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Human behavior analysis of BBC-news comments posted on facebook using lexicon-rule based approach
Today people spend a considerable part of their time on online platforms say, social media than with the real world. Social media, particularly Facebook is the platform for the users to post, share, like, tag and comment any photos and videos. This paper deals with the Facebook platform to study the human behavior based on the comments of five posts from BBC-news Facebook page. For every post in Facebook we can get different opinion or emotional behavior by different users. The behavior of people to the same event need not be similar, they can be different. A response through comments and smileys for a post portrays behaviors of people. Here the behavior analysis is performed on comments of the BBC news Facebook posts. The comments of the post are fetched by the online extractor named Socialfy [12]. This paper considered five news from unique from BBC-news Facebook page. The human behavior analysis performed using Python VADER (Valence Aware Dictionary and Sentiment Reasoner) package. This work uses the Lexicon approach to assign scores for the words and rule-based approach used to find the polarity type of words. The polarity of a post is the sentimental behavior of the people towards the post. The total polarity of this work tends towards neutral so, we could conclude that for each situation behavior of man can take positive or negative poles. 2019, Institute of Advanced Scientific Research, Inc. All rights reserved. -
Classification, source, and effect of environmental pollutants and their biodegradation
Any foreign chemical substance that is unusually present within an organism or is unexpectedly found in the environment at a higher concentration than the permissible limits can be termed a xenobiotic or a pollutant. Such substances include carcinogens, drugs, food additives, hydrocarbons, dioxins, polychlorinated biphenyls, pesticides or even some natural compounds. Pollutants are known for their higher persistence and pervasiveness, and along with their transformed products, they can remain in and interact with the environment for prolonged periods. In this article, the classification of such substances based on their nature, use, physical state, pathophysiological effects, and sources is discussed. The effects of pollutants on the environment, their biotransformation in terms of bioaccumulation, and the different types of remediation such as in situ and ex situ remediation, are also presented. 2017 Begell House, Inc. -
Composites based on natural polymers
Polymers are composed of macromolecules of high molecular weight formed by the repeated union of small molecules known as monomers. Polymer materials over other materials such as metals and ceramics, are of light weight and hence extensively used. The use of renewable raw materials can provide a substantial activity for a sustainable society and environment. Natural polymer composites can provide an alternative to increasingly scarce raw materials from plants and animals. 2017 Nova Science Publishers, Inc. -
Role of Bioadsorbents in Reducing Toxic Metals
Industrialization and urbanization have led to the release of increasing amounts of heavy metals into the environment. Metal ion contamination of drinking water and waste water is a serious ongoing problem especially with high toxic metals such as lead and cadmium and less toxic metals such as copper and zinc. Several biological materials have attracted many researchers and scientists as they offer both cheap and effective removal of heavy metals from waste water. Therefore it is urgent to study and explore all possible sources of agrobased inexpensive adsorbents for their feasibility in the removal of heavy metals. The objective was to study inexpensive adsorbents like various agricultural wastes such as sugarcane bagasse, rice husk, oil palm shell, coconut shell, and coconut husk in eliminating heavy metals from waste water and their utilization possibilities based on our research and literature survey. It also shows the significance of developing and evaluating new potential biosorbents in the near future with higher adsorption capacity and greater reusable options. 2016 Blessy Baby Mathew et al. -
Accumulation of lead (Pb II) metal ions by Bacillus toyonensis SCE1 species, innate to industrial-area ground water and nanoparticle synthesis
Groundwater samples were collected from Peenya Industrial area of Bengaluru, India to check its inherent bacterial population. After the isolates were grown in lead-induced media, the bacteria that could resist lead were further isolated, identified, and grown. The isolated bacterium was identified as Bacillus toyonensis SCE1 species, and the maximum amount of lead taken up by it to sustain itself as a live biomass was 8ppm. Lead accumulation was studied based on different factors such as pH, concentration, and time. Bacterial characterization through scanning electron microscopy showed there was lead sorption on the bacterial cells. Transmission electron microscopy revealed that accumulated lead ions inside the bacteria were in the range of 180190nm, this was found to correlate with the data obtained by the particle size analyzer. The optimum pH for highest lead accumulation was 7.2, for a time period of 160min. It was observed that the stable production of homogenous nanoparticles using biomass could be achieved by optimizing factors such as incubation period, agitation, pH, temperature, and contact time. 2018, Springer-Verlag GmbH Germany, part of Springer Nature. -
Excitation Mechanism of Oi Lines in Herbig Ae/Be Stars
We have investigated the role of a few prominent excitation mechanisms viz. collisional excitation, recombination, continuum fluorescence, and Lyman beta fluorescence on the O i line spectra in Herbig Ae/Be stars. The aim is to understand which of them is the central mechanism that explains the observed O i line strengths. The study is based on an analysis of the observed optical spectra of 62 Herbig Ae/Be stars and near-infrared spectra of 17 Herbig Ae/Be stars. The strong correlation observed between the line fluxes of O i ?8446 and O i ?11287, as well as a high positive correlation between the line strengths of O i ?8446 and H? suggest that Lyman beta fluorescence is the dominant excitation mechanism for the formation of O i emission lines in Herbig Ae/Be stars. Furthermore, from an analysis of the emission line fluxes of O i ??7774, 8446, and comparing the line ratios with those predicted by theoretical models, we assessed the contribution of collisional excitation in the formation of O i emission lines. 2018 The American Astronomical Society. All rights reserved.. -
Spectroscopic Study Of Selected Be Stars In Our Galaxy
The optical spectroscopic monitoring observation of two Be stars namely 4 Hercules and 88 Hercules was observed with 1.02m telescope at the VBO, Tamil Nadu, India over a period of six months. The spectra were reduced using standard routines in IRAF. The equivalent width of the lines were identified have been measured. The line profile variability exhibited by H? H?and HeI lines are studied to understand the emission mechanism in the Classical Be-stars. The properties of the process can be well constrained, leaving only few options, most importantly, but not exclusively, non-radial pulsation and small scale magnetic fields. In different stars different processes may be acting. This is not only true for the disk structure, but as well for its variability, both cyclic and secular. Be stars, at lower metallicities, seem more common and more rapidly rotating. The Be phenomenon, linked with one or more mass ejection processes, acts on top of a rotation rate of about 75% of critical or above. In this work, first the definition of Be-stars is contrasted to similar classes, and common observables obtaind for Be-stars are introduced and the respective formation mechanism explained. The current state of knowledge concerning the central stars as non-radially pulsating objects and non-magnetic stars, as far as it concerns large scale. The weak magnetic fields remain possible, but are of yet unproven. In this dissertation Chapter 1 discusses the features of Be- stars and reviewed the progress made in understanding Be-stars in the recent past. Chapter 2 discusses the literature review. Chapter 3 describes the methodology carried out to study the objective. Chapter 4 explains the result and analysis part of the research. Chapter 5 is about the conclusions. -
An aqueous phase TEMPO mediated electrooxidation of 2-thiophenemethanol using MnO2-Pi dispersed nanocarbon spheres on a carbon fiber paper electrode
An environmentally benign and economic method was developed for the electrocatalytic oxidation of 2-thiophenemethanol in an aqueous acidic medium. Nanocarbon spheres (NCS) coated on carbon fiber paper (CFP) were used as a host matrix to disperse manganese dioxide nanoparticles from phosphate buffer solution through electrochemical deposition. The developed electrode (MnO2-Pi-NCS/CFP) was used as a working electrode for electrochemical oxidation of 2-thiophenemethanol in the presence of a mediator TEMPO in 0.01 M H2SO4 medium. Different analytical methods were used to characterize the modified electrodes. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to study the electrochemical properties of the modified electrodes. The electrochemically active surface area values calculated for bare CFP, NCS coated CFP and MnO2-Pi-NCS/CFP electrodes were found to be 1.43 cm2, 2.86 cm2, and 6.72 cm2 respectively for the geometric area of 0.7 cm2 of the electrodes. Coating of NCS and MnO2-Pi resulted in porosity and roughness of the CFP electrode which enhances the surface area. MnO2-Pi-NCS/CFP demonstrated higher electrocatalytic activity for oxidation of 2-thiophenemethanol to 2-thiophenemethanal in aqueous acidic media with a TEMPO mediator compared to unmodified electrodes. This journal is 2021 The Royal Society of Chemistry. -
MnO2-Pi on biomass derived porous carbon for electro-catalytic oxidation of pyridyl carbinol
A facile electrochemical oxidation of pyridyl carbinol based on Manganese dioxide-Phosphate (MnO2-Pi) was fabricated by electro-deposition of MnO2-Pi on Porous carbon nanospheres (PCN) modified carbon fiber paper (CFP) electrode. A simple working electrode was developed initially by coating Monkey Pod (MP) derived PCN on carbon fiber paper (CFP) electrode. Voltammetric deposition of MnO2-Pi on PCN/CFP electrode was carried out in an electrolyte containing phosphate buffer and KMnO4. The modified electrodes (PCN/CFP and MnO2-Pi-PCN/CFP) were characterized by different physicochemical methods and electroanalytical techniques like cyclic voltammetry and AC impedance spectroscopy. Inorganic phosphate (Pi) and MnO2 centers present on PCN/CFP electrode plays a major role towards oxidation of pyridyl carbinol electrochemically. The proposed MnO2-Pi-PCN/CFP electrode was effectively applied for the electrochemical oxidation of pyridyl carbinol in TEMPO medium. 2020 The Author(s). -
TEMPO mediated electrocatalytic oxidation of pyridyl carbinol using palladium nanoparticles dispersed on biomass derived porous nanoparticles
Remarkable electrocatalytic property of Pd nanostructures dispersed on CNSareca coated CFP electrode towards TEMPO mediated electrooxidation of pyridyl carbinol was reported for the first time. Carbon nanospheres (CNSs) derived from Areca catechu decorated with Pd nanoparticles were coated on carbon fiber paper (CFP) and was employed for electrooxidation of pyridyl carbinol in aqueous acidic medium. An environmentally benign and economic strategy was utilized for the preparation of CNSs obtained from Areca catechu. The physical characterizations, electronic state and chemical composition of the modified electrode were studied using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) spectroscopy and X-ray photoelectron spectroscopy (XPS). Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM) techniques were used for analyzing the morphology of modified electrode. The electrochemical characterizations of the modified electrodes were performed by Cyclic voltammetry (CV) and Electrochemical impedance spectroscopy (EIS). Pd decorated CNSareca dispersed on CFP electrode has exhibited strong electrocatalytic activity towards TEMPO mediated oxidation of pyridyl carbinol. 2020 Elsevier Ltd -
TEMPO-Mediated Aqueous Phase Electrooxidation of Pyridyl Methanol at Palladium-Decorated PANI on Carbon Fiber Paper Electrode
Palladium nanoparticles decorated on polyaniline coated carbon fiber paper electrode (Pd-PANI/CFP) was employed for TEMPO ((2,2,6,6-tetramethylpiperidin-1-yl)oxyl) mediated electrocatalytic oxidation of pyridyl methanol to pyridyl carboxaldehyde using cyclic voltammetry in aqueous acidic media using a surfactant. The electrochemical properties of the modified electrodes were studied by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The physicochemical properties of the modified electrodes were studied using Scanning electron microscopy (SEM) with Energy dispersive X-ray spectroscopy (EDS), Transmission electron microscopy (TEM), Optical profilometry, X-ray diffraction (XRD) spectroscopy, Raman spectroscopy and Fourier transform infrared (FTIR) spectroscopy. Pd-PANI/CFP electrode has exhibited enhanced electrocatalytic activity towards TEMPO mediated oxidation of pyridyl methanol owing to higher electrochemically active surface area of the modified electrode. CV studies suggested higher electrochemical activity for Pd-PANI/CFP electrode when compared to PANI/CFP and bare CFP electrodes towards TEMPO mediated oxidation of pyridyl methanol. 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim -
TEMPO mediated electrochemical oxidation of 4-pyridinemethanol using Pd and Pt Co-deposited polyaniline modified carbon fiber paper
Co-deposition of palladium and platinum (PdPt) nanoparticles on the conducting polymeric ?lm of Polyaniline (PAn) modified carbon fiber paper (CFP) electrode was carried out by using eletrochemical method. The modified electrode has been used for the oxidation of 4-pyridinemethanol. The electrochemical properties of fabricated multi-layered ?lms on carbon fiber paper (Pd-Pt/PAn/CFP) were studied by electrochemical AC impedance spectroscopy and cyclic voltammetry (CV). Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) characterization technics were environmentally benign and sustainable are used to analyze the structural properties of modified multi-layered electrode. The relative sizes and distribution of the nanoparticles on the electrode surface were analyzed using Scanning electron microscopy (SEM) and optical profilometry characterization techniques. Electrochemical studies by CV showed that the PdPt/PAn/CFP electrode had better electrochemical activity similar to PAn/CFP and Bare CFP electrode towards extensive electrochemical oxidation of 4-pyridinemethanol in presence of TEMPO (2,2,6,6-Tetramethylpiperidinyl-1-oxyl) in aqueous acidic medium. 2021 -
NLP-based personal learning assistant for school education
Computer-based knowledge and computation systems are becoming major sources of leverage for multiple industry segments. Hence, educational systems and learning processes across the world are on the cusp of a major digital transformation. This paper seeks to explore the concept of an artificial intelligence and natural language processing (NLP) based intelligent tutoring system (ITS) in the context of computer education in primary and secondary schools. One of the components of an ITS is a learning assistant, which can enable students to seek assistance as and when they need, wherever they are. As part of this research, a pilot prototype chatbot was developed, to serve as a learning assistant for the subject Scratch (Scratch is a graphical utility used to teach school children the concepts of programming). By the use of an open source natural language understanding (NLU) or NLP library, and a slack-based UI, student queries were input to the chatbot, to get the sought explanation as the answer. Through a two-stage testing process, the chat-bot's NLP extraction and information retrieval performance were evaluated. The testing results showed that the ontology modelling for such a learning assistant was done relatively accurately, and shows its potential to be pursued as a cloud-based solution in future. 2021 Institute of Advanced Engineering and Science. All rights reserved. -
GCMS analysis, anthelmintic, antibacterial and antifungal properties of unripe fruit peel extract of Musa paradisiaca L.
Endoparasites, namely, Ascaris sp., Taenia sp., Haemonchus contortus, Ancylostoma duodenale etc. are of serious concern since they can lead to financial loss if farm animals are attacked by these parasites. Finding out cost-effective natural remedies for these infections is an area of research in the field of veterinary sciences. The current study was undertaken with a view to explore the anthelmintic property of banana peel along with its other bioactive properties. The fruit is available abundantly throughout the year and the peel is often discarded as waste. This study has shown that the extracts of the Nendran variety of Musa paradisiaca L. fruit peel have potent anthelmintic, antibacterial and antifungal activities. Preliminary cytotoxicity studies have also given positive results. GCMS analysis has revealed the major phytochemicals responsible for the bioactive properties of the peel. Since the United Nations has urged countries to align research and development with a thrust on sustainable development, these kinds of natural alternatives are best suited in place of synthetic drugs. 2023 World Research Association. All rights reserved. -
Exploring the anti-inflammatory activities, mechanism of action and prospective drug delivery systems of tocotrienol to target neurodegenerative diseases
A major cause of death in the elderly worldwide is attributed to neurodegenerative diseases, such as AD (Alzheimers disease), PD (Parkinsons disease), ALS (Amyotrophic lateral sclerosis), FRDA (Friedreichs ataxia), VaD (Vascular dementia) etc. These can be caused due to multiple factors such as genetic, physiological problems like stroke or tumor, or even external causes like viruses, toxins, or chemicals. T3s (tocotrienols) exhibit various bioactive properties where it acts as an antioxidant, anti-inflammatory, anti-tumorigenic, and cholesterol lowering agent. Since T3 interferes with and influences several anti-inflammatory mechanisms, it aids in combating inflammatory responses that lead to disease progression. T3s are found to have a profound neuroprotective ability, however, due to their poor oral bioavailability, their full potential could not be exploited. Hence there is a need to explore other drug delivery techniques, especially focusing on aspects of nanotechnology. In this review paper we explore the anti-inflammatory mechanisms of T3 to apply it in the treatment of neurodegenerative diseases and also discusses the possibilities of nano methods of administering tocotrienols to target neurodegenerative diseases. Copyright: 2023 Mathew AM et al. -
State of the art MOF-composites and MXene-composites: Synthesis, fabrication and diverse applications
The composites of MXene and Metal-organic frameworks (MOFs) have gained considerable attention recently due to their synergic properties. MOFs are advantageous as it offers high surface area, good stability, and tunable chemical structure, MXenes, on the other hand, provide superior ion-transport characteristics, high conductivity, large surface-to-volume ratio, and facile modification strategies. Composite fabrication enables tuning the desired properties of the individual materials and propounds good stability and enhanced performance. This review assembles and describes the composites of MXene and MOF in various fields of application like energy storage devices, sensors, medicinal, separation membranes, medicinal, and photocatalysis in a comprehensible way. Here we first outline the characteristics of MOFs and MXenes along with a comparative study of different synthesis routes for the fabrication of the composites. The review also encompasses a detailed discussion on different industries and applications that the MXene and MOF composites are subjected to. Finally, the review provides future perspective for designing and development of newer composites as well as scope for further industrial approach. 2024 Elsevier Ltd -
Facile Synthesis of Polymer Dot and Its Antibacterial Action Against Staphylococcus aureus
Antimicrobial resistance (AMR) rising from nosocomial infections is an escalating threat to human life nowadays due to the overuse of drugs. The multidrug-resistant pathogenic bacteria have increased morbidity and mortality rates, becoming a crucial global clinical challenge. Gram-positive Staphylococcus aureus bacteria is one of the nosocomial pathogens that cause severe invasive diseases and skin infections to human health worldwide. Herein, a non-conjugated polymer dot (NCPD) was synthesized from less toxic and biocompatible polyvinyl alcohol (PVA) via hydrothermal treatment. The fluorescence of the polymer dots was enhanced by nitrogen doping. The as-synthesized nitrogen-doped polymer dots (PDs) exhibit excitation-dependent luminescence emission and show green color fluorescence under UV light. The average size of the synthesized functionalized non-conjugated polymer dot is obtained as 4.08nm, and they exhibit an amorphous structure. No antibacterial property was observed for bulk polymer, but the doped polymer dots showed antibacterial activity against Gram-positive Staphylococcus aureus bacteria. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd 2024. -
A Review on Recent Trends in Biological Applications of Non-conjugated Polymer Dots
With the advancement of zero-dimensional carbon materials, carbon dots (CDs) have received immense attention owing to their exceptional optical properties, tailoring of size, and ease of functionalization. They have wide applications in fluorescent sensing, chemical sensing, bioimaging, photocatalysis, etc. Zero-dimensional polymer nanoparticles are called polymer dots (PDs) and are classified into conjugated and non-conjugated PDs based on their conjugated system. Non-conjugated polymer dots (NCPDs) do not have specific conjugated fluorophore groups, but they have superior chemical stability and water solubility than the conjugated PDs. The carbon core of NCPDs is surrounded by polymer chains containing ample functional groups such as C=O, N=O, and C=N, which are responsible for the luminescent PDs. NCPDs are less toxic, photostable, and biocompatible and are relevant in biological explorations in bioimaging, drug delivery, biosensing, etc. This mini-review provides a systematic overview of the inherent properties and the biological applications of NCPDs. It also emphasises the synergistic impacts on the optical performance of modified PDs and significant future research concerns. Graphical Abstract: [Figure not available: see fulltext.]. 2023, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
Fluorescent PVDF dots: from synthesis to biocidal activity
Infection by microorganisms is a serious concern in food storage, water purification, drugs, and particularly in biomedical devices. Long-term use of permanent implants often leads to its contamination due to pathogens. Timely tracking of bacterial activity and its interaction with antibodies are crucial for overcoming these infections. In this work, fluorescent polymeric biocides are obtained from a non-conjugated polymer polyvinylidene fluoride (PVDF), which is neither emissive nor known for its antibacterial activity. PVDF dot was synthesized via hydrothermal treatment eliminating the need for complicated and toxic preparation strategies. PVDF-based dot exhibits high fluorescence aroused from the carbogenic core due to the carbonization of the hydrocarbon chain. It is found that the dots were semiconducting contrary to the bulk form of PVDF. The photoluminescent polymer dots also exhibited an excellent antibacterial activity toward Escherichia coli (E.coli) and Streptococcus bacteria. This luminescence and biocidal activity of PVDF-derived dots have attractive applications in the field of fluorescent diagnostics and therapeutics. Graphical abstract: [Figure not available: see fulltext.] 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature. -
Comprehensive understanding of biomedical usages of metal and non metal doped carbon dots
In recent years, carbon dots have garnered significant attention, particularly within the biomedical realm, owing to their exceptional characteristics. The unique attributes of carbon dots can be further enhanced through the introduction of heteroatom via doping. Various techniques have been devised by researchers to facilitate the doping of carbon dots, with both metallic and non-metallic elements. Elements such as nitrogen (81%), sulfur (67%), and silicon (64.1%) have been successfully employed for doping carbon dots leading to heightened quantum yields. This review compiles the diverse methodologies and elements employed in doping of carbon dots, and their applications in the biomedical domain in recent times. This review discusses the uses of doped carbon dots, both metal and non-metal-doped variants, elucidating their manifold utilities in various biomedical sectors, notably bioimaging, wound healing, and cancer therapy. The discussion culminates by addressing present challenges and offering insights into future prospects of doped carbon dots. 2023 Elsevier Ltd