To determine whether VDPhys/VT is associated with coagulation activation and outcomes.
We enrolled patients with COVID-19 pneumonia who were supported by invasive mechanical ventilation and were ...monitored using volumetric capnography. Measurements were performed during the first 24 h of mechanical ventilation. The primary endpoint was the likelihood of being discharge alive on day 28.
Sixty patients were enrolled, of which 25 (42%) had high VDPhys/VT (>57%). Patients with high vs. low VDPhys/VT had higher APACHE II (108-13 vs. 86-9 points, p = 0.002), lower static compliance of the respiratory system (3524–46 mL/cmH2O vs. 4237–45 mL/cmH2O, p = 0.005), and higher D-dimer levels (12461050–1594 ng FEU/mL vs. 792538–1159 ng FEU/mL, p = 0.001), without differences in P/F ratio (157112–226 vs. 168136–226, p = 0.719). Additionally, D-dimer levels correlated with VDPhys/VT (r = 0.530, p < 0.001), but not with the P/F ratio (r = −0.103, p = 0.433). Patients with high VDPhys/VT were less likely to be discharged alive on day 28 (32% vs. 71%, aHR = 3.3931.161–9.915, p = 0.026).
In critically ill COVID-19 patients, increased VDPhys/VT was associated with high D-dimer levels and a lower likelihood of being discharged alive. Dichotomic VDPhys/VT could help identify a high-risk subgroup of patients neglected by the P/F ratio.
•An increased respiratory dead space is a frequent finding in COVID-19 ARDS.•Coagulation activation correlates with respiratory dead space in these patients.•A respiratory dead space higher than 57% was associated with worse outcome.
Extreme drought events have negative effects on forest diversity and functioning. At the species level, however, these effects are still unclear, as species vary in their response to drought through ...specific functional trait combinations. We used long‐term demographic records of 21,821 trees and extensive databases of traits to understand the responses of 338 tropical dry forests tree species to ENSO2015, the driest event in decades in Northern South America. Functional differences between species were related to the hydraulic safety‐efficiency trade‐off, but unexpectedly, dominant species were characterised by high investment in leaf and wood tissues regardless of their leaf phenological habit. Despite broad functional trait combinations, tree mortality was more widespread in the functional space than tree growth, where less adapted species showed more negative net biomass balances. Our results suggest that if dry conditions increase in this ecosystem, ecological functionality and biomass gain would be reduced.
Extreme drought events have negative effects on forest diversity and functioning. We used long‐term demographic records of 21,821 trees and extensive databases of traits to understand the responses of 338 tropical dry forests tree species to an extreme. Our results indicate that irrespective of the drought adaptations, most trees will be negatively affected under drier scenarios predicted for tropical dry forests.
Abstract
We tested the idea that functional trade‐offs that underlie species tolerance to drought drive shifts in community composition via their effects on demographic processes and subsequently on ...shifts in species' abundance. Using data from 298 tree species from tropical dry forests during the extreme ENSO‐2015, we scaled‐up the effects of trait trade‐offs from individuals to communities. Conservative wood and leaf traits favoured slow tree growth, increased tree survival and positively impacted species abundance and dominance at the community‐level. Safe hydraulic traits, on the other hand, were related to demography but did not affect species abundance and communities. The persistent effects of the conservative–acquisitive trade‐off across organizational levels is promising for generalization and predictability of tree communities. However, the safety–efficient trade‐off showed more intricate effects on performance. Our results demonstrated the complex pathways in which traits scale up to communities, highlighting the importance of considering a wide range of traits and performance processes.
Introduction: The litterfall production, foliar nutrient dynamics and decomposition are essential to maintain nutrient cycling, soil fertility, and carbon regulation in terrestrial ecosystems. With ...several studies addressing the variation of these processes, their dynamics in tropical dry forests (TDFs) remain unclear, due to its complex interaction of biotic and abiotic factors. Objective: To evaluate litterfall, nutrient potential return and use efficiency, and decomposition variation in a TDF successional gradient in Tolima, Colombia. Methods: We quantified litterfall from November 2017 to October 2019 in 12 plots distributed in four successional stages: initial, early, intermediate, and late forests. We identified key tree species in foliar litter production and characterized the foliar decomposition of these species. At the community level, we quantified the C, N and P potential return, the N and P use efficiency, and the C:N and N:P ratio. Subsequently, we analyze relationships between vegetation characteristics and some soil chemical properties with these ecological processes. Results: We found that total litterfall in late forests (8.46 Mg ha-1 y-1) was double that found in initial forests (4.45 Mg ha-1 y-1). Decomposition was higher in initial (k = 1.28) compared to intermediate (k = 0.97) and late forests (k = 0.87). The nutrient potential return didn’t change along succession, but it did show differences between study sites. The structural development and species richness favored litterfall, while soil chemical conditions influenced nutrient returns and decomposition. Conclusions: TDFs could recover key ecosystem function related to litterfall and nutrient dynamics after disturbances cessation; however, the soil quality is fundamental in return and release of nutrients.
Hantavirus cardiopulmonary syndrome (HCPS) is a severe respiratory illness primarily associated with microvascular endothelial changes, particularly in the lungs. However, the role of the pulmonary ...epithelium in HCPS pathogenesis remains unclear. This study explores the potential of soluble Receptors for Advanced Glycation End-products (sRAGE) as a biomarker for assessing pulmonary epithelial damage in severe HCPS, challenging the prevailing view that endothelial dysfunction is the sole driver of this syndrome. We conducted a cross-sectional study on critically ill HCPS patients, categorizing them into mild HCPS, severe HCPS, and negative control groups. Plasma sRAGE levels were measured, revealing significant differences between the severe HCPS group and controls. Our findings suggest that sRAGE holds promise as an indicator of pulmonary epithelial injury in HCPS and may aid in tracking disease progression and guiding therapeutic strategies. This study brings clarity on the importance of investigating the pulmonary epithelium’s role in HCPS pathogenesis, offering potential avenues for enhanced diagnostic precision and support in this critical public health concern.
The interfacial capacitance measured in electrochemical experiments is usually considered to be independent of the faradaic processes involved at the electrode surface. In this work, we report on the ...use of a double modulation technique, which allows the simultaneous measurement of electrochemical impedance spectroscopy (EIS) and modulation of the interfacial capacitance transfer function (MICTF). We show that the capacitance ascribed to the response of passive films formed on pure iron electrodes in phosphoric acid solution exhibits two different time‐constants in low frequency domains, namely the response of intrinsic properties of the film linked to charge carriers and a relaxation ascribed to the thickness relaxation of the oxide film. Interestingly, the low frequency limit of MICTF is in good agreement with the capacitance obtained from EIS measurements. A detailed data analysis allows determination of both, the capacitance of the oxide film and the double layer capacitance to the overall capacitance to be measured. This technique thus provides a unique way of analysing the different contributions ascribed to the relaxation of the interfacial capacitance.
A double modulation technique based on electrochemical impedance spectroscopy measurements is used to study thin passive film formed on iron electrodes. It is shown that this technique provided a unique way to deconvolute the different contributions involved in the relaxation of the interfacial capacitance, including the relaxation of charge carriers and the relaxation of film thickness.
•Cysteine promotes the direct electron transfer of SOD.•A thermodynamics analysis of SOD adsorption processes was carried out.•Density charge, surfaces tension, surfaces excess and free energy of ...adsorption of Cys and SOD were obtained by differential capacitance measurements.•The orientation of adsorbed SOD was rationalized by electrostatic potential calculations.
Modification of gold electrodes with cysteine, improve superoxide dismutase (SOD) electron transfer for superoxide quantification in a typical third-generation electrochemical biosensor. However, a thermodynamic study that describes the adsorption processes of this type of assemble, has not been reported. Hence in this work, differential capacitance studies of Au/Cys, Au/SOD and Au/Cys/SOD electrodes are reported to describe the adsorption process during the different steps of the enzyme immobilization, through the calculation of charge density, surface tension, surface excess and adsorption energy. Theoretical electrostatic potential calculations of the protein using X-ray diffraction data were carried out, to rationalize the adsorption orientation of SOD according to experimental data.
By means of differential capacitance in this work we report a description of adsorption of SOD over Au electrodes using the cysteine as promoter. Electrostatic potential calculations of the protein were carried out, to rationalize the adsorption orientation of SOD.
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Tropical dry forests (TDF) are known to be resource‐limited due to a marked seasonality in precipitation. However, TDF are also shaped by factors such as solar radiation, wind speed, soil fertility, ...and land‐cover transformation. Together, these factors may determine different gradients of environmental harshness that are likely to drive changes in plant community attributes. Here, we evaluated the effects of environmental harshness on plant community diversity and structure of Colombian TDF, based on floristic and environmental data from 15 1‐ha permanent plots. We also analyzed these effects on legumes species only (including both deciduous and non‐deciduous species), deciduous species only (including both legumes and non‐legumes species), and on the whole community excluding either legumes or deciduous separately. Drier conditions and higher land‐cover transformation had the strongest negative effects on species diversity, basal area (BA), and canopy height. Soil fertility, on the contrary, did not have a significant effect on any of the evaluated response variables. Interestingly, legumes maintained their diversity and BA along the climatic gradient, while deciduous species were negatively affected by drier conditions and by an increase in secondary vegetation at the landscape level. Our results suggest that although TDF are limited by water availability, land‐cover transformation strongly increases environmental harshness. Yet, both legumes and deciduous species were differentially impacted by climatic and land transformation variables. Thus, to better understand TDF plant community attributes, it is necessary to consider these gradients and to disentangle their effects on different plant functional groups.
in Spanish is available with online material.
Resumen
Es ampliamente conocido que los bosques secos tropicales (BST) tienen fuertes limitaciones de recursos derivadas de estacionalidad de la precipitación. Sin embargo, otros factores como la radiación solar, la velocidad del viento, la fertilidad de los suelos y la transformación de las coberturas también dan forma a las condiciones ambientales restrictivas de este ecosistema. En conjunto, estos factores determinan la dureza ambiental que rige el BST y probablemente explican los cambios en los atributos comunitarios de las plantas a lo largo de gradientes. Evaluamos los efectos de la dureza ambiental sobre la diversidad de plantas y atributos estructurales del BST con base en datos florísticos y ambientales para 15 parcelas permanentes de 1 ha, para toda la comunidad de plantas, y subgrupos de plantas que incluyeron solo especies de leguminas y solo caducifolias por separado. Las condiciones secas y coberturas altamente transformadas tuvieron los efectos negativos sobre la diversidad de especies, el área basal y la altura del dosel a nivel comunitario, mientras que la fertilidad del suelo no afectó a ninguno de los atributos evaluados. Interesantemente, el grupo de especies leguminosas mantuvieron su diversidad y área basal a lo largo del gradiente de severidad climática, mientras que el grupo de especies de hoja caduca se vio negativamente afectado por las condiciones más secas y el aumento en el área de coberturas secundarias. Nuestros resultados sugieren que, aunque el BST esta claramente limitado por la disponibilidad del agua, la transformación de las coberturas naturales impulsa el aumento de la dureza ambiental en este ecosistema. Donde, las especies de leguminosas y caducifolias se ven afectadas de manera diferente a toda la comunidad de plantas. De tal forma, para un mejor entendimiento de como cambian los atributos comunitarios de las plantas en los BST es necesario tener en cuenta todas las fuentes de variación ambiental, así como, desagregar los efectos particulares para determinados grupos funcionales de plantas.
Palladium–graphene (PdGO) nanostructures with high-quality-graphene layers and well monodispersed palladium nanoparticles (PdNPs) were synthesized by the hydrothermal microwave exfoliation method. ...The structural and morphological characteristics of PdGO were investigated, and the results indicate that the hydrothermal-microwave method allows both the reduction of metal precursors and their anchorage on highly exfoliated graphene layers. The synthesized PdGO nanostructures were then deposited as active layers for sensing hydrogen gas (H
2
). PdGO-based sensors with gas concentrations from 0.01 to 5 vol% in air exhibited a very reproducible performance with fast response times (∼30 s) and recovery behavior at room temperature. Measurement of impedance response serves as a highly sensitive feasible sensor technique. Our results show that it is feasible to obtain an efficient H
2
-sensor with reliable and reproducible sensing properties by means of a simple and cost-effective preparation method under real atmospheric conditions.
Atypical presentations of denguevirus 3 in Veracruz, Mexico Del Carpio-Orantes, Luis; Trelles-Hernández, Daniela; López-Vargas, Ener René ...
Travel medicine and infectious disease,
2023 Nov-Dec, 2023-11-00, 20231101, 2023-11-01, Letnik:
56
Journal Article
Recenzirano
Odprti dostop
Dear editor Currently Mexico, as well as several Latin American countries, faces a dengue pandemic, reporting 34,189 cases of dengue as of epidemiological week 41 (October 16, 2023), with 88 deaths ...and a fatality rate of 0.57, highlighting some endemic regions such as Veracruz, where a significant percentage of cases is concentrated (7246 cases, second place nationally and 19 deaths); Regarding the surveillance of circulating serotypes, 2014 studies have been carried out in Veracruz, highlighting 1207 cases of DENV-2 and 497 cases of DENV-3; Lately, he has highlighted the atypical forms of clinical presentation where the typical febrile syndrome accompanied by arthralgia, headache and skin rash, among other symptoms, is not the current form of presentation, also highlighting that although there is circulation of the 4 known serotypes and that it is always DENV-2 that predominates, this year we are seeing a greater prevalence of DENV-3 cases, which probably explains the current clinical symptoms that have stood out for greater liver involvement, as well as respiratory symptoms that simulate COVID or other respiratory viruses, likewise the endothelial involvement has been minimal, presenting cases with normal or slightly decreased platelet counts, something very atypical of dengue in this region of southeastern Mexico (Table 1) 1. The present outbreak is probably related to the outbreaks reported in the Caribbean and Brazil and, together with the atypical nature of its clinical features, forces us to maintain strict epidemiological surveillance, as well as to improve and implement action guidelines for dengue to reduce the risk. Morbidity and mortality due to this cause, coupled with the fact that coinfections may be evident in pandemic times.Declaration of competing interest None Genre/Age Clinical or biochemical presentation Serology Serotipes Female/28 yo Respiratory chart Thrombocytopenia NS1 positive DENV-3 IgM positive Influenza negative COVID negative Male/33 yo Respiratory chart normal platelets NS1 positive DENV-3 Influenza negative COVID negative Female/40 yo Respiratory chart Mild thrombocytopenia (day 7) NS1 positive DENV-3 Influenza negative COVID negative Male/45 yo Acute hepatitis thrombocytopenia Febrile syndrome NS1 positive DENV-3 Hepatitis B and C negative Ultrasound: liver disease Female/28 yo Acute hepatitis thrombocytopenia Febrile syndrome NS1 positive DENV-3 IgM positive Hepatitis A, B and C negative Female/28 yo Acute hepatitis thrombocytopenia Febrile syndrome Severe arthralgias NS1 positive DENV-3 Hepatitis A, B and C negative Male/35 yo Acute hepatitis normal platelets Febrile syndrome NS1 positive DENV-3 Hepatitis A, B and C negative Ultrasound: liver disease Table 1 Atypical cases associated with Dengue virus 3.
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