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1.
Nature ; 625(7993): 85-91, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38172362

RESUMO

The world's population increasingly relies on the ocean for food, energy production and global trade1-3, yet human activities at sea are not well quantified4,5. We combine satellite imagery, vessel GPS data and deep-learning models to map industrial vessel activities and offshore energy infrastructure across the world's coastal waters from 2017 to 2021. We find that 72-76% of the world's industrial fishing vessels are not publicly tracked, with much of that fishing taking place around South Asia, Southeast Asia and Africa. We also find that 21-30% of transport and energy vessel activity is missing from public tracking systems. Globally, fishing decreased by 12 ± 1% at the onset of the COVID-19 pandemic in 2020 and had not recovered to pre-pandemic levels by 2021. By contrast, transport and energy vessel activities were relatively unaffected during the same period. Offshore wind is growing rapidly, with most wind turbines confined to small areas of the ocean but surpassing the number of oil structures in 2021. Our map of ocean industrialization reveals changes in some of the most extensive and economically important human activities at sea.


Assuntos
Atividades Humanas , Indústrias , Oceanos e Mares , Imagens de Satélites , Humanos , COVID-19/epidemiologia , Aprendizado Profundo , Fontes Geradoras de Energia/estatística & dados numéricos , Abastecimento de Alimentos/estatística & dados numéricos , Sistemas de Informação Geográfica , Mapeamento Geográfico , Atividades Humanas/economia , Atividades Humanas/estatística & dados numéricos , Caça/estatística & dados numéricos , Indústrias/economia , Indústrias/estatística & dados numéricos , Navios/estatística & dados numéricos , Vento
2.
Mol Cell ; 80(3): 381-383, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33157013

RESUMO

Recent work by Licznerski et al. suggests that mutant FMRP linked to Fragile-X syndrome elevates the inner mitochondrial membrane proton leak, leading to increased metabolism and changes in protein synthesis that trigger impaired synaptic maturation and autistic behaviors.


Assuntos
Síndrome do Cromossomo X Frágil , Trifosfato de Adenosina , Proteína do X Frágil da Deficiência Intelectual/genética , Síndrome do Cromossomo X Frágil/genética , Humanos , Mitocôndrias/genética , Navios
3.
Proc Natl Acad Sci U S A ; 121(30): e2400425121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39012818

RESUMO

In the centuries following Christopher Columbus's 1492 voyage to the Americas, transoceanic travel opened unprecedented pathways in global pathogen circulation. Yet no biological transfer is a single, discrete event. We use mathematical modeling to quantify historical risk of shipborne pathogen introduction, exploring the respective contributions of journey time, ship size, population susceptibility, transmission intensity, density dependence, and pathogen biology. We contextualize our results using port arrivals data from San Francisco, 1850 to 1852, and from a selection of historically significant voyages, 1492 to 1918. We offer numerical estimates of introduction risk across historically realistic ranges of journey time and ship population size, and show that both steam travel and shipping regimes that involved frequent, large-scale movement of people substantially increased risk of transoceanic pathogen circulation.


Assuntos
Navios , Viagem , Humanos , Vapor , Modelos Teóricos , São Francisco/epidemiologia , História do Século XX , História do Século XIX
4.
Proc Natl Acad Sci U S A ; 121(2): e2308125121, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38175864

RESUMO

We estimate the basic reproductive number and case counts for 15 distinct Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreaks, distributed across 11 populations (10 countries and one cruise ship), based solely on phylodynamic analyses of genomic data. Our results indicate that, prior to significant public health interventions, the reproductive numbers for 10 (out of 15) of these outbreaks are similar, with median posterior estimates ranging between 1.4 and 2.8. These estimates provide a view which is complementary to that provided by those based on traditional line listing data. The genomic-based view is arguably less susceptible to biases resulting from differences in testing protocols, testing intensity, and import of cases into the community of interest. In the analyses reported here, the genomic data primarily provide information regarding which samples belong to a particular outbreak. We observe that once these outbreaks are identified, the sampling dates carry the majority of the information regarding the reproductive number. Finally, we provide genome-based estimates of the cumulative number of infections for each outbreak. For 7 out of 11 of the populations studied, the number of confirmed cases is much bigger than the cumulative number of infections estimated from the sequence data, a possible explanation being the presence of unsequenced outbreaks in these populations.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Surtos de Doenças , Genômica , Navios
5.
Nature ; 572(7770): 461-466, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31340216

RESUMO

Effective ocean management and the conservation of highly migratory species depend on resolving the overlap between animal movements and distributions, and fishing effort. However, this information is lacking at a global scale. Here we show, using a big-data approach that combines satellite-tracked movements of pelagic sharks and global fishing fleets, that 24% of the mean monthly space used by sharks falls under the footprint of pelagic longline fisheries. Space-use hotspots of commercially valuable sharks and of internationally protected species had the highest overlap with longlines (up to 76% and 64%, respectively), and were also associated with significant increases in fishing effort. We conclude that pelagic sharks have limited spatial refuge from current levels of fishing effort in marine areas beyond national jurisdictions (the high seas). Our results demonstrate an urgent need for conservation and management measures at high-seas hotspots of shark space use, and highlight the potential of simultaneous satellite surveillance of megafauna and fishers as a tool for near-real-time, dynamic management.


Assuntos
Migração Animal , Pesqueiros/estatística & dados numéricos , Mapeamento Geográfico , Oceanos e Mares , Tubarões/fisiologia , Análise Espaço-Temporal , Animais , Densidade Demográfica , Medição de Risco , Tubarões/classificação , Navios , Fatores de Tempo
6.
Proc Natl Acad Sci U S A ; 119(20): e2117440119, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35533277

RESUMO

Marine traffic is increasing globally yet collisions with endangered megafauna such as whales, sea turtles, and planktivorous sharks go largely undetected or unreported. Collisions leading to mortality can have population-level consequences for endangered species. Hence, identifying simultaneous space use of megafauna and shipping throughout ranges may reveal as-yet-unknown spatial targets requiring conservation. However, global studies tracking megafauna and shipping occurrences are lacking. Here we combine satellite-tracked movements of the whale shark, Rhincodon typus, and vessel activity to show that 92% of sharks' horizontal space use and nearly 50% of vertical space use overlap with persistent large vessel (>300 gross tons) traffic. Collision-risk estimates correlated with reported whale shark mortality from ship strikes, indicating higher mortality in areas with greatest overlap. Hotspots of potential collision risk were evident in all major oceans, predominantly from overlap with cargo and tanker vessels, and were concentrated in gulf regions, where dense traffic co-occurred with seasonal shark movements. Nearly a third of whale shark hotspots overlapped with the highest collision-risk areas, with the last known locations of tracked sharks coinciding with busier shipping routes more often than expected. Depth-recording tags provided evidence for sinking, likely dead, whale sharks, suggesting substantial "cryptic" lethal ship strikes are possible, which could explain why whale shark population declines continue despite international protection and low fishing-induced mortality. Mitigation measures to reduce ship-strike risk should be considered to conserve this species and other ocean giants that are likely experiencing similar impacts from growing global vessel traffic.


Assuntos
Tubarões , Animais , Espécies em Perigo de Extinção , Plâncton , Navios
7.
Proc Natl Acad Sci U S A ; 119(3)2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35012982

RESUMO

Antarctica, an isolated and long considered pristine wilderness, is becoming increasingly exposed to the negative effects of ship-borne human activity, and especially the introduction of invasive species. Here, we provide a comprehensive quantitative analysis of ship movements into Antarctic waters and a spatially explicit assessment of introduction risk for nonnative marine species in all Antarctic waters. We show that vessels traverse Antarctica's isolating natural barriers, connecting it directly via an extensive network of ship activity to all global regions, especially South Atlantic and European ports. Ship visits are more than seven times higher to the Antarctic Peninsula (especially east of Anvers Island) and the South Shetland Islands than elsewhere around Antarctica, together accounting for 88% of visits to Southern Ocean ecoregions. Contrary to expectations, we show that while the five recognized "Antarctic Gateway cities" are important last ports of call, especially for research and tourism vessels, an additional 53 ports had vessels directly departing to Antarctica from 2014 to 2018. We identify ports outside Antarctica where biosecurity interventions could be most effectively implemented and the most vulnerable Antarctic locations where monitoring programs for high-risk invaders should be established.


Assuntos
Ecossistema , Navios , Meios de Transporte , Regiões Antárticas , Geografia , Espécies Introduzidas
8.
Proc Natl Acad Sci U S A ; 119(29): e2207612119, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858363

RESUMO

"Milky seas" are massive swaths of uniformly and steadily glowing ocean seen at night. The phenomenon is thought to be caused by luminous bacteria, but details of milky sea composition, structure, cause, and implications in nature remain largely uncertain. Between late July and early September 2019, specialized low-light satellite sensors detected a possible bioluminescent milky sea south of Java, Indonesia, spanning >100,000 km2. Upon learning of these findings, crew members of the yacht Ganesha reached out to confirm and share details of their personal encounter with this same event. Here, we document Ganesha's experience as recalled by the crew, compare their course to satellite data, and assess their photography of this milky sea.


Assuntos
Bactérias , Imagens de Satélites , Água do Mar , Navios , Indonésia , Luminescência , Oceanos e Mares , Água do Mar/microbiologia
9.
Proc Natl Acad Sci U S A ; 119(41): e2206885119, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36191195

RESUMO

Global shipping accounts for 13% of global emissions of SO2, which, once oxidized to sulfate aerosol, acts to cool the planet both directly by scattering sunlight and indirectly by increasing the albedo of clouds. This cooling due to sulfate aerosol offsets some of the warming effect of greenhouse gasses and is the largest uncertainty in determining the change in the Earth's radiative balance by human activity. Ship tracks-the visible manifestation of the indirect of effect of ship emissions on clouds as quasi-linear features-have long provided an opportunity to quantify these effects. However, they have been arduous to catalog and typically studied only in particular regions for short periods of time. Using a machine-learning algorithm to automate their detection we catalog more than 1 million ship tracks to provide a global climatology. We use this to investigate the effect of stringent fuel regulations introduced by the International Maritime Organization in 2020 on their global prevalence since then, while accounting for the disruption in global commerce caused by COVID-19. We find a marked, but clearly nonlinear, decline in ship tracks globally: An 80% reduction in SO[Formula: see text] emissions causes only a 25% reduction in the number of tracks detected.


Assuntos
COVID-19 , Gases de Efeito Estufa , COVID-19/epidemiologia , Humanos , Aerossóis e Gotículas Respiratórios , Navios , Sulfatos/análise
10.
Emerg Infect Dis ; 30(5): 1030-1033, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38666667

RESUMO

Cruise ships carrying COVID-19-vaccinated populations applied near-identical nonpharmaceutical measures during July-November 2021; passenger masking was not applied on 2 ships. Infection risk for masked passengers was 14.58 times lower than for unmasked passengers and 19.61 times lower than in the community. Unmasked passengers' risk was slightly lower than community risk.


Assuntos
COVID-19 , SARS-CoV-2 , Navios , COVID-19/prevenção & controle , COVID-19/epidemiologia , Humanos , Viagem , Vacinas contra COVID-19/administração & dosagem , Máscaras
11.
J Exp Biol ; 227(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38099450

RESUMO

Anthropogenic noise is becoming a major underwater pollutant because of rapidly increasing boat traffic worldwide. But its impact on aquatic organisms remains largely unknown. Previous studies have focused mainly on high-frequency and impulsive noises (i.e. sonar); however, boat noise is more pervasive, continuous, and its highest intensity and component frequencies overlap the auditory bandwidth of most fishes. We assessed the impacts of boat noise on saccular sensory hair cell density and hearing thresholds of a soniferous species, Atlantic croaker (Micropogonias undulatus). In two laboratory experiments, individuals were subjected to simulated boat noise: a single 15-min exposure and 3 days of intermittent noise (simulating passing vessels). Immediately after both experiments, fish were either (1) tested for hearing sensitivity with auditory evoked potential (AEP) tests or (2) euthanized for fluorescent phalloidin and TUNEL labeling for hair cell density counts. Relative to controls, no differences were observed in auditory thresholds nor hair cell density between individuals subjected to a single 15-min noise exposure. However, fish from the 3-day experiment showed decreased sensory hair cell density, increased apoptotic cells, and higher hearing thresholds than control fish at 300, 800 and 1000 Hz. Our results demonstrate that impacts from boat noise depend upon the duration and frequency of exposure. For a species reliant on vocalization for communication, these impacts may hinder spawning success, increase predation risks and significantly alter the ecosystem.


Assuntos
Perciformes , Navios , Animais , Ecossistema , Audição , Perciformes/fisiologia , Células Ciliadas Auditivas/fisiologia , Peixes/fisiologia , Limiar Auditivo/fisiologia
12.
PLoS Comput Biol ; 19(11): e1011656, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38011267

RESUMO

The influenza pandemic of 1918-19 was the most devastating pandemic of the 20th century. It killed an estimated 50-100 million people worldwide. In late 1918, when the severity of the disease was apparent, the Australian Quarantine Service was established. Vessels returning from overseas and inter-state were intercepted, and people were examined for signs of illness and quarantined. Some of these vessels carried the infection throughout their voyage and cases were prevalent by the time the ship arrived at a Quarantine Station. We study four outbreaks that took place on board the Medic, Boonah, Devon, and Manuka in late 1918. These ships had returned from overseas and some of them were carrying troops that served in the First World War. By analysing these outbreaks under a stochastic Bayesian hierarchical modeling framework, we estimate the transmission rates among crew and passengers aboard these ships. Furthermore, we ask whether the removal of infectious, convalescent, and healthy individuals after arriving at a Quarantine Station in Australia was an effective public health response.


Assuntos
Influenza Humana , Navios , Humanos , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Pandemias/prevenção & controle , Teorema de Bayes , Hospitais de Isolamento , Austrália/epidemiologia , Surtos de Doenças/prevenção & controle , Viagem
13.
Conserv Biol ; 38(3): e14224, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38111961

RESUMO

Seabirds interact with fishing vessels to consume fishing discards and baits, sometimes resulting in incidental capture (bycatch) and the death of the bird, which has clear conservation implications. To understand seabird-fishery interactions at large spatiotemporal scales, researchers are increasing their use of simultaneous seabird and fishing vessel tracking. However, vessel tracking data can contain gaps due to technical problems, illicit manipulation, or lack of adoption of tracking monitoring systems. These gaps might lead to underestimating the fishing effort and bycatch rates and jeopardize the effectiveness of marine conservation. We deployed bird-borne radar detector tags capable of recording radar signals from vessels. We placed tags on 88 shearwaters (Calonectris diomedea, Calonectris borealis, and Calonectris edwardsii) that forage in the northwestern Mediterranean Sea and the Canary Current Large Marine Ecosystem. We modeled vessel radar detections registered by the tags in relation to gridded automatic identification system (AIS) vessel tracking data to examine the spatiotemporal dynamics of seabird-vessel interactions and identify unreported fishing activity areas. Our models showed a moderate fit (area under the curve >0.7) to vessel tracking data, indicating a strong association of shearwaters to fishing vessels in major fishing grounds. Although in high-marine-traffic regions, radar detections were also driven by nonfishing vessels. The tags registered the presence of potential unregulated and unreported fishing vessels in West African waters, where merchant shipping is unusual but fishing activity is intense. Overall, bird-borne radar detectors showed areas and periods when the association of seabirds with legal and illegal fishing vessels was high. Bird-borne radar detectors could improve the focus of conservation efforts.


Uso de radares en aves para analizar las interacciones de las pardelas con las pesquerías legales e ilegales Resumen Las aves marinas interactúan con los barcos pesqueros para consumir los cebos y lo que descartan, lo que a veces resulta en la captura accesoria y la muerte del ave, por lo que esto tiene implicaciones claras para la conservación. Los investigadores cada vez usan más el rastreo simultáneo de las aves marinas y los barcos pesqueros para comprender las interacciones aves marinas ­ pesquerías a gran escala espaciotemporal. Sin embargo, los datos del rastreo de barcos pueden incluir vacíos por problemas técnicos, manipulación ilícita o porque no adoptan sistemas para monitorear el rastreo. Estos vacíos pueden llevar a subestimar el esfuerzo de pesca y las tasas de captura accesoria y a comprometer la efectividad de la conservación marina. Desplegamos marcas detectoras de radar encima de aves capaces de registrar las señales de radar de los barcos. Colocamos estas marcas en 88 pardelas (Calonectris diomedea, C. borealis, y C. edwardsii) que forrajean en el noroeste del Mar Mediterráneo y el Gran Ecosistema Marino de Canarias. Modelamos las detecciones del radar de los barcos registradas por las marcas en relación con los datos reticulados de rastreo de barcos del sistema de identificación automático (AIS) para analizar las dinámicas espaciotemporales de las interacciones aves marinas­barcos e identificar áreas con actividad pesquera no reportada. Nuestros modelos mostraron un ajuste moderado (área bajo la curva > 0.7) a los datos de rastreo de barcos, lo que indica una fuerte asociación entre las pardelas y los barcos en los principales sitios de pesca, aunque en las regiones con alto tránsito de barcos las detecciones por radar también fueron causadas por barcos no pesqueros. Las marcas registraron la presencia del potencial de barcos pesqueros sin regular y sin reportar en aguas del oeste de África, en donde los buques mercantes son poco comunes pero la actividad pesquera es intensa. En general, los detectores por radar en las aves mostraron áreas y periodos en donde la asociación entre las aves marinas y los barcos pesqueros legales e ilegales es alta. Estos detectores por radar podrían mejorar el enfoque de los esfuerzos de conservación.


Assuntos
Aves , Conservação dos Recursos Naturais , Pesqueiros , Radar , Animais , Aves/fisiologia , Conservação dos Recursos Naturais/métodos , Mar Mediterrâneo , Navios , Espanha
14.
Environ Sci Technol ; 58(21): 9328-9338, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38739556

RESUMO

In the present study, we applied forensic geochemistry to investigate the origin and fate of spilled oils like tarballs stranded at the beaches of Bahia, in northeastern Brazil, in September 2023, based on their fingerprints. Saturated and aromatic compounds were assessed by gas chromatography, and the oceanic surface circulation patterns were deciphered to determine the geographic origin of the spill. Contamination by petroleum represents an enormous threat to the unique, species-rich ecosystems of the study area. The geochemical fingerprint of the oil spilled in 2023 did not correlate with those of previous events, including the one in 2019, the one in early 2022 in Ceará, and an extensive spill across the Brazilian Northeast in late 2022. However, the fingerprint did correlate with crude oils produced by Middle Eastern countries, most likely Kuwait. The oil of the 2023 spill had a carbonate marine origin from early mature source rocks. These findings, together with the moderate weathering of the 2023 tarballs and the ocean circulation patterns at the time of the event, indicate that the oil was discharged close to the shore of Brazil, to the east or southeast of Salvador, by a tanker on an international route in the South Atlantic.


Assuntos
Poluição por Petróleo , Navios , Brasil , Monitoramento Ambiental , Petróleo , Poluentes Químicos da Água/análise
15.
Nature ; 617(7960): 226, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37117700
20.
Nature ; 553(7686): 68-72, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29258293

RESUMO

Designing materials to function in harsh environments, such as conductive aqueous media, is a problem of broad interest to a range of technologies, including energy, ocean monitoring and biological applications. The main challenge is to retain the stability and morphology of the material as it interacts dynamically with the surrounding environment. Materials that respond to mild stimuli through collective phase transitions and amplify signals could open up new avenues for sensing. Here we present the discovery of an electric-field-driven, water-mediated reversible phase change in a perovskite-structured nickelate, SmNiO3. This prototypical strongly correlated quantum material is stable in salt water, does not corrode, and allows exchange of protons with the surrounding water at ambient temperature, with the concurrent modification in electrical resistance and optical properties being capable of multi-modal readout. Besides operating both as thermistors and pH sensors, devices made of this material can detect sub-volt electric potentials in salt water. We postulate that such devices could be used in oceanic environments for monitoring electrical signals from various maritime vessels and sea creatures.


Assuntos
Compostos de Cálcio/química , Eletricidade , Níquel/química , Compostos Organometálicos/química , Óxidos/química , Cloreto de Sódio/química , Titânio/química , Água/química , Organismos Aquáticos , Concentração de Íons de Hidrogênio , Transição de Fase , Prótons , Navios , Síncrotrons , Temperatura
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