2,224 research outputs found
Enhancing infrastructure resilience in wildfire management to face extreme events: Insights from the Iberian Peninsula
Factors such as human activity and climate change are contributing to an increase in the frequency and intensity of wildfires. This problem has challenged society’s knowledge, response capacity, and resilience, revealing its inadequacy to cope with the new wildfire regime characterized by extreme wildfire events (EWE). Policies on wildfire management mainly focus on suppression and managing emergencies, which may be insufficient to reduce EWE’s incidence and cope with its impact. Consequently, there is a lack of tools to support decision-making in wildfire management in other important aspects, such as prevention and protection. This study examines global wildfire policies specifically in the Iberian Peninsula (Portugal and Spain), including cross-border policies. A GIS-based tool to evaluate different normal and extreme wildfire management policies is applied to a cross-border case study, paying attention to the impact on critical land-based transport systems. A relevant outcome of the tool application is that suppression must be complemented with other wildfire management strategies in the analyzed area. The gained insights can help stakeholders to improve decision-making in wildfire management to successfully address EWE.This work was partly financed by FCT/ MCTES through national funds (PIDDAC) under the R&D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE), under reference UIDB/ 04029/2020 (doi.org/10.54499/UIDB/04029/2020), and under the Associate Laboratory Advanced Production and Intelligent Systems ARISE under reference LA/P/0112/2020
How to trust size distributions obtained by single particle inductively coupled plasma mass spectrometry analysis
Single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) is a technique widely used to obtain direct information about the number concentration and the size distribution of nanoparticles in liquid suspensions. However, its methods still lack clear quality control strategies to confirm the validity of the information derived from them. Only the detection of the complete size distribution of the nanoparticles in a sample over the size critical value ensures obtaining unbiased quantitative information, otherwise information should be restricted to report the presence of nanoparticles over a certain size and number concentration since their actual total number concentration is underestimated and the size overestimated. Under the latter conditions, data processing produces histograms showing the tails of the incomplete size distributions, although apparently, complete distributions can also be obtained when particle events are recorded as peaks, as reported here for the first time. The occurrence of these misleading situations must be critically evaluated for each SP-ICP-MS analysis. An approach, based on estimation of size critical values and successive dilutions, is proposed for the assessment of the validity of the quantitative information obtained, together with specific criteria for reconsidering the information that can be derived from those measurements. The approach was verified with different case studies and applied to the analysis of complex nanomaterials, confirming the validity of the reported information by comparison with other techniques. A calculation tool is also included to facilitate the estimation of size critical values under experimental conditions
Eutrophication and macroalgal blooms in temperate and tropical coastal waters: Nutrient enrichment experiments with Ulva spp.
Receiving coastal waters and estuaries are among the most nutrient-enriched environments on earth, and one of the symptoms of the resulting eutrophication is the proliferation of opportunistic, fast-growing marine seaweeds. Here, we used a widespread macroalga often involved in blooms, Ulva spp., to investigate how supply of nitrogen (N) and phosphorus (P), the two main potential growth-limiting nutrients, influence macroalgal growth in temperate and tropical coastal waters ranging from low- to high-nutrient supplies. We carried out N and P enrichment field experiments on Ulva spp. in seven coastal systems, with one of these systems represented by three different subestuaries, for a total of nine sites. We showed that rate of growth of Ulva spp. was directly correlated to annual dissolved inorganic nitrogen (DIN) concentrations, where growth increased with increasing DIN concentration. Internal N pools of macroalgal fronds were also linked to increased DIN supply, and algal growth rates were tightly coupled to these internal N pools. The increases in DIN appeared to be related to greater inputs of wastewater to these coastal waters as indicated by high δ15N signatures of the algae as DIN increased. N and P enrichment experiments showed that rate of macroalgal growth was controlled by supply of DIN where ambient DIN concentrations were low, and by P where DIN concentrations were higher, regardless of latitude or geographic setting. These results suggest that understanding the basis for macroalgal blooms, and management of these harmful phenomena, will require information as to nutrient sources, and actions to reduce supply of N and P in coastal waters concerned.Fil: Teichberg, Mirta. Leibniz Center For Tropical Marine Research; AlemaniaFil: Fox, Sophia E.. Marine Biological Laboratory; Estados UnidosFil: Olsen, Ylva S.. Bangor University; Reino UnidoFil: Valiela, Ivan. Marine Biological Laboratory; Estados UnidosFil: Martinetto, Paulina Maria del Rosario. Universidad Nacional de Mar del Plata; ArgentinaFil: Iribarne, Oscar Osvaldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Muto, Elizabeti Yuriko. Universidade de Sao Paulo; BrasilFil: Petti, Monica A.V.. Universidade de Sao Paulo; BrasilFil: Corbisier, Thaïs N.. Universidade de Sao Paulo; BrasilFil: Soto-Jiménez, Martín. Universidad Nacional Autónoma de México; MéxicoFil: Páez-Osuna, Federico. Universidad Nacional Autónoma de México; MéxicoFil: Castro, Paula. University Of Coimbra; BrasilFil: Freitas, Helena. University Of Coimbra; BrasilFil: Zitelli, Andreina. Università Iuav Di Venezia; ItaliaFil: Cardinaletti, Massimo. Gruppo Veritas; ItaliaFil: Tagliapietra, Davide. Consiglio Nazionale delle Ricerche; Itali
Abrupt permafrost thaw triggers activity of copiotrophs and microbiome predators
Permafrost soils store a substantial part of the global soil carbon and nitrogen. However, global warming causes abrupt erosion and
gradual thaw, which make these stocks vulnerable to microbial decomposition into greenhouse gases. Here, we investigated the microbial response to abrupt in situ permafrost thaw. We sequenced the total RNA of a 1 m deep soil core consisting of up to 26 500-year-old
permafrost material from an active abrupt erosion site. We analysed the microbial community in the active layer soil, the recently
thawed, and the intact permafrost, and found maximum RNA:DNA ratios in recently thawed permafrost indicating a high microbial
activity. In thawed permafrost, potentially copiotrophic Burkholderiales and Sphingobacteriales, but also microbiome predators dominated the community. Overall, both thaw-dependent and long-term soil properties significantly correlated with changes in community composition, as did microbiome predator abundance. Bacterial predators were dominated in shallower depths by Myxococcota,
while protozoa, especially Cercozoa and Ciliophora, almost tripled in relative abundance in thawed layers. Our findings highlight the
ecological importance of a diverse interkingdom and active microbial community highly abundant in abruptly thawing permafrost,
as well as predation as potential biological control mechanism
Study of the chlorfenvinphos pesticide removal under different anodic materials and different reactor configuration
The present manuscript focuses on the study of the electrochemical oxidation of the insecticide Chlorfenvinphos (CVP). The assays were carried out under galvanostatic conditions using boron-doped diamond (BDD) and low-cost tin dioxide doped with antimony (Sb-doped SnO2) as anodes. The influence of the operating variables, such as applied current density, presence or absence of a cation-exchange membrane and concentration of supporting electrolyte, was discussed. The results revealed that the higher applied current density the higher degradation and mineralization of the insecticide for both anodes. The presence of the membrane and the highest concentration of Na2SO4 studied (0.1 M) as a supporting electrolyte benefited the oxidation process of CVP using the BDD electrode, while with the ceramic anode the elimination of CVP was lower under these experimental conditions. Although the BDD electrode showed the best performance, ceramic anodes appear as an interesting alternative as they were able to degrade CVP completely for the highest applied current density values. Toxicity tests revealed that the initial solution of CVP was more toxic than the samples treated with the ceramic electrode, while using the BDD electrode the toxicity of the sample increased
Adjustable conduits for guided peripheral nerve regeneration prepared from bi-zonal unidirectional and multidirectional laminar scaffold of type I collagen
Shortness of donor nerves has led to the development of nerve conduits that connect sectioned peripheral nerve stumps and help to prevent the formation of neuromas. Often, the standard diameters of these devices cannot be adapted at the time of surgery to the diameter of the nerve injured. In this work, scaffolds were developed to form filled nerve conduits with an inner matrix with unidirectional channels covered by a multidirectional pore zone. Collagen type I dispersions (5 mg/g and 8 mg/g) were sequentially frozen using different methods to obtain six laminar scaffolds (P1 to P5) formed by a unidirectional (U) pore/channel zone adjacent to a multidirectional (M) pore zone. The physicochemical and microstructural properties of the scaffolds were determined and compared, as well as their biodegradability, residual glutaraldehyde and cytocompatibility. Also, the Young's modulus of the conduits made by rolling up the bizonal scaffolds from the unidirectional to the multidirectional zone was determined. Based on these comparisons, the proliferation and differentiation of hASC were assessed only in the P3 scaffolds. The cells adhered, aligned in the same direction as the unidirectional porous fibers, proliferated, and differentiated into Schwann-like cells. Adjustable conduits made with the P3 scaffold were implanted in rats 10 mm sciatic nerve lesions to compare their performance with that of autologous sciatic nerve grafted lesions. The in vivo results demonstrated that the tested conduit can be adapted to the diameter of the nerve stumps to guide their growth and promote their regeneration.publishe
Analytical applications of single particle inductively coupled plasma mass spectrometry: a comprehensive and critical review
Single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) refers to the use of ICP-MS as a particle counting technique. When ICP-MS measurements are performed at very high data acquisition frequencies, information about (nano)particles containing specific elements and their dissolved forms can be obtained (element mass per particle, size and number and mass concentrations). As a result of its outstanding performance, SP-ICP-MS has become a relevant technique for the analysis of complex samples containing inorganic nanoparticles. This review discusses the maturity level achieved by the technique through the methods developed for the detection, characterisation and quantification of engineered and natural (nano)particles. The application of these methods in different analytical scenarios is comprehensively reviewed and critically discussed, with special attention to their current technical and metrological limitations. The emergent applications of SP-ICP-MS in the field of nanoparticle-tagged immunoassay and hybridization methods are also reviewed
Impact of the COVID-19 pandemic on tuberculosis management in Spain
Coronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Impacte; TuberculosiCoronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Impacto; TuberculosisCoronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Impact; TuberculosisBackground
The impact of COVID-19 on the diagnosis and management of tuberculosis (TB) patients is unknown.
Methods
Participating centres completed a structured web-based survey regarding changes to TB patient management during the COVID-19 pandemic. The study also included data from participating centres on patients aged ≥18 diagnosed with TB in 2 periods: March 15 to June 30, 2020 and March 15 to June 30, 2019. Clinical variables and information about patient household contacts were retrospectively collected.
Results
A total of 7 (70%) TB units reported changes in their usual TB team operations. Across both periods of study, 169 patients were diagnosed with active TB (90 in 2019, 79 in 2020). Patients diagnosed in 2020 showed more frequent bilateral lesions in chest X-ray than patients diagnosed in 2019 ( P = 0.004). There was a higher percentage of latent TB infection and active TB among children in households of patients diagnosed in 2020, compared with 2019 ( P = 0.001).
Conclusions
The COVID-19 pandemic has caused substantial changes in TB care. TB patients diagnosed during the COVID-19 pandemic showed more extended pulmonary forms. The increase in latent TB infection and active TB in children of patient households could reflect increased household transmission due to anti-COVID-19 measures.This research did not receive any specific grant from funding agencies in the public, commercial or not-for-profit sectors.MLA was supported by a postdoctoral grant “Rio Hortega” and ASM was supported by a postdoctoral grant “Juan Rodés” (JE18/00022) from the Instituto de Salud Carlos III through the Spanish Ministry of economy and competitiveness
Technology-assisted stroke rehabilitation in Mexico: a pilot randomized trial comparing traditional therapy to circuit training in a Robot/technology-assisted therapy gym
Background Stroke rehabilitation in low- and middle-income countries, such as Mexico, is often hampered by lack of clinical resources and funding. To provide a cost-effective solution for comprehensive post-stroke rehabilitation that can alleviate the need for one-on-one physical or occupational therapy, in lower and upper extremities, we proposed and implemented a technology-assisted rehabilitation gymnasium in Chihuahua, Mexico. The Gymnasium for Robotic Rehabilitation (Robot Gym) consisted of low- and high-tech systems for upper and lower limb rehabilitation. Our hypothesis is that the Robot Gym can provide a cost- and labor-efficient alternative for post-stroke rehabilitation, while being more or as effective as traditional physical and occupational therapy approaches. Methods A typical group of stroke patients was randomly allocated to an intervention (n = 10) or a control group (n = 10). The intervention group received rehabilitation using the devices in the Robot Gym, whereas the control group (n = 10) received time-matched standard care. All of the study subjects were subjected to 24 two-hour therapy sessions over a period of 6 to 8 weeks. Several clinical assessments tests for upper and lower extremities were used to evaluate motor function pre- and post-intervention. A cost analysis was done to compare the cost effectiveness for both therapies. Results No significant differences were observed when comparing the results of the pre-intervention Mini-mental, Brunnstrom Test, and Geriatric Depression Scale Test, showing that both groups were functionally similar prior to the intervention. Although, both training groups were functionally equivalent, they had a significant age difference. The results of all of the upper extremity tests showed an improvement in function in both groups with no statistically significant differences between the groups. The Fugl-Meyer and the 10 Meters Walk lower extremity tests showed greater improvement in the intervention group compared to the control group. On the Time Up and Go Test, no statistically significant differences were observed pre- and post-intervention when comparing the control and the intervention groups. For the 6 Minute Walk Test, both groups presented a statistically significant difference pre- and post-intervention, showing progress in their performance. The robot gym therapy was more cost-effective than the traditional one-to-one therapy used during this study in that it enabled therapist to train up to 1.5 to 6 times more patients for the approximately same cost in the long term. Conclusions The results of this study showed that the patients that received therapy using the Robot Gym had enhanced functionality in the upper extremity tests similar to patients in the control group. In the lower extremity tests, the intervention patients showed more improvement than those subjected to traditional therapy. These results support that the Robot Gym can be as effective as traditional therapy for stroke patients, presenting a more cost- and labor-efficient option for countries with scarce clinical resources and funding. Trial registration ISRCTN98578807
Magnetobiochronology of lower Pliocene marine sediments from the lower Guadalquivir Basin: insights into the tectonic evolution of the Strait of Gibraltar area
The Gibraltar Arc is a complex tectonic region, and several competing models have been proposed to explain its evolution. We studied the sedimentary fill of the Guadalquivir Basin to identify tectonic processes that were occurring when the reopening of the Strait of Gibraltar led to the reestablishment of Mediterranean outflow. We present a chronostratigraphic framework for the Lower Pliocene sediments from the lower Guadalquivir Basin (SW Spain). The updated chronology is based on magnetobiostratigraphic data from several boreholes. Our results show that the studied interval in the La Matilla core is in the early Pliocene section, providing better constraints on the sedimentary evolution of the basin during that period. Migrating depositional facies led to a younger onset of sandy deposition basinward. At the northwestern passive margin, a 0.7 m.y. period of sedimentary bypass related to a sharp decrease in sedimentation rates and lower sea levels resulted from the tectonic uplift of the forebulge. In contrast, high sedimentation rates with continuous deep-marine sedimentation are recorded at the basin center due to continuous tectonic subsidence and west-southwestward progradation of axial depositional systems. The marginal forebulge uplift, continuous tectonic basinal subsidence, and southward progradation of clinoforms in the early Pliocene can be explained by the pull of a lithospheric slab beneath the Gibraltar Arc as the Strait of Gibraltar opened. These findings are, to our knowledge, the first reported sedimentary expression of slab pull beneath the Betics related to the opening of the Strait of Gibraltar after the Messinian salinity crisis
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