Wave Equation for Sound in Fluids with Vorticity

We use Clebsch potentials and an action principle to derive a closed system of gauge invariant equations for sound superposed on a general background flow. Our system reduces to the Unruh (1981) and Pierce (1990) wave equations when the flow is irrotational, or slowly varying. We illustrate our formalism by applying it to waves propagating in a uniformly rotating fluid where the sound modes hybridize with inertial waves.Comment: RevTeX, 27page

Maximizing the benefits and minimizing the risks of intervention programs to address micronutrient malnutrition: symposium report.

Interventions to address micronutrient deficiencies have large potential to reduce the related disease and economic burden. However, the potential risks of excessive micronutrient intakes are often not well determined. During the Global Summit on Food Fortification, 9-11 September 2015, in Arusha, a symposium was organized on micronutrient risk-benefit assessments. Using case studies on folic acid, iodine and vitamin A, the presenters discussed how to maximize the benefits and minimize the risks of intervention programs to address micronutrient malnutrition. Pre-implementation assessment of dietary intake, and/or biomarkers of micronutrient exposure, status and morbidity/mortality is critical in identifying the population segments at risk of inadequate and excessive intake. Dietary intake models allow to predict the effect of micronutrient interventions and their combinations, e.g. fortified food and supplements, on the proportion of the population with intakes below adequate and above safe thresholds. Continuous monitoring of micronutrient intake and biomarkers is critical to identify whether the target population is actually reached, whether subgroups receive excessive amounts, and inform program adjustments. However, the relation between regular high intake and adverse health consequences is neither well understood for many micronutrients, nor do biomarkers exist that can detect them. More accurate and reliable biomarkers predictive of micronutrient exposure, status and function are needed to ensure effective and safe intake ranges for vulnerable population groups such as young children and pregnant women. Modelling tools that integrate information on program coverage, dietary intake distribution and biomarkers will further enable program makers to design effective, efficient and safe programs

Landauer Conductance of Luttinger Liquids with Leads

We show that the dc conductance of a quantum wire containing a Luttinger liquid and attached to non-interacting leads is given by $e^2/h$ per spin orientation, regardless of the interactions in the wire. This explains the recent observations of the absence of conductance renormalization in long high-mobility $GaAs$ wires by Tarucha, Honda and Saku (Solid State Communications {\bf 94}, 413 (1995)).Comment: 4 two-column pages, RevTeX + 1 uuencoded figure

Proposal for reading out anyon qubits in non-abelian ν=12/5\nu = 12/5 quantum Hall state

To detect non-abelian statistics in the $\nu = 12/5$ quantum Hall state through interferometry, we apply an analysis similar to the ones proposed for the non-abelian $\nu = 5/2$ quantum Hall state. The result is that the amplitude of the Aharonov-Bohm oscillation of this interference is dependent on the internal states of quasiholes, but, in contrast to the $\nu = 5/2$ quantum Hall state, independent of the number of quasiholes. However, if the quasiholes are in a superposition state, it is necessary for the interferometer to have certain additional features to obtain the coefficients.Comment: 16 pages, 2 figures, Latex. Reference added, some errors corrected, some content changed, some changes in the abstrac

Inferior Vena Cava Assessment Correlation with CVP and Plethora in Tamponade

AbstractBedside assessment of intravascular volume status plays an important role in the management of critically ill patients, guiding fluid replacement therapy and the use of vasopressor agents. Despite controversy in the existing evidence, many clinicians advocate the use of inferior vena cava ultrasound (IVC-US) in the assessment of intravascular volume status in critically ill patients. Respirophasic variation in IVC diameter may provide useful information regarding intravascular volume status, particularly in patients with high and low caval indices. However, due to conflicting results of small-scale clinical trials of divergent sample populations, there is insufficient evidence to support routine US assessment of the IVC to determine fluid responsiveness in spontaneous breathing with circulatory compromise. Additional large-scale clinical trials are required to determine the accuracy of IVC-US measurements in diverse populations and to ascertain the effects on IVC dimensions that result from cardiac dysfunction and intra-abdominal hypertension

A Comparison of Functional Models for Use in the Function-Failure Design Method

When failure analysis and prevention, guided by historical design knowledge, are coupled with product design at its conception, shorter design cycles are possible. By decreasing the design time of a product in this manner, design costs are reduced and the product will better suit the customer s needs. Prior work indicates that similar failure modes occur with products (or components) with similar functionality. To capitalize on this finding, a knowledge base of historical failure information linked to functionality is assembled for use by designers. One possible use for this knowledge base is within the Elemental Function-Failure Design Method (EFDM). This design methodology and failure analysis tool begins at conceptual design and keeps the designer cognizant of failures that are likely to occur based on the product s functionality. The EFDM offers potential improvement over current failure analysis methods, such as FMEA, FMECA, and Fault Tree Analysis, because it can be implemented hand in hand with other conceptual design steps and carried throughout a product s design cycle. These other failure analysis methods can only truly be effective after a physical design has been completed. The EFDM however is only as good as the knowledge base that it draws from, and therefore it is of utmost importance to develop a knowledge base that will be suitable for use across a wide spectrum of products. One fundamental question that arises in using the EFDM is: At what level of detail should functional descriptions of components be encoded? This paper explores two approaches to populating a knowledge base with actual failure occurrence information from Bell 206 helicopters. Functional models expressed at various levels of detail are investigated to determine the necessary detail for an applicable knowledge base that can be used by designers in both new designs as well as redesigns. High level and more detailed functional descriptions are derived for each failed component based on NTSB accident reports. To best record this data, standardized functional and failure mode vocabularies are used. Two separate function-failure knowledge bases are then created aid compared. Results indicate that encoding failure data using more detailed functional models allows for a more robust knowledge base. Interestingly however, when applying the EFDM, high level descriptions continue to produce useful results when using the knowledge base generated from the detailed functional models

Correlators and fractional statistics in the quantum Hall bulk

We derive single-particle and two-particle correlators of anyons in the presence of a magnetic field in the lowest Landau level. We show that the two-particle correlator exhibits signatures of fractional statistics which can distinguish anyons from their fermionic and bosonic counterparts. These signatures include the zeroes of the two-particle correlator and its exclusion behavior. We find that the single-particle correlator in finite geometries carries valuable information relevant to experiments in which quasiparticles on the edge of a quantum Hall system tunnel through its bulk.Comment: 4 pages, 3 figures, RevTe