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By participating in the construction of China's Guangdong-Hong Kong-Macao Greater Bay Area (GBA) and as the core zone of the GBA, the region (PRD) aims to have the ambient air quality basically reaching the level of the world-class bay areas by 2035. In this study, we developed three scenario strategies (Moderate Scenario (S_M), Intensified Scenario (S_I) and Radical Scenario (S_R)) for the PRD in 2035 taking the average annual PM_(2.5) concentrations in the PRD reaching the world health organization interim target 3 (WHO-III, 15 μg/m³) as the constraint standard. Under each scenario, we formulated the structural adjustment and end-of-pipe control measures to predict the development of industry, transportation and energy in the PRD in 2035. The results show that the total emissions of SO₂, NOx, PM (Particulate Matters) and NMVOCs (Non-methane Volatile Organic Compounds) were 152, 511, 205 and 382kt in the S_M scenario, respectively, and were 114, 436, 177 and 325kt in the S_I scenario, respectively, while they are 77, 344, 143 and 269kt in the S_R scenario, respectively. We also consider the emission reduction of pollutants outside the PRD. In this study, the S_M, S_I and S_R scenarios were combined with different national scenario inventories (DPEC) in 2035 and the WRF-CMAQ model was used to simulate these scenarios. The simulation results show that annual average concentrations of PM_(2.5) in the PRD under the S_M-DPEC1, S_I-DPEC2 and S_R-DPEC3 scenarios were expected to reach 15.1, 14.6 and 14.8 μg/m³, respectively, which just meet the WHO-III standard. In the process of achieving WHO-III target in the future, the government and policy makers can match the most suitable scenario in the study by referring to the actual decline of air pollutant emissions in the main contributing regions outside the PRD under each scenario, so as to obtain the best feasible control strategy in the PRD.

Supplemental Digital Content is available in the text, Background: It was under debate whether cryptogenic stroke patients benefited from patent foramen ovale (PFO) closure. We sought to determine secondary prevention strategy in these patients. Methods: Scientific databases were searched for randomized controlled trials enrolling cryptogenic stroke patients with PFO who underwent PFO closure or medical therapy. The random-effect model was used to analyze the outcomes. Results: We identified 6 trials enrolling 3630 participants in this meta-analysis. When compared with medical therapy, PFO closure reduced risks of recurrent stroke (risk ratio [RR] 0.52, 95% confidence interval [CI] 0.29–0.93) and composite of stroke and transient ischemic attack (TIA) (RR 0.60, 95% CI 0.46–0.80). And no differences in all-cause death (RR 0.80, 95% CI 0.37–1.72) and cardiovascular death (RR 1.47, 95% CI 0.36–5.94) between 2 groups were observed. The risks of major bleeding (RR 0.96, 95% CI 0.47–1.96) and any serious adverse event (RR 1.03, 95% CI 0.92–1.16) did not differ between 2 groups. Yet, PFO closure increased risk of atrial fibrillation (RR 4.25, 95% CI 2.10–8.60). Conclusion: PFO closure, as compared with medical therapy, was associated with decreased risk of recurrent stroke and increased risk of atrial fibrillation in cryptogenic stroke patients with PFO.

Distributed KEY-VALUE storage system is a new storage framework for cloud computing. It can enable an application to dynamically adapt to growing workloads by increasing the number of servers. However, current distributed KEY-VALUE storage systems are still inefficient on range query for larger result set. When the result set become large, the file layout, cache hit rate are both key points for IO efficiency. In this paper, we will introduce our experience under the development of China Mobile Big Cloud KEY-VLAUE DB (BC-kvDB). We will discuss how we increase IO efficiency in BC-kvDB. BC-kvDB is based on single-table space data model and provides SQL-LIKE DDL and DML language. BC-kvDB's high throughput is benefit from data locality storage, column-storage structure and multi-layer caches. Data can be accessed in local cache or local blocks through block index. Experimental results show that the random writing performance of BC-kvDB is 2.5 times better than HBase and the random reading performance is 1.8-2 times than HBase.

IDDRG - Conference Proceedings - Tools and Technologies for the Processing of ultra high strength steels