The uniqueness of the invariant polarisation-tensor field for spin-1 particles in storage rings

We argue that the invariant tensor field introduced in [1] is unique under the condition that the invariant spin field is unique, and thereby complete that part of the discussion in that paper.Comment: 8 page

Solving String Field Equations: New Uses for Old Tools

It is argued that the (NS-sector) superstring field equations are integrable, i.e. their solutions are obtainable from linear equations. We adapt the 25-year-old solution-generating "dressing" method and reduce the construction of nonperturbative superstring configurations to a specific cohomology problem. The application to vacuum superstring field theory is outlined.Comment: Talk presented by O.L. at the 35th International Symposium Ahrenshoop on the Theory of Elementary Particles, Berlin, Germany, 26-30 Aug 2002; v2: minor corrections, textheight adjuste

Book Review: The Divine Feminine Tao Te Ching: A New Translation and Commentary, by Rosemarie Anderson

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Management of asthma exacerbations in children

Asthma exacerbations are episodes of worsening asthma symptoms with shortness of breath, cough, wheeze and/or tight chest that require an increase in asthma treatment. A major change in the recommendations for managing mild asthma exacerbations is the move away from using inhaled short-acting beta-2 agonists (SABAs) as the sole reliever, toward a combination of a rapid-onset, long-acting beta-2 agonist, formoterol, in combination with an inhaled corticosteroid (ICS), or a SABA used together with an ICS in separate inhalers, in older children and adolescents. In children <11 years of age who are adherent to daily ICS treatment, the ICS dose should not be increased short term. A written asthma plan should include instructions on how to self-manage asthma exacerbations, and when to present to a medical facility. Oxygen is an essential component of the management of asthma exacerbations at both primary care and emergency department facilities, together with inhaled SABAs via metered-dose inhaler and spacer, and oral corticosteroids

Carrier-envelope phase control over pathway interference in strong-field dissociation of H2+_2^+

The dissociation of an H$_2^+$ molecular-ion beam by linearly polarized, carrier-envelope-phase-tagged 5 fs pulses at 4$\times10^{14}$W/cm$^2$ with a central wavelength of 730 nm was studied using a coincidence 3D momentum imaging technique. Carrier-envelope-phase-dependent asymmetries in the emission direction of H$^+$ fragments relative to the laser polarization were observed. These asymmetries are caused by interference of odd and even photon number pathways, where net-zero photon and 1-photon interference predominantly contributes at H$^+$+H kinetic energy releases of 0.2 -- 0.45 eV, and net-2-photon and 1-photon interference contributes at 1.65 -- 1.9 eV. These measurements of the benchmark H$_2^+$ molecule offer the distinct advantage that they can be quantitatively compared with \textit{ab initio} theory to confirm our understanding of strong-field coherent control via the carrier-envelope phase

Continuous image distortion by astrophysical thick lenses

Image distortion due to weak gravitational lensing is examined using a non-perturbative method of integrating the geodesic deviation and optical scalar equations along the null geodesics connecting the observer to a distant source. The method we develop continuously changes the shape of the pencil of rays from the source to the observer with no reference to lens planes in astrophysically relevant scenarios. We compare the projected area and the ratio of semi-major to semi-minor axes of the observed elliptical image shape for circular sources from the continuous, thick-lens method with the commonly assumed thin-lens approximation. We find that for truncated singular isothermal sphere and NFW models of realistic galaxy clusters, the commonly used thin-lens approximation is accurate to better than 1 part in 10^4 in predicting the image area and axes ratios. For asymmetric thick lenses consisting of two massive clusters separated along the line of sight in redshift up to \Delta z = 0.2, we find that modeling the image distortion as two clusters in a single lens plane does not produce relative errors in image area or axes ratio more than 0.5%Comment: accepted to GR

Theme Overview: Agriculture and Water Quality in the Cornbelt: Overview of Issues and Approaches

Resource /Energy Economics and Policy, Q25,

Ask a Hypothetical Question, Get a Valuable Answer?

The authors model the recreation demand for Iowa wetlands, combining survey data on both actual usage patterns (i.e., revealed preferences) and anticipated changes to those patterns under hypothetical increases in trip costs (i.e., stated preferences). They formulate and test specific hypotheses concerning potential sources of bias in each data type and consistently reject consistency between the two data sources, both in terms of implied wetland values and underlying preference parameters. The authors pay careful attention to the interpretations of the test results, noting particularly how the interpretation of the same results can vary with the school of thought of the reader