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Decay of SARS-CoV-2 RNA along the wastewater treatment outfitted with Upflow Anaerobic Sludge Blanket (UASB) system evaluated through two sample concentration techniques
No full textFor the first time, we present, i) an account of decay in the genetic material loading of SARS-CoV-2 during Upflow Anaerobic Sludge Blanket (UASB) treatment of wastewater, and ii) comparative evaluation of polyethylene glycol (PEG), and ultrafiltration as virus concentration methods from wastewater for the quantification of SARS-CoV-2 genes. The objectives were achieved through tracking of SARS-CoV-2 genetic loadings i.e. ORF1ab, N and S protein genes on 8th and 27th May 2020 along the wastewater treatment plant (106000 m3 million liters per day) equipped with UASB system in Ahmedabad, India. PEG method performed better in removing materials inhibiting RT-qPCR for SARS-CoV-2 gene detection from the samples, as evident from constant and lower CT values of control (MS2). Using the PEG method, we found a reduction >1.3 log10 reduction in SARS-CoV-2 RNA abundance during UASB treatment, and the RNA was not detected at all in the final effluent. The study implies that i) conventional wastewater treatment systems is effective in SARS-CoV-2 RNA removal, and ii) UASB system significantly reduces SARS-CoV-2 genetic loadings. Finally, PEG method is recommended for better sensitivity and inhibition removal during SARS-CoV-2 RNA quantification in wastewater. � 2020 Elsevier B.V., All rights reserved
Nonperturbative heavy quark diffusion coefficients in a weakly magnetized thermal QCD medium
No full textIn this work, the perturbative and nonperturbative contributions to the heavy quark (HQ) momentum (kappa) as well as spatial (Ds) diffusion coefficients are computed in a weak background magnetic field. The formalism adopted here involves calculation of the in-medium potential of the HQ in a weak magnetic field, which then serves as a proxy for the resummed gluon propagator in the calculation of HQ self-energy (Sigma). The self-energy determines the scattering rate of HQs with light thermal partons, which is subsequently used to evaluate kappa and Ds. It is observed that nonperturbative effects play a dominant role at low temperature. The spatial diffusion coefficient, 2 pi TDs, exhibits good agreement with recent lattice QCD results. These findings can be applied to calculate the heavy quark directed flow at RHIC and LHC energies. An extension of this formalism to the case of finite HQ momentum has also been attempted
Complexity of warped conformal field theory
No full textWarped conformal field theories in two dimensions are exotic nonlocal, Lorentz violating field theories characterized by Virasoro�Kac�Moody symmetries and have attracted a lot of attention as candidate boundary duals to warped AdS3 spacetimes, thereby expanding the scope of holography beyond asymptotically AdS spacetimes. Here we investigate WCFT2�s using circuit complexity as a tool. First we compute the holographic volume complexity (CV) which displays a linear UV divergence structure, more akin to that of a local CFT2 and has a very complicated dependence on the Virasoro central charge c and the U(1) Kac�Moody level parameter k. Next we consider circuit complexity based on Virasoro�Kac�Moody symmetry gates where the complexity functional is the geometric (group) action on coadjoint orbits of the Virasoro�Kac�Moody group. We consider a special solution to extremization equations for which complexity scales linearly with �time�. In the semiclassical limit (large c,�k, while c/k remains finite and small) both the holographic volume complexity and circuit complexity scales with k. � 2023 Elsevier B.V., All rights reserved
Neutrinoless double beta decay from scalar leptoquarks: interplay with neutrino mass and flavor physics
No full textWe perform a comprehensive analysis of neutrinoless double beta (0νββ) decay and its interplay with low-energy flavor observables in a radiative neutrino mass model with scalar leptoquarks S1(3¯, 1, 1/3) and R~2321/6. We carve out the parameter region consistent with constraints from neutrino mass and mixing, collider searches, as well as measurements of several flavor observables, such as muon and electron anomalous magnetic moments, charged lepton flavor violation and rare (semi)leptonic kaon and B-meson decays, including the recent anomalies in RD∗ and B→Kνν¯ observables. We perform a global analysis to all the existing constraints and show the (anti)correlations between all relevant Yukawa couplings satisfying these restrictions. We find that the most stringent constraint on the parameter space comes from μ → e conversion in nuclei and K+→π+νν¯ decay. We also point out a tension between the muon and electron (g – 2) anomalies in this context. Taking benchmark values from the combined allowed regions, we study the implications for 0νββ decay including both the canonical light neutrino and the leptoquark contributions. We find that for normal ordering of neutrino masses, the leptoquark contribution removes the cancellation region that occurs for the canonical case. The effective mass in presence of leptoquarks can lie in the desert region between the standard normal and inverted ordering cases, and this can be probed in future ton-scale experiments like LEGEND-1000 and nEXO
Parameterized non-circular deviation from the Kerr paradigm and its observational signatures: extreme mass ratio inspirals and Lense-Thirring effect
No full textRecent gravitational wave observations and shadow imaging have demonstrated the astonishing consistency of the Kerr paradigm despite all the special symmetries assumed in deriving the Kerr metric. Hence, it is crucial to test the presence of these symmetries in astrophysical scenarios and constraint possible deviations from them, especially in strong field regimes. With this motivation, the present work aims to investigate the theoretical consequences and observational signatures of non-circularity in a unified theory-agnostic manner. For this purpose, we construct a parametrized non-circular metric with small deviations from Kerr. This metric preserves the other properties of Kerr, such as stationarity, axisymmetry, asymptotic flatness, and the equatorial reflection symmetry. Apart from the resulting mathematical simplifications, this assumption is crucial to disentangle the consequences of relaxing circularity from other properties. Then, after discussing various novel theoretical consequences, we perform a detailed analysis of extreme mass ratio inspirals and Lense-Thirring precession in the context of this newly constructed metric. Our study clearly shows the promising prospects of detecting and constraining even a slight non-circular deviation from the Kerr paradigm using the future gravitational wave observations by the Laser Interferometer Space Antenna
Multi-phase unbalanced AC–DC distribution system state estimation with benders decomposition
No full textState estimation for distribution system is an essential tool for monitoring and control operations such as energy management, Volt-VAR optimization, and load management. Therefore, the distribution system needs an effective monitoring system. However, the advancement in information and communication technology (ICT), such as advanced metering infrastructures and synchrophasors, has made the distribution system more observable and therefore, relatively convenient for state estimation. Moreover, monitoring the distribution system is challenging due to its unbalanced & multi-phase nature, limited measurements, and numerous nodes. The topological challenges for distribution systems include network configuration, such as weakly meshed and radial networks. The distribution system has a resistance-to-reactance ratio greater than one, which makes it prone to ill-conditioning. Further, imposing the additional challenge of Jacobian matrix inversion, which causes difficulty to apply the gradient-based optimization methods. On the other hand, the distribution networks accommodate the distributed energy resources, AC power flow and DC power flow forming an integrated network of AC–DC distribution. The AC–DC systems are coupled with power electronics converters. Therefore, a combined state estimation technique with an AC–DC system is necessary for effective monitoring and control decision-making. There is a challenge for combined AC–DC systems owing to topological characteristics and modelling of the power electronics converters for steady-state operation along with their control strategy. Thus, the simplified power electronics converter models are developed in this work for AC–DC distribution system state estimation (DSSE). However, DSSE is a mathematically intensive large-scale optimization problem and requires a substantial computational resource. Mathematical complexities include ill-condition Jacobian matrix inversion and time complexity challenges for large-scale optimization. The estimation problem formulated as a non-linear mathematical program adds the computational burden for the large-scale optimization problem. The other challenges, such as structural and mathematical complexity, have provided the pathway for decomposing larger problems into smaller sub-problems for improved efficiency in solving optimization problems. Hence, this work proposes the DSSE formulation as a linear optimization problem for the unbalanced multi-phase AC–DC distribution system. This work proposes a Benders decomposition-based AC–DC DSSE algorithm to address the above challenges and improve efficiency of solving the large-scale DSSE optimization problems. To demonstrate the effectiveness of the proposed DSSE algorithm, it is implemented on the distribution test system having the radial and meshed configurations with unbalanced network condition such as the IEEE 33-node system, modified IEEE 13-node, and IEEE 123-node unbalanced multi-phase AC–DC distribution systems. The accuracy of the proposed algorithm is compared with the existing literature, showing robustness to noise and ill-conditioned network. The developed method is implemented on large-scale network demonstrating the scalability and ease of implementation
Graphene oxide nanocells for impairing topoisomerase and DNA in cancer cells
No full textDNA topoisomerases and nuclear DNA are important targets for cancer therapy. However, DNA topoisomerase inhibitors and DNA damaging drugs demonstrate a large window of side effects in the clinic. Graphene oxide based biocompatible and biodegradable nano-scale materials have the potential to overcome this complication. However, encompassing different topoisomerase inhibitors along with DNA damaging drugs into 2D-graphene oxide remains a main challenge. To address this, in this manuscript, we have engineered self-assembled spherical 3D-graphene oxide nanoparticles coated with lipid (GO-nanocells) which can concomitantly load and release multiple topoisomerase inhibitors (topotecan and doxorubicin) and DNA damaging drug (cisplatin) in a controlled manner. Fluorescence confocal microscopy confirmed that these GO-nanocells were taken up by HeLa cervical cancer cells and transported into lysosomes temporally over 6 h. A combination of confocal microscopy, gel electrophoresis, and flow cytometry studies revealed that these GO-nanocells damaged nuclear DNA along with topoisomerase inhibition leading to induction of apoptosis through cell cycle arrest in the G2-M phase. These GO-nanocells killed HeLa cancer cells with remarkably greater efficacy compared to a free drug cocktail at 48 h post-incubation. These self-assembled GO-nanocells can serve as a nanoscale tool to perturb multiple therapeutically important sub-cellular targets simultaneously for improved efficacy in future cancer chemotherapy. � 2019 Elsevier B.V., All rights reserved
Plastic strain triggers structural instabilities upon cyclic loading in ultrafine-grained nickel
No full textGrain growth accompanied by shear band formation shortens lifetime of nanostructured metals upon cyclic loading. Although the occurrence of structural instabilities was reported frequently, the difficulty to detect and track their initiation and evolution using standard testing routines prevents an in-depth understanding of the underlying mechanisms. Usage of samples from different synthesis routes tested under varying conditions further complicates this issue. Here, cyclic high pressure torsion is presented as an alternative method to mimic low cycle fatigue. It allows to study initiation and evolution of structural instabilities reproducibly up to enormous accumulated strains, not accessible in conventional fatigue tests. It enabled a general understanding of the processes causing structural instabilities in nanostructured nickel tested with different parameters such as strain amplitude or temperature. Grain coarsening starts from the very first cycles and initiates strain localization in shear bands. Accumulation of cyclic strain induces progressive growth of the shear band thickness accompanied by further grain growth within these bands. Clearly, cyclic strain amplifies grain coarsening suggesting that not the applied stress alone forces boundary motion. This is emphasized further as preferential texture components which facilitate cyclic slip evolve. Although the imposed cyclic strain drives grain growth it stagnates at certain grain sizes. Experiments at 77 K revealed identical instabilities, proving that for nickel boundary migration occurred predominantly mechanically driven. � 2020 Elsevier B.V., All rights reserved