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The performance and transient stabilizing using a unified power flow controller (UPFC) anticipated for a grid consisting of parallel connected two number of three-phase transmission lines is presented in this paper. The interruption that happened in absence of UPFC connected to three phase line increases the impedance of the transmission line and consequently reduces the flow of active power. The volume of active power flowing through the grid can be controlled by installing UPFC on the grid. The conditions for transient stability are suggested by the transient model and UPFC interconnected power grid. The complete dynamic control is modeled by the active and reactive power waves developed during transient events. A series of simulations are presented in this paper to show the effectiveness and correctness of the methodology applied for transient stability. [ABSTRACT FROM AUTHOR]

Unlike other malignancies, therapeutic options in pancreatic ductal adenocarcinoma (PDAC) are largely limited to cytotoxic chemotherapy without the benefit of molecular markers predicting response. Here we report tumor-cell-intrinsic chromatin accessibility patterns of treatment-naïve surgically resected PDAC tumors that were subsequently treated with (Gem)/Abraxane adjuvant chemotherapy. By ATAC-seq analyses of EpCAM+ PDAC malignant epithelial cells sorted from 54 freshly resected human tumors, we show here the discovery of a signature of 1092 chromatin loci displaying differential accessibility between patients with disease free survival (DFS) < 1 year and patients with DFS > 1 year. Analyzing transcription factor (TF) binding motifs within these loci, we identify two TFs (ZKSCAN1 and HNF1b) displaying differential nuclear localization between patients with short vs. long DFS. We further develop a chromatin accessibility microarray methodology termed "ATAC-array", an easy-to-use platform obviating the time and cost of next generation sequencing. Applying this methodology to the original ATAC-seq libraries as well as independent libraries generated from patient-derived organoids, we validate ATAC-array technology in both the original ATAC-seq cohort as well as in an independent validation cohort. We conclude that PDAC prognosis can be predicted by ATAC-array, which represents a low-cost, clinically feasible technology for assessing chromatin accessibility profiles. ATAC-seq allows for the investigation of chromatin accessibility, a feature which can have important implications for gene regulation. Here the authors present ATAC-array to assess accessibility in human tumours and based on this predict disease prognosis. [ABSTRACT FROM AUTHOR]

This paper presents studies on direct non-destructive determination of uranium in sintered deeply depleted (DD) uranium oxide (UO2) pellets by wavelength dispersive X-ray fluorescence (WDXRF) spectrometry. A special collet was designed and fabricated for holding the sintered DDUO2 pellets for direct analysis, thus avoiding the sample preparation steps. The samples were analyzed using a calibration plot obtained from WDXRF spectra of matrix matched calibration standards. The WDXRF determined uranium values were found to be in very close agreement with titrimetric values and has reproducibility better than 0.05% (RSD, 1 s, n = 10) for the sintered DDUO2 pellets having U: 86.81–88.04 wt%. [ABSTRACT FROM AUTHOR]

A precise and accurate compositional characterization methodology using wavelength dispersive X-ray fluorescence (WDXRF) spectrometry for mixed oxide nuclear fuels is reported. The methodology involves pelletization of standards and samples. The calibration plots were made by plotting the percent intensity of analyte X-ray lines against their amount percent. The relative standard deviation were 0.4% and 0.25%, respectively for uranium and thorium, having U ranging from 2.85 to 4.2 (wt%). The analytical results were compared with chemical analysis method and were in good agreement. The developed WDXRF method is non-destructive, fast and better in comparison to chemical analysis methods. [ABSTRACT FROM AUTHOR]

A radiotracer technique has been used to achieve the carrier-free separation of 115mIn from its parent 115Cd in hydrochloric acid medium on a chromatographic column packed with TODGA-impregnated silica gel. At 8 M HCl, both cations are bound at the chelating site, which results in maximum adsorption. When the column is treated with 2 M HCl, the daughter complex gets desorbed and is eluted from the column, whereas the parent remains undisturbed. Pure silica gel does not adsorb radioactivity under these conditions. The radiochemical purity of daughter was checked by its half-life (4.49 h). [ABSTRACT FROM AUTHOR]

The biocompatibility of an implant material depends on the bulk physical properties as well as on the surface properties. Titanium alloy Ti6Al4V is a very popular biological implant material for its bulk physical properties resembling those of natural bone. It is possible to modify the surface properties of Ti6Al4V by laser irradiation. In the current study, using continuous wave fibre laser, grooves of different depths and widths have been created by varying laser power and scan speed. Laser frequency and duty cycle were varied to alter the inside surface topographies of the microgrooves. The surface wettability and the protein adsorption on the surface were found to be dependent on the microtexture parameters. To understand the effect of this type of texturing on the cell behaviour, MG63 cells have been cultured on the sample surfaces, and the result was studied after 3 and 5 days of cell culture. Surface features dimensionally closer to the cell dimensions are able to positively affect the viability and spreading of MG63 cells, as seen from this study. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Among several spectroscopic imaging techniques to visualise the nanostructures, Raman spectral imaging is one of the most indispensible non-destructive tools. We discuss the limitations and the importance of each step involved in the Raman imaging in the visualization of different nanostructures and illustrated with examples. Raman spectroscopic imaging of nanostructures is demonstrated for differentiation of morphology in InN nanorods, crystallographic orientation for single square faceted GaN nanotube and layer thickness of graphene layers. The limitations of the spatial and spectral resolutions of the Raman maps are evaluated in the illustration. [ABSTRACT FROM AUTHOR]

Understanding the mechanism of nanoparticle (NP) induced toxicity in microbes is of potential importance to a variety of disciplines including disease diagnostics, biomedical implants, and environmental analysis. In this context, toxicity to bacterial cells and inhibition of biofilm formation by GaN NPs and their functional derivatives have been investigated against gram positive and gram negative bacterial species down to single cellular level. High levels of inhibition of biofilm formation (>80 %) was observed on treatments with GaN NPs at sub-micro molar concentrations. These results were substantiated with morphological features investigated with field emission scanning electron microscope, and the observed changes in vibrational modes of microbial cells using Raman spectroscopy. Raman spectra provided molecular interpretation of cell damage by registering signatures of molecular vibrations of individual living microbial cells and mapping the interplay of proteins at the cell membrane. As compared to the untreated cells, Raman spectra of NP-treated cells showed an increase in the intensities of characteristic protein bands, which confirmed membrane damage and subsequent release of cellular contents outside the cells. Raman spectral mapping at single cellular level can facilitate understanding of the mechanistic aspect of toxicity of GaN NPs. The effect may be correlated to passive diffusion causing mechanical damage to the membrane or ingress of Ga (ionic radius ~0.076 nm) which can potentially interfere with bacterial metabolism, as it resembles Fe (ionic radius ~0.077 nm), which is essential for energy metabolism. [ABSTRACT FROM AUTHOR]

Large scale square-shaped wurtzite-GaN nanotubes are synthesized by a quasi-vapor-solid process. GaN nanotubes, functionalized with ultra-small Pt nanocluster via green chemistry route, provide extraordinary physicochemical properties instigated by laser power exposure and local ambience. Laser irradiation-induced localized catalytic oxidation and catastrophic photo-fragmentation in individual nanotubes is observed as a result of rapid crystallo-chemical transformation. The auto-amplified electronic cascades inside the Pt nanoclusters, upon exposure to high laser fluency, reinforce strong energy deposition in the proximity of the metal-semiconductor interface. This process leads to ballistic recombination with the available photo-generated O ionized/radical species to yield chemisorbed oxide layer of GaO. It has been demonstrated to bisect or oxidize a selected region of a single GaN nanotube by modulating the incident laser power, gas ambience, and its kinetics. [ABSTRACT FROM AUTHOR]

A novel inorganic ion exchanger, aluminum tungstate, was prepared and characterized by spectroscopic tools and elemental analysis. The compound is resistant to heat and radiation and is stable in diverse chemical environments. This material exhibits an excellent adsorption of parent-daughter Cs-Ba. The newly prepared crystalline inorganic ion exchanger was employed for separation of the carrier-free Ba from Cs using 0.0426 M ascorbic acid solution as eluting agent. Trend in elution is encouraging to apply the system as radionuclide generator. [ABSTRACT FROM AUTHOR]

We report simultaneous measurements of shear viscosity ( η) and dielectric constant ( ε) of octyloxy cyanobiphenyl (8OCB) in the nematic (N) and smectic-A (SmA) phases as functions of temperature and electric field. With increasing electric field η increases in the N phase whereas it decreases in the SmA phase and saturates beyond a particular field in both the phases. The flow curves in the intermediate-field range show two Newtonian regimes in the N phase. The temperature-dependent behavior of η and ε at zero or at small electric field suggests the occurrence of several structures that results from precessional motion of the director along the neutral direction as reported in similar other system. We show that the precessional motions are gradually suppressed with increasing electric field and the effective viscosity resembles with the Miesowicz viscosity η at high enough electric field. In the intermediate field range the temperature-dependent η exhibits anomalous behavior across the N-SmA phase transition which is attributed to the large contribution of Leslie coefficient α . [ABSTRACT FROM AUTHOR]

Indium nanoclusters are synthesized in an amorphous silica matrix using an ion-implantation technique. Indium ions (In2+) with energy of 890 keV are implanted on silica to fluences in the range of 3×1016–3×1017 cm-2. The formation of indium nanoclusters is confirmed by optical absorption spectrometry and glancing incidence X-ray diffraction studies. A low frequency Raman scattering technique is used to study the growth of embedded indium nanoclusters in the silica matrix as a function of fluence and post-implantation annealing duration. Rutherford backscattering spectrometry studies show the surface segregation of implanted indium. Photoluminescence studies indicate the formation of a small quantity of indium oxide phase in the ion-implanted samples. [ABSTRACT FROM AUTHOR]

We report the experimental high electric field phase diagram of a nematic liquid crystal which exhibits a large negative dielectric anisotropy. We measure simultaneously the birefringence (Δn) and the dielectric constant (epsilon⊥) at various applied fields as functions of the local temperature of an aligned sample. We also measure the higher harmonics of the electrical response of the medium. The following experimental results are noted: (i) enhancement of orientational order parameter S in the nematic phase due to both the Kerr effect and quenching of director fluctuations; (ii) enhancement in the paranematic to nematic transition temperature (TPN) with field; (iii) divergence of the order parameter susceptibility beyond the tricritical point as measured by third harmonic electrical signal; (iv) a small second harmonic electrical signal which also diverges near TPN, indicating the presence of polarised domains. Our measurements show that ΔTPN(= TPN(E)-TNI(0)) varies linearly with |E| whereas the Landau de Gennes theory predicts a dependence on E2. It is argued that the quenching of director fluctuations by the field makes the dominant contribution to all the observations, including the thermodynamics of the transition. [ABSTRACT FROM AUTHOR]

An early step in the carcinogenesis of hereditary non-polyposis colorectal cancer (HNPCC) and some sporadic colorectal cancers (CRCs) is the acquisition of a 'mutator phenotype' resulting from defects in DNA mismatch repair (MMR) genes, which normally maintain genomic stability. This mutator phenotype causes an approximately 100-1000-fold increase in base substitutions and small insertion/deletion mutations thereby driving carcinogenesis. It also causes genome-wide microsatellite instability (MSI) due to the inability to repair mutations within these small, hard to replicate, repetitive DNA elements. In contrast, less is known about the role of mutator phenotypes in microsatellite stable (MSS) CRC. In this report, we have measured the mutation rates in 11 MSS CRC cell lines to obtain an estimate of the prevalence of mutator phenotypes in MSS carcinogenesis. Of the 11 cell lines, three of them (27%) possess spontaneous hypoxanthine phosphoribosyltransferase mutation rates approximately 10-100-fold above background. When challenged with alkylating and oxidising agents, the degree of survival and apoptotic responses are different, indicating that these cell lines may represent more than one mutator phenotype. These data demonstrate that a significant portion of MSS CRC cell lines has increased mutation rates and that this may play a role in MSS CRC carcinogenesis. [ABSTRACT FROM AUTHOR]

Copyright of Microchimica Acta is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

The emerging field of valleytronics aims to coherently manipulate an electron and/or hole's valley pseudospin as an information bearing degree of freedom (DOF). Monolayer transition metal dichalcogenides, due to their strongly bound excitons, their degenerate valleys and their seamless interfacing with photons are a promising candidate for room temperature valleytronics. Although the exciton binding energy suggests room temperature valley coherence should be possible, it has been elusive to-date. A potential solution involves the formation of half-light, half-matter cavity polaritons based on 2D material excitons. It has recently been discovered that cavity polaritons can inherit the valley DOF. Here, we demonstrate the room temperature valley coherence of valley-polaritons by embedding a monolayer of tungsten diselenide in a monolithic dielectric cavity. The extra decay path introduced by the exciton-cavity coupling, which is free from decoherence, is the key to room temperature valley coherence preservation. These observations paves the way for practical valleytronic devices. Owing to the presence of strongly bound excitons and degenerate valleys, monolayer transition metal dichalcogenides show promise for valleytronic applications. Here, the authors embed monolayer WSe2 in a monolithic dielectric cavity, and observe room-temperature valley coherence of valley-polaritons. [ABSTRACT FROM AUTHOR]