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Physical Co-location: an intersection of problem-solving and vicarious learning
Scholars have examined Revans' problem-solving praxeology in many contexts but have not fully explored the concept in the case of physical co-location. Hence, we focussed on investigating Revans' conceptualisation in a co-located context by paying particular attention to the different forms of learning' that emerged from it. The research setting for this study involved two coworking spaces in Bangalore, India, whose constituents were co-located start-ups and established enterprises. Held from January to March 2020, the study involved conducting exploratory, semi-structured interviews with twelve firms. The findings suggested that in a co-located environment, a) firms learnt vicariously' from a rich, external knowledge base during the enquiry-led Alpha phase b) firms learnt experientially', through learning by doing and reflecting in the implementation-focussed Beta phase c) firms learnt through the process of emergence that resulted from personal reflection and team interaction, in the revelatory Gamma phase. This study lends a novel direction in acknowledging that vicarious learning, that is, learning through the experience of others, serves as a starting point for problem-solving in a co-located context. We demonstrate that firms gain familiarity with the problem through vicarious sources, that is, from those experienced co-located firms who had journeyed on a similar path. 2021 Informa UK Limited, trading as Taylor & Francis Group. -
Physical fitness recommender framework for thyroid patients using restricted boltzmann machines
These days, people can easily acquire the information from online sources. Individuals are generally using recommendation services before buying products considering the availability of online. Recommendation systems propose the relevant services or products to users. But sometimes people face issues while retrieving health related information from the recommender systems. A focus on keeping people healthy is one way to address the serious societal concern of healthcare domain. A health-based physical recommender system suggests workout plans for users using their activity level and health condition. A personalized approach is the most effective solution for the fitnessbased recommender framework based on user's desired characteristics. This article presents a personalized fitness recommender system for thyroid patients. The proposed fitness recommender model integrates the user's data like personal and health profile, preferences, calorie intake, and activity level. The proposed hybrid model is built using Restricted Boltzmann Machines (RBM) integrating content based and matrix factorization techniques. The results of experiments prove that the proposed hybrid model outperforms than content based, pure RBM and matrix factorization recommendation techniques. The current proposal achieves the personalization approach by incorporating user's thyroid health condition and exercise preferences in recommendation process. The recommended result of hybrid RBM method is revised based on user's new preferences. 2020, Intelligent Network and Systems Society. -
Physical framework for a counselling environment in India: Thematic analysis of counsellors' perceptions
The influence of the physical environment on the counselling process is an inevitable part of a counselling session. However, there is little insight in Indian research into the desirable elements of the physical environment of the counselling room that helps facilitate a counselling session. Interviews were conducted with 10 professional counsellors in India. Thematic analysis of the databrought out various Basic and Organising themes under the following three Global themes: (a) Elements of the physical framework; (b) Counsellor's perspectives about the physical framework in counselling; and (c) Motivation to build a framework. The findings show how counsellors can systematise the physical framework to help construct the counselling session effectively. 2020 British Association for Counselling and Psychotherapy -
Physical layer impairment-aware routing and wavelength assignment (PLI-RWA) strategy for mixed line rate (MLR) wavelength division multiplexed (WDM) optical networks
The ever increasing global Internet traffic is resulting in a serious upgrade of the current optical networks' capacity. The legacy infrastructure can be enhanced not only by increasing the capacity, but also by adopting advance modulation formats, having increased spectral efficiency at higher data rate. In a mixed-line-rate (MLR) optical network, different line rates, on different wavelengths, can coexist on the same fiber. Further, studies have shown that migration to data rates higher than 10Gbps requires implementation of phase modulation schemes. However, the co-existing On-Off Keying (OOK) channels cause critical physical layer impairments (PLIs) to the phase modulated channels, mainly due to cross-phase modulation (XPM), which in turn limits the network's performance. In order to mitigate this effect, a more sophisticated PLI-Routing and Wavelength Assignment (PLI-RWA) scheme needs to be adopted. In this work, we investigate the critical impairment for each data rate and the way it affects the quality of transmission (QoT). We propose a novel PLI-RWA algorithm for MLR optical networks. The proposed algorithm is compared through simulations with the existing shortest path and minimum hop routing schemes. 2015 IEEE -
Physical properties of vapour grown indium monotelluride platelets
Indium monotelluride (InTe) crystals were grown from vapour phase under different temperature gradients by employing physical vapour deposition (PVD) method. The morphology of these crystals such as whiskers, needles, platelets etc., strongly depends on the temperature distribution in the horizontal dual zone furnace. InTe platelets were deposited by setting the temperature of the charge (TC) and growth (TS) zones at 1073 K and 773 K (?T=300 K), respectively, for different growth periods (24 h, 48 h, 72 h and 96 h). The surface growth features have been analyzed by scanning electron microscopes, which indicate layer growth mechanism for all the crystals. Various crystals grown under ?T=200 K and 300 K (retaining TS invariant) were examined by X-ray diffraction and elemental analysis. InTe samples exhibited consistent lattice parameters, density and atomic percentage, establishing stoichiometry and chemical homogeneity. The results obtained for Seebeck coefficient, electrical conductivity, power factor, dislocation density and microhardness are found to be reproducible as well. The vapour deposited InTe platelets are mechanically stable and possess high value of TEP, which ensure their practical application in thermoelectric power generation. 2014 Elsevier B.V. -
Physical properties of vapour grown indium monotelluride platelets /
Journal Of Crystal Growth, Vol.415, pp.81-87, ISSN No: 0022-0248. -
Physical Unclonable Function and OAuth 2.0 Based Secure Authentication Scheme for Internet of Medical Things
With ubiquitous computing and penetration of high-speed data networks, the Internet of Medical Things (IoMT) has found widespread application. Digital healthcare helps medical professionals monitor patients and provide services remotely. With the increased adoption of IoMT comes an increased risk profile. Private and confidential medical data is gathered across various IoMT devices and transmitted to medical servers. Privacy breach or unauthorized access to personal medical data has far-reaching consequences. However, heterogeneity, limited computational resources, and lack of standardization in authentication schemes prevent a robust IoMT security framework. This paper introduces a secure lightweight authentication and authorization scheme. The use of the Physical Unclonable Function (PUF) reduces pressure on computational resources and establishes the authenticity of the IoMT. The use of OAuth 2.0 open standard for authorization allows interoperability between different vendors. The resilience of the model to impersonation and replay attacks is analyzed. 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. -
Physical vapor deposition and enhancement of optoelectronic properties of SnSe2 platelets
Stoichiometric tin diselenide (SnSe2) platelet crystals have been prepared by physical vapor deposition (PVD) method under high vacuum (~ 106mbar) using a homemade dual-zone furnace. The driving force for growth was optimized in terms of temperature difference (?T = 270 to 420C) of nutrient and growth zones. Good quality platelets, devoid of any screw dislocations, hillocks, defects etc. were crystallized at ?T = 400C by layer growth mode as per the 3D optical profiler and electron microscopic images. Rietveld refinement of the PXRD data using FullProf suite software justified hexagonal crystal structure with a = 3.811 c = 6.137and the computed density (5.967g/cm3) is in agreement with that obtained based on Archimedes principle. Chemical homogeneity of these samples was probed by EDAX, XPS and Raman analysis. The thermal and mechanical behavior was investigated by TGA as well as Vickers microhardness experiments. The values of optical band gap (1.20eV), absorption coefficient (7.25 105cm?1), resistivity (2.70 ? cm), mobility (32.70 cm2V?1s?1) and carrier concentration (3.08 1016cm?3) have been evaluated using UVVis-NIR, photoluminescence, and Hall effect measurements. The enhancement of optoelectronic parameters of the as-grown SnSe2 platelets free of polytypism, throws light on their potential for photovoltaic applications. 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
Physicochemical Properties, Chemical Composition and Antioxidant Activities of Artemisia pallens Wall. Seed Oil
The physico-chemical characteristics, fatty acid composition and antioxidant capacities of Artemisia pallens seed oil were determined in this study. The moisture, oil content, fatty acid, iodine, peroxide, saponification values, specific gravity and refractive index were 4.13 %, 25.53 %, 1.84 % (as oleic acid), 138.14 (mg/ l00 g), 10.20 (meqO2/kg oil), 194.21 (mg KOH/g oil) 0.92 and 1.47, respectively. Linoleic acid (C18:2, 79.963 %), oleic acid (C18:1, 9.40 %) and palmitic acid (C16:0, 7.89 %) were the major fatty acids. High amount of total unsaturated fatty acids (89.74 %) make it highly desirable as a source of nutrition. The antioxidant capacities of the seed oil showed that it can be a source for natural antioxidants and functional food. The results of the present study showed that the A. pallens is a promising seed oil crop and can be used for making of soaps, shampoos and alkyd resins. Further, the high amount of polyunsaturated fatty acid i.e. linoleic acid makes it desirable in terms of nutrition. 2019, 2019 Har Krishan Bhalla & Sons. -
Physics of Gravitational Waves: Sources and Detection Methods
[No abstract available] -
Phyto- and zoomass-derived nanostructured carbon as efficient catalysts for oxygen reduction reaction in fuel cells: a review
Abstract: The oxygen reduction reaction (ORR) plays a pivotal role in several energy storage and conversion technologies, including metal-air batteries, microbial fuel cells, and low-temperature hydrogen and alcohol fuel cells. Fuel cells, in particular, have gained significant traction as a feasible alternative energy source due to their efficiency, cleanliness, adaptability, and ability to reuse exhaust heat. However, the complex nature of ORR requires highly efficient electrocatalysts for optimal fuel cell performance. While Pt-based electrocatalysts are widely regarded as the most suitable for both the cathode and anode in fuel cells, their high cost, scarcity, and susceptibility to fuel crossover have driven the search for alternative ORR catalysts. In this context, carbon materials have emerged as promising candidates due to their low cost, long-term stability, and strong electrocatalytic activity. Recent advancements in biomass-derived carbon nanostructures align with the global push for sustainable energy and a pollution-free environment. This review examines carbon structures derived from the carbonization of plant and animal biomass and evaluates their performance as noble metal supports, non-noble metal electrocatalysts, and metal-free electrocatalysts for ORR. Graphical abstract: (Figure presented.) The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024. -
Phytochemical Analysis and Antibacterial Potential of Stevia rebaudiana (Bertoni, 1899) Leaf Extracts against Aeromonas Species: Influence of Extraction Methods and Solvents in Aquaculture Applications
Recent studies have explored Stevia rebaudiana Bertoni leaf extracts for their antibacterial potential and phytochemical content. However, the impact of extraction methods and solvents on aquaculture bacteria remains understudied. This research aimed to evaluate the antibacterial, radical scavenging, and phytochemical properties of S. rebaudiana extracts against Aeromonas species. Dried S. rebaudiana leaves were extracted using methanol (Mt) and ethanol (Et) through Soxhlet and maceration methods (SMt, SEt, MMt and MEt respectively). Soxhlet extraction yielded higher amounts (36.29% for Mt, 23.87% for Et) compared to maceration. Phytochemical analysis identified phenolics, flavonoids, alkaloids, saponin, tannin, and steroids in all extracts. Notably, MEt had elevated phenolic and flavonoid content, while SEt contained more tannins. MEt exhibited the strongest antioxidant activity (IC50 = 67.95g/mL), aligning with its high phenolic and flavonoid levels. In antibacterial assays against Aeromonas strains, ethanol extract showed the largest zone of inhibition (ZOI) of 16.67mm for A. salmonicida, followed by methanol extract (15mm) at 250 mg/mL, using maceration and Soxhlet methods, respectively. However, none of the extracts displayed activity against A. hydrophila. This suggests that cold maceration is a cost-effective method that preserves heat-sensitive secondary metabolites within a shorter extraction time. In conclusion, this study highlights the significance of extraction techniques and solvents in obtaining potent antibacterial and antioxidant extracts from S. rebaudiana leaves. The findings emphasize the potential of these extracts in aquaculture practices and open avenues for further research in utilizing natural compounds for sustainable aquaculture strategies. The Author(s) 2023. -
Phytochemical analysis and antioxidant activities of Artemisia stelleriana Besser leaf extracts
The present study aims to report the proximate and mineral composition, phenolic contents, and antioxidant potential of Artemisia stelleriana leaves. The leaf extracts were prepared using various solvents like distilled water, methanol, ethanol and acetone and analyzed for their phenolic and flavo-noid contents and antioxidant activity. The methanolic extracts showed the highest total phenolic and flavonoid contents (10.09 0.24 mg GAE/g and 225.04 0.38 mg QE/g respectively). The methanolic extracts showed signifi-cantly higher 1,1-Diphenyl-2-picrylhydrazyl radical scavenging assay (DPPH-RSA), Reducing power assay and total antioxidant capacity compared to distilled water, ethanol and acetone extracts. Gas Chromatography-Mass Spectroscopy revealed that the methanolic extracts of leaves to be a good source of bioactive compounds like 2,4-di-tert-butylphenol (2,4-DTBP), neo-phytadiene, octacosane and eucalyptol. 2022 Horizon e-Publishing Group. All rights reserved. -
Phytochemical analysis and antioxidant activity of leaf extracts of some selected plants of the family acanthaceae
The present era of scientific research has witnessed an enumerable amount of evidences to showcase the immense potential of medicinal plants. In the present investigation, the phytochemical analysis of Phlogacanthus pubinervius T. Anderson., Adhatoda vasica (L.) Nees,Phlogacanthus thyrsiflorus Nees, Phlogacanthus curviflorus (Wall.) Nees, and Ruellia tuberosa L. was carried out for the different plants extracted with methanol. Analysis was carried out to estimate the quantity of phenols, carbohydrates, tannins, flavonoids and proteins. The antioxidant property of these plants were analysed using DPPH method. The concentration of the plant samples required to decrease the DPPH concentration by 50% was calculated by interpolation from linear regression analysis and denoted IC50 value (g/ml). The qualitative analysis showed the presence of alkaloids, tannins, saponins, proteins, carbohydrate and phenols in all the sample extracts. The highest amount of tannins and phenols was observed in P. thyrsiflorus. P. pubinervius (77.83%), A. vasica (74.81%), P. curviflorus (94.20%), and R. tuberosa (70.78%) which showed highest antioxidant activity of DPPH-scavenging at 150 g/ml of methanol extract. The high percent of scavenging activities of those plants add value to their medicinal properties. The presence of the high amount of phytochemical compounds suggests that the plants have high amount of medicinal compounds and can be extensively used to extract the natural compounds. Kripasana & Xavier (2020). This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited (https://creativecommons.org/licenses/by/4.0/). -
Phytochemical analysis, anti-oxidant properties and pass assisted prediction of biological activity of sargassum wightti j. Agardh, sargassum ilicifolium (turner) C. Agardh and sargassum lanceolatum J. Agardh
The present study was carried out to determine the phytoconstituents and anti-oxidant properties present in the Sargassum wightti, Sargassum ilicifolium and Sargassum lanceolatum using GC-MS analysis and predict the biological activity by PASS prediction. Gas chromatography/mass spectrometry (GC/MS) analysis was performed on Shimadzu GC interfaced with mass spectrometry using SH-RxiTM-5Sil (Shimadzu) column. The spectra of the phytoconstituents were obtained by the PASS version (http:// www.way2drug.com/passonline). The prediction was based on an analysis of the structure-activity relationships (SAR) in the training set containing information on the structure. GC-MS analysis revealed 39 compounds in S. wightti, 60 compounds in S. lanceolatum and 15 compounds in S. ilicifolium. Common compounds found in these three Sargassum species were 1s,4R,7R,11R-1,3,4,7-Tetramethyltricyclo [5.3.1.0(4,11)] undec-2-en-8-one,2,4-Di-tert-butyl phenol, 1-Decanol, 2-hexyl, Hexatriacontyl-trifluoroacetate, Nonyltetradecyl ether, Neophytadiene, Hexadecane. Sargassum species are rich in anti-oxidant, anti-inflammatory, anti-bacterial and anti-viral properties. The present study proved the presence of bioactive compounds and phytochemical compounds in three species of Sargassum available in Indian coastal regions. 2021, Agri Bio Research Publishers. All rights reserved. -
Phytochemical Composition, Bioactive Compounds, and Antioxidant Properties of Different Parts of Andrographis macrobotrys Nees
Andrographis macrobotrys Nees is an ethnomedicinal plant belonging to the family Acanthaceae, distributed in the moist deciduous and semi-evergreen forests of the southern Western Ghats of India. The objective of this research was to determine the phytochemical composition and bioactive chemical components using gas chromatography and mass spectrometry (GC-MS) and to check the antioxidant potential of the plant part extracts. A. macrobotrys roots, stems, and leaves were obtained from the species natural habitat in the Western Ghats, India. The bioactive compounds were extracted using a Soxhlet extractor at 5560 C for 8 h in methanol. Identification analysis of A. macrobotrys bioactive compound was performed using GC-MS. Quantitative estimation of phytochemicals was carried out, and the antioxidant capacity of the plant extracts was determined by 2,2?-diphenyl-1-picrylhydrazyl radical scavenging (DPPH) and ferric reducing assays (FRAP). A. macrobotrys has a higher concentration of phenolics in its stem extract than in its root or leaf extracts (124.28 mg and 73.01 mg, respectively), according to spectrophotometric measurements. GC-MS analysis revealed the presence of phytochemicals such as azulene, 2,4-di-tert-butylphenol, benzoic acid, 4-ethoxy-ethyl ester, eicosane, 3-heptadecanol, isopropyl myristate, hexadecanoic acid methyl ester, hexadecanoic acid, 1-butyl-cyclohexanol, 9,12-octadecadienoic acid, alpha-monostearin, and 5-hydroxy-7,8-dimethoxyflavone belonging to various classes of flavonoids, terpenoids, phenolics, fatty acids, and aromatic compounds. Significant bioactive phytochemicals include 2,4-di-tert-butylphenol, 2-methoxy-4-vinylphenol, 5-hydroxy-7,8-dimethoxyflavone, azulene, salvigenin, squalene, and tetrapentacontane. In addition, the antioxidant capability of each of the three extracts was assessed. The stem extract demonstrated impressive DPPH scavenging and ferric reduction activities, with EC50 values of 79 mg/mL and 0.537 0.02 OD at 0.2 mg/mL, respectively. The results demonstrated the importance of A. macrobotrys as a source of medicine and antioxidants. 2023 by the authors. -
Phytochemical fingerprinting and evaluation of in silico anti-thrombotic properties of Justicia adhatoda L. and Cordia dichotoma Frost
The study aimed to characterize hydro-methanolic (25%) extracts of Justicia adhatoda L. (stem and flower) and Cordia dichotoma Frost. (Stem and fruit) and evaluate the in silico thrombolytic properties of the major phytocompounds present in the plants. In the preliminary fluorescence imaging through treatment by different reagents, both plants were found to be pharmacologically active. Further qualitative screening of phytochemicals, spectroscopy-based techniques, namely, UV-Vis Spectroscopy and FTIR, revealed various classes of compounds such as polyacetylenes, aglycones, quercetin, anthocyanins, anthraquinones, alkaloids, chalcones and aurones, flavanols, carotenoids, and flavanones. Further, by the application of Thin Layer Chromatography, phenols and flavonoids, namely Catechol, Kaempferol, Quercetin, and Lutein, along with other compounds like Chlorophyll b, Glutamic Acid, and Tryptophan were identified from the extracts. Finally, in the molecular docking study, three compounds, Datiscoside and Robinin of C. dichotoma and Daucosterol of J. adhatoda showed high binding energies (-10.224,-9.547 and-9.262 kcal mol-1 respectively) towards the G-protein coupled thrombotic platelet aggregation receptor P2Y1 when compared to that of the control MRS2500 (-7.148 kcal mol-1). Articles by the authors; Licensee SMTCT, Cluj-Napoca, Romania. -
Phytochemical, pharmacological and tissue culture studies of some important species of the genus Barleria L. (Acanthaceae) - a review
Ayurvedic sciences helped the early humans to overcome chronic dangerous diseases. There are thousands of varieties of herbs and medicinal plants used to overcome such dreadful diseases. The genus Barleria L. belongs to family Acanthaceae, a medicinally significant group of plants having diversified phytochemicals used for different pharmacological properties. It has been utilized since ancient times for medicinal purposes. It has many plant secondary metabolites such as terpenes, flavonoids, lignins, alkaloids, particularly the iridoid glycosides. The secondary metabolites extracted from Barleria spp. show potential pharmacological activities viz., anti-microbial, anti-inflammatory, anti-oxidant, anti-fertility, anti-arthritic and anti-ulcer activity. In view of these, present review is focused on the phytochemistry, pharmacology and tissue culture studies of some of the important species of the genus Barleria L. Sudheer & Praveen (2021). -
Phytochemicals as potential drug candidates for targeting SARS CoV 2 proteins, an in silico study
Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a member of the family Coronaviridae, and the world is currently witnessing a global pandemic outbreak of this viral disease called COVID-19. With no specific treatment regime, this disease is now a serious threat to humanity and claiming several lives daily. In this work, we selected 24 phytochemicals for an in silico docking study as candidate drugs, targeting four essential proteins of SARS-CoV-2 namely Spike glycoprotein (PDB id 5WRG), Nsp9 RNA binding protein (PDB id 6W4B), Main Protease (PDB id 6Y84), and RNA dependent RNA Polymerase (PDB id 6M71). After statistical validation, the results indicated that a total of 11 phytochemicals divided into two clusters might be used as potential drug candidates against SARS-CoV-2. 2021, Indian Virological Society. -
Phytochemicals as weapons against drug resistance
Phytochemicals are plant-based products with high medicinal value. These metabolites effectively target disease-causing microbes. Drug-resistant pathogens have developed mechanisms to sustain themselves even with inhibitors. Drug resistance has emerged as a global giant, causing all available treatment options to fail. The solution to this problem is in the phytochemicals of plants with antibacterial and drug resistance modulation properties. Phytochemicals might be able to get rid of efflux pumps, drug-modulating enzymes, resistance genes, quorum sensing, and biofilm, all of which cause pathogens to be resistant to drugs. Moreover, anti-obesogenic and cardioprotective properties are also observed in phytochemicals. Additionally, studies show the success of phytochemical-based nanoparticles in drug resistance regulation. This review emphasizes phytochemicals' different mechanisms of action and their derivatives in curbing drug-resistant pathogens and cancer cells. 2023 The Author(s)