1.To counteract the decline of farmland biodiversity in Europe, it is crucial to recognize habitats that are hot spots. Old rural settlements (e.g. villages) may be such important habitats, although these presumably biodiversity-rich habitats have received little attention. Socioeconomic changes in central-eastern Europe since 1989 mean that old homesteads and farmsteads are being replaced by new ones. 2. We investigated bird species composition, richness and abundance at three spatial scales (single rural property, village and landscape) in the farmland of Poland to test: (i) their association with age (built before vs. after 1989) and type of property (farmstead vs. homestead), (ii) their relationship with the increasing share of new homesteads at the village scale and (iii) the difference in diversity between the village environment and four other environments (open fields, forest-field ecotones, forests and towns) at the landscape scale. 3. At the single property scale, 15 out of 33 species preferred old farmsteads, while only one species preferred new homesteads. Old properties hosted a higher number of species and individuals than new ones, and farmsteads hosted a higher number of species than homesteads. 4. At the village scale, bird species richness and abundance were markedly negatively associated with the proportion of new homesteads. At the landscape scale, species composition differed between villages and the other environments, and villages had the highest average bird abundance. 5. Synthesis and applications. Rural villages and old farmsteads are important habitats for many farmland birds; thus, the increasing number of new homesteads not associated with farmland production will likely lead to a substantial further decline of farmland bird numbers and biodiversity. To counteract this process, we recommend (i) implementing educational programmes to develop rural residents' awareness about the importance of farmsteads and homesteads for biodiversity, (ii) including villages and farmsteads and consideration of birdfriendly habitats within these as part of EU conservation policies and (iii) compensating for changes in the structure of rural villages by increasing the amount of similar alternative habitats in the surrounding landscape.

Multifunctional core/shell type nanomaterials composed of nanocrystalline, lanthanide doped fluorides and gold nanoparticles (Au NPs) were successfully prepared. The products were synthesized to combine luminescence properties of the core NPs, i.e., LnF 3 /SiO 2 −NH 2 and KLn 3 F 10 / SiO 2 −NH 2 , and plasmonic activity of the shell Au NPs within a single nanomaterial. The luminescent lanthanide NPs (10 or 150−200 nm) were separated from the gold NPs (6−30 nm) using an amine modified silica shell (thickness ≈30 nm). The synthesized products exhibited bright green (Tb 3+ ) and red (Eu 3+ ) emission under UV light irradiation. Surface modification with Au NPs influenced the product emission and luminescence decay characteristics. The luminescent-plasmonic nanomaterials were used as platforms for surface enhanced Raman scattering (SERS) measurements. 4-Mercaptobenzoic acid, choline, and T4 bacteriophages were utilized as SERS probes. For all synthesized nanomaterials, the SERS spectra for all probes studied exhibited higher intensity in comparison with the spectra measured using a commercial SERS substrate. Cytotoxicity of the products was evaluated in fibroblast cells. The results obtained showed biocompatibility of the synthesized nanomaterials in a dose-dependent manner.

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A facile coprecipitation reaction between Ce(3+), Gd(3+), Tb(3+), and F(-) ions, in the presence of glycerine as a capping agent, led to the formation of ultrafine, nanocrystalline CeF3:Tb(3+) 5%, Gd(3+) 5% (LnF3). The as-prepared fluoride nanoparticles were successfully coated with an amine modified silica shell. Subsequently, the obtained LnF3@SiO2@NH2 nanostructures were conjugated with 4-ethoxybenzoic acid in order to prove the possibility of organic modification and obtain a new functional nanomaterial. All of the nanophosphors synthesized exhibited intense green luminescence under UV light irradiation. Based on TEM (transmission electron microscopy) measurements, the diameters of the cores (≈12 nm) and core/shell particles (≈50 nm) were determined. To evaluate the cytotoxic activity of the nanomaterials obtained, their effect on human erythrocytes was investigated. LnF3 nanoparticles were bound to the erythrocyte membrane, without inducing any cytotoxic effects. After coating with silica, the nanoparticles revealed significant cytotoxicity. However, further functionalization of the nanomaterial with -NH2 groups as well as conjugation with 4-ethoxybenzoic acid entailed a decrease in cytotoxicity of the core/shell nanoparticles.

For a number of years nanomaterials have been continuously devised and comprehensively investigated because of the growing demand for them and their multifarious applications, especially in medicine. This paper reports on the properties of SrF 2 nanoparticles (NPs) for applications in biomedicine, showing effective ways of their synthesis and luminescence under near infrared radiation - upconversion. NPs doped with lanthanide, Ln 3+ ions (where Ln = Yb, Ho, Er, Tm) were prepared by the hydrothermal method and subjected to comprehensive studies, from determination of their structure and morphology, revealing small, 15 nm structures, through spectroscopic properties, to cytotoxicity in vitro . The effects of such factors as the reaction time, type and amount of precipitating compounds and complexing agents on the properties of products were characterized. The cytotoxicity of the synthesized and functionalized NPs was investigated, using human fibroblast cell line (MSU-1.1). The synthesized structures may decrease cells’ proliferation in a dose-dependent manner in the measured concentration range (up to 100 µg/mL). However, the cells remain alive according to the fluorescent assay. Moreover, the treated cells were imaged using confocal laser scanning microscopy. Cellular uptake was confirmed by the presence of upconversion luminescence in the cells.

Increase in the level of reactive oxygen species (ROS) is a common response to stress factors, including exposure to metals. ROS over-production is associated with oxidation of lipids, proteins, and nucleic acids. It is suggested that the products of oxidation are not solely the markers of oxidative stress but also signaling elements. For instance, it has been shown in animal models that mRNA oxidation is a selective process engaged in post-transcriptional regulation of genes expression and that it is associated with the development of symptoms of several neurodegenerative disorders. In the present study, we examined the impact of short-term cadmium (Cd) stress on the level of two RNA oxidation markers: 8-hydroxyguanosine (8-OHG) and apurinic/apyrimidinic sites (AP-sites, abasic sites). In the case of 8-OHG, a significant increase was observed after 3 h of exposure to moderate Cd concentration (10 mg/l). In turn, high level of AP-sites, accompanied by strong ROS accumulation and lipid peroxidation, was noted only after 24 h of treatment with higher Cd concentration (25 mg/l). This is the first report showing induction of RNA oxidations in plants response to stress factors. The possible signaling and gene regulatory role of oxidatively modified transcripts is discussed.

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