9,666 research outputs found
Recommended from our members
Evaluation of two eco-friendly neutralizers for a spectrum of tissue fixatives for biomedical applications.
Formaldehyde is a widely used aldehyde in biomedical applications, including tissue fixation. It is this same fixative property that can result in toxicity if aldehydes are improperly discarded. A proper neutralization of aldehyde waste products can address this, thereby reducing both health and environmental toxicity concerns. In this study two commercially available products designed to neutralize formaldehyde were evaluated, including neutralization of laboratory derived tissue fixative waste. The primary selection criteria for inclusion in the study were: their ease of use (based on product instructions); the two products assert high levels of formaldehyde neutralization (below 20Â ppm) relative to other neutralizing products and their lack of generation of polymeric residues that can clog drains. Both products tested were relatively easy to use and both achieved <10Â ppm residual levels of formaldehyde from standard formalin and glutaraldehyde preparations used in research and clinical laboratories
Policies for economic development
This paper looks at the economic policies and institutions needed to generate and sustain economic growth and development. It argues that policy and institutional reforms are needed in three broad areas. First, the need for a fiscal policy and overall macroeconomic framework that ensures stability is critical. Second, sectoral pricing and investments ought to address key constraints to growth while respecting the requirement for stability. Third, the domestic economy needs to be integrated with the global economy to increase competition and improve competitiveness. Policy and institutional reforms in these areas are necessary both for adjusting to exogenous changes and for ensuring long-term growth and development. To enable the appropriate policies to emerge in these areas, government must act competently in the spheres that are its proper concern. The paper concludes with a brief discussion of some of the major remaining uncertainties.Environmental Economics&Policies,Economic Theory&Research,Economic Stabilization,Achieving Shared Growth,Macroeconomic Management
The Calogero-Fran\c{c}oise integrable system: algebraic geometry, Higgs fields, and the inverse problem
We review the Calogero-Fran\c{c}oise integrable system, which is a
generalization of the Camassa-Holm system. We express solutions as (twisted)
Higgs bundles, in the sense of Hitchin, over the projective line. We use this
point of view to (a) establish a general answer to the question of
linearization of isospectral flow and (b) demonstrate, in the case of two
particles, the dynamical meaning of the theta divisor of the spectral curve in
terms of mechanical collisions. Lastly, we outline the solution to the inverse
problem for CF flows using Stieltjes' continued fractions.Comment: 22 pages, 2 figure
Gelfand-Tsetlin polytopes and Feigin-Fourier-Littelmann polytopes as marked poset polytopes
Stanley (1986) showed how a finite partially ordered set gives rise to two
polytopes, called the order polytope and chain polytope, which have the same
Ehrhart polynomial despite being quite different combinatorially. We generalize
his result to a wider family of polytopes constructed from a poset P with
integers assigned to some of its elements.
Through this construction, we explain combinatorially the relationship
between the Gelfand-Tsetlin polytopes (1950) and the Feigin-Fourier-Littelmann
polytopes (2010), which arise in the representation theory of the special
linear Lie algebra. We then use the generalized Gelfand-Tsetlin polytopes of
Berenstein and Zelevinsky (1989) to propose conjectural analogues of the
Feigin-Fourier-Littelmann polytopes corresponding to the symplectic and odd
orthogonal Lie algebras.Comment: 12 page
A real-time audio spectral analyser using active filters with adjustable parameters
Imperial Users onl
Cyclic Sieving of Increasing Tableaux and small Schr\"oder Paths
An increasing tableau is a semistandard tableau with strictly increasing rows
and columns. It is well known that the Catalan numbers enumerate both
rectangular standard Young tableaux of two rows and also Dyck paths. We
generalize this to a bijection between rectangular 2-row increasing tableaux
and small Schr\"oder paths. We demonstrate relations between the jeu de taquin
for increasing tableaux developed by H. Thomas and A. Yong and the
combinatorics of tropical frieze patterns. We then use this jeu de taquin to
present new instances of the cyclic sieving phenomenon of V. Reiner, D.
Stanton, and D. White, generalizing results of D. White and of J. Stembridge.Comment: 20 page
Shock temperatures in calcite (CaCO3): Implication for shock induced decomposition
The temperatures induced in crystalline calcite upon planar shock compression (95–160 GPa) are reported from two-stage light gas-gun experiments. The temperatures are obtained fitting 6-channel optical pyrometer radiances in the 450 to 900 nm range, to a Planck radiation law temperature varied from 3300 to 5400 K. Calculations demonstrate that the temperatures are some 400 to 1350 K lower than if either shock-induced melting and/or disproportionation of calcite behind the shock front was not occurring. Here calcite is modeled as disproportionating into a molecular liquid, or a solid CaO plus CO2 gas. For temperature calculations, specific heat at constant volume for one mole of CO2 is taken to be 6.7R as compared to 9R in the solid state; whereas calcite and CaO have their solid state values (15R and 6R). Calculations also suggest that the onset of decomposition in calcite to CaO and CO2 during loading occurs at ~75±10 GPa, along the Hugoniot whereas decomposition begins upon unloading from 18 GPa. The 18 GPa value is based on comparison of VISAR measurements of particle velocity profiles induced upon isentropic expansion with one-dimensional numerical simulation
IFN-gamma-mediated suppression of coronavirus replication in glial-committed progenitor cells.
The neurotropic JHM strain of mouse hepatitis virus (JHMV) replicates primarily within glial cells following intracranial inoculation of susceptible mice, with relative sparing of neurons. This study demonstrates that glial cells derived from neural progenitor cells are susceptible to JHMV infection and that treatment of infected cells with IFN-gamma inhibits viral replication in a dose-dependent manner. Although type I IFN production is muted in JHMV-infected glial cultures, IFN-beta is produced following IFN-gamma-treatment of JHMV-infected cells. Also, direct treatment of infected glial cultures with recombinant mouse IFN-alpha or IFN-beta inhibits viral replication. IFN-gamma-mediated control of JHMV replication is dampened in glial cultures derived from the neural progenitor cells of type I receptor knock-out mice. These data indicate that JHMV is capable of infecting glial cells generated from neural progenitor cells and that IFN-gamma-mediated control of viral replication is dependent, in part, on type I IFN secretion
Human Factors in Automated and Robotic Space Systems: Proceedings of a symposium. Part 1
Human factors research likely to produce results applicable to the development of a NASA space station is discussed. The particular sessions covered in Part 1 include: (1) system productivity -- people and machines; (2) expert systems and their use; (3) language and displays for human-computer communication; and (4) computer aided monitoring and decision making. Papers from each subject area are reproduced and the discussions from each area are summarized
- …