A Case Report of Case Report Pursuit by Medical Student

Medical students often seek case reports as vehicles for academic writing opportunities, conference presentation avenues, and residency/fellowship application highlights. Here we review a case where, due to unfortunate circumstances, a student made a unique diagnosis central to proper patient clinical care, wished to write up the case subsequently, but was ultimately excluded from the final work stemming from the patient case. We review the pitfalls that occurred in the process of pursuing publication of an interesting case, the educational value of pursuing case reports for students, the necessity for strong mentorship in this process, and general principles that medical students can follow regarding case report creation to avoid being burned

GMM Estimation of Empirical Growth Models

This paper highlights a problem in using the first-difference GMM panel data estimator cross-country growth regressions. When the time series are persistent, the first-differenced GMM estimator can be poorly behaved, since lagged levels of the series provide only weak instruments for subsequent first-differences. Revisiting the work of Caselli, Esquivel and Lefort (1996), we show that this problem may be serious in practice. We suggest using a more efficient GMM estimator that exploits stationarity restrictions, and this approach is shown to give more reasonable results than first-differenced GMM in our estimation of an empirical growth model.convergence, growth, generalised method of moments, weak instruments.

Cosmic bubble and domain wall instabilities III: The role of oscillons in three-dimensional bubble collisions

We study collisions between pairs of bubbles nucleated in an ambient false vacuum. For the first time, we include the effects of small initial (quantum) fluctuations around the instanton profiles describing the most likely initial bubble profile. Past studies of this problem neglect these fluctuations and work under the assumption that the collisions posess an exact SO(2,1) symmetry. We use three-dimensional lattice simulations to demonstrate that for double-well potentials, small initial perturbations to this symmetry can be amplified as the system evolves. Initially the amplification is well-described by linear perturbation theory around the SO(2,1) background, but the onset of strong nonlinearities amongst the fluctuations quickly leads to a drastic breaking of the original SO(2,1) symmetry and the production of oscillons in the collision region. We explore several single-field models, and we find it is hard to both realize inflation inside of a bubble and produce oscillons in a collision. Finally, we extend our results to a simple two-field model. The additional freedom allowed by the second field allows us to construct viable inflationary models that allow oscillon production in collisions. The breaking of the SO(2,1) symmetry allows for a new class of observational signatures from bubble collisions that do not posess azimuthal symmetry, including the production of gravitational waves which cannot be supported by an SO(2,1) spacetime.Comment: 35 pages + references, 26 figures. Submitted to JCAP. v2: Acknowledgments updates, no other change

Cosmic bubble and domain wall instabilities I: parametric amplification of linear fluctuations

This is the first paper in a series where we study collisions of nucleated bubbles taking into account the effects of small initial (quantum) fluctuations in a fully 3+1-dimensional setting. In this paper, we consider the evolution of linear fluctuations around highly symmetric though inhomogeneous backgrounds. We demonstrate that a large degree of asymmetry develops over time from tiny fluctuations superposed upon planar and SO(2,1) symmetric backgrounds. These fluctuations arise from zero-point vacuum oscillations, so excluding them by enforcing a spatial symmetry is inconsistent in a quantum treatment. We consider the limit of two colliding planar walls, with fluctuation mode functions characterized by the wavenumber transverse to the collision direction and a longitudinal shape along the collision direction $x$, which we solve for. Initially, the fluctuations obey a linear wave equation with a time- and space-dependent mass $m_{eff}(x,t)$. When the walls collide multiple times, $m_{eff}$ oscillates in time. We use Floquet theory to study the fluctuations and generalize techniques familiar from preheating to the case with many coupled degrees of freedom. This inhomogeneous case has bands of unstable transverse wavenumbers $k_\perp$ with exponentially growing mode functions. From the detailed spatial structure of the mode functions in $x$, we identify both broad and narrow parametric resonance generalizations of the homogeneous $m_{eff}(t)$ case of preheating. The unstable $k_\perp$ modes are longitudinally localized, yet can be described as quasiparticles in the Bogoliubov sense. We define an effective occupation number to show they are created in bursts for the case of well-defined collisions in the background. The transverse-longitudinal coupling accompanying nonlinearity radically breaks this localized particle description, with nonseparable 3D modes arising.Comment: 37 pages + references, 20 figures, submitted to JCA

Cosmic bubble and domain wall instabilities II: Fracturing of colliding walls

We study collisions between nearly planar domain walls including the effects of small initial nonplanar fluctuations. These perturbations represent the small fluctuations that must exist in a quantum treatment of the problem. In a previous paper, we demonstrated that at the linear level a subset of these fluctuations experience parametric amplification as a result of their coupling to the planar symmetric background. Here we study the full three-dimensional nonlinear dynamics using lattice simulations, including both the early time regime when the fluctuations are well described by linear perturbation theory as well as the subsequent stage of fully nonlinear evolution. We find that the nonplanar fluctuations have a dramatic effect on the overall evolution of the system. Specifically, once these fluctuations begin to interact nonlinearly the split into a planar symmetric part of the field and the nonplanar fluctuations loses its utility. At this point the colliding domain walls dissolve, with the endpoint of this being the creation of a population of oscillons in the collision region. The original (nearly) planar symmetry has been completely destroyed at this point and an accurate study of the system requires the full three-dimensional simulation.Comment: 23 pages + references, 13 figures. Submitted to JCAP. v2: Acknowledgements updated, no other change

Evaluation of the probiotic Lactobacillus Fermentum for the prevention of mastitis in breastfeeding women: a randomised controlled trial

Mastitis and accompanying pain have been associated with the cessation of breastfeeding.1-3 Mastitis is an inflammatory condition of the breast and may be related to decreased immunity and lowered resistance to infection. 4 Mastitis affects up to one in five breastfeeding women with most episodes occurring in the first 6-8 weeks postpartum.5 Antibiotics are often used in the treatment of mastitis, but have not been popular or proven effective as a preventative agent.6 The WHO has highlighted significant concerns relating to adverse harms of antibiotic use with the production of antibioticresistant strains of disease organisms.7 Increasing research suggests that specific probiotic bacteria possess significant anti-inflammatory properties and supports their potential use as immunomodulatory agents.8 While animal studies have shown promising results in the use of probiotics for preventing mastitis9, their use in human trials has had limited investigation

Judicial independence in transition: Revisiting the determinants of judicial activism in the constitutional courts of post-communist states

This study investigates the relationship between dimensions of judicial independence and judicial review in constitutional courts Central and Eastern Europe and the Former Soviet Union. In part a modified replication of prior works examining the issue, the study uses newly collected data from a panel of ten countries. It examines the relationship of judicial review with: (1) judicial independence (using both measures employed by the prior works, corrected versions of those measures, and measures original to this study); (2) political and social contextual factors; and (3) the receptiveness of post-communist countries to the importation of transplanted legal institutions. Improvements on the conceptualisation of judicial independence, inclusion of the dimensions of receptiveness, and a more appropriate panel of countries enable this study to present a more complete and accurate portrait of constitutional judicature in transition contexts. The results show that while corrections to prior measures of judicial independence improve the results at the margin, the entirely new measures of the concept represent a greater step forward. Several dimensions of judicial independence are positively related to judicial review, as are the measures of countries’ receptiveness to legal transplants. Other key factors positively related to judicial review in transition include legislative fragmentation at the time of each court decision, the scope of rights guarantees in a bill of rights, and popular trust in courts. Presidential power is negatively related to judicial review. The findings further indicate that aside from judicial independence, the prior works do present correct portrayals of most of the contextual influences they investigate

Effect of Obesity and Exercise on the Expression of the Novel Myokines, Myonectin and Fibronectin Type III Domain Containing 5

Metabolic dysfunction in skeletal muscle is a major contributor to the development of type 2 diabetes. Endurance exercise training has long been established as an effective means to directly restore skeletal muscle glucose and lipid uptake and metabolism. However, in addition to the direct effects of skeletal muscle on glucose and lipids, there is renewed interest in the ability of skeletal muscle to coordinate metabolic activity of other tissues, such as adipose tissue and liver. The purpose of this study was to examine the effects of endurance exercise on the expression level of two novel muscle-derived secreted factors, or myokines, Myonectin and Fibronectin type III domain containing 5 (FNDC5), the precursor for Irisin. Methods. We performed immunoblot analysis and quantitative real-time PCR analysis of Myonectin and FNDC5 in the diaphragm muscles of obese Zucker rat (OZR) and lean Zucker rat (LZR) with 9 weeks of aerobic training on a motorized treadmill. Results. We show that myonectin gene expression is increased in the OZR model of obesity and decreases with exercise in both lean and obese Zucker rats. Conversely, myonectin protein concentration was elevated with exercise. Similarly, FNDC5 mRNA levels are significantly higher in the OZR, however exercise training had no effect on the expression level of FNDC5 in either the LZR or OZR. We did not observe any difference in muscle protein content of Irisin with obesity or exercise. Conclusion. Our data shows that exercise training does not increase either FNDC5 or myonectin gene expression, indicating that increased transcriptional regulation of these myokines is not induced by exercise. However, our data also indicates a yet to be explored disconnect between myonectin gene expression and protein content. Further, this report highlights the importance of verifying reference genes when completing gene expression analysis. We found that many commonly used reference genes varied significantly by obesity and/or exercise and would have skewed the results of this study if used to normalize gene expression data. The unstable reference genes include: beta-Actin, beta-2-microglobulin, Non-POU domain containing, octamer-binding, Peptidylprolyl isomerase H, 18S ribosomal RNA, TATA box binding protein and Transferrin receptor