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This study used the Community Atmospheric Model 3.5 (CAM3.5) to investigate the effects of carbonaceous aerosols on climate. The simulations include control runs with 3 times the mass of carbonaceous aerosols as compared to the model's default carbonaceous aerosol mass, as well as no-carbon runs in which carbonaceous aerosols were removed. The slab ocean model (SOM) and the fixed sea surface temperature (SST) were used to examine effects of ocean boundary conditions. Throughout this study, climate response induced by aerosol forcing was mainly analyzed in the following three terms: (1) aerosol radiative effects under fixed SST, (2) effects of aerosol-induced SST feedbacks, and (3) total effects including effects of aerosol forcing and SST feedbacks. The change of SST induced by aerosols has large impacts on distribution of climate response; the magnitudes in response patterns such as temperature, precipitation, zonal winds, mean meridional circulation, radiative fluxes, and cloud coverage are different between the SOM and fixed SST runs. Moreover, different spatial responses between the SOM and fixed SST runs can also be seen in some local areas. This implies the importance of SST feedbacks on simulated climate response. The aerosol dimming effects cause a cooling predicted at low layers near the surface in most carbonaceous aerosol source regions. The temperature response shows a warming (cooling) predicted in the north (south) high latitudes, suggesting that aerosol forcing can cause climate change in regions far away from its origins. Our simulation results show that direct and semidirect radiative forcing due to carbonaceous aerosols decreases rainfall in the tropics. This implies that carbonaceous aerosols have possibly strong influence on weakening of the tropical circulation. Most changes in precipitation are negatively correlated with changes of radiative fluxes at the top of model. The changes in radiative fluxes at top of model are physically consistent with the response patterns in cloud fields. On global average, low-level cloud coverage increases, and mid- and high-level cloud coverage decreases in response to changes in radiative energy induced by aerosol forcing. An approximated moisture budget equation was analyzed in order to understand physical mechanism of precipitation changes induced by carbonaceous aerosols. Our results show that changes in tropical precipitation are mainly dominated are mainly dominated by the dynamic effect (i.e., vertical moisture transport carried by the perturbed flow). © Author(s) 2013.

Two series of samples of single-layer IrMn and IrMn/FePd bilayer films, deposited on a single-crystal MgO substrate at different IrMn deposition temperatures (Ts=300-700 °C), were investigated using magnetron sputtering. L12 ordering was revealed for the 30nm-thick IrMn epitaxial (001) films with Ts⩾400 °C, determined by synchrotron radiation x-ray diffractometry (XRD). XRD results also provide evidence of the epitaxial growth of the IrMn films on MgO substrate. Increasing Ts from 400 to 700 °C monotonically increases the ordering parameter of L12 phases from 0.17 to 0.81. An in-plane exchange bias field (Heb) of 22Oe is obtained in a 10nm-thick FePd film that is deposited on the disordered IrMn films. As the L12 ordering of the IrMn layers increases, the Heb gradually decreases to 0Oe, meaning that the exchange bias behavior vanishes. The increased surface roughness, revealed by atomic force microscopy, of the epitaxial IrMn layers with increasing Ts cannot be the main cause of the decrease in Heb due to the compensated surface spins regardless of the disordered and ordered (001) IrMn layers. The change of antiferromagnetic structure from the A1 to the L1H2 phase was correlated with the evolution of Heb. [ABSTRACT FROM AUTHOR]

Introduction: Amidst the widespread proliferation of the COVID-19 virus, brain fog has become one of the most critical issues of public health. Brain fog may lead to sub-health conditions, such as forgetfulness, difficulty thinking, and other related symptoms. Although they are not immediately life-threatening, these sub-health conditions could gradually erode the quality of life. Currently, there is no relevant screening tool for brain fog. Objectives: The aim of this study was to develop a reliable screening tool. Methods: A web-based brain fog screening questionnaire was developed in the study. It was based on previous studies, which summarized five parts of the most common clinical symptoms after COVID-19: forgetfulness, difficulty thinking, difficulty concentrating, feeling confused, and difficulty finding words or phrases to speak. Unfortunately, these items were used only in a way of yes or no answers in previous studies. Each of these items was expanded to five anchors to evaluate their severity in the study. Cronbach's alpha coefficient was used to assess internal consistency. K-means clustering was used as a second method to validate the cutoff points. Furthermore, the receiver operating characteristic (ROC) curve was applied to validate the appropriateness of the cutoff point. Results: There were 534 participants who completely finished the questionnaire. It includes 183 males and 351 females, and all of them aged between 19 and 81 years. The Cronbach's Alpha value was 0.821. The cutoff point was at a total score of 6 in terms of K-means. Based on the result, the ROC curve revealed that an area under the curve (AUC) was 0.816 with a confidence interval of 0.784 to 0.849. Conclusions: The study demonstrated the feasibility and reliability of the web-based screening test for brain fog. Disclosure of Interest: None Declared [ABSTRACT FROM AUTHOR]

OBJECTIVE: Acute type A aortic dissection (ATAAD) is a severe, rapidly progressing disease which typically requires patients to undergo emergency surgical intervention. Despite advancements in surgical procedures, still, ATAAD remains a surgical emergency associated with high mortality. The aim of this systematic review and meta-analysis was to compare whether either ascending aorta replacement (AR) or total aortic arch replacement (TR) leads to improved short- and long-term clinical outcomes. MATERIALS AND METHODS: A search of PubMed, Embase, Science Direct, Web of Science, SciELO, BIOSIS, and China National Knowledge Infrastructure (CNKI) databases were supplemented by searching through bibliographies of key articles. Thereafter, data on early and late prognostic factors were extracted. A systematic review and meta-analysis of 15 studies were performed to compare whether either AR or TR leads to a reduction in the risk of in-hospital and short-term mortality, postoperative complications, re-operation rate, and longterm mortality. RESULTS: A total of 15 cohort studies (n = 2822 patients with ATAAD; AR with HA, partial arch = 1911, TR = 911) were deemed eligible and included in the meta-analysis. Compared with TR, AR led to a significantly lower risk of in-hospital mortality (RR = 0.77; 95% CI: 0.61-0.96), shorter cardiopulmonary bypass time (CPB, mean difference = -53.09; 95% CI: -56.68–-49.50), circulatory arrest time (CA, mean difference = -8.09; 95% CI: -9.04-7.15), and antegrade cerebral perfusion (ACP, mean difference = -28.62; 95% CI: -30.23–-27.00). Differences in the incidence rates of neurological dysfunctions and renal dialysis were not significant. The pooled rate of aortic re-operation was lower in TR group (AR 7.6% vs. TR 5.3%), albeit not significantly (risk ratio = 1.39; 95% CI: 0.94-2.07; p = 0.10). CONCLUSIONS: These findings demonstrate that AR is associated with a lower early mortality rate and shorter operative times overall. Nevertheless, the incidence of postoperative complications in patients undergoing AR is comparable to that of patients undergoing TR. Further prospective follow-up data needs to be collected and analyzed to discern whether there are statistically significant differences in the risks of re-operation and long-term mortality between AR and TR procedures. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Current cardiac risk assessments such as EuroSCORE II and the STS-Score do not take liver dysfunction into account. The purpose of this study was to evaluate the prevalence and post-operative morbidity risk factors following cardiac surgery of patients with chronic viral hepatitis. PATIENTS AND METHODS: The study group consisted of 105 patients with documented chronic viral hepatitis who were subject to elective cardiac surgery from 2001 to 2012. Subjects were evaluated for pre-operative liver dysfunction according to the MELD score. RESULTS: The average MELD score of the study group was 10.00 ± 6.00. The average EuroSCORE ii of the study group was 2.07% ± 1.62%. The primary post-operative complication was cardiac complications (n=57, 54.3%). Analysis showed significant differences in meld score, bilirubin and smoking. Multivariate logistic regression analysis showed that the variables entering into the model included such risk factors with a significant or near significant (p < 0.2) influence on hospital morbidity and consisted in valve vs. coronary artery disease, valve/cad, aortic valve replacement vs. Coronary artery bypass graft, and bilirubin (mg/dl). CONCLUSIONS: it is vital that liver dysfunction is added to the risk models which are currently utilized to predict the post-operative morbidity of cardiac surgery patients. [ABSTRACT FROM AUTHOR]