A simple approach for synthesis, characterization and bioactivity of bovine bones to fabricate the polyurethane nanofiber containing hydroxyapatite nanoparticles

In the present study, we had introduced polyurethane (PU) nanofibers that contain hydroxyapatite (HAp) nanoparticles (NPs) as a result of an electrospinning process. A simple method that does not depend on additional foreign chemicals had been employed to synthesize HAp NPs through the calcination of bovine bones. Typically, a colloidal gel consisting of HAp/PU had been electrospun to form nanofibers. In this communication, physiochemical aspects of prepared nanofibers were characterized by FE-SEM, TEM and TEM-EDS, which confirmed that nanofibers were well-oriented and good dispersion of HAp NPs, over the prepared nanofibers. Parameters, affecting the utilization of the prepared nanofibers in various nano-biotechnological fields have been studied; for instance, the bioactivity of the produced nanofiber mats was investigated while incubating in simulated body fluid (SBF). The results from incubation of nanofibers, indicated that incorporation of HAp strongly activates the precipitation of the apatite-like particles, because of the HAp NPs act as seed, that accelerate crystallization of the biological HAp from the utilized SBF

DisProt: intrinsic protein disorder annotation in 2020

The Database of Protein Disorder (DisProt, URL: https://disprot.org) provides manually curated annotations of intrinsically disordered proteins from the literature. Here we report recent developments with DisProt (version 8), including the doubling of protein entries, a new disorder ontology, improvements of the annotation format and a completely new website. The website includes a redesigned graphical interface, a better search engine, a clearer API for programmatic access and a new annotation interface that integrates text mining technologies. The new entry format provides a greater flexibility, simplifies maintenance and allows the capture of more information from the literature. The new disorder ontology has been formalized and made interoperable by adopting the OWL format, as well as its structure and term definitions have been improved. The new annotation interface has made the curation process faster and more effective. We recently showed that new DisProt annotations can be effectively used to train and validate disorder predictors. We believe the growth of DisProt will accelerate, contributing to the improvement of function and disorder predictors and therefore to illuminate the ‘dark’ proteome

Caractérisation des périodes de sécheresse sur le domaine de l'Afrique simulée par le Modèle Régional Canadien du Climat (MRCC5)

Les conséquences des changements climatiques sur la fréquence ainsi que sur l'intensité des précipitations auront un impact direct sur les périodes de sécheresse et par conséquent sur différents secteurs économiques tels que le secteur de l'agriculture. Ainsi, dans cette étude, l'habilité du Modèle Régional Canadien du Climat (MRCC5) à simuler les différentes caractéristiques des périodes de sécheresse est évaluée pour 4 seuils de précipitation soit 0.5 mm, 1 mm, 2 mm et 3 mm. Ces caractéristiques incluent le nombre de jours secs, le nombre de périodes de sécheresse ainsi que le maximum de jours consécutifs sans précipitation associé à une récurrence de 5 ans. Les résultats sont présentés pour des moyennes annuelles et saisonnières. L'erreur de performance est évaluée en comparant le MRCC5 piloté par ERA-Interim aux données d'analyses du GPCP pour le climat présent (1997-2008). L'erreur due aux conditions aux frontières c'est-à-dire les erreurs de pilotage du MRCC5, soit par CanESM2 et par ERA-Interim ainsi que l'évaluation de la valeur ajoutée du MRCC5 face au CanESM2 sont également analysées. L'analyse de ces caractéristiques est également faite dans un contexte de climat changeant pour deux périodes futures, soit 2041-2070 et 2071-2100 à l'aide du MRCC5 piloté par le modèle de circulation générale CanESM2 de même que par le modèle CanESM2 sous le scénario RCP 4.5. Les résultats suggèrent que le MRCC5 piloté par ERA-Interim a tendance à surestimer la moyenne annuelle du nombre de jours secs ainsi que le maximum de jours consécutifs sans précipitation associé à une récurrence de 5 ans dans la plupart des régions de l'Afrique et une tendance à sous-estimer le nombre de périodes de sécheresse. En général, l'erreur de performance est plus importante que l'erreur due aux conditions aux frontières pour les différentes caractéristiques de périodes de sécheresse. Pour les régions équatoriales, les changements appréhendés par le MRCC5 piloté par CanESM2 pour les différentes caractéristiques de périodes de sécheresse et pour deux périodes futures (2041-2070 et 2071-2100), suggèrent une augmentation significatives du nombre de jours secs ainsi que du maximum de jours consécutifs sans précipitation associé à une récurrence de 5 ans. Une diminution significative du nombre de périodes de sécheresse est aussi prévue.\ud ______________________________________________________________________________ \ud MOTS-CLÉS DE L’AUTEUR : Modèle Régional du Climat, Changement climatique, Jours secs, Nombre de périodes de sécheresse, Événement de faible récurrence, Afriqu

Critical assessment of protein intrinsic disorder prediction

Abstract: Intrinsically disordered proteins, defying the traditional protein structure–function paradigm, are a challenge to study experimentally. Because a large part of our knowledge rests on computational predictions, it is crucial that their accuracy is high. The Critical Assessment of protein Intrinsic Disorder prediction (CAID) experiment was established as a community-based blind test to determine the state of the art in prediction of intrinsically disordered regions and the subset of residues involved in binding. A total of 43 methods were evaluated on a dataset of 646 proteins from DisProt. The best methods use deep learning techniques and notably outperform physicochemical methods. The top disorder predictor has Fmax = 0.483 on the full dataset and Fmax = 0.792 following filtering out of bona fide structured regions. Disordered binding regions remain hard to predict, with Fmax = 0.231. Interestingly, computing times among methods can vary by up to four orders of magnitude

EELS analysis of Nylon 6 nanofibers reinforced with nitroxide- functionalized graphene oxide

A detailed analysis by transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS) of nitroxide-functionalized graphene oxide layers (GOFT) dispersed in Nylon 6 nanofibers is reported herein. The functionalization and exfoliation process of graphite oxide to GOFT was confirmed by TEM using electron diffraction patterns (EDP), wherein 1-4 graphene layers of GOFT were observed. The distribution and alignment of GOFT layers within a sample of Nylon 6 nanofiber reveals that GOFT platelets are mainly within the fiber, but some were partially protruding from it. Furthermore, Nylon 6 nanofibers exhibited an average diameter of 225 nm with several microns in length. GOFT platelets embedded into the fiber, the pristine fiber, and amorphous carbon were analyzed by EELS where each spectra [corresponding to the carbon edge (C-K)] exhibited changes in the fine structure, allowing a clear distinction between: (i) GOFT single-layers, (ii) Nylon-6 nanofibers, and (iii) the carbon substrate. EELS analysis is presented here for the first time as a powerful tool to identify functionalized graphene single-layers (< 4 layers of GOFT) into a Nylon 6 nanofiber composite. � 2013 Elsevier Ltd. All rights reserved