10 research outputs found
Automatic and visual reproducibility of perfusion and function measures for myocardial perfusion SPECT
Estimating aerodynamic roughness over complex surface terrain
Surface roughness plays a key role in determining aerodynamic roughness length (zo) and shear velocity, both of which are fundamental for determining wind erosion threshold and potential. While zo can be quantified from wind measurements, large proportions of wind erosion prone surfaces remain too remote for this to be a viable approach. Alternative approaches therefore seek to relate zo to morphological roughness metrics. However, dust-emitting landscapes typically consist of complex small-scale surface roughness patterns and few metrics exist for these surfaces which can be used to predict zo for modeling wind erosion potential. In this study terrestrial laser scanning was used to characterize the roughness of typical dust-emitting surfaces (playa and sandar) where element protrusion heights ranged from 1 to 199âmm, over which vertical wind velocity profiles were collected to enable estimation of zo. Our data suggest that, although a reasonable relationship (R2â>â0.79) is apparent between 3-D roughness density and zo, the spacing of morphological elements is far less powerful in explaining variations in zo than metrics based on surface roughness height (R2â>â0.92). This finding is in juxtaposition to wind erosion models that assume the spacing of larger-scale isolated roughness elements is most important in determining zo. Rather, our data show that any metric based on element protrusion height has a higher likelihood of successfully predicting zo. This finding has important implications for the development of wind erosion and dust emission models that seek to predict the efficiency of aeolian processes in remote terrestrial and planetary environments
Guide dâutilisation de lâexĂ©cutable QrCodeGenerator
LâexĂ©cutable QrCodeGenrator permet la gĂ©nĂ©ration de codes de traçabilitĂ© et leur impression sur des Ă©tiquettes autocollantes.
LâexĂ©cutable est conçu pour rĂ©pondre en premier lieu au besoin Obsbio. A savoir un code de traçabilitĂ© unique faisant rĂ©fĂ©rence aux lignes de plan Imagine (https://doi.org/10.13155/86111).
Lâutilisation dâun code de traçabilitĂ© devient primordial dans la vie de la donnĂ©e et des Ă©chantillons biologiques. Cet outil sâinscrit totalement dans lâobjectif du projet SI MORSE (Marine Oganisms and Ressources and Storage systEm) dont lâobjectif est de tracer tous les Ă©chantillons biologiques non dĂ©truits (https://w3z.ifremer.fr/morse/ ).
Le code de traçabilitĂ© a pour objectif de tracer tous les Ă©chantillons depuis leur prĂ©lĂšvement, leur traitement, jusquâĂ leur archivage.
Ces actions viennent complĂ©ter les dispositifs dĂ©jĂ en place tel que lâutilisation du module workflow dans Labcollector pour le suivi des lots de piĂšces calcifiĂ©es (https://archimer.ifremer.fr/doc/00116/22764/)
Guide dâutilisation de lâinterface de saisie IMAGINE : Integration and MAnagement tool for bioloGical INdicEs
Ce document prĂ©sente pas Ă pas, les principales fonctionnalitĂ©s de saisie des donnĂ©es paramĂ©tres biologiques dans lâapplication Web IMAGINE : Integration and MAnagement tool for bioloGical INdicEs
Formaldehyde-fixation of platelets for flow cytometric measurement of phosphatidylserine exposure is feasible.
Strong platelet activation results in a redistribution of negatively charged phospholipids from the cytosolic to the outer leaflet of the cellular membrane. Annexin V has a high affinity to negatively charged phospholipids and can be used to identify procoagulant platelets. Formaldehyde fixation can cause factitious Annexin V binding. Our aim was to evaluate a method for fixing platelets avoiding additional Annexin V binding. We induced expression of negatively charged phospholipids on the surface of a fraction of platelets by combined activation with convulxin and thrombin in the presence of Annexin V-fluorescein isothiocyanate and calcium. Aliquots of resting and activated platelets were fixed with a low concentration, calcium-free formaldehyde solution. Both native platelets and fixed platelets were analyzed by flow cytometry immediately and after a 24-h storage at 4°C. We observed that the percentage of Annexin V positive resting platelets ranged from 1.5 to 9.3% for the native samples and from 0.4 to 12.8% for the fixed samples (P=0.706, paired t-test). The amount of Annexin V positive convulxin/thrombin activated platelets varied from 12.9 to 35.4% without fixation and from 15.3 to 36.3% after formalin fixation (P=0.450). After a 24-h storage at 4°C, Annexin V positive platelets significantly increased both in the resting and in the convulxin/thrombin activated samples of native platelets (both P<0.001), while results for formalin fixed platelets did not differ from baseline values (P=0.318 for resting fixed platelets; P=0.673 for activated fixed platelets). We conclude that platelet fixation with a low concentration, calcium-free formaldehyde solution does not alter the proportion of Annexin V positive platelets. This method can be used to investigate properties of procoagulant platelets by multicolor flow-cytometric analysis requiring fixation steps
Formaldehyde-fixation of platelets for flow cytometric measurement of phosphatidylserine exposure is feasible
Validation et exploration des données halieutiques dans l'application Valparaiso. Volet ObsBio
Ce document prĂ©sente pas Ă pas, les principales fonctionnalitĂ©s de validation et exploration des donnĂ©es paramĂ©tres biologiques dans lâapplication Web Valparaiso
Alzheimerâs disease: analysis of a mathematical model incorporating the role of prions
Sequential Cyk-4 binding to ECT2 and FIP3 regulates cleavage furrow ingression and abscission during cytokinesis
Cytokinesis is a highly regulated and dynamic event that involves the reorganization of the cytoskeleton and membrane compartments. Recently, FIP3 has been implicated in targeting of recycling endosomes to the mid-body of dividing cells and is found required for abscission. Here, we demonstrate that the centralspindlin component Cyk-4 is a FIP3-binding protein. Furthermore, we show that FIP3 binds to Cyk-4 at late telophase and that centralspindlin may be required for FIP3 recruitment to the mid-body. We have mapped the FIP3-binding region on Cyk-4 and show that it overlaps with the ECT2-binding domain. Finally, we demonstrate that FIP3 and ECT2 form mutually exclusive complexes with Cyk-4 and that dissociation of ECT2 from the mid-body at late telophase may be required for the recruitment of FIP3 and recycling endosomes to the cleavage furrow. Thus, we propose that centralspindlin complex not only regulates acto-myosin ring contraction but also endocytic vesicle transport to the cleavage furrow and it does so through sequential interactions with ECT2 and FIP3