Blooming characteristics and breeding system of an invasive plant Gaura parviflora.

The invasiveness and dissemination of exotic species are strongly influenced by its sexual reproduction characteristics, including blooming characteristics and breeding system. Exploring the association of these sexual reproductive traits with invasiveness would be helpful for revealing the mechanism of its successful invasion. We examined the blooming characteristics and breeding system of Gaura parviflora based on field observations, out-crossing index (OCI) estimation, and hand-pollination experiments. The results showed flowering duration of the G. parviflora population (flowering period) was short (more than 3 months). The life span of single flower (floral longevity) was 40.46 h. Its flower diameter was 3.99 mm. Over seven flowers in bloom per inflorescence and most individuals often bloomed synchronously, which showed a 'mass-flowering pattern'. The changing trend of pollen and stigma vitality was relatively similar, but the duration of stigma vitality was 2 h longer than that of pollen. The stigma and the anthers were close to each other at the initial flowering stage, but the stigma removed from the anthers at the full-blooming stage with the style curving downwards. Many pollinators visited flowers in late full-blooming stage, which were mainly Apis mellifera and Syrphidae spp. Their average visiting frequency was 9.8 times·m-2·h-1. The fruit set in natural pollination after emasculation treatment (insect or wind pollination) was signi-ficantly higher than that in bagged and emasculation treatment, and the treatment of emasculated and bagged with nylon net (excluding insect pollination) could also bear fruits, indicating possible existence of ambophily in G. parviflora. The results of pollen ovule ratio (P/O) mensuration, OCI estimation and hand-pollination experiments showed that its mating system type belonged to additive mixed mating system. So, its characteristics, such as smaller flower size, shorter floral longevity and flowering period, were conducive to allocating more resources to plant growth and seed development, which would help improve its total fitness. The changes of spatial position of male and female organs not only avoided interference between male and female functions, but also created opportunities for stigmas to receive outcross pollen. In addition, the 'mass-flowering pattern' was conducive to attracting pollinators. The pollination mechanism of ambophily was helpful to ensure cross-pollination. The additive mixed mating system could provide double reproductive assurance for this species. These reproductive characteristics were significant for the successful invasion and expansion of G. parviflora.

ß-Caryophyllene Acts as a Ferroptosis Inhibitor to Ameliorate Experimental Colitis.

Macrophage infiltration is one of the main pathological features of ulcerative colitis (UC) and ferroptosis is a type of nonapoptotic cell death, connecting oxidative stress and inflammation. However, whether ferroptosis occurs in the colon macrophages of UC mice and whether targeting macrophage ferroptosis is an effective approach for UC treatment remain unclear. The present study revealed that macrophage lipid peroxidation was observed in the colon of UC mice. Subsequently, we screened several main components of essential oil from Artemisia argyi and found that ß-caryophyllene (BCP) had a good inhibitory effect on macrophage lipid peroxidation. Additionally, ferroptotic macrophages were found to increase the mRNA expression of tumor necrosis factor alpha (Tnf-α) and prostaglandin-endoperoxide synthase 2 (Ptgs2), while BCP can reverse the effects of inflammation activated by ferroptosis. Further molecular mechanism studies revealed that BCP activated the type 2 cannabinoid receptor (CB2R) to inhibit macrophage ferroptosis and its induced inflammatory response both in vivo and in vitro. Taken together, BCP potentially ameliorated experimental colitis inflammation by inhibiting macrophage ferroptosis. These results revealed that macrophage ferroptosis is a potential therapeutic target for UC and identified a novel mechanism of BCP in ameliorating experimental colitis.

[Near-infrared quantum cutting downconversion luminescence of Yb3+ ion cooperative energy transferred from YVO4 matrix donor].

The present manuscript researches the near infrared quantum cutting luminescence phenomena of Yb3+ ion in YVO4 crystal matrix The luminescence spectra, excitation spectra and fluorescence lifetimes were measured. It was found that the excitation of YVO4 crystal matrix energy band by 322.0 nm light can result in the effective secondary cooperative energy transfer of Yba+ ion from the YVO4 crystal matrix It results in the intense 985.5 nm 2F(5/2)-->2F(7/2) near infrared quantum cutting luminescence of Yb3+ ion. Meanwhile, the 430.O nm luminescence intensity of YVO4 crystal matrix decreases greatly. From the experimental measurements, it was found that the lifetime of 430.0 nm fluorescence of (A) Yb(1.5) : YVO4 crystal is tauA = 3.785 s and that of (B) YVO4 crystal is tauB=22.72 s. It was found also that the theoretical efficiency up limit of quantum cutting of (A) Yb(1.5) : YVO4 crystal is about eta1.5%=183-3%.