Designing an international policy and legal framework for the control of emerging infectious diseases: first steps.

As the pace of emergence and reemergence of infectious diseases quickens, the International Health Regulations, which have served as the legal and policy framework of epidemic control for 45 years, are being revised by the World Health Organization (WHO). In this article, we review the recent history, legal construction, and application of these regulations and related international treaty-based sanitary measures, especially the General Agreement on Tariffs and Trade and the Agreement on the Application of Sanitary and Phytosanitary Measures, and the history of applying the regulations in the maritime and aviation industries. This review indicates that revision efforts should address 1) the limited scope of disease syndromes (and reporters of these syndromes) now in the regulations and 2) the mismatch between multisectoral factors causing disease emergence and the single agency (WHO) administering the regulations. The revised regulations should expand the scope of reporting and simultaneously broaden international agency coordination

Conformal GaP layers on Si wire arrays for solar energy applications

We report conformal, epitaxial growth of GaP layers on arrays of Si microwires. Silicon wires grown using chlorosilane chemical vapor deposition were coated with GaP grown by metal-organic chemical vapor deposition. The crystalline quality of conformal, epitaxial GaP/Si wire arrays was assessed by transmission electron microscopy and x-ray diffraction. Hall measurements and photoluminescence show p- and n-type doping with high electron mobility and bright optical emission. GaP pn homojunction diodes on planar reference samples show photovoltaic response with an open circuit voltage of 660 mV

Local Casimir Energies for a Thin Spherical Shell

The local Casimir energy density for a massless scalar field associated with step-function potentials in a 3+1 dimensional spherical geometry is considered. The potential is chosen to be zero except in a shell of thickness $\delta$, where it has height $h$, with the constraint $h\delta=1$. In the limit of zero thickness, an ideal $\delta$-function shell is recovered. The behavior of the energy density as the surface of the shell is approached is studied in both the strong and weak coupling regimes. The former case corresponds to the well-known Dirichlet shell limit. New results, which shed light on the nature of surface divergences and on the energy contained within the shell, are obtained in the weak coupling limit, and for a shell of finite thickness. In the case of zero thickness, the energy has a contribution not only from the local energy density, but from an energy term residing entirely on the surface. It is shown that the latter coincides with the integrated local energy density within the shell. We also study the dependence of local and global quantities on the conformal parameter. In particular new insight is provided on the reason for the divergence in the global Casimir energy in third order in the coupling.Comment: 16 pages, revtex 4, no figures. Major additions, clarifications, and corections, references adde

Exact results for Casimir interactions between dielectric bodies: The weak-coupling or van der Waals Limit

In earlier papers we have applied multiple scattering techniques to calculate Casimir forces due to scalar fields between different bodies described by delta function potentials. When the coupling to the potentials became weak, closed-form results were obtained. We simplify this weak-coupling technique and apply it to the case of tenuous dielectric bodies, in which case the method involves the summation of van der Waals (Casimir-Polder) interactions. Once again exact results for finite bodies can be obtained. We present closed formulas describing the interaction between spheres and between cylinders, and between an infinite plate and a retangular slab of finite size. For such a slab, we consider the torque acting on it, and find non-trivial equilibrium points can occur.Comment: 4 pages, 3 figure

Assessment of zinc phosphide bait shyness and tools for reducing flavor aversions

Prairie voles (Microtus ochrogaster Wagner) cause extensive damage in agricultural, suburban, and urban environments. Control of these animals has historically relied on the use of anticoagulant rodenticides and zinc phosphide. However, shyness to zinc phosphide baits has reduced its efficacy. The aim of this study was to evaluate the factors involved in zinc phosphide bait shyness through preference testing. Baits were made using a rolled oat base and contained various combinations of the components of zinc phosphide baits such as lecithin, magnesium carbonate and known flavor modulators sodium cyclamate and zinc sulfate. Encapsulation of zinc phosphide was also tested as a potential means to mask undesirable flavor qualities of the compound. Consumption of test baits was measured in four day laboratory feeding trials. Results demonstrated that numerous components of current bait formulations serve as salient cues during conditioned aversions and therefore may contribute to bait shyness. Vole avoidance of zinc sulfate and sodium cyclamate revealed that these potential additives would not decrease bait shyness. Encapsulation of zinc phosphide may have masked some of the negative flavor cues and therefore should be considered in future bait development. This study suggests that, since voles are able to distinguish components of current bait formulations, varying composition of zinc phosphide baits between applications may serve to reduce bait shyness

Assessment of cabergoline as a reproductive inhibitor in coyotes (\u3ci\u3eCanis latrans\u3c/i\u3e)

The efficacy of three oral formulations (gelatin capsule, tablet, oil base) and five dosages (50, 100, 250, 500, 1000 μg) of cabergoline to disrupt reproduction in coyotes (Canis latrans) was evaluated. The type of formulation used had no effect on plasma progesterone and prolactin concentrations or on mean litter size. No adverse side effects (for example, vomiting, anorexia, diarrhea) were observed despite the use of doses of up to 20 times the therapeutic dose used for domestic dogs and cats. All coyotes treated with 50, 100, 250 and 500 μg cabergoline whelped, but plasma progesterone concentrations in these coyotes were lower (P ≤ 0.07) than in control animals at day 7 after treatment. Ten of 11 females treated with 1000 yg cabergoline whelped, but progesterone concentrations in these coyotes were lower than in control animals up to day 14 after treatment ( P ≤ 0.04). Dosages of 1 000 μg cabergoline decreased blood serum prolactin (P ≤ 0.1 0) and progesterone (P ≤ 0.06) concentrations, but apparently failed to decrease progesterone below the threshold necessary to maintain pregnancy in all but one animal. However, progressive inhibition of prolactin and progesterone with increasing doses of cabergoline indicated that higher dosages might be effective in coyotes. Survival of pups born to cabergoline-treated females was not different (P \u3c 0.001) from that of pups born to control females, but mean litter size was smaller for females treated with cabergoline (P ≤ 0.073) than for the control females. Although all cabergoline treatments in this study were ineffective at preventing reproduction in coyotes, progressive inhibition of prolactin and progesterone with increasing dosages of cabergoline indicates that higher doses might be effective in preventing reproduction in coyotes. However, the physiological differences from other canine species in dopamine D2 receptors and mechanisms of luteal support may ultimately prevent the use of cabergoline for reproductive control in coyotes

How Does Casimir Energy Fall?

Doubt continues to linger over the reality of quantum vacuum energy. There is some question whether fluctuating fields gravitate at all, or do so anomalously. Here we show that for the simple case of parallel conducting plates, the associated Casimir energy gravitates just as required by the equivalence principle, and that therefore the inertial and gravitational masses of a system possessing Casimir energy $E_c$ are both $E_c/c^2$. This simple result disproves recent claims in the literature. We clarify some pitfalls in the calculation that can lead to spurious dependences on coordinate system.Comment: 5 pages, 1 figure, REVTeX. Minor revisions, including changes in reference

Electromagnetic semitransparent δ\delta-function plate: Casimir interaction energy between parallel infinitesimally thin plates

We derive boundary conditions for electromagnetic fields on a $\delta$-function plate. The optical properties of such a plate are shown to necessarily be anisotropic in that they only depend on the transverse properties of the plate. We unambiguously obtain the boundary conditions for a perfectly conducting $\delta$-function plate in the limit of infinite dielectric response. We show that a material does not "optically vanish" in the thin-plate limit. The thin-plate limit of a plasma slab of thickness $d$ with plasma frequency $\omega_p^2=\zeta_p/d$ reduces to a $\delta$-function plate for frequencies ($\omega=i\zeta$) satisfying $\zeta d \ll \sqrt{\zeta_p d} \ll 1$. We show that the Casimir interaction energy between two parallel perfectly conducting $\delta$-function plates is the same as that for parallel perfectly conducting slabs. Similarly, we show that the interaction energy between an atom and a perfect electrically conducting $\delta$-function plate is the usual Casimir-Polder energy, which is verified by considering the thin-plate limit of dielectric slabs. The "thick" and "thin" boundary conditions considered by Bordag are found to be identical in the sense that they lead to the same electromagnetic fields.Comment: 21 pages, 7 figures, references adde

Characterization of Two Distinct Calcium-Binding Sites in the Amino-Terminus of Human Profilaggrin

Profilaggrin is a large phosphorylated protein (approximately 400 kDa In humans) that is expressed in the granular cells of epidermis where it forms a major component of keratohyalin. It consists of multiple copies of similar filaggrin units plus amino- and carboxy-terminal domains that differ from filaggrin. Proteolytic processing of profilaggrin during terminal differentiation results in the removal of these domains and generation of monomeric filaggrin units, which associate with keratin intermediate filaments to form macrofibrils in the stratum corneum. The amino-terminal domain contains two calcium-binding motifs similar to the EF-hands found in the S-100 family of calcium-binding proteins. In this report, we expressed the 293-residue amino-terminal pro-domain of human profilaggrin as a polyhistidine fusion protein in Escherichia coli, and characterized calcium binding by a 45Ca++ binding assay and fluorescence emission spectroscopy. fluorescence measurements indicated that the profilaggrin polypeptide undergoes conformational changes upon the removal of Ca++ with ethylenediamine tetraacetic acid, demonstrating the presence of two calcium-binding sites with affinities for calcium that differ ninefold (1.4 × 10-4 M and 1.2 × 10-3 M). We suggest that this functional calcium-binding domain at the amino-terminus of human profilaggrin plays a role in profilaggrin processing and in other calcium-dependent processes during terminal differentiation of the epidermis

Selective addressing of high-rank atomic polarization moments

We describe a method of selective generation and study of polarization moments of up to the highest rank $\kappa=2F$ possible for a quantum state with total angular momentum $F$. The technique is based on nonlinear magneto-optical rotation with frequency-modulated light. Various polarization moments are distinguished by the periodicity of light-polarization rotation induced by the atoms during Larmor precession and exhibit distinct light-intensity and frequency dependences. We apply the method to study polarization moments of $^{87}$Rb atoms contained in a vapor cell with antirelaxation coating. Distinct ultra-narrow (1-Hz wide) resonances, corresponding to different multipoles, appear in the magnetic-field dependence of the optical rotation. The use of the highest-multipole resonances has important applications in quantum and nonlinear optics and in magnetometry.Comment: 5 pages, 6 figure