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Highly emissive dibenzofuranfluorophores with aggregation-induced emission for bioimaging in HeLa cell lines
Dibenzo[b,d]furans, structural analogs of furan, represent an emerging class of promising molecules whose solid-state emission properties remain largely unexplored. The aim of the present work is to design and synthesize new dibenzo[b,d]furan-based organic fluorophores for bioimaging applications. The synthesis involved a single-step Schiff base reaction of 4-(dibenzo[b,d]furan-4-yl)aniline with two different ortho-hydroxy aldehydes, furnishing DBF1 and DBF2 in high yields. Both fluorophores DBF1 and DBF2 exhibited high fluorescence in their solid and aggregated states. The photophysical properties in solution, solid, and aggregated states were investigated using absorbance and emission spectroscopy. The aggregation process was confirmed by the particle size analysis using dynamic light scattering (DLS). The cytotoxicity of the molecules was investigated against HeLa cell lines by the standard MTT assay. DBF1 and DBF2 demonstrated exceptional photoluminescence with quantum yields reaching up to 17.89% and 2.26% respectively, highlighting their potential as excellent materials for imaging applications. Both DBF1 and DBF2 exhibited significant toxicity towards HeLa cells with IC50 values of 42.08 ?g ml?1 and 39.74 ?g ml?1, respectively, showcasing notable anti-proliferative activity against HeLa cells. Both fluorophores exhibited excellent emission in HeLa cells with mean relative fluorescence intensities of 1.008 0.77 a.u. and 1.44 0.65 a.u. for DBF1 and DBF2, respectively. Thus, this work presents the lesser explored dibenzo[b,d]furan-based organic fluorophores for bioimaging applications with potential inhibitory activity against HeLa cells. 2025 The Royal Society of Chemistry. -
Highly Luminescent MOF and Its in Situ Fabricated Sustainable Corn Starch Gel Composite as a Fluoro-Switchable Reversible Sensor Triggered by Antibiotics and Oxo-Anions
Frequent use of antibiotics and the growth of industry lead to the pollution of several natural resources which is one of the major consequences for fatality to human health. Exploration of smart sensing materials is highly anticipated for ultrasensitive detection of those hazardous organics. The robust porous hydrogen bonded network encompassing a free-NH2 moiety, Zn(II)-based metal-organic framework (MOF) (1), is used for the selective detection of antibiotics and toxic oxo-anions at the ppb level. The framework is able to detect the electronically dissimilar antibiotic sulfadiazine and nitrofurazone via fluorescence "turn-on"and "turn-off"processes, respectively. The antibiotic-triggered reversible fluoro-switching phenomena (fluorescence "on-off-on") are also observed by using the fluorimetric method. An extensive theoretical investigation was performed to establish the fluoro-switching response of 1, triggered by a class of antibiotics and also the sensing of oxo-anions. This investigation reveals that the interchange of the HOMO-LUMO energy levels of fluorophore and analytes is responsible for such a fluoro-switchable sensing activity. Sensor 1 showed the versatile detection ability which is reflected by the detection of a carcinogenic nitro-group-containing drug "roxarsone". In view of the sustainable environment along with quick-responsive merit of 1, an in situ MOF gel composite (1@CS; CS = corn starch) is prepared using 1 and CS due to its useful potential features such as biocompatibility, toxicologically innocuous, good flexibility, and low commercial price. The MOF composite exhibited visual detection of the above analytes as well as antibiotic-triggered reversible fluoro-switchable colorimetric "on-off-on"response. Therefore, 1@CS represents a promising smart sensing material for monitoring of the antibiotics and oxo-anions, particularly appropriate for the real-field analysis of carcinogenic drug molecule "roxarsone"in food specimens. 2022 American Chemical Society. -
Highly luminescent ZnS:Mn quantum dots capped with aloe vera extract
This study demonstrates the optical properties of ZnS:Mn2+ qquantum dots synthesized by simple and eco-friendly chemical precipitation method using aloe vera (AV) extract as the stabilizing agent. The nanoparticles have been characterized by transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, diffuse reflectance spectroscopy (DRS), photoluminescence (PL) and time-resolved PL spectroscopy. Increase in band gap energy with decrease in particle size was observed from DRS studies due to quantum confinement effect. Dominant yellow emission was observed from characteristic 4T1?6A1 transitions of the Mn2+ions in the ZnS:Mn/AV nanoparticles. The results provide insight to the quantum confinement effect that occur and how it affect decay life time of the ZnS:Mn2+/AV nanoparticles. 2020 Elsevier Ltd -
Highly mixed high-energy d-orbital states enhance oxygen evolution reactions in spinel catalysts
Design, synthesis, and engineering of electrocatalysts for the oxygen evolution reaction (OER) are essential for attaining desirable electrocatalytic performance towards practical implementation. Emerging spinel-type OER catalysts have not reached the desirable activity and durability, thus demanding critical research to advance the field. To achieve enhanced OER performance for spinel-type OER catalysts, we present an efficient strategy of electronic structure modulation of central metal atoms. Modulation of the electronic properties of the Zn and Co atoms through the counter anionic components (O, S, and Se) regulates the adsorption of oxygen intermediates and thus enhances OER activity, which is systematically demonstrated using Density Functional Theory (DFT) calculation. Although the zinc cobalt selenide catalyst showed the less pronounced trigonal distortion, the mixing of eg orbitals with selenium accounts for the experimentally observed enhancement in OER activity. The result is, in contrast to the benchmark catalyst made of RuO2, ZnCo2Se4@rGO demonstrated lower OER overpotential (?10 = 302 mV) and Tafel slope (58 mV dec?1) as well as greater durability at 10 mA cm?2 for 50 h. The implementation of this strategy in several spinel-type catalysts could improve their electrocatalytic performance. 2023 Elsevier B.V. -
Highly secured authentication and fast handover scheme for mobility management in 5G vehicular networks
The Fifth Generation (5 G) networks exhibit high flexibility and diversity in their design and deployment strategies. Transitions between base stations (BSs), heterogeneous networks (HetNets) and other cellular networks provide significant vulnerabilities and expose users to substantial risks associated with cybersecurity attacks. This article evaluates current handover authentication methods in the context of 5 G networks while proposing a set of security criteria for handover authentication. This study presents a novel authentication technique called SHK (Secure Handover Key) that utilizes SDNs (Software Defined networks). The proposed scheme integrates recycled lightweight dynamic key cryptography and combines security features such as perfect forward secrecy and robustness to leakages. The significance of the proposed approach is assessed in terms of computations, communications, signals, and energy costs on 5 G mobility applications and Vehicular Communication Networks (VCNs). The scheme employed in this study demonstrates enhanced security measures and improved changeover performance compared to conventional schemes. 2024 Elsevier Ltd -
Highly selective derivative spectrophotometric determination of palladium(II) in hydrogenation catalysts and alloy samples
A simple, selective and sensitive derivative spectrophotometric method has been developed for the determination of palladium(II) using a newly synthesised reagent diacetylmonoxime-(p-anisyl)-thiosemicarbazone in acetic acid medium. The molar absorptivity and Sandell's sensitivity of the coloured species are 3.8 104 L mol-1 cm-1 and 2.8 ng cm-2, respectively. Beer's law is obeyed between 0.2-2.0 ?g mL-1 of Pd(II) at 440 nm. The stoichiometry of the complex is found to be 1:2 (metal:ligand). Calibration graph for the first order derivative spectrophotometric determination of palladium(II) is derived by measuring derivative amplitudes at 480 nm with a linear range 0.15-2.6 ?g mL-1. The metal ions, which are normally associated with palladium in mineral and alloy samples, do not interfere. The proposed method has been successfully applied for the trace level determination of palladium in hydrogenation catalysts and some synthetic mixtures. -
Highly selective first order derivative spectrophotometric determination of osmium(VIII) using anthranilic acid as a chromogenic reagent
A simple, selective and sensitive spectrophotometric method has been developed for the determination of osmium(VIII) using anthranilic acid as a reagent in the presence of Triton X-100. The molar absorptivity and Sandells sensitivity of the violet coloured species are 3.03 104L mol-1cm-1 and 3.5 ng cm-2 respectively. Beers law is obeyed between 0.5-5.5 ?g mL-1 of Os(VIII) at 500 nm. The stoichiometry of the complex is found to be 1:2 (metal: ligand). Calibration graph for the first order derivative spectrophotometric determination of Os(VIII) is derived by measuring derivative amplitudes at 525 nm with a linear range 0.25-5.5 ?g mL-1. The detection limit and quantitation limit of first order derivative spectrophotometry are found to be 0.075 and 0.25 ?g mL-1, respectively.1 1The metal ions, which are normally associated with osmium in catalysts and alloy samples, do not interfere. The proposed method has been successfully applied for the trace level determination of osmium in various synthetic mixtures containing commonly associated metal ions and corresponding to the alloy composition. 2015, National Institute of Science Communication and Information Resources (NISCAIR). All rights reserved. -
Highly selective first order derivative spectrophotometric determination of osmium(VIII) using anthranilic acid as a chromogenic reagent /
Indian Journal Of Chemical Technology, Vol.22, Issue 5, pp.234-240, ISSN No: 0975-0991 (Online), 0971-457X (Print). -
Highly strengthened mechanical, morphological, IR vibrational and optical properties of rationally tailored wheat starchchitosan blends crosslinked with dual UV/acetic acid system for sustainable green packaging
Through this study, wheat starch/chitosan composite (SCB) films were successfully developed via a UV/acetic acid-assisted solution?casting approach with varying chitosan ratios. Tensile testing shows that stress at break remains nearly unchanged at lower chitosan content (1030?wt%) but increases abruptly beyond 30?wt%, reaching an optimum value at 50?wt% due to intensified hydrogen bonding and cross-linking between chitosan NH?? and starch OH? groups. Strain at break follows a similar trend, with markedly elevated elongation and elasticity. Youngs modulus exhibits the highest rigidity at 50?wt%, while stiffness decreases thereafter, consistent with enhanced elastic deformation. Morphological analysis reveals that chitosan incorporation transforms starch films from brittle, cracked surfaces to densely compact structures with fewer pore defects, resulting in superior adhesion and integrity. UVvis results show improved UV shielding, higher transparency, and tunable absorption, while FTIR analysis confirms only physical interactions with no new bonds formed between the components. Overall, chitosan incorporation significantly fortifies the SCB films by improving mechanical strength, structural stability, and optical performance, extending their application as green, multifunctional materials for sustainable packaging, coatings, and wastewater treatment. 2026 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license. http://creativecommons.org/licenses/by-nc-nd/4.0/ -
Highly Surface Active Anisotropic Silver Nanoparticles as Antimicrobial Agent Against Human Pathogens, Mycobacterium smegmatis and Candida albicans
Rapid synthesis of anisotropic silver nanoparticles via cost-effective, non-hazardous, and eco-friendly methods using naturally available gums are of greater significance as their chemical synthesis is associated with high toxicity. This study aims to synthesize highly surface-active anisotropic silver nanoparticles and evaluate their antimicrobial efficacy against human pathogens, Mycobacterium smegmatis and Candida albicans. Anisotropic silver nanoparticles were synthesized using silver nitrate as the metal precursor and gum arabic as the template. The synthesized silver nanoparticles were characterized by UV-visible spectroscopy, fourier transformation infra-red (FTIR) spectroscopy, dynamic light scattering (DLS) analysis, high-resolution transmission electron microscopy and selected area electron diffraction (HRTEM-SAED) analysis and thermogravimetric analysis (TGA). TEM analysis showed the anisotropy and monodispersed nature of silver nanoparticles with an average size of less than 20 nm. The antibacterial and antifungal properties of the anisotropic silver nanoparticles were also studied keeping rifampicin and fluconazole as the reference. The minimum inhibitory concentration (MIC) was found to be 1 mM silver nanoparticles for both M. smegmatis and C. albicans. Synthesized anisotropic silver nanoparticles can be used as an alternative to antibiotics to treat the infections caused by M. smegmatis and C. albicans. Further, the effect of silver nanoparticles on haemolytic activity was also studied. 2021 Wiley-VCH GmbH -
Hijab row verdict in India: A sentimental analysis of user responses on Facebook
The hijab controversy, a hot topic in India since January 2022, emerged from a clash between students and college authorities in Karnataka, a state in India. The dispute made its way to Karnatakas High Court, which, on 15 March 2022, ruled that the hijab was not mandatory for religious practices. This decision stirred widespread debates, especially on social media platforms like Facebook. This study is focused on user reactions in The Times of India Dailys official Facebook page, employing sentiment analysis to decipher public emotions, attitudes, and opinions. Nearly 200 comments posted on the verdict day were analyzed, utilizing the routine activity theory (RAT), spiral of silence theory, and online disinhibition effect. The research introduced a unique model, RAT+A, to enhance analysis. As a significant platform for public discourse, Facebook played a crucial role in capturing diverse societal sentiments and reactions regarding this social issue. 2025, First Monday. All rights reserved. -
Hike in student suicides Consequence of online classes?
[No abstract available] -
Hindu nationalism and media violence in news discourses in India
The mainstream media and communication discourses in India in the present times engender media violence embedded in the dominant productions of Hinduism together with aspirations for neoliberal development. The media violence engenders indigenous forms of racism and colonialism. This article attempts to examine the nature of these productions through critical theories of postcoloniality and decolonial approaches put into conversation with theories of journalism. Through the examination of the instances of selective silencing of journalistic voices, and erasures embedded within the journalistic practices, this article argues for critical theories of press freedom. The productions of racial superiority and internal colonialism in India only begin to make sense when read together with the interplays of religion, class, caste, and global reach of the privileged sections of Indian society, namely the civil society. Against the backdrop of the historical role of the press in India in freedom struggle against colonial rule, the history of press censorship after independence, the civil society voices that are amplified in the neoliberal restructuring of news media, and the Dalit movements that expose the Brahminical dominance in the imaginary of the Indian culture, the meanings of race and coloniality in India unfold. 2020 National Communication Association. -
Histopathological and Toxicological Studies on Zebra Fish Using White-Fruited and Green-Fruited Varieties of Momordica charantia
Momordica charantia is well known for its medicinal properties. It has exhibited various pharmacological activities, such as antidiabetic, anti-inflammatory, and antimicrobial activities. Although this plant is used worldwide as a vegetable and medicinal ingredient in herbal medicines, its toxicity studies have not been conducted to date. This study attempts to understand its toxicity. The present study examined the activity of two enzymes, acetylcholinesterase and succinate dehydrogenase, as well as histopathological variations in the liver, intestine, and gills of zebrafish. The results of the acetylcholinesterase assay showed that the concentrations of 40 mg/L and 60 mg/L of the four extracts (leaf and fruit extracts of both varieties) exhibited increased enzyme activity. Interestingly, the leaves of the green fruit variety at a concentration of 60 mg/L showed the highest activity, with a value of 2.824 0.0682 micromoles/min compared to the control value of 1.8347 0.0046 micromoles/min. On the other hand, the succinate dehydrogenase assay revealed that the concentrations of 40 mg/L and 60 mg/L of the extracts decreased the enzyme activity. The highest inhibition was observed in the concentration of 60 mg/L of the leaves of the white-fruited variety and the green-fruited variety, with values of 1.884 0.0482 micromoles/min compared to the control value of 2.747 0.0046 micromoles/min. The studies on histopathological changes also demonstrated abnormalities in the brain, liver, intestine, and gills of zebrafish after the exposure to the extracts of M. charantia. The severity of the damage varied from low to high concentraions. In general, this study sheds light on the safety profile of Momordica charantia and highlights its potential toxicity in animal models. The findings suggest that more research is needed to fully understand the toxicity of this plant and its implications for human use. 2024 Jobi Xavier et al. -
History of gestational diabetes mellitus, self-efficacy and coping in postpartum women: A pilot study
The present study investigates whether the history of gestational diabetes mellitus (GDM) influences self-efficacy and coping among postpartum women. Purposive sampling technique was used to collect data from 100 postpartum women, 50 with a history of GDM and 50 without. The General Perceived Self-Efficacy Scale was used to measure the self-efficacy of the participants. The Brief COPE developed by Carver was used to measure coping. A Mann-Whitney U-test showed postpartum women with a history of GDM are higher in self-efficacy and coping than those without such a history. Even though self-efficacy showed a relationship to coping, the two groups differed in the use of coping strategies. 2018 by the Research Institute of Asian Women, Sookmyung Women's University. All rights reserved. -
HIV-related stigma as a mediator between perceived social support and reasons for non-disclosure of self-HIV status among children and adolescents living with HIV
Children and adolescents living with HIV face complex decisions about disclosing their HIV status, influenced by social, emotional and contextual factors, including perceived support and experiences of stigma. This study examined the relationship between perceived social support, HIV-related stigma and motivations for non-disclosure, and assessed whether stigma mediates the link between social support and non-disclosure among young people living with HIV. A cross-sectional study was conducted with 90 participants aged 1018 years receiving antiretroviral therapy at a tertiary hospital in northern India. Participants completed standardized measures of perceived social support, HIV-related stigma and non-disclosure motivations. Higher social support was associated with lower stigma, and greater stigma predicted stronger non-disclosure motivation. Mediation analysis showed a significant indirect effect of social support on non-disclosure through stigma, indicating partial mediation. Findings underscore the central role of stigma in disclosure decision-making. Interventions that enhance supportive relationships and reduce stigmatizing attitudes in families, schools and healthcare settings may promote healthier coping and developmentally appropriate disclosure. 2026 Informa UK Limited, trading as Taylor & Francis Group. -
HMOSHSSA: a novel framework for solving simultaneous clustering and feature selection problems
In real-life scenarios, information about the number of clusters is unknown. Due to this, clustering algorithms are unable to generate the valuable partitions. Beside this, the appropriate and optimal number of features is also required to produce the good quality clusters. The selection of optimal number of clusters and feature is a challenging task in the clustering. To resolve these problems, an automatic multi-objective-based clustering approach called HMOSHSSA is proposed in this paper. In HMOSHSSA, the spotted hyena and salp swarm algorithms are hybridized to obtain a better trade-off between these algorithms intensification and diversification capabilities. Two novel concepts for encoding and threshold setting are incorporated in the HMOSHSSA. The encoding scheme is used to choose the optimal number of clusters and features during the optimization process. The variance of dataset is used for setting the threshold values for both clusters and features. A novel fitness function is proposed to improve the optimization process. The suggested algorithms performance is evaluated using eight well-known real-world datasets. The statistical significance of HMOSHSSA is measured through t-tests. Results reveal that the proposed approach is able to detect the optimal number of clusters and features from a given dataset without user intervention. This approach is also deployed for solving microarray data analysis and image segmentation problems. HMOSHSSA outperformed the other considered algorithms in terms of performance measures. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024. -
Hockey among the Indigenous Tribes of Sundargarh, Odisha
[No abstract available] -
Homestays as agents for responsible tourism: A comprehensive case study
The significance of implementing sustainable tourism practices has grown in light of the challenges of climate change and the diminishing availability of resources. Responsible tourism practices prioritize proactive engagement over mere adherence to sustainable practices. Therefore, the importance of responsibility cannot be overstated with the recovery and conservation efforts within the tourism sector. Responsibility should extend to the guests and encompass the environment, staff, and residents. Therefore, the present study aims to examine the potential for homestays to implement responsible tourist practices and maintain resilience. To accomplish the study's objective, an interview was conducted with a homestay owner in Shimla and Ratnari. Based on the author's understanding and the available literature on responsible tourism, there appears to be a dearth of studies about applying responsible tourism principles within the context of homestays. Therefore, the present study is of significant importance. 2024, IGI Global. All rights reserved. -
Homomorphic DNA Security in IoT Edge Data
The Internet of Things (IoT) based intelligent medical system possesses sensitive and private patient data. Most data relates to the patient's medical records and highly sensitive information. For this reason, safety and confidentiality of information are crucial. The preservation of patient privacy when sharing medical data is the primary concern of this study. Due to their excellent performance, biological notations based on deoxyribonucleic acid (DNA) are becoming increasingly admired for guaranteeing encryption and image protection. This paper proposes lightweight homomorphic with DNA-based medical image encryption (HDNA_MIE) for heterogeneous IoT in edge computing. The proposed approach contains two steps: In the first step, the secure DNA keys are generated using lightweight operations such as shifting and Josephus ring-based permutation (JRP). In the second step, the lightweight homomorphic cryptographic algorithm with DNA sequence-based encryption algorithm is suggested for secure encryption. The suggested strategy is evaluated using computational time and statistical analysis with several measures to determine its efficacy. The experimental findings of the proposed strategy exhibited a high level of security and a noticeable enhancement in the Number of Pixels Change Rate (NPCR), Unified Average Changing Intensity (UACI) and encryption processing time. The experiment outcomes demonstrate that our technique may be applied to highly confidential image encryption. 2024, Iquz Galaxy Publisher. All rights reserved.