72 research outputs found
Acoustic response of a rigid frame porous medium slab with a periodic set of inclusions
The acoustic response of a rigid frame porous slab with a periodic set of
inclusions is calculated by use of a multipole method. The acoustic properties,
in particular the absorption, of such a structure are then derived and studied.
Numerical results together with a modal analysis show that the addition of a
periodic set of high-contrast inclusions leads to quasi-modes excitation of
both the slab and the gratings, and to a large increase of the acoustic
absorption of the initial slab, this being partly due to the quasi-modes
excitation.Comment: submitted to Journal of Sound and Vibratio
Lower bounds rule!
We propose two axioms that introduce lower bounds into resource monotonicity requirements for rules for the problem of adjudicating conflicting claims. Suppose the amount to divide increases. The first axiom requires that two claimants whose lower bound changes equally experience an equal change in awards. The second axiom requires that extra resources are divided only among those claimants who experience a strictly positive change in their lower bound. We show that, in the two-claimant case, Concede-and-Divide is the only rule that satisfies both axioms when the axioms are defined over a large set of lower bounds that include the minimal rights lower bound and the secured lower bound. We also show that, in the n-claimant case where at least one claimant claims the total amount, the Minimal Overlap rule is the only rule that satisfies both axioms when the axioms are defined over the secured lower bound.claims problems, lower bounds, concede-and-divide, minimal overlap rule
The digital readout system for the CMS electromagnetic calorimeter
The CMS Electromagnetic Calorimeter is a high-precision detector demanding innovative solutions in order to cope with the high dynamic range and the extreme high resolution of the detector as well as with the harsh environment created by the high level of radiation and the 4 T magnetic field. The readout system is partly placed within the detector and partly in the adjacent counting room. As the on-detector electronics must cope with the harsh environment the use of standard components is excluded for this part of the system. This paper describes the solutions adopted for the high-precision analogue stages, the A-D conversion, the optical transfer of the raw data from the on-detector part to the so-called Upper Level Readout, placed in the counting room, and the functionality of the latter. The ECAL is instrumental in providing information to the first-level trigger process and the generation of this information will be described. Also, the problem of reducing the raw data volume (6*10/sup 12/ bytes /s) to a level that can be handled by the central DAQ system (10/sup 5/ bytes/s) without degrading the physics performance will be discussed. (3 refs)
Preoperative FDG-PET/CT Is an Important Tool in the Management of Patients with Thick (T4) Melanoma
The yield of preoperative PET/CT (PET/CT) for regional and distant metastases for thin/intermediate thickness melanoma is low. Objective of this study is to determine if PET/CT performed for T4 melanomas helps guide management and alter treatment plans. Methods. Retrospective cohort of 216 patients with T4 melanomas treated at two tertiary institutions. Fifty-six patients met our inclusion criteria (T4 lesion, PET/CT and no clinical evidence of metastatic disease). Results. Fifty-six patients (M: 32, F: 24) with median tumor thickness of 6 mm were identified. PET/CT recognized twelve with regional and four patients with metastatic disease. Melanoma-related treatment plan was altered in 11% of the cases based on PET/CT findings. PET/CT was negative 60% of the time, in 35% of the cases; it identified incidental findings that required further evaluation. Conclusion. Patients with T4 lesions, PET/CT changed the treatment plan 18% of the time. Regional findings changed the surgical treatment plan in 11% and the adjuvant plan in 7% of our cases due to the finding of metastatic disease. Additionally 20 patients had incidental findings that required further workup. In this subset of patients, we feel there is a benefit to PET/CT, and further studies should be performed to validate our findings
Comparison of chemical compounds associated with sclerites from healthy and diseased sea fan corals (Gorgonia ventalina)
© The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PeerJ 5 (2017): e3677, doi:10.7717/peerj.3677.The roles of gorgonian sclerites as structural components and predator deterrents have been widely studied. Yet their role as barriers against microbes has only recently been investigated, and even less is known about the diversity and roles of the chemical compounds associated with sclerites. Here, we examine the semi-volatile organic compound fraction (SVOCs) associated with sclerites from healthy and diseased Gorgonia ventalina sea fan corals to understand their possible role as a stress response or in defense of infection. We also measured the oxidative potential of compounds from diseased and healthy G. ventalina colonies.
The results showed that sclerites harbor a great diversity of SVOCs. Overall, 70 compounds were identified, the majority of which are novel with unknown biological roles. The majority of SVOCs identified exhibit multiple immune-related roles including antimicrobial and radical scavenging functions. The free radical activity assays further confirmed the anti-oxidative potential of some these compounds. The anti-oxidative activity was, nonetheless, similar across sclerites regardless of the health condition of the colony, although sclerites from diseased sea fans display slightly higher anti-oxidative activity than the healthy ones.
Sclerites harbor great SVOCs diversity, the majority of which are novel to sea fans or any other corals. Yet the scientific literature consulted showed that the roles of compounds found in sclerites vary from antioxidant to antimicrobial compounds. However, this study fell short in determine the origin of the SVOCs identified, undermining our capacity to determine the biological roles of the SVOCs on sclerites and sea fans.This work was supported by the Puerto Rico Center for Environmental Neuroscience (PRCEN) through an NSF Centers of Research Excellent in Science and Technology (CREST) award, number HRD-1137725
Table S1: List of semivolatile organic compounds (SVOCs) isolated from sclerites from: healthy fans (HH), from healthy tissue from diseased fans (HD) and diseased tissue (DD) and their respective roles.
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