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The SH3 domain of p56lck binds to proline-rich sequences in the cytoplasmic domain of CD2.
CD2, a cell surface glycoprotein expressed on T cells and natural killer cells, can couple to signaling pathways that result in T cell proliferation. An Src-like protein tyrosine kinase, p56lck, coprecipitates with CD2, and perturbation of CD2 by monoclonal antibodies results in an increase in the activity of p56lck, suggesting that an interaction with p56lck contributes to CD2-mediated signaling. Herein, we investigate the mechanism by which CD2 associates with p56lck. We demonstrate that CD2 and p56lck associate when coexpressed in nonlymphoid cells, that this association requires the cytoplasmic domain of CD2, and that the SH3 domain of p56lck mediates its interactions with CD2. Using truncation mutants of CD2, we identify two regions in the cytoplasmic domain of CD2 involved in binding p56lck. Each region contains a proline-rich sequence that, in the form of a synthetic peptide, directly binds p56lck. Thus, proline-rich sequences in the cytoplasmic domain of CD2 allow this transmembrane receptor to bind to the SH3 domain of p56lck
Amorphous interface layer in thin graphite films grown on the carbon face of SiC
Cross-sectional transmission electron microscopy (TEM) is used to
characterize an amorphous layer observed at the interface in graphite and
graphene films grown via thermal decomposition of C-face 4H-SiC. The amorphous
layer does not to cover the entire interface, but uniform contiguous regions
span microns of cross-sectional interface. Annular dark field scanning
transmission electron microscopy (ADF-STEM) images and electron energy loss
spectroscopy (EELS) demonstrate that the amorphous layer is a carbon-rich
composition of Si/C. The amorphous layer is clearly observed in samples grown
at 1600{\deg}C for a range of growth pressures in argon, but not at
1500{\deg}C, suggesting a temperature-dependent formation mechanism
Earth-Space Link Attenuation Estimation via Ground Radar Kdp
A method of predicting attenuation on microwave Earth/spacecraft communication links, over wide areas and under various atmospheric conditions, has been developed. In the area around the ground station locations, a nearly horizontally aimed polarimetric S-band ground radar measures the specific differential phase (Kdp) along the Earth-space path. The specific attenuation along a path of interest is then computed by use of a theoretical model of the relationship between the measured S-band specific differential phase and the specific attenuation at the frequency to be used on the communication link. The model includes effects of rain, wet ice, and other forms of precipitation. The attenuation on the path of interest is then computed by integrating the specific attenuation over the length of the path. This method can be used to determine statistics of signal degradation on Earth/spacecraft communication links. It can also be used to obtain real-time estimates of attenuation along multiple Earth/spacecraft links that are parts of a communication network operating within the radar coverage area, thereby enabling better management of the network through appropriate dynamic routing along the best combination of links
Observation of quantum-Hall effect in gated epitaxial graphene grown on SiC (0001)
Epitaxial graphene films were formed on the Si-face of semi-insulating 4H-SiC
substrates by a high temperature sublimation process. A high-k gate stack on
epitaxial graphene is realized by inserting a fully oxidized nanometer thin
aluminum film as a seeding layer followed by an atomic-layer deposition
process. The electrical properties of epitaxial graphene films are sustained
after gate stack formation without significant degradation. At low
temperatures, the quantum-Hall effect in Hall resistance is observed along with
pronounced Shubnikov-de Hass oscillations in diagonal magneto-resistance of
gated epitaxial graphene on SiC (0001).Comment: 2 new references adde
The Effect of Management Function on Minimum Health Services for Maternal and Child In Kupang Regency Health Care
Background: Maternal and child health programs are one of the Ministry of Health's top priorities. Because of Indonesia's high maternal mortality rate (MMR), the government has made MMR reduction a priority program in health development. Many pregnant women have still not given birth in health facilities, and maternal and child mortality rates in NTT remain high. Over the past five years, Kupang Regency has been one of the top five contributors to maternal and child mortality in East Nusa Tenggara. Objective: To determine the effect of management functions on the minimum service standards for maternal and child health at the Kupang Regency health center. Methods and Design:This is a quantitative study that was conducted in the area of the Kupang Regency health office, with a total sample of 30, using a purposive sampling technique and analyzing the data using simple logistic regression and multiple logistic regression. Results: Bivariate analysis showed a relationship between POAC and minimum service standards for maternal and child health, namely Planning (p = 0.009; OR = 25), Organizing (p = 0.015; OR = 19), Actuating (p = 0.009; OR = 25), and Controlling (p = 0.013; OR = 14); and multivariate analysis revealed that the Planning and Actuating variables had an effect simultaneously (p = 0.047; OR = 11). Conclusion: The variables that have the most influence on the minimum service standards for maternal and child health at the Kupang Regency health centers are Planning and Actuating variables
Quantum-Hall plateau-plateau transition in top-gated epitaxial graphene grown on SiC (0001)
We investigate the low-temperature magneto-transport properties of monolayer
epitaxial graphene films formed on the Si-face of semi-insulating 4H-SiC
substrates by a high temperature sublimation process. A high-k top-gate on the
epitaxial graphene is realized by inserting a fully oxidized nanometer thin
aluminum film as a seeding layer, followed by an atomic layer deposition
process. At low temperatures, the devices demonstrate a strong field effect by
the top gate with an on/off ratio of ~7 and an electron mobility up to ~3250
cm^2/Vs. After the observation of the half-integer quantum Hall effect for
monolayer epitaxial graphene films, detailed magneto-transport measurements
have been carried out including varying densities, temperatures, magnetic
fields and currents. We study the width of the distinguishable quantum-Hall
plateau to plateau transition (Landau level index n=0 to n=1) as temperature
(T) and current are varied. For both gate voltage and magnetic field sweeps and
T>10 K the transition width goes as T^{-\kappa} with exponent \kappa ~0.42.
This universal scaling exponent agrees well with those found in III-V
heterojunctions with short range alloy disorders and in exfoliated graphene.Comment: accepted by Journal of Applied Physic
On the Existence of the Logarithmic Correction Term in Black Hole Entropy-Area Relation
In this paper we consider a model universe with large extra dimensions to
obtain a modified black hole entropy-area relation. We use the generalized
uncertainty principle to find a relation between the number of spacetime
dimensions and the presence or vanishing of logarithmic prefactor in the black
hole entropy-area relation. Our calculations are restricted to the
microcanonical ensembles and we show that in the modified entropy-area
relation, the microcanonical logarithmic prefactor appears only when spacetime
has an even number of dimensions.Comment: 9 Pages, No Figure
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