•Mini-RF on LRO collected bistatic S-band radar data of the lunar nearside from 2012 to 2015 to observe the scattering characteristics of the upper meter(s) of the lunar regolith.•An opposition ...effect was observed for the ejecta blankets of two Copernican-aged craters and for the floor of the south-polar crater Cabeus.•The unique response of Cabeus floor materials may indicate the presence of water ice.
The Miniature Radio Frequency (Mini-RF) instrument aboard NASA's Lunar Reconnaissance Orbiter (LRO) is a hybrid dual-polarized synthetic aperture radar (SAR) that operated in concert with the Arecibo Observatory to collect bistatic radar data of the lunar nearside from 2012 to 2015. The purpose of this bistatic campaign was to characterize the radar scattering properties of the surface and near-surface, as a function of bistatic angle, for a variety of lunar terrains and search for a coherent backscatter opposition effect indicative of the presence of water ice. A variety of lunar terrain types were sampled over a range of incidence and bistatic angles; including mare, highland, pyroclastic, crater ejecta, and crater floor materials. Responses consistent with an opposition effect were observed for the ejecta of several Copernican-aged craters and the floor of the south-polar crater Cabeus. The responses of ejecta material varied by crater in a manner that suggests a relationship with crater age. The response for Cabeus was observed within the portion of its floor that is not in permanent shadow. The character of the response differs from that of crater ejecta and appears unique with respect to all other lunar terrains observed. Analysis of data for this region suggests that the unique nature of the response may indicate the presence of near-surface deposits of water ice.
The present study examined whether excitotoxic lesions of the perirhinal cortex can affect acquisition of a place-object conditional task in which object and spatial information must be integrated. ...Testing was carried out in a double
Y
-maze apparatus, in which rats learned a conditional rule of the type, "In Place X, choose Object A, not Object B (A+ vs. B−); in Place Y, choose Object B, not Object A (A− vs. B+)." Perirhinal cortex lesions significantly impaired acquisition of this task while sparing performance of an allocentric spatial memory task performed in a radial arm maze. Perirhinal cortex lesions also had no apparent effect on a 1-pair object discrimination task performed in the double
Y
maze or on retention and acquisition of 4-pair concurrent discrimination problems performed in a computer-automated touch screen testing apparatus. The results suggest that, although the perirhinal cortex and hippocampus can be functionally dissociated, their normal mode of operation includes the integration of object and spatial information.
We have used the Kaguya laser altimeter-derived topography to conduct a comprehensive study of the illumination conditions at the Moon’s south pole. We have determined, by comparing simulated and ...actual Clementine images, that the Kaguya topography can be used to generate realistic illumination conditions. We generated an average illumination map for the year 2020 for the lunar south pole region. From this we identified the areas that receive the most illumination. The place receiving the most illumination (86% of the year) is located close to the rim of Shackleton crater at 88.74°S 124.5°E. However two other areas, less than 10
km apart from each other, are collectively lit for 94% of the year. We found that sites exist near the south pole that are continuously lit for several months during summer. We were also able to map the locations and durations of eclipse periods for these areas. Finally we analyzed the seasonal variations in lighting conditions, from summer to winter, for key areas near the south pole. We conclude that areas exist near the south pole that have illumination conditions that make them ideal candidates as future outpost sites.
The azimuthal correlation angle, \(\Delta\phi\), between the scattered lepton and the leading jet in deep inelastic \(e^{\pm}p\) scattering at HERA has been studied using data collected with the ZEUS ...detector at a centre-of-mass energy of \(\sqrt{s} = 318 \;\mathrm{GeV}\), corresponding to an integrated luminosity of \(326 \;\mathrm{pb}^{-1}\). A measurement of jet cross sections in the laboratory frame was made in a fiducial region corresponding to photon virtuality \(10 \;\mathrm{GeV}^2 < Q^2 < 350 \;\mathrm{GeV}^2\), inelasticity \(0.04 < y < 0.7\), outgoing lepton energy \(E_e > 10 \;\mathrm{GeV}\), lepton polar angle \(140^\circ < \theta_e < 180^\circ\), jet transverse momentum \(2.5 \;\mathrm{GeV} < p_\mathrm{T,jet} < 30 \;\mathrm{GeV}\), and jet pseudorapidity \(-1.5 < \eta_\mathrm{jet} < 1.8\). Jets were reconstructed using the \(k_\mathrm{T}\) algorithm with the radius parameter \(R = 1\). The leading jet in an event is defined as the jet that carries the highest \(p_\mathrm{T,jet}\). Differential cross sections, \(d\sigma/d\Delta\phi\), were measured as a function of the azimuthal correlation angle in various ranges of leading-jet transverse momentum, photon virtuality and jet multiplicity. Perturbative calculations at \(\mathcal{O}(\alpha_{s}^2)\) accuracy successfully describe the data within the fiducial region, although a lower level of agreement is observed near \(\Delta\phi \rightarrow \pi\) for events with high jet multiplicity, due to limitations of the perturbative approach in describing soft phenomena in QCD. The data are equally well described by Monte Carlo predictions that supplement leading-order matrix elements with parton showering.
Understanding the mechanisms that drive HIV expression and latency is a key goal for achieving an HIV cure. Here we investigate the role of the SETD2 histone methyltransferase, which deposits H3K36 ...trimethylation (H3K36me3), in HIV infection. We show that prevention of H3K36me3 by a potent and selective inhibitor of SETD2 (EPZ-719) leads to reduced post-integration viral gene expression and accelerated emergence of latently infected cells. CRISPR/Cas9-mediated knockout of SETD2 in primary CD4 T cells confirmed the role of SETD2 in HIV expression. Transcriptomic profiling of EPZ-719-exposed HIV-infected cells identified numerous pathways impacted by EPZ-719. Notably, depletion of H3K36me3 prior to infection did not prevent HIV integration but resulted in a shift of integration sites from highly transcribed genes to quiescent chromatin regions and to polycomb repressed regions. We also observed that SETD2 inhibition did not apparently affect HIV RNA levels, indicating a post-transcriptional mechanism affecting HIV expression. Viral RNA splicing was modestly reduced in the presence of EPZ-719. Intriguingly, EPZ-719 exposure enhanced responsiveness of latent HIV to the HDAC inhibitor vorinostat, suggesting that H3K36me3 can contribute to a repressive chromatin state at the HIV locus. These results identify SETD2 and H3K36me3 as novel regulators of HIV integration, expression and latency.
A
bstract
The photoproduction of
D
∗±
mesons has been measured with the ZEUS detector at HERA at three different
ep
centre-of-mass energies,
s
, of 318, 251 and 225 GeV. For each data set,
D
∗±
...mesons were required to have transverse momentum,
p
T
D
∗
, and pseudo-rapidity,
η
D
∗
, in the ranges 1
.
9
< p
T
D
∗
<
20 GeV and |
η
D
∗
|
<
1
.
6. The events were required to have a virtuality of the incoming photon,
Q
2
, of less than 1 GeV
2
. The dependence on
s
was studied by normalising to the high-statistics measurement at
s
=
318
GeV. This led to the cancellation of a number of systematic effects both in data and theory. Predictions from next-to-leading-order QCD describe the
s
dependence of the data well.
Measurements of hadronic final states by H1 and ZEUS at HERA are presented. The H1 measurements consist of measurements of charged particle spectra in deep -inelastic \(ep\) scattering and of forward ...photons and neutrons. The ZEUS results consist of a series of measurements of prompt photons in photoproduction.
Genetic Landscape of a Cell Costanzo, Michael; Baryshnikova, Anastasia; Bellay, Jeremy ...
Science (American Association for the Advancement of Science),
01/2010, Letnik:
327, Številka:
5964
Journal Article
Recenzirano
Odprti dostop
A genome-scale genetic interaction map was constructed by examining 5.4 million gene-gene pairs for synthetic genetic interactions, generating quantitative genetic interaction profiles for ...approximately 75% of all genes in the budding yeast, Saccharomyces cerevisiae. A network based on genetic interaction profiles reveals a functional map of the cell in which genes of similar biological processes cluster together in coherent subsets, and highly correlated profiles delineate specific pathways to define gene function. The global network identifies functional cross-connections between all bioprocesses, mapping a cellular wiring diagram of pleiotropy. Genetic interaction degree correlated with a number of different gene attributes, which may be informative about genetic network hubs in other organisms. We also demonstrate that extensive and unbiased mapping of the genetic landscape provides a key for interpretation of chemical-genetic interactions and drug target identification.
A new measurement of inclusive-jet cross sections in the Breit frame in neutral current deep inelastic scattering using the ZEUS detector at the HERA collider is presented. The data were taken in the ...years 2004 to 2007 at a centre-of-mass energy of \(318\,\text{GeV}\) and correspond to an integrated luminosity of \(347\,\text{pb}^{-1}\). Massless jets, reconstructed using the \(k_t\)-algorithm in the Breit reference frame, have been measured as a function of the squared momentum transfer, \(Q^2\), and the transverse momentum of the jets in the Breit frame, \(p_{\perp,\text{Breit}}\). The measured jet cross sections are compared to previous measurements and to perturbative QCD predictions. The measurement has been used in a next-to-next-to-leading-order QCD analysis to perform a simultaneous determination of parton distribution functions of the proton and the strong coupling, resulting in a value of \(\alpha_s(M_Z^2) = 0.1142 \pm 0.0017~\text{(experimental/fit)}\) \({}^{+0.0006}_{-0.0007}~\text{(model/parameterisation)}\) \({}^{+0.0006}_{-0.0004}~\text{(scale)}\), whose accuracy is improved compared to similar measurements. In addition, the running of the strong coupling is demonstrated using data obtained at different scales.
Malondialdehyde-acetaldehyde adducts (MAA) have been implicated in atherosclerosis. The purpose of this study was to investigate the role of MAA in atherosclerotic disease. Serum samples from ...controls (n = 82) and patients with; non-obstructive coronary artery disease (CAD), (n = 40), acute myocardial infarction (AMI) (n = 42), or coronary artery bypass graft (CABG) surgery due to obstructive multi-vessel CAD (n = 72), were collected and tested for antibody isotypes to MAA-modifed human serum albumin (MAA-HSA). CAD patients had elevated relative levels of IgG and IgA anti-MAA, compared to control patients (p<0.001). AMI patients had a significantly increased relative levels of circulating IgG anti-MAA-HSA antibodies as compared to stable angina (p<0.03) or CABG patients (p<0.003). CABG patients had significantly increased relative levels of circulating IgA anti-MAA-HSA antibodies as compared to non-obstructive CAD (p<0.001) and AMI patients (p<0.001). Additionally, MAA-modified proteins were detected in the tissue of human AMI lesions. In conclusion, the IgM, IgG and IgA anti-MAA-HSA antibody isotypes are differentially and significantly associated with non-obstructive CAD, AMI, or obstructive multi-vessel CAD and may serve as biomarkers of atherosclerotic disease.
PDF
