A new technique for ligating vessels and similar structures that offers more security is described. The aim of the study was to test whether this hypothesis was correct. Six different types of knots, including the one described in this article were compared by a strength-testing study. The knots were tied on a silicon tube through which a constant air flow of 795.10 mmHg of pressure circulated. Tension of 2 kg was then applied to both loose ends of the suture filament (polyglyconate n degrees 1 gauge) for 25 seconds. Then, 15 seconds after the tension was released an overpressure of 2250.31 mmHg was applied to the system. Two computerized pressure sensors were applied to both ends of the tube. The newly described knot reached the highest strangulating force (997.63 mmHg) and had the highest resistance to slippage. From these results, we conclude that the new knot is far more secure for vessel and duct ligature and that it represents a new and useful tool for surgeons in both open and laparoscopic surgery.

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Samples of a 2Mg-Fe (at.%) mixture were produced by high energy ball-milling (HEBM) with ball to powder ratio = 20:1, in an argon gas atmosphere, in 190 ml vials (sample-1) to produce powders and in 300 ml vials (sample-2) to produce plates. Both samples were cold-pressed into preforms. The preforms were then extruded at 300°C at a ram speed of 1mm/min., with the following extrusion ratios: sample-1 at 3/1 to ensure porosity and sample-2 at 5/1 to increase the adhesion of the plates. The resulting bulks from samples 1 and 2 were hydrogenated for 24h in a reactor under 15 bar of H2to produce the Mg2FeH6complex hydride, and at 11 bar of H2to produce both the complex hydride and MgH2hydride. In addition, sample-1 was severely temperature-hydrogen cycled to verify its microstructural stability and the influence of grain size on the sorption properties. XRD patterns showed Mg(hc), Fe(ccc) and Mg2FeH6in both samples, and sample-2 also contained MgH2and MgO (attributed to processing contamination). DSC results demonstrated that the initial desorption temperature of sample-1 was lower than that of sample-2. However, sample-2 showed faster desorption kinetics, presenting a desorption peak about 73°C below that of sample-1. This could be attributed to the activation/catalyst effect of the MgH2hydride. The improvement in sorption properties was attributed mainly to porosity and to the type of employed catalysts.