3,347 research outputs found
Reviewing the Author-Function in the Age of Wikipedia
No full textIn Reviewing the Author-Function in the Age of Wikipedia, Amit Ray and Erhardt Graeff examine how wiki technology challenges traditional concepts of authorship and authority in knowledge production. The authors build on poststructuralist theory, particularly Roland Barthes\u27s Death of the Author and Michel Foucault\u27s concept of the author-function, to analyze how wikis destabilize individual authorship in favor of collaborative, community-driven content creation.
The essay argues that wikis represent a fundamental shift from the Romantic notion of the solitary author-genius to what they term the wiki writing process —a dynamic system where traditional roles of reader, writer, and editor blur into a unified community of users. Using Wikipedia as a primary case study, the authors demonstrate how the platform\u27s structure (article, discussion, and history pages) creates a digital palimpsest that archives all contributions while enabling continuous revision.
Through analysis of Wikipedia\u27s editing patterns and community oversight mechanisms, Ray and Graeff show how wikis embody poststructuralist principles in practice, creating what they call serial collaborations that exist in perpetual flux. The authors conclude that wikis represent an evolved form of textual production that realizes Foucault\u27s vision of discourse freed from traditional authorial constraints, offering new possibilities for collaborative knowledge creation while challenging established notions of intellectual authority and ownership
Using ecological and field survey data to establish a national list of the wild bee pollinators of crops
No full textMM was funded by grant INIA-RTA2013-00139-C03-01 (MINECO and FEDER)Hutchinson, L.A., Oliver, T.H., Breeze, T.D., Bailes, E.J., Brünjes, L., Campbell, A.J., Erhardt, A., de Groot, G.A., Földesi, R., García, D., Goulson, D., Hainaut, H., Hambäck, P.A., Holzschuh, A., Jauker, F., Klatt, B.K., Klein, A.-M., Kleijn, D., Kovács-Hostyánszki, A., Krimmer, E., McKerchar, M., Miñarro, M., Phillips, B.B., Potts, S.G., Pufal, G., Radzevičiūtė, R., Roberts, S.P.M., Samnegård, U., Schulze, J., Shaw, R.F., Tscharntke, T., Vereecken, N.J., Westbury, D.B., Westphal, C., Wietzke, A., Woodcock, B.A., Garratt, M.P.D
The β-casein in camels: molecular characterization of the CSN2 gene, promoter analysis and genetic variability.
No full textThe β-casein is the most abundant protein in camel milk and its encoding gene (CSN2) is considered in other species a 'major' gene for the presence of alleles associated to different level of expression. In the present paper, we report for the first time the characterization of the nucleotide sequence of the whole β-casein-encoding gene (CSN2) plus 2,141 bp at the 5'-flanking region in Camelus dromedarius. The promoter region and the complete cDNA are also provided for the first time in Camelus bactrianus. The gene is spread over 7.8 kb and consists of 9 exons varying in length from 24 bp (exon 5) to 519 bp (exon 7), and 8 introns from 95 bp (intron 5) to 1,950 bp (intron 1). The composite response element (CoRE) region was identified in the promoter, whereas the presence of mature microRNA sequences improves the knowledge on the factors putatively involved in the gene regulation. A total of 46 polymorphic sites have been detected. The transition g.2126A>G falls within the TATA-box of dromedary CSN2 promoter with a putative influence on the transcription factor binding activity. The frequency of the G allele is 0.35 in a population of 180 she-camels belonging to 4 different ecotypes. In the same population, a conservative SNP (g.4175C>A) was found at the codon 7 of the signal peptide, whereas a comparative analysis with a cDNA sequence available in the database evidenced a missense SNP (g.4180T(Leu)>G(Arg)) at exon 2. Four SNPs were found in the bactrian camel. The SNP c.666G>A is responsible for the amino acid change Met(201)→Ile and it represents the first missense allele at the β-casein in camels. Finally, five interspersed repeated elements were identified at intronic level, whereas the presence of putative bio-functional peptides belonging to ACE-inhibitor and anti-oxidative families confirms the potential protective role of the camel milk for the human nutrition
Messersmith, G.S., Berlin. To John G. Erhardt, Bordeaux.
No full textThanks Erhardt for his note; believes career might have been ruined except for support of friends; comments on Nicholas Murray Butler's statement that his "heart wept for his country at the spectacle of what happened at the Consulate General at Berlin"; the Einsteins conducted their application for a visa with the press before applying at the Consulate; thinks they were afraid to appear in person because of Einstein's known connection with radical organizations
The invasive plant Impatiens glandulifera affects mycorrhizal fungi, plant and invertebrate diversity in deciduous forests
No full textNon-native plant species have the potential to affect an ecosystem by changing species diversity, community structure and interactions among organisms. It is therefore important to understand potential mechanisms that contribute to the success of invasive plants. In the context of my PhD thesis, I examined the effect of the invasive annual herb I. glandulifera on mycorrhizal, plant and invertebrate diversity in a deciduous forest near Basel (Switzerland). I also studied the potential mechanism that could contribute to the success of I. glandulifera. A controlled field experiment was set up in three forest areas that were affected to a different extend (little, moderatly, high) by a former wind storm. In each area, three different plot types were installed: plots invaded by I. glandulifera, plots from which the invasive plants had been manually removed and plots which were no yet colonized by the invasive plant. The results of my thesis demonstrate that I. glandulifera affects above and as well as belowground organisms and has the potential to change soil conditions.
Aboveground gastropod richness and abundance were found to be higher in invaded plots than in control plots. The presence of I. glandulifera also altered the composition of gastropod species. Belowground fewer types of ectomycorrhiza were found on root systems of F. sylvatica saplings. Moreover, in plots with I. glandulifera the composition of ectomycorrhiza morphotypes was shifted. Considering mycorrhizal colonisation on fine roots saplings of both tree species, the presence of the invasive plant resulted in a reduction of ectomycorrhizal colonisation of F. sylvatica saplings and of arbuscular mycorrhiza colonisation on A. pseudoplatanus. Thus, disruption of mycorrhizal symbiosis probably led to a lower biomass and survival rate in saplings of both species grown in invaded plots. Additional results showed that soil moisture, soil pH, available phosphorus and microbial activity were increased in invaded plots.
Increased gastropods abundance and richness could be explained by higher soil moistures and damped soil temperature in invaded plots. However, measured changes in soil conditions did not affect mycorrhizal colonisation and performance of both sapling species. Therefore allelopatic effects of I. glandulifera on mycorrhizal symbioses were also examined. Allelopatic compounds are known to contribute to the spread of some invasive plant species and can disrupt mycorrhizal symbiosis. I identified the allelopathic compound 2-methoxy-1,4-naphtoquinone (2-MNQ) in plant organs of I. glandulifera, in soil of its proximity and in rain water rinsed from its leaves. Specific bioassays using shoot and root extracts of I. glandulifera as well as synthetic 2-MNQ revealed strong inhibitory effects on mycelium growth of ectomycorrhiza fungi and on the germination of native forest herbs. This finding indicates that the release of 2-MNQ may contribute to the invasion success of I. glandulifera.
Health, function and diversity of forest ecosystems are closely linked to the abundance and richness of mycorrhizal fungi. This study demonstrates that the spread I. glandulifera into deciduous forest ecosystem resulted in lower mycorrhizal colonisation of saplings. Thus, forest regeneration might be strongly affected by I. glandulifera. Moreover, changes in soil chemistry and soil conditions induced by I. glandulifera caused shifts in above- and belowground communities. Therefore ecosystem services and functions of forest habitats can be affected. Removal or stopping the preceding spread of I. glandulifera may be an investment for the conservation of native species and may prevent potential losses in timber production
Milk protein polymorphism in taurine (Bos taurus) and zebu (Bos indicus) populations bred in hot climate
No full textThe genetic variation at four milk protein loci alpha(s1)-casein (CSN1S1), beta-casein (CSN2), kappa-casein (CSN3) and beta-lactoglobulin (LGB) was investigated in 358 animals belonging to seven populations well adapted to hot climatic conditions, reared in Africa and Italy. Bos taurus (Somba, Lagune and Modicana), Bos indicus (Sudanese Zebu Peul, Azaouak and Adamawa), and B. taurus x B. indicus (Borgou) were studied by adapting different molecular methodologies to evaluate their genetic variability. All loci were polymorphic and a new CSN2 synonymous variant, named A(2'), was detected and characterized. Noteworthy differences in the distribution of alleles and haplotypes were observed between zebuine and taurine cattle showing that milk protein polymorphism is suited for discriminating B. taurus from B. indicus efficiently, and also taurine breeds. Milk protein loci, being positively selected loci, can also provide information about the occurrence of germplasm particularly useful for breeding strategies and production improvement
Short communication: Milk protein genetic variation and casein haplotype structure in the Original Pinzgauer cattle
No full textMilk protein genetic polymorphisms are often used for characterizing domesticated mammalian species and breeds, and for studying associations with economic traits. The aim of this work was to analyze milk protein genetic variation in the Original Pinzgauer, a dual-purpose (dairy and beef) cattle breed of European origin that was influenced in the past by human movements from different regions as well as by crossbreeding with Red Holstein. A total of 485 milk samples from Original Pinzgauer from Austria (n=275) and Germany (n=210) were typed at milk proteins alphaS1-casein, beta-casein, kappa-casein, alpha-lactalbumin, and beta-lactoglobulin by isoelectrofocusing to analyze the genetic variation affecting the protein amino acid charge. The Original Pinzgauer breed is characterized by a rather high genetic variation affecting the amino acid charge of milk proteins, with a total of 15 alleles, 12 of which were found at a frequency >0.05. The most polymorphic protein was beta-casein with 4 alleles detected. The prevalent alleles were CSN1S1*B, CSN2*A 2 , CSN1S2*A, CSN3*A, LGB*A, and LAA*B. A relatively high frequency of CSN1S2*B (0.202 in the whole data set) was found, mainly occurring within the C-A 2 -B-A haplotype (in the order CSN1S1-CSN2-CSN1S2-CSN3), which seems to be peculiar to the Original Pinzgauer, possibly because the survival of an ancestral haplotype or the introgression of Bos indicus
A new variant in exon VII of bovine beta-casein gene (CSN2) and its distribution among European breeds
No full textAn undescribed bovine CSN2 variant was detected and characterized. It is based on a mutation in exon VII, which leads to a substitution of the aminoacid 93 (Met→Leu) in comparison to allele CSN*A2. The new allele was named CSN2*I. A PCR-SSCP based DNA-test for the differentiation of the common alleles A1, A2, A3, B, C, and of the new variant I was developed. Genotyping of 318 unrelated animals belonging to seven European breeds (Italian Holstein Friesian, Italian Red Pied, Piemontese, Angler, Maremmana, Polish Red and White, Polish Red) showed a wide distribution of the new variant with a frequency up to 0.14 in Italian Red Pied
Genomics and proteomics of deleted ovine CSN1S1*I
No full textOvine αs1-casein (CSN1S1) allele I (CSN1S1∗I) was characterized at the molecular genetic and protein level. Sequencing of CSN1S1 cDNA and mature protein showed the absence of exon 7 from CSN1S1∗I in comparison with the C′′ genetic variant of the C phenotype. This allelic aberration is correlated with a sequence difference in 5′-splice donor sequence of intron 7 (g.656T > A), leading to upstream skipping of exon 7. Consequently mRNA sequence of ovine CSN1S1∗I is 24 bp shorter than complete coding sequence leading to an abbreviation of eight amino acids in the mature protein, resulting in a lower degree of phosphorylation in comparison with CSN1S1∗C′′. However CSN1S1∗I was expressed at a quantitative level similar to that for the C′′ reference variant. Using amplified created restriction site polymerase chain reaction, a DNA-based test for identification of CSN1S1∗I was developed. Altogether six nucleotide substitutions were identified within intron 6 and intron 7 of CSN1S1 variants, forming three different haplotypes
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