Hybrid flexible (HyFlex) seminar delivery – A technical overview of the implementation

This paper investigates a new technology for Hybrid flexible delivery (known as HyFlex), as implemented at King's College London. The relatively novel character of HyFlex, of mixing synchronously on-line and in-room teaching, and the recent changes due to the COVID-19 pandemic mean this use of the technology and teaching model is largely new to the UK. This research evaluated audio quality in the context of a HyFlex technical environment. The paper provides a high-level overview of the process of designing a HyFlex solution and presents a detailed evaluation of the impact of reverberation in relation to the accuracy of automatically generated subtitles and the influence of microphone selection. The paper shows that there was a significant relationship between the reverberation, the audio quality, and the subtitling system, which is important as past studies highlighted audio quality is key for the students' experience. It presents a viable and simple methodology to estimate the audio quality on installed HyFlex systems to improve the students experience in a hybrid teaching environment

L1CAM binds ErbB receptors through Ig-like domains coupling cell adhesion and neuregulin signalling.

During nervous system development different cell-to-cell communication mechanisms operate in parallel guiding migrating neurons and growing axons to generate complex arrays of neural circuits. How such a system works in coordination is not well understood. Cross-regulatory interactions between different signalling pathways and redundancy between them can increase precision and fidelity of guidance systems. Immunoglobulin superfamily proteins of the NCAM and L1 families couple specific substrate recognition and cell adhesion with the activation of receptor tyrosine kinases. Thus it has been shown that L1CAM-mediated cell adhesion promotes the activation of the EGFR (erbB1) from Drosophila to humans. Here we explore the specificity of the molecular interaction between L1CAM and the erbB receptor family. We show that L1CAM binds physically erbB receptors in both heterologous systems and the mammalian developing brain. Different Ig-like domains located in the extracellular part of L1CAM can support this interaction. Interestingly, binding of L1CAM to erbB enhances its response to neuregulins. During development this may synergize with the activation of erbB receptors through L1CAM homophilic interactions, conferring diffusible neuregulins specificity for cells or axons that interact with the substrate through L1CAM

Topological distribution of reversible and non reversible degradation in perovskite solar cells

Lead halide perovskites have recently raised as an easy to process and cost effective photovoltaic material. However, stability issues have to be addressed to meet the market need for 25 years durable technology. The stability of the perovskite itself, as well as the stability of the perovskite embedded in a complete device under real working conditions, are a key challenge for perovskite solar cells. Within this study, we used Photoconductive Atomic Force Microscopy pcAFM and Photoluminescence imaging PL to investigate at the nanoscale level the degradation of the perovskite film under light and voltage stress. Then, we correlate the nanoscale pcAFM and PL analysis to the macroscopic device behaviour in similar ageing condition. We found that non reversible performance losses in a complete device originate from degradation localised at the grain boundaries of the perovskite film. Interesting, within the bulk of the perovskite grains we observed fully reversible behaviours. We conclude that the grain boundaries are detrimental to the device stability and they need to be minimized or passivated to achieve fully stable perovskite solar cells even under anhydrous condition

Estrogenic activity, race/ethnicity, and Indigenous American ancestry among San Francisco Bay Area women.

Estrogens play a significant role in breast cancer development and are not only produced endogenously, but are also mimicked by estrogen-like compounds from environmental exposures. We evaluated associations between estrogenic (E) activity, demographic factors and breast cancer risk factors in Non-Latina Black (NLB), Non-Latina White (NLW), and Latina women. We examined the association between E activity and Indigenous American (IA) ancestry in Latina women. Total E activity was measured with a bioassay in plasma samples of 503 women who served as controls in the San Francisco Bay Area Breast Cancer Study. In the univariate model that included all women with race/ethnicity as the independent predictor, Latinas had 13% lower E activity (p = 0.239) and NLBs had 35% higher activity (p = 0.04) compared to NLWs. In the multivariable model that adjusted for demographic factors, Latinas continued to show lower E activity levels (26%, p = 0.026), but the difference between NLBs and NLWs was no longer statistically significant (p = 0.431). An inverse association was observed between E activity and IA ancestry among Latina women (50% lower in 0% vs. 100% European ancestry, p = 0.027) consistent with our previously reported association between IA ancestry and breast cancer risk. These findings suggest that endogenous estrogens and exogenous estrogen-like compounds that act on the estrogen receptor and modulate E activity may partially explain racial/ethnic differences in breast cancer risk

EDROOM: a free tool for the UML2 component based design and automatic code generation of tiny embedded real time system

International audienceThe use of tiny real time kernels to develop embedded systems is broadly extended. They offer basic services with small overhead footprints in the final product. Usually, these kind of kernels are compliant with the POSIX 1003.13 specification. The use of graphical modelling and automatic code generation tools for developing these kind of small software embedded system if often not considered for several reasons: they are expensive, the learning curve to obtain benefits is often large and finally the generated code usually does not fit well with the platform or exceed the desired size. In this paper we present the adaptation of a free tool, known as EDROOM, to develop this kind of real time software system. EDROOM is inspired on the ROOM modelling language and provides graphical modelling and automatic Embedded C++ code generation. EDROOM is compliant with the new UML2 graphical notation for component based system design and hierarchical behaviour. The new version of EDROOM is a cross development multiplatform generation tool and includes facilities for static control of all resources in order to completely avoid the use of dynamic memory. Our tool has been used in the software development of a small satellite (NANOSAT-01) which is fully functional nowadays. The tool is free distributed in conjunction with a group of code test bench that can be used to validate any port to another architecture

Manual de Procedimientos administrativos e Indicadores de Gestión

Manual of administrative procedures of the Center of Libraries of the University of Caldas (Manizales, Colombia). Includes several indicators of management as guide for the managers of the dependence

Enzyme-Directed Mutasynthesis: A Combined Experimental and Theoretical Approach to Substrate Recognition of a Polyketide Synthase

Acyltransferase domains control the extender unit recognition in Polyketide Synthases (PKS) and thereby the side-chain diversity of the resulting natural products. The enzyme engineering strategy presented here allows the alteration of the acyltransferase substrate profile to enable an engineered biosynthesis of natural product derivatives through the incorporation of a synthetic malonic acid thioester. Experimental sequence−function correlations combined with computational modeling revealed the origins of substrate recognition in these PKS domains and enabled a targeted mutagenesis. We show how a single point mutation was able to direct the incorporation of a malonic acid building block with a non-native functional group into erythromycin. This approach, introduced here as enzyme-directed mutasynthesis, opens a new field of possibilities beyond the state of the art for the combination of organic chemistry and biosynthesis toward natural product analogues