Analyticity, Unitarity and One-loop Graviton Corrections to Compton Scattering

We compute spin-flip cross section for graviton photoproduction on a spin-1/2 target of finite mass. Using this tree-level result, we find one-loop graviton correction to the spin-flip low-energy forward Compton scattering amplitude by using Gerasimov-Drell-Hearn sum rule. We show that this result agrees with the corresponding perturbative computations, implying the validity of the sum rule at one-loop level, contrary to the previous claims. We discuss possible effects from the black hole production and string Regge trajectory exchange at very high energies. These effects seem to soften the UV divergence present at one-loop graviton level. Finally, we discuss the relation of these observations with the models that involve extra dimensions.Comment: 15 pages, 3 figure

Revealed Preference Dimension via Matrix Sign Rank

Given a data-set of consumer behaviour, the Revealed Preference Graph succinctly encodes inferred relative preferences between observed outcomes as a directed graph. Not all graphs can be constructed as revealed preference graphs when the market dimension is fixed. This paper solves the open problem of determining exactly which graphs are attainable as revealed preference graphs in $d$-dimensional markets. This is achieved via an exact characterization which closely ties the feasibility of the graph to the Matrix Sign Rank of its signed adjacency matrix. The paper also shows that when the preference relations form a partially ordered set with order-dimension $k$, the graph is attainable as a revealed preference graph in a $k$-dimensional market.Comment: Submitted to WINE `1

A Matrix Model for Baryons and Nuclear Forces

We propose a new matrix model describing multi-baryon systems. We derive the action from open string theory on the wrapped baryon vertex D-branes embedded in the D4-D8 model of large N holographic QCD. The positions of k baryons are unified into k x k matrices, with spin/isospin of the baryons encoded in a set of k-vectors. Holographic baryons are known to be very small in the large 't Hooft coupling limit, and our model offers a better systematic approach to dynamics of such baryons at short distances. We compute energetics and spectra (k=1), and also short-distance nuclear force (k=2). In particular, we obtain a new size of the holographic baryon and find a precise form of the repulsive core of nucleons. This matrix model complements the instanton soliton picture of holographic baryons, whose small size turned out to be well below the natural length scale of the approximation involved there. Our results show that, nevertheless, the basic properties of holographic baryons obtained there are robust under stringy corrections within a few percents.Comment: 30 pages. v3: more comments added, published versio

Diabetic ketoacidosis complicated by the use of ecstasy: a case report

<p>Abstract</p> <p>Introduction</p> <p>Ecstasy (3,4-methylenedioxymethamphetamin), a hallucinogenic amphetamine, is often used by young people, especially at 'raves'. This illicit drug can cause many metabolic changes and its use, when associated with prolonged exercise, may exacerbate ketoacidosis in type 1 diabetic patients.</p> <p>Case presentation</p> <p>This is a case of ketoacidosis complicated by the use of ecstasy in a 19-year-old insulin-dependent diabetic Caucasian woman.</p> <p>Conclusion</p> <p>The use of ecstasy may trigger diabetic ketoacidosis in patients with a preexisting metabolic disorder</p

Polysomnographic and Subjective Sleep Predictors of Alcoholic Relapse

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65219/1/j.1530-0277.1998.tb03995.x.pd

Liquid-gas phase transition in nuclear multifragmentation

The equation of state of nuclear matter suggests that at suitable beam energies the disassembling hot system formed in heavy ion collisions will pass through a liquid-gas coexistence region. Searching for the signatures of the phase transition has been a very important focal point of experimental endeavours in heavy ion collisions, in the last fifteen years. Simultaneously theoretical models have been developed to provide information about the equation of state and reaction mechanisms consistent with the experimental observables. This article is a review of this endeavour.Comment: 63 pages, 27 figures, submitted to Adv. Nucl. Phys. Some typos corrected, minor text change

Relationship between psychological factors and performance-based and self-reported disability in chronic low back pain

Cross sectional study, performed in an outpatient university based pain rehabilitation setting. To analyze the relationship between psychological factors (psychosocial distress, depression, self efficacy, self-esteem, fear of movement, pain cognitions and coping reactions) and performance-based and self-reported disability, as measured with a Functional Capacity Evaluation (FCE) and the Roland Morris Disability Questionnaire (RMDQ), in patients with chronic low back pain (CLBP). It has been suggested that a strong relationship exists between psychological factors and disability in patients with CLBP. In former research disability was often measured by self-report and seldom performance-based. Study sample consisted of 92 patients with CLBP admitted for multidisciplinary rehabilitation. Prior to treatment, all patients completed questionnaires to measure psychological factors and self-reported disability, and performed an FCE to measure performance-based disability. Correlation coefficients between psychological variables and FCE and self-reported disability were calculated. Multivariate linear regression analyses were performed with self-reported or performance based disability measures as outcome variables, and psychological measures as predictor variables. Out of 42 relations analyzed, 5 were statistically significant. This concerned one significant correlation between kinesiophobia and a subtest of FCE, and four correlations between psychological factors and RMDQ. No correlation was significant after the Bonferroni correction was applied (P < 0.001). The strength of significant correlations ranged from r = −0.33 to r = 0.25. The multivariate analysis revealed that psychological variables measured in this study could explain 19% of the variance of self-reported disability, with kinesiophobia being the only psychological variable that contributed significantly. The suggested strong relationship between psychological factors and performance-based and self-reported disability could not be confirmed in this study. This may implicate that the relationship between psychological factors and disability in patients with CLBP is not as unambiguous as suggested

Sense and nonsense in sensors

Continuous subcutaneous glucose monitoring (CGM) is a developing technology in the treatment of diabetes mellitus. The first randomised controlled trials on its efficacy have been performed. In several studies, CGM lowered HbA1c in adult patients with suboptimally controlled type 1 diabetes mellitus, when selecting compliant patients who tolerate the device. However, as a preventive tool for hypoglycaemia, CGM has not fulfilled the great expectations. Increasing reimbursement of CGM is expected in the near future, awaiting studies on cost-effectiveness