Exploring the transferability of large supramolecular assemblies to the vacuum-solid interface

We present an interplay of high-resolution scanning tunneling microscopy imaging and the corresponding theoretical calculations based on elastic scattering quantum chemistry techniques of the adsorption of a gold-functionalized rosette assembly and its building blocks on a Au(111) surface with the goal of exploring how to fabricate functional 3-D molecular nanostructures on surfaces. The supramolecular rosette assembly stabilized by multiple hydrogen bonds has been sublimed onto the Au(111) surface under ultra-high vacuum conditions; the resulting surface nanostructures are distinctly different from those formed by the individual molecular building blocks of the rosette assembly, suggesting that the assembly itself can be transferred intact to the surface by in situ thermal sublimation. This unanticipated result will open up new perspectives for growth of complex 3-D supramolecular nanostructures at the vacuum-solid interface

Reproducibility in the absence of selective reporting : An illustration from large-scale brain asymmetry research

Altres ajuts: Max Planck Society (Germany).The problem of poor reproducibility of scientific findings has received much attention over recent years, in a variety of fields including psychology and neuroscience. The problem has been partly attributed to publication bias and unwanted practices such as p-hacking. Low statistical power in individual studies is also understood to be an important factor. In a recent multisite collaborative study, we mapped brain anatomical left-right asymmetries for regional measures of surface area and cortical thickness, in 99 MRI datasets from around the world, for a total of over 17,000 participants. In the present study, we revisited these hemispheric effects from the perspective of reproducibility. Within each dataset, we considered that an effect had been reproduced when it matched the meta-analytic effect from the 98 other datasets, in terms of effect direction and significance threshold. In this sense, the results within each dataset were viewed as coming from separate studies in an "ideal publishing environment," that is, free from selective reporting and p hacking. We found an average reproducibility rate of 63.2% (SD = 22.9%, min = 22.2%, max = 97.0%). As expected, reproducibility was higher for larger effects and in larger datasets. Reproducibility was not obviously related to the age of participants, scanner field strength, FreeSurfer software version, cortical regional measurement reliability, or regional size. These findings constitute an empirical illustration of reproducibility in the absence of publication bias or p hacking, when assessing realistic biological effects in heterogeneous neuroscience data, and given typically-used sample sizes

Determinants of penetrance and variable expressivity in monogenic metabolic conditions across 77,184 exomes

Hundreds of thousands of genetic variants have been reported to cause severe monogenic diseases, but the probability that a variant carrier develops the disease (termed penetrance) is unknown for virtually all of them. Additionally, the clinical utility of common polygenetic variation remains uncertain. Using exome sequencing from 77,184 adult individuals (38,618 multi-ancestral individuals from a type 2 diabetes case-control study and 38,566 participants from the UK Biobank, for whom genotype array data were also available), we apply clinical standard-of-care gene variant curation for eight monogenic metabolic conditions. Rare variants causing monogenic diabetes and dyslipidemias display effect sizes significantly larger than the top 1% of the corresponding polygenic scores. Nevertheless, penetrance estimates for monogenic variant carriers average 60% or lower for most conditions. We assess epidemiologic and genetic factors contributing to risk prediction in monogenic variant carriers, demonstrating that inclusion of polygenic variation significantly improves biomarker estimation for two monogenic dyslipidemias

Una experiencia de analíticas de aprendizaje utilizando tableros de visualización de interacciones como soporte a la tutoría virtual

We live in the digital age of data, and the technologies we use allow us to store different records that can serve as inputs for decision making in any learning environment. This work was developed in a virtual university context, applying learning analytics based on interaction visualization boards. The study was based on the question: how to support tutoring in a virtual course through the use of visualization boards ofstudent activity? The research method used was formulated under a quasi-experimental cross-sectional design, with a mixed approach, developed through an introductory course on mobile technologies and virtual platforms for learning. The study involved 55 students who had no previous experience of training in virtual environments. The total number of participants was divided into groups and moderated by 5 virtual tutors at the beginner level. The results present an experience of Learning Analytics (LA) using visualization dashboards to support the work of the virtual tutor, highlighting that through graphics, it is easier to identify the most active students within a group, verify access to tasks and URL resources, visualize the number 2 of submissions of an activity, establish percentages of dedication, evaluate performance through qualifications and intervene in a didactic and pedagogical way when necessary

Volumetric power input as a reliable parameter for scale-up from shake flask to stirred-tank bioreactor: Production of a recombinant glycoprotein by Streptomyces lividans

The filamentous morphology of Streptomyces lividans depends on the culture conditions, affecting the production, secretion and post-translational modifications of recombinant glycoproteins. In this work, the previously reported volumetric power input (P/V) in conventional (NF) and coiled (CF) shake flasks were scaled-up to a stirred bioreactor. The effects on the growth and morphology of S. lividans were analyzed, as well as, the production and O-mannosylation of the recombinant APA glycoprotein from Mycobacterium tuberculosis. Specific growth rates of 5. lividans and similar recombinant glycoprotein (rAPA) yields were observed between NF and bioreactor cultures. In addition, we have found up to seven mannose residues attached to the C-terminal of the rAPA in bioreactor cultures, one more than in NF and CF. However, at similar P/V values, morphological and kinetic differences were found. Our data indicate that P/V as scale-up criteria in the production of recombinant glycoproteins in S. lividans can be successful in some, but not all the kinetic and stoichiometric parameters, suggesting that the metabolic cell responses can be affected by aeration/hydrodynamics between bioreactor and shake flasks. © 2019, Universidad Autonoma Metropolitana Iztapalapa. All rights reserved

Volumetric power input as a reliable parameter for scale-up from shake flask to stirred-tank bioreactor: Production of a recombinant glycoprotein by Streptomyces lividans

The filamentous morphology of Streptomyces lividans depends on the culture conditions, affecting the production, secretion and post-translational modifications of recombinant glycoproteins. In this work, the previously reported volumetric power input (P/V) in conventional (NF) and coiled (CF) shake flasks were scaled-up to a stirred bioreactor. The effects on the growth and morphology of S. lividans were analyzed, as well as, the production and O-mannosylation of the recombinant APA glycoprotein from Mycobacterium tuberculosis. Specific growth rates of 5. lividans and similar recombinant glycoprotein (rAPA) yields were observed between NF and bioreactor cultures. In addition, we have found up to seven mannose residues attached to the C-terminal of the rAPA in bioreactor cultures, one more than in NF and CF. However, at similar P/V values, morphological and kinetic differences were found. Our data indicate that P/V as scale-up criteria in the production of recombinant glycoproteins in S. lividans can be successful in some, but not all the kinetic and stoichiometric parameters, suggesting that the metabolic cell responses can be affected by aeration/hydrodynamics between bioreactor and shake flasks. © 2019, Universidad Autonoma Metropolitana Iztapalapa. All rights reserved

L-Proline as an efficient and reusable promoter for the synthesis of coumarins in ionic liquid

The effect of L-proline as a promoter on the condensation reaction of salicylaldehyde or its derivatives with ethyl acetoacetate in neutral ionic liquid [emim]BF4 was studied. All reactions were carried out under mild reaction conditions and achieved high yields. Moreover, the ionic liquid containing L-proline could be recycled and reused for several times without noticeably decreasing in productivity. The results show that the L-proline-[emim]BF4 system has a potential in contribution to the development of environmentally friendly and inexpensive processes in organic syntheses