Learned Fear of Gastrointestinal Sensations in Healthy Adults

in Clinical Gastroenterology and Hepatology (2016), 14(11), 155215582

Background & Aims Gastrointestinal symptom-specific fear and anxiety are important determinants of gastrointestinal symptom perception. We studied learning of fear toward innocuous gastrointestinal ... [more ▼]

Background & Aims Gastrointestinal symptom-specific fear and anxiety are important determinants of gastrointestinal symptom perception. We studied learning of fear toward innocuous gastrointestinal sensations as a putative mechanism in the development of gastrointestinal symptom-specific fear and anxiety. Methods Fifty-two healthy subjects (26 women) received 2 types of esophageal balloon distention at a perceptible but nonpainful intensity (conditioned stimulus [CS], the innocuous sensation) and at a painful intensity (unconditioned stimulus [US]). Subjects were assigned randomly to 1 of 2 groups. During the learning phase, the innocuous CS preceded the painful US in the experimental group (n = 26). In the control group (n = 26), on the contrary, the US never followed the CS directly. During a subsequent extinction phase, both groups received only CS distention—the painful US was no longer administered. Indexes of fear learning toward the innocuous CS distention included the skin conductance response, fear-potentiated startle (measured by the eye-blink electromyogram), and self-reported expectancy of the US. Results During the learning phase, only the experimental group learned to fear the innocuous gastrointestinal CS, based on the increase in US expectancy (compared with the control group, P = .04), increased skin conductance response (compared with the control group, P = .03), and potentiated startle reflex (compared with the control group, P = .001) in response to the CS. The differences between the experimental and control groups in US expectancy and skin conductance, but not fear-potentiated startle, disappeared during the extinction phase. Conclusions Fear toward innocuous gastrointestinal sensations can be established through associative learning in healthy human beings. This may be an important mechanism in the development of fear of gastrointestinal symptoms, implicated in the pathophysiology of functional gastrointestinal disorders. [less ▲]

Privacy-preserving Friendship-based Recommender Systems

in IEEE Transactions on Dependable and Secure Computing (2016, November)

Privacy-preserving recommender systems have been an active research topic for many years. However, until today, it is still a challenge to design an efficient solution without involving a fully trusted ... [more ▼]

Privacy-preserving recommender systems have been an active research topic for many years. However, until today, it is still a challenge to design an efficient solution without involving a fully trusted third party or multiple semitrusted third parties. The key obstacle is the large underlying user populations (i.e. huge input size) in the systems. In this paper, we revisit the concept of friendship-based recommender systems, proposed by Jeckmans et al. and Tang and Wang. These solutions are very promising because recommendations are computed based on inputs from a very small subset of the overall user population (precisely, a user’s friends and some randomly chosen strangers). We first clarify the single prediction protocol and Top-n protocol by Tang and Wang, by correcting some flaws and improving the efficiency of the single prediction protocol. We then design a decentralized single protocol by getting rid of the semi-honest service provider. In order to validate the designed protocols, we crawl Twitter and construct two datasets (FMT and 10-FMT) which are equipped with auxiliary friendship information. Based on 10-FMT and MovieLens 100k dataset with simulated friendships, we show that even if our protocols use a very small subset of the datasets, their accuracy can still be equal to or better than some baseline algorithm. Based on these datasets, we further demonstrate that the outputs of our protocols leak very small amount of information of the inputs, and the leakage decreases when the input size increases. We finally show that he single prediction protocol is quite efficient but the Top-n is not. However, we observe that the efficiency of the Top-n protocol can be dramatically improved if we slightly relax the desired security guarantee. [less ▲]

Taking a Look at the Utilisation of Function Models in Interdisciplinary Design: Insights From Ten Engineering Companies

in Research in Engineering Design (2016)

Interdisciplinary system development requires the integration of diverse expertise to combine different engineering technologies and – increasingly often – services, in order to provide users with ... [more ▼]

Interdisciplinary system development requires the integration of diverse expertise to combine different engineering technologies and – increasingly often – services, in order to provide users with expected value and desired functionality in newly developed products. Failure to achieve integration of disciplines can result in design errors posing a direct threat to the users and to the company. Function modelling is expected to provide suitable means for the integration of disciplines early in the development process. However, a plethora of function models can be found within different disciplines or even across and their divergence has proven to hamper shared, cross-disciplinary function modelling in design teams. This article presents research on function modelling in different disciplines in practice. Conducted research comprises empirical studies in ten companies developing mechatronic systems and/or Product-Service Systems in diverse market areas. The studies provide insights into the utilisation of different function models in different disciplines and across, as well as the specific needs and preferences of practicing designers regarding interdisciplinary function modelling. Finally, the obtained insights and their implications for supporting interdisciplinary function modelling are being discussed. Indications are derived which may guide future research endeavours pertaining to the development of support for collaborative, (cross-)disciplinary function modelling. [less ▲]

Concept to predict crack initiation and crack development in fairfaced concrete screeds

in Beushausen, Hans (Ed.) Performance-based approaches for concrete structures (2016, November)

Within a research project of the Laboratory of Solid Structures of the University of Luxemburg, a design concept to predict cracks in various concrete structures will be developed. The current paper ... [more ▼]

Within a research project of the Laboratory of Solid Structures of the University of Luxemburg, a design concept to predict cracks in various concrete structures will be developed. The current paper presents the numerical investigation of crack initiation and crack development of an unreinforced cementitious fairfaced concrete floor. Thereby cracking of concrete is divided into cracking of an early stage and into cracking of a later stage. The present study deals with cracking of an early stage. Taking into account shrinkage and the chronological strength development of the used C20/25 concrete and with the use of the Element Failure Method (EFM) it will be possible to predict, within a Finite Element Analysis, a possible crack path spatial as well as temporal. For this purpose a finite element model, based on a commercial FE-Software is developed. The program is tested on H-shaped concrete specimen with an unfavorable size ratio between surface and volume. Besides, shrinkage on this specimen is hindered so that unplanned restrain forces has to occur. Using an algorithm the finite element program is able to calculate the model gradually for several load steps within a loop. Furthermore the net dependency of the EFM can be excluded by the use of suitable load steps. [less ▲]

Autoévaluation des élèves de l'école primaire en mathématiques

Scientific Conference (2016, November)

Report on the Oberwolfach Workshop "Computations in the Cohomology of Arithmetic Groups"

in Oberwolfach Reports (2016, November)

Explicit calculations play an important role in the theoretical development of the cohomology of groups and its applications. It is becoming more common for such calculations to be derived with the aid of ... [more ▼]

Explicit calculations play an important role in the theoretical development of the cohomology of groups and its applications. It is becoming more common for such calculations to be derived with the aid of a computer. This mini-workshop assembled together experts on a diverse range of computational techniques relevant to calculations in the cohomology of arithmetic groups and applications in algebraic K-theory and number theory with a view to extending the scope of computer aided calculations in this area. [less ▲]

Affective forecasting in an orangutan: predicting the hedonic outcome of novel juice mixes

in Animal Cognition (2016)

Affective forecasting is an ability that allows the prediction of the hedonic outcome of never-before experienced situations, by mentally recombining elements of prior experiences into possible scenarios ... [more ▼]

Affective forecasting is an ability that allows the prediction of the hedonic outcome of never-before experienced situations, by mentally recombining elements of prior experiences into possible scenarios, and pre-experiencing what these might feel like. It has been hypothesised that this ability is uniquely human. For example, given prior experience with the ingredients, but in the absence of direct experience with the mixture, only humans are said to be able to predict that lemonade tastes better with sugar than without it. Non-human animals, on the other hand, are claimed to be confined to predicting—exclusively and inflexibly—the outcome of previously experienced situations. Relying on gustatory stimuli, we devised a non-verbal method for assessing affective forecasting and tested comparatively one Sumatran orangutan and ten human participants. Administered as binary choices, the test required the participants to mentally construct novel juice blends from familiar ingredients and to make hedonic predictions concerning the ensuing mixes. The orangutan’s performance was within the range of that shown by the humans. Both species made consistent choices that reflected independently measured taste preferences for the stimuli. Statistical models fitted to the data confirmed the predictive accuracy of such a relationship. The orangutan, just like humans, thus seems to have been able to make hedonic predictions concerning never-before experienced events. [less ▲]

Using the Empowerment Scale with unemployed people in lifelong learning: Is the tool sound and useful?

in Psychology Research (2016), 6(11), 648-659

Empowerment is a widely used construct in research on social work, mental health and community interventions, but has only been exploited indirectly with the unemployed. But job finding is an important ... [more ▼]

Empowerment is a widely used construct in research on social work, mental health and community interventions, but has only been exploited indirectly with the unemployed. But job finding is an important dimension of empowerment and could be used to test the accuracy of the concept and of its measures. The Making Decisions Empowerment Scale was used with 97 unemployed people who had been jobless for 6 months. Even though the psychometric qualities of the 5 subscales and the total scale were mixed, convergent and discriminant validity with several adaptive and non-adaptive dimensions could be established for the global scale and for the Esteem, Power, Control and, to a lesser degree, the Activism subscales. The results were only marginally better for the 28 items global scale compared to the 9 items Esteem scale. Empowerment could be adequately modelled by using three dimensions: change coping, depression, and chance control of unemployment. Comparing 6 months later those who had found a job with the still unemployed, the 2 groups differed significantly on 2 of the 5 subscales (Activism and Control) though not on the total empowerment scale, nor on the other psychometric scales. The results throw some doubt on the accuracy of an aggregate measure that sums up divergent dimensions. Instead, it is proposed that more specific and individualized constructs be used, at least in unemployment research. [less ▲]

Max-min transmit beamforming via iterative regularization

in 50th Asilomar Conference on Signals, Systems and Computers, November 2016 (2016, November)

This paper introduces an iterative optimization framework to tackle the multi-group multicast Max-Min transmit beamforming problem. In each iteration, the optimization problem is decomposed into four sub ... [more ▼]

This paper introduces an iterative optimization framework to tackle the multi-group multicast Max-Min transmit beamforming problem. In each iteration, the optimization problem is decomposed into four sub-problems, all of which can be solved using computationally efficient algorithms. The advantage of proposed method lies in its ability to handle different types of signal constraints like total power and unimodularity; a feature not exhibited by other techniques. The proposed technique outperforms the well-known semidefinite relaxation method in terms of quality of solutions [less ▲]

La medición de la pobreza y la indigencia en la Argentina

Diverse speeches and writings (2016)