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Extraction of Fungal Chitosan by Leveraging Pineapple Peel Substrate for Sustainable Biopolymer Production
The cost-effective production of commercially important biopolymers, such as chitosan, has gained momentum in recent decades owing to its versatile material properties. The seasonal variability in the availability of crustacean waste and fish waste, routinely used for chitosan extraction, has triggered a focus on fungal chitosan as a sustainable alternative. This study demonstrates a cost-effective strategy for cultivating an endophytic fungus isolated from Pichavaram mangrove soil in a pineapple peel-based medium for harvesting fungal biomass. Chitosan was extracted using alkali and acid treatment methods from various combinations of media. The highest chitosan yield (139 0.25 mg/L) was obtained from the pineapple peel waste-derived medium supplemented with peptone. The extracted polymer was characterized by FTIR, XRD, DSC, and TGA analysis. The antioxidant activity of the fungal chitosan was evaluated using DPPH assay and showed an IC50 value of 0.22 mg/L. Subsequently, a transparent chitosan film was fabricated using the extracted fungal chitosan, and its biodegradability was assessed using a soil burial test for 50 days. Biodegradation tests revealed that, after 50 days, a degradation rate of 28.92 0.75% (w/w) was recorded. Thus, this study emphasizes a cost-effective strategy for the production of biopolymers with significant antioxidant activity, which may have promising applications in food packaging if additional investigations are carried out in the future. 2024 by the authors. -
Exploring the Psychosocial Challenges and Strengths of Indigent Adolescents: A Reflexive Thematic Analysis of Counsellors Insights
Background: The Bronfenbrenner bioecological model of human development provides a comprehensive framework for understanding the complex interactions between individual factors and environmental influences on adolescent mental health, such as limited access to resources, exposure to violence and trauma, and parental neglect. While discussing the challenges faced by at-risk adolescents, it is important to focus on the strengths of resilient adolescents living in similar conditions. These individual differences are the precursors in determining their futures. Methods: The present study aimed to explore the psychosocial challenges and strengths of indigent adolescents. Eight counselors who had been working with indigent adolescents for at least three years in school or NGO settings were identified through a snowball sampling design and interviewed using a semi-structured interview schedule. Results: Reflexive thematic analysis of the interviews was done using Braun and Clarks protocol to identify themes. Challenges faced by indigent adolescents were a lack of parental supervision, vulnerability to cybercrime, emotional dysregulation, engagement in drug use, ambiguity in life aspirations and career goals, and societal mistrust and bias. The strengths identified were empathy, reconciliation dynamics and forgiveness, a yearning for change, a love of learning, help-seeking and help-providing behavior, attachment to religion and festivals, and a sense of gratitude and hopefulness, which indigent resilient adolescents display to navigate through their challenging lives. A detailed discussion of these challenges and strengths, along with their various dynamics, has also been provided. Conclusion: Identifying both the difficulties and strengths of indigent adolescents would promote more strength-based approaches to preventive and promotive mental health programs. 2024 The Author(s). -
Economic globalization and unemployment: Evidence from high-, middle- and low-income countries
This study intends to empirically evaluate the effects of economic globalization and its components (i.e. trade and financial openness) on unemployment in high-, middle- and low-income countries from 1991 to 2020. Further, it considers real GDP per capita (sectoral divisions of income, i.e. agriculture, industry and service sector) and urbanization as control variables in the unemployment function. On the empirical front, this study employs the Panel Dynamic Simulated ARDL model and the Kernel-Based Regularized Least Squares for long-run influence estimations. The emanating outcome of these analyses states that economic globalization destroys employment opportunities for low-income countries as it enhances unemployment in the long run. However, in high- and middle-income countries, economic globalization creates employment, which implies reducing unemployment in the long run. The result also indicates that trade and financial openness destroy employment opportunities in low-income countries. Although trade openness in middle-income countries shows the same effect, financial openness does not mimic the same. For high-income countries, trade openness reduces unemployment, but financial openness fosters it. Therefore, these findings indicate that to keep unemployment at a low level, policies related to the opening up of the economy in terms of factor mobility, offshoring, outsourcing and international trade need to be implemented in low-income countries. Moreover, a similar consideration is needed for high and middle-income countries to avoid faraway repercussions on unemployment due to becoming a peripheral country. 2024 John Wiley & Sons Ltd. -
Spectroscopic investigation on shuttlecock-shaped liquid crystalline trimers: Mesomorphic behaviour and its application in optical storage devices
In this paper, we discuss the synthesis and characterization of 2,3,4-tris[n-((4-(-cyanophenyl)diazenyl)phenoxy)alkyloxy]benzonitrile obtained by coupling 2,3,4-trihydroxy benzonitrile and (E)-4-((4-((n-bromoalkyl)oxy)phenyl)diazenyl)benzonitrile, pertain to shuttlecock shaped liquid crystals. The molecular structure was confirmed by NMR spectroscopic and elemental analyzer. The thermal behavior of the trimers was assessed using a polarizing optical microscope (POM) and differential scanning calorimetry (DSC). The three diazo groups in the trimers enabled us to study the photo-isomerization effect and evaluate their potential applications in optical storage devices. Importantly, we found these trimers easy to synthesize and process, paving the way for cost-effective alternatives to traditional LC materials. We fabricated an optical storage device to study the light effects on shuttlecock-shaped LC trimers, demonstrating that the geometry of the trimers plays a crucial role in determining structure-property relationships. 2024 -
Psychoneuroimmunological Perspective of Animal - Assisted Therapy
Animal-assisted therapy is a new and upcoming form of therapy that has shown multifarious benefits to participants. It is a goal-oriented therapeutic process with the incorporation of a qualified therapy animal in the therapeutic activities and conversations. This paper explores these benefits from a psychoneuroimmunological lens, wherein the interplay of and impact on an individual's psychological, neurological and immune systems are discussed. Positive physical interaction with therapy animals reduces undesirable symptoms and ailments such as stress, anxiety, depressive symptoms, aggressive tendencies, harmful behaviours, cardiovascular issues and unhealthy tendencies amongst others. It further promotes a healthier lifestyle, promoting quality of life, better heart health, cognitive functioning and overall well-being. The biological basis of these benefits is discussed. 2024 Oriental Scientific Publishing Company. All rights reserved. -
Humour as a Moderator Between Hassles and Well-Being
Humour is a universal phenomenon that offers several physiological and psychological benefits across cultures. The objectives of this study were to examine the relationships between daily hassles, humour and well-being; and to investigate the moderating effect of humour on the relationship between hassles and well-being. A correlational design was adopted to collect data from 644 participants (men = 300, women = 344), aged between 18 and 58years using purposive and snowballing sampling techniques. The Daily Hassles Scale, Sense of Humour Questionnaire (SHQ-R) and the Personal Well-Being IndexAdult (PWI-A) were administered to the sample. The self-report measures were appropriately scored and the collective data were analyzed. Statistical analyses revealed a positive relationship between sense of humour and well-being. A negative relationship was observed between sense of humour and hassles; and between well-being and hassles. Further, sense of humour was found to be moderating the relationship between daily hassles and well-being. This study highlights the role of humour in softening the impact of hassles on the well-being of the Indian population. This strengthens the construct of humour in the context of positive psychology. The Author(s) under exclusive licence to National Academy of Psychology (NAOP) India 2024. -
Synergistic advancements in energy storage: g-C3N4/NiFe2O4/PANI composite with augmented electrochemical capabilities
This study examines the electrochemical behaviour of a hybrid composite material of graphitic carbon nitride/Nickel ferrite/Polyaniline (g-C3N4/NiFe2O4/PANI) synthesized by hydrothermal method, coupled with in-situ polymerisation. The ensuing g-C3N4/NiFe2O4/PANI composite demonstrates superior characteristics for energy storage applications. Through a comprehensive analysis, we elucidate the combined effects of the distinct components, revealing improved electrochemical properties. The composite exhibits improved galvanostatic charge/discharge exhibiting a specific capacitance of 770 Fg?1 at 1 Ag?1 current density. This research underscores the perspective of the g-C3N4/NiFe2O4/PANI composite as a promising candidate for advanced energy storage systems. 2024 Elsevier Ltd -
Renewable Musa Sapientum derived porous nano spheres for efficient energy storage devices
Biomass-based carbonaceous materials derived from Musa Sapientum have gained much attention in recent years for their application in energy storage devices, especially supercapacitors. In the present work, we synthesized carbonaceous material from banana peel as the biomass precursor by using a pyrolysis method carried out at various temperatures (600, 800, and 1000 C). The characterization of the prepared carbonaceous materials BP600, BP800 and BP1000 was done by using different characterization techniques such as FTIR, XRD, FE-SEM, and TEM, studies. The electrochemical study of the synthesized material was carried out by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) electrochemical impedance spectroscopy (EIS). The supercapacitive performance of the material was studied using a 3-electrode system with 3M KOH as an electrolyte. As a result, the BP600 exhibited a better specific capacitance with higher energy and power densities along with a maximum cyclic stability of 16,000 cycles. To show the practical applicability of the material BP 600, two electrode system studies were carried out as well, which showed preferentially good values for specific capacitance with appreciable power and energy density values. The study provides us with a green approach for the fabrication of non-toxic, low-cost, and environmentally friendly potential porous carbonaceous electrode materials by converting bio-waste into a clean and renewable source of energy. 2024 The Author(s). Published by IOP Publishing Ltd. -
Technology acceptance model and customer engagement: mediating role of customer satisfaction
The primary aim of this study is to examine the influence of the technological acceptance model on customer engagement. An additional aim of this study is to examine the mediating effect of customer satisfaction in the relationship between the technology acceptance model and customer engagement. The present study gathered primary data from users of retail banking services in specific metropolitan areas in India. The participants were chosen based on their considerable expertise in utilizing online, digital, and mobile banking platforms and their substantial knowledge of implementing advanced e-banking strategies. The application of confirmatory factor analysis investigated measurement validity. The studys findings indicate a significant correlation between emotional and rationalengagement, mediated via perceived usefulness. Additionally, the study revealed that the relationship between perceived usefulness and emotional engagementis mediated by customer satisfaction. Furthermore, it can be observed that this factor entirely mediates the relationship between transaction cost and emotional engagement. The studys findings suggest that customer satisfaction is a complete mediator in the association between transaction cost and rational engagement. The results of this study make a valuable contribution to the current body of literature on the technological acceptance model, customer satisfaction, and customer engagement. The Author(s), under exclusive licence to Springer Nature Limited 2023. -
Enhancing stochastic optimization: investigating fixed points of chaotic maps for global optimization
Chaotic maps, despite their deterministic nature, can introduce controlled randomness into optimization algorithms. This chaotic map behaviour helps overcome the lack of mathematical validation in traditional stochastic methods. The chaotic optimization algorithm (COA) uses chaotic maps that help it achieve faster convergence and escape local optima. The effective use of these maps to find the global optimum would be possible only with a complete understanding of them, especially their fixed points. In chaotic maps, fixed points repeat indefinitely, disrupting the map's characteristic unpredictability. While using chaotic maps for global optimization, it is crucial to avoid starting the search at fixed points and implement corrective measures if they arise in between the sequence. This paper outlines strategies for addressing fixed points and provides a numerical evaluation (using Newton's method) of the fixed points for 20 widely used chaotic maps. By appropriately handling fixed points, researchers and practitioners across diverse fields can avoid costly failures, improve accuracy, and enhance the reliability of their systems. 2024 Institute of Advanced Engineering and Science. All rights reserved. -
The accumulation, antioxidant defences, and secondary metabolite production in common sage (Salvia officinalis L.) under lead toxicity
The growing levels of lead (Pb) in agricultural soil and water bodies as a result of industrialization and human activity present serious challenges for medicinal plants. The present study investigates the complex responses of Salvia officinalis to toxicity caused by Pb including metal accumulation, translocation dynamics, antioxidant defenses, and the production of secondary metabolites. Pb showed preferential accumulation in the roots, peaking at (1000 ppm Pb) (2484.2 mg kg-1). The reduced levels of total chlorophyll (1.29-fold), protein (1.9-fold), and carbohydrate (2.5-fold) under prolonged exposure to stress demonstrate the toxic impacts of lead. Proline and total phenolic content (TPC) increased concentration-dependently under lead stress, while flavonoids were found to be decreased with the enhancement of lead toxicity. Enzymatic antioxidants (catalase, APX, and SOD) showed notable increase, especially in the 30 days of treatment, demonstrating the plants strong defenses. S. officinaliss adaptive responses were highlighted by concentration-dependent increases in non-enzymatic antioxidants such as total antioxidant capacity (TAC) and DPPH radical scavenging activity. Crucially, under lead stress, S. officinalis showed 1.7-fold increased rosmarinic acid (RA) production, in plants exposed to 200 ppm for 30 days treatment. However, further exposure to lead significantly caused the reduction of RA production. The results add to our knowledge of how sage plants respond to environmental stress and offer important insights for future uses in phytoremediation and the breeding of stress-tolerant plant cultivars. Furthermore, the research highlights about the S. officinaliss potential as a source of bioactive compounds possessing antioxidant qualities, under low levels of lead stress. 2024, Indian journals. All rights reserved. -
Structural modification of electrophilic group substituted phenyldiazenyl derivatives for antitubercular application
In the present work, four electrophilic group substitute phenyldiazenyl derivatives were synthesized using an electrophilic substitution reaction. The physicochemical analysis was carried out using FT-IR, 1H NMR, and HR-MS data. The photophysical studies were carried out using theoretical methods. Density functional theory was employed to illustrate the electronic and optical characteristics of the synthesized compounds. The HOMO-LUMO energies were theoretically computed in different solvents using Gaussian 09W software and results are compared with the experimental values. The molecule PT4 shows highest bandgap of 4.497eV. Further, the global chemical reactivity descriptors were used to determined nature of chemical reactivity. The anti-tubercular activity was evaluated using invitro and molecular docking techniques and results reveal that barbituric acid coupled with phenyldiazenyl displayed excellent anti-tubercular activity compared with the standard Gentamycin. 2024 Indian Chemical Society -
Bed shear stress distribution across a meander path
Laboratory experimentation for bed shear stress distribution has been carried out in two sets of meandering channels. The channels have crossover angles of 110 and 60 constructed by sine-generated curves over a flume of 4 m width. Variations in bed roughness were studied for the meandering main channel. Bed shear stress distribution across a meandering length for the 110 and 60 channels was examined for different sinuosities and roughnesses. The boundary shear stress study illustrated the position of maximum shear along the apex section and across the meandering path. These variations were observed for different flow depths. A comparison of the bed shear among the three experimental channels was conducted, and the results were analyzed. 2024, IWA Publishing. All rights reserved. -
Structural investigation of Cr2CTx/NiFe2O4 MXene composite as a bifunctional electrocatalyst for water splitting
The electrocatalytic water splitting offers great potential as an environmentally friendly and sustainable method to produce hydrogen and oxygen, the former serving as a renewable alternative to traditional fossil fuels. MXene, a novel two-dimensional (2D) layered class of materials, has gained enormous attention as an electrocatalyst for water splitting. This versatile material can be tailored to enhance its electroactive surface sites and stability toward electrocatalytic performance. Herein, we have designed a 2D hybrid material, Cr2CTx/NiFe2O4, via an in-situ hydrothermal approach. NiFe2O4 spheres decorated on layered-Cr2CTx are subjected to analysis using XRD, FTIR, TGA, XPS, FESEM, HRTEM-SAED, and optical profilometry. The synthesized hybrid MXene material shows outstanding activity for overall water splitting compared to Cr2CTx and NiFe2O4. Cr2CTx/NiFe2O4 exhibits an overpotential of 144 mV and 159 mV at a current density of 10 mA cm?2 for hydrogen evolution and oxygen evolution reactions, respectively, and achieves a cell potential of 1.69 V for overall water splitting. This study reveals valuable insights on bi-functional 2D hybrid MXene materials for electrocatalytic water splitting. 2024 Elsevier B.V. -
Cloud databases: A resilient and robust framework to dissolve vendor lock-in
Vendor lock-in has become a major concern in cloud computing. The term vendor lock-in describes situations where the subscriber cannot move data or services to another cloud vendor. This is due to heavy data volumes, high network bandwidth costs, dependencies, or unacceptable downtime. The proposed vendor lock-in dissolution practice migrates the database effectively in noticeably less time, regardless of database size and with a nominal network bandwidth requirement. Through this new practice, databases can be migrated to very remote regions, even across continents. A real-time implementation of the proposed method presented in this paper. 2024 The Author(s) -
MATHEMATICAL MODEL OF NICKEL-GRAPHENE COMPOSITE INKS FOR JETTING PROPERTIES IN INKJET PRINTING
The droplet formation process in inkjet printing is studied numerically and verified through a simulation model. The droplet formation process decides the printing quality of the coating, and a mathematical model is developed to understand the complete process from droplet formation to detachment. The Navier-Stokes equation is used to mathematically derive the droplet radius (rnumerical). COMSOL multiphysics is used for simulation and the radius (rsimulation) is calculated from the droplet mass. The rnumerical and rsimulation are compared for inks containing nickel, graphene, and nickel-graphene composite ink it is observed that the composite ink radiuses have the lowest difference (rsimulation - rnumerical = 0.085 m). A droplet is formed at 1.47 mm from the nozzle inlet, for nickel-graphene ink, and after 1.5mm for other pristine inks. The results are verified through Z number, velocity profile, and droplet mass. The droplet formation observed from the velocity profile is earliest at 120 s. It is seen that a stable droplet is generated at 100s for nickel-graphene ink and at 200 s for individual inks. 2024 Faculty of Science, Universiti Malaya. All rights reserved. -
En route to Khardung La with Dhak Dhak
Dhak Dhak uses the trope of a motorcycle road trip to discuss several societal and emotional barriers women ought to overcome to forge their own paths and blossom into their authentic selves. 2024 Economic and Political Weekly. All rights reserved. -
Chernobyl Disaster Optimizer-Based Optimal Integration of Hybrid Photovoltaic Systems and Network Reconfiguration for Reliable and Quality Power Supply to Nuclear Research Reactors
In view of the complexity and importance of nuclear research reactor (NRR) installations, it is imperative to uphold high standards of reliability and quality in the electricity being supplied to them. In this paper, the performance of low-voltage (LV) distribution feeders integrated with NRRs is improved in terms of reduced distribution loss, improved voltage profile, and reduced greenhouse gas (GHG) emissions by determining the optimal location and size of photovoltaic (PV) systems. In the second stage, the power quality of the feeder is optimized by reducing the total harmonic distortion (THD) by optimally allocating D-STATCOM units. In the third and fourth stages, the reliability and resilience aspects of the feeder are optimized using optimal network reconfiguration (ONR) and by integrating an energy storage system (ESS). To solve the non-linear complex optimization problems at all these stages, an efficient meta-heuristic Chernobyl disaster optimizer (CDO) is proposed. Simulations are performed on a modified IEEE 33-bus feeder considering the non-linear characteristics of NRRs, variability of the feeder loading profile, and PV variability. The study reveals that the proposed methodology can significantly improve the service requirements of NRRs for attaining sustainable research activities. 2024 by the authors. -
Purification and evaluating in vitro activity of a fibrinolytic protease produced by a mangrove isolate Bacillus subtilis AIBL_AMSB2_M7E32
One of the main causes of heart-related problems globally is intravascular thrombosis. Microbial fibrinolytic proteases play a very crucial role in the management of thrombosis. Plasminogen activators and plasmin-like proteins, which are fibrinolytic enzymes of microbial origin, hydrolyze thrombin with great efficacy and without causing noticeable side effects. These fibrinolytic enzymes can also be manufactured efficiently and economically in huge quantities within a short period. However, the search for novel fibrinolytic enzymes demands difficult purification procedures, as well as physicochemical and structural-functional properties that provide information about their mode of action. In this study, the strain named Bacillus subtilis AIBL_AMSB2_M7E32, isolated from the Coringa mangrove soils, was shown to produce a fibrinolytic enzyme. The enzyme was purified by a four-step purification process that resulted in a 43.33-fold purification with a specific activity of 6368.20 (U/mg). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the purified enzyme was a protein of about 28 kDa and showed fibrinolytic activity on a zymogram. In vitro assay on blood clots revealed that the purified enzyme could lyse the blood effectively by a percentage of 72.96 0.16a%, indicating that the enzyme could be used as a fibrinolytic agent. Furthermore, an observation for enzyme stability and its in vivo activity studies would be necessary for its application in the market. 2024 Bhavana Sompalli and Alok Malaviya. -
Analyzing the therapeutic significance of Strelitzia reginae Banks: Exploring its physico-chemical properties, elemental makeup, and antimicrobial activity
Plants constituting biologically active molecules with curative value have overtime showed advantage as subject of researches. Strelitzia reginae (Bird of Paradise) is a member of the Strelitziaceae family. Several South African tribes used plant parts to treat the venereal diseases and inflamed glands. The study aimed to investigate therapeutic potential of leaf and root extracts of S. reginae by assessing the physico-chemical properties, elemental analysis. Elemental analysis was carried out by Atomic Absorption Spectrometry (AAS) method, quantitative phytochemical analysis was carried out using, Gas Chromatography and Mass Spectrometry (GC-MS) analysis. The leaf and root of S. reginae were extracted using soxhlet technique of extraction and was further concentrated with a rotary evaporator. Standard protocols assessed the plants elemental compounds, physico-chemical properties, qualitative and quantitative phytochemicals, GC-MS analysis, antioxidant activity using DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assay, phosphomolybdate assay, ferric reducing power assay (FRAP), metal chelating assay, and antimicrobial potential by well diffusion test. The results of AAS exhibited that the leaf and root contain more calcium and less of cadmium content. Preliminary phytoconstituents showed the presence of medicinally important alkaloids, anthraquinones, tannins, carbohydrates, flavonoids, saponins, phenols, proteins, and amino acids. The quantitative phytochemical analysis revealed that the leaf has higher total phenolic, flavonoid, chlorophyll, carbohydrates, protein, and proline contents than root. GC-MS analysis verifies the existence of bioactive components like squalene, hexatriacontane, phytol, hexacosane, heptacosane, and octacosane. DPPH, phosphomolybdate assay, FRAP and metal chelating antioxidant analysis revealed excellent activity in leaf and in root sample. As various South African tribes employed plant parts to treat sexual diseases and swollen glands, the antimicrobial property was investigated for the first time using a well-diffusion approach, and both plant parts revealed significant antibacterial and antifungal efficacy against recognized strains. The current study showed S. reginaes therapeutic potential and asked for more pharmacological and biological research to boost the importance of the worlds unevaluated herbal plants. 2024, Indian journals. All rights reserved.