357 research outputs found
Action research and democracy
This contribution explores the relationship between research and learning democracy. Action research is seen as being compatible with the orientation of educational and social work research towards social justice and democracy. Nevertheless, the history of action research is characterized by a tension between democracy and social engineering. In the social-engineering approach, action research is conceptualized as a process of innovation aimed at a specific Bildungsideal. In a democratic approach action research is seen as research based on cooperation between research and practice. However, the notion of democratic action research as opposed to social engineering action research needs to be theorized. So called democratic action research involving the implementation by the researcher of democracy as a model and as a preset goal, reduces cooperation and participation into instruments to reach this goal, and becomes a type of social engineering in itself. We argue that the relationship between action research and democracy is in the acknowledgment of the political dimension of participation: ‘a democratic relationship in which both sides exercise power and shared control over decision-making as well as interpretation’. This implies an open research design and methodology able to understand democracy as a learning process and an ongoing experiment
Uncanny Objects and the Fear of the Familiar:Hiding from Akan Witches in New York City
This article examines the cosmology and secret practices of West African traditional priests in New York City in preventing the spread of witchcraft, an evil invisible spirit transmitted between female members of the Akan matrilineage. Explored is an uncanny dynamic as everyday habitus becomes increasingly strange in the world of a young Ghanaian woman in the Bronx, who has become petrified of insinuations of witchcraft from close family members. In trying to hide the young woman from infection by her fellow witches, Akan priests attempt to ‘capture’ her habits and everyday routines, calling upon the iconic magic of New York City in order to ‘misplace’ familiarity within the anonymity of Manhattan. In this process, the transmission of the witch’s spirit to the intended victim is disturbed as the victim’s life and things are moved. Nowhere to be found, the witch shifts her attention to other victims
Continuous immobilized yeast reactor system for complete beer fermentation using spent grains and corncobs as carrier materials
Despite extensive research carried out in
the last few decades, continuous beer fermentation has not yet managed to outperform the traditional batch technology. An industrial breakthrough in favour of
continuous brewing using immobilized yeast could be expected only on achievement of the following process characteristics: simple design, low investment costs, flexible operation, effective process control and good
product quality. The application of cheap carrier materials of by-product origin could significantly lower the investment costs of continuous fermentation systems.
This work deals with a complete continuous beer fermentation system consisting of a main fermentation reactor (gas-lift) and a maturation reactor (packedbed) containing yeast immobilized on spent grains and
corncobs, respectively. The suitability of cheap carrier materials for long-term continuous brewing was proved. It was found that by fine tuning of process
parameters (residence time, aeration) it was possible to adjust the flavour profile of the final product. Consumers considered the continuously fermented beer to be of a regular quality. Analytical and sensorial profiles of both continuously and batch fermented beers were compared.(Fundação de Amparo a Pesquisa do Estado de São Paulo, Brazil (FAPESPFundação para a Ciência e a Tecnologia (FC
The Clacton Spear: the last one hundred years
In 1911 an eminent amateur prehistorian pulled the broken end of a pointed wooden shaft from Palaeolithic-age sediments at a seaside town in Essex. This artefact, still the earliest worked wood to be discovered in the world, became known as the Clacton Spear. Over the past 100 years it has variously been interpreted as a projectile weapon, a stave, a digging stick, a snow probe, a lance, a game stake and a prod to ward off rival scavengers. These perspectives have followed academic fashions, as the popular views of early hominins have altered. Since discovery the Clacton spear has also been replicated twice, has undergone physical transformations due to preservation treatments, and has featured in two public exhibitions. Within this article the changing context of the spear, its parallels, and all previous conservation treatments and their impacts are assessed.© 2015 Royal Archaeological Institute. This is an Accepted Manuscript of an article published by Taylor & Francis in The Archaeological Journal on 3rd March 2015, available online: http://www.tandfonline.com/doi.org/10.1080/00665983.2015.1008839.The attached document is the author(’s’) final accepted/submitted version of the journal article. You are advised to consult the publisher’s version if you wish to cite from it
Applications of yeast flocculation in biotechnological processes
A review on the main aspects associated with yeast flocculation and its application
in biotechnological processes is presented. This subject is addressed following three
main aspects – the basics of yeast flocculation, the development of “new” flocculating yeast
strains and bioreactor development. In what concerns the basics of yeast flocculation, the
state of the art on the most relevant aspects of mechanism, physiology and genetics of yeast
flocculation is reported. The construction of flocculating yeast strains includes not only the
recombinant constitutive flocculent brewer’s yeast, but also recombinant flocculent yeast
for lactose metabolisation and ethanol production. Furthermore, recent work on the
heterologous β-galactosidase production using a recombinant flocculent Saccharomyces
cerevisiae is considered. As bioreactors using flocculating yeast cells have particular properties,
mainly associated with a high solid phase hold-up, a section dedicated to its operation is
presented. Aspects such as bioreactor productivity and culture stability as well as bioreactor
hydrodynamics and mass transfer properties of flocculating cell cultures are considered.
Finally, the paper concludes describing some of the applications of high cell density
flocculation bioreactors and discussing potential new uses of these systems.Fundação para a Ciência e a Tecnologia (FCT) – PRAXIS XXI - BD11306/97
‘‘Beet-ing’’ the Mountain: A Review of the Physiological and Performance Effects of Dietary Nitrate Supplementation at Simulated and Terrestrial Altitude
Exposure to altitude results in multiple physiological consequences. These include, but are not limited to, a reduced maximal oxygen consumption, drop in arterial oxygen saturation, and increase in muscle metabolic perturbations at a fixed sub-maximal work rate. Exercise capacity during fixed work rate or incremental exercise and time-trial performance are also impaired at altitude relative to sea-level. Recently, dietary nitrate (NO3-) supplementation has attracted considerable interest as a nutritional aid during altitude exposure. In this review, we summarise and critically evaluate the physiological and performance effects of dietary NO3- supplementation during exposure to simulated and terrestrial altitude. Previous investigations at simulated altitude indicate that NO3- supplementation may reduce the oxygen cost of exercise, elevate arterial and tissue oxygen saturation, improve muscle metabolic function, and enhance exercise capacity/ performance. Conversely, current evidence suggests that NO3- supplementation does not augment the training response at simulated altitude. Few studies have evaluated the effects of NO3- at terrestrial altitude. Current evidence indicates potential improvements in endothelial function at terrestrial altitude following NO3- supplementation. No effects of NO3- supplementation have been observed on oxygen consumption or arterial oxygen saturation at terrestrial altitude, although further research is warranted. Limitations of the present body of literature are discussed, and directions for future research are provided
Pentamycin biosynthesis in Philippine Streptomyces sp. S816 : cytochrome P450-catalyzed installation of the C-14 hydroxyl group
Pentamycin is a polyene antibiotic, registered in Switzerland for the treatment of vaginal candidiasis, trichomoniasis, and mixed infections. Chemical instability has hindered its widespread application and development as a drug. Here, we report the identification of Streptomyces sp. S816, isolated from Philippine mangrove soil, as a pentamycin producer. Genome sequence analysis identified the putative pentamycin biosynthetic gene cluster, which shows a high degree of similarity to the gene cluster responsible for filipin III biosynthesis. The ptnJ gene, which is absent from the filipin III biosynthetic gene cluster, was shown to encode a cytochrome P450 capable of converting filipin III to pentamycin. This confirms that the cluster directs pentamycin biosynthesis, paving the way for biosynthetic engineering approaches to the production of pentamycin analogues. Several other Streptomyces genomes were found to contain ptnJ orthologues clustered with genes encoding polyketide synthases that appear to have similar architectures to those responsible for the assembly of filipin III and pentamycin, suggesting pentamycin production may be common in Streptomyces species
Total Synthesis of Kalimantacin A
The kalimantacins make up a family of hybrid polyketide-nonribosomal peptide-derived natural products that display potent and selective antibiotic activity against multidrug resistant strains of Staphylococcus aureus. Herein, we report the first total synthesis of kalimantacin A, in which three fragments are prepared and then united via Sonogashira and amide couplings. The enantioselective synthetic approach is convergent, unlocking routes to further kalimantacins and analogues for structure-activity relationship studies and clinical evaluation.status: publishe
Halloween, Organization, and the Ethics of Uncanny Celebration
This article examines the relationship between organizational ethics, the uncanny, and the annual celebration of Halloween. We begin by exploring the traditional and contemporary organizational function of Halloween as ‘tension-management ritual’ (Etzioni, Sociol Theory 18(1):44–59, 2000) through which collective fears, anxieties, and fantasies are played out and given material expression. Combining the uncanny with the folkloric concept of ostension, we then examine an incident in which UK supermarket retailers made national news headlines for selling offensive Halloween costumes depicting ‘escaped mental patients’. Rather than treating this incident as a problem of moral hygiene—in which products are removed, apologies made, and lessons learned—we consider the value of Halloween as a unique and disruptive ethical encounter with the uncanny Other. Looking beyond its commercial appeal and controversy, we reflect on the creative, generous, and disruptive potential of Halloween as both tension-management ritual and unique organizational space of hospitality through which to receive and embrace alterity and so discover the homely within the unheimlich
Physical characteristics of the back are not predictive of low back pain in healthy workers: A prospective study
Background. In the working population, back disorders are an important reason for sick leave and permanent work inability. In the context of fitting the job to the worker, one of the primary tasks of the occupational health physician is to evaluate the balance between work-related and individual variables. Since this evaluation of work capacity often consists of a physical examination of the back, the objective of this study was to investigate whether a physical examination of the low back, which is routinely performed in occupational medicine, predicts the development of low back pain (LBP). Methods. This study is part of the Belgian Low Back Cohort (BelCoBack) Study, a prospective study to identify risk factors for the development of low back disorders in occupational settings. The study population for this paper were 692 young healthcare or distribution workers (mean age of 26 years) with no or limited back antecedents in the year before inclusion. At baseline, these workers underwent a standardised physical examination of the low back. One year later, they completed a questionnaire on the occurrence of LBP and some of its characteristics. To study the respective role of predictors at baseline on the occurrence of LBP, we opted for Cox regression with a constant risk period. Analyses were performed separately for workers without any back antecedents in the year before inclusion ('asymptomatic' workers) and for workers with limited back antecedents in the year before inclusion ('mildly symptomatic' workers). Results. In the group of 'asymptomatic' workers, obese workers showed a more than twofold-increased risk on the development of LBP as compared to non-obese colleagues (RR 2.57, 95%CI: 1.09 - 6.09). In the group of 'mildly symptomatic' workers, the self-reports of pain before the examination turned out to be most predictive (RR 3.89, 95%CI: 1.20 - 12.64). Conclusion. This study showed that, in a population of young workers wh no or limited antecedents of LBP at baseline, physical examinations, as routinely assessed in occupational medicine, are not useful to predict workers at risk for the development of back disorders one year later
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