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Cellular and molecular basis of beta-amyloid precursor protein metabolism.

In molecular neurobiology, perhaps no molecule has been as thoroughly examined as Alzheimer's beta-amyloid precursor protein (betaAPP). In the ten years since the cDNA encoding betaAPP was cloned, the protein has been the subject of unparalleled scrutiny on all levels. From molecular genetics and cellular biology to neuroanatomy and epidemiology, no scientific discipline has been left unexplored -

Fundamental Bounds on Transmission through Periodically Perforated Metal Screens with Experimental Validation

This article presents a study of transmission through arrays of periodic sub-wavelength apertures. Fundamental limitations for this phenomenon are formulated as a sum rule, relating the transmission coefficient over a bandwidth to the static polarizability. The sum rule is rigorously derived for arbitrary periodic apertures in thin screens. By this sum rule we establish a physical bound on the tra

Cerebrospinal fluid tau fragment correlates with tau PET : a candidate biomarker for tangle pathology

To date, there is no validated fluid biomarker for tau pathology in Alzheimer's disease, with contradictory results from studies evaluating the correlation between phosphorylated tau in CSF with tau PET imaging. Tau protein is subjected to proteolytic processing into fragments before being secreted to the CSF. A recent study suggested that tau cleavage after amino acid 368 by asparagine endopeptid

The Menstrual Cycle and Risk of Breast Cancer : A Review

Cyclic hormonal stimulation of the breast tissue plays a significant role in breast carcinogenesis. Current risk factor models do not include direct measures of cycle characteristics although the effects of possible surrogates of cycle activity such as age at menarche and menopause, parity, and nursing time have been investigated. Future risk models should also include menstrual cycle length, regu

Psychometric properties of the external Housing-Related Control Belief Questionnaire among people with Parkinson’s disease

Background: Housing-related control beliefs are associated with aspects of health among older people in general. Research on Parkinson’s disease (PD) focusing on perceptions of the home are rare and instruments capturing perceived aspects of home have seldom been used. Aims: To evaluate psychometric properties of the external Housing-related Control Beliefs Questionnaire (HCQ) among people with PD

Levels of Retinal Amyloid-β Correlate with Levels of Retinal IAPP and Hippocampal Amyloid-β in Neuropathologically Evaluated Individuals

BACKGROUND: Previous studies have used immunohistology to demonstrate Alzheimer's disease (AD) characteristic accumulation of amyloid-β (Aβ) in the retina of AD patients, a finding indicating retina examination as a potential diagnostic tool for AD pathology. OBJECTIVE: To further explore this idea by investigating whether levels of Aβ42 and Aβ40 in retina are associated with corresponding levels

Utopian visions or dystopian prospects for tourism? A perspective article

Purpose: This paper aims to show how continued failure for tourism to address its global impacts is likely to imply the end of tourism as we know it. Design/methodology/approach: This paper is an opinion piece that discusses tourism out of the global situation in spring 2019. Findings: Tourism is about to undermine its own future, largely as a failure of UNWTO and ICAO to address environmental cha

Occupational load as a risk factor for clinically relevant base of thumb osteoarthritis

Objective: It is postulated that increased load from pinch and grasp in occupational tasks increases the risk of thumb carpometacarpal (CMC1) osteoarthritis (OA). We sought to characterise the relationship between doctor-diagnosed CMC1 OA and occupation in a large working population. Methods: We performed a matched case-control study using a Swedish healthcare register. We identified residents age

A multi-criteria decision model for stakeholder management in city logistics

This paper describes the development and application of a multi-criteria decision model to support stakeholder management in city logistics by prioritising among the diversity of stakeholders' goals. The decision model was applied and tested in a longitudinal case study of a city logistics initiative in Sweden with ten stakeholders. The data were collected included semi-structured interviews and s

Population-based studies of atrial fibrillation and ischemic stroke

AbstractBackground: Atrial fibrillation (AF) is a major risk factor for ischemic stroke and the most common cause of cardioembolic stroke. Early detection of AF and AF subjects at high risk for stroke is therefore important. Beyond traditional strong risk factors, such as high age and hypertension, the improvement of risk prediction with existing risk scores, is modest for most other risk markers.

Differences in phase transformation in laser peened and shot peened 304 austenitic steel

Laser Shock Peening (LSP) and Shot Peening (SP) are processes used to mechanically alter the surface properties of metals by inducing a transient high-pressure wave by a laser pulse or by a high-velocity impact of a peening particle. Both processes aim to induce compressive residual stresses near the surface and the level of residual stresses obtained from SP or LSP is similar. When austenitic steLaser Shock Peening (LSP) and Shot Peening (SP) are processes used to mechanically alter the surface properties of metals by inducing a transient high-pressure wave by a laser pulse or by a high-velocity impact of a peening particle. Both processes aim to induce compressive residual stresses near the surface and the level of residual stresses obtained from SP or LSP is similar. When austenitic ste

Extraction and Modification of Macroalgal Polysaccharides for Current and Next-Generation Applications

Marine macroalgal (seaweed) polysaccharides are highly promising for next-generation applications in several industries. However, despite the reported comprehensive potential of these polysaccharides, commercial products are scarce on the market. Seaweed cultivations are increasing in number and production quantity, owing to an elevated global trend of utilization interest in seaweed. The extracti

Gene transfer across species boundaries in bryophytes : evidence from major life cycle stages in Homalothecium lutescens and H. sericeum

Background and Aims: The mosses Homalothecium lutescens and H. sericeum are genetically, morphologically and ecologically differentiated; mixed populations sometimes occur. In sympatric populations, intermediate character states among gametophytes and sporophytes have been observed, suggesting hybridization and introgression in such populations. Methods: We determined genotypes using bi-allelic co

Attitudes towards self-determination in health care : A general population survey in northern Sweden

Background: Today, patient self-determination has become an issue in many western countries due to the widespread availability and use of technology, which makes it possible to prolong life often in spite of severe disability and poor quality of life. Many people fear an overzealous use of modern life-saying procedures which merely serve to prolong the dying process. As a first step towards autono

Occupational exposures and risk of gastric cancer in a population-based case-control study

Gastric cancer trends seem to follow improvements in the environment of blue-collar workers, but the etiological role of occupational exposures in gastric carcinogenesis is scantily investigated. The risk of gastric adenocarcinoma in 10 common occupational industries, and particularly the long-term effects of asbestos, organic solvents, impregnating agents, insecticides, and herbicides, were evalu

Relational reference attribute grammars: Improving continuous model validation

Just like current software systems, conceptual models are characterised by increasing complexity and rate of change. Yet, these models only become useful if they can be continuously evaluated, validated and serialized. To achieve sufficiently low response times for large models, incremental analysis is required. Reference Attribute Grammars (RAGs) offer mechanisms to perform incremental analysis e