Dissolved Silicon and Its Origin in Belgian Beers—A Multivariate Analysis

Beer is a quintessential part of Belgian heritage. We performed a detailed analysis of factors controlling Si content in Belgian beers as a case study to coincide with the 2011 IBiS meeting in Antwerp (Belgium). Beer is one of the richest dietary sources of Si. Three decades of research have yielded evidence of a role for Si in human physiology: it plays an essential role in bone mineral density and reduces the biological availability of aluminium. We analysed 119 Belgian beers: highest dissolved Si concentrations were found in high fermentation, traditionally brewed ales. Concentrations ranged between 214 and 2,071 μmol L^???1. This is probably due to the complexity and length of the brewing procedure: longer, more complicated processing and presence of brewing sediment in the bottle allows more Si to dissolve out of the base products like hop, barley or even rice. As a side effect of fermentation, alcohol content was related to Si content.     

Prevention of Clostridium outgrowth in heated and hermetically sealed meat products by nitrite – a review

This paper discusses several hypotheses regarding the inhibition of Clostridium in cured meat. It focuses on the binding of iron, as there is some evidence that inhibition of Clostridium botulinum outgrowth in nitrite-cured meat products is mainly due to iron binding in such a way that it is no longer available for outgrowth of Clostridium spores. This strong binding also explains the antioxidative properties of nitrite in these products. The binding of iron, in all probability, requires no more than a moderate amount of nitrite which, after binding as nitric oxide to the haem group, is unavailable for reactions leading to N-nitroso compounds either. Other reactions of nitrite, which also could lead to Clostridium inhibition, are not discussed in detail here.     

Stability of sulphadimidine during raw fermented sausage preparation: reaction of sulphadimine with nitrite

 Raw fermented sausage was prepared from a dough to which sulphadimidine (SDM), a drug frequently used in animal husbandry, was added. With the aid of thermospray-mass spectroscopy further evidence was obtained that, during preparation, reactions with nitrite added to the dough resulted in the formation of desamino-SDM and 4-hydroxydesamino-SDM. An indication was obtained that traces of chlorodesamino-SDM were present in the brine, but this observation could not be established. Received: 22 March 1999 / Revised version: 10 May 1999     

Optimal orientation in flows: providing a benchmark for animal movement strategies

Animal movements in air and water can be strongly affected by experienced flow. While various flow-orientation strategies have been proposed and observed, their performance in variable flow conditions remains unclear. We apply control theory to establish a benchmark for time-minimizing (optimal) orientation. We then define optimal orientation for movement in steady flow patterns and, using dynamic wind data, for short-distance mass movements of thrushes (Turdus sp.) and 6000 km non-stop migratory flights by great snipes, Gallinago media. Relative to the optimal benchmark, we assess the efficiency (travel speed) and reliability (success rate) of three generic orientation strategies: full compensation for lateral drift, vector orientation (single-heading movement) and goal orientation (continually heading towards the goal). Optimal orientation is characterized by detours to regions of high flow support, especially when flow speeds approach and exceed the animal''s self-propelled speed. In strong predictable flow (short distance thrush flights), vector orientation adjusted to flow on departure is nearly optimal, whereas for unpredictable flow (inter-continental snipe flights), only goal orientation was near-optimally reliable and efficient. Optimal orientation provides a benchmark for assessing efficiency of responses to complex flow conditions, thereby offering insight into adaptive flow-orientation across taxa in the light of flow strength, predictability and navigation capacity.     

Design of filament-wound circular toroidal hydrogen storage vessels based on non-geodesic fiber trajectories

One of the most important design issues for filament-wound hydrogen storage vessels reflects on the determination of the optimal winding trajectories. The goal of this paper is to determine the optimal fiber paths and the resulting laminated structures for non-geodesically overwound circular toroidal hydrogen storage vessels. With the aid of the continuum theory and the non-geodesic law, the differential equations describing non-geodesic paths on a toroidal surface are given. The general criteria for avoiding fiber-bridging and slippage on a torus are formulated by differential geometry. The relation between the slippage coefficient and the winding angle is obtained to meet stable winding requirements. The initial winding angle and the slippage coefficient of non-geodesics are considered as the design variables, while the minimum shell mass acts as the objective function. The optimal non-geodesic trajectories, corresponding to various relative bending radii, are determined in order to evaluate the effect of non-geodesics on the structural performance of toroids. Results indicate that circular toroidal vessels designed using the present method show better performance than geodesics-based ones, mainly triggered by maximum utilization of the laminate strength. The results also reveal that the structural efficiency of circular toroidal vessels can be significantly improved using non-geodesic winding.     

Non-metropolitan Growth Potential of Western Cape Municipalities

This paper provides a brief overview of the relevant post-2000 South African policy for regional (provincial) spatial development within the context of the quantitative findings of a study conducted on the growth potential of non-metropolitan settlements in the Western Cape. The findings are presented at municipal level. Five indices (social needs, economic, physical environment, infrastructure and institutional) and 69 indicators were used to determine development potential and social needs for the 24 local municipalities and three district management areas in the province. The potential indicators for each index were subjected to a factor analysis to select appropriate core indicators for inclusion in the composite indices. Based on their overall performance in the various indices, the municipalities were classified into three categories??high, medium and low. The study results prioritise areas according to their developmental potential and social needs at municipal level.     

万桥园

<正>序生命之路——致"万桥园"每座园林都有一个故事。它们是诗,在诉说。我们的园林讲述的是生命的故事,人的生命之路。这条路跌宕起伏,忍辱负重,讲述了忧愁河上的众桥。在这座园林中,生命是一条绵延不绝的蜿蜒小路,更恍如一座迷宫。     

‘Green’ synthesis and optical properties of silver–chitosan complexes and nanocomposites

Silver nanoparticles were synthesized in a chitosan biopolymer by an in situ ‘green’ chemical procedure, using d-glucose as the reducing agent. The reaction intermediates (silver–chitosan complexes) as well as the obtained nanocomposites were investigated using transmission electron microscopy, UV–vis, FTIR and photoluminescence spectroscopy. The theoretical analysis of the UV–vis absorption of the Ag–chitosan complexes suggested that the significant contribution to the complex spectrum arises from clusters of silver containing 4–9 atoms. The absorption spectrum of the nanocomposite exhibited a strong surface plasmon resonance band at 406 nm. The photoluminescence behavior of the pure chitosan, the silver–chitosan complexes and the nanocomposites were discussed in terms of morphology and silver weight content.     

Identification of Queen Sex Pheromone Components of the Bumblebee Bombus terrestris

We investigated the origin and chemical composition of the queen sex pheromone of the primitively eusocial bumblebee, Bombus terrestris (Apidae). Physiologically and behaviorally active compounds were identified by coupled gas chromatography electroantennography (GC-EAD), gas chromatography-mass spectrometry (GC-MS), and laboratory behavioral tests. In the behavioral assays, virgin queens frozen previously at −20°C were highly attractive to males. Dummies impregnated with surface and cephalic extracts obtained from virgin queens that had been frozen at −50°C were more attractive to males than odorless dummies. Male mating behavior was stimulated by components of cephalic secretions that are smeared onto the cuticle surface by the queen. Overall, 21 compounds present in surface and cephalic extracts evoked electroantennographic responses in male antennae. These included saturated and unsaturated fatty acids, ethyl- and methyl esters of the fatty acids, heptacosene, 2-nonanone, and geranyl geraniol. A blend of synthetic versions of these compounds elicited typical male mating behavior. Since solvent-impregnated dummies were approached by the males, but did not release copulatory behavior, visual cues may be important in the initial step of stimulating male mating behavior. Close-range olfactory signals are more important for releasing male mating behavior as well as for species recognition. In further behavioral assays, the attractiveness of a frozen virgin queen decreased as the storage time at −20°C increased from 2 hr to 1 d. Therefore, the chemical composition of the sex pheromone may change during freezing as behaviorally active compounds may decompose.     

Bending and optimisation of an inflated braided beam

Two braided inflatable beams have been made that differ in the number of axial fibres that are placed parallel to the length, and in the angle at which the bias fibres are placed. Each beam consists of a silicone rubber bladder, two end caps and a dry carbon fibre braid placed over the silicone bladder. Experimental and theoretical analysis of the beams have been revealed that due to bending, the beams initially deflect in a linear manner like the Euler–Bernoulli beam model predicts. Once the stress in the axial fibres becomes zero, wrinkling occurs resulting in a significant loss of bending stiffness. The two beams that were tested were optimised for minimum deflection at a constant volume of fibres. The stiffest design has the maximum possible amount of fibres in parallel to the beam.