Increased river flow enhances the resilience of spatially patterned mudflats to erosion.

Estuarine mudflats are profoundly affected by increased coastal erosion and reduced sediment delivery from major rivers. Although managers are having difficulties to control the cause of increased coastal erosion, they can help to manage the resilience of mudflat ecosystems to erosion through river flow regulation. In this study, we associated the resilience of a mudflat ecosystem to erosion with various magnitudes of river flow using a mechanism-based eco-morphodynamic model. Ecosystem resilience was reported in terms of i) what range of erosion rate the system can withstand before function collapse (persistence), ii) at which point function can be recovered (recovery), and iii) the uncertainty of system response to disturbances (response uncertainty). Specifically, the function of intertidal mudflat was characterized by landscape heterogeneity, primary productivity, and sediment stabilization. In a case study of the Yellow River Estuary (YRE) of China, it is found that increased erosion induced a collapse of the functioning state. Once collapsed, the erosion rate at which mudflat could recovered was lower than the erosion rate at which mudflat collapsed. Increased river flow enhanced the resilience of the mudflat ecosystem to erosion by increasing sediment deposition rate, which was an important attribute in the interaction process driving ecosystem resilience. Furthermore, given the same river flow allocation, the system with dynamic grazer population was more resilient than the system with a constant grazer number, highlighting the importance of controlling mudflat aquaculture to optimize the performance of river flow regulation. Our modeling results are dependent on the environment with several assumptions, however, as a preliminary, we believe our work represents a fundamental shift to modeling ecosystem resilience based on the mechanism of bio-physical interactions rather than relying on just quantifying the vital rates of particular species to compare river flow scenarios.

The dose-response relationship between BMI and hypertension based on restricted cubic spline functions in children and adolescents: A cross-sectional study.

Background: A high body mass index (BMI) is a major risk factor for hypertension. The purpose of this study was to investigate the association between the BMI and hypertension in children and adolescents. Methods: We analyzed physical examination data from 29,810 students aged 6-14 years old. A restricted cubic spline (RCS) function was used to investigate the dose-response relationship between the BMI and hypertension. Results: The prevalence of hypertension was 9.91%, followed by 11.71% in males and 7.9% in females, respectively. Compared to the normal weight group, the odds risk (OR) for hypertension in the overweight group was 1.729, and the OR for hypertension in the obesity group was 3.089. After adjusting for potential confounders, the adjusted ORs were 1.620 [95% confidence interval (CI): 1.457-1.800] in the overweight group and 3.092 (95% CI: 2.824-3.385) in the obesity group. According to the multivariate RCS regression analysis, there was a significant non-linear dose-response association between the BMI and the risk of hypertension (all P-values for non-linear < 0.001). Conclusion: The dose-response relationship analysis showed that the association strength of hypertension increased non-linearly along with the continuous change of BMI in children and adolescents.

Ultrasound-guided percutaneous microwave ablation for hepatocellular carcinoma adjacent to large vessels: a propensity score matching analysis.

PURPOSE: This study aimed to compare the efficacy and safety of ultrasound-guided percutaneous microwave ablation (MWA) for hepatocellular carcinoma (HCC) adjacent to large vessels with those far from large vessels. METHODS: The clinical data of patients who underwent ultrasound-guided percutaneous MWA for HCC were retrospectively analyzed between January 2011 and December 2018 in Shengjing Hospital. Patients with HCC adjacent to large vessels were included in the Vessel group, the remaining patients were included in the Control group. Propensity score matching analysis was used to reduce confounding bias. The rates of complete ablation, local recurrence, recurrence-free survival (RFS), overall survival (OS) and complications were compared between the two groups. RESULTS: A total of 134 patients with 157 nodules (size range, 0.6-3.8 cm) were enrolled in this study, 23 in the Vessel group and 111 in the Control group. A total of 21 patients in the Vessel group (91.3%) and 105 patients in the Control group (94.6%) achieved complete ablation (p = .902). Following 1:2 propensity score matching, 22 patients were included in the Vessel group and 40 patients were enrolled in the Control group. Local recurrence was observed in 2 (9.1%) patients in the Vessel group and 5 (12.5%) in the Control group (p = .86). No significant difference in local recurrence rate, RFS and OS were observed between the two groups. CONCLUSIONS: Ultrasound-guided percutaneous MWA appears to be a safe procedure and can achieve comparable oncological efficacy for HCC abutting large vessels.

Beneficial impact of microwave ablation-assisted laparoscopic hepatectomy in cirrhotic hepatocellular carcinoma patients: a propensity score matching analysis.

PURPOSE: In this study, we evaluated the efficacy of microwave ablation-assisted laparoscopic hepatectomy (MLH) for the management of hepatocellular carcinoma (HCC) in cirrhotic patients. METHODS: Data from HCC patients with liver cirrhosis who underwent laparoscopic hepatectomy (LH) or MLH in Shengjing Hospital (Shenyang, China) were retrospectively analyzed from January 2013 to June 2017. The demographic characteristics, clinical features, intraoperative parameters and surgical outcomes were analyzed and compared. Propensity scores matching (PSM) analysis was used to minimize bias. RESULTS: A total of 54 patients were enrolled in the MLH group and 39 patients in the LH group. Following 1:1 matching by PSM analysis, 26 patients were selected from each group. Compared to the LH group, patients in the MLH group had significantly decreased intraoperative bleeding (48.0 vs. 203.9 ml, p < .0001) and reduced demand for hepatic inflow occlusion (0 vs. 6, p = .009). No significant difference was observed in average operation time (155.7 vs. 148.5 min) and postoperative hospitalization time (8.3 vs. 9.3 d) between the MLH and LH groups. Similarly, the 1-year and 3-year recurrence-free survival (RFS) rates as well as the 1-year and 3-year overall survival (OS) rates of the MLH and LH groups were not significantly different (83.1 vs. 82.4% and 64.6 vs. 36.6% as well as 100 vs. 95.8% and 93.8 vs. 59.1%, respectively: p > .05). CONCLUSIONS: MLH significantly decreased intraoperative bleeding and reduced the need for hepatic occlusion without compromising the surgical outcome. Therefore, microwave ablation could be a valuable tool for LH in HCC patients with cirrhosis.

Habitat-mediated, density-dependent dispersal strategies affecting spatial dynamics of populations in an anthropogenically-modified landscape.

A major challenge in managing natural populations in ecosystems is understanding and predicting the complexity and consequences of population dispersal. Although many studies have documented the importance of conspecific density and habitat quality in the dispersal process, we lack an understanding of how to integrate these factors in determining the spatial dynamics of populations or how habitat quality can mediate density-dependent dispersal. In this study, we propose a Habitat-mediated, Density-dependent, Spatial Population Dynamics model (HD-SPDM), in which we combined a Habitat Suitability Index (HSI) with a migration function, to explore the emergent effects of habitat mediated, density-dependent dispersal strategies on the spatial dynamics of a population. Our results show that habitat condition (based on HSI score) can influence ranges in conspecific density (which in turn can alter spatial patterns of populations distributed in homogeneous patches). We tested this model using the spatial distribution of Chinese mitten crab in the Yangtze River Estuary, which has been subjected to excessive sea reclamations over time, this allowed us to obtain insight into spatial distribution of population by determining how habitat-mediated, density-dependent dispersal at a small scale interacts with habitat heterogeneity and fragmentation at a landscape scale. We found that each progressive sea reclamation reduced suitable habitat area and habitat connectivity in the estuary. However, the model predicts that intermediate intensities of habitat compression and fragmentation could improve habitat utilization somewhat by facilitating population dispersal. Our model could be used to improve resource management of populations being increasingly impacted by anthropogenic alterations.