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The paper is dedicated to the life prolongation of the tools designed for deep-hole drilling. Among available methods, an ion implantation process was used to improve the durability of tungsten carbide (WC)-Co guide pads. Nitrogen fluencies of 3 × 1017 cm−2, 4 × 1017 cm−2 and 5 × 1017 cm−2 were applied, and scanning electron microscope (SEM) observations, energy dispersive spectroscopy (EDS) analyses, X-ray photoelectron spectroscopy (XPS) and Secondary Ion Mass Spectrometry (SIMS) measurements were performed for both nonimplanted and implanted tools. The durability tests of nonimplanted and the modified tools were performed in industrial conditions. The durability of implanted guide pads was above 2.5 times greater than nonimplanted ones in the best case, presumably due to the presence of a carbon-rich layer and extremely hard tungsten nitrides. The achieved effect may be attributed to the dissociation of tungsten carbide phase and to the lubrication effect. The latter was due to the presence of pure carbon layer with a thickness of a few dozen nanometers. Notably, this layer was formed at a temperature of 200 °C, much smaller than in previously reported research, which makes the findings even more valuable from economic and environmental perspectives.

The hosts of Hantavirus are rodents, while they are transmitted to humans via aerosol, or by direct contact with them. The primary goal of the study was evaluation of the state of health of forestry workers by laboratory diagnosis of the diseases caused by Hantavirus Dobrava/Hantaan. The study covered a group of 820 randomly selected employees of the State Forests from 32 Forest Districts located in the area of the whole of Poland. The results of the study show that the largest number of positive results were registered in the Augustów Forest District -3 cases (10%), and in Piotrków Trybunalski -3 cases (11.5%). For the whole of Poland, 25 seropositive results were noted (3%) and 76 results were doubtful (9.3%). The results of the conducted study suggest the occurrence of Hantavirus Dobrava in large forest complexes on the territory of Poland. People residing and working in these areas are exposed to infection, and this exposure seems to be comparable with data from other countries.

IntroductionLyme borreliosis/Lyme disease is caused by Borrelia burgdorferi and is one of the most common vector-borne diseases transmitted by ticks.Material and MethodsA total of 136 Ixodes ricinus ticks, collected in the Ternopil (Ukraine) region, including 126 adults (70 females and 56 males), and 10 nymphs were examined. The identification of the species and their developmental form was based on morphological characteristics.ResultsPCR with B5S-Bor and 23S-Bor primers resulted in Borrelia burgdorferi sensu lato DNA amplification among six ticks (4.4%). The detailed analysis based on the DNA sequencing showed the presence of DNA of Borrelia afzelii in four samples; the remaining two represented Borrelia burgdorferi sensu lato complex, although their genospecies were not determined. The research confirmed the dominance of Borrelia afzelii genospecies in the ticks from Ukraine.ConclusionIt seems reasonable to undertake similar research in ticks from other regions of Ukraine. Knowledge in this field can be useful for public health and planning the prevention of tick-borne diseases.