Interesting Class Research Articles

Fault-Tolerant Metric Dimension of Barycentric Subdivision of Cayley Graphs

Metric dimension and fault-tolerant metric dimension of any graph G is subject to size of resolving set. It has become more important in modern GPS and sensors based world as resolving set ensures that in case of semi outage system is still scalable using redundant interfaces. Metric dimension of several interesting classes of graphs have been investigated like Cayley digraphs, Cartesian product of graphs, wheel graphs, convex polytopes and certain networks for categorical product of graphs. In this paper we used the phenomena of barycentric subdivision of graph and proved that fault-tolerant metric dimension of barycentric subdivision of Cayley graph is constant.

Ambient pressure synthesis and structure and magnetic properties of a new A- and B-site ordered multinary quadruple perovskite.

Quadruple perovskites with high magnetic transition temperatures are an interesting class of compounds but are synthesized typically under high pressure. Ambient pressure synthesis of new multinary quadruple perovskites having a high global instability index (GII) and transition temperature can be interesting for future exploration of high-TC oxides. A new A- and B-site ordered multinary quadruple perovskite, LaCu3Fe2RuSbO12, is synthesized by conventional solid-state reactions at ambient pressure. Rietveld structure refinement revealed that the compound crystallizes in the Pn3̄ space group with a lattice parameter of 7.4556(4) Å. The compound showed complete 1 : 3 ordering of La and Cu at the A-site and 1 : 1 rock-salt ordering of Fe with Ru/Sb at the B-site. The compound is also probed with scanning and transmission electron microscopy and XPS to investigate the chemical composition, microstructure, lattice and oxidation states of the elements. Magnetic studies revealed antiferromagnetic (AFM) correlations with magnetic ordering transitions at ∼170 and 40 K. Furthermore, the M-H hysteretic behavior at 100 and 5 K indicated ferrimagnetism due to short-range AFM interactions among Fe3+(3d5) and Ru4+(4d4) spins involving Cu2+(↑)-Fe3+(↓)-Ru4+(↑) triads. The specific heat data reaffirmed the magnetic signatures while electrical transport showed semiconducting behavior with variable range hopping. The details of synthesis and structural and compositional studies along with the magnetic and electrical transport properties of LaCu3Fe2RuSbO12 are reported in this paper.

A Review Article on Migrane

Migrane are a neurological disorder characterized by recurrent, moderate to severe headache. They are often accompanied by symptoms such as nausea, vomiting, sensitivity to light and sound and in some cases, visual disturbances migraines can significantly impact a person’s quality of life and may require a combination of lifestyles changes, medication and other therapies for effective management. Migraine is the sixth most prevalent disease globally, a major cause of disability, and it imposes an enormous personal and socio-economic burden. Migraine treatment is often limited by insufficient therapy response, leading to the need for individually adjusted treatment. In this review, we analyse historical and current pharmaceutical development approaches in acute and chronic migraine based on comprehensive and systematic analysis of Food and Drug Administration (FDA)-approved drugs and those under investigation. The development of migraine therapeutics has significantly intensified during the last 3 years, as shown by our analysis of the trends of drug development between 1970 and 2020. The spectrum of drug targets has expanded considerably, which has been accompanied by an increase in the number of specialised clinical trials. This review highlights the mechanistic implications of FDA approved and currently investigated drugs and discusses current and future therapeutic options based on identified drug classes of interest.

An Analysis of EFL Students' Communication Strategies in Classroom Context

This study aims to find out the types of communication strategies used by EFL students when learning English in the 12th grade English Cross Interest class at SMAN 5 Bantaeng. This study used descriptive qualitative method, data were collected through observation and interviews conducted with 4 students. Data came from three sources: namely audio recordings of naturally occurring classroom interactions; interviews with students and observation notes taken in the classroom. Data from the interaction transcripts were examined using Dorney & Scott's (1997) taxonomy of communication strategies.The results of this study show that there are five types of communication strategies that most often appear when students communicate with their interlocutors as well as towards their teachers during learning activities, namely; Message Abandonment, Non-Linguistic Means, Filler, Appeal For Help and Asking For Clarification. The students used L1 because the students found it difficult to understand L2. This is due to the fact that students lack knowledge of English. Students experience these types of communication strategies due to thinking time, anxiety, lack of focus, nervousness, doubt, lack of knowledge, lack of vocabulary, grammatical errors and self-confidence.

Teacher's experience on the use of Computer Technology in Teaching Mathematics in Public Secondary Schools in Nakuru Town Sub-Counties, Kenya

Classroom experience helps a teacher to understand the teaching environment. Effectiveness in instilling knowledge in students is through gaining experience in teaching. Teaching experience can be explained as a state of developing skills, training, and exposure that enables a professional teacher to be more effective while instructing. Classroom experience helps a teacher to understand the teaching environment. Effectiveness in instilling knowledge in students is through gaining experience in teaching. The use of computer technology enables a teacher to gain practical knowledge on actively engaging learners and establishing an interesting class experience. Despite this, teacher years of experience were found to be negatively associated with the amount of instruction especially when using technology with less experienced teachers achieving significantly higher scores. Existing literature shows that Computer Technology can enhance instruction if basic conditions of teacher experience are met. This paper establishes the efficacy of teachers' experience with the use of computer technology in teaching Mathematics This study employed descriptive research design. A sample of 10 Mathematics teachers, 10 Principals, and one CQASO was used. The data was collected using questionnaires and Lesson observation tools and interview schedules. Data collected was analyzed and presented in, frequencies, means, percentages, and tables. Qualitative data were analyzed thematically, transcribed, organized, and reported in a verbatim form where the researcher captured the spoken words of respondents during an interview while maintaining the exact words used. The findings show that the use of Computer Technology in the Teaching of Mathematics is more done by less experienced teachers.

IgMAT: immunoglobulin sequence multi-species annotation tool for any species including those with incomplete antibody annotation or unusual characteristics

BackgroundThe advent and continual improvement of high-throughput sequencing technologies has made immunoglobulin repertoire sequencing accessible and informative regardless of study species. However, to fully map dynamic changes in polyclonal responses precise framework and complementarity determining region annotation of rearranging genes is pivotal. Most sequence annotation tools are designed primarily for use with human and mouse antibody sequences which use databases with fixed species lists, applying very specific assumptions which select against unique structural characteristics. For this reason, data agnostic tools able to learn from presented data can be very useful with new species or with novel datasets.ResultsWe have developed IgMAT, which utilises a reduced amino acid alphabet, that incorporates multiple HMM alignments into a single consensus to automatically annotate immunoglobulin sequences from most organisms. Additionally, the software allows the incorporation of user defined databases to better represent the species and/or antibody class of interest. To demonstrate the accuracy and utility of IgMAT, we present analysis of sequences extracted from structural data and immunoglobulin sequence datasets from several different species.ConclusionsIgMAT is fully open-sourced and freely available on GitHub (https://github.com/TPI-Immunogenetics/igmat) for download under GPLv3 license. It can be used as a CLI application or as a python module to be integrated in custom scripts.

Soliton molecules in Fermi–Pasta–Ulam–Tsingou lattice: Gardner equation approach

We revisit the Fermi–Pasta–Ulam–Tsingou lattice (FPUT) with quadratic and cubic nonlinear interactions in the continuous limit by deducing the Gardner equation. Through the Hirota bilinear method, the fundamental as well as multi-soliton, particularly two-, three- and four-soliton, solutions are obtained for the Gardner equation. Based on these multi-soliton solutions, we show the excitation of an interesting class of table-top soliton molecules in the FPUT lattice through the velocity resonance mechanism. Depending on the condition on the free parameters, which determine the bond length between the soliton atoms, we classify them as dissociated and synthetic type molecules. The main feature of the table-top soliton molecules is that they do not exhibit oscillations in the coalescence region. This property ensures that they are distinct from the soliton molecules, having retrieval force, of the nonlinear Schrödinger family of systems. Further, to study the stability of the soliton molecule we allow it to interact with a single (or multi) soliton(s). The asymptotic analysis shows that their structures remain constant, though the bond length varies, throughout the collision process. Then, from the relative separation distance calculation we also observe that the bond length of each of the soliton molecules is not maintained during soliton molecule–molecule interaction while their structures are preserved. In addition, we consider the FPUT lattice with quadratic nonlinear interaction and FPUT lattice with cubic nonlinearity as sub-cases and point out the nature of the soliton molecules for these cases also systematically. We achieve this based on the interconnections between the solutions of the Gardner, modified Korteweg–de Vries and Korteweg–de Vries equations. Finally, in order to validate the existence of all the soliton structures, especially reported for the Gardner equation in the continuous limit, we simulate the corresponding FPUT chain and verified these various structures numerically and analytically as well. We believe that the present study can be extended to other integrable and non-integrable systems with applications in fluid dynamics, Bose–Einstein condensates, nonlinear optics, and plasma physics.

First-order logic with metric betweenness – the case of non-definability of some graph classes

The metric betweenness of a connected graph and arbitrary graphs is FO definable. Moreover, several interesting classes of graphs with strong distance properties are shown to be FO definable using metric betweenness. However, there are different classes that do not possess such an FO axiomatization. The main goal of this note is to show that certain classes of graphs do not allow an axiomatization in First-Order Logic with Betweenness (FOLB).

Chimeras-States in the Distributed Systems in the Case of Multi-Valued Solutions. To the Statement of Possible Research Problems

Nonlinear science has about a hundred years of rapid development. One of the new directions is the study of chimera solutions, i.e. solutions that exhibit significantly different solution behaviour in different regions of space or time. Just a few examples of such behavior have been studied in different systems. However, all examples of chimeras have been single-valued solutions. Recently, however, many nonlinear models of physical and social phenomena have multivalued solutions. It is conceivable that one of the possible directions for further research in chimera science is to allow multivalued solutions to be considered. The paper is devoted to describing some possible research settings in this area. Some modifications of existing models are also proposed. The interesting class of such objects is the models with strong anticipation (models with advanced arguments). Furthermore, some problems of computational theory and mind with such models are discussed.

Sustainability Education for Trainee Teachers: Landscape and Mirror Classes as Educational Tools

Under the sustainability education paradigm, the landscape has a key role as an identity object of study in the interaction between nature and society. This research is motivated by a practical experience with trainee teachers on the systematized analysis of local degraded landscapes in Spain. This study is based on environmental, sustainability, and global citizenship literacies—the guarantors of sustainability education. A mirror class methodology was implemented with the objective of evaluating the effectiveness of sustainability learning and the influence of students’ personal factors. A quasi-experimental methodology was followed through a didactic and statistical analysis of student reports and a validated questionnaire. The findings reveal a 2.9/4 global didactic evaluation, one that is higher in didactic tasks and lower in comparative ones, and a statistically significant learning acquisition of +0.8. The results suggest that the study of local landscapes captures interest and mirror classes bring distant realities closer, thus achieving a successful eco-social education and didactic transfer.

End‐/side‐chain fluorescent polymer conjugates: Stimuli‐responsiveness and biological applications

AbstractSmart fluorescent polymers are an interesting class of advanced materials that find widespread applications in diverse areas ranging from materials chemistry to biology. This review highlights the last 15 years' developments of end‐chain and side‐chain fluorescent polymer conjugates by employing various controlled polymerization techniques, with a major focus on “grafting to” or “grafting from” strategies. The fluorescent polymer conjugates that discussed in this review are limited to some conventional dye molecules such as perylene‐3,4,9,10,‐bis(dicarboximide), 1,8‐naphthalimide, tetraphenylethylene, azo dye, rhodamine, coumarin, fluorescein, pyrene, and a few other selected dyes. Attempts are also made to primarily describe the changes in optical properties of these conjugates in response to various external stimuli. Additionally, this review extensively discusses the formation of nanoassemblies of these fluorescent polymer conjugates, along with their various applications, majorly focusing on their role in bioimaging, drug delivery, and DNA binding.

Transition Metal Triple-decker Sandwich Complexes Containing Group 13 Elements.

Transition metal triple-decker complexes are an interesting class of sandwich complexes that engrossed great attention due to their structures and properties. Over the decades, synthesis of triple-decker complexes featuring homocyclic, heterocyclic or π-conjugated rings as middle decks have been abundantly reported. In this regard, the chemistry of such complexes bearing boron in the middle deck are well explored due to the ability of boron-containing cycles to readily coordinate bifacially with metal atoms thereby forming triple-decker complexes. On the other hand, electron counting rules and theoretical calculations have strengthened our knowledge of the structure and bonding in these complexes. Further, these complexes can be used as synthons to generate organometallic polymers having interesting electronic, optical and magnetic properties that can be appropriately tuned to cater to a wide range of applications. In our quest for novel metallaboranes and metallaheteroboranes, we have been successful in isolating various triple-decker complexes that feature boron in the middle deck. This review explained elaborately the synthesis, structures, and bonding in such complexes reported by us and others.

Self-Assembly of Atomically Precise Silver Nanoclusters in Crowded Colloids into Ultra-Long Ribbons with Tunable Supramolecular Chirality.

Atomically precise metal nanoclusters (NCs) emerge as fascinating synthons in self-assembled materials. The self-assembly of metal NCs are highly sensitive to the environment because they have an inorganic-organic hybridized structure and a relatively complicated conformation. Here, it is shown that when confined in crowded colloids, a water-soluble Ag9 -cored nanocluster (Ag9 -NC) can self- assemble into ultra-long (up to millimeters) and photoluminescent ribbons with high flexibility. The ribbon contains rectangularly organized columns of Ag9 -NCs and can undergo secondary self-assembly to form bundled and branched structures. Formation of ribbons is observed in all the tested colloids, including lyotropic liquid crystals and disordered, three-dimensional network. The high viscosity/elasticity of the crowded colloids weakens gravity-induced sedimentation of the ribbons, leading to the formation of an interesting class of inorganic-organic composite materials where the hard Ag-containing skeleton strengthens the soft matter. The simultaneously occurring symmetry breaking during the self-assembly of Ag9 -NCs gives uncontrolled supramolecular chirality, which can be tuned through the majority rule and soldier-and-sergeant rule by the introduction of chiral seeds. The regulated chirality and the intrinsic photoluminescence of the Ag9 -NCs ribbons impart the composite material circularly polarized luminescence, opening the door for a variety of potential applications.

In situ mechanical testing of hard yet tough high entropy nitride coatings deposited on compliant steel substrates

High entropy nitrides are an interesting material class for wear resistant coatings. Their fracture properties and toughness are of particular interest for future application in tool coatings. Therefore, in situ tensile testing and micro-cantilever experiments were performed on (AlCrTaTiZr)N, (AlCrNbSiTiV)N, (HfNbTaTiVZr)N and (AlTi)N coatings inside a scanning electron microscope. Parallel cracks form during tensile testing from which the fracture toughness was determined via a modified Hsueh and Yanaka model. For this the misfit strain between coating and substrate was treated as an unknown parameter and was fitted to the beginning part of the underlying crack density – applied strain curves. The validity of the model was evaluated by comparing the results with fracture toughness values derived via micro-cantilever bending experiments. A good fit between the data could be observed for three out of four tested coatings. The limitations of the underlying analytical model are presented and discussed. The tested high entropy nitride coatings displayed a promising combination of high hardness and fracture toughness.

Concerning Fuzzy b-Metric Spaces †

In an article published in 2015, Hussain et al. introduced a notion of a fuzzy b-metric space and obtained some fixed point theorems for this kind of space. Shortly thereafter, Nădăban presented a notion of a fuzzy b-metric space that is slightly different from the one given by Hussain et al., and explored some of its topological properties. Related to Nădăban’s study, Sedghi and Shobe, Saadati, and Šostak independently conducted investigations in articles published in 2012, 2015, and 2018, respectively, about another class of spaces that Sedgi and Shobe called b-fuzzy metric spaces, Saadati, fuzzy metric type spaces, and Šostak, fuzzy k-metric spaces. The main contributions of our paper are the following: First, we propose a notion of fuzzy b-metric space that encompasses and unifies the aforementioned types of spaces. Our approach, which is based on Gabriec’s notion of a fuzzy metric space, allows us to simultaneously cover two interesting classes of spaces, namely, the 01-fuzzy b-metric spaces and the K-stationary fuzzy b-metric spaces. Second, we show that each fuzzy b-metric space, in our sense, admits uniformity with a countable base. From this fact, we derive, among other consequences, that the topology induced by means of its “open” balls is metrizable. Finally, we obtain a characterization of complete fuzzy b-metric spaces with the help of a fixed point result which is also proved here. In support of our approach, several examples, including an application to a type of difference equations, are discussed.

Modelling of Intelligent Object Detection and Classification using Aquila Optimizer with Deep Learning on Surveillance Videos

Object Detection (OD) in surveillance video is the way of automatically detecting and tracking object classes of interest within the video recording. It includes the application of a Computer Vision (CV) technique to analyze the video frame and identify the classes of objects or the presence of specific objects. Various OD techniques are used to find objects within the footage video. This algorithm analyzes the visual feature of the frames and employs Machine Learning (ML) approaches namely Deep Neural Network (DNN), to detect and track objects. It is worth mentioning that the accuracy and performance of OD in surveillance video depends on factors including the choice of algorithms and models, the availability of labelled training data, and the quality of the video frame for the specific object of interest. This study introduces a new modeling of Intelligent Object Recognition and Classification by employing Aquila Optimizer with Deep Learning (IODC-AODL) approach in Surveillance Video. The goal of the IODC-AODL technique is to integrate the DL model with the hyperparameter tuning process for object detection and classification. In the proposed IODC-AODL approach, a Faster RCNN method is enforced for the process of OD. Next, Long Short-Term Memory (LSTM) networking approach is implemented for the object classification process. At last, the AO approach is enforced for the optimum hyperparameter tuning of the LSTM network and it assists in improving the classifier rate. A widespread simulation sets are performed to exhibit the superior performance of the IODC-AODL approach. The experimental result analysis portrayed the supremacy of the IODC-AODL algorithm over other models.

Some inequalities for two simplices in the Euclidean space En

Simplices are used as building blocks to construct an interesting class of topological spaces called simplicial complexes, which exhibit remarkable symmetric properties. In this paper, we study the problems of inequalities for two simplices in the Euclidean space En. We establish some new inequalities for the vertex distances of two simplices and obtain some generalizations of the classical Neuberg-Pedoe inequality.

Perceptions and Satisfaction Level of Learners in Online General Education during the COVID-19 Era : A Case Study of K University

This study investigated the perceptions and satisfaction level of learners regarding online general education at K University during the COVID-19 pandemic in 2020 and 2021. The research aimed to analyze the changes in learners' perceptions and level of satisfaction. The summarized findings of the study are as follows: First, compared to 2020, the level of overall satisfaction among students with online general education classes increased in 2021, and learners' perceptions improved. However, their satisfaction with instructors' feedback and interesting class structures remained low. Second, there was an increased intention on the part of students to enroll in online general education courses, but the intention was lower for liberal arts practicum courses. Student satisfaction with online general courses in the performing arts field was lower compared to humanities and STEM (Science, Technology, Enginerring, Mathematics) fields. Third, learners reported an improvement in their online learning environments. However, addressing the digital information gap and supporting students with disabilities require consideration. Fourth, learners preferred pre-recorded lectures, and meeting their demands through features like recording functions and additional videos in real-time video lectures was necessary. Fifth, similar to 2020, learners identified assignment burdens, difficulties in practical courses, and communication issues with instructors as disadvantages of online liberal arts education. Sixth, in both 2020 and 2021, learners recognized that instructors' delivery skills and their interest and enthusiasm in online classes were the most crucial factors in enhancing the quality of online liberal arts education. Based on these findings, implications for the future direction and improvement of online liberal arts education were proposed, along with suggestions for further research.

A Fitting Definition of Epistemic Emotions

Abstract Philosophers and psychologists sometimes categorize emotions like surprise and curiosity as specifically epistemic. Is there some reasonably unified and interesting class of emotions here? If so, what unifies it? This paper proposes and defends an evaluative account of epistemic emotions: What it is to be an epistemic emotion is to have fittingness conditions that distinctively involve some epistemic evaluation. We argue that this view has significant advantages over alternative proposals and is a promising way to identify a limited and interesting class of emotions.

Synthesis and analytical characterization of Ca-BTC metal organic framework

Metal Organic framework (MOF) has been a class of great interest during the past few years owing to its decidedly applicative, easily synthesized and improved characteristics. Ca-BTC MOF is synthesized by Hydrothermal technique and reported for the first time. Its structural morphology was analyzed using XRD, SEM, and EDS, showing the tetragonal crystal structure having grain size of 24.92 nm and purity of sample respectively. FTIR, Raman Spectroscopy ensures the metal organic framework between Calcium and the tri-carboxylic group. Photoluminescence measures the energy gap of 3.792 eV, showing approximately the semiconducting behavior of synthesized material. Zeta potential having value of −13.5 mV confirms the instability having good microbial activity and conductivity i.e 0.290 mS/cm which reveals important insights into its electrical properties.