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The magnetic configuration of a submicrometer Ni 88 Fe 12 permalloy island has been quantitatively mapped by off-axis electron holography. The two main contributions to the electron-optical phase shift, namely the phase shifts induced by the electrostatic and magnetic potentials, including fringing fields, were separated by inverting the specimen of 180°with respect to the electron beam and directly measuring the mean inner potential. A quantitative map of the projected magnetic induction in the sample was thereby retrieved and compared to results of micromagnetic and electromagnetic calculations, providing the minimum-energy configuration and the phase shift, respectively.

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The rocky desertification is one of three major ecological problems in the karst areas in southwestern China. Vegetation fraction, bare soil, and bare rock are main typical surface characteristics obtained from remote sensing data when evaluating rocky desertification in these areas. How to estimate vegetation coverage more precisely is a challenging topic because the issues of complex surface coverage, highly spatial heterogeneity, and mixed-pixels should be addressed. Hyperspectral pixel unmixing is a better approach to solve these issues. In this paper, the Hyperion hyperspectral remotely sensed image is used as the source data, vegetation, soil, and rock are selected as three typical land cover features, and the pixel purity index (PPI) is utilized to distill the endmember spectral. Then, the pixel unmixing methods, including matched filtering (MF) and mixture tuned matched filtering (MTMF) are adopted to estimate vegetation coverage of the studied karst area, respectively. The results show that: 1) the maximum deviation between the ground-surveyed vegetation fraction and the MTMF-inversed one is acceptable, and so are the deterministic coefficient and the root mean square error (RMSE); 2) the MTMF-inversed results are more accurate than the ones inversed from the MF method and the MTMF-inversed vegetation coverage can be used to estimate the actual vegetation fraction. The results also demonstrate the applicability of the MTMF method in evaluating vegetation fraction in the karst regions.Index Terms-Hyperspectral data, karst area, pixel purity index (PPI), pixel unmixing, vegetation fraction.

Background: Toll-like receptor-7 (TLR7), which recognizes viral single-stranded RNA, can trigger immune complex glomerulonephritis in experimental lupus erythematosus. However, whether it modulates dendritic cells (DCs) phenotype and regulatory T cells (Treg) function is incompletely understood. Method: Splenocytes and bone marrow DCs were obtained from 5- and 20-week-old female MRL^lpr/lpr mice and C57BL/6 mice. In addition, to understand the response of Treg and DCs to TLR7 ligation in vivo, 16-week-old female MRL^lpr/lpr and C57BL/6 mice were distributed into two groups with or without intraperitoneal injections of TLR7 ligand every other day. Results: After activation with the TLR7 ligand imiquimod in vivo and vitro, DCs from imiquimod-treated MRL/lpr mice showed an altered costimulatory profile, with decreased induction of CD80, CD86, and MHCII expression, comparing to age-matched C57BL/6 control mice. There was no significant difference in the numbers of CD₄⁺CD₂₅⁺Foxp3⁺ cells after TLR7 ligation by imiquimod in MRL^lpr/lpr and control mice. Immunostaining of kidney sections of nephritic MRL/lpr mice revealed that CD11c was expressed in the infiltrated tubulointerstitial cells, and confocal microscopic analysis of renal CD11c⁺MHCII⁺, CD11c⁺CD80⁺, and CD11c^+​CD86⁺ cells showed an immature phenotype with low levels of CD80, CD86, and MHCII in imiquimod-treated MRL/lpr mice. There was no difference in the number of Foxp3 positive cells in kidneys between the imiq‑uimod and vehicle-treated groups. Conclusions: Our results suggest that activation of TLR7 exacerbated lupus nephritis by modulating the abnormally costimulatory phenotype of dendritic cells and functions of Treg in MRL/lpr mice.

The English and Chinese reading proficiency of 1376 Grade 4 students in 24 Hong Kong primary schools were assessed using measures developed for the Progress in International Reading Literacy Study. Students’ parents provided information about home reading activities (HRA) aimed at supporting their children’s reading prior to them entering school (“early home reading activities”, EHRA) and during Grade 4 (“home reading activities”). Results indicated that EHRA was a stronger predictor of reading performance in both Chinese and English than HRA. Moreover, ‘typical’ HRA such as reading books, telling stories and singing songs were found to be predictive of reading performance in both Chinese and English. In English, in addition, playing word games or character puzzles were also activities beneficial to reading performance. Together, these results provide evidence for the beneficial effects of traditional early childhood activities at home such as book reading, telling stories and singing songs for reading performance in later primary school in children’s first as well as second language.

Dendritic cells (DCs) play a critical role in the pathogenesis of autoimmune diseases including multiple sclerosis, and targeting DCs’ cytokines production is an important strategy for autoimmune diseases treatment. By establishing a high-throughput screening system, we analyzed LOPAC drug library to identify drugs that control the secretion of IL-6 by DCs, we selected the most likely candidate drug, BVDU, and found that it affected not only IL-6 production, but also that of IL-12, IL-1β during the DCs differentiation and maturation. The mechanism studies showed that BVDU treatment restricted the phosphorylation of MAP kinase, which played an important role in DC cytokine production. We further assessed the in vivo therapeutic potentials of BVDU on mouse models including EAE and STZ-induced T1D, and found that BVDU treated EAE mice exhibited significantly lower EAE clinical scores, decreased leukocyte infiltration in central nervous system lesions, and reduced demyelination. As in T1D mice, BVDU treatment also showed promising therapeutic effects based on both alleviated disease symptoms and tissue pathogenesis. More interestingly, the modulating effect of BVDU on IL-6 production was further verified in human primary DCs. The above data supported the promising application of our screen model, and also the potential of BVDU for autoimmune diseases therapy.

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