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- Author or Editor: Li-Hong Xie x
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The problem when a paratopolgical group (or semitopological group) is a topological group is interesting and important. In this paper, we continue to study this problem. It mainly shows that: (1) Let G be a paratopological group and put τ = ω H s(G); then G is a topological group if G is a P τ-space; (2) every co-locally countably compact paratopological group G with ω H s(G) ≦ ω is a topological group; (3) every co-locally compact paratopological group is a topological group; (4) each 2-pseudocompact paratopological group G with ω H s(G) ≦ ω is a topological group. These results improve some results in [11, 13].
Trifolium repens Linn (white clover) is the main host of several economically important thrips species in Yunnan Province, in China. The diversity and relative abundance of thrips found on white clover were surveyed weekly via destructive collections from May 2009–May 2010 in Kunming. The 1786 thrips adults were collected and prepared on slides, eight thrips species were identified. The predominant species was western flower thrips (Frankliniella occidentalis), then followed by Megalurothrips distalis, Thrips flavus, Frankliniella intonsa, Thrips palmi, Thrips hawaiiensis, Thrips tabaci and Megalurothrips usitatus. The largest variation in abundance occurred in Mid-Autumn and late Winter, with Thrips flavus dominant at Mid-Autumn and Megalurothrips distalis dominant at late Winter. The correlativity results showed that the population of western flower thrips was significantly negatively correlated to the population of M. distalis (P<0.01), and no significant correlation was found between the population of western flower thrips and the other thrips (P>0.05) in Summer of 2009. In Spring of 2010, the population of western flower thrips was negatively correlated to the population of M. distalis (P<0.05), and it was no significant correlated to the population of the others thrips (P>0.05). However, no significant correlation was found between the population of western flower thrips and the others thrips (P>0.05) in both autumn and winter of 2009.
Abstract
d-glucosamine at concentration of certain range could kill tumor cells without influencing normal cells. There are also some reports on the antitumor activity of d-glucosamine and its derivatives in murine models. It was therefore postulated that d-glucosamine might have the potential to invade tumor cells. We designed and radiosynthesized a glucosamine derivative, N-(2-[18F]fluoro-4-nitrobenzoyl)glucosamine ([18F]FNBG([18F]7)). Evaluations in vitro and in vivo were performed on tumor bearing mice. Excitingly, the radiochemical purity of [18F]FNBG([18F]7) was 99%, and besides the best radiochemical yield was up to 35%. The best T/Bl (Tumor/Blood) and T/M (Tumor/Muscle) ratios of [18F]FNBG([18F]7) were 4.40 and 4.84. Although [18F]FNBG([18F]7) deserved further studies, the results revealed it might become a potential PET imaging agent for detecting tumors.
Abstract
Background and aim
Problematic mobile phone use (PMPU) is prevalent and increases the risk for a variety of health problems. However, few studies have explored the neural mechanisms that might render adolescents more or less vulnerable. Here, we aimed to identify whether PMPU is associated with depressive symptoms and whether this relationship is moderated by intrinsic functional connectivity (iFC) which is associated with PMPU.
Methods
In this longitudinal study, we included 238 students (mean age = 19.05, SD = 0.81) that came from a university in Hefei, China. They all finished MRI scans at baseline and completed questionnaires both at baseline and 1 year later. A self-rating questionnaire for adolescent problematic mobile phone use and depression anxiety stress scale-21 were used to assess PMPU and depressive symptoms. We first assessed the relationship between PMPU and depressive symptoms using an autoregressive cross-lagged model. Then, we detected the brain regions that were associated with PMPU. Moreover, the neuroimaging results were extracted to explore whether the iFC of these brain regions moderated the relationship between PMPU and depression.
Results
Consistent with our hypotheses, PMPU was positively associated with depressive symptoms, and the relationship between PMPU and depressive symptoms was moderated by iFC of the left parahippocampal gyrus-right middle temporal gyrus both at baseline and after 1 year (β = 0.554, P = 0.003; β = 0.463, P = 0.016, respectively).
Conclusions
These results advance the understanding of PMPU and suggest that iFC of the left parahippocampal gyrus-right middle temporal gyrus may be a neurobiological contributor to its relationship with depressive symptoms.
