Analysis of 2D airglow imager data with respect to dynamics using machine learning

We demonstrate how machine learning can be easily applied to support the analysis of large quantities of excited hydroxyl (OH*) airglow imager data. We use a TCN (temporal convolutional network) classification algorithm to automatically pre-sort images into the three categories “dynamic” (images where small-scale motions like turbulence are likely to be found), “calm” (clear-sky images with weak airglow variations) and “cloudy” (cloudy images where no airglow analyses can be performed). The proposed approach is demonstrated using image data of FAIM 3 (Fast Airglow IMager), acquired at Oberpfaffenhofen, Germany, between 11 June 2019 and 25 February 2020, achieving a mean average precision of 0.82 in image classification. The attached video sequence demonstrates the classification abilities of the learned TCN. Within the dynamic category, we find a subset of 13 episodes of image series showing turbulence. As FAIM 3 exhibits a high spatial (23 m per pixel) and temporal (2.8 s per image) resolution, turbulence parameters can be derived to estimate the energy diffusion rate. Similarly to the results the authors found for another FAIM station (Sedlak et al., 2021), the values of the energy dissipation rate range from 0.03 to 3.18 W kg−1.</p

Evaluation of antimicrobial effectiveness of pimaricin-loaded thermosensitive nanohydrogels in grape juice

Pimaricin-loaded poly(N-isopropylacrylamide) nanohydrogels with and without acrylic acid, were evaluated as food-spoilage inhibitors in a model system and a real food product: grape juice. Pimaricin was proposed as a non-allergenic alternative to sulphites for protecting juices against recontamination. However, pimaricin may degrade under conditions and treatments (heating, acidification, lighting) commonly applied in producing fresh juices. Nanohydrogel encapsulation may be a feasible procedure to avoid pimaricin degradation, improving its antimicrobial activity. Pimaricin-free nanohydrogels did not affect the growth of the indicator yeast either in the food model system or in grape juice. Conversely, pimaricin-loaded nanohydrogels effectively inhibited the growth of the indicator yeast. In some cases, the inhibition was extended even further than using free pimaricin. For instance, in the food model system, pimaricin-loaded nanohydrogels with acrylic acid (NPPNIPA-20AA(5)) prevented the yeast growth for more than 81 h while free pimaricin was only effective for 12 h. Despite pimaricin-loaded nanohydrogels without acrylic acid (NPPNIPA(5)) were able to reduce maximum yeast growth, as in all treatments with pimaricin, the extent of the inhibitory effect was not significantly (p>0.05) different to that achieved with free pimaricin. In grape juice, both free pimaricin and NPPNIPA-20AA(5) treatment completely inhibited the growth of the indicator yeast until the end of the bioassay. However, the latter provided similar inhibition levels using a smaller amount of pimaricin due to PNIPA-20AA(5) protection and its controlled release from the nanohydrogel. Therefore, nanohydrogel encapsulation may help to optimise antifungal treatments and decrease the incidence of food allergies.Funded by grant (MAT 2006-11662-CO3-CO2-C01/MAT 2010-21509-C03-01/EUI 2008-00115) from the “Ministerio de Educación y Ciencia” (Spain). Grant (SFRH/BPD/87910/2012) from the Fundação para a Ciência e Tecnologia (FCT, Portugal). Marie Curie COFUND Postdoctoral Research Fellow

Heterochronic Shift in Hox-Mediated Activation of Sonic hedgehog Leads to Morphological Changes during Fin Development

We explored the molecular mechanisms of morphological transformations of vertebrate paired fin/limb evolution by comparative gene expression profiling and functional analyses. In this study, we focused on the temporal differences of the onset of Sonic hedgehog (Shh) expression in paired appendages among different vertebrates. In limb buds of chick and mouse, Shh expression is activated as soon as there is a morphological bud, concomitant with Hoxd10 expression. In dogfish (Scyliorhinus canicula), however, we found that Shh was transcribed late in fin development, concomitant with Hoxd13 expression. We utilized zebrafish as a model to determine whether quantitative changes in hox expression alter the timing of shh expression in pectoral fins of zebrafish embryos. We found that the temporal shift of Shh activity altered the size of endoskeletal elements in paired fins of zebrafish and dogfish. Thus, a threshold level of hox expression determines the onset of shh expression, and the subsequent heterochronic shift of Shh activity can affect the size of the fin endoskeleton. This process may have facilitated major morphological changes in paired appendages during vertebrate limb evolution

Point Mutations in GLI3 Lead to Misregulation of its Subcellular Localization

Background Mutations in the transcription factor GLI3, a downstream target of Sonic Hedgehog (SHH) signaling, are responsible for the development of malformation syndromes such as Greig-cephalopolysyndactyly-syndrome (GCPS), or Pallister-Hall-syndrome (PHS). Mutations that lead to loss of function of the protein and to haploinsufficiency cause GCPS, while truncating mutations that result in constitutive repressor function of GLI3 lead to PHS. As an exception, some point mutations in the C-terminal part of GLI3 observed in GCPS patients have so far not been linked to loss of function. We have shown recently that protein phosphatase 2A (PP2A) regulates the nuclear localization and transcriptional activity a of GLI3 function. Principal Findings We have shown recently that protein phosphatase 2A (PP2A) and the ubiquitin ligase MID1 regulate the nuclear localization and transcriptional activity of GLI3. Here we show mapping of the functional interaction between the MID1-α4-PP2A complex and GLI3 to a region between amino acid 568-1100 of GLI3. Furthermore we demonstrate that GCPS-associated point mutations, that are located in that region, lead to misregulation of the nuclear GLI3-localization and transcriptional activity. GLI3 phosphorylation itself however appears independent of its localization and remains untouched by either of the point mutations and by PP2A-activity, which suggests involvement of an as yet unknown GLI3 interaction partner, the phosphorylation status of which is regulated by PP2A activity, in the control of GLI3 subcellular localization and activity. Conclusions The present findings provide an explanation for the pathogenesis of GCPS in patients carrying C-terminal point mutations, and close the gap in our understanding of how GLI3-genotypes give rise to particular phenotypes. Furthermore, they provide a molecular explanation for the phenotypic overlap between Opitz syndrome patients with dysregulated PP2A-activity and syndromes caused by GLI3-mutations

The Epidemiology, Genetics and Future Management of Syndactyly

Syndactyly is a condition well documented in current literature due to it being the most common congenital hand defect, with a large aesthetic and functional significance