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The Emerging Role of Ten-Eleven Translocation 1 in Epigenetic Responses to Environmental Exposures.
Mounting evidence from epidemiological studies and animal models has linked exposures to environmental factors to changes in epigenetic markers, especially in DNA methylation. These epigenetic changes may lead to dysregulation of molecular processes and functions and mediate the impact of environmental exposures in complex diseases. However, detailed molecular events that result in epigenetic changes following exposures remain unclear. Here, we review the emerging evidence supporting a critical role of ten-eleven translocation 1 (TET1) in mediating these processes. Targeting TET1 and its associated pathways may have therapeutic potential in alleviating negative impacts of environmental exposures, preventing and treating exposure-related diseases
Dirac sea effects in scattering from nuclei
The ratio of to cross sections has been calculated
microscopically using a boson-exchange amplitude in which the and
mesons are dressed by the modifications of the Dirac sea in nuclear
matter. In spite of the fact that this dressing leads to a scaling of the
mesons effective mass in nuclear matter, the effect on the ratio is found
to be weak.Comment: 8 pages, LaTeX, 2 figures available upon request, LPTB-93-
Interactions between two adjacent convection rolls in turbulent Rayleigh-Benard convection
Rayleigh-B{\'e}nard convection experiments were done with two adjacent cubic
cells with a partial wall in between to force the generation of two interacting
convection rolls. Observed stable states include both counter-rotating and
co-rotating states. The stability of each of these states and their dynamics
were modeled by stochastic ordinary differential equations of motion in terms
of the orientation, amplitude, and mean temperature of each convection roll.
The form of the interaction terms is predicted based on an effective turbulent
diffusion of temperature between the adjacent rolls. Predictions are made for
stable fixed points of the co- and counter-rotating states. This suggests that
the same turbulent thermal diffusivity that describes macroscopically averaged
heat transport also controls the interactions between neighboring convection
rolls. The surprising stability of co-rotating states is due to the temperature
difference between the neighboring rolls becoming large enough that the heat
flux between the rolls stabilizes the temperature profile of aligned
co-rotating states. This temperature difference can be driven by heating the
plates of the two cells to different mean temperatures. This shifts the
orientations of the rolls of counter-rotating states in opposite directions,
and for large temperature differences only co-rotating states are stable
Spontaneous switching between co-rotating and counter-rotating states is also
observed. Switching to counter-rotating states occurs mainly due to cessation
(a significant weakening of a convection roll), which reduces damping on
changes in orientation, allowing the orientation to change rapidly due to
diffusive fluctuations. Switching to co-rotating states is mainly driven by
smaller diffusive fluctuations, which have a positive feedback that
destabilizes the counter-rotating state.Comment: 28 pages, 17 figure
Total reaction cross sections for neutron-nucleus scattering
Neutron total reaction cross sections at 45, 50, 55, 60, 65, and 75 MeV from
nuclei 12C, 28Si, 56Fe, 90Zr, and 208Pb have been measured and are compared
with (microscopic) optical model predictions. The optical potentials were
obtained in coordinate space by full folding effective nucleon-nucleon
interactions with realistic nuclear ground state density matrices. Good to
excellent agreement is found.Comment: 5 pages, 1 figure, RevTeX
New Insights into Dissipation in the Electron Layer During Magnetic Reconnection
Detailed comparisons are reported between laboratory observations of
electron-scale dissipation layers near a reconnecting X-line and direct
two-dimensional full-particle simulations. Many experimental features of the
electron layers, such as insensitivity to the ion mass, are reproduced by the
simulations; the layer thickness, however, is about 3-5 times larger than the
predictions. Consequently, the leading candidate 2D mechanism based on
collisionless electron nongyrotropic pressure is insufficient to explain the
observed reconnection rates. These results suggest that, in addition to the
residual collisions, 3D effects play an important role in electron-scale
dissipation during fast reconnection.Comment: 17 pages, 4 figure
Thrusting and exhumation of the southern Mongolian Plateau: Joint thermochronological constraints from the Langshan Mountains, western Inner Mongolia, China
The Mongolian Plateau has undergone multi-stage denudation since the Late Triassic, and the NE-trending Langshan Mountains in the southern margin of the Mongolian Plateau is crucial to unraveling the Meso-Cenozoic cooling and exhumation history of the Mongolian Plateau. The Langshan Mountains are dominated by Precambrian gneiss and PermianâMiddle Triassic granitic plutons crosscut by a set of NE-striking thrust faults. A joint thermochronological study was conducted on 31 granitic and gneissic samples along the HQ and CU transects across the Langshan Mountains and other two samples from the BQ in the north of the Langshan Mountains. Four biotite/muscovite and three K-feldspar 40Ar/39Ar plateau ages range from 205 ± 1 to 161 ± 1 and 167 ± 1 to 131 ± 1 Ma, respectively. Thirty-three apatite fission track (AFT) ages are between 184 ± 11 and 79 ± 4 Ma, with mean track lengths from 11.1 ± 1.8 to 13.1 ± 1.4 ÎŒm of mostly unimodal distributions. Thirty-one single-grain raw AHe ages are in a range of 134 ± 8 to 21 ± 1 Ma. The AFT ages decrease monotonously from NW to SE until thrust faults along the two transects, with an age-jump across thrust F35. Joint thermal history modelling shows a three-stage cooling history as a result of denudation, especially with spatial differentiation in the first stage. Relative slow cooling at c. 0.6â1.0 °C/Ma occurred in the BQ and the northern part of the HQ transect during 220â100 Ma and the northern part of the CU transect during 160â100 Ma, respectively, with an amount of c. 2â3 km denudation between 160 and 100 Ma, implying little movement along the thrusts F13 and F33. In the middle and southern parts of the HQ transect and the southern part of the CU transect, rapid cooling at c. 4.0â7.0 °C/Ma, with c. 6â9 km denudation during 170â130 or 160â100 Ma, respectively, is probably influenced by thrusting of F35, F38 and F42 and the resultant tilting. A combination of thrusting, tilting, and denudation led to the youngering trends towards thrusts in different parts. However, there was no significant denudation across the Langshan Mountains in the second stage from c. 100 or 80 Ma until the last stage of rapid denudation (c. 2 km) since 20â10 Ma, which is simultaneous with the rapid uplift of the northern part of the Tibetan Plateau at c. 15 Ma. A youngering trend of AFT ages from the inner to the peripherals of the Mongolian Plateau implies the outward propagation of the Mongolian Plateau since the Mesozoic
Mini-conference and related sessions on laboratory plasma astrophysics
This paper provides a summary of some major physics issues and future perspectives discussed in the Mini-Conference on Laboratory Plasma Astrophysics. This mini-conference, sponsored by the Topical Group on Plasma Astrophysics, was held as part of the American Physical Societyâs Division of Plasma Physics 2003 Annual Meeting (October 27â31, 2003). Also included are brief summaries of selected talks on the same topic presented at two invited paper sessions (including a tutorial) and two contributed focus oral sessions, which were organized in coordination with the mini-conference by the same organizers. © 2004 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70409/2/PHPAEN-11-5-2976-1.pd
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