Sporadic E (Es) layers are patches of high ionization observed at
around 100–140 km height in the E region. Their formation at low latitudes
is primarily associated with the diurnal and semidiurnal ...components of the
tidal winds via the ion convergence driven by the wind shear mechanism.
However, recent studies have shown the influence of other tidal modes, such
as the terdiurnal tide. Therefore, this work investigates the effect of
terdiurnal tide-like oscillations on the occurrence and formation of the Es layers
observed over Palmas (10.17∘ S, 48.33∘ W; dip lat.
−7.31∘), a low-latitude station in Brazil. The analysis was
conducted from December 2008 to November 2009 by using data collected from
CADI (Canadian Advanced Digital Ionosonde). Additionally, the E
Region Ionospheric Model (MIRE) was used to simulate the terdiurnal tidal
component in the Es layer development. The results show modulations of 8 h
periods on the occurrence rates of the Es layers during all seasonal periods.
In general, we see three well-defined peaks in a superimposed summation of
the Es layer types per hour in summer and autumn. We also observed that the
amplitude modulation of the terdiurnal tide on the Es occurrence rates
minimizes in December in comparison to the other months of the summer
season. Other relevant aspects of the observations, with complementary
statistical and periodogram analysis, are highlighted and discussed.
We report here methods and techniques for creating an improved model that reproduces the scintillation and ionization response of a dual-phase liquid and gaseous xenon time projection chamber. ...Starting with the recent release of the Noble Element Simulation Technique (NEST v2.0), electronic recoil data from the β decays of 3H and 14C in the Large Underground Xenon (LUX) detector were used to tune the model, in addition to external data sets that allow for extrapolation beyond the LUX data-taking conditions. This paper also presents techniques used for modeling complicated temporal and spatial detector pathologies that can adversely affect data using a simplified model framework. The methods outlined in this report show an example of the robust applications possible with NEST v2.0 framework and how it can be modified to produce a final, detector-specific, electronic recoil model. This example provides the final model for LUX and detector parameters that will used in the new analysis package, the LUX Legacy Analysis Monte Carlo Application (LLAMA), for accurate reproduction of the LUX data. As accurate background reproduction is crucial for the success of rare-event searches, such as dark matter direct detection experiments, the techniques outlined here can be used in other single-phase and dual-phase xenon detectors to assist with accurate ER background reproduction.
The Amazon rainforest is the world's largest source of reactive volatile isoprenoids to the atmosphere. It is generally assumed that these emissions are products of photosynthetically driven ...secondary metabolism and released from the rainforest canopy from where they influence the oxidative capacity of the atmosphere. However, recent measurements indicate that further sources of volatiles are present. Here we show that soil microorganisms are a strong, unaccounted source of highly reactive and previously unreported sesquiterpenes (C
H
; SQT). The emission rate and chemical speciation of soil SQTs were determined as a function of soil moisture, oxygen, and rRNA transcript abundance in the laboratory. Based on these results, a model was developed to predict soil-atmosphere SQT fluxes. It was found SQT emissions from a Terra Firme soil in the dry season were in comparable magnitude to current global model canopy emissions, establishing an important ecological connection between soil microbes and atmospherically relevant SQTs.
Cancer-associated fibroblasts (CAFs) are molecularly heterogeneous mesenchymal cells that interact with malignant cells and immune cells and confer anti- and protumorigenic functions. Prior in situ ...profiling studies of human CAFs have largely relied on scoring single markers, thus presenting a limited view of their molecular complexity. Our objective was to study the complex spatial tumor microenvironment of non-small cell lung cancer (NSCLC) with multiple CAF biomarkers, identify novel CAF subsets, and explore their associations with patient outcome.
Multiplex fluorescence immunohistochemistry was employed to spatially profile the CAF landscape in 2 population-based NSCLC cohorts (n = 636) using antibodies against 4 fibroblast markers: platelet-derived growth factor receptor-alpha (PDGFRA) and -beta (PDGFRB), fibroblast activation protein (FAP), and alpha-smooth muscle actin (αSMA). The CAF subsets were analyzed for their correlations with mutations, immune characteristics, and clinical variables as well as overall survival.
Two CAF subsets, CAF7 (PDGFRA-/PDGFRB+/FAP+/αSMA+) and CAF13 (PDGFRA+/PDGFRB+/FAP-/αSMA+), showed statistically significant but opposite associations with tumor histology, driver mutations (tumor protein p53 TP53 and epidermal growth factor receptor EGFR), immune features (programmed death-ligand 1 and CD163), and prognosis. In patients with early stage tumors (pathological tumor-node-metastasis IA-IB), CAF7 and CAF13 acted as independent prognostic factors.
Multimarker-defined CAF subsets were identified through high-content spatial profiling. The robust associations of CAFs with driver mutations, immune features, and outcome suggest CAFs as essential factors in NSCLC progression and warrant further studies to explore their potential as biomarkers or therapeutic targets. This study also highlights multiplex fluorescence immunohistochemistry-based CAF profiling as a powerful tool for the discovery of clinically relevant CAF subsets.
Raman spectroscopy is highly sensitive to the morphology and electronic structures of graphitic materials, but a convenient interpretation model has been lacking for multiwalled carbon nanotubes ...(MWCNTs), in particular for the discrimination of spectral changes induced by covalent functionalization. The present work describes a systematic investigation of the Raman analysis of covalently functionalized MWCNTs by diazonium chemistry and oxidation methodologies, with typically different mechanisms and reaction sites. A multi-peak deconvolution system and spectral band assignment were proposed based on the chemical and structural modifications identified by X-ray photoelectron spectroscopy, thermogravimetry, X-ray diffraction, specific surface areas and the comparative analysis of the first and second order regions of the Raman spectra. Diazonium functionalization takes place mainly in the π-system of the external sidewall, while oxidation occurs on defects and leads to structure burning. This allowed us to distinguish between spectral features related to aromaticity disruptions within the sidewalls and spectral features related to changes within the inner tubes. The model was validated extending the studies to the functionalization of MWCNTs by the Bingel reaction.
Carbon fiber composites (CFC) are being widely used in the aircraft industry due to their excellent properties. Its low weight, better resistance to corrosion and fatigue, are one of the advantages ...compared to metals such as aluminum. With the increasing use of CFC in aircraft, studies on the effects of lightning strikes on these materials are extremely important. The study of the indirect effects caused by an atmospheric discharge concerns the effects of the current conduction through the fuselage of an aircraft. In this study, lightning strikes are simulated when applied to the CFC and the indirect effects caused by the conduction of the current are analyzed.
The application of thermophilic anaerobic digestion is a logical choice for the treatment of sugarcane vinasse (industrial wastewater from ethanol production) because this process enables the ...recovery of energy as hydrogen and methane without requiring energy for heat or interfering in its quality as a bio-fertilizer. Thus, this study evaluated the performance of thermophilic methanogenic up-flow sludge blanket reactors (UASB) operating continuously in single-stage (UASB I) and two-stage (UASB II) systems vinasse during the sugarcane harvesting season (180 days). The maximum methane yields were 250.9 NmL-CH4.g−1CODremoved and 316.0 NmL-CH4.g−1CODremoved for UASB I and II, respectively, corresponding to 71.7% and 90.3% of the maximum theoretical methane yield (350 NmL-CH4.g−1CODremoved). Furthermore, the energy production from the two-stage system was 25.7% higher than the single-stage system, indicating the need for an acidogenic phase to improve both the removal of organic matter and energy extraction from sugarcane vinasse.
•Anaerobic digestion of vinasse was evaluated during a sugarcane harvesting season.•Single and two-stage systems were used for sugarcane vinasse treatment.•A methane yield of 306 NmL-CH4.g-CODremoved was achieved with the two-stage system.•The energy yield increased by 25.7% using two-stage anaerobic digestion.•Effluent propionate concentrations was independent of OLR increase.
A classification for peri‐implant diseases and conditions was presented. Focused questions on the characteristics of peri‐implant health, peri‐implant mucositis, peri‐implantitis, and soft‐ and ...hard‐tissue deficiencies were addressed.
Peri‐implant health is characterized by the absence of erythema, bleeding on probing, swelling, and suppuration. It is not possible to define a range of probing depths compatible with health; Peri‐implant health can exist around implants with reduced bone support.
The main clinical characteristic of peri‐implant mucositis is bleeding on gentle probing. Erythema, swelling, and/or suppuration may also be present. An increase in probing depth is often observed in the presence of peri‐implant mucositis due to swelling or decrease in probing resistance. There is strong evidence from animal and human experimental studies that plaque is the etiological factor for peri‐implant mucositis.
Peri‐implantitis is a plaque‐associated pathological condition occurring in tissues around dental implants, characterized by inflammation in the peri‐implant mucosa and subsequent progressive loss of supporting bone. Peri‐implantitis sites exhibit clinical signs of inflammation, bleeding on probing, and/or suppuration, increased probing depths and/or recession of the mucosal margin in addition to radiographic bone loss.
The evidence is equivocal regarding the effect of keratinized mucosa on the long‐term health of the peri‐implant tissue. It appears, however, that keratinized mucosa may have advantages regarding patient comfort and ease of plaque removal.
Case definitions in day‐to‐day clinical practice and in epidemiological or disease‐surveillance studies for peri‐implant health, peri‐implant mucositis, and peri‐implantitis were introduced. The proposed case definitions should be viewed within the context that there is no generic implant and that there are numerous implant designs with different surface characteristics, surgical and loading protocols. It is recommended that the clinician obtain baseline radiographic and probing measurements following the completion of the implant‐supported prosthesis.
Interactions between species are influenced by different ecological mechanisms, such as morphological matching, phenological overlap and species abundances. How these mechanisms explain interaction ...frequencies across environmental gradients remains poorly understood. Consequently, we also know little about the mechanisms that drive the geographical patterns in network structure, such as complementary specialization and modularity. Here, we use data on morphologies, phenologies and abundances to explain interaction frequencies between hummingbirds and plants at a large geographical scale. For 24 quantitative networks sampled throughout the Americas, we found that the tendency of species to interact with morphologically matching partners contributed to specialized and modular network structures. Morphological matching best explained interaction frequencies in networks found closer to the equator and in areas with low-temperature seasonality. When comparing the three ecological mechanisms within networks, we found that both morphological matching and phenological overlap generally outperformed abundances in the explanation of interaction frequencies. Together, these findings provide insights into the ecological mechanisms that underlie geographical patterns in resource specialization. Notably, our results highlight morphological constraints on interactions as a potential explanation for increasing resource specialization towards lower latitudes.
•Synthesis of a new photocatalyst material based on α-Fe2O3 fibers by Solution Blow Spinning (SBS) method.•α-Fe2O3 fibers showed high degradation efficiency of methylene blue and crystal violet dyes ...under visible light.•The photocatalytic mechanism of α-Fe2O3 fibers has been revealed and the samples also show good recyclability results.
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In this work, α-Fe2O3 fibers were successfully prepared via Solution Blow Spinning, followed by calcination at 800 °C for 2 h, and applied in the photodegradation of organic dyes. The precursor solution was prepared by dissolving 0.8 M iron nitrate and 12 w/v% PVP in an acetic acid/water (2:1) mixture. The as-synthesized nanostructures were characterized by scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) isothermal model, x-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (DRS), Mössbauer spectroscopy and magnetometry. The studies of photocatalytic degradation were performed using methylene blue (MB) and crystal violet (CV) dyes under visible and UV irradiation. The results indicated the formation of α-Fe2O3 fibers with a trigonal crystalline structure with an average diameter and BET surface area of 359 nm and 2.54 m2/g, respectively. The fibers showed a photodegradation efficiency of 66% and 48% for MB dye and 90% and 92% for the CV dye after 5 h of visible and ultraviolet light irradiation, respectively. The recycling studies indicated stability and efficiency after three cycles of degradation of the CV dye.
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