Revascularization of distal arteriopathies: a new approach

The diffuse nature of arterial occlusions in Buerger's disease compromises the effect of revascularization. Nevertheless, the muscle branches are quite often unaffected by the occlusive disease making revascularization of collateral arterial branches a promising alternative to conventional procedures. Revascularization by a short autologous venous graft from the grand anastomotic or gastrocnemius artery can be an alternative technique. Advances in microsurgery have made such revascularizations possible.     

Directional control of rapid arm movements: The role of the kinetic visual feedback system.

Examined how vision of initial, terminal, or complete arm trajectory affected the movement control and accuracy of 6 right-handed volunteers when the amplitude and directional task constraints were varied. Evidence was found for the significant contribution of vision during the initial phase of rapid pointing movements when this phase is under the control of the kinetic channel. Movements having directional requirements were more accurate when vision of the initial portion of the trajectory was available. Times-to-peak acceleration and velocity were shorter and their respective amplitudes were generally higher when vision was available for the 1st 3rd of the trajectory than when it was not. Vision of the entire trajectory did not yield better precision than when vision was available for the initial phase of the movements only. The data support the existence of 2 supportive visual feedback systems. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modelling of ionospheric high-order errors for new generation GNSS

In dual frequency Global Positioning System receivers, the ionospheric propagation delays are commonly estimated and corrected using the “ionosphere free” combinations of pseudo-range observables. With this method, the ionospheric delay is estimated at the first-order proportional to the inverse of the frequency square. However, higher-order terms exist that may be taken into account when precise corrections are required. The second-order term results from the influence of the geomagnetic field on the ionospheric propagation of the signals. The third-order term includes the refractive effects due to the bending of the ray. Contributions of the second- and third-order terms typically amount to values in the centimetre and millimetre ranges, respectively. In a near future, triple-frequency Global Navigation Satellite Systems transmitting high-resolution codes will become available. These systems are expected to provide a noticeable improvement in accuracy. This paper focuses on the Galileo signals as Galileo In-Orbit Validation Element (GIOVE) signals are now available for acquisition. A solution relying on the triple-frequency characteristics of a signal-in-space is investigated with results based on first measurements of GIOVE-A signals. Eventually, a method is described that relies on precise dual-frequency phase measurements to evaluate the second-order ionospheric contribution for Galileo data.     

Fucoxanthin,a Marine-Derived Carotenoid from Brown Seaweeds and Microalgae: A Promising Bioactive Compound for Cancer Therapy

Fucoxanthin is a well-known carotenoid of the xanthophyll family, mainly produced by marine organisms such as the macroalgae of the fucus genus or microalgae such as Phaeodactylum tricornutum. Fucoxanthin has antioxidant and anti-inflammatory properties but also several anticancer effects. Fucoxanthin induces cell growth arrest, apoptosis, and/or autophagy in several cancer cell lines as well as in animal models of cancer. Fucoxanthin treatment leads to the inhibition of metastasis-related migration, invasion, epithelial–mesenchymal transition, and angiogenesis. Fucoxanthin also affects the DNA repair pathways, which could be involved in the resistance phenotype of tumor cells. Moreover, combined treatments of fucoxanthin, or its metabolite fucoxanthinol, with usual anticancer treatments can support conventional therapeutic strategies by reducing drug resistance. This review focuses on the current knowledge of fucoxanthin with its potential anticancer properties, showing that fucoxanthin could be a promising compound for cancer therapy by acting on most of the classical hallmarks of tumor cells.     

Magnetic Imaging of Cyanide‐Bridged Co‐ordination Nanoparticles Grafted on FIB‐Patterned Si Substrates

Prussian blue CsNiCr nanoparticles are used to decorate selected portions of a Si substrate. For successful grafting to take place, the Si surface needs first to be chemically functionalized. Low‐dose focused ion beam patterning on uniformly functionalized surfaces selects those portions that will not participate in the grafting process. Step‐by‐step control is assured by atomic force and high‐resolution scanning electron microscopy, revealing a submonolayer distribution of the grafted nanoparticles. By novel scanning Hall‐probe microscopy, an in‐depth investigation of the magnetic response of the nanoparticles to varying temperature and applied magnetic field is provided. The magnetic images acquired suggest that low‐temperature canted ferromagnetism is found in the grafted nanoparticles, similar to what is observed in the equivalent bulk material.     

Fire protection of wood by different gypsum plasterboards

Cone calorimeter tests were performed on specimens made of pieces of wood and pieces of gypsum plasterboards protecting the wood against the heat. The thermal behaviour of the gypsum plasterboards of different origin was studied by determining the time to onset of charring and the charring rate of wood. The specimens were exposed to a constant heat flux of 50 kW/m². The test results show that the time to onset of charring is more dependent on the board thickness than the area weight of the boards. The charring rate is fairly well predicted both by the board thickness and area weight, the latter being slightly better as a prediction parameter. The mechanical board properties needed in order to fully understand the fire protection from gypsum plasterboards were not studied in this investigation. Copyright © 1999 John Wiley & Sons Ltd.     

Grain-Size Effects on the High-Temperature Oxidation of Modified 304 Austenitic Stainless Steel

The high-temperature oxidation behavior of modified 304 austenitic stainless steels in a water vapor atmosphere was investigated. Samples were prepared by various thermo mechanical treatments to result in different grain sizes in the range 8–30 μm. Similar Σ3 grain boundary fraction was achieved to eliminate any grain-boundary characteristics effect. Samples were oxidized in an air furnace at 700 °C with 20 % water vapor atmosphere. On the fine-grained sample, a uniform Cr₂O₃ layer was formed, which increased the overall oxidation resistance. Whereas on the coarse-grained sample, an additional Fe₂O₃ layer formed on the Cr-rich oxide layer, which resulted in a relatively high oxidation rate. In the fine-grained sample, grain boundaries act as rapid diffusion paths for Cr and provided enough Cr to form Cr₂O₃ oxide on the entire sample surface.