The calculation of the consolidation settlement of clayey soils with creep behaviour has been a challenging issue with a long history. After a brief review the assumptions made in the two methods based on Hypothesis A and Hypothesis B, the authors present a new simplified hypothesis B method for calculation of consolidation settlement of a clayey soil with creep. Equations of this method are derived based on the “equivalent time” concept for different stress–strain states. This simplified Hypothesis B method is then used to calculate the consolidation settlement of a number of typical consolidation problems. The approximation and verification of this simplified method are examined by comparing the calculated settlements with settlements computed using two fully coupled finite element (FE) consolidation analysis programs using elastic viscoplastic (EVP) constitutive models (Hypothesis B) and the Hypothesis A method. It is found that the curves calculated using the new Hypothesis B simplified method with a factor α = 0.8 are close to curves from two FE model simulations with relative errors in the range 0.37%∼8.42% only for three layers of Hong Kong marine clay (HKMC). In overall, the settlements calculated using Hypothesis A method are smaller than those from the two FE simulations with relative error in the range 6.52%∼46.17% for the three layers of HKMC. In addition, this new simplified Hypothesis B method is used to calculate the average strain of consolidation tests done by Berre and Iversen in 1972. The calculated results are compared with the test data, and values from a fully coupled finite difference (FD) consolidation analysis using Yin and Graham’s EVP constitutive model (Hypothesis B), and Hypothesis A method. It is found that, again, the results from the new simplified Hypothesis B method are very close to the measured data. In conclusion, the new simplified Hypothesis B method is a suitable simple method, by spread-sheet calculation of the consolidation settlement of a single layer of a clayey soil with creep.
BackgroundThe Sustainable Development Goals (SDGs), adopted by all United Nations (UN) member states in 2015, established a set of bold and ambitious health-related targets to achieve by 2030. Understanding China’s progress toward these targets is critical to improving population health for its 1.4 billion people.Methods and findingsWe used estimates from the Global Burden of Disease (GBD) Study 2016, national surveys and surveillance data from China, and qualitative data. Twenty-eight of the 37 indicators included in the GBD Study 2016 were analyzed. We developed an attainment index of health-related SDGs, a scale of 0–100 based on the values of indicators. The projection model is adjusted based on the one developed by the GBD Study 2016 SDG collaborators.We found that China has achieved several health-related SDG targets, including decreasing neonatal and under-5 mortality rates and the maternal mortality ratios and reducing wasting and stunting for children. However, China may only achieve 12 out of the 28 health-related SDG targets by 2030. The number of target indicators achieved varies among provinces and municipalities. In 2016, among the seven measured health domains, China performed best in child nutrition and maternal and child health and reproductive health, with the attainment index scores of 93.0 and 91.8, respectively, followed by noncommunicable diseases (NCDs) (69.4), road injuries (63.6), infectious diseases (63.0), environmental health (62.9), and universal health coverage (UHC) (54.4). There are daunting challenges to achieve the targets for child overweight, infectious diseases, NCD risk factors, and environmental exposure factors. China will also have a formidable challenge in achieving UHC, particularly in ensuring access to essential healthcare for all and providing adequate financial protection. The attainment index of child nutrition is projected to drop to 80.5 by 2025 because of worsening child overweight. The index of NCD risk factors is projected to drop to 38.8 by 2025. Regional disparities are substantial, with eastern provinces generally performing better than central and western provinces. Sex disparities are clear, with men at higher risk of excess mortality than women. The primary limitations of this study are the limited data availability and quality for several indicators and the adoption of "business-as-usual" projection methods.ConclusionThe study found that China has made good progress in improving population health, but challenges lie ahead. China has substantially improved the health of children and women and will continue to make good progress, although geographic disparities remain a great challenge. Meanwhile, China faced challenges in NCDs, mental health, and some infectious diseases. Poor control of health risk factors and worsening environmental threats have posed difficulties in further health improvement. Meanwhile, an inefficient health system is a barrier to tackling these challenges among such a rapidly aging population. The eastern provinces are predicted to pe...
Aims This study aims to analyse whether inhaled nitric oxide (iNO) was beneficial in the treatment of coronavirus disease 2019 (COVID‐19) patients with pulmonary hypertension. Methods and results Five critically ill COVID‐19 patients with pulmonary hypertension designated Cases 1–5 were retrospectively included. Clinical data before and after iNO treatment were serially collected and compared between patients with or without iNO treatment. The five cases experienced pulmonary artery systolic pressure (PASP) elevation (≥50 mmHg) at 30, 24, 33, 23, and 24 days after illness onset (d.a.o), respectively. Cases 1–3 received iNO treatment on the 24th, 13th, and 1st day after the first elevation of PASP, with concentrations varied from 10 to 20 ppm based on the changes of PASP and blood pressure for 10, 9, and 5 days, respectively. Upon iNO treatment, PASP of Cases 1 and 2 returned to normal on the 10th day and 1st day, and maintained between 50 and 58 mmHg in Case 3. Pa0 2 /Fi0 2 increased from 88 to 124, 51 to 118, and 146 to 244, respectively. SPO 2 increased from 91% to 97% for Case 1 and maintained a high level above 97% for Case 2. Cardiac function remained normal in the three patients after treatment. Moreover, Cases 1 and 3 survived from severe acute respiratory syndrome coronavirus 2 infection, while Case 2 finally died on the 36th day after the first elevation of PASP due to severe complications. Both cases who did not receive iNO treatment experienced a sudden decrease of PASP and Pa0 2 /Fi0 2 due to right heart failure and then died. Conclusions Inhaled nitric oxide treatment was beneficial in reducing and stabilizing the PASP and might also reduce the risk of right heart failure in COVID‐19 with pulmonary hypertension.
SCOVID-19 originated in Wuhan and rippled across China. We investigate how the geographical distance of working adults to the epicenter of Wuhan predicts their burnout. Preliminary results of a survey of 308 working adults in 53 cities showed working adults' distance to the epicenter of Wuhan had an inverted U-shaped relationship with their burnout. Such results help to identify regions where people would need more psychiatric assistance, carrying direct implications to healthcare practitioners and policymakers.
PurposeBridge to elective surgery (BTS) using self-expanding metal stents (SEMS) is a common alternative to emergency surgery (ES) for acute malignant left-sided colonic obstruction (AMLCO). However, the study regarding long-term impact of BTS is limited and unclear.MethodsA multicenter observational study was performed at three hospitals from April 2012 to December 2019. Propensity score matching (PSM) was introduced to minimize selection bias. The primary endpoint was overall survival. The secondary endpoints included surgical approaches, primary resection types, total stent related adverse effects (AEs), surgical AEs, length of hospital stay, 30-day mortality and tumor recurrence.Results49 patients in both BTS and ES group were matched. Patients in the BTS group more often underwent laparoscopic resection (31 [63.3%] vs 8 [16.3%], p<0.001), less likely to have a primary stoma (13 [26.5%] vs 26 [53.1%], p=0.007) and more often had perineural invasion (25 [51.0%] vs 13 [26.5%], p=0.013). The median overall survival was significantly lower in patients with stent insertion (41 vs 65 months, p=0.041). 3-year overall survival (53.0% vs 77.2%, p=0.039) and 5-year overall survival (30.6% vs 55.0%, p=0.025) were significantly less favorable in the BTS group. In the multivariate Cox regression analysis, stenting (hazard ratio(HR)= 2.309(1.052-5.066), p=0.037), surgical AEs (HR=1.394(1.053-1.845), p=0.020) and pTNM stage (HR=1.706(1.116-2.607), p=0.014) were positively correlated with overall survival in matched patients. ConclusionsSelf-expanding metal stents as “a bridge to surgery” is associated with more perineural invasion, higher recurrence rate and worse overall survival in patients with acute malignant left-sided colonic obstruction compared with emergency surgery.
In most marine reclamation projects, sand fills are directly placed on soft marine soils in the seabed. The sand particles can easily penetrate into the soft marine soils, and soft soils can also move into the pores inside sand through the initial contact interface between the sand and the soft soils. In this case, the permeability and the volume of the sand above the initial surface are reduced. To avoid this problem, a geotextile separator may be placed on the surface of the soft soils in the seabed before placing the sand. In this study, a two-dimensional (2-D) physical model is utilized to study the geotextile separator effects. The initial conditions of clayey soil, filled sand, and surcharge loading were kept the same in the physical model test with the only difference in that a geotextile separator was placed on the clay surface or not. The settlements of the initial interface were recorded and compared for the two cases without or with the geotextile separator. Particle size distributions of soils taken across the interface for different time durations were also measured, analyzed, and compared. Based on the result analysis, the sand percolation depth was 40 mm and fine particle suffusion was apparent when sand was directly placed on the marine slurry surface without using the geotextile separator. Comparatively, the sand percolation was avoided, and the fine particle suffusion was effectively diminished when the geotextile separator was utilized. A relative fine particle fraction is defined to illustrate the immigrated fine particles from clay to sand soils. The fine particle percentages of the HKMD-sand mixtures are calculated for the two cases without and with a geotextile separator for a better analysis of the geotextile separator effects in practice.
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