The Spanish health system is made up of seventeen regional health systems. Through the official reporting systems, some inconsistencies and differences in case fatality rates between Autonomous ...Communities (CC.AA.) have been observed. Therefore the objective of this paper is to compare COVID-19 case fatality rates across the Spanish CC.AA.
Observational descriptive study. The COVID-19 case fatality rate (CFR) was estimated according to the official records (CFR-PCR+), the daily mortality monitory system (MoMo) record (CFR-Mo), and the seroprevalence study ENE-COVID-19 (Estudio Nacional de sero Epidemiologia Covid-19) according to sex, age group and CC.AA. between March and June 2020. The main objective is to detect whether there are any differences in CFR between Spanish Regions using two different register systems, i. e., the official register of the Ministry of Health and the MoMo.
Overall, the CFR-Mo was higher than the CFR-PCR+, 1.59% vs 0.98%. The differences in case fatality rate between both methods were significantly higher in Castilla La Mancha, Castilla y León, Cataluña, and Madrid. The difference between both methods was higher in persons over 74 years of age (CFR-PCR+ 7.5% vs 13.0% for the CFR-Mo) but without statistical significance. There was no correlation of the estimated prevalence of infection with CFR-PCR+, but there was with CFR-Mo (R2 = 0.33). Andalucía presented a SCFR below 1 with both methods, and Asturias had a SCFR higher than 1. Cataluña and Castilla La Mancha presented a SCFR greater than 1 in any scenario of SARS-CoV-2 infection calculated with SCFR-Mo.
The PCR+ case fatality rate underestimates the case fatality rate of the SARS-CoV- 2 virus pandemic. It is therefore preferable to consider the MoMo case fatality rate. Significant differences have been observed in the information and registration systems and in the severity of the pandemic between the Spanish CC.AA. Although the infection prevalence correlates with case fatality rate, other factors such as age, comorbidities, and the policies adopted to address the pandemic can explain the differences observed between CC.AA.
Given the importance that concentrating solar power technologies have had in recent years, the interaction between humid atmospheres in which SO2 is the main pollutant and the metal reflecting layers ...of the solar concentrators is a major concern that should be addressed. Previous durability studies have urged the importance of designing an accelerated aging test protocol for simulating aggressive industrial atmospheres that solar reflector materials are bound to encounter. Therefore, three types of reflectors were tested in an acid-rain (or Kesternich) chamber at various temperatures and gas concentrations based on the DIN 50018 and ISO 6988 standards. The results showed the significant effect of high SO2 concentrations rather than high temperatures on silvered-glass reflectors, although synergy should not be disregarded. Strong reductions in specular reflectance were found for one type of silvered reflector compared to another type, highlighting the significance of material processing and its effects on their final performance. Aluminum reflectors were not damaged as much as silvered-glass reflectors, but under microscopic inspection, a wide range of noticeable corrosion defects could be found in all the materials. Comparisons between the most representative Kesternich test and samples from an outdoor industrial site permitted realistic lifetime correlations for commercial silvered-glass reflectors.
Main corrosion features that appeared in the reflective area of Type 1 silvered-glass reflectors at the end of the different corrosion tests. K_0_25 is the test at 0 dm3 SO2, 25 °C, K_0_40 is the test at 0 dm3 SO2, 40 °C, K_0_50 is the test at 0 dm3 SO2, 50 °C, K_0.2_40 is the test at 0.2 dm3 SO2, 40 °C, K_1_25 is the test at 1 dm3 SO2, 25 °C, K_1_40 is the test at 1 dm3 SO2, 40 °C, K_1_50 is the test at 1 dm3 SO2, 50 °C, K_2_40 is the test at 2 dm3 SO2, 40 °C, N is the sum of the number of corrosion spots visible to the naked eye at the end of testing on a 300 cm2 total reflector surface, Max. Pen. is the maximum penetration of corrosion near the edge (μm), Δρλ,φ is the mean increment in monochromatic specular reflectance on reflector surfaces not predamaged (-), Total Corr. is the mean total corrosion of the whole reflector surface (%). Display omitted
•Suggested Kesternich tests for reflectors are 1 dm3 SO2 at 50 °C, 2 dm3 SO2 at 40 °C.•2 dm3 SO2 at 40 °C test implies an acceleration factor of 57 compared to a real site.•Major degradation appeared in Type 1 reflectors after the most aggressive tests.•Undamaged Type 2 reflectors had more and larger corrosion spots than Type 1.•Aluminum reflectors were corroded in a lower degree than silvered-glass reflectors.
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•Sulphurous atmospheres do harm the performance of certain CSP reflectors.•Traditional measurements do not detect almost any reflectance loss after the ageing.•The main degradation ...pattern in silvered glass reflectors are corrosion spots.•EDS microanalyses reveal the reaction between the H2S and the silver layer.•Aluminium reflectors do not corrode in the presence of the sulphurous gas.
The degradation of reflector materials for concentrating solar thermal applications is analysed. Corrosion of their metallic reflective layer is considered a major problem in facilities which are located near industrial sites, where reduced sulphur gases may be present. Accelerated ageing tests were performed to study the influence of H2S on the corrosion of two types of silvered glass reflectors and one aluminium reflector. Different degradation patterns were found for silvered glass reflectors, whereas aluminium reflectors did not corrode in the presence of the sulphurous gas. Therefore, industrial pollution caused by this type of gas may decrease the solar collectors’ performance.
Durability studies of solar reflectors: A review García-Segura, A.; Fernández-García, A.; Ariza, M.J. ...
Renewable & sustainable energy reviews,
September 2016, 2016-09-00, 20160901, Letnik:
62
Journal Article
Recenzirano
Reflectors are a vital part of a concentrating solar thermal power plant. One of their most important characteristics is their durability, which entails the maintenance of their optical properties ...throughout their service lifetime, aimed at 10–30 years or more. The assessment of their optical durability involves the design of two types of aging tests, outdoor exposure testing under real ambient conditions and accelerated exposure testing in weathering chambers under simulated conditions. After exposure to different stress factors for certain periods of time, the optical performance of reflectors is evaluated mainly in terms of reflectance, but also regarding qualitative parameters such as their visual appearance and degradation patterns. The ultimate goal of a durability study is to conceive meaningful accelerated testing procedures that simulate real outdoor degradation in a short time and provide service lifetime estimates for a certain type of reflector at a specific site. To achieve this, more research on service lifetime prediction should be conducted and the standardization of accelerated testing procedures and reflectance evaluation methods should become widespread, to obtain comparable representative results. In this article, the most significant durability studies performed on the three main types of solar reflectors (glass-based, aluminum and silvered-polymer) and prospective approaches for improving future endeavors are discussed.
•Correlate Electrical Resistivity Tomography with metallic concentration data.•Modelling spatial distribution of heavy metal concentrations statistically.•Assessment of a forsaken phosphogypsum pond ...efficiently.
One of the wastes generated in fertiliser production from phosphoric rock is phosphogypsum, whose mismanagement lead to environmental and health risks. Therefore, a detailed evaluation of the chemical composition of phosphogypsum is necessary to determine effective means of its management. Due to the high amount of generated waste, the cost and time consumed for this characterisation by chemical analysis is limiting. Hence, efficient tools should be developed to predict the chemical composition of this waste. Thus, this study aims to: 1) determine the physic-chemical characterisation of phosphogypsum pond using geochemical and geophysical techniques and 2) predict the heavy metals spatial distribution through statistical models. Results show that the most concentrate metal is chromium with a maximum of ≈900 mg.kg−1 and cadmium is the least concentrated (maximum ≈23 mg.kg-1). The Electrical Resistivity Tomography revealed the superposition of two layers. The top one (waste) presents low resistivity (≈17Ω.m) while the bottom layer shows higher resistivity (>124Ω.m). Metal concentrations and resistivities were combined by applying non-linear regression models. Cr showed the strongest correlation (R2 = 0.68), yielding an accurate model that was used for revealing the spatial distribution of the highest Cr concentrations in the pond, with the consequent reduction of expensive traditional methods.
The lack of environmental regulations before 1998 brought about significant ecological consequences in Europe. There are 4,000,000 ha potentially contaminated by waste, resulting from industrial ...activity. These sites present abnormal values of salinity, alkalinity, and organic and inorganic pollutants. A representative example of this is the production of fertiliser derived from phosphoric rock through the wet acid process which mainly produces phosphogypsum and pyrite ashes. For each tonne of fertiliser produced, five tonnes of phosphogypsum are generated, which in most of the cases were simply piled into non-conditionate deposits; currently, there is no information about these deposits. Hence, fast and affordable methodologies should be developed to calculate the volume contained in the existing waste deposits. Thus, this study aims to: i) scan the industrial area selected in order to identify the distribution and possible variants of the waste that make up the configuration of geoelectrical profiles and boreholes, and ii) accurately determine the volume contained in the chosen deposits by merging Electrical Resistivity Tomography with LiDAR point cloud. Results show a range of deposit volumes that run from 4900 m3 to 59,300 m3. The density of LiDAR point cloud (1 point/m2) ensures metric precision for the superficial layer. The Electrical Resistivity Tomography revealed the geometry of the deposits that superposes two layers marking the border between waste and natural terrain, and the boreholes guarantee the exactness of the waste layer thickness. This synergistic combination of Electrical Resistivity Tomography with LiDAR point cloud yields an accurate method that we used to calculate the volume of waste present in the deposits.
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•Correlation of borehole data with Electrical Resistivity Tomography profiles•Topographic layer modelling based on LiDAR point cloud•Volumetric assessment of forsaken waste deposits
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•SEM, EDS and FIB are employed to study corrosion in Ag-glass solar reflectors.•Polluting gases (SO2, H2S and NOx) have a great influence on reflector degradation.•For all gas ...atmospheres, the Cu-layer is the critical component. It is corroded first and protects silver.•Corrosion products and mechanisms depend on gas type, humidity and temperature•Heavy metals of the rear protective paints (Zn, Fe) also play a significant role.
Silvered-glass solar reflectors consist of a reflective layer (RL), composed of silver and copper thin-films, back-protected by paint layers on a glass plate. The RL is prone to corrosion, especially in industrial atmospheres with polluting gases. After applying accelerated aging tests with gaseous pollutants (SO2, H2S, NO2), SG-R samples are studied by SEM and EDS, including FIB preparation. As expected the copper thin-film is firstly corroded, followed by the silver corrosion. Deposits of different corrosion products were found on the reflector’s surface, depending on the polluting gas used. The rear protective paint layers also play an active role.
Prolactin (PRL) is a peptidic hormone that displays pleiotropic functions in the organism including different actions in the brain. PRL exerts a neuroprotective effect against excitotoxicity produced ...by glutamate (Glu) or kainic acid in both in vitro and in vivo models. It is well known that Glu excitotoxicity causes cell death through apoptotic or necrotic pathways due to intracellular calcium (Ca2+ i) overload. Therefore, the aim of the present study was to assess the molecular mechanisms by which PRL maintains cellular viability of primary cultures of rat hippocampal neurons exposed to Glu excitotoxicity. We determined cell viability by monitoring mitochondrial activity and using fluorescent markers for viable and dead cells. The intracellular calcium level was determined by a fluorometric assay and proteins involved in the apoptotic pathway were determined by immunoblot. Our results demonstrated that PRL afforded neuroprotection against Glu excitotoxicity, as evidenced by a decrease in propidium iodide staining and by the decrease of the LDH activity. In addition, the MTT assay shows that PRL maintains normal mitochondrial activity even in neurons exposed to Glu. Furthermore, the Glu-induced intracellular Ca2+i overload was attenuated by PRL. These data correlate with the reduction found in the level of active caspase-3 and the pro-apoptotic ratio (Bax/Bcl-2). Concomitantly, PRL elicited the nuclear translocation of the transcriptional factor NF-κB, which was detected by immunofluorescence and confocal microscopy. To our knowledge, this is the first report demonstrating that PRL prevents Glu excitotoxicity by a mechanism involving the restoration of the intracellular calcium homeostasis and mitochondrial activity, as well as an anti-apoptotic action possibly mediated by the activity of NF-κB. Overall, the current results suggest that PRL could be of potential therapeutic advantage in the treatment of neurodegenerative diseases.
Single immune checkpoint blockade in advanced neuroendocrine neoplasms (NENs) shows limited efficacy; dual checkpoint blockade may improve treatment activity. Dune (NCT03095274) is a non-randomized ...controlled multicohort phase II clinical trial evaluating durvalumab plus tremelimumab activity and safety in advanced NENs. This study included 123 patients presenting between 2017 and 2019 with typical/atypical lung carcinoids (Cohort 1), G1/2 gastrointestinal (Cohort 2), G1/2 pancreatic (Cohort 3) and G3 gastroenteropancreatic (GEP) (Cohort 4) NENs; who progressed to standard therapies. Patients received 1500 mg durvalumab and 75 mg tremelimumab for up to 13 and 4 cycles (every 4 weeks), respectively. The primary objective was the 9-month clinical benefit rate (CBR) for cohorts 1-3 and 9-month overall survival (OS) rate for Cohort 4. Secondary endpoints included objective response rate, duration of response, progression-free survival according to irRECIST, overall survival, and safety. Correlation of PD-L1 expression with efficacy was exploratory. The 9-month CBR was 25.9%/35.5%/25% for Cohorts 1, 2, and 3 respectively. The 9-month OS rate for Cohort 4 was 36.1%, surpassing the futility threshold. Benefit in Cohort 4 was observed regardless of differentiation and Ki67 levels. PD-L1 combined scores did not correlate with treatment activity. Safety profile was consistent with that of prior studies. In conclusion, durvalumab plus tremelimumab is safe in NENs and shows modest survival benefit in G3 GEP-NENs; with one-third of these patients experiencing a prolonged OS.
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