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Background: There is a growing concern that the use of anti-hypertensives may be associated with an increased risk of cancer, but it remains uncertain for the association between anti-hypertensives and lung cancer risk, as well as their interaction with aspirin in chemoprotective effects.Methods: The goal of this study is to assess the association between anti-hypertensives use and the risk of lung cancer, as well as the chemopreventive impacts from the combination usage of aspirin and anti-hypertensives. A retrospective cohort study was conducted based on all the public hospital electronic medical records in Hong Kong. Patients with prescription records of anti-hypertensives (ACEi/ARB, CCB, β-blocker,α-blocker) and/or aspirin were included as the exposure groups. Using the Cox proportional hazards model with inverse probability weighting, we estimated hazard ratios (HRs) with 95% confidence intervals (CIs) for lung cancer risk from anti-hypertensives usage or combination usage of aspirin with anti-hypertensives. The likelihood ratio test and interaction model were adopted for exploring the interaction effects with aspirin.Results: A total of 6592 and 84,116 lung cancer cases were identified from the groups of anti-hypertensives users and anti-hypertensives users with aspirin, respectively. The group of non-aspirin patients who received anti-hypertensives showed a significantly lower risk of lung cancer (HR: 0.63, 95% CI: 0.60-0.66), compared to those without anti-hypertensives. When aspirin and α-blocker were used simultaneously, it could lower the risk of lung cancer significantly (HR: 0.53, 95% CI: 0.34-0.84). Moreover, the lower risk of lung cancer persisted with a longer follow-up period of anti-hypertensives usage. Combination usage with aspirin in the users of ACEi/ARB, CCB, and α-blocker showed significant interaction effects. However, the smoking effect could not be eliminated in this analysis.Discussion: Anti-hypertensive treatment was associated with a lower risk of lung cancer, which is associated with the anti-hypertensives exposure period. The potential interaction on the chemopreventive influence from combination usage of α-blocker and aspirin might exist. More corroborations on these findings are needed to focus on the different settings in future studies. [ABSTRACT FROM AUTHOR]

Numerous studies have indicated that ambient particulate matter is closely associated with increased risk of cardiovascular disease, yet the evidence for its association with renal disease remains underrecognized. We aimed to estimate the association between long-term exposure to fine particulate matter, defined as particulate matter with an aerodynamic diameter less than or equal to 2.5 μm (PM2.5), and mortality from renal failure (RF) among participants in the Elderly Health Service Cohort in Hong Kong, China, from 1998 to 2010. PM2.5 concentration at the residential address of each participant was estimated based on a satellite-based spatiotemporal model. We used Cox proportional hazards regression to estimate risks of overall RF and cause-specific mortality associated with PM2.5. After excluding 5,373 subjects without information on residential address or relevant covariates, we included 61,447 participants in data analyses. We identified 443 RF deaths during the 10 years of follow-up. For an interquartile-range increase in PM2.5 concentration (3.22 μg/m3), hazard ratios for RF mortality were 1.23 (95% confidence interval: 1.06, 1.43) among all cohort participants and 1.42 (95% confidence interval: 1.16, 1.74) among patients with chronic kidney disease. Long-term exposure to atmospheric PM2.5 might be an important risk factor for RF mortality in the elderly, especially among persons with existing renal diseases. [ABSTRACT FROM AUTHOR]

The design of geotechnical structures depends significantly on soil stratigraphy. The determination of geological stratigraphy is generally based on site investigations such as drilling, standard penetration tests and cone penetration tests. When the in-situ tests or boreholes are limited, the characterization of complex strata is difficult. The objective of this study is to develop an improved coupled Markov chain model (CMC) to simulate complex geological stratigraphy based only on limited in-situ data. The traditional CMC model is improved by developing a direction-dependent CMC method to address the strong variation of soil properties among boreholes. The difficulty in simulating different dip directions and prisms in a geological profile is solved by developing proper simulation direction in the modelling. The stratigraphy at a construction site in Hong Kong is characterized using the proposed method. It is found that both upwards and downwards inclined interfaces can be simulated very well. The prisms within a soil layer can be predicted. The accuracy of the method is closely related to the locations of the existing boreholes. The influence distance of a borehole is approximately 14 m. [ABSTRACT FROM AUTHOR]

The large cylinder structures as the retaining structure for artificial islands, are crucial in mega sea-crossing infrastructure projects (such as the Hong Kong-Zhuhai-Macao Bridge project). As the structure is mainly embedded in sand or rock with a small embedment depth previously, the stability of large cylinder structures deeply embedded in soft clay remains unclear. Thus, this study explores the failure mode and ultimate load of such structure in thick, soft clays through experimentation and examines the effect of the sand compaction piles used to reinforce the soft clay. The results demonstrate that the sliding failure mode controls the stability of the large cylinder structure in soft clay and the slip surface consists of three parts in the soil: the active zone, the structure zone, and the passive zone. Moreover, the sand compaction piles can effectively raise the ultimate load of the structure when its replacement area ratio reaches 30%. The ultimate load of the structure also enlarges with increasing the embedment depth of the sand compaction piles. This study sheds light on the design of large cylinders as a retaining structure for artificial island. [ABSTRACT FROM AUTHOR]

A case study on the stability of the large cylindrical structures of Hong Kong-Zhuhai-Macao bridge is presented. In order to protect the sea environment and facilitate the sustainable development, a construction method of large cylindrical structures without dredging the intact marine clay was adopted for the first time. The stone column improvement method was used to strengthen the soft seabed soils in this project. However, the large cylindrical structures developed horizontal displacement up to 3–7 m which aroused suspicion of the safety of the artificial island in public. A three-dimensional finite-element method was developed to simulate the construction process of the structures step by step to seek consistency with the prototype. Results show that the horizontal displacement of the large cylindrical structures is 4 m under the design load. The obtained horizontal displacement agrees well with the field measurement. It is found that the earth pressure acting on the structures is a bit different with the Rankin's earth pressure. The load–horizontal displacement curve and earth pressure distribution were obtained considering the stone columns improvement method, which was further compared with the case without any improvement and the sand filling improvement method. The horizontal displacement with stone column improvement under the design load is 4 m, which is a bit smaller than that without any improvement (i.e., 4.8 m). More efficient improvement methods to strengthen the soft marine clay should be explored in the future. [ABSTRACT FROM AUTHOR]

Emerging epidemiologic studies suggested that particulate matter (PM) was a risk factor for the incidence of chronic kidney disease (CKD). However, few studies were conducted to examine whether PM was associated with cause-specific deaths in the CKD progression. This study aimed to estimate the association between fine particulate matter (PM 2.5) and a spectrum of deaths among CKD patients. We took leverage of the Elderly Health Service cohort (n = 66,820), a large Hong Kong elderly cohort followed up till 2010. A total of 902 CKD incident patients in the cohort were identified during the follow-up period. We estimated yearly PM 2.5 at the residential address for each CKD patient based on a satellite-based spatiotemporal model. We used Cox proportional hazards models with attained age as the underlying timescale to assess the association between long-term exposure to PM 2.5 and cause-specific mortality among CKD patients. A total of 496 patients died during the follow-up, where 147 died from cardiovascular disease, 61 from respiratory disease and 154 from renal failure. The mortality hazard ratio (HR) per interquartile-range increase in PM 2.5 (4.0 μg/m3) was 1.97 (95% confidence interval (CI): 1.34 to 2.91) for ischemic heart disease (IHD) among CKD patients, and was 1.42 (95%CI: 1.05 to 1.93) for CKD among those patients concomitantly with hypertension. Associations were not of statistical significance between PM 2.5 and mortality hazard ratios of all-cause, stroke, and pneumonia among CKD patients. Our findings suggest that long-term exposure to PM 2.5 may contribute to the CKD progression into ischemic heart diseases. • Evidence is limited on cause-specific mortality HRs with PM 2.5 among CKD patients. • Long-term exposure to PM 2.5 may increase the mortality HR of IHD among CKD patients. • PM 2.5 was associated with renal failure mortality among patients with hypertension. • Associations with all-cause, stroke and pneumonia mortality were not significant. [ABSTRACT FROM AUTHOR]