510 research outputs found
Quantum confinement corrections to the capacitance of gated one-dimensional nanostructures
With the help of a multi-configurational Green's function approach we
simulate single-electron Coulomb charging effects in gated ultimately scaled
nanostructures which are beyond the scope of a selfconsistent mean-field
description. From the simulated Coulomb-blockade characteristics we derive
effective system capacitances and demonstrate how quantum confinement effects
give rise to corrections. Such deviations are crucial for the interpretation of
experimentally determined capacitances and the extraction of
application-relevant system parameters
Quantum kinetic description of Coulomb effects in one-dimensional nano-transistors
In this article, we combine the modified electrostatics of a one-dimensional
transistor structure with a quantum kinetic formulation of Coulomb interaction
and nonequilibrium transport. A multi-configurational self-consistent Green's
function approach is presented, accounting for fluctuating electron numbers. On
this basis we provide a theory for the simulation of electronic transport and
quantum charging effects in nano-transistors, such as gated carbon nanotube and
whisker devices and one-dimensional CMOS transistors. Single-electron charging
effects arise naturally as a consequence of the Coulomb repulsion within the
channel
The path of dishonesty: identification of mental processes with electrical neuroimaging.
Much research finds that lying takes longer than truth-telling. Yet, the source of this response time difference remains elusive. Here, we assessed the spatiotemporal evolution of electrical brain activity during honesty and dishonesty in 150 participants using a sophisticated electrical neuroimaging approach-the microstate approach. This uniquely positioned us to identify and contrast the entire chain of mental processes involved during honesty and dishonesty. Specifically, we find that the response time difference is the result of an additional late-occurring mental process, unique to dishonest decisions, interrupting the antecedent mental processing. We suggest that this process inhibits the activation of the truth, thus permitting the execution of the lie. These results advance our understanding of dishonesty and clarify existing theories about the role of increased cognitive load. More broadly, we demonstrate the vast potential of our approach to illuminate the temporal organization of mental processes involved in decision-making
Trichostatin A induced histone acetylation causes decondensation of interphase chromatin.
The effect of trichostatin A (TSA)-induced histone
acetylation on the interphase chromatin structure was
visualized in vivo with a HeLa cell line stably expressing
histone H2A, which was fused to enhanced yellow
fluorescent protein. The globally increased histone
acetylation caused a reversible decondensation of dense
chromatin regions and led to a more homogeneous
distribution. These structural changes were quantified by
image correlation spectroscopy and by spatially resolved
scaling analysis. The image analysis revealed that a
chromatin reorganization on a length scale from 200 nm to
>1 mm was induced consistent with the opening of
condensed chromatin domains containing several Mb of DNA. The observed conformation changes could be
assigned to the folding of chromatin during G1 phase by
characterizing the effect of TSA on cell cycle progression
and developing a protocol that allowed the identification of
G1 phase cells on microscope coverslips. An analysis by
flow cytometry showed that the addition of TSA led to a
significant arrest of cells in S phase and induced apoptosis.
The concentration dependence of both processes was
studied
МУЗЕЇ ДНІПРОПЕТРОВСЬКОЇ ОБЛАСТІ НА СУЧАСНОМУ ЕТАПІ
Розглянуто діяльність музеїв, участь їх у краєзнавчому русі, кількісні та якісні показники розвитку музейної галузі Дніпропетровської області на сучасному етапіAuthors have examined museum activities, their role in the movement of local lore, quantitative and qualitative indices of museum development in the Dniepropetrovsk region at present stage
Observation of 1D Behavior in Si Nanowires: Toward High-Performance TFETs
This article provides experimental evidence of one-dimensional behavior of silicon (Si) nanowires (NWs) at low-temperature through both transfer (Id−VG) and capaci- tance−voltage characteristics. For the first time, operation of Si NWs in the quantum capacitance limit (QCL) is experimentally demonstrated and quantitatively analyzed. This is of relevance since working in the QCL may allow, e.g., tunneling field-effect transistors (TFETs) to achieve higher on-state currents (Ion) and larger on-/off-state current ratios (Ion/Ioff), thus addressing one of the most severe limitations of TFETs. Comparison of the experimental data with simulations finds excellent agreement using a simple capacitor model
Tamoxifen-Independent Recombination in the RIP-CreER Mouse
The inducible Cre-lox system is a valuable tool to study gene function in a spatial and time restricted fashion in mouse models. This strategy relies on the limited background activity of the modified Cre recombinase (CreER) in the absence of its inducer, the competitive estrogen receptor ligand, tamoxifen. The RIP-CreER mouse (Tg (Ins2-cre/Esr1) 1Dam) is among the few available β-cell specific CreER mouse lines and thus it has been often used to manipulate gene expression in the insulin-producing cells of the endocrine pancreas
A Fully Tunable Single-Walled Carbon Nanotube Diode
We demonstrate a fully tunable diode structure utilizing a fully suspended
single-walled carbon nanotube (SWNT). The diode's turn-on voltage under forward
bias can be continuously tuned up to 4.3 V by controlling gate voltages, which
is ~6 times the nanotube bandgap energy. Furthermore, the same device design
can be configured into a backward diode by tuning the band-to-band tunneling
current with gate voltages. A nanotube backward diode is demonstrated for the
first time with nonlinearity exceeding the ideal diode. These results suggest
that a tunable nanotube diode can be a unique building block for developing
next generation programmable nanoelectronic logic and integrated circuits.Comment: 14 pages, 4 figure
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