In this work a constitutive relation for ice at high strain rates and an algorithm for its numerical integration are developed. This model is based on the Drucker–Prager plasticity criteria, which ...allows a different behavior in tension and in compression. In addition a failure criteria, based on pressure cut-offs, is implemented to describe the ice damage. In order to validate the constitutive model, numerical simulations were compared with experimental results, in which ice cylinders were impacted against a steel plate, allowing the measurement of the contact load. Three different numerical solvers are used in order to analyze its performance to appropriately modeling the ice behavior.
This paper presents and analyzes the behaviour of TRIP 1000 steel sheets subjected to low velocity perforation by conical projectiles. The relevance of this material resides in the potential ...transformation of retained
austenite to
martensite during impact loading. This process leads to an increase in strength and ductility of the material. However, this transformation takes place only under certain loading conditions strongly dependent on the initial temperature and deformation rate. In order to study the material behaviour under impact loading, perforation tests have been performed using a drop weight tower. Experiments were carried out at two different initial temperatures
T
0
=
213
K and
T
0
=
288
K, and within the range of impact velocities 2.5
m/s
⩽
V
0
⩽
4.5
m/s. The experimental setup enabled the measuring of impact velocity, residual velocity, load-time history and failure mode. In addition, dry and lubricated contacts between the striker and the plate have been investigated. Finally, by using X-ray diffraction it has been shown that no
martensitic transformation takes place during the perforation process. The causes involving the none-appearance of
martensite are examined.
Since the United Nations approved the eight Millennium Development Goals in 2000 and, 15 years later, the 2030 Agenda for Sustainable Development and its 17 Sustainable Development Goals (SDGs), the ...highest political institutions in the world have not stopped worrying about achieving the sustainability of the planet. Also in 2015, the European Commission prepared the European Union Action Plan for the Circular Economy, seeking a transition towards a less linear economy, in which products, materials, and resources are kept in the system for as long as possible and in which the generation of waste is minimized.
Since then, the European Union has continued issuing reports and communications to accelerate this process in search of a circular economy, making continuous references to the fact that, through circular economy initiatives, the SDGs would be fulfilled. In this context, the objectives of this paper are 1) to determine, through exploratory factor analysis and correlation analysis, whether there is a statistically significant relationship between circular economy initiatives undertaken in the EU and compliance with the SDGs; 2) to check, through a cluster analysis, if there are homogeneous groups of countries worldwide in terms of compliance with the SDGs; and 3) using this same technique, to check whether the countries that make up the EU achieve similar results in terms of compliance with the SDGs.
Pteronotus davyi, Davy's naked-backed bat, is a tropical bat whose current distribution in Mexico covers the watersheds of the Pacific and the Gulf coasts of Mexico, converges at the Isthmus of ...Tehuantepec, and continues into the Yucatan peninsula. We evaluated phylogeographic relationships among 18 populations in Mexico using data from the nucleotide sequence of the hypervariable II domain of the mitochondrial DNA control region from 105 specimens. Extant populations were distributed over 3 geographic regions (Pacific Coast, Gulf Coast, and Southeastern) that were delineated a priori according to floristic characteristics and biogeography. Coalescent simulations supported a phylogeographic model of 2 refugia situated in the south of Mexico (Arc and Soconusco refuges) during the late Pleistocene, followed by expansion into Pacific Coast, Gulf Coast, and Southeastern groups. The populations of the Southeast were genetically divergent from the Pacific and Gulf Coast populations, supporting the existence of 2 distinct lineages of P. davyi in Mexico, likely due to the Isthmus of Tehuantepec acting as a geographical barrier. Examination of our data revealed genetic differentiation of the Pacific and Gulf coastal groups but at a lower level relative to the Southeast. This pattern suggests that the Sierra Madre Occidental, Sierra Madre Oriental, and Sierra Madre del Sur act as physical barriers to dispersal for P. davyi.
There is increasing evidence that ferritin is a key marker of macrophage activation, but its potential role in influenza infection remains unexplored. Our aim was to assess whether hyperferritinaemia ...(ferritin ≥500 ng/mL) could be a marker of poor prognosis in hospitalized patients with confirmed influenza A infection.
We prospectively recruited all hospitalized adult patients who tested positive for the influenza A rRT-PCR assay performed on respiratory samples in two consecutive influenza periods (2016–17 and 2017–18). Poor outcome was defined as the presence of at least one of the following: respiratory failure, admission to the intensive care unit, or in-hospital mortality.
Among 494 patients, 68 (14%) developed poor outcomes; 112 patients (23%) had hyperferritinaemia (39/68, 57% in the poor-outcome group versus 73/426, 17% in the remaining patients, p < 0.0001). Median serum ferritin levels were significantly higher in the subgroup of patients with poor outcomes (609 ng/mL, range 231–967 versus 217 ng/mL, range 140–394, p < 0.0001). In multivariate analysis, hyperferritinaemia was associated with a five-fold increase in the odds ratio of developing poor outcome. After adjusting for classic influenza risk factors, ferritin remained as a significant predictive factor in all exploratory models. Ferritin levels had a good discriminative capacity with an area under the ROC curve of 0.72 (95% confidence interval (CI) 0.65–0.8, p < 0.001) and an overall diagnostic accuracy for predicting poor outcome of 79.3% (95%CI 75.4–82.7%).
Serum ferritin may discriminate a subgroup of patients with influenza infection who have a higher risk of developing a poor outcome.
Spray drying is a well-known operation to formulate food powders. Usually, the dryer performance is evaluated through trial and error given the complexity of transport phenomena. Regarding the ...microencapsulation of functional chia oil by spray drying, the main contribution of this study was to compare the accuracy of fundamental models for predicting the values of process variables (drying-air outlet temperature, Toutlet and feed flow rate, Vfeed) and powder properties (size, d32 and moisture content, H), under a wide range of drying conditions at laboratory (Büchi B-290) and pilot scales (Niro Production Minor). First, the coarse-scale approach modeled the dryer's chamber as a well-mixed reactor. The experimental values for Toutlet were: 72–109 °C (laboratory scale) and 75, 90 °C (pilot scale); moreover, the experimental Vfeed values were in the following ranges: 2.8 and 5.6 mL.min−1 (laboratory scale) and 59–197 mL.min−1 (pilot scale). With the coarse-scale approach, absolute average deviations (AAD) below 7% between experimental and calculated values were observed for Toutlet and Vfeed. However, large prediction errors (>10%) were observed for H, for which the experimental values were in the range of 2.4–4.5% for both scales. On the contrary, the finer-scale approach consisted of a plug-flow model, with incorporated drying kinetics and spray droplet sizes. This model could accurately predict Toutlet, H and d32, with AAD values below 10%. Both simulation and experiments are useful tools not only for spray drying optimization, but also for improving the oxidative stability of microencapsulated oils by target-oriented design.
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•A spray-drying process for the encapsulation of chia oil was modeled.•Coarse and finer-scale models were applied for laboratory and pilot-scale dryers.•Air outlet temperature and feed rate were accurately predicted by the coarse-scale model.•Better predictions for moisture content were obtained with the finer-scale model.•The finer-scale model can be used for a rapid estimation of spray-dryers' performance.
Although hematological abnormalities have been described among patients with influenza virus infection, little is known about their impact on the outcome of the patients. The aim of this study was to ...assess the frequency and clinical impact of severe hematological abnormalities in patients with confirmed influenza virus infection. This was an observational retrospective study including all adult patients with diagnosis of influenza virus infection hospitalized from January to May 2016 in our institution. Influenza virus infection was diagnosed by means of rRT-PCR assay performed on respiratory samples. Poor outcome was defined as a composite endpoint in which at least one of the following criteria had to be fulfilled: (a) respiratory failure, (b) SOFA ≥2, or (c) death. Two hundred thirty-nine patients were included. Applying the HLH-04 criteria for the diagnosis of hemophagocytic syndrome, cytopenias (hemoglobin ≤9 g/dl, platelets <100,000/μl or neutrophils <1,000/μl) were present in 51 patients (21%). Patients with hematological abnormalities showed higher SOFA scores, respiratory failure, septic shock and in-hospital mortality than the remaining patients. The composite endpoint was present in 33.3% in the cytopenias group vs. 13.3% in the group without cytopenias (p=0.001). In a multivariate analysis, variables associated with the composite endpoint were: use of steroids prior to present admission (OR: 0.12; 95% CI: 0.015–0.96, p=0.046), presence of any hematological abnormality (OR: 3.54; 95% CI:1.66–7.51, p= 0.001), and LDH>225 U/l (OR:4.45; CI:1–19.71, p=0.049). Hematological abnormalities are not uncommon among hospitalized patients with influenza virus infection, and they are associated with a poorer outcome.
Sunflower protein isolates and the proteases pepsin and pancreatin were used for the production of protein hydrolysates that inhibit angiotensin-I converting enzyme (ACE). Hydrolysates obtained after ...3 h of incubation with pepsin and 3 h with pancreatin were studied. An ACE inhibitory peptide with the sequence Phe-Val-Asn-Pro-Gln-Ala-Gly-Ser was obtained by G-50 gel filtration chromatography and high-performance liquid chromatography C18 reverse phase chromatography. This peptide corresponds to a fragment of helianthinin, the 11S globulin from sunflower seeds, which is the main storage protein in sunflower. These results show that sunflower seed proteins are a potential source of ACE inhibitory peptides when hydrolyzed with pepsin and pancreatin. Keywords: Sunflower protein hydrolysate; ACE inhibitors; bioactive peptides; Helianthus annuus L.
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