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1.
Br J Surg ; 110(6): 645-654, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-36752583

RESUMO

BACKGROUND: Although numerous studies have established cognitive biases as contributors to surgical adverse events, their prevalence and impact in surgery are unknown. This review aimed to describe types of cognitive bias in surgery, their impact on surgical performance and patient outcomes, their source, and the mitigation strategies used to reduce their effect. METHODS: A literature search was conducted on 9 April and 6 December 2021 using MEDLINE, Embase, PsycINFO, Scopus, Web of Science, Cochrane Central Register of Controlled Trials, and the Cochrane Database of Systematic Reviews. Included studies investigated how cognitive biases affect surgery and the mitigation strategies used to combat their impact. The National Institutes of Health tools were used to assess study quality. Inductive thematic analysis was used to identify themes of cognitive bias impact on surgical performance. RESULTS: Thirty-nine studies were included, comprising 6514 surgeons and over 200 000 patients. Thirty-one types of cognitive bias were identified, with overconfidence, anchoring, and confirmation bias the most common. Cognitive biases differentially influenced six themes of surgical performance. For example, overconfidence bias associated with inaccurate perceptions of ability, whereas anchoring bias associated with inaccurate risk-benefit estimations and not considering alternative options. Anchoring and confirmation biases associated with actual patient harm, such as never events. No studies investigated cognitive bias source or mitigation strategies. CONCLUSION: Cognitive biases have a negative impact on surgical performance and patient outcomes across all points of surgical care. This review highlights the scarcity of research investigating the sources that give rise to cognitive biases in surgery and the mitigation strategies that target these factors.


Assuntos
Cognição , Estados Unidos , Humanos , Viés
2.
Surg Endosc ; 37(4): 2817-2825, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36478137

RESUMO

BACKGROUND: Intraoperative adverse events lead to patient injury and death, and are increasing. Early warning systems (EWSs) have been used to detect patient deterioration and save lives. However, few studies have used EWSs to monitor surgical performance and caution about imminent technical errors. Previous (non-surgical) research has investigated neural activity to predict future motor errors using electroencephalography (EEG). The present proof-of-concept cohort study investigates whether EEG could predict technical errors in surgery. METHODS: In a large academic hospital, three surgical fellows performed 12 elective laparoscopic general surgeries. Audiovisual data of the operating room and the surgeon's neural activity were recorded. Technical errors and epochs of good surgical performance were coded into events. Neural activity was observed 40 s prior and 10 s after errors and good events to determine how far in advance errors were detected. A hierarchical regression model was used to account for possible clustering within surgeons. This prospective, proof-of-concept, cohort study was conducted from July to November 2021, with a pilot period from February to March 2020 used to optimize the technique of data capture and included participants who were blinded from study hypotheses. RESULTS: Forty-five technical errors, mainly due to too little force or distance (n = 39), and 27 good surgical events were coded during grasping and dissection. Neural activity representing error monitoring (p = .008) and motor uncertainty (p = .034) was detected 17 s prior to errors, but not prior to good surgical performance. CONCLUSIONS: These results show that distinct neural signatures are predictive of technical error in laparoscopic surgery. If replicated with low false-alarm rates, an EEG-based EWS of technical errors could be used to improve individualized surgical training by flagging imminent unsafe actions-before errors occur and cause patient harm.


Assuntos
Competência Clínica , Laparoscopia , Humanos , Estudos de Coortes , Estudos Prospectivos , Laparoscopia/efeitos adversos , Eletroencefalografia
3.
Environ Sci Technol ; 54(7): 4068-4078, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32164416

RESUMO

When fine particulates such as those with a diameter of approximately 1 µm (particulate matter, PM1) are released from fossil fuel combustion into the air, they warm the atmosphere and contribute to millions of premature deaths in humans each year. Considerable quantities of PM1 eventually enter the oceans as suspended particulates, yet subsequent removal mechanisms are poorly understood. In fact, the presence of PM1 in marine biota has never been reported. Since sea anemones are opportunistic suspension feeders, they are anticipated to incorporate and accumulate PM1 in their bodies. By histological examination, PM1 was detected in 21 of the 22 sea anemones collected from Taiwan and Southeast China, with a depth of intertidal zone to 1000 m. PM1, if present, was always detected in endodermal layers and had the same dominant color (i.e., black, brown, or green) in different species from the same site. The bioaccumulation factor of PM1 in sea anemones was approximately 5-7 orders of magnitude. Based on radioisotope 14C results, the contribution of fossil fuel source PM1 was 8-24%. Regardless of PM1's color, S and Fe were commonly detected by scanning electron microscopy and energy-dispersive spectrometry (SEM-EDS), suggesting anthropogenic sources. Furthermore, a maternal transfer of materials was suggested based on the existence of PM1 in sea anemone eggs and in brooding and released juveniles. The significance of PM1 accumulation by biota in aquatic ecosystems and the potential risk to living organisms via food webs warrant further investigation.


Assuntos
Poluentes Atmosféricos , Combustíveis Fósseis , Adolescente , Biota , China , Ecossistema , Monitoramento Ambiental , Humanos , Oceanos e Mares , Tamanho da Partícula , Material Particulado , Taiwan
4.
Environ Microbiol ; 19(9): 3606-3618, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28714207

RESUMO

Chemically mediated interactions have been hypothesized to be essential for ecosystem functioning as co-occurring organisms can influence the performance of each other by metabolic means. Here, we present a co-culture device that allows co-culturing of microorganisms that are physically separated but can exchange chemical signals and metabolites. This setup was adopted to perform investigations on the secondary metabolisms of both a fungal-bacterial community and an actinomycetic-actinomycetic community. This study employed a metabolomics approach integrating LC-MS profiling, multivariate data analysis and molecular networking techniques. LC-MS measurements revealed a pronounced influence of such chemical communication on the metabolic profiles of synthetic co-culture communities with a group of molecules being induced or upregulated in co-cultures. A novel antibiotic exhibiting antibiotic properties against Klebsiella pneumoniae was unveiled in the fungal-bacterial community. Besides, a further survey of the fungal-bacterial cross-talk indicated that the production of co-culture-induced diphenyl ethers by fungi might result from the fungal response against the secretion of surfactins by bacteria in the cross-talk. This study demonstrated that the presented co-culture device and the metabolomic routine would facilitate the investigation on chemically mediated interactions in nature as well as cryptic natural products discovery.


Assuntos
Antibacterianos/metabolismo , Antibiose/fisiologia , Produtos Biológicos/metabolismo , Fungos/metabolismo , Klebsiella pneumoniae/metabolismo , Metabolismo Secundário/fisiologia , Cromatografia Líquida , Técnicas de Cocultura/instrumentação , Técnicas de Cocultura/métodos , Ecossistema , Fungos/crescimento & desenvolvimento , Klebsiella pneumoniae/crescimento & desenvolvimento , Espectrometria de Massas , Metabolômica/métodos
5.
Org Biomol Chem ; 15(5): 1155-1163, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28074949

RESUMO

Three new quinazoline derivatives (1-3), one new oxepin-containing natural product (4) and four new cyclopenin derivatives (5-7 and 9) have been isolated from an EtOAc extract of the Taiwan Kueishantao hydrothermal vent crab-associated fungus Aspergillus versicolor XZ-4. Their planar structures were established by HRMS, 1D and 2D NMR spectroscopic data analyses. The absolute configurations for compounds 1 and 4 were determined by chiral phase HPLC analysis of their hydrolysis products. The absolute configurations of 2, 3 and 7 were defined mainly by comparison of the quantum chemical TDDFT calculated and the experimental ECD spectra, and the absolute configuration of 5 was deduced from comparison of the optical rotation values reported in the literature. The presence of two atropisomers of 5 was established by NOE analyses. The Ile & Val units in compounds 1-3 allowed the assignment of a new quinazoline skeleton and it's the first time the configuration of isoleucine in the quinazoline skeleton was defined. A series of 7-methoxy cyclopenin derivatives were reported for the first time in this study. The bioevaluation of compounds 5, 7, 8 and 9 revealed inhibitory activities against E. coli at MIC values around 32 µg mL-1.


Assuntos
Antibacterianos/farmacologia , Aspergillus/química , Produtos Biológicos/farmacologia , Escherichia coli/efeitos dos fármacos , Oxepinas/farmacologia , Quinazolinas/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Benzodiazepinonas/química , Benzodiazepinonas/isolamento & purificação , Benzodiazepinonas/farmacologia , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Oxepinas/química , Oxepinas/isolamento & purificação , Quinazolinas/química , Quinazolinas/isolamento & purificação , Relação Estrutura-Atividade
6.
Appl Microbiol Biotechnol ; 101(4): 1395-1408, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27730337

RESUMO

Marine hydrothermal microorganisms respond rapidly to the changes in the concentrations and availability of metals within hydrothermal vent microbial habitats which are strongly influenced by elevated levels of heavy metals. Most hydrothermal vent actinomycetes possess a remarkable capability for the synthesis of a broad variety of biologically active secondary metabolites. Major challenges in the screening of these microorganisms are to activate the expression of cryptic biosynthetic gene clusters and the development of technologies for efficient dereplication of known compounds. Here, we report the identification of a novel antibiotic produced by Streptomyces sp. WU20 isolated from the metal-rich hydrothermal vents in Taiwan Kueishantao, following a strategy based on metal induction of silent genes combined with metabolomics analytical methods. HPLC-guided isolation by tracking the target peak resulted in the characterization of the novel compound 1 with antimicrobial activity against Bacillus subtilis. The stress metabolite 1 induced by nickel is structurally totally different compared with the normally produced compounds. This study underlines the applicability of metal induction combined with metabolic analytical techniques in accelerating the exploration of novel antibiotics and other medically relevant natural products.


Assuntos
Antibacterianos/metabolismo , Fontes Hidrotermais/microbiologia , Streptomyces/metabolismo , Actinobacteria/metabolismo , Metabolômica/métodos
7.
Mar Drugs ; 14(8)2016 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-27548192

RESUMO

A new verrucosidin derivative, methyl isoverrucosidinol (1), was isolated from the marine fungus Penicillium sp. Y-50-10, dwelling in sulfur rich sediment in the Kueishantao hydrothermal vents off Taiwan. The structure was established by spectroscopic means including HRMS and 2D-NMR spectroscopic analysis. The absolute configuration was defined mainly by comparison of quantum chemical TDDFT calculated and experimental ECD spectra. Among hitherto known compounds with a verrucosidine backbone isolated from natural resource, compound 1 represents the first example of a new conformational isomer of its skeleton, exhibiting antibiotic activity against Bacillus subtilis with MIC value 32 µg/mL.


Assuntos
Antibacterianos/química , Organismos Aquáticos/química , Fontes Hidrotermais/microbiologia , Penicillium/química , Pironas/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Isomerismo , Testes de Sensibilidade Microbiana , Conformação Molecular , Ressonância Magnética Nuclear Biomolecular , Pironas/isolamento & purificação , Pironas/farmacologia , Taiwan
8.
Molecules ; 21(1): 105, 2016 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-26784166

RESUMO

A novel hybrid polyketide-terpenoid, aspergstressin (1), possessing a unique fused polycyclic structure, was induced from culture broth of strain Aspergillus sp. WU 243 by cobalt ion stimulation. The strain was isolated from the digestive gland of Xenograpsus testudinatus, a unique type of crab which dwells in the Kueishantao hydrothermal vents off Taiwan. The chemical structure and relative configuration of the stress metabolite were established by spectroscopic means. Aspergillus sp. WU 243 produced aspergstressin (1) only under cobalt stressed culture conditions. The results show that stress-driven discovery of new natural products from hydrothermal vent fungi is an effective strategy to unveil the untapped reservoir of small molecules from species found in the hydrothermal vent environment.


Assuntos
Aspergillus/efeitos dos fármacos , Cobalto/farmacologia , Policetídeos/isolamento & purificação , Terpenos/isolamento & purificação , Animais , Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Braquiúros/microbiologia , Cátions Bivalentes , Meios de Cultura/química , Meios de Cultura/farmacologia , Fontes Hidrotermais , Policetídeos/química , Policetídeos/metabolismo , Água do Mar , Estresse Fisiológico , Taiwan , Terpenos/química , Terpenos/metabolismo
9.
Arch Phys Med Rehabil ; 96(12): 2096-102, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26360975

RESUMO

OBJECTIVE: To use Nintendo's Wii Fit balance board to determine the effectiveness of exergaming training in reducing risk and incidence of falls in older adults with a history of falls. DESIGN: Randomized controlled trial. SETTING: Nursing home for older adults. PARTICIPANTS: Adults aged 65 years and older (N=60). INTERVENTIONS: Participants who lived in a nursing home had 6 weeks of balance training with either Wii Fit equipment or conventional exercise. MAIN OUTCOME MEASURES: Physiological Profile Assessment scores and incidence of falls were observed with subsequent intention-to-treat statistical analyses. RESULTS: Physiological Profile Assessment scores and incidence of falls improved significantly in both groups after the intervention (all P<.01), but participants in the Wii Fit training group showed a significantly greater improvement in both outcome measures (P=.004 and P<.001, respectively). CONCLUSIONS: In institutionalized older adults with a history of falls, Wii Fit balance training was more effective than conventional balance training in reducing the risk and incidence of falls.


Assuntos
Acidentes por Quedas/prevenção & controle , Terapia por Exercício/métodos , Idoso Fragilizado , Equilíbrio Postural , Jogos de Vídeo , Idoso , Idoso de 80 Anos ou mais , Feminino , Instituição de Longa Permanência para Idosos , Humanos , Incidência , Masculino , Casas de Saúde , Comportamento de Redução do Risco
10.
Mar Drugs ; 12(6): 3203-17, 2014 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-24879544

RESUMO

A naturally new cyclopeptide, clavatustide C, was produced as a stress metabolite in response to abiotic stress elicitation by one of the hydrothermal vent fluid components Zn in the cultured mycelia of Aspergillus clavatus C2WU, which were isolated from Xenograpsus testudinatus. X. testudinatus lives at extreme, toxic habitat around the sulphur-rich hydrothermal vents in Taiwan Kueishantao. The known compound clavatustide B was also isolated and purified. This is the first example of a new hydrothermal vent microbial secondary metabolite produced in response to abiotic Zn treatment. The structures were established by spectroscopic means. The regulation of G1-S transition in hepatocellular carcinoma cell lines by clavatustide B was observed in our previous study. The purpose of the present study was to verify these results in other types of cancer cell lines and elucidate the possible molecular mechanism for the anti-cancer activities of clavatustide B. In different human cancer cell lines, including pancreatic cancer (Panc-1), gastric cancer (MGC-803), colorectal cancer (SW-480), retinoblastoma (WERI-Rb-1) and prostate cancer (PC3), clavatustide B efficiently suppressed cell proliferations in a dose-dependent manner. Although different cancer cell lines presented variety in Max effect dose and IC50 dose, all cancer cell lines showed a lower Max effect dose and IC50 dose compared with human fibroblasts (hFB) (p < 0.05). Moreover, significant accumulations in G1 phases and a reduction in S phases (p < 0.05) were observed under clavatustide B treatment. The expression levels of 2622 genes including 39 cell cycle-associated genes in HepG2 cells were significantly altered by the treatment with 15 µg/mL clavatustide B after 48 h. CCNE2 (cyclin E2) was proved to be the key regulator of clavatustide B-induced G1-S transition blocking in several cancer cell lines by using real-time PCR.


Assuntos
Aspergillus/metabolismo , Braquiúros/microbiologia , Depsipeptídeos/farmacologia , Peptídeos Cíclicos/isolamento & purificação , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Aspergillus/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclinas/metabolismo , Depsipeptídeos/química , Depsipeptídeos/isolamento & purificação , Relação Dose-Resposta a Droga , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fase G1/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Fontes Hidrotermais/microbiologia , Concentração Inibidora 50 , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Peptídeos Cíclicos/química , Reação em Cadeia da Polimerase em Tempo Real , Fase S/efeitos dos fármacos , Taiwan , Zinco/química
11.
Mar Drugs ; 11(12): 4761-72, 2013 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-24317468

RESUMO

Two novel cyclodepsipeptides containing an unusual anthranilic acid dimer and a D-phenyllactic acid residues, clavatustides A and B, were identified from cultured mycelia and broth of Aspergillus clavatus C2WU isolated from Xenograpsus testudinatus, which lives at extreme, toxic habitat around the sulphur-rich hydrothermal vents in Taiwan Kueishantao. This is the first example of cyclopeptides containing an anthranilic acid dimer in natural products, and the first report of microbial secondary metabolites from the hydrothermal vent crab. Clavatustides A and B suppressed the proliferation of hepatocellular carcinoma (HCC) cell lines (HepG2, SMMC-7721 and Bel-7402) in a dose-dependent manner, and induced an accumulation of HepG2 cells in G1 phase and reduction of cells in S phase.


Assuntos
Aspergillus/química , Aspergillus/metabolismo , Braquiúros/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Depsipeptídeos/farmacologia , Fase G1/efeitos dos fármacos , Fase S/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Hep G2 , Humanos , Fontes Hidrotermais , Neoplasias Hepáticas/tratamento farmacológico , ortoaminobenzoatos/química , ortoaminobenzoatos/farmacologia
12.
Data Brief ; 51: 109758, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38053585

RESUMO

The Fukushima accident released short-lived Cs-134 and longer-lived Cs-137 to the ocean. The amount, although substantial, is much less than that produced during the atomic bomb tests 60 yrs ago. Cs-134 and Cs-137 are anthropogenic radionuclides and soluble in seawater; hence, the radioactivity can be used as a tracer for special events or currents. Samples of Cs-134 and Cs-137 in seawater were collected around Taiwan, including the Kuroshio, the northern South China Sea, the Taiwan Strait, and the southern East China Sea from 2018 to 2021. The average surface Cs-137 activity was 1.18±0.25 Bq m - 3, and the activities of Cs-134 samples were all under the detection limit. Complete data are archived, including sampling date, location, water depth, temperature, salinity, and Cs-137 activity; the total sample amount is 577.

13.
Microbiome ; 11(1): 270, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38049915

RESUMO

BACKGROUND: Active hydrothermal vents create extreme conditions characterized by high temperatures, low pH levels, and elevated concentrations of heavy metals and other trace elements. These conditions support unique ecosystems where chemolithoautotrophs serve as primary producers. The steep temperature and pH gradients from the vent mouth to its periphery provide a wide range of microhabitats for these specialized microorganisms. However, their metabolic functions, adaptations in response to these gradients, and coping mechanisms under extreme conditions remain areas of limited knowledge. In this study, we conducted temperature gradient incubations of hydrothermal fluids from moderate (pH = 5.6) and extremely (pH = 2.2) acidic vents. Combining the DNA-stable isotope probing technique and subsequent metagenomics, we identified active chemolithoautotrophs under different temperature and pH conditions and analyzed their specific metabolic mechanisms. RESULTS: We found that the carbon fixation activities of Nautiliales in vent fluids were significantly increased from 45 to 65 °C under moderately acidic condition, while their heat tolerance was reduced under extremely acidic conditions. In contrast, Campylobacterales actively fixed carbon under both moderately and extremely acidic conditions under 30 - 45 °C. Compared to Campylobacterales, Nautiliales were found to lack the Sox sulfur oxidation system and instead use NAD(H)-linked glutamate dehydrogenase to boost the reverse tricarboxylic acid (rTCA) cycle. Additionally, they exhibit a high genetic potential for high activity of cytochrome bd ubiquinol oxidase in oxygen respiration and hydrogen oxidation at high temperatures. In terms of high-temperature adaption, the rgy gene plays a critical role in Nautiliales by maintaining DNA stability at high temperature. Genes encoding proteins involved in proton export, including the membrane arm subunits of proton-pumping NADH: ubiquinone oxidoreductase, K+ accumulation, selective transport of charged molecules, permease regulation, and formation of the permeability barrier of bacterial outer membranes, play essential roles in enabling Campylobacterales to adapt to extremely acidic conditions. CONCLUSIONS: Our study provides in-depth insights into how high temperature and low pH impact the metabolic processes of energy and main elements in chemolithoautotrophs living in hydrothermal ecosystems, as well as the mechanisms they use to adapt to the extreme hydrothermal conditions. Video Abstract.


Assuntos
Epsilonproteobacteria , Fontes Hidrotermais , Ecossistema , Temperatura , Prótons , Carbono/metabolismo , DNA , Fontes Hidrotermais/microbiologia , Filogenia
14.
Microbiome ; 10(1): 170, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36242065

RESUMO

BACKGROUND: Geothermal systems have contributed greatly to both our understanding of the functions of extreme life and the evolutionary history of life itself. Shallow-sea hydrothermal systems are ecological intermediates of deep-sea systems and terrestrial springs, harboring unique and complexed ecosystems, which are well-lit and present physicochemical gradients. The microbial communities of deep-sea and terrestrial geothermal systems have been well-studied at the population genome level, yet little is known about the communities inhabiting the shallow-sea hydrothermal systems and how they compare to those inhabiting other geothermal systems. RESULTS: Here, we used genome-resolved metagenomic and metaproteomic approaches to probe into the genetic potential and protein expression of microorganisms from the shallow-sea vent fluids off Kueishantao Island. The families Nautiliaceae and Campylobacteraceae within the Epsilonbacteraeota and the Thiomicrospiraceae within the Gammaproteobacteria were prevalent in vent fluids over a 3-year sampling period. We successfully reconstructed the in situ metabolic modules of the predominant populations within the Epsilonbacteraeota and Gammaproteobacteria by mapping the metaproteomic data back to metagenome-assembled genomes. Those active bacteria could use the reductive tricarboxylic acid cycle or Calvin-Benson-Bassham cycle for autotrophic carbon fixation, with the ability to use reduced sulfur species, hydrogen or formate as electron donors, and oxygen as a terminal electron acceptor via cytochrome bd oxidase or cytochrome bb3 oxidase. Comparative metagenomic and genomic analyses revealed dramatic differences between submarine and terrestrial geothermal systems, including microbial functional potentials for carbon fixation and energy conversion. Furthermore, shallow-sea hydrothermal systems shared many of the major microbial genera that were first isolated from deep-sea and terrestrial geothermal systems, while deep-sea and terrestrial geothermal systems shared few genera. CONCLUSIONS: The metabolic machinery of the active populations within Epsilonbacteraeota and Gammaproteobacteria at shallow-sea vents can mirror those living at deep-sea vents. With respect to specific taxa and metabolic potentials, the microbial realm in the shallow-sea hydrothermal system presented ecological linkage to both deep-sea and terrestrial geothermal systems. Video Abstract.


Assuntos
Epsilonproteobacteria , Gammaproteobacteria , Fontes Hidrotermais , Microbiota , Citocromos/genética , Citocromos/metabolismo , Epsilonproteobacteria/genética , Formiatos/metabolismo , Gammaproteobacteria/genética , Gammaproteobacteria/metabolismo , Humanos , Hidrogênio/metabolismo , Fontes Hidrotermais/microbiologia , Oxirredutases , Oxigênio/metabolismo , Filogenia , Enxofre/metabolismo
15.
Mar Pollut Bull ; 182: 114026, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35963224

RESUMO

The Fukushima accident released short-lived Cs-134 and longer-lived Cs-137 to the ocean. The amount, although substantial, is much less than that produced during the atomic bomb tests 60 years ago. But, the latter has received little attention. Here we found only Cs-137 in waters near the origin of the Kuroshio. The speed of the Kuroshio current generally decreases with water depth, yet, the Cs-137 activity increases with depth to reach a subsurface maximum of 2.4 Bq m-3. As a result, a core of high Cs-137 flux, or a radiocesium stream, exists at approximately 200-400 m in depth. In total, the Kuroshio transports about 1 PBq year-1 Cs-137 northward between 121 and 123°E, 1000 times more than the 0.73-1.0 TBq year-1 discharged to the ocean at Fukushima in 2016-2018.


Assuntos
Acidente Nuclear de Fukushima , Monitoramento de Radiação , Poluentes Radioativos da Água , Radioisótopos de Césio/análise , Japão , Rios , Poluentes Radioativos da Água/análise
16.
Sci Rep ; 11(1): 5080, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33658632

RESUMO

The Kuroshio-literally "the Black Stream"-is the most substantial current in the Pacific Ocean. It was called the Black Stream because this oligotrophic current is so nutrient-poor in its euphotic zone that the water appears black without the influence of phytoplankton and the associated, often colored dissolved organic matter. Yet, below the euphotic layer, nutrient concentrations increase with depth while current speed declines. Consequently, a core of maximum nutrient flux, the so-called nutrient stream, develops at a depth of roughly between 200 and 800 m. This poorly studied nutrient stream transports nutrients to and supports high productivity and fisheries on the East China Sea continental shelf; it also transports nutrients to and promotes increased productivity and fisheries in the Kuroshio Extension and the subarctic Pacific Ocean. Three modes of the Kuroshio nutrient stream are detected off SE Taiwan for the first time: one has a single-core; one has two cores that are apparently separated by the ridge at 120.6-122° E, and one has two cores that are separated by a southward flow above the ridge. More importantly, northward nutrient transports seem to have been increasing since 2015 as a result of a 30% increase in subsurface water transport, which began in 2013. Such a nutrient stream supports the Kuroshio's high productivity, such as on the East China Sea continental shelf and in the Kuroshio Extension SE of Japan.

17.
Sci Rep ; 11(1): 307, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33431993

RESUMO

The La Niña of 2007/2008 was particularly strong, so was the southward flow of the cold, nutrient-rich Changjiang (Yangtze River) Diluted Water (CDW) when the winter monsoon started to blow in the fall. Here we use shipboard data in 2008 in two transects, one in the southwestern East China Sea and one in the southern Taiwan Strait, to show that as late as April in 2008 the CDW was still clearly identifiable when the winter monsoon had weakened. Waters as cold as 16 °C with a salinity lower than 30 still occupied the southwestern East China Sea. Waters of 17 °C and S < 32 could also be found off the coast of China in the central Taiwan Strait. The concentration of NO3 + NO2 was higher than 18 µmol L-1 at both places, which was as much as 40 times higher than the northward moving South China Sea (SCS) water to the east. As a result, the Changjiang River plume may be a significant source of nutrients, particularly N, to the oligotrophic, N-poor SCS, especially in the La Niña years. Indeed, colder and more turbid CDW was more intense and went farther south in 2008 compared with the normal springs of 2006, 2007 and 2009.

18.
Data Brief ; 37: 107216, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34189205

RESUMO

This paper presents data on carbon and nitrogen stable isotopes in benthos from shallow-water hydrothermal vents (SV) and nearby non-vent rocky reefs (NV) located in northeastern Taiwan, which is related to the article "Isotopic niche differentiation in benthic consumers from shallow-water hydrothermal vents and nearby non-vent rocky reefs in northeastern Taiwan" [1]. Field sampling work was conducted in July 2009 and July-August 2010 to collect sediment organic matters (SOM), zooplankton, and benthos for carbon and nitrogen stable isotopic analyses. Scuba divers collected macrobenthos, seawater, and surface sediments (0-2 cm). The collection of zooplankton was by a North Pacific standard net and trawled vertically. Testing samples were lyophilized before grounding by a mortar and pestle. For carbon and nitrogen isotope analyses, approximately 1 mg of powder was weighed and encapsulated in a tin capsule. Analyses were performed at the stable isotope laboratory at the University of California at Davis using an Integra Mass Spectrometer elemental analyzer (PDZ Europa, Sandbach, UK). The information is presented as 187 and 53 unprocessed data points from SV and NV, which incorporates δ13C and δ15N values (‰) of sediment, zooplankton, and benthos' tissue samples. Data from SOM provides information about chemosynthetic activity in SV sites. These data can be used to correlate food sources of consumers inhabiting shallow-water hydrothermal vent and rocky reef ecosystems in subtropical regions.

19.
Mar Pollut Bull ; 167: 112354, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33866201

RESUMO

In this article dissolved oxygen results of research cruises through the Persian Gulf during 2018-2019 are discussed. The results showed that summer to autumn hypoxia occurred mainly at depths ≥ 50 m to the bottom. This seasonal hypoxia started in late summer reaching its greatest severity in mid-autumn with an area of 50,000 km2 in the Persian Gulf. The minimum oxygen measured at the near-bottom layer of the western basin in autumn (25.8 µmol/kg) was lower than any previous measurement in the open waters of the Persian Gulf. In the Strait of Hormuz, the seasonal hypoxia appeared in summer in the near bottom of the most eastern part at the Iranian side. pHT values recorded in hypoxic waters were as low as what is predicted for surface ocean under ocean acidification in 2100. Considering the results, we suggest evaluating the effects of hypoxia and acidification on the Persian Gulf ecosystems.


Assuntos
Ecossistema , Monitoramento Ambiental , Humanos , Concentração de Íons de Hidrogênio , Hipóxia , Oceano Índico , Irã (Geográfico) , Água do Mar
20.
Sci Total Environ ; 798: 149214, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34333434

RESUMO

Seven cruises were carried out in a bay scallop (Argopecten irradians) farming area and its surrounding waters, North Yellow Sea, from March to November 2017 to study the dynamics of the carbonate system and its controlling factors. Results indicated that the studied parameters were highly variability over a range of spatiotemporal scales, comprehensively forced by various physical and biological processes. Mixing effect and scallop calcification played the most important role in the seasonal variation of total alkalinity (TAlk). For dissolved inorganic carbon (DIC), in addition to mixing, air-sea exchange and microbial activity, e.g. photosynthesis and microbial respiration processes, had more important effects on its dynamics. Different from the former, the changes of water pHT, partial pressure of CO2 (pCO2) and aragonite saturation state (ΩA) were mainly controlled by the combining of the temperature, air-sea exchange, microbial activity and scallop metabolic activities. In addition, the results indicated that massive scallop farming can significantly increase the DIC/TAlk ratio by reducing the TAlk concentration in seawater, thereby reducing the buffering capacity of the carbonate system in seawater especially for ΩA. Preliminary calculated, ~75.7 and ~45.5 µmol kg-1 of TAlk were removed from the surface and bottom waters respectively in one scallop cultivating cycle. If these carbonates cannot be replenished in time, it is likely to accelerate the acidification process of coastal waters. This study highlighted the control mechanism of the carbonate system under the influence of bay scallop farming, and provided useful information for revealing the potential link between human activities (shelled-mollusc mariculture) and coastal acidification.


Assuntos
Carbonatos , Pectinidae , Agricultura , Animais , Carbonatos/análise , China , Humanos , Concentração de Íons de Hidrogênio , Água do Mar , Frutos do Mar
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