2,649 research outputs found
Towards a new critical edition of the scholia to the Iliad: a specimen
An on-going new critical edition is presented, designed to gather together for the first time all the scholia vetera to the Iliad transmitted by the manuscript tradition. A short introduction is followed by a sample of the new critical text (i.e. sch. in Iliadem A 6-11), compared to the corresponding part in Hartmut Erbse's edition
Mitral valve repair in heart failure
Mitral regurgitation (MR) is a frequent complication of endâstage heart failure. Historically, these patients were either managed medically or with mitral valve replacement, both associated with poor outcomes. Mitral valve repair via an âundersizedâ annuloplasty repair is safe and effectively corrects MR in heartâfailure patients. All of the observed changes contribute to reverse remodeling and restoration of the normal leftâventricular geometric relationship. Mitral valve repair offers a new strategy for patients with MR and endâstage heart failure.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/102643/1/ejhf00125-2.pd
Probing the scalar potential via double Higgs boson production at hadron colliders
We present a sensitivity study on the cubic and quartic self couplings in double Higgs production via gluon fusion at hadron colliders. Considering the relevant operators in the Standard Model Effective Field Theory up to dimension eight, we calculate the dominant contributions up to two-loop level, where the first dependence on the quartic interaction appears. Our approach allows to study the independent variations of the two self couplings and to clearly identify the terms necessary to satisfy gauge invariance and to obtain UV-finite results order by order in perturbation theory. We focus on the bbÂŻ γγ signature for simplicity and provide the expected bounds for the cubic and quartic self couplings at the 14 TeV LHC with 3000 fb â1 (HL-LHC) and for a future 100 TeV collider (FCC-100) with 30 ab â1 . We find that while the HL-LHC will provide very limited sensitivity on the quartic self coupling, precision measurements of double Higgs production at a FCC-100 will offer the opportunity to set competitive bounds. We show that combining information from double and triple Higgs production leads to significantly improved prospects for the determination of the quartic self coupling
West Asian sources of the Eurasian component in Ethiopians: a reassessment
The presence of genomic signatures of Eurasian origin in contemporary Ethiopians has been reported by several authors and estimated to have arrived in the area from 3000 years ago. Several studies reported plausible source populations for such a signature, using haplotype based methods on modern data or single-site methods on modern or ancient data. These studies did not reach a consensus and suggested an Anatolian or Sardinia-like proxy, broadly Levantine or Neolithic Levantine as possible sources. We demonstrate, however, that the deeply divergent, autochthonous African component which accounts for ~50% of most contemporary Ethiopian genomes, affects the overall allele frequency spectrum to an extent that makes it hard to control for it and, at once, to discern between subtly different, yet important, Eurasian sources (such as Anatolian or Levant Neolithic ones). Here we re-assess pattern of allele sharing between the Eurasian component of Ethiopians (here called âNAFâ for Non African) and ancient and modern proxies. Our results unveil a genomic legacy that may connect the Eurasian genetic component of contemporary Ethiopians with Sea People and with population movements that affected the Mediterranean area and the Levant after the fall of the Minoan civilization
Optonongenetic enhancement of activity in primary cortical neurons
It has been recently demonstrated that the exposure of naive neuronal cells to lightâat the basis of optogenetic techniques and calcium imaging measurementsâmay alter neuronal firing. Indeed, understanding the effect of light on nongenetically modified neurons is crucial for a correct interpretation of calcium imaging and optogenetic experiments. Here we investigated the effect of continuous visible LED light exposure (490 nm, 0.18â1.3 mW/mm2) on spontaneous activity of primary neuronal networks derived from the early postnatal mouse cortex. We demonstrated, by calcium imaging and patch clamp experiments, that illumination higher than 1.0 mW/mm2 causes an enhancement of network activity in cortical cultures. We investigated the possible origin of the phenomena by blocking the transient receptor potential vanilloid 4 (TRPV4) channel, demonstrating a complex connection between this temperature-dependent channel and the measured effect. The results presented here shed light on an exogenous artifact, potentially present in all calcium imaging experiments, that should be taken into account in the analysis of fluorescence data
Assessment of White Matter Tract Damage in Patients with Amyotrophic Lateral Sclerosis: A Diffusion Tensor MR Imaging Tractography Study
BACKGROUND AND PURPOSE: Most DTI studies in ALS have been limited to the assessment of the CST damage. In this study, we used DTI tractography to investigate whether microstructural abnormalities occur in the major motor and extramotor WM tracts in mildly disabled patients with ALS. MATERIALS AND METHODS: Brain conventional MR imaging and DTI were performed in 24 patients with probable or definite ALS and mild disability (ALSFRS score, â„20) and 20 healthy controls. The mean disease progression rate was 0.62 (range = 0.08â2.50). DTI tractography was used to segment the CST, the corpus callosum, and the major WM association tracts (ie, cingulum, uncinate fasciculus, inferior fronto-occipital, inferior longitudinal, and superior longitudinal fasciculi). RESULTS: Compared with healthy controls, patients with ALS showed significantly decreased FA and significantly increased MD and radial D of the CST bilaterally (P values from .005 to .01). Patients with ALS also had a significantly increased axial D of the right uncinate fasciculus relative to controls (P = .04). CST FA significantly correlated with the rate of disease progression (right CST: r = â0.50, P = .02; left CST: r = â0.41, P = .05). CONCLUSIONS: Patients with ALS and mild disability have preferential damage to the CST. The association of CST damage with the rate of disease progression suggests that DTI has the potential to provide in vivo markers of ALS evolution. The subtle involvement of the uncinate fasciculus may precede the appearance of behavioral symptoms in patients with ALS
Service Orientation and the Smart Grid state and trends
The energy market is undergoing major changes, the most notable of which is the transition from a hierarchical closed system toward a more open one highly based on a âsmartâ information-rich infrastructure. This transition calls for new information and communication technologies infrastructures and standards to support it. In this paper, we review the current state of affairs and the actual technologies with respect to such transition. Additionally, we highlight the contact points between the needs of the future grid and the advantages brought by service-oriented architectures.
N_2H^+ and N^(15)NH^+ toward the prestellar core 16293E in L1689N
Context. Understanding the processes that could lead to an enrichment of molecules in ^(15)N atoms is of particular interest because this may shed light on the relatively strong variations observed in the ^(14)N/^(15)N ratio in various solar system environments.
Aims. The sample of molecular clouds where ^(14)N/^(15)N ratios have been measured currently is small and has to be enlarged to allow statistically significant studies. In particular, the N_2H^+ molecule currently shows the broadest spread of ^(14)N/^(15)N ratios in high-mass star-forming regions. However, the ^(14)N/^(15)N ratio in N_2H^+ was obtained in only two low-mass star-forming regions (L1544 and B1b). We here extend this sample to a third dark cloud.
Methods. We targeted the 16293E prestellar core, where the N^(15)NH^+J = 1â0 line was detected. Using a model previously developed for the physical structure of the source, we solved the molecular excitation with a nonlocal radiative transfer code. For this purpose, we computed specific collisional rate coefficients for the N^(15)NH^+-H_2 collisional system. As a first step of the analysis, the N_2H^+ abundance profile was constrained by reproducing the N_2H^+J = 1â0 and 3â2 maps. A scaling factor was then applied to this profile to match the N^(15)NH^+J = 1â0 spectrum.
Results. We derive a column density ratio N_2H^+/N^(15)NH^+ = 330^(+170)_(-100).
Conclusions. We performed a detailed analysis of the excitation of N_2H^+ and N^(15)NH^+ in the direction of the 16293E core with modern models that solve the radiative transfer and with the most accurate collisional rate coefficients available to date. We obtained the third estimate of the N_2H^+/N^(15)NH^+ column density ratio in the direction of a cold prestellar core. The current estimate ~330 agrees with the typical value of the elemental isotopic ratio in the local interstellar medium. It is lower than in some other cores, however, where values as high as 1300 have been reported
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