| 1. |
- Füchtbauer, Anders Foller, 1984, et al.
(author)
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Lighting Up DNA with the Environment-Sensitive Bright Adenine Analogue qAN4
- 2020
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In: Chempluschem. - : Wiley. - 2192-6506. ; 85:2, s. 319-326
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Journal article (peer-reviewed)abstract
- The fluorescent adenine analogue qAN4 was recently shown to possess promising photophysical properties, including a high brightness as a monomer. Here we report the synthesis of the phosphoramidite of qAN4 and its successful incorporation into DNA oligonucleotides using standard solid-phase synthesis. Circular dichroism and thermal melting studies indicate that the qAN4-modification has a stabilizing effect on the B-form of DNA. Moreover, qAN4 base-pairs selectively with thymine with mismatch penalties similar to those of mismatches of adenine. The low energy absorption band of qAN4 inside DNA has its peak around 358 nm and the emission in duplex DNA is partly quenched and blue-shifted (ca. 410 nm), compared to the monomeric form. The spectral properties of the fluorophore also show sensitivity to pH; a property that may find biological applications. Quantum yields in single-stranded DNA range from 1-29 % and in duplex DNA from 1-7 %. In combination with the absorptive properties, this gives an average brightness inside duplex DNA of 275 M-1 cm(-1), more than five times higher than the most used environment-sensitive fluorescent base analogue, 2-aminopurine. Finally, we show that qAN4 can be used to advantage as a donor for interbase FRET applications in combination with adenine analogue qA(nitro) as an acceptor.
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| 2. |
- Hoffman, Tove, et al.
(author)
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Association between guilds of birds in the African-Western Palaearctic region and the tick species Hyalomma rufipes, one of the main vectors of Crimean-Congo hemorrhagic fever virus.
- 2022
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In: Microorganisms. - : MDPI AG. - 2076-2607. ; 10
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Journal article (peer-reviewed)abstract
- The migratory behavior of wild birds contributes to the geographical spread of ticks and their microorganisms. In this study, we aimed to investigate the dispersal and co-occurrence of Francisella and spotted fever group Rickettsia (SFGR) in ticks infesting birds migrating northward in the African-Western Palaearctic region (AWPR). Birds were trapped with mist nests across the Mediterranean basin during the 2014 and 2015 spring migration. In total, 575 ticks were collected from 244 birds. We screened the ticks for the species Francisella tularensis, the genus Francisella, and SFGR by microfluidic real-time PCR. Confirmatory analyses and metagenomic sequencing were performed on tick samples that putatively tested positive for F. tularensis during initial screenings. Hyalomma rufipes was the most common tick species and had a high prevalence of Francisella, including co-occurrence of Francisella and SFGR. Metagenomic analysis of total DNA extracted from two H. rufipes confirmed the presence of Francisella, Rickettsia, and Midichloria. Average nucleotide identity and phylogenetic inference indicated the highest identity of the metagenome-assembled genomes to a Francisella-like endosymbiont (FLE), Rickettsia aeschlimannii, and Midichloria mitochondrii. The results of this study suggest that (i) FLE- and SFGR-containing ticks are dispersed by northbound migratory birds in the AWPR, (ii) H. rufipes likely is not involved in transmission of F. tularensis in the AWPR, and (iii) a dual endosymbiosis of FLEs and Midichloria may support some of the nutritional requirements of H. rufipes.
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| 3. |
- Hoffman, Tove, et al.
(author)
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Co-Occurrence of Francisella, Spotted Fever Group Rickettsia, and Midichloria in Avian-Associated Hyalomma rufipes
- 2022
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In: Microorganisms. - : MDPI. - 2076-2607. ; 10:7
-
Journal article (peer-reviewed)abstract
- The migratory behavior of wild birds contributes to the geographical spread of ticks and their microorganisms. In this study, we aimed to investigate the dispersal and co-occurrence of Francisella and spotted fever group Rickettsia (SFGR) in ticks infesting birds migrating northward in the African-Western Palaearctic region (AWPR). Birds were trapped with mist nests across the Mediterranean basin during the 2014 and 2015 spring migration. In total, 575 ticks were collected from 244 birds. We screened the ticks for the species Francisella tularensis, the genus Francisella, and SFGR by microfluidic real-time PCR. Confirmatory analyses and metagenomic sequencing were performed on tick samples that putatively tested positive for F. tularensis during initial screenings. Hyalomma rufipes was the most common tick species and had a high prevalence of Francisella, including co-occurrence of Francisella and SFGR. Metagenomic analysis of total DNA extracted from two H. rufipes confirmed the presence of Francisella, Rickettsia, and Midichloria. Average nucleotide identity and phylogenetic inference indicated the highest identity of the metagenome-assembled genomes to a Francisella-like endosymbiont (FLE), Rickettsia aeschlimannii, and Midichloria mitochondrii. The results of this study suggest that (i) FLE- and SFGR-containing ticks are dispersed by northbound migratory birds in the AWPR, (ii) H. rufipes likely is not involved in transmission of F. tularensis in the AWPR, and (iii) a dual endosymbiosis of FLEs and Midichloria may support some of the nutritional requirements of H. rufipes.
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| 4. |
- Millanzi, Egino, 1968-
(author)
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Housing finance methods in urban Tanzania : The case of households in Kinondoni Municipality, Dar es Salaam, Tanzania
- 2023
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Doctoral thesis (other academic/artistic)abstract
- Effective housing finance methods require the interrelationships between the housing finance system components such as banking and capital markets, land registry, the housing sector, and macroeconomic and socioeconomic aspects. Nonetheless, despite the exclusion of the majority of the households by formal long-term housing finance methods, Tanzania has experienced substantial improvement in housing development in the last two decades. This study explored how the aspects of housing finance methods, household financing decisions, housing affordability and expenditures are linked to effective housing finance in Tanzania. The study integrated a range of theories, namely; financial theories, housing finance system theory as well as bricolage and effectuation approach to explain the household's financing decisions. The explanatory sequential mixed methods design was used to determine household financing options. Results indicate that informal finance and microfinance are preferred relative to housing mortgage finance methods. The market share of housing mortgages is less than 10 per cent. Moreover, the study established that informal and formal methods coexist. Findings also confirmed that community-based finance schemes play an important role in the housing finance system, and that many house owners use more than one source of finance. This implies that the bricolage and effectuation approach to housing results in emerging unconventional housing finance methods. The study further found that housing expenditures are constrained by large family size, low household income, lack of property collateral, high-interest rates and lack of affordability, all of which linked to poor employment status, house type, and lack of property collateral and high-interest rates. The study also revealed that different choices of the housing finance methods are influenced by age of breadwinners, level of employment and interest rates. This implies that, the macroeconomic environment, banking industry and capital markets constrain the household's financing decisions, housing expenditures and affordability. Therefore, a multisector policy approach is required that can help to provide for effective housing finance methods, enhance housing affordability and tackle housing expenditures. The policies need to ensure effective housing delivery system, stability of the interest rates, inclusive and affordable financial services, effective land registration systems, strong banking industry and capital markets and better follow up of housing expenditures.
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| 5. |
- Wilhelmsson, Peter, et al.
(author)
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Clinical/serological outcome in humans bitten by Babesia species positive Ixodes ricinus ticks in Sweden and on the Aland Islands
- 2020
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In: Ticks and Tick-borne Diseases. - : ELSEVIER GMBH. - 1877-959X .- 1877-9603. ; 11:4
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Journal article (peer-reviewed)abstract
- The risk of contracting babesiosis after a tick bite in Sweden and on the Aland Islands, Finland, is unknown. We investigated clinical and serological outcomes in people bitten by Ixodes ricinus ticks positive for Babesia species. Ticks, blood and questionnaires were obtained from study participants in Sweden and on the Aland Islands. Sixty-five of 2098 (3.1 %) ticks were positive by real-time PCR. Three Babesia species were detected, Babesia microti (n = 33), B. venatorum (n = 27) and B. capreoli (n = 5), the latter species not known to cause human infection. Half (46 %) of the Babesia PCR-positive ticks also contained Borrelia spp. Fifty-three participants bitten by a Babesia PCR-positive tick and a control group bitten by a Babesia PCR-negative tick were tested for B. microti IgG antibodies by IFA. The overall seroprevalence was 4.4 %, but there was no significant difference between the groups. None of the participants seroconverted and no participant with a Babesia PCR-positive tick sought medical care or reported symptoms suggestive of babesiosis. Given the prevalence of Babesia in I. ricinus ticks in southern Sweden and on the Aland Islands, babesiosis should be considered a possible diagnosis in symptomatic residents who seek medical care following tick exposure.
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| 6. |
- Wilhelmsson, Sofia, et al.
(author)
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Effects of a training intervention for Swedish pig transport drivers on physical workload and time efficiency during loading
- 2022
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In: International Journal of Industrial Ergonomics. - : Elsevier BV. - 0169-8141 .- 1872-8219. ; 92
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Journal article (peer-reviewed)abstract
- Slaughter transportation of pigs can be considered a high-risk occupation, but has received very little scientific attention. We investigated the effect of a training intervention on transport drivers’ physical workload, in terms of postures and movements, and time efficiency during loading of finishing pigs for slaughter transport. The training targeted pig handling and ergonomic working principles and was expected to decrease physical workload and loading time per pig, due to less aversive handling and less stress-related pig behaviour. Inclinometric recordings of elevation and velocity of upper arms were used to assess workload before and after training. Seventeen drivers were studied during loading of 4,721 pigs at 36 loadings on 31 Swedish farms under varying conditions. Eleven of the drivers were trained and 10 of these were observed also after training. Overall mean peak loads for right arm elevation, right arm velocity and loading time per pig were 56.4°, 184°/s and 16.2 s, respectively. We were unable to confirm our hypotheses regarding effects of training on physical workload and loading time.
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| 7. |
- Wilhelmsson, Sofia, et al.
(author)
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Physical workload and psychosocial working conditions in Swedish pig transport drivers
- 2021
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In: International Journal of Industrial Ergonomics. - : Elsevier BV. - 0169-8141 .- 1872-8219. ; 83
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Journal article (peer-reviewed)abstract
- Working conditions of 20 Swedish pig transport drivers (PTD) were assessed by a questionnaire, a workshop, and recorded postures and movements during on-farm loading, driving, unloading at abattoir and vehicle cleaning. High arm positions and high frequencies of shoulder problems indicated an excessive physical load on shoulders. Extreme crouching postures inside vehicles and high frequencies of lower back problems indicated high load on the back of PTDs. Inadequate design of on-farm loading areas was associated with knee discomfort. Observed variation in workload between PTDs could be explained by differences in physical working environment and pig handling practices. PTDs reported high job satisfaction and commitment although conflicts with farmers and official veterinarians, as well as regulatory conflicts were emphasized. We conclude that issues of inadequate farm and abattoir facilities, stakeholder conflicts and insufficient training in animal handling need to be addressed to ensure sustainable PTD working conditions.
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| 8. |
- Wypijewska Del Nogal, Anna Wiktoria, 1982, et al.
(author)
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Getting DNA and RNA out of the dark with 2CNqA: a bright adenine analogue and interbase FRET donor
- 2020
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In: Nucleic Acids Research. - : Oxford University Press (OUP). - 0305-1048 .- 1362-4962. ; 48:14, s. 7640-7652
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Journal article (peer-reviewed)abstract
- With the central role of nucleic acids there is a need for development of fluorophores that facilitate the visualization of processes involving nucleic acids without perturbing their natural properties and behaviour. Here, we incorporate a new analogue of adenine, 2CNqA, into both DNA and RNA, and evaluate its nucleobase-mimicking and internal fluorophore capacities. We find that 2CNqA displays excellent photophysical properties in both nucleic acids, is highly specific for thymine/uracil, and maintains and slightly stabilises the canonical conformations of DNA and RNA duplexes. Moreover, the 2CNqA fluorophore has a quantum yield in single-stranded and duplex DNA ranging from 10% to 44% and 22% to 32%, respectively, and a slightly lower one (average 12%) inside duplex RNA. In combination with a comparatively strong molar absorptivity for this class of compounds, the resulting brightness of 2CNqA inside double-stranded DNA is the highest reported for a fluorescent base analogue. The high, relatively sequence-independent quantum yield in duplexes makes 2CNqA promising as a nucleic acid label and as an interbase Forster resonance energy transfer (FRET) donor. Finally, we report its excellent spectral overlap with the interbase FRET acceptors qA(nitro) and tC(nitro), and demonstrate that these FRET pairs enable conformation studies of DNA and RNA.
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