22 research outputs found

    Validation of Envisat MERIS algorithms for chlorophyll retrieval in a large, turbid and optically-complex shallow lake

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    The 10-year archive of MEdium Resolution Imaging Spectrometer (MERIS) data is an invaluable resource for studies on lake system dynamics at regional and global scales. MERIS data are no longer actively acquired but their capacity for global scale monitoring of lakes from satellites will soon be re-established through the forthcoming Sentinel-3 Ocean and Land Colour Instrument (OLCI). The development and validation of in-water algorithms for the accurate retrieval of biogeochemical parameters is thus of key importance if the potential of MERIS and OLCI data is to be fully exploited for lake monitoring. This study presents the first extensive validation of algorithms for chlorophyll-a (chl-a) retrieval by MERIS in the highly turbid and productive waters of Lake Balaton, Hungary. Six algorithms for chl-a retrieval from MERIS over optically complex Case 2 waters, including band-difference and neural network architectures, were compared using the MERIS archive for 2007-2012. The algorithms were locally-tuned and validated using in situ chl-a data (n = 289) spanning the five year processed image time series and from all four lake basins. In general, both band-difference algorithms tested (Fluorescence Line Height (FLH) and Maximum Chlorophyll Index (MCI)) performed well, whereas the neural network processors were generally found to much less accurately retrieve in situ chl-a concentrations. The Level 1b FLH algorithm performed best overall in terms of chl-a retrieval (R2 = 0.87; RMSE = 4.19 mg m- 3; relative RMSE = 30.75%) and particularly at chl-a concentrations of ≥ 10 mg m- 3 (R2 = 0.85; RMSE = 4.81 mg m- 3; relative RMSE = 20.77%). However, under mesotrophic conditions (i.e., chl-a < 10 mg m- 3) FLH was outperformed by the locally-tuned FUB/WeW processor (relative FLH RMSE < 10 mg m- 3 = 57.57% versus relative FUB/WeW RMSE < 10 mg m- 3 = 46.96%). An ensemble selection of in-water algorithms is demonstrated to improve chl-a retrievals

    Peripartum Investigation of Red Blood Cell Properties in Women Diagnosed with Early-Onset Preeclampsia

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    We investigated peripartum maternal red blood cell (RBC) properties in early-onset preeclampsia (PE). Repeated blood samples were taken prospectively for hemorheological measurements at PE diagnosis (n = 13) or during 26–34 weeks of gestation in healthy pregnancies (n = 24), then at delivery, and 72 h postpartum. RBC aggregation was characterized by M index (infrared light transmission between the aggregated RBCs in stasis) and aggregation index (AI—laser backscattering from the RBC aggregates). We observed significantly elevated RBC aggregation (M index = 9.8 vs. 8.5; AI = 72.9% vs. 67.5%; p < 0.001) and reduced RBC deformability in PE (p < 0.05). A positive linear relationship was observed between AI and gestational age at birth in PE by regression analysis (R 2 = 0.554; p = 0.006). ROC analysis of AI showed an AUC of 0.84 (0.68–0.99) (p = 0.001) for PE and indicated a cutoff of 69.4% (sensitivity = 83.3%; specificity = 62.5%), while M values showed an AUC of 0.75 (0.58–0.92) (p = 0.019) and indicated a cutoff of 8.39 (sensitivity = 90.9% and specificity = 50%). The predicted probabilities from the combination of AI and M variables showed increased AUC = 0.90 (0.79–1.00) (p < 0.001). Our results established impaired microcirculation in early-onset PE manifesting as deteriorated maternal RBC properties. The longer the pathologic pregnancy persists, the more pronounced the maternal erythrocyte aggregation. AI and M index could help in the prognostication of early-onset PE, but further investigations are warranted to confirm the prognostic role before the onset of symptoms

    An Overview on Personal Protective Equipment (PPE) Fabricated with Additive Manufacturing Technologies in the Era of COVID-19 Pandemic

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    Different additive manufacturing technologies have proven effective and useful in remote medicine and emergency or disaster situations. The coronavirus disease 2019 (COVID-19) disease, caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) virus, has had a huge impact on our society, including in relation to the continuous supply of personal protective equipment (PPE). The aim of the study is to give a detailed overview of 3D-printed PPE devices and provide practical information regarding the manufacturing and further design process, as well as describing the potential risks of using them. Open-source models of a half-face mask, safety goggles, and a face-protecting shield are evaluated, considering production time, material usage, and cost. Estimations have been performed with fused filament fabrication (FFF) and selective laser sintering (SLS) technology, highlighting the material characteristics of polylactic acid (PLA), polyamide, and a two-compound silicone. Spectrophotometry measurements of transparent PMMA samples were performed to determine their functionality as goggles or face mask parts. All the tests were carried out before and after the tetra-acetyl-ethylene-diamine (TAED)-based disinfection process. The results show that the disinfection has no significant effect on the mechanical and structural stability of the used polymers; therefore, 3D-printed PPE is reusable. For each device, recommendations and possible means of development are explained. The files of the modified models are provided. SLS and FFF additive manufacturing technology can be useful tools in PPE development and small-series production, but open-source models must be used with special care

    Extracellular vesicles in blood, milk and body fluids of the female and male urogenital tract and with special regard to reproduction

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    Extracellular vesicles (EVs) are released from almost all cells and tissues. They are able to transport substances (e.g. proteins, RNA or DNA) at higher concentrations than in their environment and may adhere in a receptor- controlled manner to specific cells or tissues in order to release their content into the respective target structure. Blood contains high concentrations of EVs mainly derived from platelets, and, at a smaller amount, from erythrocytes. The female and male reproductive tracts produce EVs which may be associated with fertility or infertility and are released into body fluids and mucosas of the urogenital organs. In this review, the currently relevant detection methods are presented and critically compared. During pregnancy, placenta-derived EVs are dynamically detectable in peripheral blood with changing profiles depending upon progress of pregnancy and different pregnancy- associated pathologies, such as preeclampsia. EVs offer novel non-invasive diagnostic tools which may reflect the situation of the placenta and the fetus. EVs in urine have the potential of reflecting urogenital diseases including cancers of the neighbouring organs. Several methods for detection, quantification and phenotyping of EVs have been established, which include electron microscopy, flow cytometry, ELISA-like methods, Western blotting, and analyses based on Brownian motion. This review article summarises the current knowledge about EVs in blood and cord blood, in the different compartments of the male and female reproductive tract, in trophoblast cells from normal and pre-eclamptic pregnancies, in placenta ex vivo perfusate, in the amniotic fluid, and in breast milk, as well as their potential effects on natural killer (NK) cells as possible target

    The remote handling system of IFMIF-DONES

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    The International Fusion Materials Irradiation Facility-DEMO Oriented Neutron Source (IFMIF-DONES) consists of complex systems and massive components that need to be on site assembled and maintained. For several of them it is required to perform maintenance, inspection and monitoring tasks over many years in a hostile environment and in efficient, safe and reliable manner. The maintenance of IFMIF-DONES’ systems and components, located mainly in the Test Systems (TS), in the Lithium Systems (LS) and in the Accelerator Systems (AS), is classified as a Remote Handling (RH) Class 1st activity and as such is considered a crucial and essential activity whose success will strictly depend on the IFMIF-DONES RH capability. According to this, a Remote Handling System (RHS) for IFMIF-DONES, which comprises the whole set of Remote Handling Equipment and tooling for the execution of maintenance tasks, has been designed. A wide range of technologies is involved: special cranes, manipulator arms, lift interface frames, special cameras, control systems and virtual reality. In this paper an overview on status of the design of the main robotic systems and tooling of the RHS of IFMIF-DONES, including design requirements, functions and maintenance tasks to be performed, is given
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