Environmental filtering and dispersal limitation jointly shaped the taxonomic and phylogenetic beta diversity of natural forests in southern China.

Aim: The mechanisms underlying the maintenance of biodiversity remain to be elucidated. Taxonomic diversity alone remains an unresolved issue, especially in terms of the mechanisms of species co-existence. We hypothesized that phylogenetic information could help to elucidate the mechanism of community assembly and the services and functions of ecosystems.

[Foliar stable carbon isotope composition and water use efficiency of plant in the Karst seasonal rain forest.].

To enrich niche partition and species coexistence theory in karst seasonal rain forest, and provide reference for species selection and configuration for rocky desertification control, we exami-ned foliar stable carbon isotope composition (δC) and water use efficiency (WUE) of the representative species in different habitats and the same tree species in different habitats. The results showed that foliar δC value in karst seasonal rain forest ranged from -34.13‰ to -29.

Design, synthesis and biological evaluation of brain-specific glucosyl thiamine disulfide prodrugs of naproxen.

Glucosyl derivates exhibited favorable distribution to the brain. However, bidirectional transport of glucose transporter 1 might decrease concentrations of the prodrugs in brain before the release of parent drugs. To overcome this defect, glucosyl thiamine disulfide prodrugs 1a-1c incorporating naproxen were designed and synthesized.

[Spatial patterns of and specific correlations between dominant tree species in a karst evergreen and deciduous broadleaved mixed forest in Mulun Karst National Nature Reserve].

In order to understand the biological characteristics and specific correlations of dominant tree species in a karst characteristic evergreen and deciduous broad-leaved mixed forest in Mulun National Nature Reserve of Guangxi, a point pattern analysis was made on the spatial distribution patterns and inter- and intraspecific correlations of four dominant species in a one-hectare plot. Among the four species, Boniodendron minius dominated in tree sublayer I, while Ligustrum japonicum, Sinosideroxylon wightianum, and Rapanea kwangsiensis dominated in tree sublayers II and III. All the four species had a clumped distribution at scale <10 m, a transition from clumped to random distribution at scale 10-25 m, and a random or regular distribution at scale >25 m.

[Changes of serum reproductive hormones with aging among healthy males in a community population of Hebei Province].

Objective: To investigate the changes of serum reproductive hormones with male aging and to compare the differences in the hormone levels among different age groups or between township and rural males of the same age group.

Methods: Using cluster and stratified sampling, we recruited 434 healthy old and middle-aged (40-69 years) males, 198 from the township and 236 from the rural communities. We determined the concentrations of serum total testosterone (tT), luteinizing hormone (LH) and sex hormone binding globulin (SHBG), free testosterone (fT), bio-available testosterone (Bio-T), and obtained the testosterone secretion index (TSI) and free testosterone index (fTI).