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1.
Heliyon ; 9(12): e23064, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38076090

RESUMO

Heat waves are meteorological disasters that inflict damage on public health and societal systems over extensive areas. The frequency and intensity of heat waves are increasing in many regions worldwide. However, insufficient research has been conducted to reduce forecast errors for heat waves in terms of short-range predictions. In this study, observing system experiments were performed using the Weather Research and Forecasting model and a three-dimensional variational data assimilation (DA), and the effects of observations used for DA on forecast errors for meteorological variables (i.e., upper atmospheric geopotential height, upper temperature, upper wind, and near-surface 2-m temperature) associated with heat wave were analyzed. As the forecast time increased, the 200 and 500 hPa geopotential heights in East Asia and the 2-m temperatures around Korea, Japan, and eastern China tended to be underestimated. All observations used for DA reduced the forecast errors for the meteorological variables associated with heat wave. Upper atmospheric observations (i.e., Advanced Microwave Sounding Unit-A (AMSU-A), aircraft, atmospheric motion vector, and radiosonde) played a more significant role in reducing forecast errors than near-surface observations. Among the upper atmospheric observations, AMSU-A had the greatest impact on reducing underestimation in forecasts for 200 and 500 hPa geopotential heights and the second greatest impact on 2-m temperature. The contraction of Tibetan high area at 200 hPa and Northern Pacific high area at 500 hPa in the experiments without using specific observations, compared to the analysis from the experiment using all observations, caused the deflection of the upper winds clockwise through the geostrophic relationship. Radiosonde observations had the greatest impact on reducing forecast errors of 2-m temperatures. Therefore, upper atmospheric observations are important for reducing errors in heat wave simulations in East Asia. The results of this study could help in designing an optimal observing system that reduces heat wave forecast errors in East Asia.

2.
PLoS One ; 17(2): e0263925, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35180259

RESUMO

To investigate the impact of two CO2 observation datasets obtained from the Korean Peninsula on the surface CO2 flux estimation over Asia, the two datasets are assimilated into the CarbonTracker (CT) inverse modeling system and the estimated surface CO2 fluxes are analyzed. Anmyeon-do (AMY) and Gosan (GSN) sites in the Korean Peninsula have observed surface CO2 mole fraction since the late 1990s. To investigate the effect of assimilating the additional Korean observations on the surface CO2 flux estimation over Asia, two experiments are conducted. The reference experiment (CNTL) only assimilates observations provided by National Oceanic and Atmospheric Administration (NOAA), while the other experiment (EXP1) assimilates both NOAA observations and two Korean observation datasets. The results are analyzed for 9 years from 2003 to 2011 in Asia region because both AMY and GSN datasets exist almost completely for this period. The annual average of estimated biosphere CO2 flux of EXP1 shows more flux absorption in summer and less flux emission from fall to spring compared to CNTL, mainly on Eurasia Temperate and Eurasia Boreal regions. When comparing model results to independent CO2 concentration data from surface stations and aircraft, the root mean square error is smaller for EXP1 than CNTL. The EXP1 yields more reduction on uncertainty of estimated biosphere CO2 flux over Asia, and the observation impact of AMY, GSN sites on flux estimation is approximately 11%, which is greater than other observation sites around the world. Therefore, the two CO2 observation sets in the Korean Peninsula are useful in reducing uncertainties for regional as well as global scale CO2 flux estimation.


Assuntos
Dióxido de Carbono/química , Vento , Ásia , Modelos Teóricos
3.
J Adv Model Earth Syst ; 11(8): 2503-2522, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31762931

RESUMO

The Tibetan Plateau is regarded as the Earth's Third Pole, which is the source region of several major rivers that impact more 20% the world population. This high-altitude region is reported to have been undergoing much greater rate of weather changes under global warming, but the existing reanalysis products are inadequate for depicting the state of the atmosphere, particularly with regard to the amount of precipitation and its diurnal cycle. An ensemble Kalman filter (EnKF) data assimilation system based on the limited-area Weather Research and Forecasting (WRF) model was evaluated for use in developing a regional reanalysis over the Tibetan Plateau and the surrounding regions. A 3-month prototype reanalysis over the summer months (June-August) of 2015 using WRF-EnKF at a 30-km grid spacing to assimilate nonradiance observations from the Global Telecommunications System was developed and evaluated against independent sounding and satellite observations in comparison to the ERA-Interim and fifth European Centre for Medium-Range Weather Forecasts Reanalysis (ERA5) global reanalysis. Results showed that both the posterior analysis and the subsequent 6- to 12-hr WRF forecasts of the prototype regional reanalysis compared favorably with independent sounding observations, satellite-based precipitation versus those from ERA-Interim and ERA5 during the same period. In particular, the prototype regional reanalysis had clear advantages over the global reanalyses of ERA-Interim and ERA5 in the analysis accuracy of atmospheric humidity, as well as in the subsequent downscale-simulated precipitation intensity, spatial distribution, diurnal evolution, and extreme occurrence.

4.
J Microbiol Biotechnol ; 24(11): 1583-91, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25112318

RESUMO

Ultraviolet (UV) irradiation alters multiple molecular pathways in the skin, thereby inducing skin damage, including photoaging. In recent years, probiotics have gained interest due to their beneficial effects on skin health, such as inhibiting atopic dermatitis and improving skin immunity or inflammation. However, little is known about the effects of probiotics on UVBinduced photoaging. In this study, we evaluated the effect of Lactobacillus plantarum HY7714 against UVB-induced photoaging in human dermal fibroblasts and hairless mice. The results showed that L. plantarum HY7714 treatment effectively rescued UVB-reduced procollagen expression through the inhibition of UVB-induced matrix metalloproteinase (MMP)-1 expression in human dermal fibroblasts. Data from a western blot showed that L. plantarum HY7714 inhibited the phosphorylation of Jun N-terminal kinase, thereby suppressing the UVB-induced phosphorylation and expression of c-Jun. Oral administration of L. plantarum HY7714 clearly inhibited the number, depth, and area of wrinkles in hairless mouse skin. Histological data showed that L. plantarum HY7714 significantly inhibited UVB-induced epidermal thickness in mice. Western blot and zymography data also revealed that L. plantarum HY7714 effectively inhibited MMP-13 expression as well as MMP-2 and -9 activities in dermal tissue. Collectively, these results provide further insight regarding the skin biological actions of L. plantarum HY7714, a potential skin anti-photoaging agent.


Assuntos
Lactobacillus plantarum , Probióticos/administração & dosagem , Probióticos/farmacologia , Envelhecimento da Pele/efeitos dos fármacos , Raios Ultravioleta/efeitos adversos , Administração Oral , Animais , Linhagem Celular , Feminino , Humanos , Metaloproteinase 1 da Matriz/metabolismo , Camundongos , Camundongos Pelados , Pró-Colágeno/metabolismo , Envelhecimento da Pele/efeitos da radiação
5.
Korean J Intern Med ; 17(1): 19-23, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12014208

RESUMO

BACKGROUND: The quality of sexuality is significantly affected by physical changes following hematopoietic stem cell transplantation (HSCT) and the dissatisfied and/or dysfunctional sexuality may cause deterioration in the quality of life (QOL). METHODS: With two models of questionnaires, we interviewed thirty-eight patients who remained in the disease-free status after HSCT and had sex partners, to assess: 1) the changes in sexuality, 2) QOL in physical, psychological, social and spiritual domains and 3) the correlation between sexuality and QOL. RESULTS: The common physical changes that may affect sexuality in women were secondary amenorrhea (69.2%), loss of sexual interest (53.8%), diminished vaginal secretion (50%), menopausal syndrome (34.6%), dyspareunia (30.8%) and failure to orgasm (23.1%), while men complained of impotence (41.7%) and difficulty in ejaculation (16.7%). For sexuality, satisfaction of sexual activity, attainment of orgasm and frequency of intercourse decreased significantly after HSCT as compared with the pre-transplant levels. A score measuring, QOL after HSCT marked 5.91 on a full score of 10; social domain ranked the lowest (5.01) while physical domain the highest (6.70). Among the items of sexuality, only sexual desire was significantly correlated with QOL; satisfaction, orgasm and frequency were not significantly correlated with QOL. CONCLUSION: Although sexuality is affected by the physical changes following HSCT, we should not overlook the psychological and social effects on the sexuality of post-transplant patients. Therefore, educational and counseling programs are very important to restore and improve their sexuality.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Disfunções Sexuais Fisiológicas/etiologia , Sexualidade , Adulto , Feminino , Transplante de Células-Tronco Hematopoéticas/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Inquéritos e Questionários
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