Finding the attractor of anger: Bridging the gap between dynamic concepts and empirical data.

Although it accounts for the prototypical course of emotions, the attractor concept has hardly ever been used empirically. Authors applied Empirical Differential Equations (EDE) to frequent (hourly) anger ratings to find the attractor of anger. The attractor concept, its neurological basis, and EDE are explained. The attractor of anger follows an underdamped oscillator, and is affected by the capacity to inhibit prepotent responses. Anger accelerates less fast when inhibitory control increases. Results stress the internal dynamics of emotions, and help to bridge the gap between concepts from dynamic systems theory and empirical data. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Life cycle energy analysis of a zero-energy house

Most zero-energy concepts focus on a reduction of the non-renewable operational energy use in buildings rather than taking the reduction of their life cycle energy use as a starting point. Nevertheless, the life cycle embodied and end-of-life energy will become more important, especially in buildings with low operational energy. Therefore, the life cycle energy use of a Belgian zero-energy reference house is examined by means of life cycle energy assessment. The influence of design decisions and regulations on the building construction type, the building services, and the performance of the building envelope are investigated. In terms of thermal performance of the building, the results show that the life cycle embodied energy in zero-energy houses with passive or standard thermal performance was not substantially different. From a life cycle energy perspective, passive house requirements are not essential criteria for zero-energy houses in Belgium. On the other hand, large life cycle energy savings were obtained through a proficient selection of all building construction materials and services. For the life cycle embodied energy in building constructions, the best timber frame and masonry houses were equally efficient. Wood pellets and photovoltaic panels were decisive factors in the life cycle embodied energy of building services.

Les concepts <<zéro-énergie>> sont axés pour la plupart sur une réduction de l'utilisation de l'énergie d'exploitation non renouvelable dans les bâtiments plutôt que de prendre la réduction de leur consommation d'énergie sur le cycle de vie comme point de départ. Néanmoins, l'énergie grise sur le cycle de vie et l'énergie de fin de vie vont gagner en importance, en particulier dans les bâtiments nécessitant une faible énergie d'exploitation. La consommation d'énergie sur le cycle de vie d'une maison belge «zéro énergie» de référence est donc étudiée au moyen d'un bilan énergétique du cycle de vie. Sont étudiés l'influence des décisions de conception et de la réglementation sur le type de construction du bâtiment, les services au bâtiment, et les performances de l'enveloppe du bâtiment. En termes de performance thermique du bâtiment, les résultats montrent que l'énergie grise sur le cycle de vie n'était pas fondamentalement différente dans les maisons «zéro énergie» offrant des performances thermiques passives ou standard. Du point de vue de l'énergie du cycle de vie, les exigences d'une maison passive ne sont pas des critères essentiels pour des maisons «zéro énergie» en Belgique. En revanche, d'importantes économies d'énergie sur le cycle de vie ont été obtenues par un choix opéré avec compétence de tous les matériaux de construction et services au bâtiment. S'agissant de l'énergie grise sur le cycle de vie dans la construction de bâtiments, les meilleures maisons, qu'elles aient été à ossature bois ou en maçonnerie, ont été tout aussi performantes. Les granulés de bois et les panneaux photovoltaïques ont été des facteurs décisifs concernant l'énergie grise sur le cycle de vie des services aux bâtiments.

Mots clés: services aux bâtiments, énergie grise, analyse énergétique du cycle de vie, [construction] passive, bâtiments résidentiels, <<zéro-énergie>>     

Speed dependence of crutch force and oxygen uptake: implications for design of comparative trials on orthoses for people with paraplegia

The major defence mechanism in frogs in via the secretion of toxins from their skin. In humans, intoxication may occur when part of the amphibian integument is ingested, as in the form of herbal medicines. Two groups of South African frogs have skin secretions that are potentially lethal to humans and animals. Toads (Bufo and Schismaderma species), the amphibians with which man and his pets most frequently have contact, secrete potent toxins with cardiac glycoside activity. Topical and systemic intoxication, while seen in humans, remains predominantly a veterinary problem. Intoxication by the red-banded rubber frog, which secretes an unidentified cardiotoxin, is far less common. The probable mechanisms of intoxication and management of a poisoned patient are discussed.     

Sediment toxicity of a rapidly biodegrading nonionic surfactant: Comparing the equilibrium partitioning approach with measurements in pore water

The equilibrium partitioning theory (EqP) assumes that the toxicity of nonionic surfactants in sediment can be predicted from water-only toxicity data as long as the effect concentrations are properly normalized for chemical activity. Therefore, in marine sediment toxicity tests with the model alcohol ethoxylate (AE), C12EO8, freely dissolved concentrations were both measured via solid-phase microextraction and predicted using sorption coefficients. In fully equilibrated test systems (including the overlying water), both methods showed that concentrations in the pore water of the spiked sediment layer causing 50% mortality (LC50) to the amphipod Corophium volutator were in the same range as LC50 values for amphipods exposed to AE in seawater only. In the sediment systems, AE concentrations in the pore water remained constant up to 15 days, while concentrations in the water overlying the sediment decreased to less than 1% of initial concentrations within 6 days due to biodegradation. In such disequilibrated test systems, C. volutator survived pore water dissolved concentrations that were above the LC50. Apparently, this burrowing amphipod is able to exploit the low chemical activity in the overlying water as a refuge from sediment exposure.     

Psychologically inspired anticipation and dynamic response for impacts to the head and upper body

We present a psychology-inspired approach for generating a character' s anticipation of and response to an impending head or upper body impact. Protective anticipatory movement is built upon several actions that have been identified in the psychology literature as response mechanisms in monkeys and in humans. These actions are parameterized by a model of the approaching object (the threat) and are defined as procedural rules. We present a hybrid forward and inverse kinematic blending technique to guide the character to the pose that results from these rules while maintaining properties of a balanced posture as well as characteristics of the behavior just prior to the interaction. In our case, these characteristics are determined by a motion capture sequence. We combine our anticipation model with a physically-based dynamic response to produce animations where a character anticipates an impact before collision and reacts to the contact, physically, after the collision. We present a variety of examples including threats that vary in approach direction, size and speed.     

Spatial grouping determines temporal integration.

To make sense out of a continuously changing visual world, people need to integrate features across space and time. Despite more than a century of research, the mechanisms of features integration are still a matter of debate. To examine how temporal and spatial integration interact, the authors measured the amount of temporal fusion (a measure of temporal integration) for different spatial layouts. They found that spatial grouping by proximity and similarity can completely block temporal integration. Computer simulations with a simple neural network capture these findings very well, suggesting that the proposed spatial grouping operations may occur already at an early stage of visual information processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Loss of Microglial Insulin Receptor Leads to Sex-Dependent Metabolic Disorders in Obese Mice

Obesity and type 2 diabetes mellitus (T2DM) are highly prevalent disorders, associated with insulin resistance and chronic inflammation. The brain is key for energy homeostasis and contains many insulin receptors. Microglia, the resident brain immune cells, are known to express insulin receptors (InsR) and to be activated by a hypercaloric environment. The aim of this study was to evaluate whether microglial insulin signaling is involved in the control of systemic energy homeostasis and whether this function is sex-dependent. We generated a microglia-specific knockout of the InsR gene in male and female mice and exposed them to control or obesogenic dietary conditions. Following 10 weeks of diet exposure, we evaluated insulin tolerance, energy metabolism, microglial morphology and phagocytic function, and neuronal populations. Lack of microglial InsR resulted in increased plasma insulin levels and insulin resistance in obese female mice. In the brain, loss of microglial InsR led to a decrease in microglial primary projections in both male and female mice, irrespective of the diet. In addition, in obese male mice lacking microglial InsR the number of proopiomelanocortin neurons was decreased, compared to control diet, while no differences were observed in female mice. Our results demonstrate a sex-dependent effect of microglial InsR-signaling in physiology and obesity, and stress the importance of a heterogeneous approach in the study of diseases such as obesity and T2DM.     

Impact of microalgal feed supplementation on omega-3 fatty acid enrichment of hen eggs

In many Western countries, the average intake of the health beneficial omega-3 long chain polyunsaturated fatty acids (n-3 LC-PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), is below the recommended level, raising interest in food enrichment with n-3 LC-PUFA. To that end, the impact of feed supplementation with EPA rich autotrophic microalgal biomass on n-3 L-PUFA enrichment of eggs was studied. Hens were divided in three groups receiving different diets for 28 days: a standard diet (C) for laying hens, (C) supplemented with 5.0% spray dried Nannochloropsis gaditana, and (C) to which 10.0% of these microalgae were added. Microalgal EPA was hardly accumulated in yolk lipids, but preferentially converted to DHA and deposited in yolk phospholipids. The efficiency of deposition of microalgal n-3 LC-PUFA to eggs was rather low. Switching back to standard feed ensured that the n-3 LC-PUFA level obtained in enriched eggs decreased back to that of the control eggs. Moreover, the colour of egg yolk shifted from yellow to more orange-red, which is presumably due to transfer of microalgal carotenoids to egg yolk. Thus, the use of autotrophic microalgae as supplement for standard feed offers an alternative to current sources for the production of DHA enriched eggs.     

Bioaccumulation of organic chemicals in contaminated soils: evaluation of bioassays with earthworms

Earthworms live in close contact with the soil and can thus be considered representative for the bioavailability of chemicals at contaminated sites. Bioavailability can either be assessed by analyzing earthworms from contaminated locations or by exposing laboratory-reared specimens to soil samples from the field (bioassays). In this study, we investigate the relevance of bioassays by using an extended experimental design (to identify signs of depletion of the bioavailable phase by the earthworms) and by using two species of earthworm (the standard test species Eisenia andrei and the field-relevant Aporrectodea caliginosa). Furthermore, bioassay results are compared to body residues of worms collected from the field site: a heavily polluted polder, amended with dredge spoil. We focused on telodrin, dieldrin, hexachlorobenzene, and eight PCBs. With our bioassay design, it was shown that depletion was unlikely, although more subtle effects could have occurred (e.g., changes in sorption during the experiments). E. andrei is a good choice for bioassays because its body residues correlate well to those in A. caliginosa, as well as to those in the field-collected worms. Nevertheless, E. andrei accumulated slightly more than the other species and appeared to be more sensitive to the conditions in soil from one of our sites.