3,232 research outputs found
The absolute positive partial transpose property for random induced states
In this paper, we first obtain an algebraic formula for the moments of a
centered Wishart matrix, and apply it to obtain new convergence results in the
large dimension limit when both parameters of the distribution tend to infinity
at different speeds. We use this result to investigate APPT (absolute positive
partial transpose) quantum states. We show that the threshold for a bipartite
random induced state on \C^d=\C^{d_1} \otimes \C^{d_2}, obtained by partial
tracing a random pure state on \C^d \otimes \C^s, being APPT occurs if the
environmental dimension is of order .
That is, when , such a random induced state is APPT with large
probability, while such a random states is not APPT with large probability when
. Besides, we compute effectively and and show that it is
possible to replace them by the same sharp transition constant when .Comment: 22 pages, 1 figur
Full waveform analysis for long-range 3D imaging laser radar
The new generation of 3D imaging systems based on laser radar (ladar) offers significant advantages in defense and security applications. In particular, it is possible to retrieve 3D shape information directly from the scene and separate a target from background or foreground clutter by extracting a narrow depth range from the field of view by range gating, either in the sensor or by postprocessing. We discuss and demonstrate the applicability of full-waveform ladar to produce multilayer 3D imagery, in which each pixel produces a complex temporal response that describes the scene structure. Such complexity caused by multiple and distributed reflection arises in many relevant scenarios, for example in viewing partially occluded targets, through semitransparent materials (e.g., windows) and through distributed reflective media such as foliage. We demonstrate our methodology on 3D image data acquired by a scanning time-of-flight system, developed in our own laboratories, which uses the time-correlated single-photon counting technique
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Correction: Selective particle and cell capture in a continuous flow using micro-vortex acoustic streaming
The authors regret that a citation to a relevant paper was missed. The following sentence and reference (ref. 1 shown below) should be added in the Introduction after the sentence ending "...of the applied flow rate.5,37": "For example, Lee et al. acoustically oscillate air/liquid interfaces using a âŒ50 kHz piezoelectric transducer to produce acoustic streaming fields for size-based separation of cells and particles".1 The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers
Correlated alterations in genome organization, histone methylation, and DNA-lamin A/C interactions in Hutchinson-Gilford progeria syndrome
Hutchinson-Gilford progeria syndrome (HGPS) is a premature aging disease that is frequently caused by a de novo point mutation at position 1824 in LMNA. This mutation activates a cryptic splice donor site in exon 11, and leads to an in-frame deletion within the prelamin A mRNA and the production of a dominant negative lamin A protein, known as progerin. Here we show that primary HGPS skin fibroblasts experience genome-wide correlated alterations in patterns of H3K27me3 deposition, DNA-lamin A/C associations, and, at late passages, genome-wide loss of spatial compartmentalization of active and inactive chromatin domains. We further demonstrate that the H3K27me3 changes associate with gene expression alterations in HGPS cells. Our results support a model that the accumulation of progerin in the nuclear lamina leads to altered H3K27me3 marks in heterochromatin, possibly through the down-regulation of EZH2, and disrupts heterochromatin-lamina interactions. These changes may result in transcriptional misregulation and eventually trigger the global loss of spatial chromatin compartmentalization in late passage HGPS fibroblasts
FEWZ 2.0: A code for hadronic Z production at next-to-next-to-leading order
We introduce an improved version of the simulation code FEWZ (Fully Exclusive
W and Z Production) for hadron collider production of lepton pairs through the
Drell-Yan process at next-to-next-to-leading-order (NNLO) in the strong
coupling constant. The program is fully differential in the phase space of
leptons and additional hadronic radiation. The new version offers users
significantly more options for customization. FEWZ now bins multiple,
user-selectable histograms during a single run, and produces parton
distribution function (PDF) errors automatically. It also features a
signifcantly improved integration routine, and can take advantage of multiple
processor cores locally or on the Condor distributed computing system. We
illustrate the new features of FEWZ by presenting numerous phenomenological
results for LHC physics. We compare NNLO QCD with initial ATLAS and CMS
results, and discuss in detail the effects of detector acceptance on the
measurement of angular quantities associated with Z-boson production. We
address the issue of technical precision in the presence of severe phase-space
cuts.Comment: 29 pages, 13 figure
A phase IV randomised, open-label pilot study to evaluate switching from protease-inhibitor based regimen to Bictegravir/Emtricitabine/Tenofovir Alafenamide single tablet regimen in Integrase inhibitor-naĂŻve, virologically suppressed HIV-1 infected adults harbouring drug resistance mutations (PIBIK study): study protocol for a randomised trial
Background
Currently recommended boosted protease-inhibitor (bPI) regimens may be associated with increased risk of cardiovascular or chronic kidney diseases; in addition, boosted regimens are particularly associated with drug-drug interactions. Since both cardiovascular and renal disease, and polypharmacy, are common in ageing people with HIV, there is a need for alternative efficacious regimens. bPI-based regimens are often the treatment of choice for individuals with pre-treatment or treatment-acquired resistance but it is plausible that carefully selected HIV-positive individuals with drug resistance, who are virologically suppressed on their current bPI regimen, could maintain virological efficacy when switched to bictegravir, emtricitabine and tenofovir alafenamide (B/F/TAF) fixed dose combination (FDC).
Methods/design
A phase IV, investigator-initiated, multicentre, open label pilot, randomised two-arm study to assess the safety and efficacy of switching from bPI regimen to B/F/TAF single tablet regimen in integrase inhibitor-naĂŻve, virologically suppressed adults with HIV-1 infection harbouring drug resistance mutations. Eligible individuals will either continue on their bPI regimen or switch to B/F/TAF FDC. After 24âweeks, all participants in the bPI arm will be switched to B/F/TAF and followed for a further 24âweeks and all participants will be followed for 48âweeks. The primary efficacy endpoint is the proportion of participants with HIV-1 RNA <â50 copies/mL at week 24 using pure virologic response whilst the secondary efficacy endpoint is the proportion of participants with HIV-1 RNA <â50 copies/mL at Week 48. Other secondary outcome measures include between arm comparisons of drug resistance at virological failure, safety and tolerability and patient-reported outcome measures.
Discussion
We aim to provide preliminary evidence of the efficacy of switching to B/F/TAF in patients with virological suppression on a bPI-based regimen who harbour select drug resistance mutations
Structure design and assessment of a floating foundation for offshore wind turbines
This paper summarizes the assessment of the structural analysis and design of a floating foundation for offshore floating wind turbine (FWT) based on DNVGL standard and Eurocode in terms of economy and reliability. The wind loads are calculated using empirical equations. The wave loads are obtained and verified using various methods including hand calculation, AQWA and Flow-3D. It is found that the shell thickness could be reduced significantly by introducing the stiffeners (stringer or ring), which can decrease the weight of the hull and lower the cost. While DNVGL and Eurocode yield similar design solutions if using plane shell structures, Eurocode significantly underestimates the buckling resistance of stiffened cylindrical shells
Acute rejection is associated with antibodies to non-Gal antigens in baboons using Gal-knockout pig kidneys
We transplanted kidneys from α1,3-galactosyltransferase knockout (GalT-KO) pigs into six baboons using two different immunosuppressive regimens, but most of the baboons died from severe acute humoral xenograft rejection. Circulating induced antibodies to non-Gal antigens were markedly elevated at rejection, which mediated strong complement-dependent cytotoxicity against GalT-KO porcine target cells. These data suggest that antibodies to non-Gal antigens will present an additional barrier to transplantation of organs from GalT-KO pigs to humans. © 2005 Nature Publishing Group
Transverse Momentum Dependent Parton Distribution/Fragmentation Functions at an Electron-Ion Collider
We present a summary of a recent workshop held at Duke University on Partonic
Transverse Momentum in Hadrons: Quark Spin-Orbit Correlations and Quark-Gluon
Interactions. The transverse momentum dependent parton distribution functions
(TMDs), parton-to-hadron fragmentation functions, and multi-parton correlation
functions, were discussed extensively at the Duke workshop. In this paper, we
summarize first the theoretical issues concerning the study of partonic
structure of hadrons at a future electron-ion collider (EIC) with emphasis on
the TMDs. We then present simulation results on experimental studies of TMDs
through measurements of single spin asymmetries (SSA) from semi-inclusive
deep-inelastic scattering (SIDIS) processes with an EIC, and discuss the
requirement of the detector for SIDIS measurements. The dynamics of parton
correlations in the nucleon is further explored via a study of SSA in D (`D)
production at large transverse momenta with the aim of accessing the unexplored
tri-gluon correlation functions. The workshop participants identified the SSA
measurements in SIDIS as a golden program to study TMDs in both the sea and
valence quark regions and to study the role of gluons, with the Sivers
asymmetry measurements as examples. Such measurements will lead to major
advancement in our understanding of TMDs in the valence quark region, and more
importantly also allow for the investigation of TMDs in the sea quark region
along with a study of their evolution.Comment: 44 pages 23 figures, summary of Duke EIC workshop on TMDs accepted by
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