Single-Base DNA Discrimination via Transverse Ionic Transport

We suggest to discriminate single DNA bases via transverse ionic transport, namely by detecting the ionic current that flows in a channel while a single-stranded DNA is driven through an intersecting nanochannel. Our all-atom molecular dynamics simulations indeed show that the ionic currents of the four bases are statistically distinct, thus offering another possible approach to sequence DNA.Comment: 5 pages, 3 figure

Clinical and Genetic Risk Factors Associated with Psoriatic Arthritis among Patients with Psoriasis.

IntroductionPsoriatic arthritis (PsA) is a chronic, inflammatory arthritis that affects an estimated 30% of patients with psoriasis. PsA is underdiagnosed in primary care and dermatology clinics due to a variety of reasons, including failure of healthcare providers to ask about symptoms, overlap of symptoms and signs with other rheumatologic conditions, and lack of a specific diagnostic test. A delay in PsA diagnosis and treatment, even as short as 6 months, can lead to decreased quality of life, increased joint damage, and worse long-term physical function. In this study, we sought to identify the clinical and genetic factors that help discriminate patients with PsA from those with cutaneous psoriasis only.MethodsWe analyzed a cohort of 974 psoriasis patients at an academic medical center, of whom 175 had confirmed PsA, and performed univariate, multivariate, and predictive modeling to determine factors associated with PsA.ResultsThe univariate analysis revealed significant positive associations of PsA with age, nail involvement, scalp involvement, skin fold involvement, elbow/knee involvement, psoriasis severity, plaque subtype, erythrodermic subtype, hypertension, type 2 diabetes, and coronary artery disease, and a significant negative association of PsA with the human leukocyte antigen (HLA)-C*06:02 allele. In the multivariate analysis, nail involvement, type 2 diabetes, and pustular psoriasis remained significantly associated with PsA, while HLA-C*06:02 positivity remained protective. There was a trend towards an association of PsA with older age, younger age of psoriasis onset, and skin fold involvement, while there was protective trend for smoking. A predictive model including both clinical and genetic factors showed reasonable discriminative ability between psoriasis and PsA, with an area under the curve of 0.87 for a receiver operating characteristic curve.ConclusionThis study identified a number of clinical and genetic features that could help stratify patients who are at higher risk for having PsA and for whom rheumatology referral may be beneficial

An ERP study of visual search showing early detection of feature conjunctions

An ERP study of visual search showing early detection of feature conjunction

On the Large N Limit of 3D and 4D Hermitian Matrix Models

The large N limit of the hermitian matrix model in three and four Euclidean space-time dimensions is studied with the help of the approximate Renormalization Group recursion formula. The planar graphs contributing to wave function, mass and coupling constant renormalization are identified and summed in this approximation. In four dimensions the model fails to have an interacting continuum limit, but in three dimensions there is a non trivial fixed point for the approximate RG relations. The critical exponents of the three dimensional model at this fixed point are $\nu = 0.665069$ and $\eta=0.19882$. The existence (or non existence) of the fixed point and the critical exponents display a fairly high degree of universality since they do not seem to depend on the specific (non universal) assumptions made in the approximation.Comment: Number 0.519689 in eqs (36) and (37) should be replaced by 0.303152. The critical exponents were computed with the correct number entry and are therefore UNCHANGE

eIDeCert: a user-centric solution for mobile identification

The necessity to certify one's identity for different purposes and the evolution of mobile technologies have led to the generation of electronic devices such as smart cards, and electronic identities designed to meet daily needs. Nevertheless, these mechanisms have a problem: they don't allow the user to set the scope of the information presented. That problem introduces interesting security and privacy challenges and requires the development of a new tool that supports user-centrity for the information being handled. This article presents eIDeCert, a tool for the management of electronic identities (eIDs) in a mobile environment with a user-centric approach. Taking advantage of existing eCert technology we will be able to solve a real problem. On the other hand, the application takes us to the boundary of what the technology can cope with: we will assess how close we are to the boundary, and we will present an idea of what the next step should be to enable us to reach the goal

Power corrections and perturbative coupling from lattice gauge thoeries

From the analysis of the perturbative expansion of the lattice regularized gluon condensate, toghether with MC data, we present evidence of OPE-unexpected dim-2 power corrections in the scaling behaviour of the Wilson loop. These can be interpreted as an indication that in lattice gauge theories the running coupling at large momentum contains contributions of order Q^2.Comment: 3 pages, 2 figures. Talk given at the Lattice97 conference, Edinburgh, U

The Status of a PA Endangered Bird- the Upland Sandpiper

The upland sandpiper (Bartramia Longuardia) has experienced a steep population decline in the northeastern U.S. since the mid-20th Century. In Pennsylvania it was found in less than 0.5% of atlas blocks during the Second Atlas of Breeding Birds in Pennsylvania project (2nd PBBA; 2004-09) and breeding was confirmed at only two locations. Due to continued declines and a small population size, the upland sandpiper was listed as PA endangered in 2012. During May 2012 the areas around 15 2nd PBBA upland sandpiper sightings were resurveyed by Gettysburg College students and volunteer birdwatchers. The aim was to establish whether the atlas records related to persisting populations. We used five-minute audio playback at up to 10 locations within 4km of the atlas sightings. A maximum of 19 pairs/calling male upland sandpipers were found across the state in 2012, most of them on or close to reclaimed surface mines. However, locating such a scarce species can be problematic, and it is still not known to what extent the species is under-reported. To help direct future surveys we analyzed data from the 2nd PBBA and the 2012 survey to produce a habitat suitability model for the upland sandpiper in Pennsylvania. We used a GIS framework to determine areas of suitable habitat and then stratified these by proximity to recent (2004-2012) upland sandpiper sightings. We recommend that our suitability model be used to establish a sampling protocol for more thorough statewide upland sandpiper survey every five years, in order that the species’ precarious status can be closely monitored

Zero-Discharge Fluid-Dynamic Gauging for Studying the Swelling of Soft Solid Layers

A bench-top device fluid dynamic gauging device to study the swelling or shrinking of soft solid layers immersed in a liquid environment in situ and in real time is demonstrated. A particular feature is that the volume of liquid is isolated, hence the name Zero net discharge Fluid Dynamic Gauging (ZFDG), which renders ZFDG suitable for aseptic operation. For the 1.78 mm nozzle diameter used here, calibration tests gave a resolution of ±5 μm and uncertainty of ±10 μm. Computational fluid dynamics simulations indicated that the shear stress imposed on a layer being gauged differed between the successive suction and ejection stages in ZFDG. The swelling of polyvinyl acetate (PVA) layers (about 1 mm dry thickness) and gelatin films (50-80 μm dry thickness) in aqueous solutions is reported as demonstration of a ZFDG application. There was good agreement with more cumbersome gravimetric methods. Gelatin swelled noticeably faster at high pH, above the pKa values of proline and hydroxyproline. Fitting the gelatin swelling data to a power law model indicated ‘sub-Fickian’ behaviour with a ‘diffusion index’ which increased with pH.Development of the ZFDG concept was supported by the Royal Society’s Paul Instrument Fund. Funding from Fitzwilliam College for Shiyao Wang is also gratefully acknowledged.This is the author accepted manuscript. The final version is available from ACS via http://dx.doi.org/10.1021/acs.iecr.5b0195

Confinement in QCD

The guiding lines of lattice investigations on colour confinement are reviewed, together with recent results.Comment: 7 pages,3 figures, Plenary talk at PANIC'99,10-16 June 1999,Uppsal