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Target lipid model (TLM) and toxic unit (TU) approaches were applied to ecotoxicity and chemistry data from low-energy WAFs (LE-WAFs) of source and weathered crude oils originating from the Deepwater Horizon oil spill. The weathered oils included artificially weathered oils and naturally weathered samples collected in the Gulf of Mexico after the spill. Oil weathering greatly reduced the concentrations of identified LE-WAF components, however, the mass of uncharacterized polar material (UPC) in the LE-WAFs remained largely unchanged during the weathering process. While the TLM-derived calculations displayed a significant decrease in toxicity (TUs) for the heavily weathered oils, copepod toxicity, expressed as LC10-based TUs, were comparable between LE-WAFs of fresh and weathered oils. The discrepancy between observed and predicted toxicity for the LE-WAFs of artificially weathered oils may be related to limitations by the chemical analyses or increased toxicity due to generation of new unknown compounds during the weathering process. [ABSTRACT FROM AUTHOR]

Background: Corrosion at the head-neck junction of femoral stems is a rare complication of total hip arthroplasty (THA) with manifestations ranging from subclinical wear to failure. Prior studies have identified a single femoral component design with an increased propensity for catastrophic trunnion failure. The purpose of the present study was to quantify trunnion damage of this femoral component retrieved from patients undergoing revision THA for non-trunnionosis indications. Methods: 24 femoral components from a single manufacturer were identified for study inclusion. Each prosthesis underwent stereomicroscopic inspection. Corrosion and fretting scores were assigned per the Goldberg criteria to quadrants of the trunnion. Material loss was calculated based on cone angles across trunnion quadrants. This was carried out using a coordinate measuring machine that digitised each trunnion surface. Stems were compared to a series of femoral stems with the same trunnion design. Results: 20 of the 24 (83%) trunnions demonstrated corrosion, all 24 trunnions demonstrated fretting. Corrosion scores did not statistically differ with respect to trunnion zone (p = 0.53), while fretting scores were higher in the inferior compared to the superior zones (p < 0.001). There was no significant difference in cone angles assessing material loss between stems (p = 0.25). Conclusions: Evidence of trunnion damage was observed in each stem retrieved for non-trunnionosis revision. Fretting occurred more frequently about the inferior quadrants. However, digitised trunnion shapes were similar between compared stems exhibiting no material loss. Therefore, it is possible that previous reports of trunnion failures for this implant are not a systemic issue, and that further investigation is required. [ABSTRACT FROM AUTHOR]

In this work, two-dimensional n -dodecane/air/nitrogen cellular detonations are simulated with various equivalence ratios (ERs). A skeletal mechanism consisting of 54 species and 269 reactions is used. The lower and upper equivalence ratio boundaries for self-sustained detonation are 0.3 and 2.2, respectively. Detonation with different regimes characterized by the detonation cell patterns is observed, which aligns well with the category based on the stability parameter, i.e., weakly and highly unstable detonations, and extinction. In terms of the frontal structure, non-negligible effect of diffusion on the cellular detonation is revealed, especially in the vicinity of the leading shock front. In highly unstable and quenched detonations, the alternation in reaction pathway within the induction zone accounts for the changes of detonation dynamics, such as the absence or extended sequence of important radical formation, e.g., OH. In addition, the composition of the unburned pockets depends on both pocket location from the leading shock front and the ER in the fresh mixture, because the former determines the residence time, whilst the latter affects the pocket reaction rate. • The significance of detonation front on the chemistry explosive mode are revealed through CEMA. • Cellular structure and detonation dynamics in mixtures with various ERs are investigated. • The reaction pathways at various locations behind the leading shock front are compared. [ABSTRACT FROM AUTHOR]

Summary Gelatine is obtained from the hydrolysis of collagen in bones, skin, fins, fish scales and insect bodies of cattle, pigs, camels, poultry, fish and insects. Consequently, the diversity and availability of gelatine sources, along with gelatine authentication, are concerns for those consuming gelatine products from religious, health and economic perspectives. Therefore, rapid and reliable protein‐ or DNA‐based detection methods have been developed for gelatine authentication. This review discusses and evaluates biosensor methods, comparing them with various analytical methods in terms of their popularity and precision. Additionally, the development of biosensor methods has been explored to identify a reference for a rapid, accurate, portable and simple method for gelatine detection with a low detection limit and high specificity. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive structural analysis of the adducts formed upon the reaction of two Ru(III) complexes [HIsq][trans-RuIIICl4(dmso)(Isq)] (1) and [H2Ind][trans-RuIIICl4(dmso)(HInd)] (2) (where HInd-indazole, Isq-isoquinoline, analogs of NAMI-A) and two Ru(II) complexes, cis-[RuCl2(dmso)4] (c) and trans-[RuCl2(dmso)4] (t), with hen-egg white lysozyme (HEWL). Additionally, the crystal structure of an adduct of human lysozyme (HL) with ruthenium complex, [H2Ind][trans-RuCl4(dmso)(HInd)] was solved. X-ray crystallographic data analysis revealed that all studied Ru complexes, regardless of coordination surroundings and metal center charge, coordinate to the same amino acids (His15, Arg14, and Asp101) of HEWL, losing most of their original ligands. In the case of the 2-HL adduct, two distinct metalation sites: (i) Arg107, Arg113 and (ii) Gln127, Gln129, were identified. Crystallographic data were supported by studies of the interaction of 1 and 2 with HEWL in an aqueous solution. Hydrolytic stability studies revealed that both complexes 1 and 2 liberate the N-heterocyclic ligand under crystallization-like conditions (pH 4.5) as well as under physiological pH conditions, and this process is not significantly affected by the presence of HEWL. A comparative examination of nine crystal structures of Ru complexes with lysozyme, obtained through soaking and co-crystallization experiments, together with in-solution studies of the interaction between 1 and 2 with HEWL, indicates that the hydrolytic release of the N-heterocyclic ligand is one of the critical factors in the interaction between Ru complexes and lysozyme. This understanding is crucial in shedding light on the tendency of Ru complexes to target diverse metalation sites during the formation and in the final forms of the adducts with proteins. [ABSTRACT FROM AUTHOR]

The alchemical concepts of chemical symbolism, nomenclature, and affinity underwent fundamental changes between the 1770s and the 1820s, roughly simultaneously with the Chemical Revolution (ca. 1772–89), i. e. the replacement of the phlogiston theory with Lavoisier's New Chemistry. Using the old, alchemical symbols, Bergman devised a system of formulas to describe virtually all known inorganic chemistry, and he influenced Guiton de Morveau's Mémoire sur les Dénominations Chimiques, and the subsequent Méthode de nomenclature. Hassenfratz and Adet devised a new artificial sign language which, however, was too complicated and unintuitive to gain widespread acceptance. Bergman refined the concept of affinity, but his belief in phlogiston rapidly made the system obsolete. Wenzel realized that the dissolution of metals in acids is not just a question of affinity but rather of concentration, and he and Berthollet separately formulated early versions of the Law of Mass Action thereby making attempts to quantify affinity redundant. Richter formulated a principle that became known as the Law of Equivalent Proportions, describing acid‐base reactions and double decompositions of salts, but continuing to use Bergman‐style alchemical formulas. Only John Dalton's atomic theory with little globules denoting atoms and their combination into molecules made a definite break with the alchemical symbols. [ABSTRACT FROM AUTHOR]

The extracurricular innovation laboratories serve vital expansion and valuable complement to the traditional teaching laboratory and play a crucial role in developing students' innovative abilities. Given the variety of experiments conducted, the open management of these laboratories presents significant challenges. This paper examines the issues faced by chemical extracurricular innovation laboratories which are opening to undergraduate students and explores corresponding management approaches involving the enhancement of institutional safeguards, the clarification of safety responsibilities, the optimization of resource allocation and opening up of new management models from managerial perspective. These efforts aim to provide robust support for the cultivation of innovative talents. [ABSTRACT FROM AUTHOR]

The way of thinking of mathematicians and chemists in their respective disciplines seems to have very different levels of abstractions. While the firsts are involved in the most abstract of all sciences, the seconds are engaged in a practical, mainly experimental discipline. Therefore, it is surprising that many luminaries of the mathematics universe have studied chemistry as their main subject. Others have started studying chemistry before swapping to mathematics or have declared some admiration and even love for this discipline. Here I reveal some of these mathematicians who were involved in chemistry from a biographical perspective. Then, I analyze what these remarkable mathematicians and statisticians could have learned while studying chemical subjects. I found analogies between code-breaking and molecular structure elucidation, inspiration for statistics in quantitative analytical chemistry, and on the role of topology in the study of some organic molecules. I also analyze some parallelisms between the way of thinking of organic chemists and mathematicians in terms of the use of backward analysis, search for patterns, and use of pictures in their respective researches. [ABSTRACT FROM AUTHOR]

It is widely recognized that conceptual and theoretical innovations and the employment of new instruments and experimental techniques are important factors in explaining the growth of scientific knowledge in chemistry. This study examines another dimension of research in chemistry, collaboration and co-authorship. I focus specifically on Theodore Richards' career and publications. During the period in which Richards worked, co-authorship was beginning to become more common than it had been previously. Richards was the first American chemist to be awarded a Nobel Prize and he was at the forefront in this new trend in chemistry. He collaborated more than was typical for his time, with many scientists, in different sized groups, and he often had persistent collaborative relationships, extending over a number of years. Further, it appears that these collaborations benefited Richards, his collaborators, and the field of chemistry as a whole. [ABSTRACT FROM AUTHOR]

Organisms in nature have evolved a variety of surfaces with different tribological properties to adapt to the environment. By studying, understanding, and summarizing the friction and lubrication regulation phenomena of typical surfaces in nature, researchers have proposed various biomimetic friction regulation theories and methods to guide the development of new lubrication materials and lubrication systems. The design strategies for biomimetic friction/lubrication materials and systems mainly include the chemistry, surface structure, and mechanics. With the deepening understanding of the mechanism of biomimetic lubrication and the increasing application requirements, the design strategy of multi-strategy coupling has gradually become the center of attention for researchers. This paper focuses on the interfacial chemistry, surface structure, and surface mechanics of a single regulatory strategy and multi-strategy coupling approach. Based on the common biological friction regulation mechanism in nature, this paper reviews the research progress on biomimetic friction/lubrication materials in recent years, discusses and analyzes the single and coupled design strategies as well as their advantages and disadvantages, and describes the design concepts, working mechanisms, application prospects, and current problems of such materials. Finally, the development direction of biomimetic friction lubrication materials is prospected. [ABSTRACT FROM AUTHOR]

Legionella pneumophila, the leading cause of Legionnaires' disease in the United States, is found in lakes, ponds, and streams but poses a health risk when it grows in building water systems. The growth of L. pneumophila in hot water systems of healthcare facilities poses a significant risk to patients, staff, and visitors. Hospitals and long-term care facilities account for 76% of reported Legionnaires' disease cases with mortality rates of 25%. Controlling L. pneumophila growth in hot water systems serving healthcare and hospitality buildings is currently achieved primarily by adding oxidizing chemical disinfectants. Chemical oxidants generate disinfection byproducts and can accelerate corrosion of premise plumbing materials and equipment. Alternative control methods that do not generate hazardous disinfection byproducts or accelerate corrosion are needed. L. pneumophila is an obligate aerobe that cannot sustain cellular respiration, amplify, or remain culturable when dissolved oxygen (DO) concentrations are too low (< 0.3 mg/L). An alternative method of controlling L. pneumophila growth by reducing DO levels in a hot water model system using a gas transfer membrane contactor was evaluated. A hot water model system was constructed and inoculated with L. pneumophila at DO concentrations above 0.5 mg/L. Once the model system was colonized, DO levels were incrementally reduced. Water samples were collected each week to evaluate the effect of reducing dissolved oxygen levels when all other conditions favored Legionella amplification. At DO concentrations below 0.3 mg/L, L. pneumophila concentrations were reduced by 1-log over 7 days. Under conditions in the hot water model system, at favorable temperatures and with no residual chlorine disinfectant, L. pneumophila concentrations were reduced by 1-log, indicating growth inhibition by reducing DO levels as the sole control measure. In sections of the model system where DO levels were not lowered L. pneumophila continued to grow. Reducing dissolved oxygen levels in hot water systems of healthcare and other large buildings to control L. pneumophila could also lower the risk of supplemental chemical treatment methods currently in use. [ABSTRACT FROM AUTHOR]

Background: Haptic feedback has been shown to be an effective facilitator of the learning of scientific concepts in a series of studies. However, little is known about the underlying salient learning mechanisms, which are activated when learning from haptic feedback. Objectives: We investigate the learning mechanism in a higher chemistry education setting, in which the students learned about the abstract concept of potential energy in a quantum chemical context. Methods: In this work, we present a mixed‐methods problem‐solving prior to instruction (PS‐I) study with chemistry bachelor students. In an interactive quantum chemistry learning environment, the students explored the energetic profiles of nucleophilic substitution reactions and the corresponding activation barriers experienced as repulsion and attraction. We measured cognitive and affective mechanisms which have been shown to be activated in PS‐I designs, such as knowledge gap awareness, state curiosity, and positive affect as well as the learning outcome quantitatively and the learning trajectories qualitatively. Results and Conclusions: Planned contrasts revealed a small hindering effect of the haptic feedback on the learning outcome. Thematic analysis of the qualitative data lets us attribute this effect to the lack of scaffolding of the haptic feedback and the spontaneous atomic movements in the simulation, which may be interpreted as a visual representation of force in itself. This work highlights the importance of accurate mappings of the haptic feedback unto the target domain and further delivers insight into the prior conceptions of chemistry undergraduate students. Lay Description: What is already known about this topic: Haptic feedback can facilitate learning by grounding abstract concepts in sensory experiences.While previous studies have reported positive affective results, the cognitive results are ambiguous.Moreover, it was frequently reported that the learning of potential energy in a (quantum) chemical context is particularly difficult due to (i) the lack of grounding opportunities and (ii) the diverse previous conceptions. What this paper adds: A learning environment to interact with molecular systems in real‐time is proposed.The concept of activation energy is grounded in sensory experience of pushing and being pulled.The mixed‐methods design allows to explore cognitive and affective variables as well as the specific prior conceptions activated by the environment. Implications for practice and/or policy: We found a small negative effect of the haptic feedback on the learning outcome, potentially due to insufficient introduction of it to the students.The spontaneous movement of the atoms was identified as a more suitable external representation of the force.Future studies should investigate, if explicit introduction of the embodied metaphor can reverse this effect. [ABSTRACT FROM AUTHOR]

With air traffic expected to grow 5% annually until the year 2030, alternative fuels such as hydrogen are being investigated in order to tackle the current environmental crisis. Due to safety concerns, future hydrogen combustion chambers will require new designs of injection systems and are expected to operate under multimode combustion regimes. From a large-eddy-simulation (LES) perspective, a prerequisite for the shift toward new hydrogen combustion chamber technologies is a robust turbulent combustion model capable of functioning in non-premixed conditions. Turbulent combustion modeling using flame front filtering is a well-developed strategy in premixed combustion (filtered-tabulated chemistry for large-Eddy-simulation (F-TACLES)). This approach has been extended to non-premixed flames however, it suffers from high flame filter size sensitivity. Moreover, thin hydrogen flame fronts will result in lower resolution on the LES grid, potentially amplifying this issue. In order to address the feasibility of the non-premixed F-TACLES model applied to hydrogen fuel, simple one-dimensional and two-dimensional laminar counterflow diffusion flames are computed. The model is then tested on the three-dimensional Sandia hydrogen jet flame with a Reynolds number of 10,000. Simulations and a priori tests show that tabulated subgrid-scale correction terms are stiff and can result in nonphysical results, however the model is capable of correctly reproducing non-premixed flame structures for small filter sizes. [ABSTRACT FROM AUTHOR]

Cannabis sativa is one of the oldest plants utilized by humans for both economic and medical purposes. Although the use of cannabis started millennia ago in the Eastern hemisphere, its use has moved and flourished in the Western nations in more recent centuries. C. sativa is the source of psychoactive cannabinoids that are consumed as recreational drugs worldwide. The C21 aromatic hydrocarbons are restricted in their natural occurrence to cannabis (with a few exceptions). Delta-9-tetrahydrocannabinol (Δ9-THC) is the main psychoactive component in cannabis, with many pharmacological effects and various approved medical applications. However, a wide range of side effects are associated with the use of Δ9-THC, limiting its medical use. In 1966, another psychoactive cannabinoid, Delta-8-tetrahydrocannabinol (Δ8-THC) was isolated from marijuana grown in Maryland but in very low yield. Δ8-THC is gaining increased popularity due to its better stability and easier synthetic manufacturing procedures compared to Δ9-THC. The passing of the U.S. Farm Bill in 2018 led to an increase in the sale of Δ8-THC in the United States. The marketed products contain Δ8-THC from synthetic sources. In this review, methods of extraction, purification, and structure elucidation of Δ8-THC will be presented. The issue of whether Δ8-THC is a natural compound or an artifact will be discussed, and the different strategies for its chemical synthesis will be presented. Δ8-THC of synthetic origin is expected to contain some impurities due to residual amounts of starting materials and reagents, as well as side products of the reactions. The various methods of analysis and detection of impurities present in the marketed products will be discussed. The pharmacological effects of Δ8-THC, including its interaction with CB1 and CB2 cannabinoid receptors in comparison with Δ9-THC, will be reviewed. [ABSTRACT FROM AUTHOR]

Those who work with wood should have a basic knowledge of wood anatomy and chemistry so they can understand how different anatomical and chemical features influence wood properties and, in turn, how these properties contribute to different treatments and final wood utilization. However, little attempt has been made to map global research trends in wood anatomy and chemistry. This paper presents a bibliometric review of research trends in wood anatomy and chemistry to determine research trends and gaps in these research areas. A total of 183 publications on wood anatomy and chemistry from 1974 to 2023 were reviewed. The analysis was done with the VOSviewer software (version 1.6.13). The analysis focused on the bibliographic coupling of countries, co-authorship of authors, citation of documents, and co-occurrence of keywords, which were presented as network visualization maps. The findings revealed that the wood anatomy and chemistry publication trends, although not completely gradient, have been upwards since 2000. Countries including Germany, the United States, Switzerland, the United Kingdom, Brazil, the Netherlands, China, Italy, Mexico, Spain, the Czech Republic, Canada, Australia, Chile, Finland, France, Sweden, and Japan had a great impact on this research area. It also became evident that African countries lag in this area of research. Only one data source - Scopus - was used. It has a wide coverage of publications from diverse areas and provides researchers with information on the most important academic literature in any specific scientific domain. Therefore, the representation of publications presented in this study is limited to only the Scopus data source. [ABSTRACT FROM AUTHOR]

Marie Curie Lab STEAM Room is an immersive interactive didactic activity with an educational approach STEAM (Science, Technology, Engineering, Art, and Mathematics), which integrates these disciplines and uses active teaching methodologies, in this case an educational escape room, for the achievement of significant learning. The objective of the activity is to bring the participants closer to science in a playful way, working on curricular contents of the STEAM disciplines in a context of interest to students, which promotes the development of skills for the 21st century. The escape room was presented in the first semester of 2022, at the Institute of Engineering to the university community. Four presentations were made, each with four teams of approximately three members, who worked collaboratively to overcome the challenges posed. The result of the presentation shows that the participants favorably evaluated the activity, found it creative, fun, and stated that they had learned about chemistry, teamwork and about Marie Curie as a scientific figure of reference. The implementation of this activity shows that educational escape rooms are attractive immersion experiences for the participants. In addition to that they can be designed aligned to the curriculum of various subjects, for implementation in the classroom. They develop skills such as collaboration, critical thinking, and creativity; these experiences are demanding, challenging, interesting and fun at the same time. At the end of this investigation it was identified that there is an area of teacher training opportunity in relation to integrating this type of methodologies in teaching practice. [ABSTRACT FROM AUTHOR]

Countries are always looking for different ways to improve student achievement and reform education. Therefore, evaluation is considered the main component of all education systems. It can be used in schools to monitor education systems, and it also helps improve curricula. This study came with the aim of evaluating the unit of halogens and listing the characteristics of the group in chemistry from the point of view of the teachers’ view was based on the STICK model, and the descriptive analytical approach was relied upon through the questionnaire that was distributed to teachers from various governorates of the Sultanate, where the study sample was (120). After collecting the data, it was analyzed using the SPSS data package program, and a set of results were reached, the most important of which is Most teachers prepare presentation tools and an interactive whiteboard before starting classes, and they have the ability to ask brainstorming questions before starting to implement classes. This is due to the teachers’ experience, as the number of those included in the sample constitutes approximately 66%, which is more than half, and the unit topics are appropriate. 4 With the number of classes allocated to it, most teachers use modern technology in teaching the topics of this unit, and this statement is consistent with the first statement, the field of precedents, and they provide a final evaluation after completing teaching the topics of the unit. The results also indicated that there are no statistically significant differences at the level of significance (α =0.05) between the arithmetic averages of the evaluative scores for the topics of the halogen's unit and the gradation of group characteristics, which is in favor of males, while there were no statistically significant differences at the level of significance (α = 0.05) between the arithmetic averages of the evaluative scores for the topics of the halogen's unit and the gradation of group characteristics from the point of view of the teachers. According to the STICK model, it is attributed to the variable number of years of experience. [ABSTRACT FROM AUTHOR]

Pedagogical approaches for supporting students' argumentative writing in science laboratories have not been fully established. This article examines the development of argumentative abilities in undergraduate students enrolled in chemistry laboratory courses that employed two teaching sequences: (i) an argumentative writing workshop for conceptual learning and (ii) weekly laboratory report writing for application of knowledge gained in the workshop. The four workshop modules guided students through the process of identifying three key components of arguments (evidence, justifications, and claims), selecting appropriate and inappropriate justifications, constructing justifications and conclusions, and analyzing experimental errors. Student performance in formulating scientific arguments was evaluated through instructors' assessment of evidence, justifications, and claims made in the Results, Discussion, and Conclusions sections, respectively, of a laboratory report. Student performance improved from 60.9 ± 3.4 to 91.5 ± 8.0 in Introductory Chemistry I Lab and 60.7 ± 5.2 to 91.7 ± 5.4 in Introductory Chemistry II Lab. Students rated the helpfulness of the writing workshop ([3.6 ± 0.1]/5.0), weekly writing ([4.1 ± 0.3]/5.0), and instructors' feedback ([4.4 ± 0.5]/5.0) for both introductory and advanced chemistry laboratories positively. The format of this writing workshop can be used for online teaching or incorporated into any science laboratory course with the development of appropriate content modules. [ABSTRACT FROM AUTHOR]

Nonlinear curve fitting is an important process in laboratory medicine, particularly with the increased use of highly sensitive antibody-based assays. Although the process is often automated in commercially available software, it is important that clinical scientists and physicians recognize the limitations of the various approaches used and are able to select the most appropriate model. This article summarizes the key nonlinear functions and demonstrates their application to common laboratory data. Following this, a basic overview of the statistical comparison of models is presented and then a discussion of important algorithms used in nonlinear curve fitting. An accompanying Microsoft Excel workbook is available that can be used to explore the content of this article. [ABSTRACT FROM AUTHOR]

Iron oxide-copper–gold (IOCG) deposit genesis is often genetically linked to magmatism due to temporal association between granite and mineralization and participation of magma-derived components. In the Carajás Mineral Province, NW Brazil, a set of ca. 2.6–2.5 Ga IOCG deposits has been interpreted to be genetically linked to contemporary granite, which are located along the Cinzento Shear Zone, in the northern part of the province. Despite the apparent temporal correlation, the understanding of ca. 2.5 Ga ages as magmatic may be misleading, since ca. 2.6–2.5 Ga reset ages have been previously reported for deformed and hydrothermally altered granites crystallized at ca. 2.74 Ga. We studied the morphology, texture, and composition of 2.74–2.73 Ga, 2.68 Ga, 2.64–2.62 Ga, and 2.59–2.55 Ga zircons from variably deformed and metasomatized granites located along the Cinzento Shear Zone. Our study reveals re-equilibrated magmatic, deformed, and newly grown zircon domains with compositional changes (Ta, U, Y, and LREE enrichment relative to chondrite) that inconsistently follow textural patterns. The overprint arises from diffusion–reaction, coupled-dissolution-reprecipitation processes, and alteration of metamict zircons, likely aided by alkaline (Na–K-rich) and F-Cl-rich hydrothermal fluids that circulated regionally in the Carajás Province. Such processes account for disturbances and resetting of the U-Th-Pb isotopic system in zircon; therefore, the geochronological record in granites from our study can be associated with the first (ca. 2.72–2.68 Ga) and the second (ca. 2.6–2.5 Ga) IOCG-forming hydrothermal events rather than to igneous crystallization. In this context, we rule out a temporal link between granitic magmatism and the IOCG deposits at Carajás. [ABSTRACT FROM AUTHOR]

This work highlights the relevant contribution of conformational stereoisomers to the complexity and functions of any molecular compound. Conformers have the same molecular and structural formulas but different orientations of the atoms in the three-dimensional space. Moving from one conformer to another is possible without breaking covalent bonds. The interconversion is usually feasible through the thermal energy available in ordinary conditions. The behavior of most biopolymers, such as enzymes, antibodies, RNA, and DNA, is understandable if we consider that each exists as an ensemble of conformers. Each conformational collection confers multi-functionality and adaptability to the single biopolymers. The conformational distribution of any biopolymer has the features of a fuzzy set. Hence, every compound that exists as an ensemble of conformers allows the molecular implementation of a fuzzy set. Since proteins, DNA, and RNA work as fuzzy sets, it is fair to say that life's logic is fuzzy. The power of processing fuzzy logic makes living beings capable of swift decisions in environments dominated by uncertainty and vagueness. These performances can be implemented in chemical robots, which are confined molecular assemblies mimicking unicellular organisms: they are supposed to help humans "colonise" the molecular world to defeat diseases in living beings and fight pollution in the environment. [ABSTRACT FROM AUTHOR]

Internationally there is a shortage of psychiatrists, whilst clinical psychology training is generally oversubscribed. School students interested in psychological health may not be aware of the possibility of studying medicine before specialising in psychiatry. This has implications for the mental health workforce. To evaluate the knowledge and attitudes relating to a potential career in psychiatry amongst secondary (high) school students. A cross-sectional survey evaluated attitudes and knowledge relating to psychiatry and clinical psychology, targeting students from five schools who were studying chemistry, biology and/or psychology at an advanced level. 186 students completed the survey (response rate 41%). Knowledge was generally poor with only 57% of respondents knowing that psychiatrists had medical degrees, and most participants substantially underestimating the salaries of consultant psychiatrists. Attitudinal response patterns were explained by two underlying factors, relating to generally negative attitudes towards psychiatry and positive attitudes towards the effectiveness of psychiatric treatments. Females and those studying psychology reported more positive attitudes towards psychiatry. Those studying chemistry reported more negative attitudes towards the effectiveness of mental health treatment. Studying psychology predicted positive attitudes towards psychiatry. Such students could be targeted by recruitment campaigns, which emphasise factual information about the specialty. [ABSTRACT FROM AUTHOR]

In this special issue, we highlight recent advances in chemical research by scientists in Ukraine, as well as by their compatriots and collaborators outside the country. Besides spotlighting their contributions, we see our task in fostering global partnerships and multi‐, inter‐, and trans‐disciplinary collaborations, including much‐needed co‐funded projects and initiatives. The three decades of the renewed Ukraine independence have seen rather limited integration of Ukrainian (chemical) science into global research communities.[1] At the same time, the recent surge of collaborative science initiatives between European Union (EU) and Ukraine echoes the unfolding steps towards Ukraine's full research participation to the Horizon Europe Program. This recently implemented step opens enormous possibilities for Ukrainian researchers to apply for diverse EU research grants. Moreover, a number of journal special issues and collections were launched to highlight Ukrainian chemistry (i. e., by Chemistry of Heterocyclic Compounds[2] and ChemistrySelect[3]). Other scientific initiatives include 'European Chemistry School for Ukrainians'[4] and 'Kharkiv Chemical Seminar'[5] as voluntary projects aimed at engaging Ukrainian scientists into European and international chemical research. [ABSTRACT FROM AUTHOR]

With an increasing world population of nearly eight billion which is expected to expand towards nine billion by 2050, future food demands will rise unavoidably. Primary productivity of crop is at the center of the food and feed value chain. Excessive and low efficiency fertilization cause severe environmental and ecological problems, along with economic wastage. Next to fertilizers, also pesticides, plant growth regulators and other agrochemicals (e.g., stored animal manure and hormones) pose environmental issues and require specific technologies to ensure security of human health and the global ecosystem while increasing food productions. There is an agronomic, legal and environmental 'demand' to develop controlled release solutions to optimize agricultural practices. In this regard, (polymer) chemistry can offer a wide range of strategies to cope with the current issues related to biodegradation, overfertilization, pesticide use, efficient precision agriculture etc. through tailored material design allowing controlled active components release. Therefore, this review focusses on (polymer) chemical strategies to design controlled release systems in the agricultural industry, covering specifically the state-of-the-art from the past four years. [ABSTRACT FROM AUTHOR]

Background: Thiadiazines are heterocyclic compounds that contain two nitrogen atoms and one sulfur atom in their structure. These synthetic molecules have several relevant pharmacological activities, such as antifungal, antibacterial, and antiparasitic. Objectives: The present study aimed to evaluate the possible in vitro and in silico interactions of compounds derived from thiadiazines. Methods: The compounds were initially synthesized, purified, and confirmed through HPLC methodology. Multi‐drug resistant bacterial strains of Staphylococcus aureus 10 and Pseudomonas aeruginosa 24 were used to evaluate the direct and modifying antibiotic activity of thiadiazine derivatives. ADMET assays (absorption, distribution, metabolism, excretion, and toxicity) were conducted, which evaluated the influence of the compounds against thousands of macromolecules considered as bioactive targets. Results: There were modifications in the chemical synthesis in carbon 4 or 3 in one of the aromatic rings of the structure where different ions were added, ensuring a variability of products. It was possible to observe results that indicate the possibility of these compounds acting through the cyclooxygenase 2 mechanism, which, in addition to being involved in inflammatory responses, also acts by helping sodium reabsorption. The amine group present in thiadiazine analogs confers hydrophilic characteristics to the substances, but this primary characteristic has been altered due to alterations and insertions of other ligands. The characteristics of the analogs generally allow easy intestinal absorption, reduce possible hepatic toxic effects, and enable possible neurological and anti‐inflammatory action. The antibacterial activity tests showed a slight direct action, mainly of the IJ23 analog. Some compounds were able to modify the action of the antibiotics gentamicin and norfloxacin against multi‐drug resistant strains, indicating a possible synergistic action. Conclusions: Among all the results obtained in the study, the relevance of thiadiazine analogs as possible coadjuvant drugs in the antibacterial, anti‐inflammatory, and neurological action with low toxicity is clear. Need for further studies to verify these effects in living organisms is not ruled out. [ABSTRACT FROM AUTHOR]

The article is structured around the objective of understanding Mathematics and Chemistry embedded into integration curriculum materials in the Natural Sciences area, assessed and approved within the scope of the PNLD 2021. For this documentary research, we selected the teacher's handbook from a material defined as an integration project. After reading the introductory part of the presentation texts and guidance for developing two projects using such material, the analysis was guided by discussions of curriculum integration, work with projects, the analysis was guided by discussions of curriculum integration, work with projects and the knowledge of curriculum embedded Mathematics and Chemistry (KCEMC). The results indicate that the introductory part and the development of both projects lack transparency in conceptualizing curriculum integration, working with projects, and organizing content, which can restrict professional teaching knowledge and imply teaching practices that can diverge from the purposes of the curriculum material. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses articles in the issue on topics including "Alternative practical model for identifying primary numbers", and "Knowledge of mathematics and chemistry incorporated into integrative curricular materials".

Teaching and learning chemistry at all levels of education have faced numerous challenges. These challenges include students' struggles with problem-solving skills, limited spatial visualization abilities, difficulties in grasping chemistry vocabulary, and inadequate communication between students and teachers. As a result, researchers across various educational contexts have consistently advocated for the creation of a learning methods that effectively addresses these difficulties. This research delves into an examination of the pedagogical approaches, both as currently perceived and preferred, among PERMATA@Pintar College students in the realm of chemistry education. The investigation concentrates on two primary pedagogical paradigms: student-centered teaching and teacher-centered teaching. The study encompasses a cohort of 150 students ranging in age from 13 to 18 years. To gauge the students' perceptions of their teachers' instructional methods and their own preferences, a revised version of the Approaches to Teaching Inventory (ATI) originally developed by Prosser and Trigwell was employed. The findings of this study reveal that the prevailing pedagogical approach in chemistry classes appears to strike a balance between teacher-centered and student-centered learning. However, in terms of the students' own inclinations, they exhibit a slight preference for the teacher-centered method, emphasizing information transfer, over the student-centered approach, which emphasizes conceptual change. Interestingly, when considering the desired shift in teaching methods as envisioned by the students, their preference leans significantly towards an increased frequency of student-centered methods, highlighting a distinct preference for these methods over teacher-centered ones. [ABSTRACT FROM AUTHOR]

Too often, science courses (e.g., biology, chemistry, and physics) are disconnected from one another. When this happens, students often don't see how the different disciplines relate to one another. Through science and engineering practices (SEPs) and crosscutting concepts (CCCs), the NGSS has encouraged integration across disciplines. While much progress has been made in helping students make cross-disciplinary and interdisciplinary connections with SEPs and CCCs, disciplinary core ideas (DCIs) are still often siloed. One way to help students see connections between disciplines is to find DCIs that can be connected across courses. In this article, we demonstrate how we used a high school chemistry lesson on the concentration and temperature of reactions (HS-PS1-5) to make connections to the digestive system, cooking and baking, and cellular respiration (HS-LS1-7). [ABSTRACT FROM AUTHOR]

This article explores the levels of engagement that students experience during maker-centered instruction, with a particular focus on students in two secondary STEM classrooms. The authors first define key terms related to making and maker-centered instruction, emphasizing the importance of experiential learning and the maker mindset. The authors then describe the lesson context and discuss how engagement was perceived by students. The article draws on three views of engagement: engagement as a partnership with students, engagement as a multidimensional construct, and engagement as a continuum of student actions. The authors conclude with implications for promoting student investment in learning through explicit attention to engagement in lesson planning and implementation. The authors highlight the importance of maker education in supporting content knowledge and skill-building while also empowering students to invest in their learning. Ultimately, the article emphasizes the potential for maker-centered instruction to promote active and engaged learning for all students and highlights the need for the support of student engagement through explicit lesson design and student reflection. [ABSTRACT FROM AUTHOR]

The Solar Panel Modeling Project challenged 10th-grade chemistry students to apply knowledge of Atomic Models to explain electricity generation in a solar panel, deepening their scientific literacy about climate solutions. Here, I describe the project's implementation and outcomes, including the solar panel model template, the 9-day learning sequence, and the evolution of student thinking captured in the summarizing whole-class model. Throughout the unit, students alternated between investigating new chemistry concepts and iteratively refining models, exercising their NGSS sense-making skills. Content learning focused primarily on Atomic Models and the Octet Rule, but also included brief introductions to Lattice Stability and the Photoelectric Effect. The real-world context of the project showed students the practical utility of the otherwise esoteric skill of mapping electron locations and movements between elements. By the project's end, students could verbalize how the specific structure of Silicon, Boron, and Phosphorus in a solar panel results in electron movement and electricity. These students now face the upcoming decades of climate solutions debates armed with deeper scientific literacy about the readiness of this technology for widespread implementation. [ABSTRACT FROM AUTHOR]

Sir Rupert Horace Myers (1921–2019) was born in Melbourne and educated at Melbourne Boys High School and the University of Melbourne, where he was awarded a PhD degree in 1948 for research on the production of rare metals from Australian ores. As part of an Australian delegation, he worked at the Atomic Energy Research Establishment at Harwell in the United Kingdom on production of uranium and plutonium metals. He returned to Australia in 1952 as foundation professor of metallurgy at the still very young University of New South Wales, where he later became vice-chancellor, serving from 1969 to 1981 before entering a long and fruitful retirement. Knighted in 1981, he was a model of scientific and academic leadership in Australia. Metallurgist Rupert Horace Myers (1921–2019) was awarded Australia's first 'science' PhD degree in 1948. After working at the Atomic Energy Research Establishment at Harwell in the United Kingdom, he made his career at the University of New South Wales, where he was vice-chancellor from 1969 to 1981. Knighted in 1981, he was a model of scientific and academic leadership in Australia. Photograph provided by the Australian Academy of Science (photographer unknown). [ABSTRACT FROM AUTHOR]

In 1867, controversy erupted when Jean-Anne-Henri Depaul, a Paris accoucheur , tested Justus von Liebig's new "food for infants" on four newborns, all of whom died within days. This paper examines the origins of Liebig's food, the debates in the French Academy of Medicine after Depaul's experiment, and how the events were discussed in the medical and popular presses. I argue that the controversy was shaped by a number of interconnected concerns, including the product's impracticality, disagreements within the field of chemistry, the riskiness of Depaul's experimentation, Liebig's problematic celebrity, the potential hubris of trying to emulate a natural product, and national tensions between France and Germany. Infant feeding was an emotionally charged and highly politicized site where multiple interests, anxieties, and ways of knowing collided. Although commercial infant foods, many of which made reference to Liebig in their advertising, would ultimately find popularity in the last decades of the nineteenth century, close attention to the first years of Liebig's product demonstrates that its credibility as a "scientific" mode of infant feeding was far from assured. Rather, Liebig's milk illustrates the early challenges of constructing and enforcing knowledge and trust at the intersection between food, science, and infant life, in both professional and popular arenas. [ABSTRACT FROM AUTHOR]

As scholarly communication becomes more multimodal in nature, research articles embrace semiotic resources in appended genres such as the graphical abstract (GA). As an established genre in Chemistry research articles, GAs visually remediate chemical processes or research niche. However, this genre still remains in a peripheral area of English for Specific Purposes (ESP) courses as ESP practitioners mainly focus on textual modes. With limited opportunities to compose GAs, students foster genre remediation skills that are limited to textual genres only, ignoring the potential of reading-to-design skills. Upon student composition and critical reflections on GAs, as well as qualitative and quantitative data collection from a survey and interview involving professors, young researchers (YRs) and students, this paper examines rhetorical functions as well as image and text relations, while throwing some light on skills and challenges involved when GA composition is intentionally embedded in an ESP course, and discusses ensuing pedagogical implications. • Switching from reading-to-write to reading-to-design skills. • Embedding critical visual literacy tasks and student remediation of RAs. • Visual remediation awareness through student agency and reflection. [ABSTRACT FROM AUTHOR]

This study explores the changes in perceptions of transitional challenges faced by learners studying Chemistry through English-medium instruction (EMI) at a university in Japan over one academic semester. The research investigates the relationship between students' English proficiency, academic performance, and their perception of transitional challenges. The study involves 27 students from an introductory Chemistry course and adopts a mixed-methods approach. The quantitative analysis utilises IELTS scores, as well as pre-and post-content tests, to examine the relationship between language proficiency and academic performance. Complementing these findings, the qualitative analysis provides insights from semi-structured interviews conducted at the start and end of a 12-week semester. These interviews offer an in-depth look into the individual transition processes of six purposefully selected students who represent a range of backgrounds and varying degrees of success in EMI, including both international and local students. The findings indicate that English proficiency alone does not guarantee a successful transition into EMI. Other factors play crucial roles in the rate and extent to which students overcome transitional challenges. The study recognises the need for ongoing support to help students navigate persistent transitional challenges in EMI. Implications are discussed regarding language support, EMI curriculum planning, and future research directions. • The study offers in-depth insights through the lens of six selected students. • English proficiency, while crucial, is not the sole determinant of success in EMI. • Familiarity with EMI and academic conventions impacts transitional difficulties. • Transitional challenges were largely mitigated by the end of the semester. • Language support must be tailored and ongoing to cater to students' evolving needs. [ABSTRACT FROM AUTHOR]

In volume transmission (or neuromodulation) neurons do not make one-to-one connections to other neurons, but instead simply release neurotransmitter into the extracellular space from numerous varicosities. Many well-known neurotransmitters including serotonin (5HT), dopamine (DA), histamine (HA), Gamma-Aminobutyric Acid (GABA) and acetylcholine (ACh) participate in volume transmission. Typically, the cell bodies are in one volume and the axons project to a distant volume in the brain releasing the neurotransmitter there. We introduce volume transmission and describe mathematically two natural homeostatic mechanisms. In some brain regions several neurotransmitters in the extracellular space affect each other's release. We investigate the dynamics created by this comodulation in two different cases: serotonin and histamine; and the comodulation of 4 neurotransmitters in the striatum and we compare to experimental data. This kind of comodulation poses new dynamical questions as well as the question of how these biochemical networks influence the electrophysiological networks in the brain. [ABSTRACT FROM AUTHOR]

Sulphur is a highly reactive element, and is therefore able to enter into a great variety of chemical combinations, resulting in the formation of compounds of widely differing properties. Reactions involving sulphur, and the compounds which they produce, have stimulated and inspired people throughout the ages. Sulphur has always been associated with volcanoes, fires and smells. However, its story goes much further. Sulphur is present in thousands of products of the chemical industry, which are in everyday use. These include car batteries, car tyres, matches, paints, paper, textiles, food, detergents and pharmaceuticals. In part 1 of this essay, the evolution of the role of sulphur in the history of mankind is explained, through the eyes of etymology, geology, literature, art, and chemistry. In part 2 the role of sulphur in biochemistry and chemical technology is reviewed. In so doing, a case is established, to show that sulphur is the most extraordinary substance known to Man. [ABSTRACT FROM AUTHOR]

The Yidun Terrane hosts huge amounts of Late Triassic granitic plutons. While the southern Yidun Terrane, also referred to as the Zhongdian arc, mainly includes Late Triassic porphyry and related porphyry Cu-Au deposits, rare mineralization was found related to the contemporary granitic batholiths in the northern Yidun terrane (NYT). This paper has explored the chemical compositions of the apatite from these intrusions, which provide insights into the petrogenesis and the mineralization potential. The higher Mg and V concentrations and La/Sm ratios of the Zhongdian apatite than the Cuojiaoma and Daocheng apatite in the NYT suggestes that the Zhongdian porphyries were derived from a mixed source with both mantle and crustal contributions, while the Cuojiaoma and Daocheng granites are dominantly crustal derived. Compared with the Cuojiaoma and Daocheng apatite, the Zhongdian apatite are characterized by higher Sr, Eu/Eu* [EuN/(SmN×GdN)0.5], S and Cl, and low Mn and Y concentrations with adakitic affinity, indicating an environment with high oxygen fugacity and S and Cl contents for their parental magmas, which is favorable for the formation of porphyry Cu-Au deposits. By comparing the chemical characteristics of apatite from the ore-bearing porphyries and ore-barren granites in the Yidun Terrane, this study proposes that the apatite from the ore-bearing rocks commonly has relatively high Sr, S and Fe concentrations and low Mn, Y and Si/S ratio. These geochemical characteristics can be good indicators for predicting the metallogenic potential of the rocks. [ABSTRACT FROM AUTHOR]

Groundwater discharge into streams influences the biodiversity and health of groundwater-dependent stream ecosystems. These localized upwelling zones may act as biodiversity hotspots, or areas with a heightened amount of endemic species richness and abundance when compared to the surrounding locality. This input water creates environments with unique chemical compositions and water temperatures that serve as ideal habitat for various species within the ecosystem. Although difficult to identify and sample, these underwater groundwater–surface water interaction zones are important for fish spawning, benthic macroinvertebrate biodiversity, microbial communities, and aquatic and riparian vegetation. In this review, we highlight the groundwater characteristics that influence stream biodiversity and community structure. We argue for the importance of increased research on biodiversity indicators of groundwater upwelling zones as well as more public involvement through citizen science practices on the indirect and direct relationships between groundwater and dependent stream ecosystems. The unique characteristics that differentiate groundwater from surface water in a stream environment can be ideal conditions for fish, benthic macroinvertebrates, vegetation, and bacteria. Groundwater upwelling zones act as biodiversity hotspots that may have a key role in the overall health of a stream community. Research that revolves around groundwater-stream interactions is limited and difficult to accomplish, with no standardized hydrologic or ecological methods of measurement. It is crucial to not only make measurement collection practices and data interpretation commonplace but increase awareness of the relationship between groundwater-stream interactions and biodiversity hotspots. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) was recognized as a gaseous signaling molecule, similar to nitric oxide (-NO) and carbon monoxide (CO). The aim of this review is to provide an overview of the formation of hydrogen sulfide (H2S) in the human body. H2S is synthesized by enzymatic processes involving cysteine and several enzymes, including cystathionine-β-synthase (CBS), cystathionine-γ-lyase (CSE), cysteine aminotransferase (CAT), 3-mercaptopyruvate sulfurtransferase (3MST) and D-amino acid oxidase (DAO). The physiological and pathological effects of hydrogen sulfide (H2S) on various systems in the human body have led to extensive research efforts to develop appropriate methods to deliver H2S under conditions that mimic physiological settings and respond to various stimuli. These functions span a wide spectrum, ranging from effects on the endocrine system and cellular lifespan to protection of liver and kidney function. The exact physiological and hazardous thresholds of hydrogen sulfide (H2S) in the human body are currently not well understood and need to be researched in depth. This article provides an overview of the physiological significance of H2S in the human body. It highlights the various sources of H2S production in different situations and examines existing techniques for detecting this gas. [ABSTRACT FROM AUTHOR]

Sporomorphs (pollen and spores) are a mainstay of research into past vegetation, and increasingly sporomorph chemistry is being used as a palaeoecological tool. To make extant sporomorphs directly comparable to fossil specimens, fresh material is processed to remove labile compounds and isolate the sporopollenin wall. A range of processing approaches are currently in use, but the chemistries produced by these different techniques have not yet been compared across a range of taxa. It is therefore not clear how they compare in terms of efficiently isolating sporopollenin without changing its chemical structure, and what impact they have on relative chemical similarities and differences among taxa (i.e. whether more closely related species will always appear chemically more similar, regardless of how they have been processed). Here, we test this by applying five different processing approaches to sporomorphs from 15 taxa from across the vascular plant phylogeny. We show that each approach has its own idiosyncrasies in terms of impacts on sporomorph chemistry. For the most part a common pattern of among‐taxon chemical variability is uncovered, and a phylogenetic signal within sporopollenin chemistry is supported. Working with spectral derivatives generally increases agreement among the different processing approaches, but decreases the strength of the phylogenetic signal. No one processing approach is ideal, and the choice of which to use is likely to depend on the goal of the study, the type and quantity of material being processed, and the laboratory facilities available for processing. [ABSTRACT FROM AUTHOR]

The aim of the current research is to identify the concepts of sustainable development that should be included in the content of chemistry books at the secondary stage (course system) in light of the goals of sustainable development 2030, and to reveal the extent to which they are included in the content of the energy unit and chemical changes of those books, and to develop the unit in light of that. To achieve these goals, the research followed the descriptive analytical approach. For this, a card was prepared for content analysis, which included a list of proposed concepts and their indicators. One of the most prominent results that was reached was the scarcity of including scientific concepts related to sustainable development in chemistry books for the secondary level, the course system. In light of this, some concepts were suggested to be included in the content of the research sample books. Including: concepts of renewable energy, energy efficiency and its devices, clean industries, clean energy, energy production from waste, and pollution and its reduction. The research also presented a developed unit in energy and chemical changes based on these results. [ABSTRACT FROM AUTHOR]

A series of pseudorotaxanes with supramolecular organometallic silver(I) and gold(I) pillarplexes acting as rings and different α,ω‐dicarboxylic acids as axle components are reported. The successful formation of the host‐guest complexes is shown by 1H NMR spectroscopy and respective NMR titration. Additional evaluation with ITC titration experiments yielded dissociation constants (Kd) ranging from 10−5 to 10−7 M. Single‐crystal X‐Ray diffraction analysis reveals a particularly exciting pore alignment of different examples in the solid state depending on the length of the guest. The work highlights, that dicarboxylic acids can penetrate the tight tubular pillarplex pore, paving the way to future mechanically interlocked molecules and materials. [ABSTRACT FROM AUTHOR]

A strong revival of interest has been dedicated to peptides over the last few years, in different fields including drug discovery, biosensing and material sciences. The use of dynamic covalent chemistry has allowed the development of self‐adaptative peptides or peptidomimetics, responsive to their environment. The development of methods allowing the building, screening or deconvolution of libraries of peptides is a highly active research area and dynamic combinatorial chemistry represents an innovative and underexploited method in this field. This Review gives an overview of the use of dynamic covalent chemistry as a tool to produce peptides or peptidomimetics, with particular attention to applications in dynamic combinatorial chemistry. [ABSTRACT FROM AUTHOR]

A three‐component molecular ensemble consisting of the constitutionally dynamic cage 1, rotaxane 2 and luminophore 3 acts as a signal transducer which assimilates three input signals, i. e. Zn2+, H+, and Cu+, to perform individual logic operations (e. g. a 3‐input NOR gate with catalytic output, 3‐input AND gate with optical output) and operates as an unconventional 3‐input demultiplexer. [ABSTRACT FROM AUTHOR]

Are the ways of engaging with the world that students develop through higher education particular to bodies of knowledge they study? In this article, we examine how students' accounts of the discipline of chemistry in England and South Africa changed over the three years of their undergraduate degrees. Based on a longitudinal phenomenographic analysis of 105 interviews with 33 chemistry students over the course of their undergraduate degrees in four institutions, we constituted five qualitatively different ways of describing chemistry. These ranged from chemistry as something that happens when things are mixed in a laboratory to a more inclusive account that described chemistry as being able to explain molecular interactions in unfamiliar environments. Most students expressed more inclusive accounts of chemistry by the end of their degrees and the level of change appeared to be related to their educational experiences. In contrast to approaches that emphasise the generic student outcomes from higher education, these findings highlight the importance of recognising the distinctive outcomes that students gain from their engagement with particular bodies of disciplinary knowledge. It further highlights the importance of students understanding their degrees as an educational experience that requires them to commit to engaging with these bodies of knowledge. [ABSTRACT FROM AUTHOR]

Fat replacers are added to food to provide some or all of the functional properties of natural fat while providing fewer calories. The majority of fat-based replacers are either low-calorie fats that include chemically altered triglycerides or fat substitutes (i.e., lipid analogs that are neither hydrolyzed nor absorbed by the body as natural fat). This review capitalizes on fat substitutes of different origins in the context of their different chemical synthesis, lowering calorie mechanisms, nutritional benefits, metabolism, and safety reports of these substitutes in humans are dissected for the first time in relation to their metabolic byproducts inside humans. Besides, their functional properties and recent advances in pharma-food applications are reviewed. Fat substitutes offer a trendy replacer with less health risks compared to conventional fats. Their different structural chemical classes exert their low-calorie actions under different action mechanisms like emulsification or modification as structured lipids. Regarding their metabolism, they can retard the absorption of some nutrients acting as anti-nutrients, while their biotransformation products inside the colon might affect microbiota activity or predominance. Fat substitutes offer multiple functions in food processing, using them as preservatives and developing therapeutic tailor-made fat substitutes are the futuristic directions without their current side effects, especially if consumed regularly. [ABSTRACT FROM AUTHOR]