Angular multiplexed holographic memory system based on moving window on liquid crystal display and its crosstalk analysis

We suggested a new non-mechanical angular multiplexed holographic memory system using a moving window, which was fabricated by controlling the pixels of a liquid crystal display (LCD) electronically. If we use light passed through the window left and right, and up and down, each window makes a reference wave with a different incidence angle and we can store angular-multiplexed holograms. The feasibility of the proposed method was demonstrated through optical experiments and its crosstalk noise analysis was also presented.     

Reversible magnetization and irreversibility line of tri-layer superconductor Ba2Ca2Cu3O6(O,F)2 with Tc∼108 K

We report magnetization measurements of grain-aligned Ba₂Ca₂Cu₃O₆(O,F)₂ with T_c?108 K. The interlayer distance of the material is the shortest among known tri-layer superconductors. Unexpectedly, the magnetization data show that the coupling strength between CuO₂ layers is rather weak. A direct reflection of the weak coupling is highly suppressed irreversibility line, i.e. a broad reversible region in H-T plane. The decoupling field obtained from the irreversibility line is less than 0.1 T, which is comparable with that of quasi two-dimensional superconductor Bi₂Sr₂CaCu₂O_8+δ. Comparison of data with the Hao-Clem model gives characteristic parameters [ξ_ab(0) and λ_ab(0)] and the critical fields [H_c(0) and H_c2^c(0)]. A large value of penetration depth, λ_ab(0)=240 nm reflects a small carrier concentration in CuO₂ planes, and explains the reason of the weak interlayer coupling.     

The roles of glycosphingolipids in the proliferation and neural differentiation of mouse embryonic stem cells

Glycosphingolipids including gangliosides play important regulatory roles in cell proliferation and differentiation. UDP-glucose:ceramide glucosyltransferase (Ugcg) catalyze the initial step in glycosphingolipids biosynthesis pathway. In this study, Ugcg expression was reduced to approximately 80% by short hairpin RNAs (shRNAs) to evaluate the roles of glycosphingolipids in proliferation and neural differentiation of mouse embryonic stem cells (mESCs). HPTLC/immunofluorescence analyses of shRNA-transfected mESCs revealed that treatment with Ugcg-shRNA decreased expression of major gangliosides, GM3 and GD3. Furthermore, MTT and Western blot/immunofluorescence analyses demonstrated that inhibition of the Ugcg expression in mESCs resulted in decrease of cell proliferation (P < 0.05) and decrease of activation of the ERK1/2 (P < 0.05), respectively. To further investigate the role of glycosphingolipids in neural differentiation, the embryoid bodies formed from Ugcg-shRNA transfected mESCs were differentiated into neural cells by treatment with retinoic acid. We found that inhibition of Ugcg expression did not affect embryoid body (EB) differentiation, as judged by morphological comparison and expression of early neural precursor cell marker, nestin, in differentiated EBs. However, RT-PCR/immunofluorescence analyses showed that expression of microtubule- associated protein 2 (MAP-2) for neurons and glial fibrillary acidic protein (GFAP) for glial cells was decreased in neural cells differentiated from the shRNA-transfected mESCs. These results suggest that glycosphingolipids are involved in the proliferation of mESCs through ERK1/2 activation, and that glycosphingolipids play roles in differentiation of neural precursor cells derived from mESCs.     

Derivation of tunneling probabilities for arbitrarily graded potential barriers using modified Airy functions

General expressions of tunneling probability for arbitrarily graded potential barriers are rigorously derived using the modified Airy functions. Three types of graded potential barriers for which exact solutions exist are taken as examples for comparison’s purpose. Results obtained by the proposed method are confirmed to be in fairly good agreement with exact ones, demonstrating the usefulness of the modified Airy functions method.