453 research outputs found

    Patterns of antimicrobial susceptibility among bacterial pathogens in South Africa

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    Product Service System Innovation in the Smart City

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    Product service systems (PSS) may usefully form part of the mix of innovations necessary to move society toward more sustainable futures. However, despite such potential, PSS implementation is highly uneven and limited. Drawing on an alternate socio-technical perspective of innovation, this paper provides fresh insights, on among other things the role of context in PSS innovation, to address this issue. Case study research is presented focusing on a use orientated PSS in an urban environment: the Copenhagen city bike scheme. The paper shows that PSS innovation is a situated complex process, shaped by actors and knowledge from other locales. It argues that further research is needed to investigate how actors interests shape PSS innovation. It recommends that institutional spaces should be provided in governance landscapes associated with urban environments to enable legitimate PSS concepts to co-evolve in light of locally articulated sustainability principles and priorities

    Factors associated with missed and delayed DTP3 vaccination in children aged 12 - 59 months in two communities in South Africa, 2012 - 2013

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    Background. Although immunisation services are available to all children in South Africa (SA), many children miss or have delays in receiving vaccines. There are limited data on factors associated with missed or delayed vaccination in children in this setting. Objectives. To assess vaccination coverage and factors associated with missed and delayed diphtheria-tetanus-pertussis vaccine third dose (DTP3) vaccination in children aged 12 - 59 months in two SA communities. Methods. We used data from household-level healthcare utilisation surveys conducted in Soweto in 2012 and in Pietermaritzburg in 2013. Information on vaccination status was recorded from the Road to Health cards or vaccination history from clinics for children aged <5 years. Factors associated with missed or delayed DTP3 vaccination were assessed using unconditional logistic regression. Results. Of a total of 847 eligible children aged 12 - 59 months, 716 had available vaccination information. Overall DTP3 vaccination coverage was high for both sites: 90.6% in Pietermaritzburg and 93.9% in Soweto. However, 32.6% and 25.2% of DTP3 vaccinations were delayed (received after 18 weeks of age) in Pietermaritzburg and Soweto, respectively. The median delay for DTP3 vaccinations was 4.7 weeks (interquartile range 1.7 - 23.0). Factors associated with delayed DTP3 vaccination included being born in 2010 (adjusted odds ratio (aOR) 3.0, 95% confidence interval (CI) 1.4 - 6.3) or 2011 (aOR 2.7, 95% CI 1.3 - 5.7) compared with being born in 2008, probably due to vaccine shortages; a low level of education of the primary caregiver, with children whose caregivers had completed secondary education having lower odds of delayed vaccination (aOR 0.5, 95% CI 0.3 - 0.9) than children whose caregivers only had primary education; and maternal HIV status, with unknown status (aOR 3.5, 95% CI 1.6 - 7.6) associated with higher odds of delay than positive status. Factors associated with missed DTP3 vaccination (not vaccinated by 12 months of age) included two or more children aged <5 years in a household (aOR 2.4, 95% CI 1.2 - 4.9) compared with one child, and household monthly income <ZAR500 (aOR 3.4, 95% CI 1.1 - 11.4) compared with ≥ZAR2 000. Conclusions. Despite high overall DTP3 coverage observed in two communities, many vaccinations were delayed. Vulnerable groups identified in this study should be targeted with improved vaccination services to enhance uptake and timeliness of vaccination

    Perspectives for the VITO beam line at ISOLDE, CERN

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    By using polarized ion beams in combination with the β-NMR technique, the Versatile Ion-polarized Techniques On-line (VITO) experiment at ISOLDE, CERN links together expertise from different fields in an unique experimental setup. An overview of the experimental techniques and a general description of the newly designed beam line are presented. Potential uses in multidisciplinary research and perspectives for future experiments are discussed

    In-source laser spectroscopy with the laser ion source and trap: first direct study of the ground-state properties of Po-217,Po-219

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    D. A. Fink et al.; 15 págs.; 17 figs.; 3 tabs.; Open Access funded by Creative Commons Atribution Licence 3.0A Laser Ion Source and Trap (LIST) for a thick-target, isotope-separation on-line facility has been implemented at CERN ISOLDE for the production of pure, laser-ionized, radioactive ion beams. It offers two modes of operation, either as an ion guide, which performs similarly to the standard ISOLDE resonance ionization laser ion source (RILIS), or as a more selective ion source, where surface-ionized ions from the hot ion-source cavity are repelled by an electrode, while laser ionization is done within a radiofrequency quadrupole ion guide. The first physics application of the LIST enables the suppression of francium contamination in ion beams of neutron-rich polonium isotopes at ISOLDE by more than 1000 with a reduction in laser-ionization efficiency of only 20. Resonance ionization spectroscopy is performed directly inside the LIST device, allowing the study of the hyperfine structure and isotope shift of 217Po for the first time. Nuclear decay spectroscopy of 219Po is performed for the first time, revealing its half-life, α- to-β-decay branching ratio, and α-particle energy. This experiment demonstrates the applicability of the LIST at radioactive ion-beam facilities for the production and study of pure beams of exotic isotopes. Published by the American Physical SocietyThis work was supported by the Bundesministerium für Bildung und Forschung (BMBF, Germany) within the Wolfgang- Gentner programme as well as through the consecutive project fundings of 06Mz9181I, 06Mz7177D, and 05P12UMCIA, by FWO-Vlaanderen (Belgium), by GOA/2010/010 (BOF-KULeuven), by the IUAP-Belgian State Belgian Science Policy (BRIX network P7/12), by the U.K. Science and Technology Facilities Council (STFC), by the European Union within FP7 (ENSAR No. 262010), by the Slovak Research and Development Agency (Contract No. APVV-0105-10), by the Slovak grant agency VEGA, and the Reimei Foundation of JAEA (Contract No. 1/0576/13). T. E. C. was supported by STFC Ernest Rutherford Grant No. ST/J004189/1.Peer Reviewe

    Imputing direct and indirect vaccine effectiveness of childhood pneumococcal conjugate vaccine against invasive disease by surveying temporal changes in nasopharyngeal pneumococcal colonization

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    The limited capabilities in most low-middle income countries to study the benefit of pneumococcal conjugate vaccine (PCV) against invasive pneumococcal disease (IPD), calls for alternate strategies to assess this. We used a mathematical model, to predict the direct and indirect effectiveness of PCV by analyzing serotype specific colonization prevalence and IPD incidence prior to and following childhood PCV immunization in South Africa. We analyzed IPD incidence from 2005-2012 and colonization studies undertaken in HIV-uninfected and HIV-infected child-mother dyads from 2007-2009 (pre-PCV era), in 2010 (7-valent PCV era) and 2012 (13-valent PCV era). We compared the model-predicted to observed changes in IPD incidence, stratified by HIV-status in children >3 months to 5 years and also in women aged >18-45 years. We observed reductions in vaccine-serotype colonization and IPD due to vaccine serotypes among children and women after PCV introduction. Using the changes in vaccine-serotype colonization data, the model-predicted changes in vaccine-serotype IPD incidence rates were similar to the observed changes in PCV-unvaccinated children and adults, but not among children <24 months. Surveillance of colonization prior and following PCV use can be used to impute PCVs' indirect associations in unvaccinated age groups, including in high HIV-prevalence settings

    Conserved Mutations in the Pneumococcal Bacteriocin Transporter Gene, blpA, Result in a Complex Population Consisting of Producers and Cheaters

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    All fully sequenced strains of Streptococcus pneumoniae possess a version of the blp locus, which is responsible for bacteriocin production and immunity. Activation of the blp locus is stimulated by accumulation of the peptide pheromone, BlpC, following its secretion by the ABC transporter, BlpA. The blp locus is characterized by significant diversity in blpC type and in the region of the locus containing putative bacteriocin and immunity genes. In addition, the blpA gene can represent a single large open reading frame or be divided into several smaller fragments due to the presence of frameshift mutations. In this study, we use a collection of strains with blp-dependent inhibition and immunity to define the genetic changes that bring about phenotypic differences in bacteriocin production or immunity. We demonstrate that alterations in blpA, blpC, and bacteriocin/immunity content likely play an important role in competitive interactions between pneumococcal strains. Importantly, strains with a highly conserved frameshift mutation in blpA are unable to secrete bacteriocins or BlpC, but retain the ability to respond to exogenous peptide pheromone produced by cocolonizing strains, stimulating blp-mediated immunity. These “cheater” strains can only coexist with bacteriocin-producing strains that secrete their cognate BlpC and share the same immunity proteins. The variable outcome of these interactions helps to explain the heterogeneity of the blp pheromone, bacteriocin, and immunity protein content
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