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1.
Chem Commun (Camb) ; 60(50): 6431-6434, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38829284

ABSTRACT

The preparation of highly rigid cobalt(II)- and copper(II)-organic frameworks incorporating a tetralactam [2]rotaxane as a ligand is described. The interlocked ligand is functionalized with two pairs of carboxylate groups placed at each counterpart, thus limiting its dynamics within the crystal. The solid structure of the metal-organic rotaxane frameworks showed different, unprecedented polycatenation modes of grids, depending on the employed metal, providing great rigidity to the structures. This rigidity has been evaluated by using single crystal X-ray diffraction analyses of the cobalt(II)-organic frameworks embedded in different solvents, observing that the lattices remain unchanged. Thus, this research demonstrates that rigid and robust materials with permanent porosity can be achieved using dynamic ligands.

2.
Int J Biol Macromol ; 267(Pt 2): 131513, 2024 May.
Article in English | MEDLINE | ID: mdl-38608979

ABSTRACT

Tyrosinase is a copper oxidase enzyme which catalyzes the first two steps in the melanogenesis pathway, L-tyrosine to L-dopa conversion and, then, to o-dopaquinone and dopachrome. Hypopigmentation and, above all, hyperpigmentation issues can be originated depending on their activity. This enzyme also promotes the browning of fruits and vegetables. Therefore, control of their activity by regulators is research topic of great relevance. In this work, we consider the use of inhibitors of monophenolase and diphenolase activities of the enzyme in order to accomplish such control. An experimental design and data analysis which allow the accurate calculation of the degree of inhibition of monophenolase activity (iM) and diphenolase activity (iD) are proposed. The IC50 values (amount of inhibitor that causes 50 % inhibition at a fixed substrate concentration) can be calculated for the two activities and from the values of IC50M (monophenolase) and IC50D(diphenolase). Additionally, the strength and type of inhibition can be deduced from these values. The data analysis from these IC50D values allows to obtain the values of [Formula: see text] or [Formula: see text] , or and [Formula: see text] from the values of IC50M. In all cases, the values of the different must satisfy their relationship with IC50M and IC50D.


Subject(s)
Enzyme Inhibitors , Monophenol Monooxygenase , Monophenol Monooxygenase/antagonists & inhibitors , Monophenol Monooxygenase/metabolism , Monophenol Monooxygenase/chemistry , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Inhibitory Concentration 50 , Kinetics , Oxidoreductases/antagonists & inhibitors , Oxidoreductases/metabolism , Humans
3.
J Am Chem Soc ; 146(5): 2882-2887, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38266249

ABSTRACT

Herein we describe an effective transmission of chirality, from mechanically planar chirality to point chirality, in hydrogen-bonded [2]rotaxanes. A highly selective mono-N-methylation of one (out of four) amide N atom at the macrocyclic counterpart of starting achiral rotaxanes generates mechanically planar chirality. Followed by chiral resolution, both enantiomers were subjected to a base-promoted intramolecular cyclization, where their interlocked threads were transformed into new lactam moieties. As a matter of fact, the mechanically planar chiral information was effectively transferred to the resulting stereocenters (covalent chirality) of the newly formed heterocycles. Upon removing the entwined macrocycle, the final lactams were obtained with high enantiopurity.

4.
Med Biol Eng Comput ; 62(1): 257-273, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37789249

ABSTRACT

The integration of IoT in healthcare has introduced vulnerabilities in medical devices and software, posing risks to patient safety and system integrity. This study aims to bridge the research gap and provide valuable insights for addressing healthcare vulnerabilities and their mitigation mechanisms. Software vulnerabilities related to health systems from 2001 to 2022 were collected from the National Vulnerability Database (NVD) systematized by software developed by the researchers and assessed by a medical specialist for their impact on patient well-being. The analysis revealed electronic health records, wireless infusion pumps, endoscope cameras, and radiology information systems as the most vulnerable. In addition, critical vulnerabilities were identified, including poor credential management and hard-coded credentials. The investigation provides some insights into the consequences of vulnerabilities in health software products, projecting future security issues by 2025, offers mitigation suggestions, and highlights trends in attacks on life support and health systems are also provided. The healthcare industry needs significant improvements in protecting medical devices from cyberattacks. Securing communication channels and network schema and adopting secure software practices is necessary. In addition, collaboration, regulatory adherence, and continuous security monitoring are crucial. Industries, researchers, and stakeholders can utilize these findings to enhance security and safeguard patient safety.


Subject(s)
Computer Security , Software , Humans , Delivery of Health Care
5.
Org Biomol Chem ; 21(45): 9070-9075, 2023 Nov 22.
Article in English | MEDLINE | ID: mdl-37938860

ABSTRACT

In this study, we show the effect of the gem-dimethyl substitution at the four benzylic carbons of the ring on the internal dynamics of two-station [2]rotaxanes. Such structural modification of the polyamide macrocycles promotes a drastic change of the internal dynamics as shown by variable-temperature (VT) 1H NMR experiments. We determined that the shuttling rates of the octamethylated macrocycle along a series of symmetrical threads were significantly faster compared to the non-substituted ring. This effect was particularly pronounced in the fumaramide-based system, in which the rate was 27 times faster than that of the model system.

6.
J Chem Educ ; 100(9): 3355-3363, 2023 Sep 12.
Article in English | MEDLINE | ID: mdl-37720524

ABSTRACT

The synthesis of a [2]rotaxane through three- or five-component coupling reactions has been adapted to an organic chemistry experiment for upper-division students. The experimental procedure addresses the search for the most favorable reaction conditions for the synthesis of the interlocked compound, which is obtained in a yield of up to 71%. Moreover, the interlocked nature of the rotaxane is proven by NMR spectroscopy. The content of the sessions has been designed on the basis of a proactive methodology whereby upper-division undergraduate students have a dynamic role. The laboratory experience not only introduces students to the chemistry of the mechanical bond but also reinforces their previous knowledge of basic organic laboratory procedures and their skills with structural elucidation techniques such as NMR and FT-IR spectroscopies. The experiment has been designed in such a customizable way that both experimental procedures and laboratory material can be adapted to a wide range of undergraduate course curricula.

7.
Chem Sci ; 14(15): 4143-4151, 2023 Apr 12.
Article in English | MEDLINE | ID: mdl-37063802

ABSTRACT

The synthesis of a ditopic interlocked building-block and its self-assembly into a cyclic dimer is reported herein. Starting from a thread with two recognition sites, a three-component clipping reaction was carried out to construct a bistable [2]rotaxane. A subsequent Suzuki cross-coupling reaction allowed the connection of a second ring to that of the rotaxane, affording a self-complementary ditopic system. NMR studies were carried out to identify a cyclic hetero[4]pseudorotaxane as the main supramolecular structure in solution. Its assembly is the result of a positive cooperativity operating in the hydrogen-bonding-driven assembly of this mechanically interlocked supramolecule, as revealed by computational studies. The increase of the polarity of the solvent allows the disruption of the intercomponent interactions and the disassembly of the hetero[4]pseudorotaxane into the two interlocked units. The disassembly of the cyclic dimer was also achieved through a Diels-Alder reaction over the fumaramide binding site of the thread, triggering the translational motion of the entwined macrocycle to an adjacent glycylglycine-based station and precluding the supramolecular dimerization. The competitive molecular recognition of a guest molecule by one of the self-templating counterparts of the dimer also led to the controlled disassembly of the hetero[4]pseudorotaxane.

8.
Angew Chem Int Ed Engl ; 62(21): e202302681, 2023 May 15.
Article in English | MEDLINE | ID: mdl-36952651

ABSTRACT

Glutaconamide-based [2]rotaxanes are efficiently oxidized to the respective interlocked α-ketoamides, whereas their non-interlocked threads afford hydroxycyclohexene tetraamides under similar reaction conditions. These results showcase the mechanically interlocking of highly reactive substrates as a powerful tool for controlling their chemical behavior. Inside the macrocycle and under irradiation with light, the α-ketoamide threads convert, in a divergent manner, into the corresponding interlocked hydroxy-ß-lactams or oxazolidinones by two modes of Norrish/Yang type-II intramolecular cyclizations, processes that are efficiently chemocontrolled by the mechanical bond.

9.
Int J Mol Sci ; 24(4)2023 Feb 20.
Article in English | MEDLINE | ID: mdl-36835605

ABSTRACT

We report the molecular characterization of an ethyl methanesulfonate (EMS)-induced mutation that causes albinism and lethality at the seedling stage in Arabidopsis thaliana. We identified the mutation using a mapping-by-sequencing approach that uses Fisher's exact tests to detect changes in allele frequencies among the seedlings of an F2 mapping population, which had been pooled according to their phenotypes (wild-type or mutant). After purifying genomic DNA from the plants of both pools, the two samples were sequenced using the Illumina HiSeq 2500 next-generation sequencing platform. The bioinformatic analysis allowed us to identify a point mutation that damages a conserved residue at the acceptor site of an intron of the At2g04030 gene, which encodes the chloroplast-localized AtHsp90.5 protein, a member of the HSP90 family of heat shock proteins. Our RNA-seq analysis demonstrates that the new allele alters the splicing of At2g04030 transcripts in multiple ways, leading to massive deregulation of genes encoding plastid-localized proteins. A search for protein-protein interactions using the yeast two-hybrid method allowed us to identify two members of the GrpE superfamily as potential interactors of AtHsp90.5, as has previously been reported for green algae.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Arabidopsis/genetics , Mutation , Arabidopsis Proteins/genetics , Chloroplasts/metabolism , Seedlings/metabolism , Cloning, Molecular , Gene Expression Regulation, Plant
10.
Int J Mol Sci ; 23(23)2022 Dec 01.
Article in English | MEDLINE | ID: mdl-36499424

ABSTRACT

trans-Resveratrol can be catabolized by the gut microbiota to dihydroresveratrol, 3,4'-dihydroxy-trans-stilbene, lunularin, and 4-hydroxydibenzyl. These metabolites can reach relevant concentrations in the colon. However, not all individuals metabolize RSV equally, as it depends on their RSV gut microbiota metabotype (i.e., lunularin producers vs. non-producers). However, how this microbial metabolism affects the cancer chemopreventive activity of stilbenes and their microbial metabolites is poorly known. We investigated the structure-antiproliferative activity relationship of dietary stilbenes, their gut microbial metabolites, and various analogs in human cancer (Caco-2 and HT-29) and non-tumorigenic (CCD18-Co) colon cells. The antiproliferative IC50 values of pterostilbene, oxy-resveratrol, piceatannol, resveratrol, dihydroresveratrol, lunularin, 3,4'-dihydroxy-trans-stilbene, pinosylvin, dihydropinosylvin, 4-hydroxy-trans-stilbene, 4-hydroxydibenzyl, 3-hydroxydibenzyl, and 4-trans-stilbenemethanol were calculated. IC50 values were correlated with 34 molecular characteristics by bi- and multivariate analysis. Little or no activity on CCD18-Co was observed, while Caco-2 was more sensitive than HT-29, which was explained by their different capacities to metabolize the compounds. Caco-2 IC50 values ranged from 11.4 ± 10.1 µM (4-hydroxy-trans-stilbene) to 73.9 ± 13.8 µM (dihydropinosylvin). In HT-29, the values ranged from 24.4 ± 11.3 µM (4-hydroxy-trans-stilbene) to 96.7 ± 6.7 µM (4-hydroxydibenzyl). At their IC50, most compounds induced apoptosis and arrested the cell cycle at the S phase, pterostilbene at G2/M, while 4-hydroxy-trans-stilbene and 3,4'-dihydroxy-trans-stilbene arrested at both phases. Higher Connolly values (larger size) hindered the antiproliferative activity, while a lower pKa1 enhanced the activity in Caco-2, and higher LogP values (more hydrophobicity) increased the activity in HT-29. Reducing the styrene double bond in stilbenes was the most critical feature in decreasing the antiproliferative activity. These results (i) suggest that gut microbiota metabolism determines the antiproliferative effects of dietary stilbenes. Therefore, RSV consumption might exert different effects in individuals depending on their gut microbiota metabotypes associated with RSV metabolism, and (ii) could help design customized drugs with a stilbenoid and (or) dibenzyl core against colorectal cancer.


Subject(s)
Colonic Neoplasms , Gastrointestinal Microbiome , Stilbenes , Humans , Caco-2 Cells , Stilbenes/chemistry , Resveratrol/pharmacology , Colonic Neoplasms/drug therapy , Structure-Activity Relationship
11.
J Agric Food Chem ; 70(34): 10521-10531, 2022 Aug 31.
Article in English | MEDLINE | ID: mdl-35981285

ABSTRACT

We describe here for the first time the consistent observation of two metabotypes associated with resveratrol metabolism by the human gut microbiota, that is, lunularin (LUNU)-producers and LUNU non-producers. In healthy volunteers (n = 195), resveratrol was reduced to dihydroresveratrol, which only in the LUNU-producer metabotype was sequentially dehydroxylated at the 5-position to yield LUNU and the 3-position to produce 4-hydroxydibenzyl. These metabolites (also 3,4'-dihydroxy-trans-stilbene in some LUNU-producers) were detected in the urine and (or) feces of 74% of volunteers after consuming resveratrol, while 26% lacked these dehydroxylase activities. The LUNU non-producer metabotype was more prevalent in females (P < 0.05) but independent of individuals' BMI and age. A 4-styrylphenol reductase in both metabotypes converted stilbenes to their corresponding dibenzyls, while no 4-dehydroxylation in stilbenes or dibenzyls was observed. 4-Hydroxy-trans-stilbene, pinosylvin, dihydropinosylvin, 3-hydroxydibenzyl, and 3-hydroxy-trans-stilbene were not detected in vivo or in vitro. Further research on LUNU metabotypes, their associated gut microbiota, and their impact on health is worthwhile.


Subject(s)
Gastrointestinal Microbiome , Stilbenes , Bibenzyls , Female , Humans , Phenols , Resveratrol , Stilbenes/metabolism
12.
Angew Chem Int Ed Engl ; 61(39): e202209904, 2022 09 26.
Article in English | MEDLINE | ID: mdl-35916122

ABSTRACT

The synthesis of chiral mechanically interlocked molecules has attracted a lot of attention in the last few years, with applications in different fields, such as asymmetric catalysis or sensing. Herein we describe the synthesis of orientational mechanostereoisomers, which include a benzylic amide macrocycle with a stereogenic center, and nonsymmetric N-(arylmethyl)fumaramides as the axis. The base-promoted cyclization of the initial fumaramide thread allows enantioenriched value-added compounds, such as lactams of different ring sizes and amino acids, to be obtained. The chiral information is effectively transmitted across the mechanical bond from the encircling ring to the interlocked lactam. High levels of enantioselectivity and full control of the regioselectivity of the final cyclic compounds are attained.


Subject(s)
Rotaxanes , Amides , Amino Acids , Lactams , Molecular Structure , Rotaxanes/chemistry
13.
An. pediatr. (2003. Ed. impr.) ; 97(2): 103-111, ago, 2022. tab, graf
Article in English, Spanish | IBECS | ID: ibc-207560

ABSTRACT

Introducción: La hipogammaglobulinemia en los primeros meses postrasplante de progenitores hematopoyéticos (TPH) es común en pacientes pediátricos. Durante esta fase se debe administrar tratamiento sustitutivo con inmunoglobulina humana por vía parenteral para la prevención de infecciones. En algunos casos, esta hipogammaglobulinemia persiste en el tiempo, lo que obliga a prolongar el tratamiento cuando el paciente ya no suele ser portador de una vía central, por lo que son candidatos ideales para el tratamiento de reemplazo por vía subcutánea. Existe escasa bibliografía publicada que describa el uso de esta vía en pacientes pediátricos sometidos a TPH; sin embargo, está ampliamente descrita y con muy buenos resultados en el tratamiento de reemplazo en los niños con inmunodeficiencias primarias. Pacientes y métodos: Se realiza un estudio observacional, descriptivo y longitudinal de carácter retrospectivo. Durante los años 2008-2019 se evalúan a todos los pacientes pediátricos sometidos a TPH en nuestro centro que presentan una hipogammaglobulinemia crónica persistente (superior a un año). Se evalúa la fase de tratamiento con inmunoglobulina intravenosa (Privigen®) y los primeros 4 años de tratamiento con inmunoglobulina subcutánea (Hizentra®) mediante un cuestionario. Resultados: Durante los años 2008-2019 se han realizado en nuestro centro 175 trasplantes de precursores hematopoyéticos, de los cuáles 143 (82%) superaron los 3 meses postrasplante. De estos, 3 (2%) pacientes presentaron una hipogammaglobulinemia persistente. Los 3 comparten factores descritos en la bibliografía involucrados en la reconstitución inmune. Mediante el cuestionario se observa que el cambio de gammaglobulina intravenosa a subcutánea ha supuesto una gran mejoría en la calidad de vida de los pacientes. (AU)


Introduction: Hypogammaglobulinemia in the first months after allogeneic hematopoietic stem cell transplantation (HSCT) is common in pediatric patients. During this phase, replacement therapy with human immunoglobulin must be administered parenterally to prevent infections. In some cases, this hypogammaglobulinemia persists over time, which forces further treatment when the patient is usually no longer a carrier of a central line, making them ideal candidates for subcutaneous replacement therapy. There is little published literature describing the use of this method in pediatric patients undergoing HSCT, widely described in replacement treatment in children with primary immunodeficiencies with very good results. Patients and methods: An observational, descriptive, longitudinal and retrospective study is carried out. During the years 2008–2019, we evaluated all pediatric patients undergoing HSCT in our center with persistent chronic hypogammaglobulinemia (for over a year). The treatment phase with intravenous immunoglobulin (Privigen®) and the first four years of treatment with subcutaneous immunoglobulin (Hizentra®) are evaluated using a questionnaire. Results: During the years 2008-2019, 175 patients underwent HSCT, 143 (82%) of whom exceeded three months after transplantation. 3 (2%) of them had persistent hypogammaglobulinemia. All three share factors described in the literature involved in immune reconstitution. After analyzing the questionnaire, it is observed that switching from intravenous to subcutaneous gammaglobulin has involved a great improvement in their quality of life. (AU)


Subject(s)
Humans , Infant, Newborn , Infant , Child, Preschool , Child , Adolescent , Agammaglobulinemia/drug therapy , Hematinics , gamma-Globulins , Longitudinal Studies , Epidemiology, Descriptive , Surveys and Questionnaires , Immunoglobulin G
14.
Article in English | MEDLINE | ID: mdl-35897314

ABSTRACT

Teleworking is an everyday reality in today's world. Many companies are opting for this way of working remotely, as it improves employers' satisfaction along with the work-life balance and it does not lead to any significant reduction in performance. In general, the comfortable use of software applications is a priority, and quality aspects such as usability are of vital importance. In this paper, a novel workflow is proposed. It consists of the following components: (1) a tool to manage usability evaluations based on expert reviews, called Usevalia; (2) a set of heuristics to be considered when performing the evaluations; (3) a catalogue of usability requirements to guide the evaluations; (4) a checklist related to the heuristics to verify that the evaluations have been performed correctly by all the auditors; and (5) a set of tasks to know in advance the functionality of the applications to be audited. Personal health records (PHRs) were taken as a case study. This methodology made it possible to involve a total of 31 working groups that evaluated the usability of four PHRs. Concerning the main results, the evaluators agreed that with Usevalia the usability evaluations could go a step further because they are coordinated and can work together remotely. In addition, analyses of usability scores provided insight into current proposals for improving usability of applications.


Subject(s)
Health Records, Personal , Checklist , Heuristics , Software , User-Computer Interface , Workflow
15.
An Pediatr (Engl Ed) ; 97(2): 103-111, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35869014

ABSTRACT

INTRODUCTION: Hypogammaglobulinemia in the first months after allogeneic hematopoietic stem cell transplantation (HSCT) is common in paediatric patients. During this phase, replacement therapy with human immunoglobulin must be administered parenterally to prevent infections. In some cases, this hypogammaglobulinemia persists over time, which forces further treatment when the patient is usually no longer a carrier of a central line, making them ideal candidates for subcutaneous replacement therapy. There is little published literature describing the use of this method in paediatric patients undergoing HSCT, widely described in replacement treatment in children with primary immunodeficiencies with very good results. PATIENTS AND METHODS: An observational, descriptive, longitudinal and retrospective study is carried out. During the years 2008-2019, we evaluated all paediatric patients undergoing HSCT in our center with persistent chronic hypogammaglobulinemia (for over a year). The treatment phase with intravenous immunoglobulin (Privigen®) and the first four years of treatment with subcutaneous immunoglobulin (Hizentra®) are evaluated using a questionnaire. RESULTS: During the years 2008-2019, 175 patients underwent HSCT, 143 (82%) of whom exceeded three months after transplantation. Three (2%) of them had persistent hypogammaglobulinemia. All three share factors described in the literature involved in immune reconstitution. After analysing the questionnaire, it is observed that switching from intravenous to subcutaneous gammaglobulin has involved a great improvement in their quality of life. CONCLUSIONS: The origin of chronic hypogammaglobulinemia in our patients shows different factors and cannot be attributed to a single cause. Due to the limited number of patients no conclusions can be drawn at the population level. We have been able to observe that replacement treatment with Hizentra 20% has been as effective as the intravenous administration without evidence of an increase in bacterial infections. Furthermore, it has also led to an improvement in quality of life and increased comfort, as the patients themselves have stated.


Subject(s)
Agammaglobulinemia , Graft vs Host Disease , Hematopoietic Stem Cell Transplantation , Agammaglobulinemia/etiology , Agammaglobulinemia/therapy , Child , Graft vs Host Disease/complications , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Immunoglobulins, Intravenous/therapeutic use , Quality of Life , Retrospective Studies
16.
Chem Soc Rev ; 51(12): 4949-4976, 2022 Jun 20.
Article in English | MEDLINE | ID: mdl-35612363

ABSTRACT

Mechanically interlocked molecules (MIMs) have great potential in the development of molecular machinery due to their intercomponent dynamics. The incorporation of these molecules in a condensed phase makes it possible to take advantage of the control of the motion of the components at the macroscopic level. Metal-organic frameworks (MOFs) are postulated as ideal supports for intertwined molecules. This review covers the chemistry of the mechanical bond incorporated into metal-organic frameworks from the seminal studies to the latest published advances. We first describe some fundamental concepts of MIMs and MOFs. Next, we summarize the advances in the incorporation of rotaxanes and catenanes inside MOF matrices. Finally, we conclude by showing the study of the rotaxane dynamics in MOFs and the operation of some stimuli-responsive MIMs within MOFs. In addition to emphasising some selected examples, we offer a critical opinion on the state of the art of this research field, remarking the key points on which the future of these systems should be focused.

17.
Comput Methods Programs Biomed ; 213: 106459, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34768233

ABSTRACT

BACKGROUND AND OBJECTIVE: This paper presents an empirical study of a gamified mobile-based assessment approach that can be used to engage students and improve their educational performance. METHOD: A gamified audience response system called G-SIDRA was employed. Three gamification elements were used to motivate students in classroom activities: badges for achievements to increase engagement, points to indicate progression and performance in the subject and ranking for promoting competitiveness. A total of 90 medical students in a General and Descriptive Anatomy of the Locomotor System course were taught using G-SIDRA in the academic year 2019/2020. Smart bracelets were configured to collect heart rate measurements from 30 students with the aim of evaluating the impact of the gamification elements. The control group consisted of a sample of 110 students enrolled on the same course in the academic year 2016/2017 using non-gamified SIDRA. RESULTS: Statistically significant differences were found between multiple choice questions (MCQ) scores obtained by using SIDRA and G-SIDRA in the four experiments (U = 1.621,50, p < 0,01 for Exp1; U = 1.950,00, p < 0,01 for Exp2; U = 955,00, p < 0,01 for Exp3; U = 2.335,00, p < 0,01 for Exp4). In the students' final exam grades, statistically significant differences between students that used G-SIDRA as opposed to SIDRA (T(157) = 3.992; p = 0.044) were obtained. Concerning gamification elements, statistically significantly differences were found in comparing the pulse increases after and before the badge event in the four experiments (U = 2.484,00, p = 0,038 for Exp1; U = 2.109,50, p = 0,046 for Exp2; U = 1.790,50, p = 0,025 for Exp3; U = 1.557,0, p = 0,048 for Exp4). However, there are not statistically significant differences between the pulse increases after and before the ranking event in the four experiments. In a 5-point Likert-type scale, the students expressed satisfaction with G-SIDRA (M = 4.552) and thought the system helped to better understand both theoretical and practical concepts (M = 4.092). Their global assessment of the G-SIDRA platform was 4.471. CONCLUSIONS: Of the three gamification elements used in the study, only badge has an effect on heart rate. Better student responses and academic performance were achieved when using G-SIDRA. Nevertheless, more research is required to evaluate the impact of the gamification elements on the motivation, engagement and performance of students. Physiological measures are promising approaches for gamification elements evaluation.


Subject(s)
Gamification , Motivation , Heart Rate , Humans
18.
Chem Commun (Camb) ; 58(2): 290-293, 2021 Dec 23.
Article in English | MEDLINE | ID: mdl-34881747

ABSTRACT

Self-templating two-component coupling reactions allowed the isolation of two threaded products with different molecular sizes: a lasso-type [1]rotaxane and a [c2]daisy chain rotaxane. Their distribution in the final reaction mixture varies as a factor of the concentration of the reactants. Through this methodology we obtained a large 84-membered cyclic multistation [2]rotaxane.

19.
Article in English | MEDLINE | ID: mdl-34948818

ABSTRACT

This paper presents three experiments to assess the impact of gamifying an audience response system on the perceptions and educational performance of students. An audience response system called SIDRA (Immediate Audience Response System in Spanish) and two audience response systems with gamification features, R-G-SIDRA (gamified SIDRA with ranking) and RB-G-SIDRA (gamified SIDRA with ranking and badges), were used in a General and Descriptive Human Anatomy course. Students participated in an empirical study. In the academic year 2019-2020, a total of 90 students used RB-G-SIDRA, 90 students employed R-G-SIDRA in the academic year 2018-2019, and 92 students used SIDRA in the academic year 2017-2018. Statistically significant differences were found between final exam grades obtained by using RB-G-SIDRA and SIDRA, U = 39.211 adjusted p = 0.001 and RB-G-SIDRA and R-G-SIDRA U = 31.157 adjusted p = 0.015, thus finding strong evidence with respect to the benefit of the badges used in RB-G-SIDRA. Moreover, in the students' SIDRA systems scores, statistically significant differences were found between RB-G-SIDRA and SIDRA, U = -90.521 adjusted p < 0.001, and between R-G-SIDRA and SIDRA, U = -87.998 adjusted p < 0.001. Significant correlations between individual and team scores were also found in all of the tests in RB-G-SIDRA and G-SIDRA. The students expressed satisfaction, engagement, and motivation with SIDRA, R-G-SIDRA, and RB-G-SIDRA, thus obtaining a final average assessment of 4.28, 4.61, and 4.47 out of 5, respectively. Students perform better academically with gamified versus non-gamified audience response systems. Findings can be used to build a gamified adaptive learning system.


Subject(s)
Academic Performance , Gamification , Humans , Learning , Motivation , Students
20.
J Org Chem ; 86(21): 15045-15054, 2021 11 05.
Article in English | MEDLINE | ID: mdl-34597042

ABSTRACT

The synthesis of a series of interlocked profragrances and the study of the controlled release of the corresponding scents are reported. The structures of the profragrances are based on a [2]pseudorotaxane scaffold with a fumaramate thread derived from perfumery alcohols and a tetrabenzylamido ring. The delivery of the scents was accomplished by sequential thermal dethreading and further enzymatic hydrolysis. Alternatively, the dethreading can be achieved by increasing the polarity of the solvent or photochemical isomerization. The temperature of dethreading can be modulated by the steric demand of the ends of the thread, which allows the selection of different precursor structures depending on the desired rates of delivery. The inputs and outputs for the controlled release of the interlocked profragrances correspond to those of YES or AND logic gates.


Subject(s)
Odorants , Rotaxanes , Delayed-Action Preparations
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