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The time course of the transcriptomic response of Sinorhizobium meliloti 1021 following a shift to acidic pH
Get PDFHellweg C, Pühler A, Weidner S. The time course of the transcriptomic response of Sinorhizobium meliloti 1021 following a shift to acidic pH. BMC MICROBIOLOGY. 2009;9(1):37
Identification and characterisation of novel iron acquisition mechanisms in Sinorhizobium meliloti 2011 and Pseudomonas aeruginosa
Get PDFAll known microorganisms with the exception of lactobacilli display an absolute requirement for iron. Although iron is the fourth most abundant element on earth, it is rapidly oxidised at neutral pH forming insoluble hydroxides. To overcome this limitation, microorganisms have developed a plethora of mechanisms to acquire iron. Sinorhizobium meliloti 2011, the endosymbiont of Medicago sativa, produces one known siderophore, rhizobactin 1021. Due to the high demand for iron in the nodule, the iron acquisition mechanisms of S. meliloti 2011 have been subject to particular interest.
Rhizobactin 1021 is structurally similar to aerobactin, which is produced by various pathogenic bacteria In E. coli, aerobactin is transported at the inner membrane via the fhu system. The jhu system of E. coli was found to be sufficient to allow the transport of rhizobactin 1021 accross the inner membrane. A fhuC mutant was found to be defective in the transport of rhizobactin 1021. A novel permease, RhtX, was identified in S. meliloti and found to be involved in rhizobactin 1021 transport. Heterologous expression of RhtX in an E. coli JhuC mutant restored rhizobactin 1021 utilisation, but not aerobactin utilisation. A homologue of RhtX was identified in the opportunistic human pathogen P. aeruginosa. Mutation of the gznQ,fptX, was found to result in a deficiency in pyochelin utilisation in P. aeruginosa.
P. aeruginosa was found to be capable of utilising the xenosiderophores rhizobactin 1021, schizokinen and aerobactin. A receptor mediating the transport of these siderophores was identified and characterised.
S. meliloti 2011 has also been found to be capable of acquiring iron from haem compounds, a characteristic generally found only amongst pathogens. A number of putative haem acquisition loci were identified in S. meliloti 2011 and were subject to analyses. The protein encoded by Smc02726 was identified as the receptor for haemin and haemoglobin under free living conditions
OBCH0001 - OBCH0001 Bodhgayā stone stele with a Chinese inscription dated CE 1021-22
No full textBodhgayā stone stele (OBCH0001) with a Chinese inscription (INCH0001) dated CE 1021-22
recensione di H. Solomon, The Rise of Robert Dodsley: Creating the New Age of Print, Carbondale, Ill. Southern Illinois University Press, 1996, in «Rivista storica italiana», CXI, f. III, settembre 1999, pp. 1021-1032
No full textRecensione pubblicata su «Rivista storica italiana», CXI, f. III, settembre 1999, pp. 1021-103
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
. 1021 Año 21 (2022) marzo. El Tlacuache
No full textLa vida cotidiana de los diferentes pueblos de nuestro país se ha visto transformada desde hace dos años debido a la declaratoria, por parte de la Organización Mundial de la Salud, por la pandemia de SARS-COV2. Sin embargo, la vida dentro de las comunidades de origen y tradición indígena siguió su curso con ciertas adaptaciones en sus ciclos rituales, los cuales representan para éstas un mecanismo de cohesión y reafirmación de su identidad como grupo.- El señor de Mazatepec
y la feria en su honor Transformación y continuidad en el poniente de Morelos por Erandy Toledo Alvarado.Las mandas en el Santuario, Mazatepec, Morelos. Marzo 2018. Crédito: Erandy Toledo Alvarado. “Fachada”. Templo del Señor del Calvario (Mazatepec) Estado de Morelos, México, julio 2011. Álbum 2608. Crédito: Catedrales e Iglesias. CC BY 2.0. https://bit.ly/3qnIF71Von Mentz, Brígida (1988), Pueblos de indios, mulatos y mestizos 1770-1870. Los campesinos y las transformaciones protoindustriales en el poniente de Morelos, Ediciones Casa chata/CIESAS, México.ication and Dating. Historical Archaeology. Vol. 36, No.2:111-127
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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