Hybrid Plasmonics Slot THz Waveguide for Subwavelength Field Confinement and Crosstalk between Two Waveguides

The slot waveguide has attracted considerable attention because of its ability to confine and guide electromagnetic energy at the subwavelength scale beyond the diffraction limit. We propose a novel terahertz slot waveguide structure to achieve a better tradeoff between propagation length and field confinement capacity, the novel waveguide consisting of a two slot structure. The performances of terahertz waveguides were investigated using the finite-element method. The results demonstrated that the hybrid slot waveguide (HSW) provides significantly enhanced field confinement in low index slot regions: more than five times that of traditional low index slot waveguides (LISWs). An optimized HSW structure was achieved by tuning the tradeoff between mode confinement and propagation length. We also showed that its integration in conventional planar waveguide circuits was greatly improved compared with the LISWs, by comparing their crosstalk. The proposed new HSW structure has great potential to enable THz production of compact integration and could lead to true semiconductor-basedTHz applications with high performance.Electronic Components, Technology and Material

A CMOS-Compatible Hybrid Plasmonic Slot Waveguide With Enhanced Field Confinement

The emerging field of nanophotonics requires plasmonic devices to be fully compatible with semiconductor fabrication techniques. However, very few feasible practical structures exist at present. Here, we propose a CMOS-compatible hybrid plasmonic slot waveguide (HPSW) with enhanced field confinement. Our simulation results show that the HPSW exhibits significantly enhanced field confinement as compared with the traditional low-index slot waveguides and the hybrid metal dielectric slot waveguides. By controlling the thicknesses of different layers, an optimized HPSW structure with a better tradeoff between field confinement and propagation length has been simultaneously achieved.Electronic Components, Technology and Material

Brain structural plasticity in survivors of a major earthquake

Background: Stress responses have been studied extensively in animal models, but effects of major life stress on the human brain remain poorly understood. The aim of this study was to determine whether survivors of a major earthquake, who were presumed to have experienced extreme emotional stress during the disaster, demonstrate differences in brain anatomy relative to individuals who have not experienced such stressors. Methods: Healthy survivors living in an area devastated by a major earthquake and matched healthy controls underwent 3-dimentional high-resolution magnetic resonance imaging (MRI). Survivors were scanned 13-25 days after the earthquake; controls had undergone MRI for other studies not long before the earthquake. We used optimized voxel-based morphometry analysis to identify regional differences of grey matter volume between the survivors and controls. Results: We included 44 survivors (17 female, mean age 37 [standard deviation (SD) 10.6] yr) and 38 controls (14 female, mean age 35.3 [SD 11.2] yr) in our analysis. Compared with controls, the survivors showed significantly lower grey matter volume in the bilateral insula, hippocampus, left caudate and putamen, and greater grey matter volume in the bilateral orbitofrontal cortex and the parietal lobe (all p < 0.05, corrected for multiple comparison). Limitations: Differences in the variance of survivor and control data could impact study findings. Conclusion: Acute anatomic alterations could be observed in earthquake survivors in brain regions where functional alterations after stress have been described. Anatomic changes in the present study were observed earlier than previously reported and were seen in prefrontal-limbic, parietal and striatal brain systems. Together with the results of previous functional imaging studies, our observations suggest a complex pattern of human brain response to major life stress affecting brain systems that modulate and respond to heightened affective arousal

Establishment of a Cell Line from Chinese Soft-shelled Turtle Pelodiscus sinensis with the Practicability of Transfection and Viral Replication

continuous cell line derived from extracranial carotid artery of the Chinese soft-shelled turtle Pelodiscus sinensis was established and characterized. It was named as STA (soft-shelled turtle artery) cell line. The cells were muscle-cell like, and were stained with antibody against smooth muscle myofilament marker, a-smooth muscle actin. These cells had a normal diploid chromosome number of 2n = 66, and their 12S rRNA and 16S rRNA sequences shared 99% identity with ones of the turtle in database. The cell line can be cultured well in media DMEM/F12 or M199 supplemented with 10% FBS at 28 C. It was further demonstrated that the cells were transfected successfully with pTurbo plasmid, with a transfection efficiency being over 30%. The soft-shelled turtle iridovirus (STIV) propagated in the cell line, causing typical CPE with the formation of inclusion bodies. It is suggested that the established STA cell line provides a convenient platform for studying the pathogenesis of STIV and biological aspects of the turtle.continuous cell line derived from extracranial carotid artery of the Chinese soft-shelled turtle Pelodiscus sinensis was established and characterized. It was named as STA (soft-shelled turtle artery) cell line. The cells were muscle-cell like, and were stained with antibody against smooth muscle myofilament marker, a-smooth muscle actin. These cells had a normal diploid chromosome number of 2n = 66, and their 12S rRNA and 16S rRNA sequences shared 99% identity with ones of the turtle in database. The cell line can be cultured well in media DMEM/F12 or M199 supplemented with 10% FBS at 28 C. It was further demonstrated that the cells were transfected successfully with pTurbo plasmid, with a transfection efficiency being over 30%. The soft-shelled turtle iridovirus (STIV) propagated in the cell line, causing typical CPE with the formation of inclusion bodies. It is suggested that the established STA cell line provides a convenient platform for studying the pathogenesis of STIV and biological aspects of the turtle

IFN-gamma in turtle: Conservation in sequence and signalling and role in inhibiting iridovirus replication in Chinese soft-shelled turtle Pelodiscus sinensis

The IFN-gamma gene was identified in a turtle, the Chinese soft-shelled turtle, Pelodiscus sinensis, with its genome consisting of 4 exons and 3 introns. The deduced amino acid sequence of this gene contains a signal peptide, an IFN-gamma family signature motif (130)IQRKAVNELFPT, an NLS motif (KRKR)-K-155 and three potential N-glycosylation sites. As revealed by real-time quantitative PCR, the gene was constitutively expressed in all tested organs/tissues, with higher level observed in blood, intestine and thymus. An induced expression of IFN-gamma at mRNA level was observed in peripheral blood leucocytes (PBLs) in response to in vitro stimulation of LPS and PolyI:C. The overexpression of IFN-gamma in the Chinese soft-shelled turtle artery (STA) cell line resulted in the increase in the expression of transcriptional regulators, such as IRF1, IRF7 and STAT1, and antiviral genes, such as Mx, PKR, implying possibly the existence of a conserved signalling network and role for IFN-gamma in the turtle. Furthermore, the infection of soft-shelled turtle iridovirus (STIV) in the cell line transfected with IFN-gamma may cause the cell death as demonstrated with the elevated lactate dehydrogenase (LDH) level and cell mortality. However, the mechanism involved in the antiviral activity may require further investigation. (C) 2013 Elsevier Ltd. All rights reserved.The IFN-gamma gene was identified in a turtle, the Chinese soft-shelled turtle, Pelodiscus sinensis, with its genome consisting of 4 exons and 3 introns. The deduced amino acid sequence of this gene contains a signal peptide, an IFN-gamma family signature motif (130)IQRKAVNELFPT, an NLS motif (KRKR)-K-155 and three potential N-glycosylation sites. As revealed by real-time quantitative PCR, the gene was constitutively expressed in all tested organs/tissues, with higher level observed in blood, intestine and thymus. An induced expression of IFN-gamma at mRNA level was observed in peripheral blood leucocytes (PBLs) in response to in vitro stimulation of LPS and PolyI:C. The overexpression of IFN-gamma in the Chinese soft-shelled turtle artery (STA) cell line resulted in the increase in the expression of transcriptional regulators, such as IRF1, IRF7 and STAT1, and antiviral genes, such as Mx, PKR, implying possibly the existence of a conserved signalling network and role for IFN-gamma in the turtle. Furthermore, the infection of soft-shelled turtle iridovirus (STIV) in the cell line transfected with IFN-gamma may cause the cell death as demonstrated with the elevated lactate dehydrogenase (LDH) level and cell mortality. However, the mechanism involved in the antiviral activity may require further investigation. (C) 2013 Elsevier Ltd. All rights reserved