Transvenous cholangiography and percutaneous transhepatic fine needle cholangiography (author's transl)

The comparison of transvenous cholangiography (TVC) in 82 patients with percutaneous transhepatic fine needle cholangiography (PTFC) in 84 patients showed that TVC must be considered obsolete due to the complicated procedure with low success rate (56.9%). In one case it led to septicaemia followed by death. The total success rate was 84.5% in PTFC performed with an ultrathin needle (0.5 mm diameter); congested biliary ducts were successfully punctured in 87.9% and noncongested ducts in 72.2%. Severe complications consisted of one case of intraabdominal bleeding and one biliary extravasation. As shown in animal experiments, the superficial parenchymal lesion has not always the shape of a point. High accuracy also in noncongested biliary tracts and low mortality make PTFC superior to TVC and conventional percutaneous transhepatic cholangiography.     

Corrosion resistance of stainless chrome-nickel steels in sodium as a function of its oxygen content

The article describes an experimental apparatus for studying the corrosion resistance of construction materials in circulating liquid sodium, as well as methods for the continuous removal of oxides from the sodium by means of porous metal filters and for the determination of its oxygen content. It describes the results of corrosion experiments and measurements of mechanical properties performed on six brands of stainless steel, specimens of which were placed in sodium containing 3·10^–3% and (4–5)·10^–2% oxygen at a temperature of 550°. The flow rate was 1.5 m/sec. The results of the corrosion experiments indicate that the corrosion rate of Type 18CrSNi stainless steels in sodium containing as much as (4–5)·10^–2% oxygen does not exceed 21.3 mg/dm² per month; these steets are not subject to intergranular corrosion, and their mechanical properties remain virtually machanged.G. V. Akimov State Scientific Research Institute for the Preservation of Materials, Prague, Czechoslovak Soviet Socialist Republic Translated from Atomnaya Énergiya, Vol. 14, No. 4, pp. 375–382, April, 1963     

High-bandwidth Address Generation Unit

In this paper we present an efficient data fetch circuitry to retrieve several operands from a n-way parallel memory system in a single machine cycle. The proposed address generation unit operates with an improved version of the low-order parallel memory access approach. Our design supports data structures of arbitrary lengths and different odd strides. The experimental results show that our address generation unit is capable of generating eight 32 − bit addresses every 6 ns for different strides when implemented on a VIRTEX-II PRO xc2vp30-7ff1696 FPGA device using only trivial hardware resources.

Synchrotron-based characterization of arthroprosthetic CoCrMo particles in human bone marrow

Ti-Zr alloys have gained increasing attention as a new metallic biomaterial, being used as implants for both orthopedics and dentistry. More recently, our group found promising results for the Ti-45Zr alloy, which presented a low elastic modulus, a pronounced and excellent mechanic character, and excellent cell compatibility in vitro. However, its biocompatibility and potential to promote osteogenesis in vivo remained unclear. In the present study, the biocompatibility, osteointegration ability, and immune response effects of the Ti-45Zr alloy were evaluated in animal experiments. The results showed that the alloy had good blood compatibility and no body side effects. After implantation in vivo, the inflammation turned out well and was beneficial to the polarization of macrophages. Additionally, the Ti-45Zr alloy presented a good osteointegration ability. Overall, these results confirmed that the Ti-45Zr alloy can be used as a dental implant material.

     

Synthetic kenyaite as catalyst support for hydrocarbon combustion

Synthetic kenyaite is prepared in the system K₂O–SiO₂–H₂O. It is modified with cobalt and platinum in order to obtain catalysts for complete oxidation of n-hexane and benzene. The prepared samples are characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry (TG), differential thermal analysis (DTA), temperature programmed reduction (TPR) and Fourier transformed infrared (FTIR) spectroscopy. Co is loaded on kenyaite using ammonia method and classical impregnation. Bimetallic Co–Pt possess higher catalytic activity than monometallic cobalt for the oxidation of benzene, while, for hexane oxidation, the monometallic cobalt catalysts exhibit higher or close activity to that of Co–Pt samples. The catalysts prepared by ammonia method have better performance due to finer dispersion of the metal particles on the surface of the support.     

Diacetoxyiodobenzene and bis(trifluoroacetoxy)iodobenzene as photoinitiators for cationic polymerisations

Summary It is shown that i-butyl vinyl ether, tetrahydrofuran, epichlorhydrin and cyclohexene oxide, which undergo typically cationic polymerisation, are polymerised by UV-irradiation in the presence of diacetoxyiodobenzene or bis(trifluoroacetoxy)iodobenzene.     

4D Biofabrication: 3D Cell Patterning Using Shape‐Changing Films

A novel approach for fabrication of 3D cellular structures using new thermosensitive shape‐changing polymer films with photolithographically patterned surface—4D biofabrication is reported. The surface of shape‐changing polymer films is patterned to selectively adsorb cells in specific regions. The 2D cell pattern is converted to the 3D cell structure after temperature‐induced folding of the polymer films. This approach has a great potential in the field of tissue engineering and bioscaffolds fabrication.