Abstract
The Fermi fourth catalog of active galactic nuclei (AGNs) data release 3 (4LAC-DR3) contains 3407 AGNs, out of which 755 are flat spectrum radio quasars (FSRQs), 1379 are BL Lacertae objects ...(BL Lac objects), 1208 are blazars of unknown (BCUs) type, while 65 are non-AGNs. Accurate categorization of many unassociated blazars still remains a challenge due to the lack of sufficient optical spectral information. The aim of this work is to use high-precision, optimized machine-learning (ML) algorithms to classify BCUs into BL Lac objects and FSRQs. To address this, we selected the 4LAC-DR3 Clean sample (i.e., sources with no analysis flags) containing 1115 BCUs. We employ five different supervised ML algorithms, namely, random forest, logistic regression, XGBoost, CatBoost, and neural network with seven features: photon index, synchrotron-peak frequency, pivot energy, photon index at pivot energy, fractional variability,
ν
F
ν
, at synchrotron-peak frequency, and variability index. Combining results from all models leads to better accuracy and more robust predictions. These five methods together classified 610 BCUs as BL Lac objects and 333 BCUs as FSRQs with a classification metric area under the curve >0.96. Our results are significantly compatible with recent studies as well. The output from this study provides a larger blazar sample with many new targets that could be used for forthcoming multiwavelength surveys. This work can be further extended by adding features in X-rays, UV, visible, and radio wavelengths.
Purpose
– The purpose of this paper is to examine the effects of contextual variables – organisational justice (procedural justice, interactional justice and psychological contract) and trust – on ...work engagement.
Design/methodology/approach
– The paper reports a quantitative study of 323 managers working in manufacturing and pharmaceutical organisations based in western India. Drawing from social exchange theory, this paper tests the mediating role of trust in the justice-engagement relationship. The paper also investigates the effect of work engagement on employees' innovative work behaviour.
Findings
– Results suggest that procedural justice, interactional justice and psychological contract fulfilment are positively related to work engagement with trust as the mediating element. Engagement significantly influences employees' innovative work behaviour
Research limitations/implications
– The data were collected cross-sectionally, which means that causal inferences must be made with caution. Moreover, the data were collected from a single source. Nevertheless, the findings have implications for contemporary leadership and organisational psychology research and practice in a novel geographic context.
Originality/value
– This study is one of the rare attempts to examine the influence of three justice variables and trust on work engagement. The study also contributes in terms of its context. With an increasing number of multinationals starting operations in India, an understanding of employee motivation has become an important concern. This research examines engagement levels of Indian managerial employees.
The knowledge on the mode of action, biocompatibility and ecological tolerance of silver nanoparticles (AgNPs) is gradually accumulating over the years with contradictory findings. Most of the ...studies indicated the toxic impact of AgNPs on plant growth and development, where induction of oxidative stress was considered to be one of the causal factors. The present study demonstrates the phytostimulatory effect of bio-synthesized silver nanoparticles (AgNPs) during seed germination and seedling growth of rice (Oryza sativa L., cv. Swarna) under in vitro condition. All the tested concentrations of AgNPs (10, 20, 40 ppm) promote both the shoot and root growth which was evident from the increased length and biomass of the seedlings. Exposure to AgNPs also significantly increased the chlorophyll a and carotenoid contents. The content and the pattern of distribution of phenolic metabolites among the different treatments are indicative of non-toxic impact of AgNP mimicking mild or no stress to the seedlings. Growth stimulation of rice seedlings by AgNPs was further supported by a low level of reactive oxygen species (ROS) concomitant with decreased amount of lipid peroxidation and H2O2 content, compared to control. In order to unravel the stimulatory impact of AgNPs on rice seedling growth, the present study also describes the AgNPs induced changes in antioxidative enzyme activity and related gene expression levels. Elevated levels of catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR) activities were recorded in all the AgNPs treated seedlings with improved growth. The activity of superoxide dismutase (SOD) was not significantly altered at low concentration of AgNPs. It appears that enzymes of ascorbate cycle, APX and GR are more active in ensuring protection against oxidative damage than SOD. There was significant up-regulation of CAT and APX gene expressions in seedlings exposed to AgNPs, whereas the expression level of CuZnSOD gene was decreased gradually with an increase in the concentration of AgNPs. The antioxidant enzyme activities and gene expression patterns coupled with the levels of H2O2 and lipid peroxidation indicates that the efficiency of redox reactions was increased in the presence of AgNPs and that accelerates the seedling growth.
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•Bio-synthesized silver nanoparticles (AgNPs) promoted the growth of rice seedlings.•A low level of ROS with decreased amount of lipid peroxidation and H2O2 content was found in AgNP treated seedlings.•Exposure to AgNPs elevated the activities of CAT, APX and GR.•CAT and APX genes were up-regulated, whereas expression of SOD gene was decreased in seedlings exposed to AgNPs.•An efficient redox balance induced by AgNPs may account for the improved growth of rice seedlings.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
This review summarises the research work carried out in the field of carbon nanotube (CNT) metal matrix composites (MMCs). Much research has been undertaken in utilising CNTs as reinforcement for ...composite material. However, CNT-reinforced MMCs have received the least attention. These composites are being projected for use in structural applications for their high specific strength as well as functional materials for their exciting thermal and electrical characteristics. The present review focuses on the critical issues of CNT-reinforced MMCs that include processing techniques, nanotube dispersion, interface, strengthening mechanisms and mechanical properties. Processing techniques used for synthesis of the composites have been critically reviewed with an objective to achieve homogeneous distribution of carbon nanotubes in the matrix. The mechanical property improvements achieved by addition of CNTs in various metal matrix systems are summarised. The factors determining strengthening achieved by CNT reinforcement are elucidated as are the structural and chemical stability of CNTs in different metal matrixes and the importance of the CNT/metal interface has been reviewed. The importance of CNT dispersion and its quantification is highlighted. Carbon nanotube reinforced MMCs as functional materials are summarised. Future work that needs attention is addressed.
Postoperative pain is the dominating complaint and the primary reason for prolonged convalescence after laparoscopic cholecystectomy. We have evaluated the efficacy of a single preoperative dose of ...pregabalin for attenuating postoperative pain and fentanyl consumption after laparoscopic cholecystectomy.
Sixty adults (16–60 yr), ASA physical status I and II, of either sex undergoing elective laparoscopic cholecystectomy were included in this prospective, randomized placebo controlled, double-blind study. Subjects were divided into two groups of 30 each to receive either a matching placebo or pregabalin 150 mg, administered orally 1 h before surgery. Postoperative pain (static and dynamic) was assessed by a 100 mm visual analogue scale, where 0, no pain; 100, worst imaginable pain. Subjects received patient-controlled i.v. fentanyl analgesia during the postoperative period. Results were analysed by Student's t-test, χ2 test, Mann–Whitney U-test, and Fisher's exact test.
Postoperative pain (static and dynamic) and postoperative patient-controlled fentanyl consumption were reduced in the pregabalin group compared with the placebo group (P<0.05). Side-effects were similar in both groups.
A single preoperative oral dose of pregabalin 150 mg is an effective method for reducing postoperative pain and fentanyl consumption in patients undergoing laparoscopic cholecystectomy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Summary
Reactive oxygen species (ROS) have been extensively studied as a cause of male infertility. Excessive levels of ROS coupled with a deficiency in antioxidants can lead to oxidative stress ...(OS), which in turn can lead to nuclear and mitochondrial DNA damage, telomere shortening, epigenetic alterations and Y chromosomal microdeletions. In this review, we discuss how OS induces DNA damage and the types of DNA damage that can occur. We also briefly touch on the clinical consequences of OS‐induced DNA damage.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
A two-dimensional, tetragonal porous metal organic framework {Zn 2 (TBIB) 2 (HTCPB) 2 ·9DMF·19H 2 O} n (1) has been synthesized under hydrothermal conditions by employing ...1,3,5-tri(1H-benzodimidazol-1-yl)benzene (TBIB) and 1,3,5-tris(4′-carboxyphenyl-)benzene (H3TCPB). But noncovalent supramolecular interactions between the layers make this framework three-dimensional, generating porosity in one dimension. Flexibility arises due to the presence of two types of large linkers wherein some functional groups of the ligands are not coordinated with the metal ion. Desolvated polymer shows moderate CO2 uptake (65 cm3 g–1 at 195 K and 1 bar) at low temperature and pressure. Compound 1 acts as a highly efficient heterogeneous catalyst toward the formation of cyclic carbonate through cycloaddition of CO2 as well as toward the synthesis of quinoline derivatives by the Friedländer reaction. The presence of the free −COOH, −CO groups and uncoordinated −N atoms on the wall of the pores makes this framework an excellent candidate for the catalytic reactions without activation of the compound.
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IJS, KILJ, NUK, PNG, UL, UM
The goal of decentralized optimization over a network is to optimize a global objective formed by a sum of local (possibly nonsmooth) convex functions using only local computation and communication. ...It arises in various application domains, including distributed tracking and localization, multi-agent coordination, estimation in sensor networks, and large-scale machine learning. We develop and analyze distributed algorithms based on dual subgradient averaging, and we provide sharp bounds on their convergence rates as a function of the network size and topology. Our analysis allows us to clearly separate the convergence of the optimization algorithm itself and the effects of communication dependent on the network structure. We show that the number of iterations required by our algorithm scales inversely in the spectral gap of the network, and confirm this prediction's sharpness both by theoretical lower bounds and simulations for various networks. Our approach includes the cases of deterministic optimization and communication, as well as problems with stochastic optimization and/or communication.
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