Symmetry properties of tetraammine platinum(II) with C_(2v) and C_(4v) point groups

INTRODUCTION The simplicity and elegance of some of theapplications of graph theory to chemistry can perhapsonly be compared with the results from group theorydealing with symmetry as a basic quality of a system.In some problems connectivity and symmetry arecombined and the question of determining symmetryproperties of graph becomes important. Given here are some definitions and notations.An automorphism of a graph G is a permutation g ofthe vertex set of G with the property that, for an…     

The COVID‐19 (Coronavirus) pandemic: reflections on the roles of librarians and information professionals

This Regular Feature explores the role of health science librarians in the coronavirus pandemic. COVID‐19 has spread rapidly all over the world. All major cities around the globe are in lockdown. In Pakistan, the first case was diagnosed on 26 February 2020, and currently, there are more than 2039 diagnosed cases and 26 deaths as on 31 March 2020. Across the country, there are further 12 000 suspected cases. This will undoubtedly increase if precautionary measures are not taken. Pakistani universities, colleges and schools were in lockdown. The role of university librarians in this emergency included raising awareness through public health education, providing support to medical staff, researchers and providing ongoing traditional services to regular library patrons in Pakistan. The Regular Feature also provides links to useful resources. JM.     

The role of gestures in the mathematical practices of those who do not see with their eyes

In this paper, we aim to contribute to the discussion of the role of the human body and of the concrete artefacts and signs created by humankind in the constitution of meanings for mathematical practices. We argue that cognition is both embodied and situated in the activities through which it occurs and that mathematics learning involves the appropriation of practices associated with the sets of artefacts that have historically come to represent the body of knowledge we call mathematics. This process of appropriation involves a coordination of a variety of the semiotic resources??spoken and written languages, mathematical representation systems, drawings, gestures and the like??through which mathematical objects and relationships might be experienced and expressed. To highlight the connections between perceptual activities and cultural concepts in the meanings associated with this process, we concentrate on learners who do not have access to the visual field. More specifically, we present three examples of gesture use in the practices of blind mathematics students??all involving the exploration of geometrical objects and relationships. On the basis of our analysis of these examples, we argue that gestures are illustrative of imagined reenactions of previously experienced activities and that they emerge in instructional situations as embodied abstractions, serving a central role in the sense-making practices associated with the appropriation of mathematical meanings.     

Exploring design features to enhance computer‐based assessment: Learners' views on using a confidence‐indicator tool and computer‐based feedback

Many institutions encourage formative computer‐based assessment (CBA), yet competing priorities mean that learners are necessarily selective about what they engage in. So how can we motivate them to engage? Can we facilitate learners to take more control of shaping their learning experience? To explore this, the Learning with Interactive Assessment (LINA) project, a small‐scale study, trialed a selection of online, interactive question features designed to increase motivation, particularly of work‐based learners, and to enhance learners' ability to self‐regulate their own learning experience. We present initial findings on learner perceptions of: (1) a confidence indicator tool—for learners to indicate their confidence that their answer will be correct before answering a question; (2) a learning log—for learners to insert reflections or view system‐recorded information about their learning pathway; and (3) question feedback—for displaying a range of author comments. Themes emerged relating to motivational, behavioural and cognitive factors, including risk taking and skills in self‐assessment. A serendipitous finding highlights learners' frequently not reading onscreen feedback and presents perceptions on when feedback becomes most useful. Motivators and barriers to engagement and self‐regulation are discussed in relation to principles of best feedback practice.     

Cytotoxicity and Apoptosis Inducing Activities of 2-Amino-4H-chromene-3-carbonitrile Derivatives Loaded on Gold Nanoparticles Against Human Breast Cancer Cell Line T47D

Chemotherapy drugs, used for prevention of uncontrolled cell proliferation in certain tissues as well as inducing apoptosis in tumor cells, are important candidates for treatment of cancer. The synthesized 2-amino-4H-chromene-3-carbonitrile derivatives effective on cancerous cells resistant to other drugs such as Paclitaxel were used due to their ability in induction of apoptosis. The growth inhibitory and inducing apoptosis activities were determined. In order to make it target-oriented, the best compound was conjugated with gold nanoparticles (NPs) by aspartic acid with chemical reduction method. Cytotoxicity effect of 2-amino-4H-chromene-3-carbonitrile derivatives against the T47D breast cancer cell line was determined by MTT assay. The synthesis of gold NPs was confirmed by transmission electron microscopy, UV–Vis and dynamic light scattering. To assess the effects of compounds on the process of apoptosis, staining methods with acridine orange–ethidium bromide and Hoechst staining by fluorescence microscopy and DNA fragmentation by the diphenylamine method were used. The synthesized compounds containing two NH₂ groups on benzene rings, demonstrated more cytotoxicity effect. The effect of conjugation with gold NPs and the induction of apoptosis were studied with the best compound. The cytotoxicity effects of the synthesized 2-amino-4H-chromene-3-carbonitrile compounds were changed by replacement of NO₂ group on thiol ring with different chemical groups on the benzene ring. Analyses of treated cell lines by conjugated and non-conjugated forms of compounds verified their ability in inducing apoptosis while conjugated form demonstrated higher apoptosis.     

A cross‐cultural examination of the impact of social,organisational and individual factors on educational technology acceptance between British and Lebanese university students

This paper examines the social, organisational and individual factors that may affect students' acceptance of e‐learning systems in higher education in a cross‐cultural context. A questionnaire was developed based on an extended technology acceptance model (TAM). A total sample of 1173 university students from two private universities in Lebanon and one university in England participated in this study. After performing the satisfactory reliability and validity checks, the hypothesised model was estimated using structural equation modeling. The findings of this study revealed that perceived usefulness (PU), perceived ease of use (PEOU), social norms (SNs), perceived quality of work life (QWL), computer self‐efficacy (SE) and facilitating conditions (FC) are significant determinants of behavioural intentions (BIs) and usage of e‐learning system for the Lebanese and British students. QWL, the newly added variable, was found the most important construct in explaining the causal process in the model for both samples. Differences were found between Lebanese and British students with regard to PEOU, SN, QWL, FC, SE and actual usage; however, no differences were detected in terms of PU and BI. Overall, the proposed model achieves acceptable fit and explains for 69% of the British sample and 57% of the Lebanese sample of its variance which is higher than that of the original TAM. Our findings suggest that individual, social and organisational factors are important to consider in explaining students' BI and usage of e‐learning environments.     

The Rise of Modern Sport in Fin de Siècle São Paulo: Reading Elite and Bourgeois Sensibilities,the Popular Press,and the Creation of Cultural Capital

In the period between 1890 and 1910, British sport flourished in a rapidly modernizing Brazilian city. São Paulo boomed as a coffee export centre for the global market, growing into the second largest metropolis in Brazil. New businesses and industries developed and thousands of immigrants from around the world migrated to the expanding South American city. Along with the flow of new residents came new ideas, new attitudes, and new lifestyles. British sporting customs particularly attracted the attention of São Paulo’s wealthy elites and expanding middle classes who saw in these habits the potential to advertize their commitment to modern ideals of civilization and order. The new British-style sporting clubs that sprang up in São Paulo conferred the cultural capital that the leadership castes needed to gain and maintain their hegemony in the city’s rapidly changing social landscape. São Paulo’s press circulated these new sensibilities and revealed that the city’s sporting enthusiasts both reproduced Westernized norms and re-signified athletic sensibilities to fit Brazilian social patterns.     

Renovation of Adult Education by the New Media

In most developing countries, that are confronted, as we know, with so many complex problems, no one can deny that the most important are those of education and training.     

Graduated compression stockings: physiological and perceptual responses during and after exercise

The aim of this study was to examine the effect of wearing graduated compression stockings on physiological and perceptual variables during and after intermittent (Experiment 1) and continuous (Experiment 2) running exercise. Fourteen recreational runners performed two multi-stage intermittent shuttle running tests with 1 h recovery between tests (Experiment 1). A further 14 participants performed a fast-paced continuous 10-km road run (Experiment 2). Participants wore commercially available knee-length graduated compression stockings (pressure at ankle 18 - 22 mmHg) beneath ankle-length sports socks (experimental trials) or just the latter (control trials) in a randomized counterbalanced design (for both experiments). No performance or physiological differences were observed between conditions during intermittent shuttle running. During the 10-km trials, there was a reduction in delayed-onset muscle soreness 24 h after exercise when wearing graduated compression stockings (P < 0.05). There was a marked difference in the frequency and location of soreness: two participants in the stockings trial but 13 participants in the control trial indicated soreness in the lower legs. Wearing graduated compression stockings during a 10-km road run appears to reduce delayed-onset muscle soreness after exercise in recreationally active men.