Satellite-based estimate of the variability of warm cloud properties associated with aerosol and meteorological conditions

Aerosol-cloud interaction (ACI) is examined using 10 years of data from the MODIS/Terra (morning orbit) and MODIS/Aqua (afternoon orbit) satellites. Aerosol optical depth (AOD) and cloud properties retrieved from both sensors are used to explore in a statistical sense the morning-to-afternoon variation of cloud properties in conditions with low and high AOD, over both land and ocean. The results show that the interaction between aerosol particles and clouds is more complex and of greater uncertainty over land than over ocean. The variation in d(Cloud_X), defined as the mean change in cloud property Cloud_X between the morning and afternoon overpasses in high-AOD conditions minus that in low-AOD conditions, is different over land and ocean. This applies to cloud droplet effective radius (CDR), cloud fraction (CF) and cloud top pressure (CTP), but not to cloud optical thickness (COT) and cloud liquid water path (CWP). Both COT and CWP increase over land and ocean after the time step, irrespective of the AOD. However, the initial AOD conditions can affect the amplitude of variation of COT and CWP. The effects of initial cloud fraction and meteorological conditions on the change in CF under lowand high-AOD conditions after the 3 h time step over land are also explored. Two cases are considered: (1) when the cloud cover increases and (2) when the cloud cover decreases. For both cases, we find that almost all values of d(CF) are positive, indicating that the variations of CF are larger in high AOD than that in low AOD after the 3 h time step. The results also show that a large increase in cloud fraction occurs when scenes experience large AOD and stronger upward motion of air parcels. Furthermore, the increase rate of cloud cover is larger for high AOD with increasing relative humidity (RH) when RH is larger than 20 %. We also find that a smaller increase in cloud fraction occurs when scenes experience larger AOD and larger initial cloud cover. Overall, the analysis of the diurnal variation of cloud properties provides a better understanding of aerosol-cloud interaction over land and ocean.Peer reviewe

Assessing the Fire-Modified Meteorology of the Grassland and Forest Intersection Zone in Mongolia Using the WRF-Fire Model

Climate change is already significantly affecting the frequency of wildfires in most regions of the world, and the risk of wildfires is expected to amplify further with global warming. Accordingly, there is growing concern about the mechanisms and impacts of extreme fires. In this study, a coupling of the Weather Research and Forecasting model and the Rothermel Fire model (WRF-Fire) is employed to reproduce the spread of fire within the national boundary of inner Mongolia from 21 to 27 May 2009. Simulations were run with or without feedback from fire-to-atmosphere models, and the study focused on how the energy flux of simulated fires changes the local meteorological environment. The coupled simulation could reproduce the burned area well, and the wind speed was the dominant factor in the fire spread, with a maximum value no more than 6.4 m/s, when the terrain height changes little and the proportion of grassland is low. After the feedback, the propagation speed of the fire accelerated, accompanying the release of latent and sensible heat, and local circulation formed near the front of the fire, leading to a convergence and divergence zone in the downwind area. It is worth noting that during a period of more than 140 h of simulation, the area of the fire field increased by 17% from ignition time. Therefore, considering the fire–atmosphere interaction is necessary for accurately predicting fire behavior

Compositional effect on TCP phase formation in Ru-containing Ni-based single crystal superalloys

Microstructural instability involving the formation of topologically close-packed (TCP) phases is restricted during the alloy development of Ni-based single crystal superalloys. In this study, the effects of alloying elements including Co, Cr, Mo and Ru on the formation of different TCP phases were investigated in a series of single crystal superalloys. Experimental results showed that more additions of Cr and Mo promoted the TCP phase formation, while Co and Ru played a positive role in improving microstructural stability. It is indicated that σ, P and R phases existed with various morphology and compositions in different experimental alloys during thermal exposure at 1100 ∘C. The content of Co, Cr and Mo in those alloys affected the types of TCP phases significantly, while Ru additions showed a negligible effect. R phase was prone to form in alloys containing high level of Co addition. Meanwhile, the ratio of Cr and Mo content had strong influence on the formation of σ and P phases in alloys containing low level of Co addition. The effects of alloying additions on the elemental partitioning ratios between γ and γ′ phases contributed to their corresponding influence on TCP phase formation

miR-1929-3p Overexpression Alleviates Murine Cytomegalovirus-Induced Hypertensive Myocardial Remodeling by Suppressing Ednra/NLRP3 Inflammasome Activation

MicroRNAs (miRNAs) play crucial roles in the development of essential hypertension (EH). Previously, we found that the expression of miR-1929-3p was decreased in C57BL/6 mice with hypertension induced by murine cytomegalovirus (MCMV). In this study, we explored the role of miR-1929-3p in hypertension myocardial remodeling in MCMV-infected mice. First, we measured MCMV DNA and host IgG and IgM after infection and determined the expression of miR-1929-3p and its target gene endothelin A receptor (Ednra) mRNA in the myocardium of mice. Then, we performed invasive blood pressure (BP) monitoring. Heart-to-body weight ratio (HW/BW%), along with mRNA levels of B-type natriuretic peptide (BNP) and beta myosin heavy chain (β-MHC), revealed myocardial remodeling. Hematoxylin/eosin and Masson’s trichrome staining indicated morphological changes in the myocardium. Cardiac function was assessed via echocardiography. Moreover, MCMV-infected mice were injected with recombinant adeno-associated virus- (rAAV-) miR-1929-3p overexpression vector. Immunohistochemistry and western blotting showed the expression of Ednra and the activation of NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome. And enzyme-linked immunosorbent assay (ELISA) revealed the concentrations of endothelin-1 (ET-1), interleukin-1β (IL-1β), and interleukin-18 (IL-18). In this study, we found that decreased expression of miR-1929-3p in MCMV-infected mice induced high BP and further development of myocardial remodeling cardiac function injury through increased expression of Ednra. Strikingly, overexpression of miR-1929-3p ameliorated these pathological changes of the heart. The positive effect was shown to be associated with inhibition of NLRP3 inflammasome activation and decreased expression of key proinflammatory cytokine IL-1β. Collectively, these results indicate that miR-1929-3p overexpression may effectively alleviate EH myocardial remodeling by suppressing Ednra/NLRP3 inflammasome activation in MCMV-infected mice

Comparison of long-term radial artery occlusion via distal vs. conventional transradial access (CONDITION): a randomized controlled trial

Abstract Background The distal transradial access (dTRA) has become an attractive and alternative access to the conventional transradial access (TRA) for cardiovascular interventional diagnosis and/or treatment. There was a lack of randomized clinical trials to evaluate the effect of the dTRA on the long-term radial artery occlusion (RAO). Methods This was a prospective, randomized controlled study. The primary endpoint was the incidence of long-term RAO at 3 months after discharge. The secondary endpoints included the successful puncture rate, puncture time, and other access-related complications. Results The incidence of long-term RAO was 0.8% (3/361) for dTRA and 3.3% (12/365) for TRA (risk ratio = 0.25, 95% confidence interval = 0.07–0.88, P = 0.02). The incidence of RAO at 24 h was significantly lower in the dTRA group than in the TRA group (2.5% vs. 6.7%, P < 0.01). The puncture success rate (96.0% vs. 98.5%, P = 0.03) and single puncture attempt (70.9% vs. 83.9%, P < 0.01) were significantly lower in the dTRA group than in the TRA group. However, the number of puncture attempts and puncture time were higher in the dTRA group. The dTRA group had a lower incidence of bleeding than the TRA group (1.5% vs. 6.0%, P < 0.01). There was no difference in the success rate of the procedure, total fluoroscopy time, or incidence of other access-related complications between the two groups. In the per-protocol analysis, the incidence of mEASY type ≥ II haematoma was significantly lower in the dTRA group, which was consistent with that in the as-treated analysis. Conclusions The dTRA significantly reduced the incidence of long-term RAO, bleeding or haematoma. Trial registration ClinicalTrials.gov identifer: NCT05253820