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On 16 March 2018, a nursing home notified a possible acute gastroenteritis outbreak that affected 11 people. Descriptive and case–control studies and analysis of clinical and environmental samples were carried out to determine the characteristics of the outbreak, its aetiology, the transmission mechanism and the causal food. The extent of the outbreak in and outside the nursing home was determined and the staff factors influencing propagation were studied by multivariate analysis. A turkey dinner on March 14 was associated with the outbreak (OR 4.22, 95% CI 1.11–16.01). Norovirus genogroups I and II were identified in stool samples. The attack rates in residents, staff and household contacts of staff were 23.49%, 46.22% and 22.87%, respectively. Care assistants and cleaning staff were the staff most frequently affected. Cohabitation with an affected care assistant was the most important factor in the occurrence of cases in the home (adjusted OR 6.37, 95% CI 1.13–36.02). Our results show that staff in close contact with residents and their household contacts had a higher risk of infection during the norovirus outbreak.
We have observed 12 interacting galaxies using the Fabry-Perot interferometer GHαFaS (Galaxy Hα Fabry-Perot system) on the 4.2m William Herschel Telescope (La Palma). We have extracted the physical properties (sizes, Hα luminosity and velocity dispersion) of 236 HII regions for the full sample of interacting galaxies. We have derived the physical properties of 664 HII regions for a sample of 28 isolated galaxies observed with the same instrument in order to compare both populations of HII regions, finding that there are brighter and denser star forming regions in the interacting galaxies compared with the isolated galaxies sample.
In the context of assessing the impact of management and environmental factors on animal health, behaviour or performance it has become increasingly important to conduct (epidemiological) studies in the field. Hence, the number of investigated farms per study is considerably high so that numerous observers are needed for investigation. In order to maintain the quality and validity of study results calibration meetings where observers are trained and the current level of agreement is assessed have to be conducted to minimise the observer effect. When study animals were rated independently by the same observers by a categorical variable the exclusion test can be performed to identify disagreeing observers. This statistical test compares for each variable and each observer the observer-specific agreement with the overall agreement among all observers based on kappa coefficients. It accounts for two major challenges, namely the absence of a gold-standard observer and different data type comprising ordinal, nominal and binary data. The presented methods are applied on a reliability study to assess the agreement among eight observers rating welfare parameters of laying hens. The degree to which the observers agreed depended on the investigated item (global weighted kappa coefficients: 0.37 to 0.94). The proposed method and graphical description served to assess the direction and degree to which an observer deviates from the others. It is suggested to further improve studies with numerous observers by conducting calibration meetings and accounting for observer bias.
A comprehensive and rather complete study for the synthesis of Bismuth thin-films using physical vapor deposition (PVD) techniques aimed at identifying key features of their crystallographic structure and morphology/topography, as a function of the synthesis method is presented. These films were deposited on oxidized and non-oxidized polished silicon substrates, glass-plates and polyimide flexible films, by thermal evaporation (resistive boat and e-beam) DC- and RF-magnetron assisted sputtering, and pulsed laser (ablation) deposition (PLD). The synthesis was performed controlling the main deposition parameters of these methods.
XRD-spectra conclusively indicate that the films can be preferentially oriented along the  or  Bi-structure’s directions, depending on the source-to- substrate (STS)-distance, sputtering power, substrate’s temperature and PLD ion’s kinetic energy. It is also concluded that a relatively short STS-distance results in a rather polycrystalline structure, near independent to the used sputtering power.
Bismuth iron oxide BFO films were produced by the pulsed laser deposition technique. These films are a mixture of BiFeO3 ferroelectrical and Bi25FeO40 piezoelectrical phases. The ferroelectrical domain structure of these films was studied via contact resonance piezoresponse force microscopy (CR-PFM) and resonance tracking PFM (RT-PFM). The proportions of area of these BFO phases were derived from the PFM images. The ferroelectrical domain size corresponds to the size of the BiFeO3 crystals. The CR-PFM and RT-PFM techniques allowed us to be able to distinguish between the ferroelectric domains and the piezoelectric regions existing in the polycrystalline films.
To evaluate the nutritional profile of a lunch offered and consumed in a university canteen in Belgium.
The qualitative and quantitative content of 4365 meals theoretically available and 330 meals consumed was recorded during five weekdays spread over three weeks. Meal combinations were evaluated using a scoring system based on recommendations for Na content, energy from fat, and fruit and vegetable portions.
University canteen in Belgium.
Only a 5 % of the meal combinations available and consumed complied with the three basic dietary recommendations for a hot lunch. The nutritional profile of the meals consumed was in line with that of the meals available.
Our results show how the nutritional profile of what is eaten is largely determined by what is offered. To ensure overall compliance with dietary recommendations, considerable changes on the supply side, i.e. an increase in fruit and vegetable portions and a reduction in salt and fat of the lunch, are needed first in our setting. Our assessment provides baseline data to pilot a nutrient profiling intervention and shows how a nutrient profiling system can be used for meal evaluation purposes.
We report theoretical and experimental observation of photoexcitated hole spin selection in GaAs/GaAlAs n-i-n in resonant tunneling diodes. When subjected to magnetic and electric parallel fields, the spin splitted hole levels leads to several peak structure in the transmissivity. These experimental results are interpreted as an evidence of tunneling transport through spin polarized hole levels of non-magnetic diodes.
This chapter is dedicated to the evaluation of optical interconnects between electronic processors in multiprocessor systems. Each processor is fully electronic except for the incorporation of a number of photodetectors and optical signal transmitters (e.g., laser diodes, light emitting diodes (LEDs) or optical modulators).
The motivation for this analysis stems from fundamental advantages of optics as well as those of electronics. While electrons are charged fermions, subject to strong mutual interactions and strong reactions to other charged particles, photons are neutral bosons, virtually unaffected by mutual interactions and Coulomb forces. Thus, unlike electrons, multiple beams of photons can cross paths without significant interference. This property allows holographic interconnects to achieve a 3-D (three-dimensional) connection density with only 2-D optical elements. Similarly, photons can propagate through transparent materials without appreciable attenuation or power dissipation. Thus, neglecting speed of light delays, the speed of an optical link is limited only by the switching speed and capacitance of the transmitters and detectors. (For a 10 cm connection length, and a 50° hologram deflection angle, the speed-of-light delay is 0.5 ns.) Hence, the speed and power requirements of an optical interconnect are independent of the connection length. Since electrical very large scale integration (VLSI) connections have a switching energy directly proportional to the line length and an RC delay that grows quadratically with line length, for long enough communication links, optical connections will dissipate less power and provide faster data rate communication.
Since the discovery of high critical temperature superconducting oxides, an important factor potentially limiting their technological application has been the typically low value of the critical current density that they can carry. Here are presented the results of a transmission electron microscopy study of sintered YBa2Cu3O7−x aimed primarily at the characterization of those elements of the microstructure responsible for the poor current-carrying capacity in the superconducting state. The observations are further discussed in relation both to the flux pinning characteristics required and to the prospect for controlling the microstructure in order to optimize the properties of this material for technological development.
Among powder diffractionists, there is a concern about establishing criteria for testing existing and new computer methods for searching the Powder Diffraction File (PDF) data base. A large number of papers on this subject have been presented at recent Denver Conferences and at other meetings, such as the American Crystallographic Association.
The PDF now exceeds 42,000 patterns, with an average of about thirty lines per pattern. Thus, it contains approximately 2.5 million numerical values. At its current rate of growth, the PDF will double in less than twenty years.
The concentration of cortisol (F) has been found to decrease only to a limited extent in intact brain tissue maintained at ambient temperature after death, and the decrease is mainly accounted for as 20-dihydrocortisols (DHF). The sum of F and DHF has therefore been estimated in samples of frontal cortex removed from human cadaver brains collected at necropsy, and taken as a measure of the concentration of cortisol at death. Corticosterone concentration was also estimated. The concentration of cortisol in the cerebral cortex of physically healthy individuals who had committed suicide was consistently as low or lower than in the cortex of control patients who had died suddenly without antecedent severe illness. It is concluded therefore that neither the presumed severe emotional stress preceding suicide nor depressive illness itself is associated with high levels of cortisol in the cerebral cortex. On the other hand, it was found that the cerebral cortical concentration of cortisol in patients who had died from stressful somatic diseases was raised and that the increase was roughly related to the likely degree and duration of the physical stress endured by the patients. There was some indication that the ratio of cortisol (F+DHF) to corticosterone may be lower in the cerebral cortex of suicides than in that of controls.
The results from a small series of persons suffering from alcoholism suggested that the amounts of water and electrolytes in their brains (obtained post mortem) differed from those of control and depressed individuals (Shaw, Frizel, Camps and White, 1969). Since publishing this work we have analysed brain tissue from a further series of alcoholic subjects, and in this paper we compare these findings with the original data from control and depressed groups.
One of the hypotheses advanced to explain the processes underlying severe depression postulates a change in brain function due to an alteration in the distribution of cations across the neuronal membranes (Shaw and Coppen, 1966; Shaw, 1966). Electrophysiological evidence of abnormal function of pathways in the nervous system in depression has been obtained by the study of evoked cortical potentials (Shagass and Schwartz, 1966), but evidence of derangement in the distribution of cations between the cells and extracellular space has come only from “whole body” studies (Coppen and Shaw, 1963; Coppen, Shaw, Malleson and Costain, 1966; Shaw and Coppen, 1966).
There is growing evidence of a connection between the metabolism of monoamines and severe depressive illness, but the exact role of these substances in affective disorders has yet to be defined. We know that reserpine depletes the brain of monoamines and that a proportion of patients treated with this compound develop a depressive illness. Conversely a number of compounds which raise the levels of amines in the brain by blocking the enzyme monoamine oxidase have been used in antidepressant therapy. The knowledge that loss of amines may be associated with depression, and that their replenishment in the brain may induce recovery, immediately leads to the question as to which of the biogenic amines is responsible for the affective changes. Pollin, Cardon and Kety (1961) observed the effect of giving various amino acids together with a monoamine oxidase inhibitor (M.A.O.I.) to patients suffering from chronic schizophrenia. They found that only tryptophan, the precursor of the monoamine 5-hydroxytryptamine (5HT), produced an elevation of mood. On the basis of their results, Coppen, Shaw and Farrell (1963) treated a number of patients suffering from severe depressive illness with M.A.O.I. and half of this group also received an oral dose of a suspension of D L-tryptophan (214 mg./kg. body weight) for one week. The patients taking tryptophan and M.A.O.I. recovered more rapidly than those receiving M.A.O.I. alone both while they were on tryptophan and also subsequently. One explanation for these findings was that the combination of M.A.O.I. and tryptophan increased the amount of amines derived from tryptophan in the brain, and that it was this which was responsible for the therapeutic effect. If this were so, then there were several possibilities. The first was that the level of 5HT in the brain was low in depression and the combination of amine precursor and enzyme inhibitor brought it back to normal. Alternatively it may be that recovery occurred as a result of the presence of abnormally large quantities of 5HT in the central nervous system or even following the production of tryptamine, another amine derived from tryptophan.
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