319 research outputs found
Spontaneous Breakdown of Superhydrophobicity
In some cases water droplets can completely wet micro-structured
superhydrophobic surfaces. The {\it dynamics} of this rapid process is analyzed
by ultra-high-speed imaging. Depending on the scales of the micro-structure,
the wetting fronts propagate smoothly and circularly or -- more interestingly
-- in a {\it stepwise} manner, leading to a growing {\it square-shaped} wetted
area: entering a new row perpendicular to the direction of front propagation
takes milliseconds, whereas once this has happened, the row itself fills in
microseconds ({\it ``zipping''})Comment: Accepted for publication in Physical Review Letter
Dynamics of the spontaneous breakdown of superhydrophobicity
Drops deposited on rough and hydrophobic surfaces can stay suspended with gas
pockets underneath the liquid, then showing very low hydrodynamic resistance.
When this superhydrophobic state breaks down, the subsequent wetting process
can show different dynamical properties. A suitable choice of the geometry can
make the wetting front propagate in a stepwise manner leading to {\it
square-shaped} wetted area: the front propagation is slow and the patterned
surface fills by rows through a {\it zipping} mechanism. The multiple time
scale scenario of this wetting process is experimentally characterized and
compared to numerical simulations.Comment: 7 pages, 5 figure
Higher T central and lower effector memory cells in bipolar disorder:A differentiation abnormality?
The aim of this study was to elucidate the nature of T cell abnormalities in bipolar disorder (BD). With the use of multicolor flow cytometry, we first quantified the composition of the different memory and pro-inflammatory immune subpopulations in samples of 58 patients with BD and compared them to 113 healthy controls. Second, to assess if cytomegalovirus infection was related to the resulted immune subpopulation compositions in the two groups, we measured cytomegalovirus-specific antibodies in serum. Thirdly, we assessed differences between the two groups in the serum levels of the immune cell differentiation factor interleukin-7. Compared to healthy controls, patients showed significantly higher T helper-17, T regulatory and T central memory cells (CD4+ and CD8+). Besides, patients showed significantly lower CD4+ T effector memory and CD4+ T effector memory re-expressing RA cells. Cytomegalovirus infection was not related to the observed abnormalities, with the exception of T helper-17 cells. This immune subpopulation was significantly higher only in patients seropositive to cytomegalovirus infection. Finally, interleukin-7 levels were significantly lower in BD compared to healthy controls. In conclusion, the aberrant levels of T memory cell populations in BD may suggest a T cell differentiation abnormality. The role of interleukin-7 in this putative abnormality should be further investigated.</p
Higher T central and lower effector memory cells in bipolar disorder:A differentiation abnormality?
The aim of this study was to elucidate the nature of T cell abnormalities in bipolar disorder (BD). With the use of multicolor flow cytometry, we first quantified the composition of the different memory and pro-inflammatory immune subpopulations in samples of 58 patients with BD and compared them to 113 healthy controls. Second, to assess if cytomegalovirus infection was related to the resulted immune subpopulation compositions in the two groups, we measured cytomegalovirus-specific antibodies in serum. Thirdly, we assessed differences between the two groups in the serum levels of the immune cell differentiation factor interleukin-7. Compared to healthy controls, patients showed significantly higher T helper-17, T regulatory and T central memory cells (CD4+ and CD8+). Besides, patients showed significantly lower CD4+ T effector memory and CD4+ T effector memory re-expressing RA cells. Cytomegalovirus infection was not related to the observed abnormalities, with the exception of T helper-17 cells. This immune subpopulation was significantly higher only in patients seropositive to cytomegalovirus infection. Finally, interleukin-7 levels were significantly lower in BD compared to healthy controls. In conclusion, the aberrant levels of T memory cell populations in BD may suggest a T cell differentiation abnormality. The role of interleukin-7 in this putative abnormality should be further investigated.</p
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