Food of marine origin: Between benefits and potential risks. Part I. Canned fish on the Polish market

Chemical analyses were performed on 12 of the most popular varieties of canned fish on the Polish market. The contents of the nutritive substances of canned fish (protein, micro and macroelements, vitamins A₁, D₃, E, and fatty acids) and certain contaminants were determined. It was confirmed that canned fish is a good source of digestible proteins, fluoride, iodine, selenium, and vitamin D₃. The fundamental nutritive benefit of processed fish is the highly advantageous fatty acid composition, which imparts healthful effects. The high content of long-chained polyunsaturated fatty acids, which is not noted in other food products, is especially important.     

Dynamical cooling of semiconductor by contact layer

The subject of this paper is the presentation of a simple theoretical model of cooling of a semiconductor. The problem of the unsteady behaviour both of the semiconductor and of the cold plate that are in touch by the contact layer was studied analytically. The influence of the parameters of the materials and the cooling conditions was investigated. The results in the form of an analytical formula and graphs are presented and the heat stream is compared with the experimental results.     

The use of the Synthes 7.3-mm. cannulated screw in rearfoot and ankle surgery: a preliminary prospective study

The authors present a preliminary prospective study of the Synthes 7.3 mm. cannulated screw used in 31 rearfoot and ankle surgeries on 29 patients. The patients had a variety of rearfoot and ankle procedures performed, in which a total of 75 screws were placed across 47 arthrodesis or osteotomy sites. The percentage of union or healing was 95.74% for the joints or sites involved. The average healing time was 2.71 months. The techniques for placement of the screw are described.     

Overproduction of the Brucella melitensis heat shock protein DnaK in Escherichia coli and its localization by use of specific monoclonal antibodies in B. melitensis cells and fractions

The Brucella melitensis dnaK gene was amplified by the polymerase chain reaction using primers chosen according to the published sequence of B. ovis and cloned in multiple copy plasmids enabling expression under the control of the Plac promoter. Monoclonal antibodies (mAb) obtained by immunizing mice with B. melitensis B115 cell wall (CW) fraction or by infecting mice with virulent B. melitensis strain H38 and recognizing a 73-kDa band in immunoblotting of the B. melitensis CW fraction reacted with the cloned dnaK gene product and were thus shown to be specific for the heat shock protein DnaK. The anti-Dnak protein mAbs did not react with Escherichia coli control cells or cell lysates and could therefore be specific to Brucella DnaK protein epitopes. These mAbs were further used to study overproduction of the DnaK protein. B. melitensis DnaK overproduction in E. coli resulted in a defect in cell septation and formation of cell filaments. Immunogold labelling with the mAbs and electron microscopy localized the DnaK protein inside as well as outside the E. coli cells, probably resulting from lysis due to toxicity of the overproduced DnaK protein. These results indicated that overproduction of the B. melitensis DnaK protein in E. coli had similar physiological consequences as that of E. coli overproduced in E. coli. The DnaK protein localization in B. melitensis cells was essentially cytoplasmic, as shown by immunoelectron microscopy. Heat shock treatment of these cells resulted in increased binding of mAbs and labelling in the cytoplasm. However, in subcellular fractions the DnaK protein was predominantly found in the cell envelope fraction of B. melitensis, which could perhaps be due to interaction of the DnaK protein with membrane proteins.     

Bovine bone grafting in occipito-cervical fusion for atlanto-axial instability in rheumatoid arthritis

Bovine bone chips (Surgibone) were used in occipito-cervical fusion in nine patients with atlanto-axial instability due to rheumatoid arthritis. The patients were examined with CT 12-15 months after surgery. Graft resorbtion was observed in one patient. The other 8 patients showed preserved grafts, in most cases the grafts appeared to be in contact with the underlying bone. One patient was revised, and at the grafted site a bony bridge was found. In conclusion, the use of bovine chips in posterior occipito-cervical fusion will not lead to predictable bone union. However, there seem to be exceptions to that rule.     

Independent-Tree Ad hoc MulticAst Routing (ITAMAR)

Multicasting is an efficient means of one to many communication and is typically implemented by creating a multicasting tree. Because of the severe battery power and transmission bandwidth limitations in ad hoc networks, multicast routing can significantly improve the performance of this type of network. However, due to the frequent and hard-to-predict topological changes of ad hoc networks, maintenance of a multicasting tree to ensure its availability could be a difficult task. We borrow from the concept of Alternate Path routing, which has been studied for providing QOS routing, effective congestion control, security, and route failure protection, to propose a scheme in which a set of multicasting trees is continuously maintained. In our scheme, a tree is used until it fails, at which time it is replaced by an alternative tree in the set, so that the time between failure of a tree and resumption of multicast routing is minimal. In this paper, we introduce the basic scheme, termed ITAMAR, which is a framework for efficient multicasting in ad hoc networks. We present a number of heuristics that could be used in ITAMAR to compute a set of alternate trees. The heuristics are then compared in terms of transmission cost, improvement in the average time between multicast failures and the probability of usefulness. Simulations show significant gains over a wide range of network operational conditions. In particular, we show that using alternate trees has the potential of improving mean time between interruption by 100–600% in a 50 node network (for most multicast group sizes) with small increase in the tree cost and the route discovery overhead. We show that by renewing the backup tree set, probability of interruptions can be kept at a minimum at all times and that allowing some overlap among trees in the backup set increases the mean time between interruptions.     

Biomass productivity and phytoremediation potential of Salix alba and Salix viminalis

The aim of this work was to determine selected Salix clones’ capacities for biomass production and accumulation of heavy metal ions. Determination of the relationship between sorption of metals and biomass productivity was a further purpose of this study. Eight Salix viminalis cultivars and one Salix alba cultivar were analyzed. The taxa characterized by greatest biomass production were S. alba var. Chermesina and S. viminalis ‘1056’ (respectively 6.8 and 4.3 kg of fresh mass per shrub per year).The results have revealed significant differences among clones. The clones most effective in accumulating all five metals were S. viminalis ‘1154’ and ‘1054’. The studied Salix population was significantly diverse as regards accumulation efficiency. The differences between the highest and lowest heavy metal content in extreme clones were for: Cd 84%, Cu 90%, Hg 167%, Pb 190% and Zn 36%. At the same time, significant differences were observed in Salix structure. The greatest cellulose content was observed in S. viminalis ‘Sprint’ (49.69%) and the lowest in S. viminalis ‘1059’ (42.09%).     

Microstructural and optical characterization of TiO2 doped with ytterbium synthesized by sol-gel and Solar physical vapor deposition process

Pure and ytterbium doped TiO2 nanopowders in anatase phase have been prepared by sol-gel method (SGM) and Solar Physical Vapour Deposition process (SPVD). The physico-chemical parameters of the nanopowders have been described based on the results of micro-structural characterization performed by X-ray diffractometry, scanning electron microscopy, atomic force microscopy, and nitrogen sorption measurements. Thus, final micro-structural properties of SGM and SPVD titania nanopowders have been compared in detail revealing significant changes in the structure and morphology of these two types of materials. Addition of ytterbium had no significant effect on above-mentioned properties, although it modifies significantly the optical properties of the investigated materials. The luminescent properties of developed material were found to be comparable to bulk oxide materials and better than these reported earlier for ytterbium doped titania. In particular it has been shown that the luminescence of SPVD nanopowders is significantly stronger than this of SGM samples.     

Demand re‐registration for PCS database restoration

In a Personal Communications Services (PCS) network, mobility databases such as Home Location Register (HLR) and Visitor Location Register (VLR) are utilized to support mobility management for Mobile Stations (MSs). If the location databases fail, the location information loss or corruption will seriously degrade the service offered to the subscribers. In this paper, we propose a new VLR failure recovery scheme called demand reregistration. In this scheme, the VLR broadcasts a reregistration request to all MSs after the VLR failure. When an MS receives the reregistration request, it sends a registration message to the VLR to recover the location record. Since all MSs will reregister after receiving the broadcasting request, traffic jam (and thus collisions) may occur. If a collision occurs, then the involved MSs must resend the registration messages. This paper studies the performance of demand reregistration by investigating how effectively the reregistration can recover the location record for an MS before the first MS call termination occurs. Our results indicate that demand reregistration can effectively recover VLR failure.