Changes in executive function in the Canadian longitudinal study on aging over 3-years: A focus on social determinants of health

A genetic toolbox to empower Paracoccus pantotrophus DSM 2944 as a metabolically versatile SynBio chassis

BACKGROUND

To contribute to the discovery of new microbial strains with metabolic and physiological robustness and develop them into successful chasses, Paracoccus pantotrophus DSM 2944, a Gram-negative bacterium from the phylum Alphaproteobacteria and the family Rhodobacteraceae, was chosen. The strain possesses an innate ability to tolerate high salt concentrations. It utilizes diverse substrates, including cheap and renewable feedstocks, such as C1 and C2 compounds. Also, it can consume short-chain alkanes, predominately found in hydrocarbon-rich environments, making it a potential bioremediation agent. The demonstrated metabolic versatility, coupled with the synthesis of the biodegradable polymer polyhydroxyalkanoate, positions this microbial strain as a noteworthy candidate for advancing the principles of a circular bioeconomy.

RESULTS

The study aims to follow the chassis roadmap, as depicted by Calero and Nikel, and de Lorenzo, to transform wild-type P. pantotrophus DSM 2944 into a proficient SynBio (Synthetic Biology) chassis. The initial findings highlight the antibiotic resistance profile of this prospective SynBio chassis. Subsequently, the best origin of replication (ori) was identified as RK2. In contrast, the non-replicative ori R6K was selected for the development of a suicide plasmid necessary for genome integration or gene deletion. Moreover, when assessing the most effective method for gene transfer, it was observed that conjugation had superior efficiency compared to electroporation, while transformation by heat shock was ineffective. Robust host fitness was demonstrated by stable plasmid maintenance, while standardized gene expression using an array of synthetic promoters could be shown. pEMG-based scarless gene deletion was successfully adapted, allowing gene deletion and integration. The successful integration of a gene cassette for terephthalic acid degradation is showcased. The resulting strain can grow on both monomers of polyethylene terephthalate (PET), with an increased growth rate achieved through adaptive laboratory evolution.

CONCLUSION

The chassis roadmap for the development of P. pantotrophus DSM 2944 into a proficient SynBio chassis was implemented. The presented genetic toolkit allows genome editing and therewith the possibility to exploit Paracoccus for a myriad of applications.

Executive functions scale for university students: UEF-1

Introduction

Executive functions are a set of mental abilities that allow human beings to consciously regulate their behavior and, in a university setting, will have a significant impact on student success during professional training.

Objective

To develop a scale to assess executive functions in a university setting.

Method

Using a sample of 1,373 university students from Chile (663) and Ecuador (710) between 17 and 33 years old (M_age = 20.53, SD = 2.34). A study was carried out to analyze the psychometric properties of the instrument using a reliability and validity analysis for a scale that assesses executive functions: conscious monitoring of responsibilities, supervisory attentional system, conscious regulation of behavior, verification of behavior to learn, decision making, conscious regulation of emotions, and management of elements to solve tasks.

Results

Adequate internal consistency parameters were found between α = 0.71 and 0.85. The seven executive functions proposed on the scale correlated proportionally between r = 0.42 and 0.62. In the confirmatory factor analysis, good fit indices were obtained in the model of the seven executive functions x²₍₄₁₃₎ = 1649.14, p = <0.001, CFI = 0.91, SRMR = 0.04 and RMSEA = 0.04.

Discussion

The research carried out reaches its conclusion stating that the scale that was developed has the psychometric properties to assess executive functions in the Latin American setting. The results regarding previous research and the contribution made in the line of research of executive functions are discussed.