High correlations between plant clonality and ecosystem service functions after management in a chronosequence of evergreen conifer plantations.

Introduction: Climate change and mono-afforestation or mono-reforestation have continuously caused a decline in biodiversity and ecosystem services on forest plantations. Key plant functional traits in forests or plantations may affect ecosystem functions after forest management practices. Plant clonality, a key functional trait, frequently links to biodiversity and ecosystem functions and affects the biodiversity-ecosystem functioning relationship. However, little is known about how plant clonality affects ecosystem functions and services of plantations after forest management. Methods: We conducted a field experiment to discuss the diversity and proportion of clonal plants, plant diversity of the communities, and ecosystem service functions and their relationships under 10 years of close-to-nature (CTN) management, artificial gap management, and control (i.e., without management) in the three stages of C. Lanceolata plantations. Results: Our results showed that CTN and gap management modes significantly facilitated diversity of clonal plants, plant diversity of the communities, and parameters of ecosystem service functions in C. lanceolata plantations. Moreover, CTN management promoted plant community diversity, soil water conservation, and carbon storage the most in the earlier stand stages. Diversity of clonal plants was significantly positively correlated with ecosystem service functions after forest management. Structural equation modeling analysis indicated that forest gap or CTN management indirectly positively affected ecosystem service functions through increasing diversity of clonal woody plants and plant diversity of the communities. Conclusion: Our results indicate a highly positive effect of gap or CTN management on diversity and proportion of clonal plants and on plant diversity of the communities, which link to improvements in ecosystem service functions (i.e., water and soil conservation and carbon storage). The link between forest management, diversity, and ecosystem functions suggests that key functional traits or plant functional groups should be considered to underline the mechanism of traits-ecosystem functioning relationships and the restoration of degraded plantations.

Cross-Linking the Surface of Cured Polydimethylsiloxane via Hyperthemal Hydrogen Projectile Bombardment.

Cross-linking of polydimethylsiloxane (PDMS) is increasingly important with recent focus on its top surface stiffness. In this paper, we demonstrate that hyperthermal hydrogen projectile bombardment, a surface sensitive cross-linking technology, is superior in enhancing the mechanical properties of a cured PDMS surface without significantly degrading its hydrophobicity. Both water contact angle measurements and time-of-flight secondary ion mass spectrometry are used to investigate the variations in surface chemistry and structure upon cross-linking. Using nanoindentation and atomic force microscopy, we confirm that the thickness of the cross-linked PDMS is controllable by the bombardment time, which opens opportunities for tuning cross-linking degree in compliance with arising requirements from the practice.

[Intestinal obstruction caused by gallstone: report of 5 cases and review of the literature].

OBJECTIVE: To explore clinical features, diagnostic methods and treatment of gallstone ileus. METHODS: Clinical data of 5 patients with gallstone ileus were analyzed retrospectively. Pertinent literature from China between 2000 and 2009 were reviewed. The disease onset, clinical manifestations, imaging characteristics, diagnosis and treatment of gallstone ileus were studied. RESULTS: Four out of 5 patients were female aged over 60, of whom 3 had a previous history of cholelithiasis, 2 had a history of cholangiojejunostomy internal drainage procedure. Four patients underwent enterotomy and gallstone extraction combined with hepatobiliary operation, while one underwent enterotomy alone. There was no postoperative recurrence. A review of the literature from China revealed 441 cases with intestinal obstruction caused by gallstone, consisting 1.15% of all the cases with bowel obstruction. 67.12% were female. 73.56% were elderly. 87.92% were from cystoenteral fistula. Site of bowel obstruction in ileum was 64.17% of the cases. 71.89% were misdiagnosed with other types of obstruction. Two hundred twenty-five patients underwent enterotomy and gallstone extraction combined with hepatobiliary operation, which carried a lower rate of postoperative recurrence and malignancy (P<0.05) than enterotomy alone. There were no statistical significant differences in the occurrence of postoperative cystoenteral fistula, wound infection, pulmonary infection, cure rate, and mortality(P>0.05). CONCLUSIONS: The incidence of gallstone ileus is low and more common in female elderly. The gallstones often drain through cystoenteral fistula and lodge in the ileum. Enterotomy without hepatobiliary operation is associated with potential risk of recurrence and development of gallbladder malignancy. Combined hepatobiliary operation is recommended in patients without significant comorbidities.