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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 characterization of fluoride solid electrolyte PbSnF4 synthesized via sonochemical reaction
Demand for batteries with enhanced energy density and improved thermal safety is a key focus for researchers striving to build a sustainable environment. As fluoride ion batteries (FIB) are expected to exhibit high energy density and exceptional thermal stability, research activities are focused on identifying fluoride ion-conducting electrolytes. Among the various fluoride ion conductors, PbSnF4, renowned for its superior ionic conductivity, is typically synthesized via mechanochemical reaction. In the present work, PbSnF4 was synthesized via an acoustic cavitation-driven sonochemical reaction. This novel synthesis route has reduced the duration of the synthesis process to a few minutes compared with several hours for the mechanochemical reaction. The structural, morphological, and ionic transport properties are investigated. The ionic conductivity of the resulting orthorhombic PbSnF4 is evaluated to be 4.5 10?4 S/cm at RT. The contribution of fluoride ions to the total ionic conductivity is estimated via the DC polarization technique as 0.92. The electrochemical stability window (ESW) is measured through cyclic voltammetry (CV) as 0.7 V with PbF2/PbSnF4/SS cell configuration. 2025 -
Physicochemical Modifications on Fibrous Substrates for Sensing and Separation Applications
Fibers are forms of matter characterized by flexibility, fineness, and a high length-tothickness ratio, embodying properties such as large surface-area-to-volume ratio, newlinecontinuity, flexibility in surface functionalities, superior mechanical performances, ability to absorb dye and moisture, etc. Fibers can be transformed into coils, yarns, or fabrics by twisting or overlapping, resulting in fibrous substrates that are self-standing, flexible, and possessing excellent mechanical properties and large specific surface areas. The porosity, functionality, hydrophobic and hydrophilic properties, and functional characteristics for desirable applications can be achieved by various modifications of the fiber substrates. Physical (e.g., composite material blending, coating) and chemical (e.g., surface hydrolysis, chemical crosslinking) methods have been used to modify fiber substrates. These physicochemical modifications render the newlinefibers suitable for specialized applications such as food packaging, food spoilage newlinedetection, and wastewater treatment. Existing modification strategies for preparing indicators for food quality monitoring are newlinenot user-friendly, equipment-free, and cannot be used without training and expertise. Newer approaches to the modification of fiber substrates are thus essential to provide newlinesuitable indicators for household settings. There is also a requirement for straightforward methods that quantifies the color to indicate the quality of food and newlinefacilitates its use in domestic environments without personal expertise or laboratory newlinesetup. In this regard, we focused on developing simple physicochemical modifications of fibrous substrates for food-quality monitoring. In our first work, natural jute fiber was subjected to delignification to incorporate pH-sensitive anthocyanins. This indicator was used as a point-of-care colorimetric indicator for monitoring fish quality. -
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. -
Phyto-Electrochemical Mapping of Indian Cappers: Redox Mediator Application on Mesoporous Carbon Based Electrodes
Indian Cappers (IC), often known for its wide range of applications as a medicinal plant, is an essential spice with phenolic phytochemical attributes. These are plausibly electrochemically redox active in nature. The redox moiety of phytochemicals can be exploited as a green route electron-transfer mediator, rather than conventional chemical redox mediators. Herein, mesoporous carbon-assisted electrochemical redox mapping of a phytochemical using IC plant is reported. A well-defined redox peak for IC-redox with E0 = 0.2 V is observed with a surface excess (?) value of 44.8 109 mol cm?2. Physico-chemical characterization is carried out to provide a detailed analysis of IC redox-based constituents. Furthermore, the fabricated IC sensor is used for the electrocatalytic oxidation of Ascorbic acid (AA) as a model system for preparing electrochemical sensors. The prepared sensor gave a notable oxidation peak for AA at E?= 220 mV with a sensitivity value of 0.0385 ?A/?M in the range of 0?1000 ?M. This work is a preliminary experiment for on-site testing of ascorbic acid in blood serum samples as a point of care testing. Additionally, the Cappers showed appreciable antibacterial activity against both Gram-positive and Gram-negative strains, producing clear inhibition zones even without the use of antibiotics. 2025 The Electrochemical Society (ECS). Published on behalf of ECS by IOP Publishing Limited. All rights, including for text and data mining, AI training, and similar technologies, are reserved. -
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 characterization by GC-MS and in vitro evaluation of antioxidant potential of Walsura piscidia Roxb. leaves extract
Walsura piscidia Roxb. (Family: Meliaceae) is currently known for rich sources of bioactive compounds with growing multiple therapeutic and medicinal importance. The main objectives of this study were to characterize the phytochemical profile of the leaves of W. piscidia by Gas Chromatography-Mass Spectrometry (GC-MS), followed by the evaluation of its antioxidant potential by quantifying the amounts of phenols and flavonoids present within the extracts, through the existing methods of detection. The extractive yield calculated after Soxhlet extraction was seen to be higher for the ethanolic extract with a value of 21.9 %, followed by the methanolic extracts (21.06 %) and the qualitative phytochemical tests gave similar classes of phytochemicals like triterpenoids, phenolic compounds and tannins in the methanolic and ethanolic extracts. The total phenolic content was seen to be higher in the ethanolic extract with a value of 26.192 0.401 mg GAE/g and the total flavonoid content was seen to be higher in the methanolic extract with a value of 42.972 0.214 mg QE/g. The methanolic extract showed promising results in the antioxidant assays with a significantly low IC50 value in DPPH assay and high ferric reducing power in ferric reducing antioxidant power (FRAP) assay. The GC-MS chromatograms showed almost similar compounds for both the methanolic and ethanolic leaf extracts, some important ones being n-Hexadecanoic acid, stigmasterol, campesterol, 5-hydroxymethyl furfural, etc, displaying properties of interest like antioxidant, anti-inflammatory, anti-microbial, etc. This work contributes to our better understanding of the medicinal properties of the leaves of W. piscidia and has also provided a strong scientific basis to the traditional usage claims of this tree. The Author(s). -
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.