecture. The availability of selfish peer or free riders affects the total resource utilization and degrades the performance of the network. So, there is a requirement of an incentive-based mechanism to motivate the selfish peer or free riders in the network to improve the performance of the network. In this paper, we will discuss a new score based incentive mechanism to improve the overall resource utilization. This approach is based on a reward-punishment based method, so the peers are encouraged or motivated to share more resources and chastise selfish peers. For calculating the score value of a peer, parameters like upload capacity, video quality, control packets, a time period for which peers stay in the network can be used. Different score values are assigned for different parameters. The simulation results presented in this paper verify the approach and illustrate that the quality of video and performance of network improves using our new score based incentive mechanism. The parameters used for calculating the performances are; end-to-end delay, playback delay, start-up delay, and frame redundancy etc.