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Methane (CH4) display spectral features in several regions of the infrared range (0.75–14 µm), which can be used for the remote mapping of emission sources through the detection of CH4 plumes from natural seeps and leaks. Applications of hyperspectral remote sensing techniques for the detection of CH4 in the near and shortwave infrared (NIR-SWIR: 0.75–3 µm) and longwave infrared (LWIR: 7–14 µm) have been demonstrated in the literature with multiple sensors and scenarios. However, the acquisition and processing of hyperspectral data in the midwave infrared (MWIR: 3–5 µm) for this application is rather scarce. Here, a controlled field experiment was used to evaluate the potential for CH4 plume detection in the MWIR based on hyperspectral data acquired with the SEBASS airborne sensor. For comparison purposes, LWIR data were also acquired simultaneously with the same instrument. The experiment included surface and undersurface emission sources (ground stations), with flow rates ranging between 0.6–40 m3/h. The data collected in both ranges were sequentially processed using the same methodology. The CH4 plume was detected, variably, in both datasets. The gas plume was detected in all LWIR images acquired over nine gas leakage stations. In the MWIR range, the plume was detected in only four stations, wherein 18 m3/h was the lowest flux sensed. We demonstrate that the interference of target reflectance, the low contrast between plume and background and a low signal of the CH4 feature in the MWIR at ambient conditions possibly explain the inferior results observed for this range when compared to LWIR. Furthermore, we show that the acquisition time and weather conditions, including specific limits of temperature, humidity, and wind speed, proved critical for plume detection using daytime MWIR hyperspectral data.

Leaks from accidents or damage to pipelines that transport liquid petroleum hydrocarbons (PHC) such as gasoline and diesel are harmful to the environment as well as to human health, and may be hard to detect by inspection mechanisms alone when they occur in small volumes or persistently. In the present study, we aim to identify spectral anomalies in two plant species (Brachiaria brizantha and Neonotonia wightii) linked to contamination effects at different developmental phases of these plants. To do so, we used spectroscopy and remote sensing approaches to detect small gasoline and diesel leaks by observing the damage caused to the vegetation that covers simulated pipelines. We performed a contamination test before and after planting using gasoline and diesel volumes that varied between 2 and 16 L/m3 soil, in two experimental designs: (i) single contamination before planting, and (ii) periodic contaminations after planting and during plant growth. We collected the reflectance spectra from 35 to approximately 100 days after planting. We then compared the absorption features positioned from the visible spectral range to the shortwave infrared and the spectral parameters in the red edge range of the contaminated plants to the healthy plants, thus confirming the visual and biochemical changes verified in the contaminated plants. Despite the complexity in the indirect identification of soil contamination by PHCs, since it involves different stages of plant development, the results were promising and can be used as a reference for methods of indirect detection from UAVs (Unmanned Aerial Vehicles), airplanes, and satellites equipped with hyperspectral sensors.

As of 16 May 2020, the number of confirmed cases and deaths in Brazil due to COVID-19 hit 233,142 and 15,633, respectively, making the country one of the most affected by the pandemic. The State of São Paulo (SSP) hosts the largest number of confirmed cases in Brazil, with over 60,000 cases to date. Here we investigate the spatial distribution and spreading patterns of COVID-19 in the SSP by mapping the spatial autocorrelation and the clustering patterns of the virus in relation to the population density and the number of hospital beds. Clustering analysis indicated that São Paulo City is a significant hotspot for both the confirmed cases and deaths, whereas other cities across the state were less affected. Bivariate Moran’s I showed a low relationship between the number of deaths and population density, whereas the number of hospital beds was less related, implying that the fatality depends substantially on the actual patients’ conditions. Multivariate Local Geary showed a positive relationship between the number of deaths and population density, with two cities near São Paulo City being negatively related; the relationship between the number of deaths and hospital beds availability in the São Paulo Metropolitan Area was basically positive. Social isolation measures throughout the State of São Paulo have been gradually increasing since early March, an action that helped to slow down the emergence of the new confirmed cases, highlighting the importance of the safe-distancing measures in mitigating the local transmission within and between cities in the state.

Mangroves are among the most ecologically valuable ecosystems of the globe. Reliable remote sensing solutions are required to assist their management and conservation at broad scale. Canopy gaps are part of forests' turnover and rejuvenation, but yet no method has been proposed to map their occurrence and recovery in mangroves. Here, were propose an approach based on a deep learning framework called Mask R‐CNN to achieve automatic detection and delineation of gaps using very‐high‐resolution satellite imagery (<1 m). The Mask R‐CNN combines a series of neural network architectures to identify and delineate gaps, determine their recovery stage, and estimate their morphological attributes. The approach was tested on four mangroves from different regions of the globe with high concentration of gaps of various origins (lightning strikes, oil spills, cutting, pests). The Mask R‐CNN performed well to detect gaps, and accurately delineated gap contours (F1‐score of segmentation ≥0.89). The model also succeeded in distinguishing among five recovery stages of gaps, from their onset to closure (Overall Accuracy = 91.4, Kappa = 0.89). Accurate retrieval of gap area, eccentricity, and compactness – three relevant morphological attributes – were obtained (R2 ≥ 0.83, NRMSE ≤10%). Several sources of confusion and misdelineation were identified. Our approach shows promising transferability to other mangrove sites and optical sensors and could help monitor canopy recovery in mangroves. It also opens promising perspectives for identifying the origin of gaps (natural or human‐induced). It is intended to assist environmental managers and field experts in the management and conservation of these fragile ecosystems. Canopy gaps greatly contribute to mangrove forest turnover and rejuvenation. While gap monitoring is usually performed by field and aerial surveys, we propose a novel method based on deep learning to achieve this automatically from very‐high‐resolution satellite imagery. A multi‐task neural network is applied to the images to accurately detect and delineate gaps, and to determine their recovery stage. Our method proved reliable in various forests of the globe with contrasting characteristics and could therefore improve mangrove conservation and monitoring. Our study also opens perspectives to identify the origin of gaps, including those caused by human activities.

Purpose: To perform a systematic review and meta-analysis comparing the efficacy of botulinum toxin A (BTX-A) and bilateral medial rectus recession (BMR) surgery for partially accommodative esotropia (PAET). Methods: PubMed, EMBASE, and the Cochrane database were searched on May 29, 2024 for studies comparing BTX-A and BMR in patients with PAET, reporting at least one outcome of interest. The odds ratio (OR) and 95% CI were used for binary outcomes. Heterogeneity was assessed using I2 statistics. The analysis was performed using R software version 4.3.2. The Risk of Bias Summary for Non-randomized Studies tool was used to assess the risk of bias. Results: Four observational studies comprising 521 patients were eligible for inclusion. BTX-A and BMR groups had comparable motor success rates (OR: 1.14; 95% CI: 0.27 to 4.81; P = .861; I2 = 88%). However, consecutive exotropia was reported exclusively after BMR only (OR: 0.08; 95% CI: 0.01 to 0.46; P = .004; I2 = 0%). All studies accounted for heterogeneity in the leave-one-out sensitivity analysis. Two studies were judged as moderate risk of bias and two as serious. Assessment of Grading of Recommendations Assessment Development and Evaluation resulted in moderate certainty in the outcome of motor success rates. Conclusions: BTX-A might be a good alternative to BMR in patients with PAET. Randomized controlled trials with larger sample sizes and longer duration of follow-up are needed. Studies should also focus on sensory outcomes in addition to motor outcomes.

Enterobacter cloacae is a Gram-negative bacterium associated with high morbidity and mortality in intensive care patients due to its resistance to multiple antibiotics. Currently, therapy against multi-resistant bacteria consists of using colistin, in spite of its toxic effects at higher concentrations. In this context, colistin-resistant E. cloacae strains were challenged with lower levels of colistin combined with other antibiotics to reduce colistin-associated side effects. Colistin-resistant E. cloacae (ATCC 49141) strains were generated by serial propagation in subinhibitory colistin concentrations. After this, three colistin-resistant and three nonresistant replicates were isolated. The identity of all the strains was confirmed by MALDI-TOF MS, VITEK 2 and MicroScan analysis. Furthermore, cross-resistance to other antibiotics was checked by disk diffusion and automated systems. The synergistic effects of the combined use of colistin and chloramphenicol were observed via the broth microdilution checkerboard method. First, data here reported showed that all strains presented intrinsic resistance to penicillin, cephalosporin (except fourth generation), monobactam, and some associations of penicillin and β-lactamase inhibitors. Moreover, a chloramphenicol and colistin combination was capable of inhibiting the induced colistin-resistant strains as well as two colistin-resistant clinical strains. Furthermore, no cytotoxic effect was observed by using such concentrations. In summary, the data reported here showed for the first time the possible therapeutic use of colistin–chloramphenicol for infections caused by colistin-resistant E. cloacae .

The Bacaba iron oxide–copper–gold deposit, situated within a WNW–ESE-striking shear zone in the Carajás Domain, Carajás Mineral Province, is hosted by the Serra Dourada Granite, the Bacaba Tonalite, and crosscutting gabbro intrusions, which were intensely affected by sodic (albite–scapolite), potassic, chloritic, and hydrolytic hydrothermal alteration. This deposit is located 7 km northeast of the world-class Sossego iron oxide–copper–gold deposit and might represent a distal and deeper portion of the same or related hydrothermal system. The U–Pb laser ablation inductively coupled plasma–mass spectrometry data for zircon from a sodically altered sample of the Serra Dourada Granite yielded a 2,860±22 Ma (MSWD=11.5) age. Three samples from the Bacaba Tonalite, including one with potassic alteration and two with Cu–Au mineralization, rendered the 3,001.2±3.6 Ma (MSWD=1.8), 2,990.9±5.8 Ma (MSWD=1.9), and 3,004.6±9 Ma (MSWD=2.2) ages, respectively. The ca. 2.86 and ca. 3.0 Ga ages are interpreted as the timing of the igneous crystallization of the Serra Dourada Granite and the Bacaba Tonalite, respectively, and represent the oldest magmatic events recognized in the Carajás Domain. The Serra Dourada Granite and the Bacaba Tonalite are interpreted to greatly predate the genesis of the Bacaba deposit. A genetic link is improbable in the light of the similarities with the Sossego deposit, which is also hosted by younger ca. 2.76 Ga metavolcano-sedimentary units of the Itacaiúnas Supergroup. In this context, the iron oxide–copper–gold deposits in the southern sector of the Carajás Domain could be mainly controlled by important crustal discontinuities, such as a regional shear zone, rather than be associated with a particular rock type. These results expand the potential for occurrences of iron oxide–copper–gold deposits within the Mesoarchean basement rocks underlying the Carajás Basin, particularly those crosscut by Neoarchean shear zones.

The environmental conditions on the Earth before 4 billion years ago are highly uncertain, largely because of the lack of a substantial rock record from this period. During this time interval, known as the Hadean, the young planet transformed from an uninhabited world to the one capable of supporting, and inhabited by the first living cells. These cells formed in a fluid environment they could not at first control, with homeostatic mechanisms developing only later. It is therefore possible that present-day organisms retain some record of the primordial fluid in which the first cells formed. Here we present new data on the elemental compositions and mineral fingerprints of both Bacteria and Archaea, using these data to constrain the environment in which life formed. The cradle solution that produced this elemental signature was saturated in barite, sphene, chalcedony, apatite, and clay minerals. The presence of these minerals, as well as other chemical features, suggests that the cradle environment of life may have been a weathering fluid interacting with dry-land silicate rocks. The specific mineral assemblage provides evidence for a moderate Hadean climate with dry and wet seasons and a lower atmospheric abundance of CO 2 than is present today.

On 15 February 2022, the city of Petrópolis in the highlands of the state of Rio de Janeiro, Brazil, received an unusually high volume of rain within 3 h (258 mm), generated by a strongly invigorated mesoscale convective system. It resulted in flash floods and subsequent landslides that caused the deadliest landslide disaster recorded in Petrópolis, with 231 fatalities. In this paper, we analyzed the root causes and the key triggering factors of this landslide disaster by assessing the spatial relationship of landslide occurrence with various environmental factors. Rainfall data were retrieved from 1977 to 2022 (a combination of ground weather stations and the Climate Hazards Group InfraRed Precipitation – CHIRPS). Remotely sensed data were used to map the landslide scars, soil moisture, terrain attributes, line-of-sight displacement (land surface deformation), and urban sprawling (1985–2020). The results showed that the average monthly rainfall for February 2022 was 200 mm, the heaviest recorded in Petrópolis since 1932. Heavy rainfall was also recorded mostly in regions where the landslide occurred, according to analyses of the rainfall spatial distribution. As for terrain, 23 % of slopes between 45–60∘ had landslide occurrences and east-facing slopes appeared to be the most conducive for landslides as they recorded landslide occurrences of about 9 % to 11 %. Regarding the soil moisture, higher variability was found in the lower altitude (842 m) where the residential area is concentrated. Based on our land deformation assessment, the area is geologically stable, and the landslide occurred only in the thin layer at the surface. Out of the 1700 buildings found in the region of interest, 1021 are on the slope between 20 to 45∘ and about 60 houses were directly affected by the landslides. As such, we conclude that the heavy rainfall was not the only cause responsible for the catastrophic event of 15 February 2022; a combination of unplanned urban growth on slopes between 45–60∘, removal of vegetation, and the absence of inspection were also expressive driving forces of this disaster.

The Sossego iron oxide–copper–gold deposit (245 Mt @ 1.1% Cu, 0.28 g/t Au) in the Carajás Mineral Province of Brazil consists of two major groups of orebodies (Pista–Sequeirinho–Baiano and Sossego–Curral) with distinct alteration assemblages that are separated from each other by a major high angle fault. The deposit is located along a regional WNW–ESE-striking shear zone that defines the contact between metavolcano–sedimentary units of the ∼2.76 Ga Itacaiúnas Supergroup and tonalitic to trondhjemitic gneisses and migmatites of the ∼2.8 Ga Xingu Complex. The deposit is hosted by granite, granophyric granite, gabbro, and felsic metavolcanic rocks. The Pista–Sequeirinho–Baiano orebodies have undergone regional sodic (albite–hematite) alteration and later sodic–calcic (actinolite-rich) alteration associated with the formation of massive magnetite–(apatite) bodies. Both these alteration assemblages display ductile to ductile–brittle fabrics. They are cut by spatially restricted zones of potassic (biotite and potassium feldspar) alteration that grades outward to chlorite-rich assemblages. The Sossego–Curral orebodies contain weakly developed early albitic alteration and very poorly developed subsequent calcic–sodic alteration. These orebodies contain well-developed potassic alteration assemblages that were formed during brittle deformation that resulted in the formation of breccia bodies. Breccia matrix commonly displays coarse mineral infill suggestive of growth into open space. Sulfides in both groups of deposits were precipitated first with potassic alteration and more importantly with a later assemblage of calcite–quartz–epidote–chlorite. In the Sequeirinho orebodies, sulfides range from undeformed to deformed; sulfides in the Sossego–Curral orebodies are undeformed. Very late, weakly mineralized hydrolytic alteration is present in the Sossego/Currral orebodies. The sulfide assemblage is dominated by chalcopyrite with subsidiary siegenite, and millerite. Pyrrhotite and pyrite are minor constituents of ore in the Sequerinho orebodies while pyrite is relatively abundant in the Sossego–Curral bodies. Oxygen isotope partitioning between mineral pairs constrains temperatures in the deposit spatially and through time. In the Sequeirinho orebody, the early sodic–calcic alteration stage was characterized by temperatures exceeding 500°C and values for the alteration fluid of 6.9 ± 0.9‰. Temperature declines outward and upward from the zone of most intense alteration. Paragenetically later copper–gold mineralization displays markedly lower temperatures (<300°C) and was characterized by the introduction of 18 O-depleted hydrothermal fluids −1.8 ± 3.4‰. The calculated δD H2O and values suggest that the fluids that formed the early calcic–sodic alteration assemblage were of formational/metamorphic or magmatic origin. The decrease of values through time may reflect influx of surficially derived waters during later alteration and mineralization events. Influx of such fluids could be related to episodic fluid overpressure, resulting in dilution and cooling of the metalliferous fluid, causing deposition of metals transported as metal chloride complexes.