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Circadian Melatonin Rhythm and Excessive Daytime Sleepiness in Parkinson Disease.

IMPORTANCE Diurnal fluctuations of motor and nonmotor symptoms and a high prevalence of sleep-wake disturbances in Parkinson disease (PD) suggest a role of the circadian system in the modulation of these symptoms. However, surprisingly little is known regarding circadian function in PD and whether circadian dysfunction is involved in the development of sleep-wake disturbances in PD. OBJECTIVE To d

Imaging molecular structure through femtosecond photoelectron diffraction on aligned and oriented gas-phase molecules

This paper gives an account of our progress towards performing femtosecond time-resolved photoelectron diffraction on gas-phase molecules in a pump-probe setup combining optical lasers and an X-ray free-electron laser. We present results of two experiments aimed at measuring photoelectron angular distributions of laser-aligned 1-ethynyl-4-fluorobenzene (C8H5F) and dissociating, laser-aligned 1,4-d

Altered Sensory Experience Exacerbates Stable Dendritic Spine and Synapse Loss in a Mouse Model of Huntington's Disease.

A key question in Huntington's disease (HD) is what underlies the early cognitive deficits that precede the motor symptoms and the characteristic neuronal death observed in HD. The mechanisms underlying cognitive symptoms in HD remain unknown. Postmortem HD brain and animal model studies demonstrate pathologies in dendritic spines and abnormal synaptic plasticity before motor symptoms and neurodeg

Microspectroscopy At Beamline 73 MAX-lab

Presentation of some projects at the infrared microspectroscopy experimental station at beamline 73 MAX-lab. Among the subjects are found identification of organic residues in fossil material and examination of the chemistry in an old oak wood wreck.

Arterial stiffness and 24 h ambulatory blood pressure monitoring in young healthy volunteers: The early vascular ageing Aristotle University Thessaloniki Study (EVA-ARIS Study)

Differences in 24 h blood pressure (BP) monitoring parameters such as average 24 h BP, day to night BP ratio and BP variability could have an impact in arterial stiffness. The study hypothesis was that despite similar average BP values in ambulatory blood pressure monitoring subjects with increased 24 h BP variability may have increased arterial stiffness. The study population consisted of 115 con

Drug release mechanisms from Kollicoat SR:Eudragit NE coated pellets

Thin, free films based on Kollicoat SR:Eudragit NE blends were prepared by casting or spraying aqueous dispersions of these polymers, and were thoroughly characterized with respect to their water uptake behavior, water permeability, dry mass loss kinetics, mechanical properties and drug release patterns. A mechanistic mathematical model based on Fick's law of diffusion was used to quantify the exp

Population dynamics of the spruce bark beetle: a long-term study

Bark beetle population dynamics is thought to be primarily driven by bottom-up forces affecting insect performance and host tree resistance. Although there are theoretical predictions and empirical evidences that predation and parasitism may play an important role in driving bark beetle population fluctuations, long-term studies testing the role of both biotic and abiotic controls on population dy

Computationally efficient simulation of extracellular recordings with multielectrode arrays

In this paper we present a novel, computationally and memory efficient way of modeling the spatial dependency of measured spike waveforms in extracellular recordings of neuronal activity. We use compartment models to simulate action potentials in neurons and then apply linear source approximation to calculate the resulting extracellular spike waveform on a three dimensional grid of measurement poi

Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) in adult psychiatry. A 20-year register study.

Nylander L, Holmqvist M, Gustafson L, Gillberg C. Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) in adult psychiatry. A 20-year register study. Nord J Psychiatry 2012;Early Online:1-7 Objective: Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are increasingly recognized in adults. This study aimed to assess trends in diagnostic

Maximal commutative subrings and simplicity of Ore extensions

The aim of this article is to describe necessary and sufficient conditions for simplicity of Ore extension rings, with an emphasis on differential polynomial rings. We show that a differential polynomial ring, R[x;id_R,\delta], is simple if and only if its center is a field and R is \delta-simple. When R is commutative we note that the centralizer of R in R[x;\sigma,\delta] is a maximal commutativ

Phase optimized skeletal mechanisms for engine simulations

Adaptive chemistry is based on the principle that instead of having one comprehensive model describing the entire range of chemical source term space (typically parameters related to temperature, pressure and species concentrations), a set of computationally simpler models are used, each describing a local region (in multidimensional space) or phases (in zero-dimensional space). In this work, an a

Oral iodinated activated charcoal improves lung function in patients with COPD.

The effect of 8 weeks treatment with oral iodinated activated charcoal (IAC) on lung function of patients with moderate chronic obstructive pulmonary disease (COPD) was examined in a double blind randomized placebo controlled parallel group study with 40 patients. In the IAC group, patients showed a statistically significant improvement of FEV1 baseline by 130 ml compared to placebo, corresponding

The added value of hybrid ventilation/perfusion SPECT/CT in patients with stable COPD or apparently healthy smokers. Cancer-suspected CT findings in the lungs are common when hybrid imaging is used

Ventilation/perfusion (V/P) single-photon emission computed tomography (SPECT) is recognized as a diagnostic method with potential beyond the diagnosis of pulmonary embolism. V/P SPECT identifies functional impairment in diseases such as heart failure (HF), pneumonia, and chronic obstructive pulmonary disease (COPD). The development of hybrid SPECT/computed tomography (CT) systems, combining funct

Phenology of two interdependent traits in migratory birds in response to climate change.

In migratory birds, arrival date and hatching date are two key phenological markers that have responded to global warming. A body of knowledge exists relating these traits to evolutionary pressures. In this study, we formalize this knowledge into general mathematical assumptions, and use them in an ecoevolutionary model. In contrast to previous models, this study novelty accounts for both traits-a

Structural insights into aquaporin selectivity and regulation.

Aquaporins have emerged as one of the structurally best-characterized membrane protein families, with fourteen different structures available from a diverse range of organisms. While all aquaporins share the same fold and passive mechanism for water permeation, structural details allow for differences in selectivity and modes of regulation. These details are now the emphasis of aquaporin structura

Development of a novel combined fluorescence and reflectance spectroscopy system for guiding high-grade glioma resections _ Confirmation of capability in lab experiments

Total resection of glioblastoma multiform (GBM), the most common and aggressive malignant brain tumor, is challenging among other things due to difficulty in intraoperative discrimination between normal and residual tumor cells. This project demonstrates the potential of a system based on a combination of autofluorescence and diffuse reflectance spectroscopy to be useful as an intraoperative guidi