Dopamine Transporter Imaging in Psychogenic Parkinsonism and Neurodegenerative Parkinsonism with Psychogenic Overlay: A Report of Three Cases

Background: Differentiating psychogenic parkinsonism from neurodegenerative Parkinson's disease (PD) with psychogenic features is a diagnostic challenge. Case report: We report a detailed longitudinal clinical description of three cases presenting with suspected psychogenic parkinsonism. Dopamine transporter single-photon emission computed tomography (DAT-SPECT) was used as a supplemental diagnostic study and influenced clinical management. Discussion: DAT-SPECT quantified the integrity of the striatal dopaminergic system in these cases of clinically uncertain parkinsonism and supported clinical decision-making

REM Sleep Behavior and Motor Findings in Parkinson’s Disease: A Cross-sectional Analysis

Background: Parkinson's disease (PD) represents a major public health challenge that will only grow in our aging population. Understanding the connection between PD and associated prodromal conditions, such as rapid eye movement sleep behavioral disorder (RBD), is critical to identifying prevention strategies. However, the relationship between RBD and severity of motor findings in early PD is unknown. This study aims to examine this relationship. Methods: The study population consisted of 418 PD patients who completed the Movement Disorders Society‐United Parkinson's Disease Rating Scale (MDS‐UPDRS) and rapid eye movement sleep (REM) disorder questionnaires at the baseline visit of the Michael J. Fox's Parkinson's Progression Markers Initiative (PPMI). Cross‐sectional analysis was carried out to assess the association between REM Sleep Behavior Screening Questionnaire score and MDS UPDRS‐3 (motor) score categories. Correlation with a higher score category was described as “worse motor findings”. A score of 5 on the REM disorder questionnaire was defined as predictive of RBD. Results: Out of the 418 PD patients, 113 (27.0%) had RBD. With univariate logistic regression analysis, individuals with scores predictive of RBD were 1.66 times more likely to have worse motor findings (p = 0.028). Even with age, gender, and Geriatric Depression Scale scores taken into account, individuals with scores predictive of RBD were 1.69 times more likely to have worse motor findings (p = 0.025). Discussion: PD patients with RBD symptoms had worse motor findings than those unlikely to have RBD. This association provides further evidence for the relationship between RBD and PD

Holographic conductivity of zero temperature superconductors

Using the recently found by G. Horowitz and M. Roberts (arXiv:0908.3677) numerical model of the ground state of holographic superconductors (at zero temperature), we calculate the conductivity for such models. The universal relation connecting conductivity with the reflection coefficient was used for finding the conductivity by the WKB approach. The dependence of the conductivity on the frequency and charge density is discussed. Numerical calculations confirm the general arguments of (arXiv:0908.3677) in favor of non-zero conductivity even at zero temperature. In addition to the Horowitz-Roberts solution we have found (probably infinite) set of extra solutions which are normalizable and reach the same correct RN-AdS asymptotic at spatial infinity. These extra solutions (which correspond to larger values of the grand canonical potential) lead to effective potentials that also vanish at the horizon and thus correspond to a non-zero conductivity at zero temperature.Comment: 9 pages, 10 figure

Dynamical perturbations and critical phenomena in Gauss-Bonnet-AdS black holes

We investigate the perturbations of charged scalar field in $5$-dimensional Gauss-Bonnet AdS black hole backgrounds. From the perturbation behaviors we obtain the objective picture on how the high curvature influence the spacetime perturbation and the condensation of the scalar hair. The high curvature effects can also be read from the linear response function such as the susceptibility and the correlation length, when the system approaches the critical point. We find that the Gauss-Bonnet term does not affect the critical exponents of the system and they still take the mean-field values.Comment: 13 pages, 5 figures, to appear in Phys. Lett.

Tracking coverage, dropout and multidimensional equity gaps in immunisation systems in West Africa, 2000-2017.

BACKGROUND: Several West African countries are unlikely to achieve the recommended Global Vaccine Action Plan (GVAP) immunisation coverage and dropout targets in a landscape beset with entrenched intra-country equity gaps in immunisation. Our aim was to assess and compare the immunisation coverage, dropout and equity gaps across 15 West African countries between 2000 and 2017. METHODS: We compared Bacille Calmette Guerin (BCG) and the third dose of diphtheria-tetanus-pertussis (DTP3) containing vaccine coverage between 2000 and 2017 using the WHO and Unicef Estimates of National Immunisation Coverage for 15 West African countries. Estimated subregional median and weighted average coverages, and dropout (DTP1-DTP3) were tracked against the GVAP targets of ≥90% coverage (BCG and DTP3), and ≤10% dropouts. Equity gaps in immunisation were assessed using the latest disaggregated national health survey immunisation data. RESULTS: The weighted average subregional BCG coverage was 60.7% in 2000, peaked at 83.2% in 2009 and was 65.7% in 2017. The weighted average DTP3 coverage was 42.3% in 2000, peaked at 70.3% in 2009 and was 61.5% in 2017. As of 2017, 46.7% of countries (7/15) had met the GVAP targets on DTP3 coverage. Average weighted subregional immunisation dropouts consistently reduced from 16.4% in 2000 to 7.4% in 2017, meeting the GVAP target in 2008. In most countries, inequalities in BCG, and DTP3 coverage and dropouts were mainly related to equity gaps of more than 20% points between the wealthiest and the poorest, high coverage regions and low coverage regions, and between children of mothers with at least secondary education and those with no formal education. A child's sex and place of residence (urban or rural) minimally determined equity gaps. CONCLUSIONS: The West African subregion made progress between 2000 and 2017 in ensuring that its children utilised immunisation services, however, wide equity gaps persist

The holographic superconductors in higher-dimensional AdS soliton

We explore the behaviors of the holographic superconductors at zero temperature for a charged scalar field coupled to a Maxwell field in higher-dimensional AdS soliton spacetime via analytical way. In the probe limit, we obtain the critical chemical potentials increase linearly as a total dimension $d$ grows up. We find that the critical exponent for condensation operator is obtained as 1/2 independently of $d$, and the charge density is linearly related to the chemical potential near the critical point. Furthermore, we consider a slightly generalized setup the Einstein-Power-Maxwell field theory, and find that the critical exponent for condensation operator is given as $1/(4-2n)$ in terms of a power parameter $n$ of the Power-Maxwell field, and the charge density is proportional to the chemical potential to the power of $1/(2-n)$.Comment: LaTeX, 16 pages, 5 figures, typos corrected, one reference added, version to appear in European Physical Journal