In attempts to fabricate thermally stable second-order nonlinear polymer thin films, we have investigated the second harmonic generation (SHG) from both nonlinear polymer and guest-host thin films. We have also invest...In attempts to fabricate thermally stable second-order nonlinear polymer thin films, we have investigated the second harmonic generation (SHG) from both nonlinear polymer and guest-host thin films. We have also investigated the role of capping on the SHG, temporal stability and relaxation of dipole alignment. Corona poling techniques were employed to orient the dopants into the noncentrosymmetric structure required to obtain the SHG. The effect of capping with a polymeric encapsulant below the glass transition temperature of the polymers on the unpoled and corona poled thin films was studied. Capping of the nonlinear polymer and guest host thin films have resulted in high SHG with good temporal stability. SHG signal falls drastically during the first 8 days after poling while no further significant decay in SHG signal was observed after about 33 days. Our investigations have identified the characteristics required for a good encapsulant on a non-con-ductive surface.展开更多
The intraosseous benign notochordal cell tumor (BNCT) is an intravertebral lesion derived from notochordal tissue. The notochord develops in humans during the third week of embryonic life and persists in adults as the...The intraosseous benign notochordal cell tumor (BNCT) is an intravertebral lesion derived from notochordal tissue. The notochord develops in humans during the third week of embryonic life and persists in adults as the nucleus pulposus of the vertebral disks. The most common locations of such tumors are the saccrococcygeal region and the skull base. Most tumors are asymptomatic and small. Magnetic resonance imaging is useful in their detection and precise localization. Histologically, these lesions consist of sheets of adipocyte-like vacuolated or less vacuolated eosinophilic tumor cells with eccentrically located round nuclei without myxoid matrix. The tumor cells express the epithelial markers, vimentin and S100 protein. Main differential diagnosis is chordoma. Intraosseous BNCT do not require any surgical management and should be recognized by pathologists to prevent unnecessary radical surgery. These lesions should be followed-up with conventional MRI.展开更多
文摘In attempts to fabricate thermally stable second-order nonlinear polymer thin films, we have investigated the second harmonic generation (SHG) from both nonlinear polymer and guest-host thin films. We have also investigated the role of capping on the SHG, temporal stability and relaxation of dipole alignment. Corona poling techniques were employed to orient the dopants into the noncentrosymmetric structure required to obtain the SHG. The effect of capping with a polymeric encapsulant below the glass transition temperature of the polymers on the unpoled and corona poled thin films was studied. Capping of the nonlinear polymer and guest host thin films have resulted in high SHG with good temporal stability. SHG signal falls drastically during the first 8 days after poling while no further significant decay in SHG signal was observed after about 33 days. Our investigations have identified the characteristics required for a good encapsulant on a non-con-ductive surface.
文摘The intraosseous benign notochordal cell tumor (BNCT) is an intravertebral lesion derived from notochordal tissue. The notochord develops in humans during the third week of embryonic life and persists in adults as the nucleus pulposus of the vertebral disks. The most common locations of such tumors are the saccrococcygeal region and the skull base. Most tumors are asymptomatic and small. Magnetic resonance imaging is useful in their detection and precise localization. Histologically, these lesions consist of sheets of adipocyte-like vacuolated or less vacuolated eosinophilic tumor cells with eccentrically located round nuclei without myxoid matrix. The tumor cells express the epithelial markers, vimentin and S100 protein. Main differential diagnosis is chordoma. Intraosseous BNCT do not require any surgical management and should be recognized by pathologists to prevent unnecessary radical surgery. These lesions should be followed-up with conventional MRI.
