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Memory aging and brain maintenance

Episodic memory and working memory decline with advancing age. Nevertheless, large-scale population-based studies document well-preserved memory functioning in some older individuals. The influential 'reserve' notion holds that individual differences in brain characteristics or in the manner people process tasks allow some individuals to cope better than others with brain pathology and hence show

On the Use of GLS Demeaning in Panel Unit Root Testing

One of the most well-known facts about unit root testing in time series is that the Dickey--Fuller (DF) test based on OLS demeaned data suffers from low power, and that the use of GLS demeaning can lead to substantial power gains. Of course, this development has not gone unnoticed in the panel unit root literature. However, while the potential of using GLS demeaning is widely recognized, oddly eno

Event structure and double helicity asymmetry in jet production from polarized p plus p collisions at root s=200 GeV

We report on the event structure and double helicity asymmetry (A(LL)) of jet production in longitudinally polarized p + p collisions at root s = 200 GeV. Photons and charged particles were measured by the PHENIX experiment at midrapidity vertical bar eta vertical bar < 0.35 with the requirement of a high-momentum (> 2 GeV/c) photon in the event. Event structure, such as multiplicity, p(T) density

Intravenous boluses of fentanyl, 1 μg kg-1, and remifentanil, 0.5 μg kg-1, give similar maximum ventilatory depression in awake volunteers.

BACKGROUND: /st>The relative respiratory effects of fentanyl and remifentanil, administered as i.v. bolus, have not previously been studied. We determined what remifentanil bolus dose gave the same maximum depression of ventilation as 1 µg kg(-1) of fentanyl. METHODS: /st>Twelve healthy volunteers rebreathed in a system designed to dampen variations in end-tidal carbon dioxide tension so that me

High-risk HPV and survival in patients with oral and oropharyngeal squamous cell carcinoma - 5-year follow up of a population-based study.

Abstract Conclusion: No statistically significant 5-year survival difference was seen in patients with oral and oropharyngeal squamous cell carcinoma (OOPSCC) between high-risk HPV-positive and -negative groups in this population-based study. Objectives: To see if the formerly observed higher risk for recurrence or second primary tumour (SPT) in high-risk HPV-positive patients with OOPSCC correspo

Changes in climate and weather extremes in the 21st century

Climate and weather extremes are sporadically recurring events that may have major local or regional impacts on the society and the environment. These events are typically related to unusually high or low temperature, prolonged dry or wet conditions, heavy precipitation, or extreme winds. Extreme events are part of the overall climate and weather alongside average conditions and variability, and t

Chemical and bioassay characterisation of nitrogen availability in biochar produced from dairy manure and biosolids

Biochar is charcoal made from waste biomass and intended to be added to soil to improve soil function and reduce emissions from the biomass caused by natural degradation to CO2. Nitrogen (N) forms in biochar can be complex and their lability likely to be influenced by pyrolysis temperature which, together with the nature of carbon (C), will influence N mineralisation or immobilisation. These compl

Use of snus and acute myocardial infarction: pooled analysis of eight prospective observational studies

The use of snus (also referred to as Scandinavian or Swedish moist smokeless tobacco), which is common in Sweden and increasing elsewhere, is receiving increasing attention since considered a tobacco smoke "potential reduction exposure product". Snus delivers a high dose of nicotine with possible hemodynamic effects, but its impact on cardiovascular morbidity and mortality is uncertain. The aim of

Photon-echo quantum memory in solid state systems

Many applications of quantum communication crucially depend oil reversible transfer of quantum states between light and matter Motivated by rapid recent developments in theory and experiment, we review research related to quantum memory based oil a photon-echo approach in solid state material with emphasis on use in a quantum repeater After introducing quantum communication, the quantum repeater c

Bandpass Filtering of DNA Elastic Modes Using Confinement and Tension

During a variety of biological and technological processes, biopolymers are simultaneously subject to both confinement and external forces. Although significant efforts have gone into understanding the physics of polymers that are only confined, or only under tension, little work has been done to explore the effects of the interplay of force and confinement. Here, we study the combined effects of

Cloud and boundary layer interactions over the Arctic sea ice in late summer

Observations from the Arctic Summer Cloud Ocean Study (ASCOS), in the central Arctic sea-ice pack in late summer 2008, provide a detailed view of cloud-atmosphere-surface interactions and vertical mixing processes over the sea-ice environment. Measurements from a suite of ground-based remote sensors, near-surface meteorological and aerosol instruments, and profiles from radiosondes and a helicopte

Exploring alternate states and oligomerization preferences of coiled-coils by de novo structure modeling

Homomeric coiled-coils can self-assemble into a wide range of structural states with different helix topologies and oligomeric states. In this study, we have combined de novo structure modeling with stability calculations to simultaneously predict structure and oligomeric states of homomeric coiled-coils. For dimers an asymmetric modeling protocol was developed. Modeling without symmetry constrain

Manoeuvring the middle ground: Social mobility and the renegotiation of gender and family obligations among Chinese Singaporeans

The article examines Singaporeans' experiences of upward social mobility and how traditional gender roles within the family are renegotiated and reinterpreted in Singapore. When the former British colony gained independence in 1965 its post-colonial government embarked on an ambitious modernization programme, under which villages were demolished and residents relocated to new high-rise estates, fa

Weak antilocalization and electron-electron interaction in coupled multiple-channel transport in a Bi2Se3 thin film.

The electron transport properties of a topological insulator Bi2Se3 thin film are studied in Hall-bar geometry. The film with a thickness of 10 nm is grown by van der Waals epitaxy on fluorophlogopite mica and Hall-bar devices are fabricated from the as-grown film directly on the mica substrate. Weak antilocalization and electron-electron interaction effects are observed and analyzed at low temper

Enacting entrepreneurship research in a pioneering, provocative and participative way: on the work of Bengt Johannisson

Bengt Johannisson received the International Award for Entrepreneurship and Small Business Research in 2008. In this essay we present and evaluate his work over the last four decades in three of its dimensions: pioneering, provocative and participative. While his research interests and themes range widely, early on he resisted the individualization of entrepreneurship studies and instead emphasize

General Conception of Polar Diagrams for the Evaluation of the Potential Machinability of Workpiece Materials

This article presents a polar diagram method developed for describing and evaluating the potential machinability of different workpiece materials. The potential machinability is examined in terms of five critical properties of the workpiece material. Two groups of materials, a group of common steel grades and the other a group of stainless steels, were examined in detail, their polar diagrams illu

The Sensing of Environmental Stimuli by Follicular Dendritic Cells Promotes Immunoglobulin A Generation in the Gut

In the Peyer's patches (PPs), germinal centers (GCs) are chronically induced by bacteria and are the major sites for generation of gut immunoglobulin A (IgA) immune responses. Whether follicular dendritic cells (FDCs) within the GCs directly contribute to the IgA production in PPs is unknown. We showed here that direct stimulation of FDCs by bacterial products and retinoic acid synergistically enh