Evaluation of a pulsed ultrasonic Doppler flowmeter

The in vivo application of the pulsed ultrasound Doppler velocity meter (PUDVM) for measuring arterial velocity waveforms is reported. In particular, the performance of the PUDVM is compared with a hot film anemometer of proven accuracy

SgpDec : Cascade (de)compositions of finite transformation semigroups and permutation groups

We describe how the SgpDec computer algebra package can be used for composing and decomposing permutation groups and transformation semigroups hierarchically by directly constructing substructures of wreath products, the so called cascade products.Final Accepted Versio

Photon signature analysis using template matching

We describe an approach to detect improvised explosive devices (IEDs) by using a template matching procedure. This approach relies on the signature due to backstreaming ? photons from various targets. In this work we have simulated cylindrical targets of aluminum, iron, copper, water and ammonium nitrate (nitrogen-rich fertilizer). We simulate 3.5 MeV source photons distributed on a plane inside a shielded area using Monte Carlo N-Particle (MCNP TM) code version 5 (V5). The 3.5 MeV source gamma rays yield 511 keV peaks due to pair production and scattered gamma rays. In this work, we simulate capture of those photons that backstream, after impinging on the target element, toward a NaI detector. The captured backstreamed photons are expected to produce a unique spectrum that will become part of a simple signal processing recognition system based on the template matching method. Different elements were simulated using different sets of random numbers in the Monte Carlo simulation. To date, the sum of absolute differences (SAD) method has been used to match the template. In the examples investigated, template matching was found to detect all elements correctly

Rigidity analysis of HIV-1 protease

We present a rigidity analysis on a large number of X-ray crystal structures of the enzyme HIV-1 protease using the 'pebble game' algorithm of the software FIRST. We find that although the rigidity profile remains similar across a comprehensive set of high resolution structures, the profile changes significantly in the presence of an inhibitor. Our study shows that the action of the inhibitors is to restrict the flexibility of the beta-hairpin flaps which allow access to the active site. The results are discussed in the context of full molecular dynamics simulations as well as data from NMR experiments.Comment: 4 pages, 3 figures. Conference proceedings for CMMP conference 2010 which was held at the University of Warwic

A comparison of cortical and trabecular bone from C57 Black 6 mice using Raman spectroscopy

Peer reviewedPostprin

First-Order Electroweak Phase Transition in the Standard Model with a Low Cutoff

We study the possibility of a first-order electroweak phase transition (EWPT) due to a dimension-six operator in the effective Higgs potential. In contrast with previous attempts to make the EWPT strongly first-order as required by electroweak baryogenesis, we do not rely on large one-loop thermally generated cubic Higgs interactions. Instead, we augment the Standard Model (SM) effective theory with a dimension-six Higgs operator. This addition enables a strong first-order phase transition to develop even with a Higgs boson mass well above the current direct limit of 114 GeV. The phi^6 term can be generated for instance by strong dynamics at the TeV scale or by integrating out heavy particles like an additional singlet scalar field. We discuss conditions to comply with electroweak precision constraints, and point out how future experimental measurements of the Higgs self couplings could test the idea.Comment: 5 pages, 4 figures. v2: corrected typos, improved discussion of the case lambda<0 and added references. To be published in PR

Yield-Per-Recruit Analysis for Black Drum, Pogonias cromis, Along the East Coast of the United States and Management Strategies for Chesapeake Bay

Black drum, Pogonias cromis along the U.S. East Coast is subject to commercial and recreational harvest. However, prior to this study no modeling had been undertaken to examine the potential for overfishing in the Chesapeake Bay region. We present evidence from yield-per-recruit models that growth overfishing of black drum is unlikely under current fishing practices in this region. Particular attention was given to fishing practices in the Chesapeake Bay region where old, large fish predominate in the commercial and recreational catches (mean age=26 years: mean total length=108.4 cm; mean weight 22.1 kg). Yield-per-recruit model results showed that growth overfishing was unlikely in the Chesapeake Bay region under all but the lowest estimates of natural mortality (M=0.02-0.04). Such extreme low values of M predict potential life span of 200 years and were dismissed as improbable-the oldest age recorded for this species is 59 years. Additionally, biomass-per-recruit model results indicated a 42-59% decrease to current biomass from the unfished stock. The apparent age-specific migration of this stock argues for protection of young fish that have dominated the catch in Northeast Florida. Modeling indicated that growth overfishing could result from heavy fishing on these young ages and would all but eliminate this resource of the northern fishery

Reproduction of Black Drum, Pogonias cromis, from the Chesapeake Bay Region

Ovaries of black drum, Pogonias cromis, collected from the Chesapeake Bay region in 1992, were used to describe reproductive strategy and fecundity. Histological examination showed that black drum spawn in the Chesapeake Bay region from April through early June. Distributions of oocyte diameter showed distinct oocyte-developmental groups indicating that Chesapeake Bay black drum are group-synchronous batch spawners. Female black drum are extremely fecund ranging from 414,000 to 3,736,000 hydrated oocytes (mean = 1,389,000) per batch with a spawning periodicity of 3.8 days. Estimates of spawning strategy, spawning periodicity, and batch fecundity for black drum from the Chesapeake Bay region were similar to reported estimates from the Gulf of Mexico

Blood pressure measurements in the ankle are not equivalent to blood pressure measurements in the arm

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