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Towards an Epistemology of Reading: Defining the Process of Reading in Modern Terms
The chaotic space caused by information explosion in present times has made the process and purpose of reading to be always questioned. Technological advancement has made reading appear as a mere mockery at the very outset. But the world still prioritizes knowledge that is acquired through observation, valuation and interpretation. At the time of Big Data, there still persists a sense of agency to define a given information as episteme. The present essay emphasizes on looking at reading as a modern phenomenon by presupposing the epistemological presence at the centre of any rational pursuit. Based on the Kantian precepts on enlightenment, the paper attempts to understand this presence of knowledge by delving into the major disciplines of modern philosophy that help in observing, valuing and interpreting the act of reading in present times. More than laying terms for defining the text within the modern space, the study essentializes reading in a virtually driven algorithmic world. AesthetixMS 2021 -
Effects of dark matter in star formation
The standard model for the formation of structure assumes that there existed small fluctuations in the early universe that grew due to gravitational instability. The origins of these fluctuations are as yet unclear. In this work we propose the role of dark matter in providing the seed for star formation in the early universe. Very recent observations also support the role of dark matter in the formation of these first stars. With this we set observable constraints on luminosities, temperatures, and lifetimes of these early stars with an admixture of dark matter. 2019, Springer Nature B.V. -
Alternate models to dark energy
One of the unresolved questions currently in cosmology is that of the non-linear accelerated expansion of the universe. This has been attributed to the so called Dark Energy (DE). The accelerated expansion of the universe is deduced from measurements of Type Ia supernovae. Here we propose alternate models to account for the Type Ia supernovae measurements without invoking dark energy. 2017 COSPAR -
Dark matter, dark energy, and alternate models: A review
The nature of dark matter (DM) and dark energy (DE) which is supposed to constitute about 95% of the energy density of the universe is still a mystery. There is no shortage of ideas regarding the nature of both. While some candidates for DM are clearly ruled out, there is still a plethora of viable particles that fit the bill. In the context of DE, while current observations favour a cosmological constant picture, there are other competing models that are equally likely. This paper reviews the different possible candidates for DM including exotic candidates and their possible detection. This review also covers the different models for DE and the possibility of unified models for DM and DE. Keeping in mind the negative results in some of the ongoing DM detection experiments, here we also review the possible alternatives to both DM and DE (such as MOND and modifications of general relativity) and possible means of observationally distinguishing between the alternatives. 2017 COSPAR -
Gammaless gamma-ray bursts?
One of the possible resolutions of the compactness problem in gamma-ray bursts (GRBs) is by invoking the Lorentz factors associated with the relativistic bulk motion. This model applies to GRBs where sufficient energy is converted to accelerate the ejected matter to relativistic speeds. In some situations, this may not be a possible mechanism, and as a result, the gamma rays are trapped in the region. In this work, we look at such possible scenarios and where the neutrino pair production process can dominate. As a result, the neutrinos can escape freely. This could give rise to a scenario where the release of neutrinos precedes the gamma-ray emission that is much attenuated. This model can thus possibly explain why fewer GRBs are observed than what is expected. 2023, Indian Association for the Cultivation of Science. -
Synthetic biology for sustainable food ingredients production: recent trends
Problems with food security result from increased population, global warming, and decrease in cultivable land. With the advancements in synthetic biology, microbial synthesis of food is considered to be an efficient alternate approach that could permit quick food biosynthesis in an eco-friendly method. Furthermore, synthetic biology can be assumed to the synthesis of healthy or specially designed food components like proteins, lipids, amino acids and vitamins and widen the consumption of feedstocks, thus offering possible resolutions to high-quality food synthesis. This review describes the impact of synthetic biology for the microbial synthesis of various food ingredients production. 2022, Jiangnan University. -
Integrated biorefinery development for pomegranate peel: Prospects for the production of fuel, chemicals and bioactive molecules
Current experimental evidence has revealed that pomegranate peel is a significant source of essential bio compounds, and many of them can be transformed into valorized products. Pomegranate peel can also be used as feedstock to produce fuels and biochemicals. We herein review this pomegranate peel conversion technology and the prospective valorized product that can be synthesized from this frequently disposed fruit waste. The review also discusses its usage as a carbon substrate to synthesize bioactive compounds like phenolics, flavonoids and its use in enzyme biosynthesis. Based on reported experimental evidence, it is apparent that pomegranate peel has a large number of applications, and therefore, the development of an integrated biorefinery concept to use pomegranate peel will aid in effectively utilizing its significant advantages. The biorefinery method displays a promising approach for efficiently using pomegranate peel; nevertheless, further studies should be needed in this area. 2022 Elsevier Ltd -
Filamentous fungi for pharmaceutical compounds degradation in the environment: A sustainable approach
Pharmaceutical compounds play an important role in enhancing the quality of human life. They substantially increase the life expectancy of humans and the well-being of livestock. The expansion in the global human population has increased the usage of pharmaceuticals in an enormous way. This has led to the emergence of pharmaceutical compounds as environmental pollutants because these components are continuously released to various water sources and terrestrial ecosystems. The pharmaceutical components are released during their synthesis, as waste from human and veterinary healthcare sectors, and dumping of drugs that are not used. Pharmaceutical components are known to persist in their potential even at lower concentrations and can create serious issues for ecosystems, especially aquatic systems. Various efforts are being made to remove or reduce the toxicity of pharmaceutical components in aquatic systems. Bioremediation using fungi is one of the most secure and sustainable ways of decontaminating polluted environments. With their strong morphology and diverse metabolic abilities, Fungi employ different methods including fungal enzymes to clear pollutants. Studies have proven that fungi and fungal enzymes can transform these pharmaceutical compounds into less toxic components. This review highlights the role of fungi in the bioremediation of pharmaceutical compounds. 2023 The Author(s) -
Microbial Synthesis of Alkaloids and Applications in Healthcare
Plant alkaloids are a large group of natural compounds with wide-ranging bioactive characteristics, but the number of alkaloids obtained from the plant is low. Mass extraction of these bioactive alkaloids is affected by the trouble in large-scale propagation of these plants and absence of efficient strategies for extraction. However, production by chemical reactions is a substitute method; it is less effective due to its highly complex structure. The extensive study of alkaloid biosynthesis in plants and the advancement of genetic and metabolic engineering techniques enabled the opportunity to synthesise alkaloids through microbial hosts via metabolic engineering and bioprocess optimisations. In this chapter, we discuss the various gene-manipulation strategies to produce alkaloids in various microbial hosts and their application in the healthcare industry. 2023 selection and editorial matter, Ranjna Sirohi, Amit Kumar Rai, Luciana Porto de Souza Vandenberghe, and Binod Parameswaran; individual chapters, the contributors -
Microbial Enzymes for Synthesis of Chiral Drug Intermediates
Microbes or microbial enzymes can catalyze the synthesis of bioorganic compounds, and this process is defined as biocatalysis. Biocatalysis has become an essential technique in organic biotransformation, typically applied in chemical industries. Biocatalysts generally show high activity and excellent enantio, stereo, regio, and chemo-selectivity. They offer practical and cost-effective ways to synthesize semi-synthetic analogues and novel drug molecules. Many bacteria and fungi-derived enzymes could catalyze highly specific hydroxylations of various substrates that are highly complex to synthesize by chemical methods. This chapter details and discusses different biocatalytic microbial platforms that permit to produce the chiral drug intermediates. 2023 selection and editorial matter, Ranjna Sirohi, Amit Kumar Rai, Luciana Porto de Souza Vandenberghe, and Binod Parameswaran; individual chapters, the contributors -
Optimal Shortest Path Routing over Wireless Sensor Networks Using Constrained Genetic Firefly Optimization Algorithm
In Wireless Sensor Networks (WSNs), a large number of sensor nodes are placed over a specific area in any real-life application. The sensor node is small, with limited battery life, memory, and computing capacity. Due to the limited power of the battery, WSNs must expand the system life by minimizing the energy usage. In the existing system, the methods have limitations related to optimal shortest routing path, node energy consumption, network reconfiguration, and so on. In order to overcome these issues, aConstrained Genetic FireFly Optimization Algorithm (CGFFOA) is proposed. The CGFFOA algorithm is designed to select the best shortest path routing through the selection of Cluster Head (CH) nodes based on the better energy utilization, delay, and high throughput sensor nodes. It is used to optimize the routing path based on the energy, hop count, inter and intra cluster delay, and lifetime. The simulation findings therefore conclude that, with regard to reduced energy consumption, higher throughput, and lower end-to-end delay, the proposed CGFFOA algorithm is preferable to existing methods such as Particle Swarm Optimization (PSO) and Dynamic Source Routing (DSR). 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. -
SWITCHING INTENTION AND SWITCHING BEHAVIOR OF ADULTS IN THE NON-LIFE INSURANCE SECTOR: MEDIATING ROLE OF BRAND LOVE
In this digital era, customers in the insurance sector always look for better insurance products and services at an affordable price. When customers are unsure about service, they switch over to a better service provider. This behavior is more relevant to non-life insurance. However, the switching behavior of customers is hampered by certain switchover barriers such as brand consciousness, brand pride, brand loyalty, etc. This study focuses on exploring switching intentions and switching behaviors of adults in India keeping brand love as a mediator. A structured questionnaire was employed to collect the primary data from adults having non-life insurance products to analyze switching intentions and switching behaviors. The collected data were analyzed employing SPSS software and Hayes Process Model and appropriate statistical tools. The study results show that the switching intentions of adults vary based on their age, annual income, and education. Mean scores reveal that the lesser the age, the higher the intention to switch over. Further, based on annual income, adults who earn up to Rs 2 lakhs annually have more switching-over intentions (Mean score: 3.9719) followed by adults who earn Rs more than 2 lakhs to 5 lakhs annually (Mean score: 3.7590). Mean scores of education levels regarding switching intentions are higher among more educated adults and less among those who are qualified up to the school level. Arun Kumar N., Girish S., Suresha B., Mahesh E., 2023. -
Gender of the Firm Owner and Export Determinants of the Firms in India: an Empirical Analysis
This study aims to analyse the factors that influence the export decision of firms in India. These factors are unorthodox to the macroeconomic variables, for example, specific firm characteristics and resource stock variables that an enterprise in India may or may not have command over. The most significant of the firm characteristic variables is the gender of the firm owner. Given the binary identity of the explained variable (Export Status of a Firm), the paper uses Binary Logistic Regression. It reports the odds ratio for the individual variable interpretation. The study has also examined descriptive findings and model fit using the Hosmer. The study ceases a statistically significant relationship between the gender of the firm owner and the export decision of a firm. The odds of the firm being an exporter increases when the firm owner is a female. Further, the study also interprets several firm characteristics and resource stock variables that had an impact on the export decision of a firm in India. 2024 AESSRA. All rights reserved. -
Clustering of low-mass stars around Herbig Be star IL Cep - Evidence of 'Rocket Effect' using Gaia EDR3 ?
We study the formation and the kinematic evolution of the early-type Herbig Be star IL Cep and its environment. The young star is a member of the Cep OB3 association, at a distance of 798 9 pc, and has a 'cavity' associated with it. We found that the B0V star HD 216658, which is astrometrically associated with IL Cep, is at the centre of the cavity. From the evaluation of various pressure components created by HD 216658, it is established that the star is capable of creating the cavity. We identified 79 co-moving stars of IL Cep at 2-pc radius from the analysis of Gaia EDR3 astrometry. The transverse velocity analysis of the co-moving stars shows that they belong to two different populations associated with IL Cep and HD 216658, respectively. Further analysis confirms that all the stars in the IL Cep population are mostly coeval (?0.1 Myr). Infrared photometry revealed that there are 26 Class II objects among the co-moving stars. The stars without circumstellar disc (Class III) are 65 per cent of all the co-moving stars. There are nine intense H ? emission candidates identified among the co-moving stars using IPHAS H ? narrow-band photometry. The dendrogram analysis on the Hydrogen column density map identified 11 molecular clump structures on the expanding cavity around IL Cep, making it an active star-forming region. The formation of the IL Cep stellar group due to the 'rocket effect' by HD 216658 is discussed. 2021 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society. -
Fullerenes in the circumstellar medium of Herbig Ae/Be stars: insights from the Spitzer mid-infrared spectral catalog
This study presents the largest mid-infrared spectral catalogue of Herbig Ae/Be stars to date, containing the Spitzer Infrared Spectrograph spectra of 126 stars. Based on the catalogue analysis, two prominent infrared vibrational modes of C60 bands at 17.4 and 18.9 ?m are detected in the spectra of nine sources, while 7.0 ?m feature is identified in the spectra of HD 319896. The spectral index analysis and the comparison of the known sources with C60 features indicated that there exist two different types of emission classes among the sample of stars. The infrared spectra of six Herbig Ae/Be stars in this study resemble that of reflection nebulae, and their association with previously known reflection nebulae is confirmed. In the case of three Herbig Ae/Be stars, we report the tentative evidence of C60 emission features originating from the circumstellar disc or nearby diffused emission region. The detection fraction of C60 in the total HAeBe star sample is ?7 per cent, whereas the detection fraction is 30 per cent for HAeBe stars associated with nebulosity. In the catalog, C60 is exclusively present in the circumstellar regions of B type Herbig Ae/Be stars, with no evidence of its presence detected in stars with later spectral types. The present study has increased the number of young stellar objects and reflection nebulae detected with C60 multifold, which can help in understanding the excitation and formation pathway of the species. 2023 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society. -
On the Mass Accretion Rate and Infrared Excess in Herbig Ae/Be Stars
The present study makes use of the unprecedented capability of the Gaia mission to obtain the stellar parameters such as distance, age, and mass of HAeBe stars. The accuracy of Gaia DR2 astrometry is demonstrated from the comparison of the Gaia DR2 distances of 131 HAeBe stars with the previously estimated values from the literature. This is one of the initial studies to estimate the age and mass of a confirmed sample of HAeBe stars using both the photometry and distance from the Gaia mission. Mass accretion rates are calculated from H? line flux measurements of 106 HAeBe stars. Since we used distances and the stellar masses derived from the Gaia DR2 data in the calculation of the mass accretion rate, our estimates are more accurate than previous studies. The mass accretion rate is found to decay exponentially with age, from which we estimated a disk dissipation timescale of 1.9 0.1 Myr. The mass accretion rate and stellar mass exhibit a power-law relation of the form . From the distinct distribution in the values of the infrared spectral index, n2-4.6, we suggest the possibility of difference in the disk structure between Herbig Be and Herbig Ae stars. 2019. The American Astronomical Society. All rights reserved.. -
Discovery of an M-type companion to the Herbig Ae Star V1787 Ori
The intermediate-mass Herbig Ae star V1787 Ori is a member of the L1641 star-forming region in the Orion A molecular cloud. We report the detection of an M-type companion to V1787 Ori at a projected separation of 6.66 arcsec (corresponding to 2577 au), from the analysis of VLT/NACO adaptive optics Ks-band image. Using astrometric data from Gaia DR2, we show that V1787 Ori A and B share similar distance (d ?387 pc) and proper motion, indicating that they are physically associated. We estimate the spectral type of V1787 Ori B to be M5 2 from colour-spectral type calibration tables and template matching using SpeX spectral library. By fitting PARSEC models in the Pan-STARRS colour-magnitude diagram, we find that V1787 Ori B has an age of 8.1$^{+1.7}_{-1.5}$ Myr and a mass of 0.39$^{+0.02}_{-0.05}$ M. We show that V1787 Ori is a pre-main-sequence wide binary system with a mass ratio of 0.23. Such a low-mass ratio system is rarely identified in Herbig Ae/Be binary systems. We conclude this work with a discussion on possible mechanisms for the formation of V1787 Ori wide binary system. 2020 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society. -
Studies on dark matter dark energy and possible alternate models
The nature of dark matter (DM) and dark energy (DE) which is supposed to constitute about 95% of the energy density of the universe is still a mystery. There is no shortage of ideas regarding the nature of both. While some candidates for DM are clearly ruled out, there is still a plethora of viable particles that fit the bill. In the context of DE, while current observations favour a cosmological constant picture, there are other competing models which may be equally likely. The standard model for the formation of structure assumes that there newlineexisted small fluctuations in the early universe that grew due to gravitational instability. The origin of these fluctuations are still unclear. In this study, we proposed the role of dark matter in providing the seed for star formation in the early universe, which is supported by very recent observations. With this we set observable constraints on luminosities, temperatures, and lifetimes of the early stars with an admixture of dark matter. We also studied the effects of the background repulsive dark energy density for large scale cosmic structures. The relation, and#119872;and#8260;and#119877;2 and#8776; 1and#119892;/and#119888;and#119898;2, seems to hold true for primeval galaxies as well as those at present epoch. From this, we set constraints on the nature and evolution of dark energy. Besides, we also set constraints on the size of galaxy clusters and superclusters due to the repulsive cosmological dark energy. This could indicate as to why large scale cosmic structures much larger than and#8764;200 Mpc are not seen.This study also looked at the evolution of the concept of the cosmological constant from its inception a little over a hundred years ago when Einstein introduced the cosmological constant in his General Theory of Relativity newlinein order to obtain a static universe to conform to the philosophical view of newlinethe universe at that time to it possibly making up close to about 70% of the energy density of the universe. -
Energy and Environmental Applications of Polymer Based Mixed Metal Oxide Nanocomposites
The dependence of human lives on fossil fuels is very inevitably high for the development of society. This leads to the exploitation of these non-renewable sources, which brings forth society, which is another major issue that has to be tackled. In this study, we have focused on addressing the energy and environmental needs of society using different catalysts. The polymer based mixed metal oxide catalysts are used for the utility towards multiple applications. The energy issues can be mitigated through newlinesupercapacitance studies and water splitting studies. The water splitting studies can newlineproduce hydrogen, an efficient and eco-friendly fuel, and supercapacitors can store newlineenergy effectively. Water pollution is another problem faced by our society, which newlinereduces the availability of freshwater sources. This can be overcome by following newlineeffective and cost-efficient adsorption techniques. Another major threat that prevails in our society is corrosion. Corrosion inhibition studies are followed to tackle this issue and provide a corrosion-free environment. The various polymers used in this study are polyaniline, polypyrrole, poly (3,4-ethylenedioxythiophene), and chitosan. These polymers are mixed with different metal oxides, and the synergy between the polymers and metal oxides provides efficiency towards the mentioned applications. The successful formation of composites is confirmed using various characterization techniques. Several electrochemical studies like cyclic voltammetry, galvanostatic charge-discharge studies, electrochemical impedance spectroscopy, linear sweep voltammetry, and potentiodynamic techniques are employed to analyze the efficacy of the composites towards supercapacitance, water splitting, and corrosion inhibition studies. The batch adsorption studies are executed for water purification studies. The synthesized multifunctional composites can be used as potential candidates for addressing the energy and environmental needs of our society in a sustainable manner.