Enolic iridolactone and other iridoids from Alberta magna

OBJECT: The mechanisms of brain edema formation following spontaneous intracerebral hemorrhage (ICH) are not well understood. In previous studies, no significant edema formation has been found 24 hours after infusion of packed red blood cells (RBCs) into the brain of a rat or pig; however, there is evidence that hemoglobin can be neurotoxic. In this study, the authors reexamined the role of RBCs and hemoglobin in edema formation after ICH. METHODS: The experiments involved infusion of whole blood, packed RBCs, lysed RBCs, rat hemoglobin, or thrombin into the right basal ganglia of Sprague-Dawley rats. The animals were killed at different time points and brain water and ion contents were measured. The results showed that lysed autologous erythrocytes, but not packed erythrocytes, produced marked brain edema 24 hours after infusion and that this edema formation could be mimicked by hemoglobin infusion. Although infusion of packed RBCs did not produce dramatic brain edema during the first 2 days, it did induce a marked increase in brain water content 3 days postinfusion. Edema formation following thrombin infusion peaked at 24 to 48 hours. This is earlier than the peak in edema formation that follows ICH, suggesting that there is a delayed, nonthrombin-mediated, edemogenic component of ICH. CONCLUSIONS: These results demonstrate that RBCs play a potentially important role in delayed edema development after ICH and that RBC lysis and hemoglobin toxicity may be useful targets for therapeutic intervention.     

Smart wheelchair control through a deictic approach

In this paper, the implementation of assistance to the driving of a smart wheelchair through a deictic approach is described. Initially, a state of the art of mobility assistance, interfaces and types of commands for smart wheelchairs is presented. The deictic concept, and more particularly, the approach used for the design of our interface is examined. Then the two functionalities carried out to implement this type of interface, as well as methodology used to control our wheelchair are illustrated. Finally, the usability of this deictic approach for the assistance to the driving of a smart wheelchair is discussed.     

A method for the fabrication of sculptured thin films of periodic arrays of standing nanorods

A simple method for the fabrication of sculptured thin films (STFs) of periodic arrays of high-aspect-ratio (20:1) standing nanorods on silicon substrates is described. It is based on oblique evaporation onto periodically arranged arrays of "mini-rod" topography using a rotating sample stage. Recently, it has been shown that these nanostructures can be prepared on relatively large areas and at low cost, making the method suitable for technological applications.     

Combined use of confocal laser scanning microscopy (CLSM) and Raman microscopy (RM): Investigations on EPS - Matrix

Confocal laser scanning microscopy (CLSM) was applied in combination with Raman microscopy (RM) for the characterization of heterotrophic biofilms. Compared to CLSM, RM allows for a deeper insight into the chemical structure of extracellular polymeric substances (EPS) of the biofilm matrix. A low load of glucose (2 g m⁻² d⁻¹) was applied as substrate to ensure small growth rates of the heterotrophic biofilm. To investigate the influence of hydrodynamic conditions on the chemical composition of EPS, a three funnel flow system was used, wherein biofilms were grown at Reynolds numbers of 1000, 2500 and 4000, respectively.31 and 92 days after inoculation with activated sludge supernatant RM was applied as an additional technique to standard CLSM measurements for a more detailed analysis of the biofilm matrix. Polysaccharide-related Raman bands are in good agreement with the lectin binding analysis from CLSM. For the older biofilm, lectin binding analysis showed no change in the composition of EPS, whereas Raman spectra pointed out a change of EPS composition from predominantly polysaccharides to predominantly (glyco) proteins. For the applied substrate condition no significant influence of the Reynolds number on the chemical properties was observed.     

Experiences from a French-German project - on the integration of pupils in an actual space experiment

The German-French biological experiment AQUARIUS-XENO-PUS which flew on the French Soyuz taxi flight Andromède to the International Space Station ISS was extended by an outreach project. Pupils of class 10 to 12, age 16 to 18 years from Ulm/Germany and Tomblaine-Nancy/France were involved in this space experiment. They recorded swimming behavior of Xenopus laevis tadpoles by video. They used this as the 1gground control for similar observations in microgravity exposed tadpoles on the International Space Station, ISS. The pupils were instructed to perform all experimental steps following the protocol of the video recordings on ISS which were done by the French cosmonaut Claudie Haigneré. After the flight, they evaluated swimming activity of both ground controls and space animals using parameters such as type, velocity and acceleration of swimming, or the distribution patterns of tadpoles within the miniaquaria. The pupil project included theoretical components to introduce them to the field of gravitational biology. Nancy pupils established a homepage (www.xenope.com) about background and aim of their scientific project while Ulm pupils received an extended theoretical and practical education about gravity effects on biological systems, what gravity means for life on Earth, and about hardware used for biological research in Space. A feature of the project was the exchange of ideas between all pupils by internet and meetings which took place in Ulm (June 2001), Nancy (February 2002) and Paris (May 2002). Selected pupils presented the work at international conferences on Life Science Research in Space. The project lasted about 18 months; only 1 of 20 participants left the project after 6 months. - We consider our approach as a successful way to include high school students in space experiments on a cheap cost level and to bring the ideas of gravitational biology into curricula of European schools. The project also showed that personal engagement from the teachers and scientists as well as from the supporting agency staff is a prerequisite for the success of co-operations between school and university.     

Development of a discrete roughness index for longitudinal road profiles

Engineers of off-road equipment, on-road vehicles, pavement and tyres must assess the roughness of a terrain surface for the design of their products. A ubiquitous roughness index is the International Roughness Index (IRI), which quantifies the roughness of a section of road based on the average suspension travel for a particular vehicle at a prescribed speed. The Discrete Roughness Index (DRI) developed in this work addresses a fundamental limitation of the IRI. Specifically, the DRI is calculated for each discretely measured location along a terrain surface; furthermore, the DRI is applicable to vehicles travelling at varying speeds and parameters other than the Golden Quarter-Car on which the IRI is based. The development begins with a consistent discretisation of the terrain surface, vehicle response and the IRI. The Fractional Response Coefficient is then developed which serves a fundamental role in the development of the DRI. Finally, the DRI is developed and its properties are discussed through theory and simulation of the ASTM E1926-08 Profile. One important property of the average DRI is that it converges to the IRI as the distance between sampled points becomes smaller, for the particular case when the Golden Quarter-Car model is simulated at 80 kph. The DRI is a more general solution of the roughness estimation problem than the IRI; therefore, the IRI is a proper subset of the DRI in which the DRI is averaged over a section of road.     

By-Product Feeds for Lactating Dairy Cows: Effects of Cottonseed Hulls,Sunflower Hulls,Corrugated Paper,Peanut Hulls,Sugarcane Bagasse,and Whole Cottonseed with Additives of Fat,Sodium Bicarbonate,and Aspergillus oryzae Product on Milk Production

In Experiment 1, Holstein cows (32) fed diets in three 28-day periods were used to evaluate a 3 × 2 × 2 factorial arrangement of fiber sources (sunflower hulls, pelleted cottonseed hulls, and pelleted undelinted cottonseed hulls at 35% of dry matter), fat (0 or 2.5%). and sodium bicarbonate (0 or 1.0%). Sixteen cows also received Aspergillus oryzae product (56.7 g/day) continuously. Sunflower hulls decreased daily intake (19.4 versus 25.1 kg), milk (23.3 versus 26.5 kg), milk protein (2.85 versus 2.95%), and body weight change (?.08 versus .90 kg), but milk fat percent was higher (3.54 versus 3.32%). Sunflower hulls depressed digestibility of dry matter, organic matter, and acid detergent fiber. Added fat reduced milk fat and protein percents. Experiment 2 evaluated fiber sources (20% ground corrugated cardboard boxes, combination of 10% cardboard and 10% peanut hulls, or 30% cottonseed hulls), animal fat (0 or 2.5%), sodium bicarbonate (0 or .75%), and condensed molasses solubles by-product from rum distilling (0 or 10%). Corrugated boxes effected lowest intake (18.0 kg/day), cottonseed hulls highest intake (23.5 kg/day), and combination intermediate (20.2 kg/day). Added fat depressed fat percent. Condensed molasses solubles lowered milk yield but increased milk fat percent (3.76 versus 3.30), molar percent of acetic acid, and ratio of acetic to propionic. In two other experiments whole cottonseed (12.5 or 15% of dry matter) with corn silage, pelleted steam pressure treated sugarcane bagasse, or cottonseed hulls increased milk yield but decreased milk fat percent, especially with pelleted bagasse.     

Interaction between the pore and a fast gate of the cardiac sodium channel

Permeant ions affect a fast gating process observed in human cardiac sodium channels (Townsend, C., H.A. Hartmann, and R. Horn. 1997. J. Gen. Physiol. 110:11-21). Removal of extracellular permeant ions causes a reduction of open probability at positive membrane potentials. These results suggest an intimate relationship between the ion-conducting pore and the gates of the channel. We tested this hypothesis by three sets of manipulations designed to affect the binding of cations within the pore: application of intracellular pore blockers, mutagenesis of residues known to contribute to permeation, and chemical modification of a native cysteine residue (C373) near the extracellular mouth of the pore. The coupling between extracellular permeant ions and this fast gating process is abolished both by pore blockers and by a mutation that severely affects selectivity. A more superficial pore mutation or chemical modification of C373 reduces single channel conductance while preserving both selectivity of the pore and the modulatory effects of extracellular cations. Our results demonstrate a modulatory gating role for a region deep within the pore and suggest that the structure of the permeation pathway is largely preserved when a channel is closed.     

Schrifttumsberichte

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