25 research outputs found
The different roles of ‘design process champions’ for digital libraries in African higher education
The concept of design stakeholders is central to effective design of digital libraries. We report on research findings that identified the presence of a key subset of stakeholders which we term ‘design process champions’. Our findings have identified that these champions can change interaction patterns and the eventual output of the other stakeholders (project participants) in the design process of digital library projects. This empirical research is based upon 38 interviews with key stakeholders and a review of documentary evidence in ten innovative digital library design projects (e.g. mobile clinical libraries) located in three African universities in Kenya, Uganda and South Africa. Through a grounded theory approach two different types of the ‘design process champions’ emerged from the data with varying levels of effectiveness in the design process: (i) domain champions and (ii) multidisciplinary champions. The domain champions assume a ‘siloed’ approach of engagement while the multidisciplinary champions take on a participatory engagement throughout the design process. A discussion of the implications of information specialists functioning as domain champions is highlighted. We conclude by suggesting that the multidisciplinary champions’ approach is particularly useful in supporting sustainability of digital library design projects
Mapping and identification of candidate loci responsible for Peromyscus hybrid overgrowth
Crosses between two recently diverged rodent species of the genus Peromyscus result in dramatic parent-of-origin effects on growth and development. P. maniculatus females crossed with P. polionotus males yield growth-retarded conceptuses, whereas the reciprocal cross results in overgrowth and lethality. These hybrid effects are particularly pronounced in the placenta. We previously detected linkage to two regions of the genome involved in the overgrowth effects. One locus, termed Peal, is a paternally expressed autosomal locus mapping to a domain whose house mouse equivalent contains several clusters of imprinted genes. The other locus, termed Mexl, maps to a gene-poor region of the X chromosome. Here we use an advanced intercross line to verify and narrow the regions of linkage and identify candidate genes for Mexl and Peal. While we have previously shown that Mexl affects both pre-and postnatal growth, we show here that Peal affects only prenatal growth. Utilizing criteria such as mutant phenotypes and allelic expression, we identify the loci encoding the homeobox protein Esx1 and the zinc-finger protein Pw1/Peg3 as candidates. Both loci exhibit expression changes in the hybrids
Sequencing and Comparative Genome Analysis of Two Pathogenic Streptococcus gallolyticus Subspecies: Genome Plasticity, Adaptation and Virulence
Streptococcus gallolyticus infections in humans are often associated with bacteremia, infective endocarditis and colon cancers. The disease manifestations are different depending on the subspecies of S. gallolyticus causing the infection. Here, we present the complete genomes of S. gallolyticus ATCC 43143 (biotype I) and S. pasteurianus ATCC 43144 (biotype II.2). The genomic differences between the two biotypes were characterized with comparative genomic analyses. The chromosome of ATCC 43143 and ATCC 43144 are 2,36 and 2,10 Mb in length and encode 2246 and 1869 CDS respectively. The organization and genomic contents of both genomes were most similar to the recently published S. gallolyticus UCN34, where 2073 (92%) and 1607 (86%) of the ATCC 43143 and ATCC 43144 CDS were conserved in UCN34 respectively. There are around 600 CDS conserved in all Streptococcus genomes, indicating the Streptococcus genus has a small core-genome (constitute around 30% of total CDS) and substantial evolutionary plasticity. We identified eight and five regions of genome plasticity in ATCC 43143 and ATCC 43144 respectively. Within these regions, several proteins were recognized to contribute to the fitness and virulence of each of the two subspecies. We have also predicted putative cell-surface associated proteins that could play a role in adherence to host tissues, leading to persistent infections causing sub-acute and chronic diseases in humans. This study showed evidence that the S. gallolyticus still possesses genes making it suitable in a rumen environment, whereas the ability for S. pasteurianus to live in rumen is reduced. The genome heterogeneity and genetic diversity among the two biotypes, especially membrane and lipoproteins, most likely contribute to the differences in the pathogenesis of the two S. gallolyticus biotypes and the type of disease an infected patient eventually develops
A systematic review of the reporting of Data Monitoring Committees' roles, interim analysis and early termination in pediatric clinical trials
<p>Abstract</p> <p>Background</p> <p>Decisions about interim analysis and early stopping of clinical trials, as based on recommendations of Data Monitoring Committees (DMCs), have far reaching consequences for the scientific validity and clinical impact of a trial. Our aim was to evaluate the frequency and quality of the reporting on DMC composition and roles, interim analysis and early termination in pediatric trials.</p> <p>Methods</p> <p>We conducted a systematic review of randomized controlled clinical trials published from 2005 to 2007 in a sample of four general and four pediatric journals. We used full-text databases to identify trials which reported on DMCs, interim analysis or early termination, and included children or adolescents. Information was extracted on general trial characteristics, risk of bias, and a set of parameters regarding DMC composition and roles, interim analysis and early termination.</p> <p>Results</p> <p>110 of the 648 pediatric trials in this sample (17%) reported on DMC or interim analysis or early stopping, and were included; 68 from general and 42 from pediatric journals. The presence of DMCs was reported in 89 of the 110 included trials (81%); 62 papers, including 46 of the 89 that reported on DMCs (52%), also presented information about interim analysis. No paper adequately reported all DMC parameters, and nine (15%) reported all interim analysis details. Of 32 trials which terminated early, 22 (69%) did not report predefined stopping guidelines and 15 (47%) did not provide information on statistical monitoring methods.</p> <p>Conclusions</p> <p>Reporting on DMC composition and roles, on interim analysis results and on early termination of pediatric trials is incomplete and heterogeneous. We propose a minimal set of reporting parameters that will allow the reader to assess the validity of trial results.</p
Pan-cancer analysis of whole genomes
Cancer is driven by genetic change, and the advent of massively parallel sequencing has enabled systematic documentation of this variation at the whole-genome scale(1-3). Here we report the integrative analysis of 2,658 whole-cancer genomes and their matching normal tissues across 38 tumour types from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). We describe the generation of the PCAWG resource, facilitated by international data sharing using compute clouds. On average, cancer genomes contained 4-5 driver mutations when combining coding and non-coding genomic elements; however, in around 5% of cases no drivers were identified, suggesting that cancer driver discovery is not yet complete. Chromothripsis, in which many clustered structural variants arise in a single catastrophic event, is frequently an early event in tumour evolution; in acral melanoma, for example, these events precede most somatic point mutations and affect several cancer-associated genes simultaneously. Cancers with abnormal telomere maintenance often originate from tissues with low replicative activity and show several mechanisms of preventing telomere attrition to critical levels. Common and rare germline variants affect patterns of somatic mutation, including point mutations, structural variants and somatic retrotransposition. A collection of papers from the PCAWG Consortium describes non-coding mutations that drive cancer beyond those in the TERT promoter(4); identifies new signatures of mutational processes that cause base substitutions, small insertions and deletions and structural variation(5,6); analyses timings and patterns of tumour evolution(7); describes the diverse transcriptional consequences of somatic mutation on splicing, expression levels, fusion genes and promoter activity(8,9); and evaluates a range of more-specialized features of cancer genomes(8,10-18).Peer reviewe
Vampires in the village Žrnovo on the island of Korčula: following an archival document from the 18th century
Središnja tema rada usmjerena je na raščlambu spisa pohranjenog u Državnom arhivu u Mlecima (fond: Capi del Consiglio de’ Dieci: Lettere di Rettori e di altre cariche) koji se odnosi na događaj iz 1748. godine u korčulanskom selu Žrnovo, kada su mještani – vjerujući da su se pojavili vampiri – oskvrnuli nekoliko mjesnih grobova. U radu se podrobno iznose osnovni podaci iz spisa te rečeni događaj analizira u širem društvenom kontekstu i prate se lokalna vjerovanja.The main interest of this essay is the analysis of the document from the State Archive in Venice (file: Capi del Consiglio de’ Dieci: Lettere di Rettori e di altre cariche) which is connected with the episode from 1748 when the inhabitants of the village Žrnove on the island of Korčula in Croatia opened tombs on the local cemetery in the fear of the vampires treating.
This essay try to show some social circumstances connected with this event as well as a local vernacular tradition concerning superstitions
A new Gambierdiscus species (Dinophyceae) from Rarotonga, Cook Islands: Gambierdiscus cheloniae sp. nov
© 2016 Elsevier B.V. Ciguatera fish poisoning (CFP) has been reported for many years in Rarotonga, Cook Islands, and has had the world's highest reported incidence of this illness for the last 20 years. Following intensive sampling to understand the distribution of the causative organisms of CFP, an undescribed Gambierdiscus species was isolated from the Rarotongan lagoon. Gambierdiscus cheloniae sp. nov. has the common Gambierdiscus Kofoidian plate formula (except for a variability in the number of precingular plates in aberrant cells): Po, 3′, 6″ (7″), 6C?, 6 or 7S, 5′″, 1p and 2″″. The 2′ plate is hatchet shaped and the dorsal end of 1p is pointed and the relatively narrow 1p plate. Morphologically G. cheloniae is similar to the genetically closely related species G. pacificus, G. toxicus and G. belizeanus, although smaller (depth and length) than G. toxicus. The apical pore plate varies from those of G. belizeanus and G. pacificus, which are shorter and narrower, and from G. toxicus, which is larger. G. cheloniae also differs from G. pacificus in the shape of the 2′ plate. The description of this new species is supported by phylogenetic analyses using three different gene regions. G. cheloniae produced the putative maitotoxin-3 analogue, MTX-3, but neither maitotoxin or monitored ciguatoxin. Extracts of G. cheloniae were shown to be highly toxic to mice by intraperitoneal (i.p.) injection, although they were less toxic by gavage. It is possible that this species produces toxins other than putative MTX-3
A new species of Gambierdiscus (Dinophyceae) from the south-west Pacific: Gambierdiscus honu sp. nov.
© 2017 Elsevier B.V. Two isolates of a new tropical, epiphytic dinoflagellate species, Gambierdiscus honu sp. nov., were obtained from macroalgae sampled in Rarotonga, Cook Islands, and from North Meyer Island, Kermadec Islands. Gambierdiscus honu sp. nov. had the common Gambierdiscus Kofoidian plate formula: Po, 3′, 6″, 6C?, 6 or 7S, 5‴, 1p and 2⁗. The characteristic morphological features of this species were its relatively small short dorsoventral length and width and the shape of individual plates, in particular the combination of the hatchet-shaped 2′ and pentagonal 3′ plates and the length to width ratio of the antapical 1p plate. The combination of these characteristics plus the smooth thecal surface and equal sized 1⁗ and 2⁗ plates differentiated this species from other Gambierdiscus species. The phylogenetic analyses supported the unique description. Both isolates of G. honu produced the putative maitotoxin (MTX)-3 analogue, but neither produced ciguatoxin (CTX) or MTX. Extracts of G. honu were shown to be highly toxic to mice by intraperitoneal injection (0.2 mg/kg), although less toxic by gavage. It is possible that toxins other than putative MTX-3 are produced