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Clay Intercalation and its Influence on the Morphology and Transport Properties of EVA/Clay Nanocomposites

Nanocomposite membranes based on poly-(ethylene-co-vinyl acetate) copolymer (18% vinyl acetate content)and two different organomodified clays have been prepared by mechanical mixing using two roll mill method. The morphology of the nanocomposites was investigated using small angle X-ray scattering, scanning electron microscopy, and transmission electron microscopy. The mechanical and thermal studi

A Double Conformationally Restricted Dynamic Supramolecular System for the Substrate-Selective Epoxidation of Olefins-A Comparative Study on the Influence of Preorganization

A double conformationally restricted kinetically labile supramolecular catalytic system, the third generation, was designed and synthesized. We investigated the substrate selectivity of this system by performing competitive pairwise epoxidations of pyridyl-and phenyl-appended olefins. We compared the obtained substrate selectivities to previous less preorganized generations of this system. Five di

Homolytic Cleavage of Molecular Oxygen by Manganese Porphyrins Supported on Ag(111)

Oxygen binding and cleavage are important for both molecular recognition and catalysis. Mn-based porphyrins in particular are used as catalysts for the epoxidation of alkenes, and in this study the homolytic cleavage of O-2 by a surface-supported monolayer of Mn porphyrins on Ag(111) is demonstrated by scanning tunneling microscopy, X-ray absorption, and X-ray photoemission. As deposited, {5,10,15

Gender-dependent levels of hyaluronic acid in cerebrospinal fluid of patients with neurodegenerative dementia.

Numerous reports over the years have described neuroinflammatory events and vascular changes in neurodegenerative diseases such as Alzheimers disease (AD) and dementia with Lewy bodies (DLB). Interestingly, recent reports from other research areas suggest that the inflammatory and vascular processes are influenced by gender. These findings are intriguing from the perspective that women show a high

Fragments of Late Eocene Earth-impacting asteroids linked to disturbance of asteroid belt

The onset of Earth's present icehouse climate in the Late Eocene coincides with astronomical events of enigmatic causation. At similar to 36 Ma ago the 90-100 km large Popigai and Chesapeake Bay impact structures formed within similar to 10-20 ka. Enrichments of He-3 in coeval sediments also indicate high fluxes of interplanetary dust to Earth for 2 Ma. Additionally, several medium-sized impact st

Differentiation of Nerve Fibers Storing CGRP and CGRP Receptors in the Peripheral Trigeminovascular System.

Primary headaches such as migraine are postulated to involve the activation of sensory trigeminal pain neurons that innervate intracranial blood vessels and the dura mater. It is suggested that local activation of these sensory nerves may involve dural mast cells as one factor in local inflammation, causing sensitization of meningeal nociceptors. Immunofluorescence was used to study the detailed d

Pneumatic slug testing in large-diameter wells

There is a need for an alternative method to conventional pumping tests that is logistically easier and faster to use and which can be handled by only one person. The well known slug test fulfils those requirements if the equipment is properly designed. The applicability of small-diameter slug-test equipment using pneumatic initiation in large-diameter wells, up to 12aEuro(3) (0.3 m), is discussed

Activity of serotonin 5-HT1A receptor 'biased agonists' in rat models of Parkinson's disease and l-DOPA-induced dyskinesia.

Serotonin 5-HT1A receptor agonists reduce l-DOPA-induced dyskinesia (LID) in animal models of Parkinson's disease (PD). Here, we compared the effects of novel 5-HT1A receptor 'biased agonists' on LID in hemiparkinsonian rats. F13714 preferentially activates pre-synaptic 5-HT1A autoreceptors. F15599 preferentially activates cortical postsynaptic 5-HT1A heteroreceptors. The partial agonist, tandospi

Gram-positive anaerobic cocci - commensals and opportunistic pathogens.

Among the Gram-positive anaerobic bacteria associated with clinical infections, the Gram-positive anaerobic cocci (GPAC) are the most prominent and account for approximately 25-30% of all isolated anaerobic bacteria from clinical specimens. Still, routine culture and identification of these slowly growing anaerobes to the species level has been limited in the diagnostic laboratory, mainly due to t

Student-centred GP ambassadors: Perceptions of experienced clinical tutors in general practice undergraduate training

Objective. To explore experienced general practitioner (GP) tutor perceptions of a skilled GP tutor of medical students. Design. Interview study based on focus groups. Setting. Twenty GPs experienced in tutoring medical students at primary health care centres in two Swedish regions were interviewed. Method. Four focus-group interviews were analysed using qualitative content analysis. Subjects. Twe

Four-Point Preprandial Self-Monitoring of Blood Glucose for the Assessment of Glycemic Control and Variability in Patients with Type 2 Diabetes Treated with Insulin and Vildagliptin.

The study explored the utility of four-point preprandial glucose self-monitoring to calculate several indices of glycemic control and variability in a study adding the DPP-4 inhibitor vildagliptin to ongoing insulin therapy. This analysis utilized data from a double-blind, randomized, placebo-controlled crossover study in 29 patients with type 2 diabetes treated with vildagliptin or placebo on top

Late Triassic volcanic activity in South-East Asia: New stratigraphical, geochronological and paleontological evidence from the Luang Prabang Basin (Laos)

In South-East Asia, sedimentary basins displaying continental Permian and Triassic deposits have been poorly studied. Among these, the Luang Prabang Basin (North Laos) represents a potential key target to constrain the stratigraphic and structural evolutions of South-East Asia. A combined approach involving sedimentology, palaeontology, geochronology and structural analysis, was thus implemented t

The brain-enriched microRNA miR-124 in plasma predicts neurological outcome after cardiac arrest

Introduction: Early prognostication after successful cardiopulmonary resuscitation is difficult, and there is a need for novel methods to estimate the extent of brain injury and predict outcome. In this study, we evaluated the impact of the cardiac arrest syndrome on the plasma levels of selected tissue-specific microRNAs (miRNAs) and assessed their ability to prognosticate death and neurological

Decay of Polarons and Molecules in a Strongly Polarized Fermi Gas

The ground state of an impurity immersed in a Fermi sea changes from a polaron to a molecule as the interaction strength is increased. We show here that the coupling between these two states is strongly suppressed due to a combination of phase-space effects and Fermi statistics, and that it vanishes much faster than the energy difference between the two states, thereby confirming the first order n

Differential Dynamic Microscopy for Anisotropic Colloidal Dynamics

Differential dynamic microscopy (DDM) is a low-cost, high-throughput technique recently developed for characterizing the isotropic diffusion of spherical colloids using white-light optical microscopy.(1) We develop the theory for applying DDM to probe the dynamics of anisotropic colloidal samples such as various ordered phases, or particles interacting with an external field. The q-dependent dynam

Biomarkers of exposure in Monday morning urine samples as a long-term measure of exposure to aromatic diisocyanates.

PURPOSE: Exposure to diisocyanates is a known occupational hazard. One method for monitoring occupational exposure is by analyzing biomarkers in hydrolyzed urine and plasma. The half-life of the biomarkers in plasma is about 3 weeks, and the urinary elimination is divided into one fast (hours) and one slow phases (weeks). Polymorphism in glutathione S-transferase enzymes (GST) is earlier shown to

Oral contraceptives, reproductive history and risk of colorectal cancer in the European Prospective Investigation into Cancer and Nutrition

BACKGROUND: Oral contraceptive use and reproductive factors may initiate long-term changes to the hormonal milieu and thereby, possibly influence colorectal cancer risk. METHODS: We examined the association of hormonal and reproductive factors with risk of colorectal cancer among 337 802 women in the European Prospective Investigation into Cancer and Nutrition, of whom 1878 developed colorectal ca

Effect of Compressed Offline Foveated Video on Viewing Behavior and Subjective Quality

Offline foveation is a technique to improve the compression efficiency of digitized video. The general idea behind offline foveation is to blur video regions where no or a small number of previewers look without decreasing the subjective quality for later viewers. It relies on the fact that peripheral vision is reduced compared to central vision, and the observation that during free-viewing humans