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At immediate surroundings of a fiberglass plant in Central Sweden, vegetation shows toxicity symptoms. Soils and birch ( Roth) leaves were sampled. The soil was analysed for water soluble and organic bound boron, carbon, nitrogen, and pH. Vegetation was analysed for total boron. Both fractions of boron in the soils increased towards the factory. Organic bound boron increased irregularly because of its strong correlation to carbon content which varied in the area. The C/N ratio increased nearer the industry due to the harmful effect of boron on the decomposition of organic matter. No relation between pH and the distance from the emission source was visible, but B/C ratio was found to increase with increasing pH of the soil. Boron levels in birch leaves were elevated very much close to the factory. The geographical distribution of high levels of boron in birch, corresponded well with high values in soils, and also with the main wind directions. The limit values for visible injury on birch were found to be around 5 ppm of water-soluble boron in soil and around 200 ppm in leaves.Betula pendula

Background: Calf diarrhea is a major cause of morbidity and mortality in the livestock sector worldwide and it can be caused by multiple infectious agents. In Ethiopia, cattle are the most economically important species within the livestock sector, but at the same time the young animals suffer from high rates of morbidity and mortality due to calf diarrhea. However, studies including both screening and molecular characterization of bovine enteric pathogens are lacking. Therefore, we aimed to both detect and molecularly characterize four of the major enteric pathogens in calf diarrhea, Enterotoxigenic Escherichia coli (E. coli K99 +), Cryptosporidium spp., rotavirus A (RVA), and bovine coronavirus (BCoV) in calves from central Ethiopia. Diarrheic and non-diarrheic calves were included in the study and fecal samples were analyzed with antigen-ELISA and quantitative real-time PCR (qPCR). Positive samples were further characterized by genotyping PCRs., Results: All four pathogens were detected in both diarrheic and non-diarrheic calves using qPCR and further characterization showed the presence of three Cryptosporidium species, C. andersoni, C. bovis and C. ryanae. Furthermore, genotyping of RVA-positive samples found a common bovine genotype G10P[11], as well as a more unusual G-type, G24. To our knowledge this is the first detection of the G24 RVA genotype in Ethiopia as well as in Africa. Lastly, investigation of the spike gene revealed two distinct BCoV strains, one classical BCoV strain and one bovine-like CoV strain., Conclusions: Our results show that Cryptosporidium spp., E. coli K99 + , RVA and BCoV circulate in calves from central Ethiopia. Furthermore, our findings of the rare RVA G-type G24 and a bovine-like CoV demonstrates the importance of genetic characterization., (© 2024. The Author(s).)

Exchange of viral segments between one or more influenza virus subtypes can contribute to a shift in virulence and adaptation to new hosts. Among several influenza subtypes, H9N2 is widely circulating in poultry populations worldwide and has the ability to infect humans. Here, we studied the reassortant compatibility between chicken H9N2 with N1-N9 gene segments of wild bird origin, either with an intact or truncated stalk. Naturally occurring amino acid deletions in the NA stalk of the influenza virus can lead to increased virulence in both mallard ducks and chickens. Our findings show extended genetic compatibility between chicken H9Nx gene segments and the wild-bird NA with and without 20 amino acid stalk deletion. Replication kinetics in avian, mammalian and human cell lines revealed that parental chH9N2 and rH9N6 viruses with intact NA-stalk replicated significantly better in avian DF1 cells compared to human A549 cells. After introducing a stalk deletion, an enhanced preference for replication in mammalian and human cell lines could be observed for rH9N2 Δ (H6), rH9N6 Δ and rH9N9 Δ compared to the parental chH9N2 virus. This highlights the potential emergence of novel viruses with variable phenotypic traits, warranting the continuous monitoring of H9N2 and co-circulating subtypes in avian hosts., (© 2023. The Author(s).)

Background: Since the beginning of the COVID-19 pandemic, new variants of significance to public health have emerged. Consequently, early detection of new mutations and variants through whole-genome sequencing remains crucial to assist health officials in employing appropriate public health measures., Methods: We utilized the ARTIC Network SARS-CoV-2 tiled amplicon approach and Nanopore sequencing to sequence 4,674 COVID-19 positive patient samples from Uppsala County, Sweden, between week 15 and 52 in 2021. Using this data, we mapped the circulating variants of concern (VOC) in the county over time and analysed the Spike (S) protein mutational dynamics in the Delta variant throughout 2021., Results: The distribution of the SARS-CoV-2 VOC matched the national VOC distribution in Sweden, in 2021. In the S protein of the Delta variant, we detected mutations attributable to variants under monitoring and variants of interest (e.g., E484Q, Q613H, Q677H, A222V and Y145H) and future VOC (e.g., T95I and Y144 deletion, which are signature mutations in the Omicron variant). We also frequently detected some less well-described S protein mutations in our Delta sequences, that might play a role in shaping future emerging variants. These include A262S, Q675K, I850L, Q1201H, V1228L and M1237I. Lastly, we observed that some of the Delta variant's signature mutations were underrepresented in our study due to artifacts of the used bioinformatics tools, approach and sequencing method. We therefore discuss some pitfalls and considerations when sequencing SARS-CoV-2 genomes., Conclusion: Our results suggest that genomic surveillance in a small, representative cohort can be used to make predictions about the circulating variants nationally. Moreover, we show that detection of transient mutations in currently circulating variants can give valuable clues to signature mutations of future VOC. Here we suggest six such mutations, that we detected frequently in the Delta variant during 2021. Lastly, we report multiple systematic errors that occurred when following the ARTIC Network SARS-CoV-2 tiled amplicon approach using the V3 primers and Nanopore sequencing, which led to the masking of some of the important signature mutations in the Delta sequences., (© 2022. The Author(s).)

We describe a flight-associated infection scenario of seven individuals with a B.1.617.2 (Delta) lineage, harbouring an S:E484Q point mutation. In Sweden, at least 10% of all positive SARS-CoV-2 samples were sequenced in each county; the B.1.717.2 + S:E484Q combination was not detected in Sweden before and was imported within the scenario described in this report. The high transmission rate of the delta lineage combined with the S:E484Q mutation, associated with immune escape in other lineages, makes this specific genetic combination a possible threat to the global fight against the COVID-19 pandemic. Even within the Omicron wave, the B.1.617.2 + S:E484Q variant appeared in community samples in Sweden, as it seems that this combination has an evolutionary gain compared to other B.1.617.2 lineages. The here described genomic combination was not detectable with the common fasta file-based Pango-lineage analysis, hence increasing the probability of the true global prevalence to be higher.

We wished to establish a reproducible model for fracture fixation to be used in fracture healing research and therefore developed an external fixation construct and surgical procedure adapted to Sprague-Dawley rats. We evaluated the mechanical properties of the construct in brass rods and rat bone, in an Instron test machine with axial and transverse loading, and the in vivo performance. We found that the mechanical properties of the construct in brass rods were predictable and could be repeated in rat femora. In all tests, the axial load was about 10 times the transverse for the same degree of deformation. The stiffness among fixators was uniform. 1 mm pins caused about 50% less stiffness than 1.2 mm pins in axial loading of rat bone (p < 0.001) and brass rods (p < 0.001) as well as in transverse loading of brass rods (p < 0.001). Loosening of 1 or 2 screws that lock the pins to the fixator reduced stiffness by about 50% in axial loading of rat bone (p = 0.009) and brass rods (p = 0.05). A change in the distance between the bone surface and the fixator was linearly related to the stiffness in axial loading of rat bone (p < 0.001) and brass rods (p < 0.001) and in transverse loading of brass rods (p < 0.001). If the bone ends touched each other, the axial stiffness of the construct increased almost 10 times (265 N/mm), as compared to a fracture gap size of 2 mm (31 N/mm). In vivo experiments had a complication rate of less than 10% when we used 1.2 mm pins, 6 mm offset and rats weighing 350-450 g. Our method and device for experimental external fixation of rat femora are reliable and the findings are reproducible. These can be used in bone repair and fracture healing research.

Copper production in Falun, central Sweden, has emitted sulfur dioxide (SO2) and metals to the air during at least 1000 years. Emissions peaked in the 17th century when Falun produced 2/3 of the world's copper supply. This area offers unique opportunities to study long-term effects of acid deposition and metal pollution, including recovery following the three centuries of decreasing SO2 and metal deposition. Here we present a 1000-yr perspective on local emissions of SO2, estimated air concentrations and dry deposition of SO2, as well as results on acidification and metal pollution of soils and lakes. Despite a long period when deposition of SO2 exceeded the critical load, soil acidification is limited to the most heavily polluted area 12 km NW and SE from the mine. According to diatom analyses of take sediments, only 8 of 14 lakes have become acidified (0.4-0.8 pH units). None of these lakes show recovery from acidification, probably due to large amounts of sulfate still accumulated in the soils and changes in land use.

Field trials concerning the establishment of plant cover on a deposit of wastes from the Ammeberg zinc mine in central Sweden were carried out during 1976-1985. Different soil conditioners and manures were applied and plant species cultivars were evaluated with regard to plant biomass, vigour, durability and content of zinc, lead and cadmium. Sewage sludge and topsoil led to better establishment of grasses than did municipal waste, straw and hydraulic seeding. After 2 years, Festuca rubra and Poa pratensis dominated the swards. Other species (Dactylis glomerata, Bromus inermis, Lolium perenne, Phleum nodosum, Festuca pratensis and F. arundinacea) constituted only a minor part of the stand. After 10 years, F. rubra was the most dominant species, while native Agrostis tenuis had invaded 20-50% of the area within the plots. Merlin was the clearly dominant red fescue cultivar. The concentration of zinc in shoots (616 mg kg(-1) dw) was about 10% of that in the soil. Zinc concentration decreased with increasing biomass above ground. It increased with age in Scots pine needles and was very high in birch leaves. Grasses survived longer than legumes in the zinc sand waste. Among the surviving grasses was a group with high (3800 mg kg(-1) dw) and a group with low (320 mg kg(-1) dw) zinc concentrations. The low group included Merlin red fescue and Sobel creeping bent. The cultivar Merlin contained a much lower zinc concentration than the other cultivars of red fescue (375 and 624 mg kg(-1) dw, respectively). A large amount of root biomass was present in plots with dominating Merlin red fescue (1715 g m(-2)), 97% of which was concentrated in the top 10 cm of the soil. The concentration of zinc in the roots was very high (13 000-25 000 mg kg(-1) dw). Nitrate fertilizer, especially ammonium nitrate, and acidic water (pH 4.3) increased zinc leaching.