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1.
Eur J Surg Oncol ; 50(6): 108050, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38498966

RESUMO

BACKGROUND: Isolated limb perfusion (ILP) is a well-established surgical procedure for the administration of high dose chemotherapy to a limb for the treatment of advanced extremity malignancy. Although the technique of ILP was first described over 60 years ago, ILP is utilised in relatively few specialist centres, co-located with tertiary or quaternary cancer centres. The combination of high dose cytotoxic chemotherapy and the cytokine tumour necrosis factor alpha (TNFα), mandates leakage monitoring to prevent potentially serious systemic toxicity. Since the procedure is performed at relatively few specialist centres, an ILP working group was formed with the aim of producing technical consensus guidelines for the procedure to streamline practice and to provide guidance for new centres commencing the technique. METHODS: Between October 2021 and October 2023 a series of face to face online and hybrid meetings were held in which a modified Delphi process was used to develop a unified consensus document. After each meeting the document was modified and recirculated and then rediscussed at subsequent meeting until a greater than 90% consensus was achieved in all recommendations. RESULTS: The completed consensus document comprised 23 topics in which greater than 90% consensus was achieved, with 83% of recommendations having 100% consensus across all members of the working group. The consensus recommendations covered all areas of the surgical procedure including pre-operative assessment, drug dosing and administration, perfusion parameters, hyperthermia, leakage monitoring and theatre logistics, practical surgical strategies and also post-operative care, response evaluation and staff training. CONCLUSION: We present the first joint expert-based consensus statement with respect to the technical aspects of ILP that can serve as a reference point for both existing and new centres in providing ILP.

2.
Nat Commun ; 15(1): 2224, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472196

RESUMO

Climate change impact syntheses, such as those by the Intergovernmental Panel on Climate Change, consistently assert that limiting global warming to 1.5 °C is unlikely to safeguard most of the world's coral reefs. This prognosis is primarily based on a small subset of available models that apply similar 'excess heat' threshold methodologies. Our systematic review of 79 articles projecting coral reef responses to climate change revealed five main methods. 'Excess heat' models constituted one third (32%) of all studies but attracted a disproportionate share (68%) of citations in the field. Most methods relied on deterministic cause-and-effect rules rather than probabilistic relationships, impeding the field's ability to estimate uncertainty. To synthesize the available projections, we aimed to identify models with comparable outputs. However, divergent choices in model outputs and scenarios limited the analysis to a fraction of available studies. We found substantial discrepancies in the projected impacts, indicating that the subset of articles serving as a basis for climate change syntheses may project more severe consequences than other studies and methodologies. Drawing on insights from other fields, we propose methods to incorporate uncertainty into deterministic modeling approaches and propose a multi-model ensemble approach to generating probabilistic projections for coral reef futures.


Assuntos
Antozoários , Recifes de Corais , Animais , Mudança Climática , Antozoários/fisiologia , Incerteza , Aquecimento Global , Ecossistema
3.
ISME Commun ; 4(1): ycae015, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38456147

RESUMO

A persistent microbial seed bank is postulated to sustain the marine biosphere, and recent findings show that prokaryotic taxa present in the ocean's surface dominate prokaryotic communities throughout the water column. Yet, environmental conditions exert a tight control on the activity of prokaryotes, and drastic changes in these conditions are known to occur from the surface to deep waters. The simultaneous characterization of the total (DNA) and active (i.e. with potential for protein synthesis, RNA) free-living communities in 13 stations distributed across the tropical and subtropical global ocean allowed us to assess their change in structure and diversity along the water column. We observed that active communities were surprisingly more similar along the vertical gradient than total communities. Looking at the vertical connectivity of the active vs. the total communities, we found that taxa detected in the surface sometimes accounted for more than 75% of the active microbiome of bathypelagic waters (50% on average). These active taxa were generally rare in the surface, representing a small fraction of all the surface taxa. Our findings show that the drastic vertical change in environmental conditions leads to the inactivation and disappearance of a large proportion of surface taxa, but some surface-rare taxa remain active (or with potential for protein synthesis) and dominate the bathypelagic active microbiome.

4.
Mar Pollut Bull ; 201: 116264, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38492266

RESUMO

Plastic debris accumulating on beaches pose a major threat to marine ecosystems. Unexpected events affecting human operations, such as the COVID-19 pandemic, which prompted governments to implement safety measures and restrictions, can serve as an unplanned investigation of anthropogenic pressure on the marine environment. This study aimed to explore deviations in macroplastic delivery rates to the central eastern Red Sea shoreline during three distinct population mobility periods: before, during, and after COVID-19 restrictions, spanning from January 2019 to June 2022. We observed a 50 % reduction in the estimated macroplastic delivery rates during the lockdown, followed by a 25 % increase after restrictions were eased. Seasonal variations in delivery rates were also observed, with higher values during the winter monsoon. Reduced shoreline litter delivery during the pandemic highlights human operations as a cause of macroplastic litter and suggests the potential of temporary measures to reduce plastic pollution in the coastal environment.


Assuntos
COVID-19 , Resíduos , Humanos , Resíduos/análise , Ecossistema , Oceano Índico , Pandemias , Monitoramento Ambiental , Plásticos , Praias , Controle de Doenças Transmissíveis
5.
Water Res ; 252: 121192, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38309066

RESUMO

Samples from a dairy cattle waste-fed anaerobic digester were collected across seasons to assess sanitary safety for biofertilizer use. Isolated enterobacteria (suggestive of Escherichia coli) were tested for susceptibility to biocides, antimicrobials, and biofilm-forming capability. Results revealed a decrease in total bacteria, coliforms, and enterobacteria in biofertilizer compared to the effluent. Among 488 isolates, 98.12 % exhibited high biofilm formation. Biofertilizer isolates exhibited a similar biofilm formation capability as effluent isolates in summer, but greater propensity in winter. Resistance to biocides and antimicrobials varied, with tetracycline resistance reaching 19 %. Of the isolates, 25 were multidrug-resistant (MDR), with 64 % resistant to three drugs. Positive correlations were observed between MDR and increased biofilm formation capacity in both samples, while there was negative correlation between MDR and increased biocide resistance. A higher number of MDR bacteria were found in biofertilizer compared to the effluent, revealing the persistence of E. coli resistance, posing challenges to food safety and public health.


Assuntos
Anti-Infecciosos , Desinfetantes , Saúde Única , Animais , Bovinos , Escherichia coli , Enterobacteriaceae , Virulência , Anaerobiose , Águas Residuárias , Antibacterianos , Desinfetantes/farmacologia , Testes de Sensibilidade Microbiana
6.
Chem Biodivers ; 21(4): e202400235, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38412304

RESUMO

Over the last decades, soft corals have been proven a rich source of biologically active compounds, featuring a wide range of chemical structures. Herein, we investigated the chemistry of an alcyonarian of the genus Lemnalia (Neptheidae), specimens of which were collected from the coral reefs near Al Lith, on the south-west coast of Saudi Arabia. A series of chromatographic separations led to the isolation of 31 sesquiterpenes, featuring mainly the nardosinane and neolemnane carbon skeletons, among which three (13, 14 and 28) are new natural products. The metabolites isolated in sufficient amounts were evaluated in vitro in human tumor and non-cancerous cell lines for a number of biological activities, including their cytotoxic, anti-inflammatory, anti-angiogenic, and neuroprotective activities, as well as for their effect on androgen receptor (AR)-regulated transcription. Among the tested metabolites, compound 12 showed comparable neuroprotective activity to the positive control N-acetylcysteine, albeit at a 10-fold lower concentration.


Assuntos
Antozoários , Antineoplásicos , Sesquiterpenos , Animais , Humanos , Arábia Saudita , Oceano Índico , Sesquiterpenos/química , Antozoários/química , Antineoplásicos/farmacologia , Antineoplásicos/metabolismo
7.
Sci Data ; 11(1): 154, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302528

RESUMO

The Ocean microbiome has a crucial role in Earth's biogeochemical cycles. During the last decade, global cruises such as Tara Oceans and the Malaspina Expedition have expanded our understanding of the diversity and genetic repertoire of marine microbes. Nevertheless, there are still knowledge gaps regarding their diversity patterns throughout depth gradients ranging from the surface to the deep ocean. Here we present a dataset of 76 microbial metagenomes (MProfile) of the picoplankton size fraction (0.2-3.0 µm) collected in 11 vertical profiles covering contrasting ocean regions sampled during the Malaspina Expedition circumnavigation (7 depths, from surface to 4,000 m deep). The MProfile dataset produced 1.66 Tbp of raw DNA sequences from which we derived: 17.4 million genes clustered at 95% sequence similarity (M-GeneDB-VP), 2,672 metagenome-assembled genomes (MAGs) of Archaea and Bacteria (Malaspina-VP-MAGs), and over 100,000 viral genomic sequences. This dataset will be a valuable resource for exploring the functional and taxonomic connectivity between the photic and bathypelagic tropical and sub-tropical ocean, while increasing our general knowledge of the Ocean microbiome.


Assuntos
Metagenoma , Plâncton , Archaea/genética , Bactérias/genética , Oceanos e Mares , Plâncton/genética
8.
Sci Rep ; 14(1): 4648, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409194

RESUMO

Mangrove forests are recognized as one of the most effective ecosystems for storing carbon. In drylands, mangroves operate at the extremes of environmental gradients and, in many instances, offer one of the few opportunities for vegetation-based sequestering of carbon. Developing accurate and reproducible methods to map carbon assimilation in mangroves not only serves to inform efforts related to natural capital accounting, but can help to motivate their protection and preservation. Remote sensing offers a means to retrieve numerous vegetation traits, many of which can be related to plant biophysical or biochemical responses. The leaf area index (LAI) is routinely employed as a biophysical indicator of health and condition. Here, we apply a linear regression model to UAV-derived multispectral data to retrieve LAI across three mangrove sites located along the coastline of the Red Sea, with estimates producing an R2 of 0.72 when compared against ground-sampled LiCOR LAI-2200C LAI data. To explore the potential of monitoring carbon assimilation within these mangrove stands, the UAV-derived LAI estimates were combined with field-measured net photosynthesis rates from a LiCOR 6400/XT, providing a first estimate of carbon assimilation in dryland mangrove systems of approximately 3000 ton C km-2 yr-1. Overall, these results advance our understanding of carbon assimilation in dryland mangroves and provide a mechanism to quantify the carbon mitigation potential of mangrove reforestation efforts.

9.
Nat Commun ; 15(1): 126, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38168083

RESUMO

Microbial interactions are vital in maintaining ocean ecosystem function, yet their dynamic nature and complexity remain largely unexplored. Here, we use association networks to investigate possible ecological interactions in the marine microbiome among archaea, bacteria, and picoeukaryotes throughout different depths and geographical regions of the tropical and subtropical global ocean. Our findings reveal that potential microbial interactions change with depth and geographical scale, exhibiting highly heterogeneous distributions. A few potential interactions were global, meaning they occurred across regions at the same depth, while 11-36% were regional within specific depths. The bathypelagic zone had the lowest proportion of global associations, and regional associations increased with depth. Moreover, we observed that most surface water associations do not persist in deeper ocean layers despite microbial vertical dispersal. Our work contributes to a deeper understanding of the tropical and subtropical global ocean interactome, which is essential for addressing the challenges posed by global change.


Assuntos
Bactérias , Microbiota , Bactérias/genética , Archaea/genética , Consórcios Microbianos , Oceanos e Mares , Água do Mar/microbiologia
10.
Sci Total Environ ; 914: 169984, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38218470

RESUMO

The Red Sea has been recognized as a coral reef refugia, but it is vulnerable to warming and pollution. Here we investigated the spatial and temporal trends of 15 element concentrations in 9 coral reef sediment cores (aged from the 1460s to the 1980s AD) to study the influence of global warming and industrialization on the Eastern Red Sea coral reefs. We found Na, Ca, Cr, Fe, Co, Ni, and Sr concentrations were higher in the northern Red Sea (i.e., Yanbu), whereas Mg, P, S, Mn, and Cd concentrations were higher in the southern Red Sea (i.e., Thuwal & Al Lith) reef sediments. In the central (i.e., Thuwal) to southern (i.e., Al Lith) Red Sea, the study revealed diverse temporal trends in element concentrations. However, both reef sedimentation rates (-36.4 % and -80.5 %, respectively) and elemental accumulation rates (-49.4 % for Cd to -12.2 % for Zn in Thuwal, and -86.2 % for Co to -61.4 % for Cu in Al Lith) exhibited a declining pattern over time, possibly attributed to warming-induced thermal bleaching. In the central to northern Red Sea (i.e., Yanbu), the severity of thermal bleaching is low, while the reef sedimentation rates (187 %), element concentrations (6.7 % for S to 764 % for Co; except Na, Mg, Ca, Sr, and Cd), and all elemental accumulation rates (190 % for Mg to 2697 % for Co) exponentially increased from the 1970s, probably due the rapid industrialization in Yanbu. Our study also observed increased trace metal concentrations (e.g., Cu, Zn, and Ni) in the Thuwal and Al Lith coral reefs with severe bleaching histories, consistent with previous reports that trace metals might result in decreased resistance of corals to thermal stress under warming scenarios. Our study points to the urgent need to reduce the local discharge of trace metal pollutants to protect this biodiversity hotspot.


Assuntos
Antozoários , Recifes de Corais , Animais , Aquecimento Global , Oceano Índico , Cádmio , Desenvolvimento Industrial
11.
Proc Biol Sci ; 291(2015): 20231614, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38264782

RESUMO

Our ability to assess biodiversity at relevant spatial and temporal scales for informing management is of increasing importance given this is foundational to identify and mitigate the impacts of global change. Collecting baseline information and tracking ecological changes are particularly important for areas experiencing rapid changes and representing data gaps such as Arctic marine ecosystems. Environmental DNA has the potential to provide such data. We extracted environmental DNA from 90 surface sediment samples to assess eukaryote diversity around Greenland and Svalbard using two separate primer pairs amplifying different sections of the 18S rRNA gene. We detected 27 different phyla and 99 different orders and found that temperature and the change in temperature explained the most variation in the community in a single linear model, while latitude, sea ice cover and change in temperature explained the most variation in the community when assessed by individual non-linear models. We identified potential indicator taxa for Arctic climate change, including a terebellid annelid worm. In conclusion, our study demonstrates that environmental DNA offers a feasible method to assess biodiversity and identifies warming as a key driver of differences in biodiversity across these remote ecosystems.


Assuntos
DNA Ambiental , Ecossistema , Biodiversidade , Clima , Sedimentos Geológicos
12.
Mol Ecol ; 33(4): e17260, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38197286

RESUMO

Biological systems occurring in ecologically heterogeneous and spatially discontinuous habitats provide an ideal opportunity to investigate the relative roles of neutral and selective factors in driving lineage diversification. The grey mangroves (Avicennia marina) of Arabia occur at the northern edge of the species' range and are subject to variable, often extreme, environmental conditions, as well as historic large fluctuations in habitat availability and connectivity resulting from Quaternary glacial cycles. Here, we analyse fully sequenced genomes sampled from 19 locations across the Red Sea, the Arabian Sea and the Persian/Arabian Gulf (PAG) to reconstruct the evolutionary history of the species in the region and to identify adaptive mechanisms of lineage diversification. Population structure and phylogenetic analyses revealed marked genetic structure correlating with geographic distance and highly supported clades among and within the seas surrounding the Arabian Peninsula. Demographic modelling showed times of divergence consistent with recent periods of geographic isolation and low marine connectivity during glaciations, suggesting the presence of (cryptic) glacial refugia in the Red Sea and the PAG. Significant migration was detected within the Red Sea and the PAG, and across the Strait of Hormuz to the Arabian Sea, suggesting gene flow upon secondary contact among populations. Genetic-environment association analyses revealed high levels of adaptive divergence and detected signs of multi-loci local adaptation driven by temperature extremes and hypersalinity. These results support a process of rapid diversification resulting from the combined effects of historical factors and ecological selection and reveal mangrove peripheral environments as relevant drivers of lineage diversity.


Assuntos
Avicennia , Filogenia , Avicennia/genética , Arábia , Ecossistema , Oceano Índico
13.
Sci Rep ; 14(1): 752, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191897

RESUMO

Climate change and human activity threaten sea turtle nesting beaches through increased flooding and erosion. Understanding the environmental characteristics that enable nesting can aid to preserve and expand these habitats. While numerous local studies exist, a comprehensive global analysis of environmental influences on the distribution of sea turtle nesting habitats remains largely unexplored. Here, we relate the distribution of global sea turtle nesting to 22 coastal indicators, spanning hydrodynamic, atmospheric, geophysical, habitat, and human processes. Using state-of-the-art global datasets and a novel 50-km-resolution hexagonal coastline grid (Coastgons), we employ machine learning to identify spatially homogeneous patterns in the indicators and correlate these to the occurrence of nesting grounds. Our findings suggest sea surface temperature, tidal range, extreme surges, and proximity to coral and seagrass habitats significantly influence global nesting distribution. Low tidal ranges and low extreme surges appear to be particularly favorable for individual species, likely due to reduced nest flooding. Other indicators, previously reported as influential (e.g., precipitation and wind speed), were not as important in our global-scale analysis. Finally, we identify new, potentially suitable nesting regions for each species. On average, [Formula: see text] of global coastal regions between [Formula: see text] and [Formula: see text] latitude could be suitable for nesting, while only [Formula: see text] is currently used by turtles, showing that the realized niche is significantly smaller than the fundamental niche, and that there is potential for sea turtles to expand their nesting habitat. Our results help identify suitable nesting conditions, quantify potential hazards to global nesting habitats, and lay a foundation for nature-based solutions to preserve and potentially expand these habitats.


Assuntos
Antozoários , Tartarugas , Humanos , Animais , Mudança Climática , Sistemas Computacionais , Inundações
14.
Mol Psychiatry ; 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233468

RESUMO

Fear-related pathologies are among the most prevalent psychiatric conditions, having inappropriate learned fear and resistance to extinction as cardinal features. Exposure therapy represents a promising therapeutic approach, the efficiency of which depends on inter-individual variation in fear extinction learning, which neurobiological basis is unknown. We characterized a model of extinction learning, whereby fear-conditioned mice were categorized as extinction (EXT)-success or EXT-failure, according to their inherent ability to extinguish fear. In the lateral amygdala, GluN2A-containing NMDAR are required for LTP and stabilization of fear memories, while GluN2B-containing NMDAR are required for LTD and fear extinction. EXT-success mice showed attenuated LTP, strong LTD and higher levels of synaptic GluN2B, while EXT-failure mice showed strong LTP, no LTD and higher levels of synaptic GluN2A. Neurotrophin 3 (NT3) infusion in the lateral amygdala was sufficient to rescue extinction deficits in EXT-failure mice. Mechanistically, activation of tropomyosin receptor kinase C (TrkC) with NT3 in EXT-failure slices attenuated lateral amygdala LTP, in a GluN2B-dependent manner. Conversely, blocking endogenous NT3-TrkC signaling with TrkC-Fc chimera in EXT-success slices strengthened lateral amygdala LTP. Our data support a key role for the NT3-TrkC system in inter-individual differences in fear extinction in rodents, through modulation of amygdalar NMDAR composition and synaptic plasticity.

15.
Respir Care ; 69(2): 202-209, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-37963609

RESUMO

BACKGROUND: Epidemiological data on patients with COVID-19 referred to specialized weaning centers (SWCs) are sparse, particularly in low- and middle-income countries. Our aim was to describe clinical features, epidemiology, and outcomes of subjects admitted to SWCs in Argentina. METHODS: We conducted a prospective, multi-center, observational study between July 2020-December 2021 in 12 SWCs. We collected demographic characteristics, laboratory results, pulmonary function, and dependence on mechanical ventilation at admission, decannulation, weaning from mechanical ventilation, and status at discharge. A multiple logistic model was built to predict home discharge. RESULTS: We enrolled 568 tracheostomized adult subjects after the acute COVID-19 phase who were transferred to SWCs. Age was 62 [52-71], males 70%, Charlson comorbidity index was 2 [0-3], and length of stay in ICU was 42 [32-56] d. Of the 315 ventilator-dependent subjects, 72.4% were weaned, 427 (75.2%) were decannulated, and 366 subjects (64.5%) were discharged home. The mortality rate was 6.0%. In multivariate analysis, age (odds ratio 0.30 [95% CI 0.16-0.56], P < .001), Charlson comorbidity index (odds ratio 0.43 [95% CI 0.22-0.84], P < .01), mechanical ventilation duration in ICU (odds ratio 0.80 [95% CI 0.72-0.89], P < .001), renal failure (odds ratio 0.40 [95% CI 0.22-0.73], P = .003), and expiratory muscle weakness (odds ratio 0.35 [95% CI 0.19-0.62], P < .001) were independently associated with home discharge. CONCLUSIONS: Most subjects with COVID-19 transferred to SWCs were weaned, achieved decannulation, and were discharged to home. Age, high-comorbidity burden, prolonged mechanical ventilation in ICU, renal failure at admission, and expiratory muscle weakness were inversely associated with home discharge.


Assuntos
COVID-19 , Insuficiência Renal , Humanos , Masculino , COVID-19/epidemiologia , Debilidade Muscular , Estudos Prospectivos , Respiração Artificial , Desmame do Respirador , Feminino , Pessoa de Meia-Idade , Idoso
16.
Sci Adv ; 9(45): eadg9763, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37939185

RESUMO

Tiny ocean plankton (picoplankton) are fundamental for the functioning of the biosphere, but the ecological mechanisms shaping their biogeography were partially understood. Comprehending whether these microorganisms are structured by niche versus neutral processes is relevant in the context of global change. We investigate the ecological processes (selection, dispersal, and drift) structuring global-ocean picoplanktonic communities inhabiting the epipelagic (0 to 200 meters), mesopelagic (200 to 1000 meters), and bathypelagic (1000 to 4000 meters) zones. We found that selection decreased, while dispersal limitation increased with depth, possibly due to differences in habitat heterogeneity and dispersal barriers such as water masses and bottom topography. Picoplankton ß-diversity positively correlated with environmental heterogeneity and water mass variability, but this relationship tended to be weaker for eukaryotes than for prokaryotes. Community patterns were more pronounced in the Mediterranean Sea, probably because of its cross-basin environmental heterogeneity and deep-water isolation. We conclude that different combinations of ecological mechanisms shape the biogeography of the ocean microbiome across depths.


Assuntos
Microbiota , Plâncton , Eucariotos , Água , Oceanos e Mares
17.
Cureus ; 15(9): e45494, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37859921

RESUMO

Although muscle injuries represent the most frequent injury in professional football, isolated complete distal ruptures of the rectus femoris (RF) muscle are rare, and there is no consensus on their treatment and return to play (RTP). In this article, we report a clinical case of successful non-surgical management of an RF grade 4c muscle injury in a professional football player, in which the athlete was able to RTP 21 weeks after the injury, had no re-injury >1 year after RTP, and is playing at an elite level in the Portuguese Football First League.

18.
ISME Commun ; 3(1): 92, 2023 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-37660234

RESUMO

Traditional culture techniques usually retrieve a small fraction of the marine microbial diversity, which mainly belong to the so-called rare biosphere. However, this paradigm has not been fully tested at a broad scale, especially in the deep ocean. Here, we examined the fraction of heterotrophic bacterial communities in photic and deep ocean layers that could be recovered by culture-dependent techniques at a large scale. We compared 16S rRNA gene sequences from a collection of 2003 cultured heterotrophic marine bacteria with global 16S rRNA metabarcoding datasets (16S TAGs) covering surface, mesopelagic and bathypelagic ocean samples that included 16 of the 23 samples used for isolation. These global datasets represent 60 322 unique 16S amplicon sequence variants (ASVs). Our results reveal a significantly higher proportion of isolates identical to ASVs in deeper ocean layers reaching up to 28% of the 16S TAGs of the bathypelagic microbial communities, which included the isolation of 3 of the top 10 most abundant 16S ASVs in the global bathypelagic ocean, related to the genera Sulfitobacter, Halomonas and Erythrobacter. These isolates contributed differently to the prokaryotic communities across different plankton size fractions, recruiting between 38% in the free-living fraction (0.2-0.8 µm) and up to 45% in the largest particles (20-200 µm) in the bathypelagic ocean. Our findings support the hypothesis that sinking particles in the bathypelagic act as resource-rich habitats, suitable for the growth of heterotrophic bacteria with a copiotroph lifestyle that can be cultured, and that these cultivable bacteria can also thrive as free-living bacteria.

19.
Sci Rep ; 13(1): 15412, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37723196

RESUMO

Oceans are crucial to human survival, providing natural resources and most of the global oxygen supply, and are responsible for a large portion of worldwide economic development. Although it is widely considered a silent world, the sea is filled with natural sounds generated by marine life and geological processes. Man-made underwater sounds, such as active sonars, maritime traffic, and offshore oil and mineral exploration, have significantly affected underwater soundscapes and species. In this work, we report on a joint optical fiber-based communication and sensing technology aiming to reduce noise pollution in the sea while providing connectivity simultaneously with a variety of underwater applications. The designed multifunctional fiber-based system enables two-way data transfer, monitoring marine life and ship movement near the deployed fiber at the sea bottom and sensing temperature. The deployed fiber is equally harnessed to transfer energy that the internet of underwater things (IoUTs) devices can harvest. The reported approach significantly reduces the costs and effects of monitoring marine ecosystems while ensuring data transfer and ocean monitoring applications and providing continuous power for submerged IoUT devices.

20.
Sci Total Environ ; 904: 166185, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37591400

RESUMO

Coastal blue carbon ecosystems offer promising benefits for both climate change mitigation and adaptation. While there have been widespread efforts to transplant mangroves from the tropics to the subtropics and to introduce exotic saltmarsh plants like Spartina alterniflora in China, few studies have thoroughly quantified the chronological records of carbon sequestration with different organic carbon (OC) sources. To understand how variations in OC sources can affect the carbon sequestration potential of coastal wetland environment over time, we conducted a study on typical islands with two scenarios: S. alterniflora invasion and mangrove transplantation. Our study determined chronological records of carbon sequestration and storage from five sediment profiles and traced changes in the OC sources using carbon stable isotope (δ13C) and C:N ratios in response to these scenarios. The S. alterniflora invasion resulted in an 84 ± 19 % increase in the OC burial rate compared to unvegetated mudflats, while mangrove transplantation resulted in a 167 ± 74 % increase in the OC burial rate compared to unvegetated mudflats. S. alterniflora and mangroves showed greater carbon sequestration potential in areas with high supplies of suspended particulate matter, while mangroves needed to grow to a certain scale to display obvious carbon sequestration benefits. In the mangrove saltmarsh ecotone, mature mangrove habitats exhibited resistance to the S. alterniflora invasion, while mangrove transplantation in the environment invaded by S. alterniflora had a significant effect on OC contribution. Besides, plant-derived OC can be exported to the surrounding environment due to the rapid turnover of sediments. The blue carbon chronosequence-based estimation of OC sources and burial rates provides a useful reference for establishing carbon accounting policies.


Assuntos
Ecossistema , Áreas Alagadas , Sequestro de Carbono , Espécies Introduzidas , Plantas , Poaceae/fisiologia , Carbono/análise , Isótopos de Carbono , China
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