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The present work aims to explore the mechanism of action of C-cinnamoyl glycoside as an antifilarial agent against the bovine filarial nematode Setaria cervi. Both apoptosis and autophagy programmed cell death pathways play a significant role in parasitic death. The generation of reactive oxygen species, alteration of the level of antioxidant components and disruption of mitochondrial membrane potential may be the causative factors that drive the parasitic death. Monitoring of autophagic flux via the formation of autophagosome and autophagolysosome was detected via CYTO ID dye. The expression profiling of both apoptotic and autophagic marker proteins strongly support the initial findings of these two cell death processes. The increased interaction of pro-autophagic protein Beclin1 with BCL-2 may promote apoptotic pathway by suppressing anti-apoptotic protein BCL-2 from its function. This in turn partially restrains the autophagic pathway by engaging Beclin1 in the complex. But overall positive increment in autophagic flux was observed. Dynamic interaction and regulative balance of these two critical cellular pathways play a decisive role in controlling disease pathogenesis. Therefore, the present experimental work may prosper the chance for C-cinnamoyl glycosides to become a potential antifilarial therapeutic in the upcoming day after detail in vivo study and proper clinical trial.
To examine self-reported practices and policies to reduce infection and transmission of multidrug-resistant organisms (MDRO) in healthcare settings outside the United States.
International members of the Society for Healthcare Epidemiology of America (SHEA) Research Network.
Electronic survey of infection control and prevention practices, capabilities, and barriers outside the United States and Canada. Participants were stratified according to their country’s economic development status as defined by the World Bank as low-income, lower-middle-income, upper-middle-income, and high-income.
A total of 76 respondents (33%) of 229 SHEA members outside the United States and Canada completed the survey questionnaire, representing 30 countries. Forty (53%) were high-, 33 (43%) were middle-, and 1 (1%) was a low-income country. Country data were missing for 2 respondents (3%). Of the 76 respondents, 64 (84%) reported having a formal or informal antibiotic stewardship program at their institution. High-income countries were more likely than middle-income countries to have existing MDRO policies (39/64 [61%] vs 25/64 [39%], P=.003) and to place patients with MDRO in contact precautions (40/72 [56%] vs 31/72 [44%], P=.05). Major barriers to preventing MDRO transmission included constrained resources (infrastructure, supplies, and trained staff) and challenges in changing provider behavior.
In this survey, a substantial proportion of institutions reported encountering barriers to implementing key MDRO prevention strategies. Interventions to address capacity building internationally are urgently needed. Data on the infection prevention practices of low income countries are needed.
Stalagmites and stalactites, as observed within natural caves, may develop inside geological repositories during constructional and post-operational periods. It is therefore important to understand actinide sorption within such materials. Towards this, experimental studies were carried out with 233U, 238Np (VI), 238Np (IV), 239Pu and 241Am radiotracers using natural speleothem samples collected from the Dharamjali cave of the Kumaon Lesser Himalayas, India. Petrological/mineralogical studies showed that natural speleothems have three general domains: (1) columnar calcite; (2) microcrystalline calcite; and (3) botryoidal aragonite – each with ferruginous materials. Results showed that all domains of speleothems can take up >99% actinides, irrespective of valence state and pH (1–6 range) of the solution. However, distribution coefficients were found to be at a maximum in aragonite for most of the actinides. Such data are very important for long-term performance and safety assessments of the deep geological repositories planned for the disposal of high-level nuclear wastes.
It is known that the flare component of solar X-ray emission is sensitive to the level of solar activity. The location of the X-ray flaring region is not directly known but can be inferred from the location of the associated Hα flare. A detailed study of more than 4000 solar X-ray flares recorded by UI and the NRL detectors during past eight years has shown that 85% of these flares definitely occurred in the active regions. For the rest 15% no definite conclusion was possible because either Hα flare data was not available or no Hα flare was reported within ± 15 min of these X-ray flares.
In a quasineutral plasma, electrons undergo collective oscillations, known as plasma oscillations, when perturbed locally. The oscillations propagate due to finite temperature effects. However, the wave can lose the phase coherence between constituting oscillators in an inhomogeneous plasma (phase mixing) because of the dependence of plasma oscillation frequency on plasma density. The longitudinal electric field associated with the wave may be used to accelerate electrons to high energies by exciting large amplitude wave. However when the maximum amplitude of the wave is reached that plasma can sustain, the wave breaks. The phenomena of wave breaking and phase mixing have applications in plasma heating and particle acceleration. For detailed experimental investigation of these phenomena a new device, inverse mirror plasma experimental device (IMPED), has been designed and fabricated. The detailed considerations taken before designing the device, so that different aspects of these phenomena can be studied in a controlled manner, are described. Specifications of different components of the IMPED machine and their flexibility aspects in upgrading, if necessary, are discussed. Initial results meeting the prerequisite condition of the plasma for such study, such as a quiescent, collisionless and uniform plasma, are presented. The machine produces δnnoise/n ⩽ 1%, Luniform ~ 120 cm at argon filling pressure of ~10−4 mbar and axial magnetic field of B = 1090 G.
A suite of sheared syenites occurring along the western margin of the Eastern Ghats Belt, India have developed extensive flame perthite in K-feldspar. Albite flames show large variation in size, shape and abundance. Field, petrographic and chemical evidence suggests complex interplay between differential stress, recycling of K-Na-Ca and supply of Na by infiltration for the development of flame perthite. Partial replacement of pyroxenes, plagioclase and alkali feldspar by amphibole, biotite, nepheline and calcite causes internal recycling of Na-Ca-K in a closed system. Representative compositions of the minerals are used to constrain the model dissolution–reprecipitation ion-exchange reactions involving Na and K either as reactants and/or as products. A substantial proportion of Na+ required for the development of the albite flames, originates from Na metasomatism accompanied by ductile shearing in the feldspathic rocks, providing an ideal open system wherein both the differential stress and Na+ are made available for the development of the flame perthites. This process probably augmented the replacement of K-feldspar grains by flame albite and the K+ released was carried away by the fluid or, possibly, augmented the biotite-forming reactions in the associated quartz-poor syenites and, hence, trigger the Na-K cycle in these rocks.
The relevance of the OECD and UN Model Conventions and their Commentaries
for the interpretation of Indian tax treaties
India is a common law country. In matters relating to interpretation, whether
involving domestic law or treaties, courts are the final arbiters. There is no
system of revenue ruling in India. No detailed guidelines are issued by the
Central Board of Direct Taxes (CBDT), the apex body in charge of the
administration of direct taxes. Occasionally, it issues public circulars for the
guidance of the officers. These are binding on the administration but not on the
taxpayer or the courts. Generally speaking, it is the case law that guides the
administration of direct taxes including the treaties.
Until 1980, there was no United Nations Model Double Taxation Convention between
Developed and Developing Countries (UN Model). Indian treaties for periods
before this time are closer to the OECD Model Tax Convention on Income and on
Capital (OECD Model). Subsequent treaties have been strongly influenced by the
UN Model, with greater emphasis on source taxation. Treaties with other
developing countries also have different nuances.
The courts in India have been taking recourse to the OECD Model Commentary for a
long time. The UN Model Commentary, having come late, has been of less use.
However, the tax officers often refer to it. Both the taxpayers and the tax
administrators routinely make reference to the Commentaries to suit their
convenience. As the UN Commentary has adopted the OECD Commentary for the most
part, there are very few cases where the UN Commentary has been preferred over
the OECD Commentary. There is also no guidance from the tax administration as to
whether either of the Models should be given priority.
A multiscale approach was adopted for the calculation of confined states in self-assembled semiconductor quantum dots (QDs). While results close to experimental data have been obtained with a combination of atomistic strain and tight-binding (TB) electronic structure description for the confined quantum states in the QD, the TB calculation requires substantial computational resources. To alleviate this problem an integrated approach was adopted to compute the energy states from a continuum 8-band k.p Hamiltonian under the influence of an atomistic strain field. Such multiscale simulations yield a roughly six-fold faster simulation. Atomic-resolution strain is added to the k.p Hamiltonian through interpolation onto a coarser continuum grid. Sufficient numerical accuracy is obtained by the multiscale approach. Optical transition wavelengths are within 7% of the corresponding TB results with a proper splitting of p-type sub-bands. The systematically lower emission wavelengths in k.p are attributable to an underestimation of the coupling between the conduction and valence bands.
Composite thin films of 60 wt% Ba0.6Sr0.4TiO3 and 40 wt% MgO were produced by Pulsed Laser Deposition. The biaxial texture of the BST component on the MgO substrate has been established with XRD. All as-deposited films had an enlarged BST out-of-plane lattice parameter. A more relaxed lattice constant as well as higher degree of texture has been obtained in the films deposited at higher temperature and lower deposition rate. Post-deposition annealing in flowing oxygen results in a further relaxation and alignment of the BST lattice. The as-deposited films were not tunable at room temperature. The greatest dielectric tuning was achieved in films annealed at 1200 °C. The observed difference in tunability for the films annealed at different temperatures may result from a spatial redistribution of BST material on the substrate surface during annealing.
Indium Phosphide (InP) based multilayer structures are becoming increasingly important in the semiconductor industry with optoelectronic applications being the main growth area. Mesa type structures with finely controlled width and etch angle, often form the building blocks for many of these photonic devices. Traditional wet etching techniques have often proved to be inadequate for the required anisotropie removal of material. This paper presents the results of etching semi-insulating InP (100) using a combination of an Argon ion beam and a reactive gas, CCl2F2 (Freon 12). It was found that the etch rate was enhanced by increasing the ion energy and by the addition of CCl2F2. Auger electron spectroscopy revealed that the increased etch rate was accompanied by an increase in the surface indium concentration and at low ion beam energies carbon build-up retarded the etch rate. The optimum etch angle to fabricate 3μm waveguides was found to be 22° to the surface normal, however Schottky contacts to these structures were unsuccessful.
We report the performance of 16-element phased array antennas operating at 30 GHz and ambient temperature. These antennas use BaxSr1−xTiO3(BST)-based phase shifters to produce the beam steering. Ferroelectric phase shifters offer advantages over current semiconductor and ferrite devices including faster switching speeds and lower costs. Also, ferroelectric phase shifters offer higher power handling capability than semiconductor devices and also have high radiation resistance. We made phase shifters from laser-ablated epitaxial BST films as well as from polycrystalline BST-oxide composite films. Although neither the devices nor the materials themselves are fully optimized, phase shifters have shown > 360° of phase shift with < 350 V DC bias (E < 9 V/µm) and ∼8 dB insertion loss. With ferroelectric phase shifters incorporated, antennas show radiation patterns with central-lobe half-power widths of ∼13° and side lobe intensities down by more than 10 dB. Using the phase shifters, the central lobe can be shifted, or “steered,” by ±18° in either direction. These results demonstrate a first step toward a prototype steerable antenna for 20–30 GHz satellite communications as well as other applications.
A monolithic quantum well infrared photodetector (QWIP) structure has been presented that is suitable for dual bands in the two atmospheric transmission windows of 3 – 5.3 μm and 7.5 – 14μm, respectively. The proposed structure employs dual stacked, strain InGaAs/AlGaAs and latticematched GaAs/AlGaAs quantum well infrared photodetector for mid wavelength and long wavelength detection. The response peak of the strain InGaAs/AlGaAs quantum well is at 4.9 μm and the lattice-matched GaAs/AlGaAs is at 10.5μm; their peak sensitivities are in the spectral regions of 3 – 5.3mu;m and 7.5 – 14μm. The peak responsivity when the dual-band QWIP is biased at 5 Volts is ∼0.065A/W at 4.9μm and ∼0.006A/W at 10.5μm; at this voltage the dual-band QWIP is more sensitive at the shorter wavelengths due to its larger impedance thus exhibiting wavelength tunability characteristics with bias. Additionally, single colored 4.9 and 10.5μm QWIPs were fabricated from the dual-band QWIP structure to study the bias-dependent behavior and also to understand the effects of growing the strain layer InGaAs/AlGaAs QWIP on top of the lattice-matched GaAs/AlGaAs QWIP. In summary, two stack dual-band QWIPs using GaAs/AlGaAs and strained InGaAs/AlGaAs multiquantum wells have been demonstrated with peak spectral sensitivities in the spectral region of 3 – 5.3μm and 7.5 – 14μm. Also, the voltage tunable dual-band detection have been realized for this kind of QWIP structure.
P-type InGaAs/InP quantum-well infrared photodetectors operated at 4.55 μm require the growth of ultra-thin (10 Å) quantum wells. We report a study of interfaces in QWIPs grown by gas-source molecular beam epitaxy in which we optimized the group V source supply sequence so that a 6 K photoluminescence linewidth as narrow as 8.4 meV was observed from a structure with 10 Å wells. Analysis of the PL suggests that interface roughness was minimized. Cross-sectional scanning tunneling microscopy, double crystal x-ray diffraction, and cross-sectional tunneling electron microscopy confirmed that high-quality interfaces and uniform layers were obtained. Using the derived structural parameters, photocurrent spectral response was theoretically predicted for these QWIPs and then experimentally verified.
We demonstrate that SiO2 cap rapid thermal annealing in ultra-thin p-type InGaAs/InP quantum wells can be used to produce large blue shifts of the band edge. A substantial bandgap blue shift, as much as 292.5 meV at 900°C has been measured and the value of the bandgap shift can be controlled by the anneal time. Theoretical modeling of the intermixing effect on the energy levels is performed based on the effective bond-orbital method, and we obtain a very good fit to the photoluminescence data. Compared to the as-grown detector, the peak spectral response of the annealed detector was shifted to longer wavelength without any major degradation in the responsivity characteristics.
A novel, low-cost, phased-array antenna that uniquely incorporates bulk phase shifting using voltage-tunable dielectric (VTD) material is presented. The array does not contain an individual phase shifter at each radiating element. This paper presents the antenna concept and describes how it can be used as a low-cost phased array. The VTDs that are used in this antenna are described. The measured antenna patterns of a prototype phased array demonstrating electronic beam scanning at 10 GHz are also presented.
We have investigated the effect of post-growth rapid thermal annealing (RTA) at different temperature on two InAs/GaAs bilayer quantum dots samples with different spacer thicknesses (7.5nm and 8.5nm). It is found that when RTA temperature gradually increases, there is usual blue shift of ground state emission peak wavelength for the sample having thinner spacer but for the other sample the emission peak sustains at same peak wavelength position upto a higher annealing temperature. The dots inside the sample with less spacer thickness dissolute much earlier (beyond 700°C annealing temperature) in comparison to the other sample. The structural and optical characterization has been done by cross sectional transmission electron microscope (XTEM) and low temperature photoluminescence (PL) experiments respectively.
The authors report a novel treatment of a case of type I laryngeal cleft diagnosed in an adult. They describe a technique of endoscopic obliteration of the posterior commissure defect. Initially, a test implant of starch and adrenaline was used, followed by permanent staged injections of Bioplastique™ to the posterior commissure. This rare congenital anomaly usually presents in childhood but late presentation should be considered when adults present with lifelong dysphonia especially when associated with gastro-oesophageal reflux disease.
—The sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) of gut supernate antigen (GS Ag) derived from partly fed Hyalomma anatolicum anatolicum Koch, 1844 (Acari: Ixodidae) adult females revealed 26 discrete potypeptide bands of molecular weight ranging from 25–208 kDa. Out of these, seven bandswere of major polypeptides with molecular weights of between 25.2 and 185.8 kDa. On immunoblotting with antisera raised in rabbits against gut supernate (crude extract), eight immunogenic polypeptides with molecular weights of between 51.7 and 185.8 were identified. The implications of these findings for the potential development of anti-tick vaccine are discussed.