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Polynomial time algorithm for inferring subclasses of parallel internal column contextual array languages
In [2,16] a new method of description of pictures of digitized rectangular arrays is introduced based on contextual grammars, called parallel internal contextual array grammars. In this paper, we pay our attention on parallel internal column contextual array grammars and observe that the languages generated by these grammars are not inferable from positive data only. We define two subclasses of parallel internal column contextual array languages, namely, k-uniform and strictly parallel internal column contextual languages which are incomparable and not disjoint classes and provide identification algorithms to learn these classes. Springer International Publishing AG 2017. -
Polymer-nanocarbon composites: a promising strategy for enhanced performance of organic solar cells
The exigency for sustainable and clean energy resources has led to profound research in development of various generations of solar cells, aiming to control the over-exploitation of fossil fuels and subsequently limit environmental degradation. Among the fast-emerging third-generation solar cells, polymer solar cell technology has gained much consideration due to its potential for achieving economically feasible, lightweight, flexible solar energy harvesting devices. As a predominant research area, at present, the major concerns regarding polymer solar cells include improving conversion efficiency, enhancing absorption bandgap in polymers, limiting photochemical degradation, and remediating low dielectric constant. Nanocarbon materials can be effectively blended with polymers and have been widely reported to enhance the performance of polymer solar cells owing to their desirable characteristics like high electrical conductivity, mechanical strength, thermal stability, non-toxicity, large specific surface area, flexibility, and optical transparency. In this review, we briefly discuss various conjugated polymer-nanocarbon composites, including polymer/graphene derivatives, polymer/graphene quantum dots (GQD), and polymer/carbon nanotubes (CNTs), elucidating their roles in the performance enhancement of polymer solar cells (PSCs). Graphical abstract: (Figure presented.). The Author(s) 2023. -
Polymer-Carbon nanocomposite: Synthesis, optical and biocidal properties
Microorganism contamination of food storage, water treatment, pharmaceuticals, and especially biomedical equipment is a severe problem. Bacteria frequently contaminate permanent implantations after long-term usage. To successfully treat these infections, it is essential to monitor microbial activity and know how it interacts with antibodies in real-time. In this work, a nanocarbon-polymer nanocomposite (ARPD) is successfully developed, and its antibacterial activity against selected microorganisms is successfully validated. Obtained antibacterial results confirm that the photoluminescent ARPD demonstrated outstanding antibacterial action against the microorganism Escherichia coli from the selected group of bacteria. The fluorescent diagnostics and treatments offer exciting possibilities for the luminescence and biocidal activity of nanocomposite produced from ARH-PVDF nanomaterials. 2023 The Author(s) -
Polymer-Based Nanomaterial as a Bacteriostatic Agent on Gram-Positive Bacteria
The colonization of surfaces by bacteria is a widespread phenomenon that affects environmental processes and human health. Bacterial growth can also be found in materials used in the textile industries, food packaging, and wearable electronics. Moreover, the necessity for replacing traditional antibiotics is relevant due to the increased health risks of antimicrobial resistance from the excessive use of antibiotics. Recently, research is focused more on developing polymer-based antibacterial materials critical to preventing bacterial proliferation. The use of some nanomaterials appears to be very promising in this regard. This work reports the synthesis of a polymer-based nanomaterial derived from polyvinyl alcohol (PVA) via the hydrothermal method and studies its structural and optical properties. It is also observed that these nanoparticles (NPs) display the highest antibacterial potency against gram-positive (Bacillus subtilis) bacteria than their bulk counterpart. 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. -
Polymer photosupercapacitors: combined nanoarchitectonics with polymer solar cell and supercapacitor for emerging powerpacks in next-generation energy applications
Efficient energy harvesting and storage are inevitable for the sustenance and growth of mankind, wherein the utilization of advanced technologies in this field has brought a significant impact on the energy sector. Integration of energy harvesting and storage devices is a need for powering next-generation energy needs like the Internet of Things (IoT), opening a wide range of application areas like wearable devices or integration with fabrics. Among third-generation solar cells, organic or polymer solar cells are extremely environment-friendly, lightweight, and flexible, making themselves potential candidates for integrated powerpacks along with supercapacitors. This article is a comprehensive review of polymer solar cell-based photosupercapacitors and their developments over the recent years. Through this review, we intend to give a valid account of polymer photosupercapacitors, to the scientific community regarding recent updates, which would help develop future approaches and strategies. As these integrated devices are considered to have a profound impact on energy industries and related applications, we believe that a detailed review of the present status and future prospects would aid further developments in the research field. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024. -
Polymer Nanocomposite Graphene Quantum Dots for High-Efficiency Ultraviolet Photodetector
Influence on photocurrent sensitivity of hydrothermally synthesized electrochemically active graphene quantum dots on conjugated polymer utilized for a novel single-layer device has been performed. Fabrications of high-performance ultraviolet photodetector by depositing the polypyrrole-graphene quantum dots (PPy-GQDs) active layer of the ITO electrode were exposed to an Ultraviolet (UV) source with 265 and 355 nm wavelengths for about 200 s, and we examined the time-dependent photoresponse. The excellent performance of GQDs was exploited as a light absorber, acting as an electron donor to improve the carrier concentration. PGC4 exhibits high photoresponsivity up to the 2.33 A/W at 6 V bias and the photocurrent changes from 2.9 to 18 A. The electrochemical measurement was studied using an electrochemical workstation. The cyclic voltammetry (CV) results show that the hysteresis loop is optically tunable with a UV light source with 265 and 355 nm at 0.1 to 0.5 V/s. The photocurrent response in PPy-GQDs devices may be applicable to optoelectronics devices. 2022 by the authors. -
Polyhydroxyalkanoate biosynthesis and characterization from optimized medium utilizing distillery effluent using Bacillus endophyticus MTCC 9021: a statistical approach
Use of expensive raw material and inefficient extraction method has limited the production of biopolymers at pilot scale compared to commercial plastics. Hence, this research work spotlights on production of polyhydroxyalkanoate (PHA) using Bacillus endophyticus MTCC 9021 in different dilutions of untreated distillery effluent (1025%) among which 10% dilutions exhibited maximum PHA production. Statistical optimization through Response surface methodology yielded a maximum PHA of 6.45 0.07 g/L. The obtained PHA was analysed by FTIR and NMR which confirms the polymer to be polyhydroxybutyrate. The extracted PHA was reduced to nanoscale to develop PHA nanosheet which exposed higher oil absorption and retention ability than normal PHA sheet. Further the rapid degradation of PHA nanosheet with synthetic plastics in garden soil emphasises their unique application in wide sectors. 2020, 2020 Informa UK Limited, trading as Taylor & Francis Group. -
Polycystic ovary syndrome: An exploration of unmarried women's knowledge and attitudes
Polycystic Ovary Syndrome (PCOS) is a common endocrine disorder among women of reproductive age and a chief cause of subfertility attributed to ovulation. Besides, lack of knowledge about PCOS, its treatment, and lifestyle changes influence the prognosis. The present qualitative inquiry investigates the knowledge and attitudes of unmarried women towards the syndrome, associated treatment, and necessary lifestyle changes in the fight against the same. A total of 15 participants with PCOS were selected using purposive sampling (n from southern parts of India viz. Kerala and Tamil Nadu states. The telephonic interviews were conducted in late November and early December 2020. He conventional content analysis emerged with six major themes. The themes capsulated women's knowledge, causes, complications and risk factors, treatment of PCOS their perceived importance of health promotive behaviours such as physical activity, sleep patterns, and perceived support from society. The importance of diet, exercise and a healthy lifestyle were additional relevant factors stressed by the respondents. Although the medicines helped participants attain regular menstrual cycles, they also had side effects reported in the discussion. Few respondents reported that they lacked the necessary awareness of PCOS when diagnosed at a younger age. The study enhances the understanding of PCOS from a qualitative approach that has cultural relevance apart from pertinent clinical and lifestyle implications. 2022 The Author(s) -
Polyaniline/Reduced Graphene Oxide/Zinc Oxide Hybrid Electrodes Fabricate by Combining Electrospinning/Electrospray Technique for Supercapacitors
This study presents the successful synthesis and characterization of polyaniline (PANI), PANI/reduced graphene oxide PANI/rGO (PR), and PANI/rGO/ZnO (PRZ) nanocomposites as electrode materials for supercapacitors. Employing electrospinning and electrospraying techniques, we developed nanofibrous composites with enhanced structural and electrochemical properties. The addition of rGO and ZnO in the PRZ composite significantly improved specific capacitance, stability, and charge-transfer efficiency. Electrochemical analyses, including cyclic voltammetry (CV), galvanostatic chargedischarge (GCD), and electrochemical impedance spectroscopy (EIS), revealed a peak specific capacitance of 845 F g?1 at 0.5 A g?1 for PRZ, outperforming PR (395 F g?1), and PANI (140 F g?1). These enhancements are attributed to the synergistic effects of carbon-based and pseudocapacitive components, resulting in higher conductivity, improved redox activity, and reduced internal resistance. Additionally, the PRZ composite exhibited excellent cyclic stability, retaining 89% of its capacitance over 5000 cycles, underscoring its durability and suitability for long-term energy storage applications. 2024 John Wiley & Sons Ltd. -
Polyamines influence the production of Boeravinone-B from cell suspension cultures of Boerhavia diffusa L.
Boerhavia diffusa L. (Punarnava) is an ayurvedic herb with a wide range of phytochemicals and pharmacological activities that have been utilised since antiquity. Boeravinone-B (an isoflavone rotenoid molecule) is one of the most significant secondary metabolites produced in its plant body. Modern plant biotechnological tools have helped in the overproduction of desired plant secondary metabolites from in vitro cell and organ cultures. Elicitation is one such strategy employed for the production of phytochemicals. In the present study, polyamines like putrescine, spermine and spermidine have been used as elicitors for the production of Boeravinone-B. The cell suspension cultures of punarnava have been treated with polyamines at various concentrations, ranging from 0.5 to 20M, at various day intervals of 2, 4 and 6 before the harvesting. The fresh weights, dry weights of cell suspension cultures, their Boeravinone-B content and yield are evaluated. Among all the various polyamine treatments, 2.5M spermidine (SPD) on the 6th day before harvesting shows the highest Boeravinone-B content of 10.88 0.13mgg?1 DW and yield of 110.34mg L?1 respectively, which is a five-fold increment compared to the control cultures (2.16 0.06mgg?1 DW and 16.35mg L?1) respectively. The highest total phenolic content in the cell suspension cultures is observed with 1?M SPD on the 2nd day prior to harvesting (194.25 0.37mgg?1 DW), while the highest levels of flavonoids are observed with 2.5?M SPD on the 6th day before harvesting (86.85 0.26mgg?1 DW). 2023, The Author(s), under exclusive licence to Springer Nature B.V. -
Poly(vinyl alcohol)bismuth oxide composites for X-ray and ?-ray shielding applications
Polymer composites, which are light in weight, cost effective, and less toxic, have potential applications in X-ray and ?-ray shielding and protection. In this work, we have explored the efficacy of poly(vinyl alcohol)bismuth oxide composites as radiation shielding materials. Poly(vinyl alcohol) composites with different wt % (050) of bismuth were prepared by a simple solution casting technique. Structural and thermal characterization of these samples was carried out using Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). TGA revealed the enhanced thermal stability of these composites. AC conductivity measurements and optical spectroscopy were used to analyze their electrical behavior. The composites showed low conductivity, and the energy gap obtained also showed their tendency to be insulators. The radiation attenuation properties were investigated using X-ray (5.895 and 6.490 keV) and ?-ray (59.54 and 662 keV) transmission measurements. The shielding efficiency of the composites increased with filler wt %. The 40 wt % composites exhibited mass attenuation coefficients of 122.68 and 93.02 cm2/g at photon energies of 5.895 and 6.490 keV, respectively, while the 50 wt % composites showed 1.57 and 0.092 cm2/g at photon energies of 59.54 and 662 keV, respectively. The effective atomic number quantifies the probability of interaction of radiation with matter. The effective atomic number of the composites calculated by the direct method was in good agreement with the theoretical value obtained from Auto-Zeff software. 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47949. 2019 Wiley Periodicals, Inc. -
Poly(aniline) decorated with nanocactus platinum on carbon fiber paper and its electrocatalytic behavior toward toluene oxidation
Electrochemically deposited polymeric film of polyaniline (PANI) is used as a substrate for electrochemical deposition of platinum by using cyclic voltammetry. The electrochemical properties of multi-layered films were analyzed by cyclic voltammetry and AC impedance spectroscopy. The structural properties of multi-layered polymer films were analyzed by SEM, TEM, XRD, XPS, Raman and FTIR. The modified electrode showed strong electrocatalytic activity toward oxidation of toluene in presence of NaNO 2 /H 2 SO 4 in actetonitrile medium. Toluene gave a sensitive anodic peak at 1.318 V (vs. SCE). Cyclic voltammetry studies suggest that the electrochemical activity of Pt-PANI/CFP electrode is higher than that of Pt/CFP electrode toward toluene oxidation. 2018 The Electrochemical Society. -
Pollution Haven Hypothesis and the Bilateral Trade Between India and China
The pollution haven hypothesis is studied from a bilateral trade perspective in this study, taking the reference of two Asian giants, namely, India and China. For this purpose, trade in pollution-intensive industries is analysed using data collected from the United Nations Comtrade dataset based on Standard Industrial Trade Classification codes for 19922019. The analysis helps us argue that between the two, China's demand is more pollution-intensive and India is the major supplier of pollution-intensive products. From an environmental perspective, this implies that China seems to be gaining from trade, and India is becoming a pollution haven in its trade with China. The Author(s) 2023. -
Pollution forecast of united states using holt-winter exponential method
The United States is the world's most developed country and one of the top ten most air polluted countries in the world. Though the population is not very dense as in India or China, people face immense health problems. The US government is taking a lot of initiatives than any other government globally. However, it still faces issues. This paper mainly focuses on developing a forecasting model of the top four pollutants like SO2, NO2, CO, O3 that will help the country take necessary actions for the near future. This paper involves the secondary data of the daily pollution collected and merged for all states from 2007 to 2017. The forecast will throw the better output at the pollutants for the next four years, until 2021. The findings revealed that despite the increased GDP, the country had controlled the pollution level. NO2 has decreased to a better level. O3 and CO2 are also decreasing but has slight fluctuations. It will take some time to stabilize. SO2 had an increased level till 2017 and has started reducing afterwards. 2021 Ecological Society of India. All rights reserved. -
Political Representation of Mumbai Political Representation of Mumbai in Rohinton Mistrys Such a Long Journey and A Fine Balance
The representation of cities in works of literature is significant as it is these images of cities which are consumed throughout the world. The objective of this thesis is to examine the Political Representation of Mumbai in Rohinton Mistrys Such a Long Journey and A Fine Balance. I have used Stuart Halls essay The Work of Representation as the theoretical framework for analysing the two selected works of fiction. I have analysed representation in the two texts by applying the semiotic approach to representation; by studying the contextual major political events, characters and spaces in the city as signs which are encoded by the author in the texts to construct the city of Mumbai. It was found that the author encodes Such a Long Journey with the political representation of Mumbai as ??a city in siege, as ??a city in throes of conspiracy and as ??a city of struggle, squalor, pleasure, nostalgia, loss, spirituality and political power struggles and thus constructs the city of Mumbai in this novel . Moreover, the political representation of Mumbai in A Fine Balance is done by employing signs like Mumbai as ??a city grappling with a draconic state and its life-denying laws, Mumbai as ??an all-embracing and redemptive city and of Mumbai as ??a city great in its magnanimity but also great in its inadequacies. Thus, Mistry constructs Mumbai which is the signifying field on which Emergency politics are played out in the novel. -
Political propaganda portrayed in Hindi films /
Politics being one of the central object in democratic and highly politicize country like India has its impact and influence on every walk of life of this country. Since the beginning of the 20th century cinema in many ways has influenced social consciousness and helped in shaping our inner understanding. Both cinema & politics become important aspects of our society. It is important to study how they interact and how cinema adopt or take shape via political discourse of this country. -
Political Optimizer-Based Optimal Integration of Soft Open Points and Renewable Sources for Improving Resilience in Radial Distribution System
A novel and simple meta-heuristic optimization technique viz., political optimizer (PO) is proposed in this paper to identify the size and optimal location of solar photovoltaic (SPV) system. The main objective is to minimize the distribution loss and is solved using proposed PO. The computational efficiency of PO is compared with the literature, and its superiority is highlighted in terms of global solution at initial stage. The physical requirements of SPV system via soft open points (SOPs) among multiple laterals are solved considering radiality constraints in second stage. The proposed concept of interoperable-photovoltaic (I-PV) system has been applied on standard IEEE 69-bus system and has shown the effectiveness in performance enhancement of the system. 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. -
Political Optimizer Algorithm for Optimal Location and Sizing of Photovoltaic Distribution Generation in Electrical Distribution Network
In this paper, the political optimizer (PO), a new and efficient socio-inspired meta-heuristic search algorithm, is proposed for the first time in this research for determining the ideal locations and capacities of photovoltaic (PV) distribution generation (DG) in electrical distribution networks (EDN). A multi-objective function is designed to lower distribution losses and voltage deviation indexes and maximize voltage stability, among other objectives. The computational efficiency of PO when solving the optimal allocation of PV systems in EDN is investigated on an IEEE 33-bus EDN. The results indicate that integrating small DGs at multiple locations has a better EDN performance than integrating a single significant DG in the network. The results also suggest that, as demonstrated by a comparative analysis of PO results and those of other related literature works, PO can deal with complex multi-variable optimization problems. 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. -
Policies and metrics for schedulers in cloud data-centers using CloudSim simulator
Todays cloud technology consumers must address escalating computing and storage demands for services and applications. However, decision-making on provisioning and scheduling is challenging due to varying workflow demands within Infrastructure as a Service (IaaS). This study formulates an optimization problem with multiple objectives to identify optimal policies, employing heuristic metrics through cloud simulation similar to AWS EC2 instances. Experiments involve two task scheduler types, time-shared and space-shared, aimed at minimizing execution time and cost. The study introduces two novel algorithms, SLB and MinMax, for comparison with standard algorithms. It emphasizes the importance of precise quantification of uncertainty in cloud storage allocation and highlights the state-of-the-art policies and metrics achieved through virtualization techniques. The studys novelty lies in simulating both policies at two levels and proposing a novel algorithm for multi-objective optimization while providing cost and time measurements. Contributions include experimenting with various combinations, applying heuristics to entire data center entities, proposing a novel algorithm, and offering cost and time measurements for the optimizations. 2023, The Author(s), under exclusive licence to Springer Nature Switzerland AG. -
Polarity detection on real-time news data using opinion mining
Sentimental Analysis or Opinion Mining plays a vital role in the experimentation field that determines the users opinions, emotions and sentiments concealing a text. News on the Internet is becoming vast, and it is drawing attention and has reached the point of adequately affecting political and social realities. The popular way of checking online content, i.e. manual knowledge-based on the facts, is practically impossible because of the enormous amount of data that has now generated online. The issue can address by using Machine Learning Algorithms and Artificial Intelligence. One of the Machine Learning techniques used in this is Naive Bayes classifier. In this paper, the polarity of the news article determined whether the given news article is a positive, negative or neutral Naive Bayes Classifier, which works well with NLP (Natural Language problems) used for many purposes. It is a family of probabilistic algorithms that used to identify a word from a given text. In this, we calculate the probability of each word in a given text. Using Bayes theorem, they are getting the probabilities based on the given conditions. Topic Modeling is analytical modelling for finding the abstract of topics from a cluster of documents. Latent Dirichlet Allocation (LDA) is a topic model is used to classify the text in a given document to a specified topic. The news article is classified as positive or negative or neutral using Naive Bayes classifier by calculating the probabilities of each word from a given news article. By using topic modelling (LDA), topics of articles are detected and record data separately. The calculation of the overall sentiment of a chosen topic from different newspapers from previously recorded data done. 2020 The authors and IOS Press.