Larger portions make me eat more : awareness of the external factors that influence food intake

There is consistent evidence that the amount of food people consume can be influenced by external factors, such as food portion size or the amount of food others are eating. However research studies to date have suggested that people are generally unaware of the influence that these external factors have on food intake. In the present research we directly tested whether consumers are aware of how external factors can affect their food intake. In Study 1 we re-analysed data from a study in which an effect of portion size on food intake was observed and post-consumption, participants were asked whether they believed portion size had influenced their food intake. In Study 2 participants were asked to indicate whether several different external factors known to increase food intake would be likely to increase, decrease or have no effect on how much they would eat in hypothetical scenarios. In Study 1, a large proportion of participants (56%) believed that their food intake was influenced by portion size. In Study 2, a large proportion of participants accurately identified that external factors known to affect eating behaviour would be likely to increase their food intake: portion size (73%), social influence (40%), food variety (75%), and distraction (59%). Together these results suggest that consumers show awareness of the influence that external factors have on their food intake

Suppression of Implanted MDA-MB 231 Human Breast Cancer Growth in Nude Mice by Dietary Walnut

Walnuts contain components that may slow cancer growth including omega 3 fatty acids, phytosterols, polyphenols, carotenoids, and melatonin. A pilot study was performed to determine whether consumption of walnuts could affect growth of MDA-MB 231 human breast cancers implanted into nude mice. Tumor cells were injected into nude mice that were consuming an AIN-76A diet slightly modified to contain 10% corn oil. After the tumors reached 3 to 5 mm diameter, the diet of one group of mice was changed to include ground walnuts, equivalent to 56 g (2 oz) per day in humans. The tumor growth rate from Day 10, when tumor sizes began to diverge, until the end of the study of the group that consumed walnuts (2.9 ± 1.1 mm3/day; mean ± standard error of the mean) was significantly less (P \u3e 0.05, t-test of the growth rates) than that of the group that did not consume walnuts (14.6 ± 1.3 mm 3 /day). The eicosapentaenoic and docosahexaenoic acid fractions of the livers of the group that consumed walnuts were significantly higher than that of the group that did not consume walnuts. Tumor cell proliferation was decreased, but apoptosis was not altered due to walnut consumption. Further work is merited to investigate applications to cancer in humans

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 “food addicts.” 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  = 64; study 2: N  = 90) completed food‐related 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 high‐addiction condition consumed fewer calories than those in the low‐addiction condition, F (1,60) = 7.61, P  = 0.008, η p2 = 0.11. Study 2 replicated and extended this finding, showing that the effect of the high‐addiction 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  = −0.06 (0.03), 95% confidence interval = −0.13 to −0.01. Conclusions: Believing oneself to be a food addict is associated with short‐term dietary restriction. The longer‐term effects on weight management now warrant attention

Optically guided linear Mach Zehnder atom interferometer

We demonstrate a horizontal, linearly guided Mach Zehnder atom interferometer in an optical waveguide. Intended as a proof-of-principle experiment, the interferometer utilises a Bose-Einstein condensate in the magnetically insensitive |F=1,mF=0> state of Rubidium-87 as an acceleration sensitive test mass. We achieve a modest sensitivity to acceleration of da = 7x10^-4 m/s^2. Our fringe visibility is as high as 38% in this optically guided atom interferometer. We observe a time-of-flight in the waveguide of over half a second, demonstrating the utility of our optical guide for future sensors.Comment: 6 pages, 3 figures. Submitted to Phys. Rev.

Membrane force reception: mechanosensation in GPCRs and tools to address it

To survive, all organisms must detect and respond to mechanical cues in their environment. Cells are subjected to a plethora of mechanical forces, such as hydrostatic pressure, cell-cell contact, stretch, compression, and shear stress. Mechanosensitive membrane proteins have evolved across all life kingdoms to sense and respond to forces in the membrane. Bacterial mechanosensitive ion channels provide a blueprint for understanding the fundamental mechanisms that underpin cellular responses to mechanical signals. Recently, the identification of eukaryotic force transducers, which includes membrane proteins other than channels, has led to the recognition of common structural hallmarks and unified biophysical mechanisms that could potentially link these diverse proteins. Accumulating evidence suggests G protein-coupled receptors (GPCRs) are candidates for pressure sensing in mammals. This review summarises the current knowledge on mechanosensitive GPCRs, describes the tools used to assess their mechanosensitivity, and aims to highlight the key characteristics that link these receptors to established mechanosensors

A Bright Solitonic Matter-Wave Interferometer

We present the first realisation of a solitonic atom interferometer. A Bose-Einstein condensate of $1\times10^4$ atoms of rubidium-85 is loaded into a horizontal optical waveguide. Through the use of a Feshbach resonance, the $s$-wave scattering length of the $^{85}$Rb atoms is tuned to a small negative value. This attractive atomic interaction then balances the inherent matter-wave dispersion, creating a bright solitonic matter wave. A Mach-Zehnder interferometer is constructed by driving Bragg transitions with the use of an optical lattice co-linear with the waveguide. Matter wave propagation and interferometric fringe visibility are compared across a range of $s$-wave scattering values including repulsive, attractive and non-interacting values. The solitonic matter wave is found to significantly increase fringe visibility even compared with a non-interacting cloud.Comment: 6 pages, 4 figure

Direct comparison of a radioiodinated intact chimeric anti-CEA MAb with its F(ab')2 fragment in nude mice bearing different human colon cancer xenografts.

Tumour localisation and tumour to normal tissue ratios of a chimeric anti-carcinoembryonic antigen (CEA) monoclonal antibody (MAb), in intact form and as an F(ab')2 fragment labelled with 125I and 131I, were compared in groups of nude mice bearing four different colon cancer xenografts, T380, Co112 or LoVo, of human origin, or a rat colon cancer transfected with human CEA cDNA, called '3G7'. For each tumour, three to four mice per time point were analysed 6, 12, 24, 48 and 96 h after MAb injection. In the different tumours, maximal localisation of intact MAb was obtained at 24 to 48 h, and of F(ab')2 fragment 12 to 24 h after injection. Among the different tumours, localisation was highest with colon cancer T380, with 64% of the injected dose per gram (% ID/g) for the intact MAb and 57% for its F(ab')2 fragment, while in the three other tumours, maximal localisation ranged from 14 to 22% ID g-1 for the intact MAb and was about 11% for the F(ab')2. Tumour to normal tissue ratios of intact MAb increased rapidly until 24 h after injection and remained stable or showed only a minor increase thereafter. In contrast, for the F(ab')2 fragment, the tumour to normal tissue ratios increased steadily up to 4 days after injection reaching markedly higher values than those obtained with intact MAb. For the four different xenografts, tumour to blood ratios of F(ab')2 were about 2, 3 and 5 to 16 times higher than those of intact antibodies at 12, 24 and 96 h after injection, respectively

Observation of a Modulational Instability in Bose-Einstein condensates

We observe the breakup dynamics of an elongated cloud of condensed $^{85}$Rb atoms placed in an optical waveguide. The number of localized spatial components observed in the breakup is compared with the number of solitons predicted by a plane-wave stability analysis of the nonpolynomial nonlinear Schr\"odinger equation, an effective one-dimensional approximation of the Gross-Pitaevskii equation for cigar-shaped condensates. It is shown that the numbers predicted from the fastest growing sidebands are consistent with the experimental data, suggesting that modulational instability is the key underlying physical mechanism driving the breakup.Comment: 6 pages, 5 figure