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1.
Nat Commun ; 15(1): 5009, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38866778

RESUMEN

A positive Indian Ocean Dipole features an anomalously high west-minus-east sea surface temperature gradient along the equatorial Indian Ocean, affecting global extreme weathers. Whether the associated impact spills over to global economies is unknown. Here, we develop a nonlinear and country-heterogenous econometric model, and find that a typical positive event causes a global economic loss that increases for further two years after an initial shock, inducing a global loss of hundreds of billion US dollars, disproportionally greater to the developing and emerging economies. The loss from the 2019 positive event amounted to US$558B, or 0.67% in global economic growth. Benefit from a negative dipole event is far smaller. Under a high-emission scenario, a projected intensification in Dipole amplitude causes a median additional loss of US$5.6 T at a 3% discount rate, but likely as large as US$24.5 T. The additional loss decreases by 64% under the target of the Paris Agreement.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38754749

RESUMEN

OBJECTIVE: The mechanism of left ventricular outflow tract obstruction (LVOTO) is complex in hypertrophic cardiomyopathy (HCM). We aimed to evaluate the impact of mitral valve geometry on LVOTO by echocardiography. MATERIALS AND METHODS: The study population comprised 177 consecutive patients with HCM. Morphological findings of left ventricular hypertrophy and LVOTO-related abnormalities were assessed by comprehensive transthoracic echocardiography. Aortomitral angle, mitral leaflet length, and coaptation height were measured and analyzed at rest. Multivariable stepwise forward logistic regression analysis was performed to identify geometric predictors of LVOTO. RESULTS: One hundred thirty-seven patients had an LVOT gradient ≥30 mm Hg. Multivariable logistic regression showed that aortomitral angle (odds ratio [OR], 0.89; 95% CI, 0.83-0.95, P < .001), coaptation height (OR, 1.96; 95% CI, 1.41-2.72, P < .001), and accessory mitral valve chordae tendineae (OR, 13.1; 95% CI, 4.32-39.95; P < .001) were independently associated with LVOTO. Receiver operating characteristic analysis showed that the area under the curve of mitral coaptation height was higher (area under the curve = 0.815) than the other 2 indicators (P < .05). CONCLUSION: Mitral coaptation height, aortomitral angle, and accessory mitral valve chordae tendineae were important predictors of SAM and LVOTO in HCM independent of septal hypertrophy.

3.
Nat Commun ; 15(1): 4370, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38778056

RESUMEN

El Niño-Southern Oscillation (ENSO) is the dominant mode of interannual climate variability in the tropical Pacific, whose nature nevertheless may change significantly in a warming climate. Here, we show that the predictability of ENSO may decrease in the future. Across the models in the Coupled Model Intercomparison Project Phase 6 (CMIP6), we find a robust decrease of the persistence and predictability for the Central Pacific (CP) ENSO under global warming, notably in passing through the boreal spring. The strength of spring predictability barrier will be increased by 25% in the future. The reduced predictability of CP ENSO is caused by the faster warming over surface ocean in tropical Pacific and, in turn, the enhanced thermodynamical damping rate on CP ENSO in response to global warming. In contrast, the predictability of Eastern Pacific ENSO will not change. Our results suggest that future greenhouse warming will make the prediction of CP ENSO more challenging, with far-reaching implications on future climate predictions.

4.
Nat Commun ; 15(1): 2832, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38565534

RESUMEN

Large-scale marine heatwaves in the Northeast Pacific (NEP), identified here and previously as 'warm blobs', have devastating impacts on regional ecosystems. An anomalous atmospheric ridge over the NEP is known to be crucial for maintaining these warm blobs, also causing abnormally cold temperatures over North America during the cold season. Previous studies linked this ridge to teleconnections from tropical sea surface temperature anomalies. However, it was unclear whether teleconnections from the extratropics could also contribute to the ridge. Here we show that planetary wave trains, triggered by increased rainfall and latent heat release over the Mediterranean Sea accompanied by decreased rainfall over the North Atlantic, can transport wave energy to the NEP, guided by the westerly jet, and induce a quasi-barotropic ridge there. Our findings provide insights into extratropical teleconnections sustaining the NEP ridge, offering a source of potential predictability for the warm blobs and temperature fluctuations over North America.

5.
Am J Transl Res ; 15(11): 6514-6523, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38074833

RESUMEN

OBJECTIVE: To investigate the efficacy of ganciclovir in the treatment of cytomegalovirus (CMV) infection in infants and its effect on inflammatory reaction and immune function. METHODS: In this retrospective analysis, from January 2019 to December 2022, a total of 100 infants with CMV infection were collected from the Department of Pediatrics of Anhui Maternal and Child Health Hospital and divided into two groups (50 in each group) based on differences in intervention methods. The control group (CG) was given routine treatment and antiviral therapy, and the observation group (OG) was additionally given intravenous drip of 5-6 mg/kg ganciclovir on the basis of routine treatment given to the CG. After 21 d of treatment, the clinical efficacy, inflammatory factor levels, immunoglobulin levels, T-lymphocyte levels and incidence of adverse reactions of both groups were observed and compared. RESULTS: After treatment, the overall response rate in the OG (92.00%) was significantly higher than that in the CG (76.00%) (P = 0.029). The OG after treatment displayed significantly lower levels of tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) (P = 0.006, P = 0.000), but significantly higher level of interleukin 10 (IL-10) than CG (P = 0.000). Compared with CG, levels of immunoglobulin G (IgG), immunoglobulin A (IgA), immunoglobulin M (IgM), CD3+, CD4+ and CD4+/CD8+ in the OG increased significantly (P = 0.048, P = 0.000, P = 0.000, P = 0.000, P = 0.000, P = 0.000), whereas level of CD8+ decreased significantly (P = 0.000) after treatment. No significant difference in the incidence of adverse reactions between the two groups was observed (P > 0.05). CONCLUSION: Intervention of ganciclovir can effectively treat CMV infection in infants, reduce the inflammatory reactions and enhance the immune function of the body, without increasing the incidence of adverse reactions.

6.
PLoS One ; 18(11): e0287799, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37917716

RESUMEN

Necrotizing enterocolitis (NEC) is a severe intestinal disease of the newborn infants, associated with high morbidity and mortality. It has been reported that Bifidobacterium could protect the intestinal barrier function and reduce the risk of NEC. This study aimed to evaluate the probiotic potential of Bifidobacterium strains isolated from the chicken intestines and its effect on necrotizing enterocolitis in newborn SD rats. Out of 32 isolates, B. breve AHC3 not only exhibited excellent probiotic potential, including tolerance to artificial simulated gastric conditions, adhesion to HT-29 cells, antioxidant capacity and antibacterial activity, but also possessed reliable safety. Additionally, NEC model was established to further investigate the effect of B. breve AHC3 on necrotizing enterocolitis in newborn SD rats. It was illustrated that administration of B. breve AHC3 significantly not only reduced the incidence of NEC (from 81.25% to 34.38%) (P< 0.05), but also alleviated the severity of ileal injury (P< 0.05). Compared with NEC model, B. breve AHC3 could significantly decrease the level of proinflammatory factor TNF-α (P< 0.05) and increase the level of antiinflammatory factor IL-10 (P< 0.05) in the ileum of NEC rats. Through the intervention of B. breve AHC3, the gray value of inducible nitric oxide synthase (iNOS) in intestinal tissue of NEC rats was significantly reduced (P< 0.05). It was indicated that B. breve AHC3 exhibited prominent probiotic potential and reliable safety. In the neonatal SD rat model of NEC, B. breve AHC3 had an available protective effect on the intestinal injury of NEC, which might be related to reducing the inflammatory reaction in the ileum and inhibiting the expression of iNOS in intestinal tissue cells. B. breve AHC3 could be used as a potential treatment for human NEC.


Asunto(s)
Bifidobacterium breve , Enterocolitis Necrotizante , Enfermedades del Recién Nacido , Probióticos , Lactante , Recién Nacido , Ratas , Animales , Humanos , Pollos , Enterocolitis Necrotizante/metabolismo , Ratas Sprague-Dawley , Intestinos/microbiología , Probióticos/farmacología , Probióticos/uso terapéutico , Bifidobacterium , Animales Recién Nacidos , Modelos Animales de Enfermedad
7.
Nat Commun ; 14(1): 5887, 2023 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-37735448

RESUMEN

The El Niño-Southern Oscillation (ENSO) is a consequential climate phenomenon affecting global extreme weather events often with largescale socioeconomic impacts. To what extent the impact affects the macroeconomy, how long the impact lasts, and how the impact may change in a warming climate are important questions for the field. Using a smooth nonlinear climate-economy model fitted with historical data, here we find a damaging impact from an El Niño which increases for a further three years after initial shock, amounting to multi-trillion US dollars in economic loss; we attribute a loss of US$2.1 T and US$3.9 T globally to the 1997-98 and 2015-16 extreme El Niño events, far greater than that based on tangible losses. We find impacts from La Niña are asymmetric and weaker, and estimate a gain of only US$0.06 T from the 1998-99 extreme La Niña event. Under climate change, economic loss grows exponentially with increased ENSO variability. Under a high-emission scenario, increased ENSO variability causes an additional median loss of US$33 T to the global economy at a 3% discount rate aggregated over the remainder of the 21st century. Thus, exacerbated economic damage from changing ENSO in a warming climate should be considered in assessments of mitigation strategies.

8.
Natl Sci Rev ; 10(6): nwad069, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37181085

RESUMEN

With the aid of the newly developed 'Sunway' heterogeneous-architecture supercomputer, which has world-leading HPC (high-performance computer) capability, a series of high-resolution coupled Earth system models (SW-HRESMs) with up to 5 km of atmosphere and 3 km of ocean have been developed. These models can meet the needs of multiscale interaction studies with different computational costs. Here we describe the progress of SW-HRESMs development, with an overview of the major advancements made by the international Earth science community in HR-ESMs. We also show the preliminary results of SW-HRESMs with regard to capturing major weather-climate extremes in the atmosphere and ocean, stressing the importance of permitted clouds and ocean submesoscale eddies in modeling tropical cyclones and eddy-mean flow interactions, and paving the way for further model development to resolve finer scales with even higher resolution and more realistic physics. Finally, in addition to increasing model resolution, the development procedure for a non-hydrostatic cloud and ocean submesoscale resolved ESM is discussed, laying out the major scientific directions of such a huge modeling advancement.

9.
Sci Total Environ ; 874: 162433, 2023 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-36841405

RESUMEN

Heavy pollution events of fine particulate matter (PM2.5) frequently occur in China, seriously affecting the human health. However, how meteorological factors and anthropogenic emissions affect PM2.5 and the major constituents, as well as the subsequent health effect, remains unclear. Here, based on regional climate and air quality models Weather Research and Forecasting (WRF) and Community Multiscale Air Quality (CMAQ), the PM2.5 and major constituents in China at present and mid-century under the carbon neutral scenario Shared Socioeconomic Pathways (SSP)1-2.6 are simulated. Due to anthropogenic emission reduction, concentrations of PM2.5 and the constituents decrease substantially in SSP1-2.6. The long-term exposure premature deaths at present are 2.23 million per year in mainland China, which is projected to increase by 76 % under SSP1-2.6 despite emission reduction, primarily attributable to aging which strikingly offsets the effect of air quality improvement. The number of annual premature deaths resulting from short-term exposure is 228,104 in mainland China at present, which is projected to decrease in the future. Using North China Plain as an example, we identify that among the major constituents of PM2.5, organic carbon leads to the most short-term exposure deaths considering the largest exposure-response coefficient. Regarding the abnormally meteorological conditions, we find, relative to low relative humidity (RH) and non-stagnation, the compound events, defined as concurrence of high RH and atmospheric stagnation, exhibit an amplified role inducing larger premature deaths compared to the additive effect of the individual event of high RH and atmospheric stagnation. This nonlinear effect occurs at both present and future, but diminished in future due to emission reductions. Our study highlights the importance of considering both the long- and short-term premature deaths associated with PM2.5 and the constituents, as well as the critical effect of extreme weather events.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Humanos , Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Contaminación del Aire/análisis , China , Predicción
10.
Ann Transl Med ; 10(7): 420, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35530953

RESUMEN

Background: The hospitalization for asthma exacerbation has varied with seasons, however, the underlying weather reasons have not been fully explored yet. This study is aimed to explore the effect of weather factors on increased number of hospitalization due to worsening of asthma symptoms. This will provide more information to the relevant authorities to allocate appropriate medical resources as per the weather conditions in Qingdao, China. Methods: All adult patients admitted for asthma exacerbation from 1 January, 2017 to 31 December, 2019 were enrolled from 13 main hospitals of Qingdao. The clinical data, including age, sex, smoking history, etc., were collected from the electronic medical record (EMR) systems. The hourly air quality of Qingdao from 2017-2019, including the air quality index (AQI), PM2.5 and PM10, was obtained from the China National Environmental Monitoring Centre. All these parameters during 2017-2019 were compared monthly. For meteorological data, the monthly horizontal wind at 850 hPa and vertical velocity at 500 hPa during 1960-2020 were obtained from National Center for Environmental Prediction (NCEP) and the National Center for Atmospheric Research (NCAR) global reanalysis dataset. The correlation analysis was applied to determine the association between asthma hospitalizations and the environmental factors, including atmospheric pressure, humidity, vertical visibility, and etc., monthly. Results: In all, 10,549 asthmatic inpatients (45.7% males, 54.3% females) were included in the study. The inpatients number for asthma exacerbation had a plateau lasting from March to June of 2019, accompanied with high PM2.5 and PM10, as well as bad air quality from January to March of 2019, potentially governed by the El Niño event in 2018. However, there was no significance correlation between the number of asthma hospitalizations and the average value of all environmental factors. Conclusions: The high rate of hospitalization for asthma exacerbation in Qingdao during the spring of 2019 was associated with the unfavorable weather conditions, which might be linked to the atmospheric circulation in East Asia.

11.
Science ; 374(6563): eaay9165, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34591645

RESUMEN

Climate variability in the tropical Pacific affects global climate on a wide range of time scales. On interannual time scales, the tropical Pacific is home to the El Niño­Southern Oscillation (ENSO). Decadal variations and changes in the tropical Pacific, referred to here collectively as tropical Pacific decadal variability (TPDV), also profoundly affect the climate system. Here, we use TPDV to refer to any form of decadal climate variability or change that occurs in the atmosphere, the ocean, and over land within the tropical Pacific. "Decadal," which we use in a broad sense to encompass multiyear through multidecadal time scales, includes variability about the mean state on decadal time scales, externally forced mean-state changes that unfold on decadal time scales, and decadal variations in the behavior of higher-frequency modes like ENSO.

12.
Sci Bull (Beijing) ; 65(21): 1849-1858, 2020 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36659125

RESUMEN

A regional coupled prediction system for the Asia-Pacific (AP-RCP) (38°E-180°, 20°S-60°N) area has been established. The AP-RCP system consists of WRF-ROMS (Weather Research and Forecast, and Regional Ocean Model System) coupled models combined with local observational information through dynamically downscaling coupled data assimilation (CDA). The system generates 18-day forecasts for the atmosphere and ocean environment on a daily quasi-operational schedule at Pilot National Laboratory for Marine Science and Technology (Qingdao) (QNLM), consisting of 2 different-resolution coupled models: 27 km WRF coupled with 9 km ROMS, 9 km WRF coupled with 3 km ROMS, while a version of 3 km WRF coupled with 3 km ROMS is in a test mode. This study is a first step to evaluate the impact of high-resolution coupled model with dynamically downscaling CDA on the extended-range predictions, focusing on forecasts of typhoon onset, improved precipitation and typhoon intensity forecasts as well as simulation of the Kuroshio current variability associated with mesoscale oceanic activities. The results show that for realizing the extended-range predictability of atmospheric and oceanic environment characterized by statistics of mesoscale activities, a fine resolution coupled model resolving local mesoscale phenomena with balanced and coherent coupled initialization is a necessary first step. The next challenges include improving the planetary boundary physics and the representation of air-sea and air-land interactions to enable the model to resolve kilometer or sub-kilometer processes.

13.
Mar Genomics ; 52: 100722, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31677976

RESUMEN

Marine Bacteroidetes are well known for their functional specialization on the decomposition of polysaccharides which results from a great number of carbohydrate-active enzymes. Here we represent the complete genome of a Bacteroitedes member Echinicola rosea JL3085T that was isolated from surface seawater of the South China Sea. The genome is 6.06 Mbp in size with a GC content of 44.1% and comprises 4613 protein coding genes. A remarkable genomic feature is that the number of glycoside hydrolase genes in the genome of E. rosea JL3085T is high in comparison with most of the sequenced members of marine Bacteroitedes. E. rosea JL3085T genome harbored multi-gene polysaccharide utilization loci (PUL) systems involved in the degradation of pectin, xylan and arabinogalactan. The large diversity of hydrolytic enzymes supports the use of E. rosea JL3085T as a candidate for biotechnological applications in enzymatic conversion of plant polysaccharides.


Asunto(s)
Bacteroidetes/genética , Genoma Bacteriano , Bacteroidetes/metabolismo , Océano Pacífico , Pectinas/metabolismo , Agua de Mar/microbiología , Secuenciación Completa del Genoma , Xilanos/metabolismo
14.
Science ; 363(6430)2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30819937

RESUMEN

The El Niño-Southern Oscillation (ENSO), which originates in the Pacific, is the strongest and most well-known mode of tropical climate variability. Its reach is global, and it can force climate variations of the tropical Atlantic and Indian Oceans by perturbing the global atmospheric circulation. Less appreciated is how the tropical Atlantic and Indian Oceans affect the Pacific. Especially noteworthy is the multidecadal Atlantic warming that began in the late 1990s, because recent research suggests that it has influenced Indo-Pacific climate, the character of the ENSO cycle, and the hiatus in global surface warming. Discovery of these pantropical interactions provides a pathway forward for improving predictions of climate variability in the current climate and for refining projections of future climate under different anthropogenic forcing scenarios.

15.
Artículo en Inglés | MEDLINE | ID: mdl-30533702

RESUMEN

Pelagicola sp. strain LXJ1103, a representative of a new species in the family Rhodobacteraceae, was isolated from the coastal surface waters in Xiamen, China. Here, we announce the draft genome sequence and initial findings from a preliminary analysis of strain LXJ1103.

16.
Artículo en Inglés | MEDLINE | ID: mdl-30533704

RESUMEN

Phaeobacter sp. strain JL2872 was isolated from surface waters in the South China Sea. We report here the draft genome sequence of strain JL2872, which can contribute to our understanding of the characteristics of the members of the genus Phaeobacter.

17.
Nat Commun ; 9(1): 2398, 2018 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-29904159

RESUMEN

The original version of this Article omitted the author N. Penny Holliday from the National Oceanography Centre, European Way, Southampton SO14 3ZH, UK. Consequently, the following was originally omitted from the Acknowledgements: 'N.P.H. and the JR302 cruise were funded through the UK Natural Environment Research Council programmes UK OSNAP (NE/K010875/1), RAGNARRoCC (NE/K002511/1) and the Extended Ellett Line (National Capability)'. The corrected version of the Acknowledgements also removes the following from the original version: 'The Zonally Accumulated Heat Transport in observation was calculated by N.P.H. from the National Ocean Center, United Kingdom'.Additionally, the following was originally omitted from the Author Contributions: 'N.P.H. calculated the observed Zonally Accumulated Heat Transport along the OSNAP east section'.This has been corrected in both the PDF and HTML versions of the Article.

18.
Nat Commun ; 9(1): 1419, 2018 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-29650992

RESUMEN

Extreme positive Indian Ocean Dipole (pIOD) affects weather, agriculture, ecosystems, and public health worldwide, particularly when exacerbated by an extreme El Niño. The Paris Agreement aims to limit warming below 2 °C and ideally below 1.5 °C in global mean temperature (GMT), but how extreme pIOD will respond to this target is unclear. Here we show that the frequency increases linearly as the warming proceeds, and doubles at 1.5 °C warming from the pre-industrial level (statistically significant above the 90% confidence level), underscored by a strong intermodel agreement with 11 out of 13 models producing an increase. However, in sharp contrast to a continuous increase in extreme El Niño frequency long after GMT stabilisation, the extreme pIOD frequency peaks as the GMT stabilises. The contrasting response corresponds to a 50% reduction in frequency of an extreme El Niño preceded by an extreme pIOD from that projected under a business-as-usual scenario.

19.
Nat Commun ; 9(1): 1124, 2018 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-29555904

RESUMEN

The ocean's role in global climate change largely depends on its heat transport. Therefore, understanding the oceanic meridional heat transport (MHT) variability is a fundamental issue. Prevailing observational and modeling evidence suggests that MHT variability is primarily determined by the large-scale ocean circulation. Here, using new in situ observations in the eastern subpolar North Atlantic Ocean and an eddy-resolving numerical model, we show that energetic mesoscale eddies with horizontal scales of about 10-100 km profoundly modulate MHT variability on time scales from intra-seasonal to interannual. Our results reveal that the velocity changes due to mesoscale processes produce substantial variability for the MHT regionally (within sub-basins) and the subpolar North Atlantic as a whole. The findings have important implications for understanding the mechanisms for poleward heat transport variability in the subpolar North Atlantic Ocean, a key region for heat and carbon sequestration, ice-ocean interaction, and biological productivity.

20.
Genome Announc ; 5(34)2017 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-28839015

RESUMEN

Type strain JLT2012 was isolated from the southeastern Pacific. Here, we report the draft genome sequence and the initial findings from a preliminary analysis of strain JLT2012, which represents a novel species and should be classified in the existing genus Pacificimonas.

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