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There has been an expanding public interest towards the notion that modulation of the sophisticated endocannabinoid system can lead to various therapeutic benefits that are yet to be fully explored. In recent years, the drug discovery paradigm in this field has been largely based on the development of selective CB2 receptor agonists, avoiding the unwanted CB1 receptor-mediated psychoactive side effects. Mechanistically, target engagement studies are crucial for confirming the ligand-receptor interaction and the subsequent biological cascades that lead to the observed therapeutic effects. Concurrently, imaging techniques for visualisation of cannabinoid receptors are increasingly reported in the literature. Small molecule imaging tools ranging from phytocannabinoids such as tetrahydrocannabinol (THC) and cannabidiol (CBD) to the endocannabinoids as well as the purely synthetic cannabimimetics, have been explored to date with varying degrees of success. This Review will cover currently known photoactivatable, electrophilic, and fluorescent ligands for both the CB1 and CB2 receptors. Structural insights from techniques such as ligand-assisted protein structure (LAPS) and the discovery of novel allosteric modulators are significant additions for better understanding of the endocannabinoid system. There has also been a plethora of fluorescent conjugates that have been assessed for their binding to cannabinoid receptors as well as their potential for cellular imaging. More recently, bifunctional probes containing either fluorophores or electrophilic tags are becoming more prevalent in the literature. Collectively, these molecular tools are invaluable in demonstrating target engagement within the human endocannabinoid system.

Engineering degree programmes include a significant amount of practical work for which national accrediting bodies stipulate a set of laboratory-learning outcomes. This paper sets out to understand how students’ interactions in the laboratory contribute to the attainment of laboratory-learning outcomes. The investigation was conducted in the traditional face-to-face laboratory mode. Results from surveys of final-year students and instructors are reported. Students’ and instructors’ perspectives of the relative importance of four main types of student interaction to meet each of the Engineers Australia laboratory-learning outcomes are also presented. Students primarily expected to interact with instructors more than with students (directly or through observation of interactions) or equipment for their achievement of the learning outcomes, whereas instructors reported that all of the interactions are important to achieve the learning outcomes.

Immersive Virtual Reality (VR) is increasingly being used as an educational tool to help students visualise complex structures and phenomena. The use of VR is particularly useful for science animation that involves sub-microscopic and abstract processes in a 3D environment, such as the interactions of molecules, electrons and forces. However, few research studies have explored how immersive VR can support science visualisation compared to existing tools, notably computer animation on a flat screen. The study in this chapter used a semiotic perspective to examine the multimodal affordances of a ‘virtual’ mode of representation made possible by VR technology. The study involved the design and development of a VR animation to show the structure and reaction of an enzyme called acetylcholinesterase. A group of chemistry undergraduates was recruited to take part in a learning activity using the VR animation in pairs. Based on an analysis of the learners interacting with the VR animation, this chapter reports on the affordances of VR compared to other tools in five specific areas: viewing, sequencing, modelling, scaling and manipulating. Through the use of case studies, it also illustrates and discusses how these affordances facilitate student learning of molecular interactions.

© 2020, Springer Nature B.V. This paper describes the development, final design and validation of an instrument that measures a range of student interactions and satisfaction in undergraduate chemistry laboratories. Student surveys or conceptual and attitudinal instruments are widely used techniques for collecting relevant information on student learning. However, there is a lack of specific instruments for collecting data on the relationships between social factors and learning. Consequently, this study attempted to fill this gap by introducing an instrument—the Interactions in Undergraduate Laboratory Classes (IULC). The design of the IULC instrument is based on the theory of distributed cognition, meaning that knowledge is not rooted in an individual’s mind, but develops in the process of interacting with the environment. The instrument covers three aspects: (i) frequency of interactions, (ii) satisfaction and (iii) importance of interactions for the specific laboratory. Undergraduate students (N = 204) enrolled in a first-year chemistry course participated in a test case for the instrument and the corresponding data were analysed using different methods for each of the three parts. The factor structure of the data obtained from the first part of the instrument and internal consistency measures are discussed. Among findings captured by the instrument, student-teacher (instructors in the university context) interactions correlated positively with students’ satisfaction levels. Implications and suggestions for the use of the instrument are discussed.

Our interest in the potential of chiral tetramethoxy-resorcinarene as agents for chiral recognition has led us to synthesise twelve distally-bridged chiral resorcinarene crowns. The fascinating architecture of these partially-enclosed chiral basket molecules is evident in the solid-state structures which have been determined by single crystal X-ray crystallography. Moreover, the enantiomers of these chiral resorcinarene crowns have been resolved via diastereomeric resolution, with the absolute configuration of the diastereomers being determined by X-ray crystallography. This work enables further exploration of these enantio-pure chiral baskets as possible chiral resolving agents.

This paper reviews the ways in which interactions have been studied, and the findings of such studies, in science education in both face-to-face and remote laboratories. Guided by a systematic selection process, 27 directly relevant articles were analysed based on three categories: the instruments used for measuring interactions, the research findings on student interactions, and the theoretical frameworks used in the studies of student interactions. In face-to-face laboratories, instruments for measuring interactions and the characterisation of the nature of interactions were prominent. For remote laboratories, the analysis of direct interactions was found to be lacking. Instead, studies of remote laboratories were mainly concerned with their practical scope. In addition, it is found that only a limited number of theoretical frameworks have been developed and applied in the research design. Existent theories are summarised and possible theoretical frameworks that may be implemented in studies of interactions in undergraduate laboratories are proposed. Finally, future directions for research on the interrelationship between student interactions and laboratory learning are suggested.

© 2019 Informa UK Limited, trading as Taylor & Francis Group. Investigations into the distal-functionalisation of the phenols of racemic C4-symmetric tetramethoxyresorcinarene has led to a simple, single-step procedure that allows the isolation of gram quantities of partially silylated derivatives, with the targeted distally silylated resorcinarene being obtained in a yield of 31%. These partially silylated derivatives would serve as versatile intermediates for the selective functionalisation of this elegant architecture. The solid-state structures of many of these derivatives have been determined by single crystal X-ray crystallography.

Computer-aided visualisation has played an essential role in helping students construct a better understanding of molecular interactions over the years but it has limitations in supporting 3D visualisation, especially for complex molecules. As an alternative platform, immersive virtual reality (VR) holds great promise for addressing students' difficulties. This paper examines the educational possibilities and limitations of immersive VR environments.

© 2018 The Royal Society of Chemistry. Laboratories play a crucial role in the undergraduate science curriculum and the effectiveness of learning in laboratories is influenced by learners' interactions with other students, the instructors, and the equipment used. In this study, a pre-lab survey was used to collect information about students' expectations of interactions in chemistry laboratories and how they can be ranked according to their importance. Post-lab surveys were used to capture students' perspectives about the frequency of interactions that existed in laboratory sessions they had completed. Direct observations of some laboratories were also conducted principally to validate students' self-reported interactions. The data were also sorted by three levels of student achievement in order to relate students' expectations of the importance of different interactions (pre-lab survey) and their self-reported frequency of interactions (post-lab survey) with their laboratory grades. Results from the pre-lab survey showed that student-instructor interactions were anticipated to be the most important ahead of conducting the laboratory activity, whereas results from the post-lab surveys showed that the most frequent interactions occurred between students. Students' self-reports (post-lab survey) and the direct observations agreed well suggesting that the post-lab survey is a robust tool for capturing the frequencies of student interactions in this and future studies. The results also showed that students gaining high grades both anticipated the importance of, and then engaged more frequently in, two-way communications with both students and instructors whereas students with lower grades placed a relatively higher reliance upon passive interactions such as the pre-lab briefing, the laboratory manual and internet sources. Finally, recommendations are offered to curriculum designers, instructors and students based on the overall findings of the study.

A follow-up study was conducted with foundation-year chemistry students who were taught in an inquiry- and role-based, small-group active learning environment in order to evaluate their attitudes, experiences and self-efficacy during pre-medical chemistry courses. The study adopted a mixedmethods research design that involved both experimental and comparison groups. Using the CAEQ (Chemistry Attitudes and Experiences Questionnaire) and the ASCI v2 (Attitude toward the Study of Chemistry Inventory), the findings of this study indicated that inquiry-based chemistry learning experience improves the students’ intellectual accessibility and emotional satisfaction as well as develops their self-efficacy levels while pursuing intensive pre-medical courses in chemistry. The results of the qualitative data analyses using a course experience questionnaire indicated that the process-oriented guided inquiry learning (POGIL) experience helped the students succeed in rigorous pre-medical chemistry courses and gained some process skills required in the medical programme as listed by the AAMC (American Association of Medical Colleges).

© American Society for Engineering Education, 2018. Today, learning in the engineering laboratory takes place via face-to-face and distance modes, the latter via the internet. Learning of laboratory skills in any mode of laboratory is influenced by the interactions that occur between the students, instructors and the equipment in the laboratory. Recent innovations have focused on developing new remotely controlled laboratories for various disciplines in engineering studies. These laboratories focus purely on technical aspects and may struggle to provide an environment for the development of personal and professional skills that are also a critical part of an engineering student's education. In this research, quantitative and qualitative surveys were conducted at two Australian institutions to measure first-year students' interactions and capturing their experience in these two contrasting laboratory modes. Quantitative survey data showed that students were more satisfied and valued social interactions more in the remotely controlled laboratory than in the face-to-face laboratory. By contrast qualitative responses revealed that their first preference was still face-to-face laboratories because they valued the importance of gaining hands-on experience of the experiment, working in teams and under an instructor's guidance as an engineering student. Students also preferred remote laboratory work to be introduced at a later stage in their engineering studies when they are conceptually more capable and experienced.

© 2018, Springer Science+Business Media B.V., part of Springer Nature. Three novel C4symmetric O-substituted derivatives of tetramethoxyresorcinarene were synthesised and characterised and the selective distal lithiation of these derivatives was investigated. Lithiation of the tetraethoxy derivative, followed by quenching with dimethyldisulfide selectively afforded the distal product in 36% yield after removal of unreacted starting resorcinarene. Lithiation of the MOM derivative produced the five possible lithiated products, with the mono being the major product; the distally substituted derivative being a minor product. The benzyloxyresorcinarene appeared to be unstable under the lithation conditions. These results suggest that the selectivity of the distal lithation reaction is heavily dependent on the O-substituents of the resorcinarene.

© 2018 Springer Science+Business Media B.V., part of Springer Nature Educational reforms in Qatar have seen the implementation of inquiry-based learning and other student-centred pedagogies. However, there have been few efforts to investigate how these adopted western pedagogies are aligned with the high context culture of Qatar. The study presented in this article highlights the implementation of a student-centred intervention called Process-Oriented Guided Inquiry Learning (POGIL) in selected independent Arabic government schools in Qatar. The study followed a theoretical framework composed of culturally relevant pedagogical practice and social constructivism in teaching and learning. A mixed method research design involving experimental and comparison groups was utilised. Carefully structured learning materials when implemented systematically in a POGIL intervention helped Grade 10 science students improve their perceptions of chemistry learning measured from pre- and post-tests as measured by the What Is Happening In this Class (WIHIC) questionnaire and school-administered achievement test. The study further provided school-based mentoring and professional development opportunities for teachers in the region. Significantly, POGIL was found to be adaptable in the Arabic context.

Lanthanoid picrate (pic) complexes of 5,11,17,23-tetra-tert-butyl-25-hydroxy-26,27,28-tris(diethylcarbamoylmethoxy)calix[4]arene (LH) have been synthesised and structurally characterised, to complete this series for all lanthanoids (other than promethium). From cerium to lutetium, three structural types are observed: Type I, [Ln(L)(O,O'-pic)](pic), Ln = Ce-Dy; Type II, [Ln(L)(O-pic)](pic), Ln = Tb, Ho; Type III, [Ln(L)(HOEt)](pic)2, Ln = Er-Lu. With lanthanum, three different ten-coordinate complexes were characterised; [Ln(L)(O,O'-pic)(HOEt)](pic), [Ln(L)(O,O'-pic)(OH2)](pic), and [Ln(L)(O,O'-pic)(HOMe)](pic). The crystallisation of Type I and II observed for terbium shows that the stability of the different structures are sensitively poised at the transition points. Nevertheless, the structures show that the vacant space in the coordination sphere left by the trisamide L tends to reduce across the series as expected. It is occupied by a bidentate picrate anion and unidentate solvent molecule with lanthanum, a bidentate picrate anion for cerium to dysprosium (Type I), a unidentate picrate anion for terbium and holmium (Type II), and finally a unidentate solvent molecule from erbium to lutetium (Type III). The coordination number thus reduces from 10 to 8 across the series.

© 2017 Author(s). One of the essential facets in teacher education program is the development of the teachers' content knowledge and it has been suggested by many scholars that the study to analyse the process of content knowledge development in teacher education program is necessary. Regarding this, the aim of this research is to evaluate the existing program of developing pre-service chemistry teachers' content knowledge, especially in the topic about the particulate nature of matter. The curriculum of content knowledge development was analysed using the forms of the curriculum evaluation (Akker, 1998; Goodlad, Klein, and Tye (1979); Treagust, 1987). Within this framework, the curriculum was evaluated in several aspects including the vision and intention of the curriculum as mentioned in the curriculum documents (intended curriculum), the users' interpretation and perception about the curriculum (perceived curriculum), the actual process of curriculum implementation (implemented curriculum), and the outcomes of the curriculum (achieved curriculum). According to the framework used for this study, the research combined qualitative and quantitative methods of data collection and the interpretation including document analysis, classroom observation, interviews, and two-tier diagnostic test. Through this research we examined the coherence among those aspects. The results reveal that although the content knowledge development is explicitly intended in a curriculum, its implementation and lecturers' perceptions give influence in the results as appear in pre-service teachers' achievements. In general, this research provides basic information about the effectiveness of the program including the challenges and the potentials for a reconsideration of the program in the future.

Assessment of students’ performance in laboratory activities evaluates students’ achievements and weaknesses in practical work. This is vital from both student and institutional perspectives. Pra ctical skills assessment methods evaluate students on three major components: the ability to collect data and perform calculations, to analyse the cause of failures in the process, and finally students’ active engagement and participation in the practical work. A conventional, report-based, assessment method combined with an alternative method, termed in-class assessment, were developed and used for second-year Fluid Mechanics laboratory work. In this article, we describe these two approaches and present the results of a quantitative investigation of students’ responses. Students expressed similar experience and satisfaction levels for each of the assessment methods that measured the attainment of different but essential personal and professional skills stipulated by the professional body for students graduating with an engineering degree. These skills include the development of research skills, conceptual understanding, application of techniques, preparing a report, team working abilities and the communication skills needed to interact with peers and demonstrators effectively. This article shows that the use of in-class assessment can serve as a useful complement to conventional report-based assessment methods ensuring optimal laboratory learning for students across engineering knowledge and skills areas.

A new tool has been developed to help elucidate the differences in packing between different polymorphs, especially when the differences of interest are small. The technique builds upon the Hirshfeld fingerprint plot pioneered by Spackman and co-workers by subtracting the value at every point in a fingerprint plot from the value at every point in another. This is found to reveal differences that are not readily apparent to the eye. By summing the absolute values of these differences, a quantitative measure of the difference between two fingerprint plots can be obtained. The technique was applied to Ni and Cu trans-bis(2-hydroxy-5-methylphenonethanoneoximato) complexes determined at two temperatures, with the Ni complex displaying temperature-dependent polymorphism. Difference Hirshfeld fingerprint plots were also generated for calculated structures from DFT simulations that were performed on the experimental structures. These demonstrated that the simulations reproduced the fine detail of the packing.

The importance of observation in science and science education has triggered this laboratory development study that investigated the value of an observation kit as a new approach to teaching rate of reaction in general chemistry class. The kit consists of a digital microscope, a “chemical reactor”, and a tailor-made computer application and was used to video-record a solid-liquid reaction and to produce a series of two dimensional solid images that indicate the extent of reaction. The two dimensional image areas were calculated by the computer application by assuming that the image area was directly proportional to the solid mass from which a plot of mass versus time could be obtained. These steps have been tested to solid (zinc, iron, calcium carbonate, and magnesium oxide)-liquid (acid solution reaction systems. Reaction of solid magnesium oxide with nitric acid solution resulted in the best images which were transferable to a plot of solid magnesium oxide mass as a function of time. This was used to explain rate of reaction concepts including average, instantaneous, and initial rate. Furthermore, the effect of concentration on reaction rate could also be explained. The generated data allows students to clearly and repeatedly visualize a solid-liquid reaction and relates rates of reaction concepts. The observation kit also allows teachers and students to extend its application into inquiry based experiments. © 2017, Gadjah Mada University. All rights reserved.

Condensation of phenylephrine with different aldehydes, under Pictet-Spengler cyclisation conditions, afforded a series of tetrahydroisoquinoline derivatives as mixtures of cis/trans isomers. Single crystal X-ray analysis of the dibenzoate derivative of one of the 4-nitrophenyl isomers confirmed it to be the trans isomer. The conformation of the cis isomer was determined through computational experiments and comparison of the predicted and observed 1H NMR spectra, particularly the magnitude of the coupling constants. Fourteen tetrahydroisoquinoline derivatives were then evaluated for their activity towards T. b. rhodesiense, two strains of P. falciparum, and mammalian cells. The most promising derivative, the undecyl derivative, showed good activity towards T. b. rhodesiense with an IC50 value in the sub-micromolar range and good selectivity over mammalian cells. The same derivative also showed activity against both strains of P. falciparum with IC50 values in the low micromolar range.

Human African Trypanosomiasis (HAT), a neglected disease endemic in Sub-Saharan Africa, is usually fatal if left untreated. It is caused by the parasite Trypanosoma brucei, and is spread by the tsetse fly. The drugs currently available to treat HAT are few, and limited in efficacy. Furthermore, resistance towards these drugs is beginning to grow. In the last 25 years only one advance has been made into HAT treatment and consequently, there is an increasing need for new drugs to be sought that are able to effectively treat this disease. This review provides a brief overview of drug discovery research for HAT, focusing on research published in the last four years, identifying new molecules with the potential to be developed into anti-HAT agents. The methods of drug discovery have been grouped into three key areas; new molecules inspired by known antitrypanosomal agents, target-based screening, and phenotypic screening.

The thermal annealing behaviour of an electrolyte-triggered calixarene hydrogelator is found to depend strongly on the specific metal chloride used. While the lithium chloride gel showed typical gel-sol transitions as a function of temperature, the magnesium chloride gel was found to repeatedly strengthen with heat-cool cycles. Structural investigations using small-angle neutron scattering, and scanning probe microscopy, suggest that the annealing behaviour is associated with a change in morphology of the fibrous structures supporting the gel. On prolonged standing at room temperature, the magnesium chloride gel underwent a gel-crystal transition, with the collapsing gel accompanied by the deposition of crystals of a magnesium complex of the proline-functionalised calix[4]arene gelator.

Pedagogical practitioners who emphasise active learning in undergraduate chemistry courses widely use the Student Assessment of Learning Gains (SALG) instrument to measure students' perceptions of their gains in knowledge and skills in chemistry. Although numerous studies have reported SALG results in support of successful pedagogical interventions, a comprehensive construct-verified version measuring students' perceptions of their chemistry learning is lacking. This paper aims to identify latent constructs of the SALG instrument that was administered in Process Oriented Guided Inquiry Learning (POGIL) classes by using exploratory and confirmatory factor analyses. When the SALG was administered on two separate occasions with two different groups of students following four weeks of instruction on topics in stereochemistry, the results revealed a four-factor structure consisting of 32 items that included Active Learning, Concept Learning, Resources, and Process Skills. These findings demonstrate an approach to collect evidence to support the match between intended constructs and measured variables in light of a targeted pedagogical intervention.