3,719 research outputs found
Phase transitions in a gas of anyons
We continue our numerical Monte Carlo simulation of a gas of closed loops on
a 3 dimensional lattice, however now in the presence of a topological term
added to the action corresponding to the total linking number between the
loops. We compute the linking number using certain notions from knot theory.
Adding the topological term converts the particles into anyons. Using the
correspondence that the model is an effective theory that describes the
2+1-dimensional Abelian Higgs model in the asymptotic strong coupling regime,
the topological linking number simply corresponds to the addition to the action
of the Chern-Simons term. We find the following new results. The system
continues to exhibit a phase transition as a function of the anyon mass as it
becomes small \cite{mnp}, although the phases do not change the manifestation
of the symmetry. The Chern-Simons term has no effect on the Wilson loop, but it
does affect the {\rm '}t Hooft loop. For a given configuration it adds the
linking number of the 't Hooft loop with all of the dynamical vortex loops to
the action. We find that both the Wilson loop and the 't Hooft loop exhibit a
perimeter law even though there are no massless particles in the theory, which
is unexpected.Comment: 6 pages, 5 figure
Development of a biosensor for fast point-of-care blood analysis of Troponin
We present the development of novel tetrapolar EIS biosensor for the detect of troponin. Troponin has considerable diagnostic power and provide invaluable prognostic information for risk stratification. of acute coronary syndromes. Clinical Relevance— A feasibility study was undertaken to assess the diagnostic performance of serial cardiac troponin measurements which is excellent as these structural proteins are unique to the heart and thus sensitive and specific of damage to the myocardium. clinical molecular diagnostics and home healthcare. Troponin’s biosensors would provide point-of-care and rapid decision making for the early detection of CS. Clinically relevant window of cTnI testing, concentrations from 10pM to 0.1μM were achieved
Replication of Eye-Bars and Measurement of Losses in Cross Section Due to Corrosion
Recent availability of high pressure water blasters made it possible to remove rust accumulated between the eye-bars near pin connections on the Central Bridge (Figure 1) over the Ohio River at Newport. Previously, they had never been thoroughly cleaned. Cleaning of two connections on a trial basis enabled an inspection between the bars. It was apparent then that the deterioration was critical enough to necessitate examination of the several bar groups and to accurately measure their least cross sections.
The Research Division undertook the task of replicating and measuring the bars. Figures 2 and 3 show one set of bars before and after cleaning. Considerable difficulty was encountered in making moldings or impressions because the space between the two center bars, referred to here as 1, 2, 3 and 4 (Figure 4), varied between one-quarter and one-half inch. Thin sheet metal forms (Figure 5) were used to fit around each section. These forms were then tied in place (Figure 6) and sealed around the edges with paraffin to prevent liquid leakage. A two-component compound, referred to as Sika-Flex, was used to rill these forms and provide a negative molding. Sika-Flex is a liquid joint filler which hardens into a rubbery type of material after mixing --- thereby retaining the exact shape of the bar sections after removal. Wire mesh was used inside the forms around the bars to prevent stretching or deformation of the Sika-Flex mold. Figures 7 and 8 show the forms installed.
The forms were removed after several hours of curing and taken to the laboratory where hydrostone was used to make an exact positive casting of the bar sections (Figure 9). Thereafter, each of these replicates was measured at three or four places where the least section was thought to be. A contour gauge was used to transfer these cross sections onto paper and then the area was measured with a planimeter. This method is believed to be reasonably accurate. The percent loss of section in each bar was calculated in reference to the original section taken from calculations made previously by the Maintenance Division.
A key for identifying the bars as listed is provided in Figure 10. Attached are copies of the measured sections of the respective bars listed in Table 1
Supersymmetric Sum Rules for Electromagnetic Multipoles
We derive model independent, non-perturbative supersymmetric sum rules for
the magnetic and electric multipole moments of any theory with N=1
supersymmetry. We find that in any irreducible N=1 supermultiplet the diagonal
matrix elements of the l-multipole moments are completely fixed in terms of
their off-diagonal matrix elements and the diagonal (l-1)-multipole moments.Comment: 10 pages, plain Te
A low-power recursive I/Q signal generator and current driver for bioimpedance applications
This brief presents a power-efficient quadrature signal generator and current driver application-specific integrated circuit (ASIC) for bioimpedance measurements in an electrical impedance tomography system for monitoring lung function. The signal generator is realized by a digital recursive signal oscillator with the ability of generating quadrature signals over a wide frequency range. The generated in-phase signal is applied to a current driver. It uses a balanced current-mode feedback architecture that monitors the output current through a feedback loop to minimize common-mode voltage build-up at the injection site. The quadrature signals can be used for I/Q demodulation of the measured bioimpedance. The ASIC was designed in TSMC 65 nm technology occupying an area of 0.21 mm2. The current driver can generate up to 0.7 mA current up to 200 kHz and consumes 2.7 mW power using ±0.8 V supplies
Spontaneous appearance of de novo intracranial arteriovenous malformation in hepatic cirrhosis
BACKGROUND
Intracranial arteriovenous malformations (AVMs) are rare lesions that can be congenital or acquired in early childhood, with fatal outcome in approximately 30% of cases. De novo formation during adulthood without established predisposing vascular pathology or previous brain insult is even less frequent.
CASE DESCRIPTION
We present a case of de novo brain AVM in an alcoholic Child-B cirrhosis setting. Thirty previously reported cases presented de novo AVM in patients of all ages that had another previous brain pathology or insult, such as AVM resection. Seventeen of those cases occurred in adult patients, with only 2 showing no significant predisposing factor. The present pathophysiological review covers and completes Mullan's hemodynamic "two-hit" model, associating probable thrombotic predisposition to AVM with brain insult triggering a later stage based on angiogenic stimuli.
CONCLUSIONS
This case report and literature review renews previously discussed hemodynamic theories and contributes to a fuller understanding of the pathogenesis and progression of AVM. We postulate a causal link between hepatopathy and de novo AVM, which should be strengthened and interpreted based on recent genetic data and future prospective studies
Monolithic large-signal transimpedance amplifier for use in multi-gigabit, short-range optoelectronic interconnect applications
Published versio
Offshoring emissions through used vehicle exports
Policies to reduce transport emissions often overlook the international flow of used vehicles. We quantify the rate at which used vehicles generated CO2 and pollution for all used vehicles exported from Great Britain—a globally leading used vehicle exporter—across 2005–2021. Destined for low–middle-income countries, exported vehicles fail roadworthiness standards and, even under extremely optimistic ‘functioning-as-new’ assumptions, generate at least 13–53% more emissions than scrapped or on-road vehicles
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