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Revisiting Asian monsoon formation and change associated with Tibetan Plateau forcing: II. Change
Data analysis based on station observations reveals that many meteorological variables averaged over the Tibetan Plateau (TP) are closely correlated, and their trends during the past decades are well correlated with the rainfall trend of the Asian summer monsoon. However, such correlation does not necessarily imply causality. Further diagnosis confirms the existence of a weakening trend in TP thermal forcing, characterized by weakened surface sensible heat flux in spring and summer during the past decades. This weakening trend is associated with decreasing summer precipitation over northern South Asia and North China and increasing precipitation over northwestern China, South China, and Korea. An atmospheric general circulation model, the HadAM3, is employed to elucidate the causality between the weakening TP forcing and the change in the Asian summer monsoon rainfall. Results demonstrate that a weakening in surface sensible heating over the TP results in reduced summer precipitation in the plateau region and a reduction in the associated latent heat release in summer. These changes in turn result in the weakening of the near-surface cyclonic circulation surrounding the plateau and the subtropical anticyclone over the subtropical western North Pacific, similar to the results obtained from the idealized TP experiment in Part I of this study. The southerly that normally dominates East Asia, ranging from the South China Sea to North China, weakens, resulting in a weaker equilibrated Sverdrup balance between positive vorticity generation and latent heat release. Consequently, the convergence of water vapor transport is confined to South China, forming a unique anomaly pattern in monsoon rainfall, the so-called “south wet and north dry.” Because the weakening trend in TP thermal forcing is associated with global warming, the present results provide an effective means for assessing projections of regional climate over Asia in the context of global warming
Luteolin Pretreatment Ameliorates Myocardial Ischemia/Reperfusion Injury by lncRNA-JPX/miR-146b Axis
Background. In the present study, we aimed to find out whether luteolin (Lut) pretreatment could ameliorate myocardial ischemia/reperfusion (I/R) injury by regulating the lncRNA just proximal to XIST (JPX)/microRNA-146b (miR-146b) axis. Methods. We established the models in vitro (HL-1 cells) and in vivo (C57BL/6J mice) to certify the protection mechanism of Lut pretreatment on myocardial I/R injury. Dual luciferase reporter gene assay was utilized for validating that JPX could bind to miR-146b. JPX and miR-146b expression levels were determined by RT-qPCR. Western blot was utilized to examine apoptosis-related protein expression levels, including cleaved caspase-9, caspase-9, cleaved caspase-3, caspase-3, Bcl-2, Bax, and BAG-1. Apoptosis was analyzed by Annexin V-APC/7-AAD dualstaining, Hoechst 33342 staining, as well as flow cytometry. Animal echocardiography was used to measure cardiac function (ejection fraction (EF) and fractional shortening (FS) indicators). Results. miR-146b was demonstrated to bind and recognize the JPX sequence site by dual luciferase reporter gene assay. The expression level of miR-146b was corroborated to be enhanced by H/R using RT-qPCR (P<0.001 vs. Con). Moreover, JPX could reduce the expression of miR-146b, whereas inhibiting JPX could reverse the alteration (P<0.001 vs. H/R, respectively). Western blot analysis demonstrated that Lut pretreatment increased BAG-1 expression level and Bcl-2/Bax ratio, but diminished the ratio of cleaved caspase 9/caspase 9 and cleaved caspase 3/caspase 3 (P<0.001 vs. H/R, respectively). Moreover, the cell apoptosis change trend, measured by Annexin V-APC/7-AAD dualstaining, Hoechst 33342 staining, along with flow cytometry, was consistent with that of apoptosis-related proteins. Furthermore, pretreatment with Lut improved cardiac function (EF and FS) (P<0.001 vs. I/R, respectively), as indicated in animal echocardiography. Conclusion. Our results demonstrated that in vitro and in vivo, Lut pretreatment inhibited apoptosis via the JPX/miR-146b axis, ultimately improving myocardial I/R injury
Repeatability and agreement of AOCT-1000 M, RTVue XR and IOL master 500 in measuring corneal thickness mapping and axial length applying principle of optical coherence tomography
Abstract Purpose To evaluate the repeatability and agreement of Fourier-domain optical coherence tomography (AOCT-1000 M and RTVue XR) and partial coherence interferometry biometer (IOL Master 500) in measuring corneal thickness mapping and axial length respectively. Methods Corneal thickness was measured by AOCT-1000 M and RTVue XR. Axial lengths were measured by AOCT-1000 M and IOL Master 500. The repeatability and agreement of corneal thickness and axial length were calculated in two groups of devices. The intraclass correlation coefficient (ICC) was used to verify the repeatability of the device. The 95% confidence interval of the difference compared to the set cut-off value was used to verify the agreement between the two devices. Results A total of 60 subjects with 58 eyes were included. The central corneal thickness measured by AOCT-1000 M and RTVue XR were 504.46 ± 42.53 μm and 504.43 ± 42.89 μm respectively. The average difference between groups was 0.03 ± 4.58 μm, and the 95% confidence interval was (-1.17, 1.24), which was far less than the set threshold value of 15 μm (P < 0.001). Both RTVue XR and AOCT-1000 M had very good ICC values of central corneal thickness (0.998 and 0.994, respectively). The average axial lengths measured by AOCT-1000 M and IOL Master 500 were 24.28 ± 1.25 mm and 24.29 ± 1.26 mm respectively and the 95% confidence interval was (-0.02, 0.01), which was less than the set threshold value of 0.15 mm (P < 0.001). The ICC for both devices were 1.000. Conclusion Good repeatability and agreement were seen in measurements of central corneal thickness and axial length by AOCT-1000 M
Are medical record front page data suitable for risk adjustment in hospital performance measurement? Development and validation of a risk model of in-hospital mortality after acute myocardial infarction
Objectives To develop a model of in-hospital mortality using medical record front page (MRFP) data and assess its validity in case-mix standardisation by comparison with a model developed using the complete medical record data.Design A nationally representative retrospective study.Setting Representative hospitals in China, covering 161 hospitals in modelling cohort and 156 hospitals in validation cohort.Participants Representative patients admitted for acute myocardial infarction. 8370 patients in modelling cohort and 9704 patients in validation cohort.Primary outcome measures In-hospital mortality, which was defined explicitly as death that occurred during hospitalisation, and the hospital-level risk standardised mortality rate (RSMR).Results A total of 14 variables were included in the model predicting in-hospital mortality based on MRFP data, with the area under receiver operating characteristic curve of 0.78 among modelling cohort and 0.79 among validation cohort. The median of absolute difference between the hospital RSMR predicted by hierarchical generalised linear models established based on MRFP data and complete medical record data, which was built as ‘reference model’, was 0.08% (10th and 90th percentiles: −1.8% and 1.6%). In the regression model comparing the RSMR between two models, the slope and intercept of the regression equation is 0.90 and 0.007 in modelling cohort, while 0.85 and 0.010 in validation cohort, which indicated that the evaluation capability from two models were very similar.Conclusions The models based on MRFP data showed good discrimination and calibration capability, as well as similar risk prediction effect in comparison with the model based on complete medical record data, which proved that MRFP data could be suitable for risk adjustment in hospital performance measurement