Students' foundational understanding of chemical reaction in the forensic science bachelor's degree program at the National Autonomous University of Mexico.

OBJECTIVE: To compare the understanding of the concept of chemical reaction-as operationalized by Bloom's taxonomy of cognitive levels-of students in forensic science bachelor's degree with that achieved by students majoring in chemistry, as a prerequisite for future professional collaboration and communication. MATERIALS AND METHODS: Using previously validated and published tests developed to assess students' knowledge, comprehension, and application of the concept of chemical reaction, we explored how conceptual understanding developed in students enrolled in (a) a forensic science degree program in a Mexican public university and in (b) chemistry undergraduate programs offered by the same university, and whether both groups achieved comparable attainment levels. FINDINGS AND IMPLICATIONS: Despite receiving considerably less chemical instruction, forensic science students achieved comparable levels of conceptual understanding of chemical reaction to those exhibited by chemistry students. This finding is encouraging because it might mean that future forensic scientists could graduate with a solid foundation of chemical knowledge. More research, particularly on the learning of other key concepts, will be needed to verify these initial findings.

Interdisciplinary approaches to the teaching of forensic science in the Forensic Science Undergraduate Program of the National Autonomous University of Mexico, before and after COVID-19.

In 2013, the Forensic Science Undergraduate Program (FSUP) at the National Autonomous University of Mexico was created in response to an alarming criminal situation in Mexico, as well as to the radical reform of its criminal justice system. Its mission is to educate and train ethical, critical, and humanistic forensic scientists capable of conducting inquiries that meet scientific quality standards and assist the justice system in firmly linking legal rulings to the available evidence. At the time, it was the first such program in the country, and the contributions that interdisciplinary forensic scientists could make to criminal investigations were largely unknown among forensic and legal practitioners. During its existence, providing an interdisciplinary, competence-based education to students has been one of the main challenges. To overcome it, teaching and assessment approaches-centered on the achievement of specifically forensic competencies as learning outcomes and the integration of forensic disciplines towards the resolution of simulated cases-have been devised to help develop the professional skill set expected of graduates. The COVID-19 pandemic led to adapting these approaches to distance or hybrid modes of learning, increasing their versatility and enriching the pedagogic repertoire of the FSUP. Currently, the main impact of the program lies in the successful incorporation of some of its graduates to agencies belonging to or related to the criminal justice system, such as the National Prosecutor's Office, the Commission for Truth and Justice for the Ayotzinapa Case, and the National Commission for the Search of Missing and Disappeared Persons, among others.

Maize Thymidine Kinase Activity Is Present throughout Plant Development and Its Heterologous Expression Confers Tolerance to an Organellar DNA-Damaging Agent.

Thymidine kinase 1 (TK1) phosphorylates thymidine nucleosides to generate thymidine monophosphate. This reaction belongs to the pyrimidine salvage route that is phylogenetically conserved. In the model plant Arabidopsis thaliana, TK activity contributes to maintain nuclear and organellar genome integrity by providing deoxythymidine-triphosphate (dTTP) for DNA synthesis. Arabidopsis has two TK1 genes (TK1a and TK1b) and double mutants show an albino phenotype and develop poorly. In contrast, maize (Zea mays L.) has a single TK1 (ZmTK1) gene and mutant plants are albino and display reduced genome copy number in chloroplasts. We studied the role of ZmTK1 during development and genotoxic stress response by assessing its activity at different developmental stages and by complementing Arabidopsis tk1 mutants. We found that ZmTK1 transcripts and activity are present during germination and throughout maize development. We show that ZmTK1 translocation to chloroplasts depends on a 72-amino-acid N-signal and its plastid localization is consistent with its ability to complement Arabidopsis tk1b mutants which are hypersensitive to ciprofloxacin (CIP), a genotoxic agent to organellar DNA. Also, ZmTK1 partly complemented the Arabidopsis double mutant plants during development. Our results contribute to the understanding of TK1 function in monocot species as an organellar enzyme for genome replication and repair.