Synthesis and characterization of silver nanoarticles from extract of Eucalyptus citriodora

The primary motivation for the study to develop simple eco-friendly green synthesis of silver nanoparticles using leaf extract of Eucalyptus citriodora as reducing and capping agent. The green synthesis process was quite fast and silver nanoparticles were formed within 0.5 h. The synthesis of the particles was observed by UV-visible spectroscopy by noting increase in absorbance. Characterization of the particles was carried out by X-ray diffraction, FTIR and electron microscopy. The developed nanoparticles demonstrated that E. citriodora is good source of reducing agents. UV-visible absorption spectra of the reaction medium containing silver nanoparticles showed maximum absorbance at 460 nm. FTIR analysis confirmed reduction of Ag+ to Ag0 atom in silver nanoparticles. The XRD pattern revealed the crystalline structure of silver nanoparticles. The SEM analysis showed the size and shape of the nanoparticles. The method being green, fast, easy and cost effective can be recommended for large scale production of AgNPs for their use in food, medicine and materials

A fresh look at the (non-)Abelian Landau-Khalatnikov-Fradkin transformations

The Landau-Khalatnikov-Fradkin transformations (LKFTs) allow to interpolate $n$-point functions between different gauges. We first offer an alternative derivation of these LKFTs for the gauge and fermions field in the Abelian (QED) case when working in the class of linear covariant gauges. Our derivation is based on the introduction of a gauge invariant transversal gauge field, which allows a natural generalization to the non-Abelian (QCD) case of the LKFTs. To our knowledge, within this rigorous formalism, this is the first construction of the LKFTs beyond QED. The renormalizability of our setup is guaranteed to all orders. We also offer a direct path integral derivation in the non-Abelian case, finding full consistency.Comment: 16 page

Novel approach for quantitative and qualitative authors research profiling using feature fusion and tree-based learning approach

Article citation creates a link between the cited and citing articles and is used as a basis for several parameters like author and journal impact factor, H-index, i10 index, etc., for scientific achievements. Citations also include self-citation which refers to article citation by the author himself. Self-citation is important to evaluate an author’s research profile and has gained popularity recently. Although different criteria are found in the literature regarding appropriate self-citation, self-citation does have a huge impact on a researcher’s scientific profile. This study carries out two cases in this regard. In case 1, the qualitative aspect of the author’s profile is analyzed using hand-crafted feature engineering techniques. The sentiments conveyed through citations are integral in assessing research quality, as they can signify appreciation, critique, or serve as a foundation for further research. Analyzing sentiments within in-text citations remains a formidable challenge, even with the utilization of automated sentiment annotations. For this purpose, this study employs machine learning models using term frequency (TF) and term frequency-inverse document frequency (TF-IDF). Random forest using TF with Synthetic Minority Oversampling Technique (SMOTE) achieved a 0.9727 score of accuracy. Case 2 deals with quantitative analysis and investigates direct and indirect self-citation. In this study, the top 2% of researchers in 2020 is considered as a baseline. For this purpose, the data of the top 25 Pakistani researchers are manually retrieved from this dataset, in addition to the citation information from the Web of Science (WoS). The selfcitation is estimated using the proposed model and results are compared with those obtained from WoS. Experimental results show a substantial difference between the two, as the ratio of self-citation from the proposed approach is higher than WoS. It is observed that the citations from the WoS for authors are overstated. For a comprehensive evaluation of the researcher's profile, both direct and indirect selfcitation must be included

Landau-Khalatnikov-Fradkin Transformations and the Fermion Propagator in Quantum Electrodynamics

We study the gauge covariance of the massive fermion propagator in three as well as four dimensional Quantum Electrodynamics (QED). Starting from its value at the lowest order in perturbation theory, we evaluate a non-perturbative expression for it by means of its Landau-Khalatnikov-Fradkin (LKF) transformation. We compare the perturbative expansion of our findings with the known one loop results and observe perfect agreement upto a gauge parameter independent term, a difference permitted by the structure of the LKF transformations.Comment: 9 pages, no figures, uses revte

Blockchain-enabled Reliable Osmotic Computing for Cloud of Things: Applications and Challenges

Cloud of Things (CoT) refers to an IoT solution consuming the cloud services of a single cloud vendor. In this paper, we have introduced the concept of a MultiCoT1 solution which refers to the collaborative execution of an IoT solution by multiple cloud vendors. Cloudlets and ad-hoc clouds are the extensions of centralized cloud services, closer to the user, in the form of fog and edge computing layers respectively and the Osmotic Computing (OC) serves as a glue by accomplishing the seamless compute sharing across these layers. The OC can also be integrated within a MultiCoT solution for extending it across three computational layers of cloud, fog and edge. However, this can only be achieved after establishing enough trust among all the vendors that are working in collaboration to simultaneously serve a particular MultiCoT solution. Blockchain has been already proven for establishing trust and supporting reliable interactions among independently operating entities. Hence, it can be used for establishing trust among the multiple cloud vendors serving a single MultiCoT solution. In this paper, we have presented the importance of using the proactive Blockchain-enabled Osmotic Manager (B-OM) for improving the reliability of OC. We have also highlighted the blockchain features that can improve the reliability of OC by establishing trust among the independently operating vendors of a MultiCoT solution, followed by the challenges associated with the integration of blockchain and OC along with the future research directions for achieving the proposed integration. © 2020 IEEE.Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works

A simple chemical approach to regenerating strength of thermally damaged glass fibre for reuse in composites

A key technical barrier to the reuse of thermally recycled glass fibres in composite applications is their low mechanical strength. This research study looks into the effect of alkaline treatments in regenerating the strength of glass fibres which were heated in a furnace to simulate thermal recycling conditions. Up to 100% strength increase of the fibres can be achieved through a simple treatment in alkaline solution. It was found that the nature of alkali, concentration, and treatment duration had a significant effect on the extent of strength recovery of the fibres. These treatments could potentially be implemented to thermally recycled glass fibres on an industrial scale, to allow their reprocessing into second-life composite materials. As well as optimising the reaction conditions to regenerate fibre strength, an examination of the surface morphology was carried out using various techniques. In addition, the kinetics of dissolution of glass fibres in alkaline solutions was investigated in order to further understand the strength regeneration mechanism

Landau-Khalatnikov-Fradkin transformations, Nielsen identities, their equivalence, and implications for QCD

The Landau-Khalatnikov-Fradkin transformations (LKFTs) represent an important tool for probing the gauge dependence of the correlation functions within the class of linear covariant gauges. Recently these transformations have been derived from first principles in the context of non-Abelian gauge theory (QCD) introducing a gauge invariant transverse gauge field expressible as an infinite power series in a Stueckelberg field. In this work we explicitly calculate the transformation for the gluon propagator, reproducing its dependence on the gauge parameter at the one-loop level and elucidating the role of the extra fields involved in this theoretical framework. Later on, employing a unifying scheme based upon the Becchi-Rouet-Stora-Tyutin symmetry and a resulting generalized Slavnov-Taylor identity, we establish the equivalence between the LKFTs and the Nielsen identities which are also known to connect results in different gauges

Coil-Assisted Retrograde Transvenous Obliteration (CARTO) for the Treatment of Portal Hypertensive Variceal Bleeding: Preliminary Results.

ObjectivesTo describe the technical feasibility, safety, and clinical outcomes of coil-assisted retrograde transvenous obliteration (CARTO) in treating portal hypertensive non-esophageal variceal hemorrhage.MethodsFrom October 2012 to December 2013, 20 patients who received CARTO for the treatment of portal hypertensive non-esophageal variceal bleeding were retrospectively evaluated. All 20 patients had at least 6-month follow-up. All patients had detachable coils placed to occlude the efferent shunt and retrograde gelfoam embolization to achieve complete thrombosis/obliteration of varices. Technical success, clinical success, rebleeding, and complications were evaluated at follow-up.ResultsA 100% technical success rate (defined as achieving complete occlusion of efferent shunt with complete thrombosis/obliteration of bleeding varices and/or stopping variceal bleeding) was demonstrated in all 20 patients. Clinical success rate (defined as no variceal rebleeding) was 100%. Follow-up computed tomography after CARTO demonstrated decrease in size with complete thrombosis and disappearance of the varices in all 20 patients. Thirteen out of the 20 had endoscopic confirmation of resolution of varices. Minor post-CARTO complications, including worsening of esophageal varices (not bleeding) and worsening of ascites/hydrothorax, were noted in 5 patients (25%). One patient passed away at 24 days after the CARTO due to systemic and portal venous thrombosis and multi-organ failure. Otherwise, no major complication was noted. No variceal rebleeding was noted in all 20 patients during mean follow-up of 384±154 days.ConclusionsCARTO appears to be a technically feasible and safe alternative to traditional balloon-occluded retrograde transvenous obliteration or transjugular intrahepatic portosystemic shunt, with excellent clinical outcomes in treating portal hypertensive non-esophageal variceal bleeding