Design of Virtual Objects Using Transformation Optics

Two structures of virtual targets filled with metamaterials are investigated through transformation optics to tailor the specific electromagnetic fields into desired spatial patterns. One virtual structure is a square column object transformed from a dielectric cylinder and the other virtual structure is a cylinder object transformed from a dielectric square column. Because the electromagnetic parameters in the virtual objects are obtained from real objects by the method of transformation optics, the scattering fields of virtual structures are the same as those of the real objects. The numerical simulations further prove the correction of theoretical results

Towards a Packet Radio Network Single-channel Non-collision Multiple Access Protocol Based on Priority

Multiple Access (MAC) protocol is a key issue in multiple packet radio network self-organization design. To address problems of hidden collision, adjacent collision and inability to effectively access with priority of multiple access protocol caused by multiple-hop, the paper brought out a novel Non-collision Multiple Access (NCMA) protocol that can effectively support access with priority. It also uses RTS/CTS dialog to arrange capture effect with CTS by deterministic slot, but no longer exist collision between RTS and RTS, RTS and CTS, CTS and CTS. The proposed protocol avoids problems of existing protocols that wasting channel resource for RTS/CTS collision in case of light load as well as throughput performance decrease as traditional CSMA under heavy load, thus significantly improving network resource utilization. Analysis result shows that NCMA can break limitation that existing multi-hop packet radio network cannot effectively networking and support priority

Observation of Hybrid-Order Topological Pump in a Kekule-Textured Graphene Lattice

Thouless charge pumping protocol provides an effective route for realizing topological particle transport. To date, the first-order and higher-order topological pumps, exhibiting transitions of edge-bulk-edge and corner-bulk-corner states, respectively, are observed in a variety of experimental platforms. Here, we propose a concept of hybrid-order topological pump, which involves a transition of bulk, edge, and corner states simultaneously. More specifically, we consider a Kekul\'e-textured graphene lattice that features a tunable phase parameter. The finite sample of zigzag boundaries, where the corner configuration is abnormal and inaccessible by repeating unit cells, hosts topological responses at both the edges and corners. The former is protected by a nonzero winding number, while the latter can be explained by a nontrivial vector Chern number. Using our skillful acoustic experiments, we verify those nontrivial boundary landmarks and visualize the consequent hybrid-order topological pump process directly. This work deepens our understanding to higher-order topological phases and broadens the scope of topological pumps.Comment: 5 figure

Altered Gut Microbiota in Myasthenia Gravis

Myasthenia gravis (MG) is an autoimmune-mediated disorder, the etiology of which involves both environmental factors and genetics. While the exact factors responsible for predisposition to MG remain elusive, it is hypothesized that gut microbiota play a critical role in the pathogenesis of MG. This study investigated whether gut microbiota are altered in MG patients by comparing the fecal microbiota profiles of MG patients to those of age- and sex-matched healthy controls. Phylotype profiles of gut microbial populations were generated using hypervariable tag sequencing of the V4 region of the 16S ribosomal RNA gene. Fecal short-chain fatty acids (SCFAs) were assessed by gas chromatographic analyses. The results demonstrated that, compared to the healthy cohort, the gut microbiota of the MG group was changed in terms of the relative abundances of bacterial taxa, with sharply reduced microbial richness, particularly in the genus Clostridium. The fecal SCFA content was significantly lower in the MG group. Furthermore, microbial dysbiosis was closely related to the levels of inflammatory biomarkers in the sera of MG patients

Combination of capecitabine and ludartin inhibits colon cancer growth in mice

Purpose: To investigate the efficacy of capecitabine and ludartin in the treatment of colon cancer in mice.Methods: Mice model of colon cancer was used in this study. Quantitative real-time polymerase chain reaction (Qrt-PCR) was used to quantify the expression of vascular endothelial growth factor (VEGF) mRNA. Micro-vessel density was assessed using immunohistochemical analysis.Results: When administered separately, capecitabine and ludartin treatments significantly suppressed tumor growth in the mice model of colon cancer for 4 weeks, compared to control group. Coadministration of capecitabine and ludartin significantly inhibited tumor growth for 6 weeks (p < 0.05). Symptoms of colon cancer such as weight loss, skin discoloration and leukopenia were observed in untreated control group. However, these symptoms were completely absent in the group treated with combination of capecitabine and ludartin. The combined treatment also prevented colon cancer-induced increase in white blood cell (WBC) count, and increased median survival time of colon cancer mice from 38 to 55 days. Expression of VEGF in combination (capecitabine + ludartin) treatment group was significantly lower than in the control, i.e., untreated group (p ˂ 0.05). The combination treatment group also had significantly lower micro-vessel density in the tumor tissues, compared to the  ntreated control mice (p < 0.05).Conclusion: These results show that a combination treatment of capecitabine and ludartin effectively inhibits colon tumor growth and angiogenesis in mice via a mechanism involving suppression of VEGF expression. Thus, capecitabine and ludartin combination is a potentially  uitable treatment for colon cancer.Keywords: Colon cancer, Mice, Ludartin, Leukopenia, VEGF expression, Angiogenesi