179 research outputs found
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An ECOOP web portal for visualising and comparing distributed coastal oceanography model and in situ data
As part of a large European coastal operational oceanography project (ECOOP), we have developed a web portal for the display and comparison of model and in situ marine data. The distributed model and in situ datasets are accessed via an Open Geospatial Consortium Web Map Service (WMS) and Web Feature Service (WFS) respectively. These services were developed independently and readily integrated for the purposes of the ECOOP project, illustrating the ease of interoperability resulting from adherence to international standards. The key feature of the portal is the ability to display co-plotted timeseries of the in situ and model data and the quantification of misfits between the two. By using standards-based web technology we allow the user to quickly and easily explore over twenty model data feeds and compare these with dozens of in situ data feeds without being concerned with the low level details of differing file formats or the physical location of the data. Scientific and operational benefits to this work include model validation, quality control of observations, data assimilation and decision support in near real time. In these areas it is essential to be able to bring different data streams together from often disparate locations
Observing and modelling phytoplankton community structure in the North Sea
© Author(s) 2017. CC Attribution 3.0 License. Phytoplankton form the base of the marine food chain, and knowledge of phytoplankton community structure is fundamental when assessing marine biodiversity. Policy makers and other users require information on marine biodiversity and other aspects of the marine environment for the North Sea, a highly productive European shelf sea. This information must come from a combination of observations and models, but currently the coastal ocean is greatly under-sampled for phytoplankton data, and outputs of phytoplankton community structure from models are therefore not yet frequently validated. This study presents a novel set of in situ observations of phytoplankton community structure for the North Sea using accessory pigment analysis. The observations allow a good understanding of the patterns of surface phytoplankton biomass and community structure in the North Sea for the observed months of August 2010 and 2011. Two physical-biogeochemical ocean models, the biogeochemical components of which are different variants of the widely used European Regional Seas Ecosystem Model (ERSEM), were then validated against these and other observations. Both models were a good match for sea surface temperature observations, and a reasonable match for remotely sensed ocean colour observations. However, the two models displayed very different phytoplankton community structures, with one better matching the in situ observations than the other. Nonetheless, both models shared some similarities with the observations in terms of spatial features and inter-annual variability. An initial comparison of the formulations and parameterizations of the two models suggests that diversity between the parameter settings of model phytoplankton functional types, along with formulations which promote a greater sensitivity to changes in light and nutrients, is key to capturing the observed phytoplankton community structure. These findings will help inform future model development, which should be coupled with detailed validation studies, in order to help facilitate the wider application of marine biogeochemical modelling to user and policy needs
Utility aspects of sugarcane bagasse as a feedstock for bioethanol production: leading role of steam explosion as a pretreatment technique
Lignocellulosic biomass is a powerful approach to produce sustainable biofuels and the further achievement of the goal of biomass conversion into a second-generation clean energy that can cope with the depletion of fossil reserves and rising energy requirements. In the conversion process, a pretreatment is essential to overcome the recalcitrance of the lignocellulosic biomass; accelerate its disintegration into cellulose, hemicellulose, and lignin; and, in turn, obtain an optimal yield of fermentable sugars in the enzymatic hydrolysis. In addition to this, it should be industrially scalable and capable of enhancing fuel properties and feedstock processability. Here, steam explosion technology has stood out due to its results and advantages, such as wide applicability, high efficiency in the short term, or lack of contamination despite its conventionality. This gentle and fast pretreatment incorporates high temperature autohydrolysis and structural alteration by explosive decompression. The steam explosion method has been one of the most effectual, especially for the hydrolysis of cellulose from agricultural wastes due to the lower quantity of acetyl groups in the composition of hemicellulose. In this aspect, sugarcane bagasse is a promising feedstock for bioethanol production due to its high cellulosic content and elevated availability. The objective of this review has been to compile the latest information on steam explosion pretreatment, stages, equipment, variables involved, by-products generated, as well as the advantages and disadvantages of the technique. At the same time, its feasibility and viability using sugarcane bagasse as feedstock has been discussed. Finally, the effectiveness of the technique with different feedstocks has been evaluated.Xunta de Galicia | Ref. ED431F 2020/12Agencia Estatal de Investigación | Ref. RYC-2017-22891Xunta de Galicia | Ref. ED481B-2019/09
Assessment of metals bound to marine plankton proteins and to dissolved proteins in seawater
Studies based on laser ablation–inductively coupled plasma-mass spectrometry (LA–ICP-MS) have been performed to assess metal bound to dissolved proteins and proteins from marine plankton after two-dimensional polyacrylamide gel electrophoresis (2D PAGE). Dissolved proteins were pre-concentrated from surface seawater (60 L) by tangential ultrafiltration with 10 kDa molecular weight cut-off (MWCO) membranes and further centrifugal ultrafiltration (10 kDa) before proteins isolation by methanol/chloroform/water precipitation. Proteins isolation from plankton was assessed after different trichloroacetic acid (TCA)/acetone and methanol washing stages, and further proteins extraction with a phenol solution. LA–ICP-MS analysis of the electrophoretic profiles obtained for dissolved proteins shows the presence of Cd, Cr, Cu, and Zn in five spots analyzed. These proteins exhibit quite similar molecular weights (within the 10–14 kDa range) and pIs (from 5.8 to 7.3). Cd, Cr, Cu, and Zn have also been found to be associated to proteins isolated from plankton samples. In this case, Cd has been found to be bound to proteins of quite different molecular weight (9, 13 and 22 kDa) and pIs (4.5, 5.2, 5.5, and 10). However, trace elements such as Cr, Cu and Zn appear to be mainly bound to plankton proteins of low molecular weight and variable pI
Impact of the COVID-19 pandemic on hepatitis B and C elimination: An EASL survey
Hepatitis B virus; Hepatitis C virus; COVID-19 pandemicVirus de la hepatitis B; Virus de la hepatitis C; Pandemia de COVID-19Virus de l'hepatitis B; Virus de l'hepatitis C; Pandèmia del COVID-19Background & Aims
The World Health Organization (WHO) HBV and HCV elimination targets, set in 2016 and based on projections to 2030, were unable to consider the impact of intervening factors. To evaluate the impact of the COVID-19 pandemic on viral hepatitis elimination programs, the European Association for the Study of the Liver (EASL) conducted a survey in liver centers worldwide in 2021.
Methods
A web-based questionnaire was distributed (May-July 2021) to all EASL members representing clinical units providing HBV and HCV hepatitis care. Results are expressed as absolute numbers and reduction rates for each care activity.
Results
Data were collected from 32 European and 12 non-European clinical centers. Between January 2019 (pre-pandemic) and December 2020 (during the pandemic), chronic HBV consultations decreased by 32% and 26%, new referrals by 38% and 39%, HBV testing rates by 39% and 21% (for HBsAg detection) and 30% and 22% (for HBV DNA detection), and new HBV treatments by 20% and 44% (p = 0.328) in European and non-European centers, respectively. With regard to HCV during the same time frame, the overall reductions were 39% and 50% for consultations, 49% and 49% for new referrals, 11% and 38% for HCV RNA detection, and 51% and 54% for new HCV antiviral treatments for European and non-European Centers, respectively (p = 0.071).
Conclusions
All steps in the viral hepatitis care cascade have been hampered by the COVID-19 pandemic, with a comparable impact across different centers. These data reaffirm the pandemic’s major effect on global viral hepatitis elimination programs and suggest that actions to achieve the WHO 2030 targets should be reconsidered and revised to account for each country's progress relative to pre-pandemic values
Effect of Hepatitis E Virus RNA Universal Blood Donor Screening, Catalonia, Spain, 2017-2020
Altres ajuts: Banc de Sang i Teixits.Hepatitis E virus (HEV) is the major cause of acute viral hepatitis in several countries in Europe. HEV is acquired mainly by consumption of contaminated pork but can also be transmitted through blood transfusion. HEV infection is usually self-limited but can become persistent in immunocompromised persons. During the fi rst 30 months of HEV RNA universal screening of blood donations in Catalonia, Spain, we identifi ed 151 HEV RNA-positive donations (1/4,341 blood donations). Most infected donors reported consumption of pates and sausages, and 58% were negative for HEV IgM and IgG. All HEV isolates belonged to genotype 3. All infected donors spontaneously resolved the infection, and no neurologic symptoms and reinfections were observed after 1 year of follow-up. Since the implementation of HEV RNA universal screening, no new cases of transfusion-transmitted HEV infection were reported. Our data indicate HEV screening of blood donations provides safer blood for all recipients, especially for immunosuppressed persons
Zoonotic abbreviata caucasica in wild chimpanzees (Pan troglodytes verus) from Senegal
Abbreviata caucasica (syn. Physaloptera mordens) has been reported in human and various non-human primates including great apes. The identification of this nematode is seldom performed and relies on egg characterization at the coproscopy, in the absence of any molecular tool. Following the recovery of two adult females of A. caucasica from the feces of wild Senegalese chimpanzees, morphometric characteristics were reported and new data on the width of the esophagus (0.268– 0.287 mm) and on the cuticle structure (0.70–0.122 mm) were provided. The molecular characterization of a set of mitochondrial (cox1, 16S rRNA, 12S rRNA) and nuclear (18S rRNA and ITS2) partial genes was performed. Our phylogenetic analysis indicates for the first time that A. caucasica is monophyletic with Physaloptera species. A novel molecular tool was developed for the routine diagnosis of A. caucasica and the surveillance of Nematoda infestations. An A. caucasica-specific qPCR targeting the 12S gene was assessed. The assay was able to detect up to 1.13 × 10−3 eggs/g of fecal matter irrespective of its consistency, with an efficiency of 101.8% and a perfect adjustment (R2 = 0.99). The infection rate by A. caucasica in the chimpanzee fecal samples was 52.08%. Only 6.19% of the environmental samples were positive for nematode DNA and any for A. caucasica. Our findings indicate the need for further studies to clarify the epidemiology, circulation, life cycle, and possible pathological effects of this infestation using the molecular tool herein developed
Incidents control in radiotherapy oncology
Primer pla de l'escut del monarca del s. XVI,
conservat i ubicat a la porta de la UB. Mesura
1,60 x 2,20 metre si és de pedra sorrenca
Analysis of the oscillations induced by a supersonic jet applied to produce nanofibers
Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGHigh-performance fibers are key components for enhancing the mechanical properties of composite materials. The development of high strength nanofibers augurs the production of new nano-composites with outstanding features. However, the robust production of continuous glass nanofibers that can be feasible processed for efficiently manufacturing nanocomposites is still challenging. Recently, Cofiblas (Continuous Fiberizing by Laser melting and Supersonic dragging) was demonstrated as a technique capable of producing continuous glass nanofibers with unlimited length. Cofiblas process has some similarities with the widely known melt blowing technique for the production of polymeric fibers. In both techniques, the design of the gas nozzle is key to ensure the feasibility of the process since the turbulences of the gas jet may induce strong whipping of the filament. This paper gives novel experimental evidences on the correlation of the supersonic gas jet instabilities with the oscillation of the filament in the melt-blowing and Cofiblas processes, relating these oscillations with the presence of shock waves and unsteadiness in the flow, and gives valuable insight into the use of supersonic jets in the melt blowing process as an effective approach for the formation of nanofibers. A thin 3D-axisymmetric model in OpenFOAM® was put to test by comparing the performance of different solvers which were validated by flow visualization of the exit jet using digital holography (DH). In order to perform a realistic and thorough validation, we simulated the optical measurements of the flow from the CFD simulations of the mass density by Abel transform and numerical differentiation. The application of digital holography as the flow visualization technique makes possible both a precise validation of the density maps obtained from the Abel transformation of the 2D-alike results, and the analysis of the shockwave pattern in the air jet. Conversely, the numerical reconstruction of time-averaged holograms is employed to detect unsteadiness in the flow and to analyze the fiber oscillation, which is essential to assess the stability of the process. Lastly, the analysis and comparison of the vibration of the filament using the basic design and the optimized nozzle demonstrates a clear influence of the shock waves and flow unsteadiness in the stability of the filament.Agencia Estatal de Investigación | Ref. PGC2018-094900-B-I00Xunta de Galicia | Ref. ED431C 2019/23Ministerio de Universidades | Ref. FPU20/0311
Quantifying causal teleconnections to drought and fire risks in Indonesian Borneo
This is the final version. Available on open access from Wiley via the DOI in this recordData availability statement: Datasets for this research are openly available in the in-text citations. For observational estimates (ERA5, CHIRPS, Hadley SST, etc.), readers are referred to Tables S1 and S2 for details. Climate model data used in this study are available from the CMIP6 archive at https://esgf-index1.ceda.ac.uk/search/cmip6-ceda/Fires occurring over the peatlands in Indonesian Borneo accompanied by droughts have posed devastating impacts on human health, livelihoods, economy and the natural environment, and their prevention requires comprehensive understanding of climate-associated risk. Although it is widely known that the droughts are associated with El Niño events, the onset process of El Niño and thus the drought precursors and their possible changes under the future climate are not clearly understood. Here, we use a causal network approach to quantify the strength of teleconnections to droughts at a seasonal timescale shown in observations and climate models. We portray two drivers of June-July-August (JJA) droughts identified through literature review and causal analysis, namely Niño 3.4 sea surface temperature (SST) in JJA (El Niño Southern Oscillation [abbreviated as ENSO]) and SST anomaly over the eastern North Pacific to the east of the Hawaiian Islands (abbreviated as Pacific SST) in March-April-May (MAM) period. We argue that the droughts are strongly linked to ENSO variability, with drier years corresponding to El Niño conditions. The droughts can be predicted with a lead time of 3 months based on their associations with Pacific SST, with higher SST preceding drier conditions. We find that under the SSP585 scenario, the Coupled Model Intercomparison Phase 6 (CMIP6) multi-model ensembles show significant increase in both the maximum number of consecutive dry days in the Indonesian Borneo region in JJA (p = 0.006) and its linear association with Pacific SST in MAM (p = 0.001) from year 2061 to 2100 compared with the historical baseline. Some models are showing unrealistic amounts of JJA rainfall and underestimate drought risks in Indonesian Borneo and their teleconnections, owing to the underestimation of ENSO amplitude and overestimation of local convections. Our study strengthens the possibility of early warning triggers of fires and stresses the need for taking enhanced climate risk into consideration when formulating long-term policies to eliminate fires.Engineering and Physical Sciences Research Council (EPSRC
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