Facing the demands of biodiversity conservation and ecosystem service improvement, the spatial pattern optimization of nature reserves has always been a research topic of interest. However, there remains a lack of methodological guidance in the planning of nature reserves and the surrounding areas. To promote the landscape sustainability of nature reserves, we constructed ecological security patterns (ESPs) with two scenarios as a case study in Wenchuan, China. In detail, the ecological sources were identified by ecosystem service evaluation, and the resistance surface was characterized by the habitat quality. The ecological corridors were determined based on circuit theory and the minimum cumulative resistance model. The ecological sources were mainly aggregated in the protected areas, with an area of more than 1000 ha; the high-resistance values were mainly in the area with dense roads or high elevation. There were 21 corridors in the scenario of only optimizing the nature reserve, while 31 corridors were identified when considering non-nature reserves, and the landscape connectivity was enhanced accordingly. The result supported constructing the ESPs between nature and non-nature reserves in Wenchuan to further protect pandas, and a methodological contribution was made to understand the differences of ESPs between them, thus supporting a methodological formulation of sustainable landscape patterns.

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The atomic mechanisms of the melting process of gold nanoparticles were investigated by molecular dynamics simulations. Melting under a high heating rate is found to be much different from the near equilibrium melting and is a typical overheating process. The melting begins with the formation of a premelting layer near the surface, and the interface of the solid and premelting layer drives the nucleation of the liquid into the interior of nanoparticles. The high heating rate causes solid−liquid coexistence in a large temperature interval. These imply that the melting process can be controlled effectively by different heating ways.

Background Postsurgical patients’ oral feeding begins with clear fluids 1–3 days after surgery. This might not be sufficiently nutritious to boost the host immune system and provide sufficient energy in gastric neoplastic patients to achieve the goal of enhanced recovery after surgery (ERAS). Our objective was to analyze the significance of early postoperative feeding tubes in boosting patients’ immunity and decreasing incidence of overall complications and hospital stay in gastric cancer patients’ post-gastrectomy. Methods From January 2005 to May 24, 2019, PubMed and Cochrane databases were searched for studies involving enteral nutrition (EN) feeding tubes in comparison to parenteral nutrition (PN) in gastric cancer patients undergoing gastrectomy for gastric malignancies. Relative risk (RR), mean difference (MD), or standard mean difference (SMD) with 95% confidence interval (CI) were used to estimate the effect sizes, and heterogeneity was assessed by using Q and χ 2 statistic with their corresponding P values. All the analyses were performed with Review Manager 5.3 and SPSS version 22. Results Nine randomized trials ( n = 1437) and 5 retrospective studies ( n = 421) comparing EN feeding tubes and PN were deemed eligible for the pooled analyses, with a categorized time frame of PODs ≥ 7 and PODs < 7. Ratio of CD4+/CD8+ in EN feeding tubes was the only outcome of PODs < 7, which showed significance (MD 0.22, 95% CI 0.18–0.25, P < 0.00001). Regarding other immune indicators, significant outcomes in favor of EN feeding tubes were measured on POD ≥ 7: CD3+ (SMD 1.71; 95% CI 0.70, 2.72; P = 0.0009), CD4+ (MD 5.84; 95% CI 4.19, 7.50; P < 0.00001), CD4+/CD8+ (MD 0.28; 95% CI 0.20; 0.36, P < 0.00001), NK cells (SMD 0.94; 95% CI 0.54, 1.30; P < 0.00001), nutrition values, albumin (SMD 0.63; 95% CI 0.34, 0.91; P < 0.001), prealbumin (SMD 1.00; 95% CI 0.52, 1.48; P < 0.00001), and overall complications (risk ratio 0.73 M-H; fixed; 95% CI 0.58, 0.92; P = 0.006). Conclusion EN feeding tube support is an essential intervention to elevate patients’ immunity, depress levels of inflammation, and reduce the risk of complications after gastrectomy for gastric cancer. Enteral nutrition improves the innate immune system and nutrition levels but has no marked significance on certain clinical outcomes. Also, EN reduces the duration of hospital stay and cost, significantly.