2,268 research outputs found

    Shortcomings of international standard iso 9223 for the classification, determination, and estimation of atmosphere corrosivities in subtropical archipelagic conditions—The case of the Canary Islands (Spain)

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    grant ProID2017010042The classification, assessment, and estimation of the atmospheric corrosivity are fixed by the ISO 9223 standard. Its recent second edition introduced a new corrosivity category for extreme environments CX, and defined mathematical models that contain dose–response functions for normative corrosivity estimations. It is shown here that application of the ISO 9223 standard to archipelagic subtropical areas exhibits major shortcomings. Firstly, the corrosion rates of zinc and copper exceed the range employed to define the CX category. Secondly, normative corrosivity estimation would require the mathematical models to be redefined introducing the time of wetness and a new set of operation constants.publishersversionpublishe

    Prevalence of dementia in Latin America: a collaborative study of population-based cohorts

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    Background: Dementia is becoming a major public health problem in Latin America (LA), yet epidemiological information on dementia remains scarce in this region. This study analyzes data from epidemiological studies on the prevalence of dementia in LA and compares the prevalence of dementia and its causes across countries in LA and attempts to clarify differences from those of developed regions of the world. Methods: A database search for population studies on rates of dementia in LA was performed. Abstracts were also included in the search. Authors of the publications were invited to participate in this collaborative study by sharing missing or more recent data analysis with the group. Results: Eight studies from six countries were included. The global prevalence of dementia in the elderly (≥65 years) was 7.1% (95% CI: 6.8–7.4), mirroring the rates of developed countries. However, prevalence in relatively young subjects (65–69 years) was higher in LA studies The rate of illiteracy among the elderly was 9.3% and the prevalence of dementia in illiterates was two times higher than in literates. Alzheimer’s disease was the most common cause of dementia. Conclusions: Compared with studies from developed countries, the global prevalence of dementia in LA proved similar, although a higher prevalence of dementia in relatively young subjects was evidenced, which may be related to the association between low educational level and lower cognitive reserve, causing earlier emergence of clinical signs of dementia in the LA elderly population

    Analysis of the Yield of Radish (Raphanus Sativus L.) Fertilized with Compost Based on Organic Waste from Markets and its Relationship with its Stomatal Density

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    For higher yields in vegetable cultivation, the availability of soil nutrients must be improved. Therefore, the aim of this research was to establish the relationship between stomatal density and the yield of the radish crop fertilized with compost made from organic market waste. A completely randomized block design was used, which consisted of 3 blocks and 5 treatments, which were T1, T2, T3, T4 and T5 with 00, 10, 15, 15, 20 and 25 g compost/plant respectively. The physical characteristics of the plants were evaluated from sowing to harvest and the data obtained were processed by analysis of variance and Duncan's test. Chemical analysis of the compost and soil was carried out, as well as a foliar analysis to determine the nutrient concentration by treatment. The results determined that the treatment (T4) stood out in plant length with 28.96 cm, plant weight with 43.33 g, yield of 10.82 t/ha and bulb diameter of 3.92 cm; likewise, in the concentration of nutrients in the leaves, the treatment (T5) highlighted in N with 5.94%, Ca 4.84%, Mg 1.29%, Zn 64.58 ppm and a stomatal density of 642 stomas/mm2. It is concluded that, at an adequate dose of compost, the concentration of nutrients increases, as well as the stomatal density, resulting in higher yields

    Stomatal Density and its Relationship with Yield of Radish (Raphanus Sativus L.) Fertilized with Biol Produced from Sugar Cane Residues

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    The impact of agro-industrial waste can be reduced by using it in crop fertilization. The aim of this study was to evaluate the stomatal density and yield of radish (Raphanus Sativus L.) fertilized with biol at different concentrations, produced from sugar cane residues. A completely randomized blocks design statistical model was used, which consisted of 5 tests with 3 repetitions for each one, being T1 the control trial, and T2, T3, T4 and T5 the treatments using 2, 3, 4 and 5 L of biol in 200 L of water respectively. In terms of crop physical characteristics, the T5 treatment excelled in plant length, equatorial diameter, plant weight, as well as yield with 12.71 t/ha. Likewise, in the chemical analysis of the radish leaves, the T5 treatment showed an increase in K, Ca, Zn and MN, while the T2 did it in N, P and Cu, the T3 in Fe and the T4 in Mg. In terms of stomatal density, T5 stood out with 122 stomatal/mm2. Based on this, it is concluded that the increase in the dose of biol influences the increase in nutrient and stomatal density and hence the yield of the radish crop

    High serum levels of tissue inhibitor of matrix metalloproteinase-1 during the first week of a malignant middle cerebral artery infarction in non-surviving patients

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    Background: Higher circulating levels of tissue inhibitor of matrix metalloproteinases (TIMP)-1 early after ischemic stroke have been associated with lower survival. The objectives of this study were to determine serum TIMP-1 levels during the first week of a severe cerebral infarction in surviving and non-surviving patients, and whether those levels during the first week could be used as a mortality biomarker for these patients. Methods: We included patients with severe malignant middle cerebral artery infarction (MMCAI) defined as computer tomography showing ischaemic changes in more than 50% of the middle cerebral artery territory and Glasgow Coma Scale (GCS) ≤ 8. We measured serum levels of matrix metalloproteinases (MMP)-9 and TIMP-1. End-point study was 30-day mortality. Results: We found higher TIMP-1 concentrations at days 1 (p < 0.001), 4 (p = 0.001), and 8 (p = 0.03) of MMCAI in nonurviving (n = 34) than in surviving (n = 34) patients. We found lower serum MMP-9 concentrations at day 1 (p = 0.03) of MMCAI and no significant differences at days 4 and 8. ROC curve analysis of TIMP-1 concentrations performed at days 1, 4, and 8 of MMCAI showed an area under curve to predict 30-day mortality of 81% (p < 0.001), 80% (p < 0.001) and 72% (p = 0.07) respectively. Conclusions: The new findings of our study were that non-surviving MMCAI patients showed higher serum TIMP-1 levels during the first week of MMCAI that surviving patients, and those levels during the first week of MMCAI could be used as mortality biomarkers

    Polystyrene nanoparticles slurry as an additive for developing insulating and waterproof gypsum composites

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    Lightweight gypsum composites with improved thermal and waterproof properties were produced by using a concentrated slurry containing polystyrene nanoparticles (NPS) as an additive. The NPS/Hemihydrate mass ratio was varied between 0.00 and 0.42. The density of the composites decreased with the increase of the NPS/Hemihydrate mass ratio, due to the change in the internal structure to a more lamellar one with crystals of larger size that grow also in a less compact distribution. This also caused an increase of the porosity (from 0.47 to 0.51) and a reduction in the thermal conductivity from 0.354 W m-1K−1 (NPS/Hem = 0) to 0.225 W m-1K−1 at 32 °C for the composite manufactured with the maximum NPS amount (NPS/Hem = 0.42). The thermal conductivity decrease allowed to reduce the final temperature at the steady state up to 2.5 °C compared with the unmodified gypsum, when they were exposed to a heat source at 45 °C. In addition, it was observed by SEM and TGA that the NPSs were distributed homogeneously throughout the gypsum composites blocks. Although the maximum compressive and flexural strengths decreased with the increase of NPS amount up to 76 and 61 %, respectively; all the synthesized lightweight gypsum blocks satisfied the European standard regulation EN 13279–1. The waterproof properties were measured by the contact angle, passing from 26.2° to 141.5 ° when changing from 0.0 NPS/Hem ratio to the maximum amount

    Unravelling Hominin Activities in the Zooarchaeological Assemblage of Barranco Leon (Orce, Granada, Spain)

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    Little is known about the subsistence practices of the first European settlers, mainly due to the shortage of archaeological sites in Europe older than a million years. This article contributes to the knowledge of the subsistence of the first Europeans with new zooarchaeology and taphonomic data from the Palaeolithic site of Barranco Leon (Orce, Granada, Spain). We present the results of the analysis of the faunal assemblages retrieved in the context of new excavations undertaken between 2016 and 2020. We have followed a standard methodology for the identification and quantification of species, mortality profiles, skeletal representation and taphonomic analysis. With regard to the taphonomic evidence, we have documented the extent of rounding, abrasion and other alterations. Finally, we examined traces from the activities of carnivores and hominins that led to the accumulation and alteration of the bone assemblages. Results indicate that the archaeo-paleontological deposits from Barranco Leon present a dual-patterned mixed taphonomic origin. The first phase primarily involved waterborne processes (BL-D1), which led to the accumulation of lithic raw materials, a few archaeological stone tools, and some faunal remains with percussion and cutmarks. The second phase (BL-D2) contains several stone tools associated with faunal remains with more anthropogenic alterations, such as cutmarks and percussion marks. After analysing the Barranco Leon zooarchaeological assemblage, the present study concludes that hominins had access to the meat and within-bone nutrients of animals of diverse sizes. However, the specific carcass acquisition mechanisms that hominins followed are less certain because the presence of tooth marks suggests that carnivores also played a role in the accumulation and modification of the Barranco Leon faunal assemblage.Peer reviewe

    An integrated multi-omics approach identifies the landscape of interferon-α-mediated responses of human pancreatic beta cells

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    Interferon-α (IFNα), a type I interferon, is expressed in the islets of type 1 diabetic individuals, and its expression and signaling are regulated by T1D genetic risk variants and viral infections associated with T1D. We presently characterize human beta cell responses to IFNα by combining ATAC-seq, RNA-seq and proteomics assays. The initial response to IFNα is characterized by chromatin remodeling, followed by changes in transcriptional and translational regulation. IFNα induces changes in alternative splicing (AS) and first exon usage, increasing the diversity of transcripts expressed by the beta cells. This, combined with changes observed on protein modification/degradation, ER stress and MHC class I, may expand antigens presented by beta cells to the immune system. Beta cells also up-regulate the checkpoint proteins PDL1 and HLA-E that may exert a protective role against the autoimmune assault. Data mining of the present multi-omics analysis identifies two compound classes that antagonize IFNα effects on human beta cells
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