5,476 research outputs found
Interaction induced ferro-electricity in the rotational states of polar molecules
We show that a ferro-electric quantum phase transition can be driven by the
dipolar interaction of polar molecules in the presence a micro-wave field. The
obtained ferro-electricity crucially depends on the harmonic confinement
potential, and the resulting dipole moment persists even when the external
field is turned off adiabatically. The transition is shown to be second order
for fermions and for bosons of a smaller permanent dipole moment, but is first
order for bosons of a larger moment. Our results suggest the possibility of
manipulating the microscopic rotational state of polar molecules by tuning the
trap's aspect ratio (and other mesoscopic parameters), even though the later's
energy scale is smaller than the former's by six orders of magnitude.Comment: 4 pages and 4 figure
Probing onset of strong localization and electron-electron interactions with the presence of direct insulator-quantum Hall transition
We have performed low-temperature transport measurements on a disordered
two-dimensional electron system (2DES). Features of the strong localization
leading to the quantum Hall effect are observed after the 2DES undergoes a
direct insulator-quantum Hall transition with increasing the perpendicular
magnetic field. However, such a transition does not correspond to the onset of
strong localization. The temperature dependences of the Hall resistivity and
Hall conductivity reveal the importance of the electron-electron interaction
effects to the observed transition in our study.Comment: 9 pages, 4 figure
High expression FUT1 and B3GALT5 is an independent predictor of postoperative recurrence and survival in hepatocellular carcinoma.
Cancer may arise from dedifferentiation of mature cells or maturation-arrested stem cells. Previously we reported that definitive endoderm from which liver was derived, expressed Globo H, SSEA-3 and SSEA-4. In this study, we examined the expression of their biosynthetic enzymes, FUT1, FUT2, B3GALT5 and ST3GAL2, in 135 hepatocellular carcinoma (HCC) tissues by qRT-PCR. High expression of either FUT1 or B3GALT5 was significantly associated with advanced stages and poor outcome. Kaplan Meier survival analysis showed significantly shorter relapse-free survival (RFS) for those with high expression of either FUT1 or B3GALT5 (P = 0.024 and 0.001, respectively) and shorter overall survival (OS) for those with high expression of B3GALT5 (P = 0.017). Combination of FUT1 and B3GALT5 revealed that high expression of both genes had poorer RFS and OS than the others (P < 0.001). Moreover, multivariable Cox regression analysis identified the combination of B3GALT5 and FUT1 as an independent predictor for RFS (HR: 2.370, 95% CI: 1.505-3.731, P < 0.001) and OS (HR: 2.153, 95% CI: 1.188-3.902, P = 0.012) in HCC. In addition, the presence of Globo H, SSEA-3 and SSEA-4 in some HCC tissues and their absence in normal liver was established by immunohistochemistry staining and mass spectrometric analysis
Insulator, semiclassical oscillations and quantum Hall liquids at low magnetic fields
Magneto-transport measurements are performed on two-dimensional GaAs electron
systems to probe the quantum Hall (QH) effect at low magnetic fields.
Oscillations following the Shubnikov-de Haas (SdH) formula are observed in the
transition from the insulator to QH liquid when the observed almost
temperature-independent Hall slope indicates insignificant interaction
correction. Our study shows that the existence of SdH oscillations in such a
transition can be understood based on the non-interacting model.Comment: 17 page
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