339 research outputs found
Functional mapping of stimulus colour in human subjects suffering a central visual defect
The multiple maps of the visual field found in the striate and the pre-striate cortex of the macaque exhibit selective responsiveness to different stimulus parameters (Zeki, 1978, 1980). Evidence for such organization in man is derived primarily from selective losses of visual function associated with disturbance of the central pathways. We present data for a single subject, M. W., who has normal achromatic vision but exhibits grossly abnormal responses to coloured and particularly red stumuli ..
Glutathione s-transferase omega in the lung and sputum supernatants of COPD patients
BACKGROUND: The major contribution to oxidant related lung damage in COPD is from the
oxidant/antioxidant imbalance and possibly impaired antioxidant defence. Glutathione (GSH) is one
of the most important antioxidants in human lung and lung secretions, but the mechanisms
participating in its homeostasis are partly unclear. Glutathione-S-transferase omega (GSTO) is a
recently characterized cysteine containing enzyme with the capability to bind and release GSH in
vitro. GSTO has not been investigated in human lung or lung diseases.
METHODS: GSTO1-1 was investigated by immunohistochemistry and Western blot analysis in 72
lung tissue specimens and 40 sputum specimens from non-smokers, smokers and COPD, in
bronchoalveolar lavage fluid and in plasma from healthy non-smokers and smokers. It was also
examined in human monocytes and bronchial epithelial cells and their culture mediums in vitro.
RESULTS: GSTO1-1 was mainly expressed in alveolar macrophages, but it was also found in airway
and alveolar epithelium and in extracellular fluids including sputum supernatants, bronchoalveolar
lavage fluid, plasma and cell culture mediums. The levels of GSTO1-1 were significantly lower in the
sputum supernatants (p = 0.023) and lung homogenates (p = 0.003) of COPD patients than in nonsmokers.
CONCLUSION: GSTO1-1 is abundant in the alveolar macrophages, but it is also present in
extracellular fluids and in airway secretions, the levels being decreased in COPD. The clinical
significance of GSTO1-1 and its role in regulating GSH homeostasis in airway secretions, however,
needs further investigations
Performance analysis of a Cold Asphalt Concrete Binder Course Containing High Calcium Fly Ash Utilizing Waste Material
It has been established that cold bituminous emulsion mixtures (CBEMs) have a comparatively low initial strength in comparison to hot mix asphalt (HMA), however its superior performance with regard to carbon emissions, is a significant driver regarding its manufacture. In this research, high calcium fly ash (HCFA) together with a fluid catalytic cracking catalyst (FCC) - a rich silica-alumina waste material - have been incorporated to develop a new cold asphalt concrete binder course (CACB) bituminous emulsion mixture. HCFA was used as a substitute for traditional limestone filler while FCC was the additive used to activate the HCFA. The mixturesâ performance was assessed using the indirect tensile stiffness modulus test (ITSM), assessment of resistance against permanent deformation, temperature and water sensitivity tests. Surface morphology was tested using a scanning electron microscopy (SEM). A considerable improvement was identified by the ITSM test in addition to a substantial enhancement in rutting resistance, temperature susceptibility and water sensitivity. It was also established that the addition of FCC to CACB mixtures was found to improve early strength as well as long-term strength, rutting resistance, temperature sensitivity and durability
Laboratory Studies to Examine the Properties of a Novel Cold-Asphalt Concrete Binder Course Mixture Containing Binary Blended Cementitious Filler (BBCF)
Conventional hot asphalt mixtures have an impact on global warming and CO2 emissions contributing to debates on environmental issues which have been raised in recent years. As an alternative, cold emulsion asphalt mixtures (CBEMs) provide considerable benefits such as eco-friendliness, energy efficiency and cost effectiveness connected with safety. However, their weak early strength along with the need for longer curing times (usually 2-24 months) and higher moisture susceptibility compared to hot asphalt mixtures, have been cited as obstacles to their wider application. That said, the incorporation of waste materials in CBEM mixtures enhances sustainability by decreasing the amount of industrial waste materials needed and conserving natural resources. A new binary blended cement filler (BBCF) material generated from high calcium fly ash (HCFA) and fluid catalytic cracking catalyst (FC3R) was found to be very effective in providing microstructural integrity with a novel fast-curing cold asphalt concrete for the binder course (CACB) mixture. Laboratory performance tests included the stiffness modulus test by indirect tension to cylindrical samples, wheel-tracking tests and water sensitivity. Regarding environmental issues, a toxicity characteristic leaching procedure (TCLP) test was performed to analyse the leachate from various specimens comprising concentrations of heavy metal. The findings of these tests have demonstrated that CACB performs extremely well compared to traditional hot mixtures. The stiffness modulus of the BBCF treated mixture â 3730 MPa after 3 days â is higher than the traditional hot mixture (100/150 pen). In addition, the BBCF treated mixture offered a superior performance regarding rutting resistance, fatigue resistance and water susceptibility as well as revealing a considerably lower thermal sensitivity. More significantly, the BBCF treated mixture was found comparable to the traditional asphalt concrete binder course after a very short curing time (1 day). Finally, the concentration of heavy metals in the specimens incorporating the BBCF was observed to be less than the regulatory levels determined for hazardous materials and so requirements were satisfied. Consequently, this BBCF treated mixture has significant potential with reference to its application as a binder course in asphalt pavement
Believing in food addiction: helpful or counter-productive for eating behaviour?
Objective: Obesity is often attributed to an addiction to food, and many people believe themselves to be âfood addicts.â However, little is known about how such beliefs may affect dietary control and weight management. The current research examined the impact of experimentally manipulating participants' personal food addiction beliefs on eating behavior. Methods In two studies, female participants (study 1: N â=â64; study 2: N â=â90) completed foodârelated computerized tasks and were given bogus feedback on their performance which indicated that they had high, low, or average food addiction tendencies. Food intake was then assessed in an ad libitum taste test. Dietary concern and time taken to complete the taste test were recorded in study 2. Results: In study 1, participants in the highâaddiction condition consumed fewer calories than those in the lowâaddiction condition, F (1,60)â=â7.61, P â=â0.008, η p2â=â0.11. Study 2 replicated and extended this finding, showing that the effect of the highâaddiction condition on food intake was mediated by increased dietary concern, which reduced the amount of time participants willingly spent exposed to the foods during the taste test, b â=ââ0.06 (0.03), 95% confidence intervalâ=ââ0.13 to â0.01. Conclusions: Believing oneself to be a food addict is associated with shortâterm dietary restriction. The longerâterm effects on weight management now warrant attention
Does alcohol cue inhibitory control training survive a context shift?
Inhibitory control training (ICT) is a novel psychological intervention that aims to improve inhibitory control in response to alcohol-related cues through associative learning. Laboratory studies have demonstrated reductions in alcohol consumption following ICT compared with control/sham training, but it is unclear if these effects are robust to a change of context. In a preregistered study, we examined whether the effects of ICT would survive a context shift from a neutral context to a seminaturalistic bar setting. In a mixed design, 60 heavy drinkers (40 female) were randomly allocated to receive either ICT or control/sham training in a neutral laboratory over 2 sessions. We developed a novel variation of ICT that used multiple stop signals to establish direct stimulusâstop associations. The effects of ICT/control were measured once in the same context and once following a shift to a novel (alcohol-related) context. Our dependent variables were ad libitum alcohol consumption following training, change in inhibitory control processes, and change in alcohol value. ICT did not reduce alcohol consumption in either context compared with the control group. Furthermore, we demonstrated no effects of ICT on inhibitory control processes or alcohol value. Bayesian analyses demonstrated overall support for the null hypotheses. This study failed to find any effects of ICT on alcohol consumption or candidate psychological mechanisms. These findings illustrate the difficulty in training alcohol-inhibition associations and add to a growing body of literature suggesting that ICT holds little evidential value as a psychological intervention for alcohol use disorders
Pattern discrimination in a human subject suffering visual agnosia
Since suffering a stroke some four years ago, H.J.A. has exhibited lack of visual pattern recognition, and CT scans show areas of neuronal damage localized bilaterally in the posterior cerebral cortex (Humphreys & Riddoch, 1984
State and trait influences on attentional bias to food-cues: The role of hunger, expectancy, and self-perceived food addiction
Food-related attentional bias (AB) varies both between individuals (i.e. trait differences) and within individuals (i.e. state differences), as a function of a foodâs momentary incentive value. People with self-perceived food addiction (SPFA) find food particularly rewarding and may therefore demonstrate increased AB to food-related cues, relative to those who do not perceive themselves as food addicts. However, these trait differences may interact with state factors, such as hunger and the perceived availability of food, to differentially affect AB to food-cues. In the current study, female participants (N=120) completed an eye-tracking task to assess AB to chocolate pictures in which the expectancy of receiving chocolate was manipulated on a trial-by-trial basis (0%, 50%, 100%). Participants were randomly allocated such that half completed the task when hungry (hungry condition), and half completed the task following a lunch meal (satiated condition). Participants also indicated the extent to which they perceived themselves to be âfood addictsâ (SPFAs: n=37; Non-addicts: n=53; Undecided: n=28). Consistent with previous findings, there was a significant main effect of chocolate expectancy; food-related AB was greater on 100% and 50% trials, compared to 0% trials. However, there was no effect of hunger condition (hungry vs. satiated) on AB. Contrary to our hypotheses, SPFAs did not show increased AB to food-cues, and this was not moderated by hunger condition or the expectancy information. Exploratory analyses revealed that higher desire-to-eat (DtE) chocolate was associated with increased AB to chocolate pictures. These findings partially support contemporary theoretical models of AB by indicating a key role for state factors (reward expectancy, DtE) in determining AB to food- cues, while a trait factor (SPFA) was not a significant determinant of food AB
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