Semiconductor photocatalysis often leads to partial or complete mineralization of organic pollutants. Upon irradiation with UV/visible light, semiconductors catalyze redox reactions in presence of ...air/O
2 and water. Here, the potential of a common semiconductor, ZnO, has been explored as an effective catalyst for the photodegradation of two model dyes: Methylene Blue and Eosin Y. A 16
W lamp was the source of UV-radiation in a batch reactor. The effects of process parameters like, catalyst loading, initial dye concentration, airflow rate, UV-radiation intensity, and pH on the extent of photo degradation have been investigated. Substantial reduction of COD, besides removal of colour, was also achieved. A rate equation for the degradation based on Langmuir–Hinshelwood model has been proposed.
The paper deals with the development of a close form solution to find the stability of flexible symmetric horizontal rigid and tuned flexible rotor mounted on hydrodynamic bearing with squeeze film ...damper system. The correlations are developed analytically to find the static equilibrium position of a rigid and flexible rotor-bearing-damper system and stability threshold of the system about its static equilibrium position under isoviscous conditions. Modified Reynolds equation with short damper approximation is used to derive the forces of hydrodynamic bearing and squeeze film damper using π-film approximation under both laminar and turbulent conditions. A simple iterative method is used to predict the stability threshold. Effects of shaft flexibility, damper support flexibility, damper mass and turbulence on stability are discussed. Deployment of squeeze film damper increases the stability limit of horizontal symmetric tuned flexible rotor-bearing system to nearly two times of its original limit and mass of damper play important role to increase the stability threshold of the system. Stability threshold of rigid system can be increased significantly by increasing the damper mass and stiffness. Insertion of turbulence reduces the limits of stability. Further work has been extended to find Thermo-hydrodynamic analysis of rotor -bearing -damper system by solving the Energy equation with adiabatic boundary conditions simultaneously with Reynolds equation with analytical approach. In case of rigid rotor bearing damper system, Thermo-hydrodynamic analysis overestimates the stability threshold as compared to isoviscous conditions, stability limit of horizontal symmetric tuned flexible rotor-bearing -damper system under estimates in comparison with isoviscous conditions till k⇀=1. Stability threshold of rigid system can be increased significantly by increasing the damper mass and stiffness.
•Analytical solution to find stability of rigid and flexible horizontal rotor mounted on HDB with Squeeze Film Damper (SFD). .•Nonlinear fluid forces of both HDB and SFD is considered with Short Bearing Approximation of pi-film and turbulence effects. .•Role of shaft flexibility, damper mass and turbulence on stability threshold was discussed. .
Traumatic brain injury (TBI) is a leading global cause of death and disability. Here we demonstrate in an experimental mouse model of TBI that mild forms of brain trauma cause severe deficits in ...meningeal lymphatic drainage that begin within hours and last out to at least one month post-injury. To investigate a mechanism underlying impaired lymphatic function in TBI, we examined how increased intracranial pressure (ICP) influences the meningeal lymphatics. We demonstrate that increased ICP can contribute to meningeal lymphatic dysfunction. Moreover, we show that pre-existing lymphatic dysfunction before TBI leads to increased neuroinflammation and negative cognitive outcomes. Finally, we report that rejuvenation of meningeal lymphatic drainage function in aged mice can ameliorate TBI-induced gliosis. These findings provide insights into both the causes and consequences of meningeal lymphatic dysfunction in TBI and suggest that therapeutics targeting the meningeal lymphatic system may offer strategies to treat TBI.
We report on combined measurements of heat and charge transport through a single-electron transistor. The device acts as a heat switch actuated by the voltage applied on the gate. The Wiedemann-Franz ...law for the ratio of heat and charge conductances is found to be systematically violated away from the charge degeneracy points. The observed deviation agrees well with the theoretical expectation. With a large temperature drop between the source and drain, the heat current away from degeneracy deviates from the standard quadratic dependence in the two temperatures.
Aims
The aim of this study is to determine the ability of two bioactive compounds, namely, eugenol and linalool, purified from leaves of Ocimum tenuiflorum for eradication of biofilm produced by ...Pseudomonas aeruginosa.
Methods and Results
The phytoextract of O. tenuiflorum (KT), a common ethno‐botanical plant of India, was purified through high‐performance liquid chromatography and was analysed using ultraviolet (UV) spectroscopy and gas chromatography–mass spectrometry (GC‐MS). Eugenol and linalool were found to be the most active amongst all phytocompounds present in phytoextract and showed a significant reduction in the viability of sessile cells of P. aeruginosa and the minimum revival after withdrawal of phyto‐challenge. They could bring about notable reduction in the protein and carbohydrate content of exopolysaccharide of biofilm. Eugenol and linalool could affect the synthesis of quorum sensing (QS) proteins like LasA and LasB as well as virulence factors such as pyocyanin, and rhamnolipids, which seriously hamper the formation of biofilm. The biofilm framework was extremely affected by the phytocompounds through the reduction of protein and carbohydrate content of extracellular polymeric substance (EPS). Another interesting found out was that they brought about maximum inhibition to the genomic DNA and RNA content. The studies were supported by in silico interaction between eugenol and linalool with the QS proteins. The antibiofilm efficacies of eugenol, linalool and phytoextract (KT) were further confirmed by microscopic studies with scanning electron microscopy (SEM), atomic force microscopy and fluorescence confocal microscopy microscopic studies.
Conclusions
The phytocompounds are proved to be more effective than conventional antibiotics in inhibiting the biofilm forming sessile cells and can be used as a replacement for antibiotic.
Significance and Impact of the Study
Pure eugenol extracted from common basil leaves can be used as a safe substitute for common antibiotic for treatment of chronic infections caused by P. aeruginosa. It will be cost effective, devoid of notable side effects and will not generate antibiotic resistance in host body.
An ab initio based framework for quantitatively assessing the phonon contribution due to magnon-phonon interactions and lattice expansion is developed. The theoretical results for bcc Fe are in very ...good agreement with high-quality phonon frequency measurements. For some phonon branches, the magnon-phonon interaction is an order of magnitude larger than the phonon shift due to lattice expansion, demonstrating the strong impact of magnetic short-range order even significantly above the Curie temperature. The framework closes the previous simulation gap between the ferro- and paramagnetic limits.
The major reason that there is not more wide-spread use of titanium alloys is the high cost. Powder Metallurgy (P/M) represents one cost effective approach to fabrication of titanium components. In ...this paper one Powder Metallurgy technique, Additive Manufacturing (AM) is discussed with the emphasis on the “work horse” titanium alloy Ti-6Al-4V. The various approaches to AM are presented and discussed, followed by some examples of components produced by AM. The microstructures and mechanical properties of Ti-6Al-4V produced by AM are listed and shown to compare very well with cast and wrought product. Finally, the economic advantages to be gained using the AM technique compared to conventionally processed material are presented.
Experiments were carried out to determine the minimum material volume in the gauge section of miniature tensile test specimens required to get mechanical properties data comparable to those from ...standard test specimens. The experimental results were verified and aided by numerical and metallurgical analysis simultaneously. In order to generalize the results, three different materials, having large variation in their mechanical properties, were selected for the study.
We demonstrate gate control of electronic heat flow in a thermally biased single-quantum-dot junction. Electron temperature maps taken in the immediate vicinity of the junction, as a function of the ...gate and bias voltages applied to the device, reveal clearly defined Coulomb diamond patterns that indicate a maximum heat transfer at the charge degeneracy point. The nontrivial bias and gate dependence of this heat valve results from the quantum nature of the dot at the heart of device and its strong coupling to leads.
The amyloid precursor protein (APP) is a structurally and functionally conserved transmembrane protein whose physiological role in adult brain function and health is still unclear. Because mutations ...in APP cause familial Alzheimer's disease (fAD), most research focuses on this aspect of APP biology. We investigated the physiological function of APP in the adult brain using the fruit fly Drosophila melanogaster, which harbors a single APP homologue called APP Like (APPL). Previous studies have provided evidence for the implication of APPL in neuronal wiring and axonal growth through the Wnt signaling pathway during development. However, like APP, APPL continues to be expressed in all neurons of the adult brain where its functions and their molecular and cellular underpinnings are unknown. We report that APPL loss of function (LOF) results in the dysregulation of endolysosomal function in neurons, with a notable enlargement of early endosomal compartments followed by neuronal cell death and the accumulation of dead neurons in the brain during a critical period at a young age. These defects can be rescued by reduction in the levels of the early endosomal regulator Rab5, indicating a causal role of endosomal function for cell death. Finally, we show that the secreted extracellular domain of APPL interacts with glia and regulates the size of their endosomes, the expression of the Draper engulfment receptor, and the clearance of neuronal debris in an axotomy model. We propose that APP proteins represent a novel family of neuroglial signaling factors required for adult brain homeostasis.
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