338 research outputs found
The effects of stress on human food choice
Forming a background to this research are the well-established links between stress and disease on the one hand, and dietary composition and disease on the other. Associations between stressful life events and weight gain, and between perceived stress and serum cholesterol, have been observed in the general population. In addition, studies of obese and dieting populations have revealed that the eating behaviour of some individuals is affected by stress. This raises the possibility that one of the mechanisms through which stress might influence health is via an effect on food intake. Stress is widely believed to influence eating behaviour, but the evidence derives largely from clinical observation and anecdotal report. In the small number of studies that have been carried out in this area, the results have been inconclusive. These converging lines of evidence suggest that the influence of stress on food intake and, more specifically, food choice, is well worth studying. A link between stress and fat intake, for example, would be of considerable importance both for understanding the psychobiology of food intake, and for interventions to reduce the prevalence of diseases of Western society such as obesity, diabetes and coronary heart disease. This research aimed to investigate the prevalence and nature of stress-induced changes in eating within the general population, using a variety of methodologies. An initial questionnaire study examined the self reported prevalence of stress induced changes in a population of undergraduate students, looking at the effect of stress on overall intake and also changes in preference for specific foods. It also investigated the possibility that individuals prone to stress-induced changes in eating may be defined by parameters such as gender or dieting status. Results indicated that the majority of the sample believed their eating to be influenced in some way by stress, with reports of increased eating and decreased eating occurring with approximately equal frequencies, although dieters were more likely to report eating more when stressed. Foods reportedly preferred during stress were predominantly snack foods, this was in agreement with reported increases in snacking with stress among the majority of respondents, and was true of hyperphagics and hypophagics alike. Thus the 'dietary role' of a food appeared to be the dominant influence over stress-induced preference in this sample. The stress-eating relationship was examined in the laboratory by manipulating stress and assessing food intake and selection during a single meal. Increased intake of sweet, fatty foods was seen by stressed subjects who were emotional eaters. This group also ate a meal that was highly energy dense compared with unstressed emotional eaters. A longitudinal study of 6 months' duration investigated the stress-eating relationship in the 'real world' environment, by assessing dietary change in department store workers over periods of varying work load. The findings provided tentative support for a general hyperphagic effect of work stress; dietary restraint and emotional eating were not found to influence the stress-eating relationship in this case. Finally structured interviews in a small sample of self-identified 'stress-eaters' provided descriptive data on the nature of the stress-eating relationship. Interviewees consistently referred to their stress-eating tendencies as providing some sort of emotional nourishment rather than fulfilling any increased physiological need for food. The findings from this thesis suggest that during certain types of stress, many individuals are prone to increased snack consumption. Implications are discussed
Relating cell shape and mechanical stress in a spatially disordered epithelium using a vertex-based model
Using a popular vertex-based model to describe a spatially disordered planar
epithelial monolayer, we examine the relationship between cell shape and
mechanical stress at the cell and tissue level. Deriving expressions for stress
tensors starting from an energetic formulation of the model, we show that the
principal axes of stress for an individual cell align with the principal axes
of shape, and we determine the bulk effective tissue pressure when the
monolayer is isotropic at the tissue level. Using simulations for a monolayer
that is not under peripheral stress, we fit parameters of the model to
experimental data for Xenopus embryonic tissue. The model predicts that
mechanical interactions can generate mesoscopic patterns within the monolayer
that exhibit long-range correlations in cell shape. The model also suggests
that the orientation of mechanical and geometric cues for processes such as
cell division are likely to be strongly correlated in real epithelia. Some
limitations of the model in capturing geometric features of Xenopus epithelial
cells are highlighted.Comment: 29 pages, 10 figures, revisio
Comparación del Vitalograph COPD-6® y del Air Smart Spirometer® con la espirometría estándar en el despistaje y el diagnóstico de los pacientes con Enfermedad Pulmonar Obstructiva Crónica (EPOC) en Atención Primaria
La enfermedad pulmonar obstructiva crónica (EPOC) está infradiagnosticada aunque mejora su evo- lución y pronóstico si se trata precozmente y su principal tratamiento es la abstinencia tabáquica. El objetivo principal de este estudio es comparar los espirómetros de campo COPD-6 ® (Vitalograph) y Air Smart Spirometer® con la espirometría estándar en el diagnóstico de la obstrucción bronquial. Los objetivos secundarios son: determinar cuál de los dos espirómetros estudiados es más eficaz y/o eficiente; detectar los falsos positivos que generan y valorar su aportación a la deshabituación tabá- quica.
Participaron 185 pacientes del Centro de Salud Fuensanta con o sin síntomas o signos sugestivos de sufrir EPOC o que ya estaban diagnosticados de la misma. Estos realizaron la prueba con los espirómetros de campo y con el espirómetro estándar, y áquellos que eran fumadores realizaron una cooximetría, repitiéndose la misma a los que en la evolución abandonaron el tabaco. Se recogieron variables sociodemográficas, antropométricas, diagnósticas, del hábito tabáquico y las características espirométricas mediante los espirómetros estudiados y el espirómetro estándar. Por último, se añadió los resultados del cooxímetro y la edad pulmonar estimada del COPD-6 ® (Vitalograph). Para el análisis estadístico se empleó la prueba t-Student y el test ANOVA para la comparación de medias; las variables categóricas se expresaron en porcentaje, y para su comparación se utilizó el test Chi- Cuadrado (c2). Además, se empleó el índice kappa para evaluar la concordancia entre los dispositivos y la espirometría estándar y mediante la regresión logística se calculó su OR (odds ratio). Todos estos cálculos se realizaron utilizando el programa informático IBM SPSS Statistics 26.
De los 185 pacientes, 52,6 % eran varones y 47,6 % mujeres con una edad media de 53,0 años y con un 25,4 % de obesos y un 70,8 % de fumadores. La cifra de corte para el diagnóstico de obstrucción con el COPD-6 ® (Vitalograph) fue FEV1/FEV6 < 75, si lo comparamos con el espirómetro estándar (FEV1/FVC < 70), con un 17,5 % de falsos positivos, un 9 % de falsos negativos, una especificidad de 0,91, una sensibilidad de 0,83, un valor predictivo positivo de 0,83 y un valor predictivo negativo de 0,91. Además, se obtuvo un índice Kappa de 0,735, un área bajo la curva COR de 0,92 y las correlaciones lineales de los valores espirométricos han oscilado entre 0,717 y 0,906. Por otro lado, el punto óptimo para el diagnóstico con el Air Smart Spirometer® fue FEV1/FEV6 < 73, con un 23,8 % de falsos positivos, un 12,3 % de falsos negativos, una sensibilidad de 0,76, una especificidad de 0,88, un valor predictivo positivo de 0,76 y un valor predictivo negativo de 0,88. Además, se obtuvo un índice Kappa de 0,639, un área bajo la curva de COR 0,87 y las correlaciones lineales para el Air Smart Spirometer® de los valores espirométricos han oscilado entre 0,601 y 0,853. Con todo ello, se diagnosticaron 51 nuevos casos de EPOC. Por último, con el COPD-6® (Vitalograph) se calculó que la media de edad pulmonar estimada fue de 64,3 años, mientras que la media de edad biológica era de 53,1 años. Tras unos meses, se objetivó que el 40,5 % de los fumadores disminuyó su tabaquismo y el 18,3 % había dejado de fumar, estos últimos presentaban una media de 21,8 p.p.m. de CO antes cuando eran fumadores y 3,6 unos meses más tarde tras abandono tabáquico.
Las conclusiones del estudio fueron que ambos espirómetros de campo son útiles en una consulta de atención primaria como método de cribado de la EPOC al ser costo-efectivos, teniendo el COPD-6® (Vitalograph) mayor concordancia con el espirómetro estándar.Chronic Obstructive Pulmonary Disease (COPD) is underdiagnosed, although, its evolution and prog- nosis improve if it is treated early. Its main treatment is to eliminate the use of tobacco. The main objective of this study is to compare the office spirometer COPD-6® (Vitalograph) and Air Smart Spirometer® with standard spirometry in the diagnosis of the bronchial obstruction. The secondary objectives are: to determine which of the studied spirometers is more effective and/or efficient; to detect the false positives that they generate and assess their contribution to tobacco cessation.
185 patients from the Fuensanta Health Center with or without symptoms or signs suggestive of suffering COPD or who had already been diagnosed, participated in the study. These patients did the test with the office spirometers and with the standard spirometer. The smoking patients did a CO- oxymetry repeating the same test as those who had abandoned tobacco. Sociodemographic and anthropometric variables, diagnoses, of their smoking habit and spirometry characteristics were picked up using the studied spirometers and the standard spirometer. Finally, the CO-oximetry’s results were added to the estimated pulmonary average from COPD-6® (Vitalograph).
For the statistical analysis, the test t-Student and the test ANOVA were used for the comparison of the averages; the categorical variables were expressed in percentage, and for their comparison test Chi-Square (c2) was used. Additionally, the kappa was used to evaluate the concordance between the devices and the standard spirometry and logistic regression was used to calculate their OR (odds ratio). The calculations were made using the computer program IBM SPSS Statistics 26.
Of the 185 patients, 52.6 % were men and 47.6 % were women with an average age of 53.0 years old of whom 25.4 % were obese and 70.8 % were smokers. The cut figure for the diagnosis of obstruction in the COPD-6® (Vitalograph) is FEV1/FEV6 < 75 if it is compared with the cut figure of the stand- ard spirometry (FEV1/FVC < 70), with 17.5 % of false positives, 9 % of false negatives, a specificity of 0.91, a sensitivity of 0.83, a positive predictive value of 0.83 and a negative predictive value of 0.91. In addition to that, a Kappa index of 0.735 and an under curve area of COR 0.92 were obtained and the COPD-6® (Vitalograph)’s linear correlation of the spirometer’s value oscillated between 0.717 and 0.906. On the other hand, the optimal cutting point for diagnosis with the Air Smart Spi- rometer® is FEV1/FEV6 < 73, with 23.8 % of false positives, 12.3 % of false negatives, a sensitivity of 0.76, a specificity of 0.88, a positive predictive value of 0.76 and a negative predictive value of 0.88. In addition to that, Kappa index 0.639 and under curve area COR 0.87 were obtained and the Air Smart Spirometer®’s linear correlation of the spirometer’s value oscillated between 0.601 and 0.853. Thanks to all of this, 51 new cases of COPD were generated. Finally, with the COPD-6 ® (Vitalograph) the estimated pulmonary average age was calculated as 64.3 years old, meanwhile the biological average age was 53.1 years old. After some months, it was observed that 40.5 % of the smokers decreased their smoking and that 18.3 % had abandoned smoking. These last patients pre- sented and average of 21.8 p.p.m. of CO at the beginning when they were smokers and 3.6 p.p.m. some months later after discontinuing their tobacco use.
The study concludes that either of the office spirometers are useful in a health center office as a COPD screening method because they are cost-effective. The COPD-6® (Vitalograph) has better concord- ance with the standard spirometer
Acquiring L2 sentence comprehension : a longitudinal study of word monitoring in noise
This study investigated the development of second language online auditory processing with ab initio German learners of
Dutch. We assessed the influence of different levels of background noise and different levels of semantic and syntactic target
word predictability on word-monitoring latencies. There was evidence of syntactic, but not lexical-semantic, transfer from the
L1 to the L2 from the onset of L2 learning. An initial stronger adverse effect of noise on syntactic compared to phonological
processing disappeared after two weeks of learning Dutch suggesting a change towards more robust syntactic processing. At
the same time the L2 learners started to exploit semantic constraints predicting upcoming target words. The use of semantic
predictability remained less efficient compared to native speakers until the end of the observation period. The improvement
and the persistent problems in semantic processing we found were independent of noise and rather seem to reflect the need
for more context information to build up online semantic representations in L2 listening.peer-reviewe
Strategies for Site‐Specific Labeling of Receptor Proteins on the Surfaces of Living Cells by Using Genetically Encoded Peptide Tags
Fluorescence microscopy imaging enables receptor proteins to be investigated within their biological context. A key challenge is to site-specifically incorporate reporter moieties into proteins without interfering with biological functions or cellular networks. Small peptide tags offer the opportunity to combine inducible labeling with small tag sizes that avoid receptor perturbation. Herein, we review the current state of live-cell labeling of peptide-tagged cell-surface proteins. Considering their importance as targets in medicinal chemistry, we focus on membrane receptors such as G protein-coupled receptors (GPCRs) and receptor tyrosine kinases (RTKs). We discuss peptide tags that i) are subject to enzyme-mediated modification reactions, ii) guide the complementation of reporter proteins, iii) form coiled-coil complexes, and iv) interact with metal complexes. Given our own contributions in the field, we place emphasis on peptide-templated labeling chemistry.Deutsche Forschungsgemeinschaft
http://dx.doi.org/10.13039/501100001659Leipzig School of Natural SciencesPeer Reviewe
A simple, space constrained NIRIM type reactor for chemical vapour deposition of diamond
In this paper the design of a simple, space constrained chemical vapour deposition reactor for diamond growth is detailed. Based on the design by NIRIM, the reactor is composed of a quartz discharge tube placed within a 2.45 GHz waveguide to create the conditions required for
metastable growth of diamond. Utilising largely off-the-shelf components and a modular design, the reactor allows for easy modification, repair, and cleaning between growth runs. The elements of the reactor design are laid out with the CAD files, parts list, and control files made easily available to enable replication. Finally, the quality of nanocrystalline diamond films produced are studied with SEM and Raman spectroscopy, with the observation of clear
faceting and a large diamond fraction suggesting the design offers deposition of diamond with minimal complexity
Superconducting Diamond on Silicon Nitride for Device Applications
Chemical vapour deposition (CVD) grown nanocrystalline diamond is an
attractive material for the fabrication of devices. For some device
architectures, optimisation of its growth on silicon nitride is essential.
Here, the effects of three pre-growth surface treatments, often employed as
cleaning methods of silicon nitride, were investigated. Such treatments provide
control over the surface charge of the substrate through modification of the
surface functionality, allowing for the optimisation of electrostatic diamond
seeding densities. Zeta potential measurements and X-ray photoelectron
spectroscopy (XPS) were used to analyse the silicon nitride surface following
each treatment. Exposing silicon nitride to an oxygen plasma offered optimal
surface conditions for the electrostatic self-assembly of a hydrogen-terminated
diamond nanoparticle monolayer. The subsequent growth of boron-doped
nanocrystalline diamond thin films on modified silicon nitride substrates under
CVD conditions produced coalesced films for oxygen plasma and solvent
treatments, whilst pin-holing of the diamond film was observed following RCA-1
treatment. The sharpest superconducting transition was observed for diamond
grown on oxygen plasma treated silicon nitride, demonstrating it to be of the
least structural disorder. Modifications to the substrate surface optimise the
seeding and growth processes for the fabrication of diamond on silicon nitride
devices
Estudi de la fiabilitat de la Viquipèdia com a recurs terminològic
En l'àmbit de la traducció especialitzada es considera que la Viquipèdia no és un recurs d'informació especialitzat fiable degut al fet que qualsevol usuari, sigui especialista o no de la matèria, pot redactar un article. En aquest article es vol determinar el grau de fiabilitat de la Viquipèdia com a recurs terminològic especialitzat per als traductors, a partir d'unes tasques que hem definit per tal d'avaluar i valorar el contingut especialitzat.En el ámbito de la traducción especializada se considera que la Wikipedia no es un recurso de información especializada fiable debido a que cualquier usuario, sea especialista o no de la materia, puede redactar una entrada. En este artículo se pretende determinar el grado de fiabilidad de la Wikipedia como recurso terminológico especializado para los traductores, a partir de unas tareas que hemos definido con el fin de evaluar y valorar el contenido especializado.In Translation Studies, it is common to hear that Wikipedia is not a reliable specialized content source due to it can be written either by experts or non-experts. The present work tries to show the reliability of Wikipedia as a terminology source for translators. We have set different tasks to assess and value specialized content
The acceptability of technology-enabled physical activity feedback in cardiac patients and health care professionals
Purpose: Physical activity is a key component of cardiac rehabilitation (CR). Despite the widely reported benefits of CR, uptake in the United Kingdom is still low. Alternative home-based and technology-facilitated delivery models are needed to improve CR uptake and physical activity. This study set out to explore patient and clinician views of personalised, multidimensional physical activity feedback and its potential use within CR. Methods: We developed graphics for the presentation of personalised multidimensional physical activity feedback from data collected through wrist-worn monitors. Thirteen cardiac patients and nine healthcare professionals recruited from South West England wore research grade physical activity monitors for seven days. Participants then attended semi-structured interviews during which personalised physical activity feedback was provided. Interviews were audio-recorded, transcribed, and analysed thematically. Results: Two main themes were derived from the data which covered: 1) the perceived value of multidimensional physical activity feedback, and 2) support needed to facilitate understanding. Within the first theme, participants acknowledged that multidimensional physical activity feedback was useful for monitoring progress, goal setting, and increasing self-awareness of physical activity behaviour among both patients and clinicians. Within theme two, the need for more guidance and support from clinicians to aid patient understanding and reassurance was highlighted, particularly for those with very low physical activity levels. Conclusions: Multidimensional physical activity feedback delivered using a technology-enabled approach was perceived as acceptable among patients and clinicians. This study provides insights into the potential novel use of technology-enabled physical activity feedback to support and expand the delivery of CR.</p
N-acetyl cysteine in the treatment of obsessive compulsive and related disorders: a systematic review
Obsessive compulsive and related disorders are a collection of debilitating psychiatric disorders in which the role of glutamate dysfunction in the underpinning neurobiology is becoming well established. N-acetyl cysteine (NAC) is a glutamate modulator with promising therapeutic effect. This paper presents a systematic review of clinical trials and case reports exploring the use of NAC for these disorders. A further objective was to detail the methodology of current clinical trials being conducted in the area
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