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Protective Role of Decellularized Human Amniotic Membrane from Oxidative Stress-Induced Damage on Retinal Pigment Epithelial Cells
No full textOxidative stress is an important cause for several retinal aging diseases. Cell therapy using a decellularized human amniotic membrane (dHAM) as a tissue scaffold for retinal pigment epithelial cells has a potential therapeutic role under such pathological conditions. This is attributed by the anti-inflammatory, antimicrobial, low-immunogenicity aspects of dHAM, apart from harboring a drug reservoir potential. The underlying mechanisms for maintaining the physiological properties of transplanted cells and their survival in a diseased milieu using dHAM has remained unexplored/unanswered. Hence, we investigated the potential role of dHAM in preserving the cellular functions of retinal pigment epithelium in an oxidative stress environment. Adult human retinal pigment epithelial (ARPE-19) cells were cultured on dHAM or tissue culture dishes under hyperoxia. Gene expression, immunofluorescence staining, enzyme-linked immunosorbent assay (ELISA), and scanning electron microscopy (SEM) were performed to assess the levels of reactive oxygen species, proliferation, apoptosis, epithelial-mesenchymal transition, phagocytosis, and secretion of vascular endothelial factors. These results indicate reduced epithelial-mesenchymal transition, generation of reactive oxygen species (p <= 0.0001), and apoptosis (p <= 0.05) in cells cultured on dHAM, compared to those on tissue culture dishes under oxidative stress conditions. Concomitantly, the secretion of the vascular endothelial growth factor was significantly reduced (p <= 0.01) on dHAM. Phagocytic activity was significantly higher (p <= 0.001) in cells cultured on dHAM and were comparable to those cells cultured on tissue culture dishes. SEM images showed a clustered growth pattern on dHAM compared to an elongated morphology when cultured on tissue culture dishes under oxidative stress conditions. These findings demonstrate the utility of dHAM as a scaffold for growing retinal epithelial cells and to maintain their physiological properties in an oxidative stress condition with a potential to develop regenerative medicine strategies to treat degenerative eye diseases
Search for single production of vector-like quarks decaying to a top quark and a W boson in proton-proton collisions at TeV
No full textA search is presented for the single production of vector-like quarks in proton-proton collisions at TeV. The data, corresponding to an integrated luminosity of 35.9fb-1, were recorded with the CMS experiment at the LHC. The analysis focuses on the vector-like quark decay into a top quark and a W boson, with one muon or electron in the final state. The mass of the vector-like quark candidate is reconstructed from hadronic jets, the lepton, and the missing transverse momentum. Methods for the identification of b quarks and of highly Lorentz boosted hadronically decaying top quarks and W bosons are exploited in this search. No significant deviation from the standard model background expectation is observed. Exclusion limits at 95% confidence level are set on the product of the production cross section and branching fraction as a function of the vector-like quark mass, which range from 0.3 to 0.03pb for vector-like quark masses of 700 to 2000GeV. Mass exclusion limits up to 1660GeV are obtained, depending on the vector-like quark type, coupling, and decay width. These represent the most stringent exclusion limits for the single production of vector-like quarks in this channel
Electrochemical paper based cancer biosensor using iron oxide nanoparticles decorated PEDOT:PSS
No full textWe report results of the studies relating to the fabrication of a label-free, flexible, light weight and disposable conducting paper based immunosensing platform comprising of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) and nanostructured iron oxide (nFe(2)O(3)@PEDOT:PSS) nanocomposite for detection of carcinoembryonic antigen (CEA), a cancer biomarker. The effect of various solvents such as sorbitol, ethanol, propanol, n-methyl-2-pyrrolidone (NMP) and dimethyl sulfoxide (DMSO) on the electrical conductivity of Whatman filter paper (WP) modified with nFe(2)O(3)@PEDOT:PSS/WP was investigated. The electrical conductivity of the PEDOT:PSS/WP electrode was found to be enhanced by two orders of magnitude (from 6.8 x 10(-4) to 1.92 x 10(-2) Scm(-1)) after its treatment with DMSO. Further, nFe(2)O(3) doped PEDOT:PSS/WP electrode exhibited the electrical conductivity as 2.4 x 10(-2) Scm(-1). Besides this, the incorporation of iron oxide nanoparticles (nFe(2)O(3)) into PEDOT:PSS/ WP resulted in improved electrochemical performance and signal stability. This nFe(2)O(3)@ PEDOT:PSS/WP based platform was used for immobilization of the anti-carcinoembronic antigen (anti-CEA) protein for quantitative estimation of cancer biomarker (CEA). The results of electrochemical response studies revealed that this conducting paper based immunoelectrode had a sensitivity of 10.2 mu Ang(-1) mLcm(-2) in the physiological range (4-25 ngmL(-1)) and shelf life of 34 days. Further, the proposed immunoelectrode was validated with conventional ELISA for the detection of CEA in serum samples of cancer patients. (C) 2019 Elsevier B.V. All rights reserved
Serum biomarkers identification by iTRAQ and verification by MRM: S100A8/S100A9 levels predict tumor-stroma involvement and prognosis in Glioblastoma
No full textDespite advances in biology and treatment modalities, the prognosis of glioblastoma (GBM) remains poor. Serum reflects disease macroenvironment and thus provides a less invasive means to diagnose and monitor a diseased condition. By employing 4-plex iTRAQ methodology, we identified 40 proteins with differential abundance in GBM sera. The high abundance of serum S100A8/S100A9 was verified by multiple reaction monitoring (MRM). ELISA and MRM-based quantitation showed a significant positive correlation. Further, an integrated investigation using stromal, tumor purity and cell type scores demonstrated an enrichment of myeloid cell lineage in the GBM tumor microenvironment. Transcript levels of S100A8/S100A9 were found to be independent poor prognostic indicators in GBM. Medium levels of pre-operative and three-month post-operative follow-up serum S100A8 levels predicted poor prognosis in GBM patients who lived beyond median survival. In vitro experiments showed that recombinant S100A8/S100A9 proteins promoted integrin signalling dependent glioma cell migration and invasion up to a threshold level of concentrations. Thus, we have discovered GBM serum marker by iTRAQ and verified by MRM. We also demonstrate interplay between tumor micro and macroenvironment and identified S100A8 as a potential marker with diagnostic and prognostic value in GBM. © 2019, The Author(s)
An algorithm for triangulating smooth three-dimensional domains immersed in universal meshes
No full textWe describe an algorithm to recover a boundary-fitting triangulation for a bounded C-2-regular domain omega subset of R3 immersed in a nonconforming background mesh of tetrahedra. The algorithm consists in identifying a polyhedral domain omega(h) bounded by facets in the background mesh and morphing omega(h) into a boundary-fitting polyhedral approximation omega(h) of omega. We discuss assumptions on the regularity of the domain, on element sizes and on specific angles in the background mesh that appear to render the algorithm robust. With the distinctive feature of involving just small perturbations of a few elements of the background mesh that are in the vicinity of the immersed boundary, the algorithm is designed to benefit numerical schemes for simulating free and moving boundary problems. In such problems, it is now possible to immerse an evolving geometry in the same background mesh, called a universal mesh, and recover conforming discretizations for it. In particular, the algorithm entirely avoids remeshing-type operations and its complexity scales approximately linearly with the number of elements in the vicinity of the immersed boundary. We include detailed examples examining its performance
On symmetry preserving and symmetry broken bright, dark and antidark soliton solutions of nonlocal nonlinear Schrodinger equation
No full textWe construct symmetry preserving and symmetry broken N-bright, dark and antidark soliton solutions of a nonlocal nonlinear Schrodinger equation. To obtain these solutions, we use appropriate eigenfunctions in Darboux transformation (DT) method. We present explicit one and two bright soliton solutions and show that they exhibit stable structures only when we combine the field and parity transformed complex conjugate field. Further, we derive two dark/antidark soliton solution with the help of DT method. Unlike the bright soliton case, dark/antidark soliton solution exhibits stable structure for the field and the parity transformed conjugate field separately. In the darkiantidark soliton solution case we observe a contrasting behaviour between the envelope of the field and parity transformed complex conjugate envelope of the field. For a particular parametric choice, we get dark (antidark) soliton for the field while the parity transformed complex conjugate field exhibits antidark (dark) soliton. Due to this surprising result, both the field and PT transformed complex conjugate field exhibit sixteen different combinations of collision scenario. We classify the parametric regions of dark and antidark solitons in both the field and parity transformed complex conjugate field by carrying out relevant asymptotic analysis. Further we present 2N-dark/antidark soliton solution formula and demonstrate that this solution may have 2(2N) x 2(2N) combinations of collisions. (C) 2018 Elsevier B.V. All rights reserved
Reducing uncertainties in estimating long-time prestress losses in concrete structures using a hygro-thermo-chemo-mechanical model for concrete
No full textPrestress losses occur in concrete structures due to long-time creep and shrinkage in concrete, and stress relaxation in prestressing strands. The existing formulations for creep and shrinkage modeling in concrete are empirical in nature, which have been developed based on a particular set of measured data. In this study a coupled hygro-thermo-mechanical formulation is used to model the physics associated with creep and shrinkage in concrete structures. Uncertainty tools based on a probabilistic framework are used to model the possible variations in the input variables in the hygro-thermo-mechanical formulation. A distance measure based global response sensitivity analysis is adopted to identify the parameters having maximum impact on the output responses. Uncertainties in the selected set of important variables are reduced using Bayesian inference and short-time measured responses. For validating efficiency of the uncertainty reduction technique adopting Bayesian inference and global response sensitivity, the predictions of creep and shrinkage in concrete are compared with a few experiments from the North-Western University (NU) data base. The uncertainty reduction technique is then used to predict the long-time prestress losses in post-tensioned concrete beams and slabs cast in the laboratory. (C) 2018 Elsevier Ltd. All rights reserved
Understanding the Mechanism of Dynamic Recrystallization During High-Temperature Deformation in Nb-1Zr-0.1C Alloy
No full textIn the present investigation, a systematic study of the evolution of microstructure and crystallographic texture during hot deformation of Nb-1Zr-0.1C was carried out in the temperature range 1773-1973K (1500-1700 degrees C) at different strain rates of 0.001, 0.01 and 0.1s(-1). The aim was to examine the mechanisms of dynamic recovery and recrystallization in a high-temperature range. A detailed microstructural analysis of the deformed samples was performed using the electron backscatter diffraction technique to study the occurrence and nature of various dynamic restoration processes; the different regimes of dynamic recovery and recrystallization were identified. The orientations of the dynamically recrystallized grains were found to be (001) <uvw>
Temperature sensor based on multi-layer MoS2 coated etched fiber Bragg grating
No full textThe development of an etched fiber Bragg grating (eFBG)-based temperature sensor with a uniform multi-layer molybdenum-di-sulphide (MoS2) coating is presented in this paper. Multi-layer MoS2 has been coated on clad etched FBG sensors by DC magnetron sputtering of molybdenum (Mo) and subsequent sulfurization. The dependence of temperature sensitivity on the coating thickness of MoS2 on eFBGs has been tested from room temperature to 100 degrees C. It has been found that MoS2 coated clad etched FBG sensors with a coating thickness of around 10 tun exhibit a maximum temperature sensitivity of similar to 95 pm/degrees C (almost one order higher than that of bare fiber Bragg gratings), with a resolution of similar to 0.01 degrees C obtained using an FBG interrogator with 1 pm resolution. (C) 2019 Optical Society of Americ
Same-sign multilepton signatures of an SU(2)(R) quintuplet at the LHC
No full textWe study in detail the collider signatures of an SU(2)(R) fermionic quintuplet in the framework of left-right symmetric model in the context of the 13 TeV LHC. Apart from giving a viable dark matter candidate ((0)), this model provides unique collider imprints in the form of same-sign multileptons through the decays of multi-charged components of the quintuplet. In particular, we consider the scenario where the quintuplet carries (B - L) = 4 charge, allowing for the presence of high charge-multiplicity particles with relatively larger mass differences among them compared to (B - L) = 0 or 2. In this paper, we mainly focus on the same-sign n-lepton signatures (nSSL). We show that with an integrated luminosity of 500 fb(-1), the mass of the neutral component, M0 480 (800) GeV can be excluded at 95% CL in the 2SSL (3SSL) channel after imposing several selection criteria. We also show that a 5 sigma discovery is also achievable if M0 390 (750) GeV in the 2SSL (3SSL) channel with 1000 fb(-1) integrated luminosity