Comments on ``A note on first-order formalism and odd-derivative actions'' by S. Deser

We argue that the obstacles to having a first-order formalism for odd-derivative actions presented in a pedagogical note by Deser are based on examples which are not first-order forms of the original actions. The general derivation of an equivalent first-order form of the original second-order action is illustrated using the example of topologically massive electrodynamics (TME). The correct first-order formulations of the TME model keep intact the gauge invariance presented in its second-order form demonstrating that the gauge invariance is not lost in the Ostrogradsky process.Comment: 6 pages, references are adde

Clinical Efficacy of TroVax in the Treatment of Progressive Castration-resistant Prostate Cancer

With approximately 240,890 new cases expected in 2011, prostate cancer remains the leading cause of non-melanoma cancer deaths in men. Immunotherapies using viral vector-based delivery systems targeting tumor-specific antigens are being studied. Viral vector-based delivery systems present tumor-targeted antigens (TAAs) to the immune system while breaking self-tolerance. Modified vaccinia ankara has been combined with the oncofetal antigen 5T4 to create TroVax for the treatment of castration-resistant prostate cancer (CRPC). The 5T4 antigen is highly expressed in a large number of carcinomas, including prostate cancer, but is rarely expressed in healthy tissue. TroVax has been demonstrated to be safe and highly immunogenic, both as monotherapy and in combination with other standard of care therapies in colorectal, renal cell, and prostate cancer. With minimal side effects and the ability to produce a strong immunogenic response, TroVax (MVA-5T4) is a viable addition to the treatment of prostate cancer

Field evolution of the magnetic structures in Er2_2Ti2_2O7_7 through the critical point

We have measured neutron diffraction patterns in a single crystal sample of the pyrochlore compound Er$_2$Ti$_2$O$_7$ in the antiferromagnetic phase (T=0.3\,K), as a function of the magnetic field, up to 6\,T, applied along the [110] direction. We determine all the characteristics of the magnetic structure throughout the quantum critical point at $H_c$=2\,T. As a main result, all Er moments align along the field at $H_c$ and their values reach a minimum. Using a four-sublattice self-consistent calculation, we show that the evolution of the magnetic structure and the value of the critical field are rather well reproduced using the same anisotropic exchange tensor as that accounting for the local paramagnetic susceptibility. In contrast, an isotropic exchange tensor does not match the moment variations through the critical point. The model also accounts semi-quantitatively for other experimental data previously measured, such as the field dependence of the heat capacity, energy of the dispersionless inelastic modes and transition temperature.Comment: 7 pages; 8 figure

Geriatric Emergency Department Innovations: Transitional Care Nurses and Hospital Use

OBJECTIVES: To examine the effect of an emergency department (ED)-based transitional care nurse (TCN) on hospital use. DESIGN: Prospective observational cohort. SETTING: Three U.S. (NY, IL, NJ) EDs from January 1, 2013, to June 30, 2015. PARTICIPANTS: Individuals aged 65 and older in the ED (N = 57,287). INTERVENTION: The intervention was first TCN contact. Controls never saw a TCN during the study period. MEASUREMENTS: We examined sociodemographic and clinical characteristics associated with TCN use and outcomes. The primary outcome was inpatient admission during the index ED visit (admission on Day 0). Secondary outcomes included cumulative 30-day admission (any admission on Days 0-30) and 72-hour ED revisits. RESULTS: A TCN saw 5,930 (10%) individuals, 42% of whom were admitted. After accounting for observed selection bias using entropy balance, results showed that when compared to controls, TCN contact was associated with lower risk of admission (site 1: -9.9% risk of inpatient admission, 95% confidence interval (CI) = -12.3% to -7.5%; site 2: -16.5%, 95% CI = -18.7% to -14.2%; site 3: -4.7%, 95% CI = -7.5% to -2.0%). Participants with TCN contact had greater risk of a 72-hour ED revisit at two sites (site 1: 1.5%, 95% CI = 0.7-2.3%; site 2: 1.4%, 95% CI = 0.7-2.1%). Risk of any admission within 30 days of the index ED visit also remained lower for TCN patients at both these sites (site 1: -7.8%, 95% CI = -10.3% to -5.3%; site 2: -13.8%, 95% CI = -16.1% to -11.6%). CONCLUSION: Targeted evaluation by geriatric ED transitions of care staff may be an effective delivery innovation to reduce risk of inpatient admission

General relativistic corrections to the Sagnac effect

The difference in travel time of corotating and counter-rotating light waves in the field of a central massive and spinning body is studied. The corrections to the special relativistic formula are worked out in a Kerr field. Estimation of numeric values for the Earth and satellites in orbit around it show that a direct measurement is in the order of concrete possibilities.Comment: REVTex, accepted for publication on Phys. Rev.

Quantum Phase and Quantum Phase Operators: Some Physics and Some History

After reviewing the role of phase in quantum mechanics, I discuss, with the aid of a number of unpublished documents, the development of quantum phase operators in the 1960's. Interwoven in the discussion are the critical physics questions of the field: Are there (unique) quantum phase operators and are there quantum systems which can determine their nature? I conclude with a critique of recent proposals which have shed new light on the problem.Comment: 19 pages, 2 Figs. taken from published articles, LaTeX, to be published in Physica Scripta, Los Alamos preprint LA-UR-92-352

Two Mathematically Equivalent Versions of Maxwell's Equations

This paper is a review of the canonical proper-time approach to relativistic mechanics and classical electrodynamics. The purpose is to provide a physically complete classical background for a new approach to relativistic quantum theory. Here, we first show that there are two versions of Maxwell's equations. The new version fixes the clock of the field source for all inertial observers. However now, the (natural definition of the effective) speed of light is no longer an invariant for all observers, but depends on the motion of the source. This approach allows us to account for radiation reaction without the Lorentz-Dirac equation, self-energy (divergence), advanced potentials or any assumptions about the structure of the source. The theory provides a new invariance group which, in general, is a nonlinear and nonlocal representation of the Lorentz group. This approach also provides a natural (and unique) definition of simultaneity for all observers. The corresponding particle theory is independent of particle number, noninvariant under time reversal (arrow of time), compatible with quantum mechanics and has a corresponding positive definite canonical Hamiltonian associated with the clock of the source. We also provide a brief review of our work on the foundational aspects of the corresponding relativistic quantum theory. Here, we show that the standard square-root and the Dirac equations are actually two distinct spin-$\tfrac{1}{2}$ particle equations.Comment: Appeared: Foundations of Physic

On the verge of Umdeutung in Minnesota: Van Vleck and the correspondence principle (Part One)

In October 1924, the Physical Review, a relatively minor journal at the time, published a remarkable two-part paper by John H. Van Vleck, working in virtual isolation at the University of Minnesota. Van Vleck combined advanced techniques of classical mechanics with Bohr's correspondence principle and Einstein's quantum theory of radiation to find quantum analogues of classical expressions for the emission, absorption, and dispersion of radiation. For modern readers Van Vleck's paper is much easier to follow than the famous paper by Kramers and Heisenberg on dispersion theory, which covers similar terrain and is widely credited to have led directly to Heisenberg's "Umdeutung" paper. This makes Van Vleck's paper extremely valuable for the reconstruction of the genesis of matrix mechanics. It also makes it tempting to ask why Van Vleck did not take the next step and develop matrix mechanics himself.Comment: 82 page

Informed consent for clinical trials in acute coronary syndromes and stroke following the European Clinical Trials Directive: investigators' experiences and attitudes

<p>Abstract</p> <p>Background</p> <p>During clinical trials in emergency medicine, providing appropriate oral and written information to a patient is usually a challenge. There is little published information regarding patients' opinions and competence to provide informed consent, nor on physicians' attitudes towards the process. We have investigated the problem of obtaining consent from patients in emergency-setting clinical trials (such as acute coronary syndromes (ACS) and stroke) from a physicians' perspective.</p> <p>Methods</p> <p>A standardised anonymous 14-item questionnaire was distributed to Polish cardiac and stroke centres.</p> <p>Results</p> <p>Two hundred and fourteen informative investigator responses were received. Of these investigators, 73.8% had experience with ACS and 25.2% had experience with acute stroke trials (and 1% with both fields). The complete model of informed consent (embracing all aspects required by Good Clinical Practice (GCP) and law) was used in 53.3% of cases in emergency settings, whereas the legal option of proxy consent was not used at all. While less than 15% of respondents considered written information to have been fully read by patients, 80.4% thought that the amount of information being given to emergency patients is too lengthy. Although there is no legal obligation, more than half of the investigators sought parallel consent (assent) from patients' relatives. Most investigators confirmed that they would adopt the model proposed by the GCP guidelines: abbreviated verbal and written consent in emergency conditions with obligatory "all-embracing" deferred consent to continue the trial once the patient is able to provide it. However, this model would not follow current Polish and European legislation.</p> <p>Conclusion</p> <p>An update of national and European regulations is required to enable implementation of the emergency trial consent model referred to in GCP guidelines.</p