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Search Results: 1 - 10 of 1636 matches for " Sarina Keller "
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Scientization: putting global climate change on the scientific agenda and the role of the IPCC
Sarina Keller
Poiesis & Praxis , 2010, DOI: 10.1007/s10202-010-0083-5
Abstract: Since the 1970s, climate change has dominated the international scientific and political agenda. In particular, the foundation of the Intergovernmental Panel on Climate Change at the end of the 1980s played a major role for the further enhancement of efforts in the field of climate change sciences. However, to understand the interaction of the worldwide coordination of climate change sciences as well as the role of the Intergovernmental Panel on Climate Change and its consequences, it is worthwhile to take a look at the self-conception of the Intergovernmental Panel on Climate Change’s tasks and work. This paper gives an idea of the history of international climate change science, its representation in public discourse and the role of the Intergovernmental Panel on Climate Change by comprehensively illustrating its tasks, organization and self-image. Furthermore, the article tries to argue that the hitherto accepted concept of science followed within this body fails to integrate the idea of scientific ethics. It can be concluded that the conception of science represented by the Intergovernmental Panel on Climate Change has heavily influenced worldwide attention to climate change, its becoming part of the political agenda as well as the ethical consequences.
Edges in Agricultural Landscapes: Species Interactions and Movement of Natural Enemies
Sarina Macfadyen, Warren Muller
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0059659
Abstract: Agricultural landscapes can be characterized as a mosaic of habitat patches interspersed with hostile matrix, or as a gradient of patches ranging from suitable to unsuitable for different species. Arthropods moving through these landscapes encounter a range of edges, with different permeability. Patches of native vegetation in these landscapes may support natural enemies of crop pests by providing alternate hosts for parasitic wasps and/or acting as a source for predatory insects. We test this by quantifying species interactions and measuring movement across different edge-types. A high diversity of parasitoid species used hosts in the native vegetation patches, however we recorded few instances of the same parasitoid species using hosts in both the native vegetation and the crop (canola). However, we did find overall greater densities of parasitoids moving from native vegetation into the crop. Of the parasitoid groups examined, parasitoids of aphids (Braconidae: Aphidiinae) frequently moved from native vegetation into canola. In contrast, parasitoids of caterpillars (Braconidae: Microgastrinae) moved commonly from cereal fields into canola. Late season samples showed both aphids and parasitoids moving frequently out of native vegetation, in contrast predators moved less commonly from native vegetation (across the whole season). The season-long net advantage or disadvantage of native vegetation for pest control services is therefore difficult to evaluate. It appears that the different edge-types alter movement patterns of natural enemies more so than herbivorous pest species, and this may impact pest control services.
Effect of Wood Compost on Extreme Soil Characteristics in the Lusatian Lignite Region  [PDF]
Wael Nada, Oswald Blumenstein, Sarina Claassens, Leon van Rensburg
Open Journal of Soil Science (OJSS) , 2012, DOI: 10.4236/ojss.2012.24041

Open-cast lignite mining operations result in a loss of soil quality. Soils associated with coal mining are usually characterised by poor physical and chemical parameters. Low pH and heavy metal toxicity are of the main concerns. The lignite and pyrite content of the dump materials of the Lusatian open-cast mining district in Eastern Germany resulted in high acidification potential and low organic matter content of soils. These extreme conditions require considerable amounts of alkaline materials like compost to enable revegetation. This study was carried out to evaluate the effect of different application rates of wood compost on soil physico-chemical properties in two representative soil substrates (tertiary and quaternary) and on some plant growth parameters. Soil in each site was mixed with wood compost and sown with a grass mixture. The data of both studied soils showed an improvement in physical properties such as water holding capacity and bulk density in soil ameliorated with compost. Most soil chemical properties were increased significantly with the increase of compost application rates, particularly organic matter content, total nitrogen and cation exchange capacity. Compared to the control treatment in each site, the treated soil with compost showed a significant increase in grass biomass (fresh and dry matter yield). The results of these experiments revealed that addition of wood compost had significant positive effects on the soil physical and chemical properties, which affected the response of plant growth and can facilitate the revegetation of substrates contaminated with coal spoil.

Herd Level Antimicrobial Resistance in Beef Calves in Switzerland 1986 through 2011  [PDF]
Michael H?ssig, Sarina Eugster, Frazer Iain Lewis
Open Journal of Veterinary Medicine (OJVM) , 2014, DOI: 10.4236/ojvm.2014.411029

The increasing emergence of antimicrobial resistance in food animals is a growing global concern and is closely linked to animal husbandry practices. In this study we describe the changement of antimicrobial resistance in beef calf production in Switzerland from 1986 through 2011. Data were collected from farms with known calf herd problems, such as diarrhoea or pneumonia, along with antimicrobial resistance from those herds. The Herd Health Section of the University of Zu-rich visited each farm. Samples were analysed for bacterial growth and resistance test commonly indicated in diseases such as calf pneumonia and diarrhoea. Each resistance test comprised of samples from at least three diseased animals. For diarrhoea, a faeces sample was used, for pneu-monia a deep nasal swab was taken. In nasal swabs, only batches yielding considerable bacterial growth in three individual animal samples were included for diagnosis. Other growth of bacteria was considered as contamination. The results consisted of bacterial resistance to antibiotics against defined diseases such as calf diarrhoea and calf pneumonia at herd level. This approach is reflecting the situation as found in practice when a calf has to be treated without delay and without results from further laboratory diagnostics. In diarrhoea cases, four antibiotics showed no bacterial resistance. Bacterial resistance of below 10% was observed to three antibiotics. Up to 20% bacterial resistance was found to two antibiotics. Eighty per cent and over was found to be six antibiotics. Bacterial resistance to two antibiotics was found in over 90% of samples and all samples were resistant to one antibiotic. In pneumonia three antibiotics showed no resistance; one was below 10%; four antibiotics were below 20%. Over 80% of samples were resistant to four antibiotics. One resistance was over 90% and all bacterial samples were resistant to two antibiotics. Differences in bacterial resistance between pneumonia and diarrhoea in two study periods with equal cases, i.e. 1986-2006 and 2007-2011 were found. A reduction in bacterial resistance can be found in 5 out of 7 cases, when the amount of the respective antibiotic was reduced over time. This finding raises the obvious question whether antibiotics should be removed from the marked ones by a period of about 10 years. This would help to control not only bacterial resistance but also the use of the limited amount of antimicrobial drugs available. Such a control program would need to be established by

Evidence-Based Use of Antibiotics in Meat Calves  [PDF]
Michael H?ssig, Sarina Eugster, Fraser Iain Lewis
Open Journal of Veterinary Medicine (OJVM) , 2015, DOI: 10.4236/ojvm.2015.53009
Abstract: Abuse of antibiotics is an increasing commonly feature in the media. Widespread preventive use of antibiotics without diagnostics in meat calf husbandry is a major public health concern. In this study, we compare a “trial and error” method, comprising of a first choice antibiotic, followed by a second and third choice (as recommended by the WHO), with a method which utilizes an antibiotic resistance test to first identify the best antibiotic out of first, second or third choice alternatives using decision tree analysis. Data were collected from farms with a known calf herd problem along with antibiograms from those herds. Samples were analysed for resistance to antibiotics against calf pneumonia on a herd level, rather than for resistance against specific antibiotics. Resistance tests were performed on batch samples composed of at least three diseased animals. A deep nasal swap was taken. In nasal swaps only ++ or +++ growth in all 3 samples were used for diagnosis. Other growth of bacteria was considered as contamination. A comparison of resistance rates across a range of antibiotics between farms with known calf pneumonia and calf diarrhoea issues was performed. The decision tree analysis presented provides strong support in favour of an evidence-based approach to antimicrobial treatment by using an antimicrobial resistance test, providing an advantage of 58% per meat calf against the “trial and error” method, giving a financial gain of some CHF 320.09 under Swiss economic circumstances.
Modelling the Geographical Range of a Species with Variable Life-History
Sarina Macfadyen, Darren J. Kriticos
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0040313
Abstract: We show how a climatic niche model can be used to describe the potential geographic distribution of a pest species with variable life-history, and illustrate how to estimate biogeographic pest threats that vary across space. The models were used to explore factors that affect pest risk (irrigation and presences of host plant). A combination of current distribution records and published experimental data were used to construct separate models for the asexual and sexual lineages of Rhopalosiphum padi (Linnaeus) (Hemiptera: Aphididae). The two models were combined with knowledge of host plant presence to classify the global pest risk posed by R. padi. Whilst R. padi has a relatively limited area in which sexual lineages can persist year round, a much larger area is suitable for transient sexual and asexual lineages to exist. The greatest risk of establishment of persistent sexual and asexual populations is in areas with warm temperate climates. At the global scale the models show very little difference in risk patterns between natural rainfall and irrigation scenarios, but in Australia, the amount of land suitable for persistent asexual and transient sexual populations decreases (by 20%) if drought stress is no longer alleviated by irrigation. This approach proved useful for modelling the potential distribution of a species that has a variable life-history. We were able to use the model outputs to examine factors such as irrigation practices and host plant presence that altered the nature (transient or permanent) and extent of pest risk. The composite niche maps indicate pest risk in terms that are useful to both biosecurity agencies and pest managers.
Receptor Tyrosine Kinases: Molecular Switches Regulating CNS Axon Regeneration
Vasanthy Vigneswara,Sarina Kundi,Zubair Ahmed
Journal of Signal Transduction , 2012, DOI: 10.1155/2012/361721
Abstract: The poor or lack of injured adult central nervous system (CNS) axon regeneration results in devastating consequences and poor functional recovery. The interplay between the intrinsic and extrinsic factors contributes to robust inhibition of axon regeneration of injured CNS neurons. The insufficient or lack of trophic support for injured neurons is considered as one of the major obstacles contributing to their failure to survive and regrow their axons after injury. In the CNS, many of the signalling pathways associated with neuronal survival and axon regeneration are regulated by several classes of receptor tyrosine kinases (RTK) that respond to a variety of ligands. This paper highlights and summarises the most relevant recent findings pertinent to different classes of the RTK family of molecules, with a particular focus on elucidating their role in CNS axon regeneration. 1. Introduction In the mammalian central nervous system (CNS), the failure of spontaneous regeneration of injured axons leads to devastating consequences and poor functional recovery. Severe injuries to CNS axons not only damage plasticity of synapses but also provoke complex degenerative cascades, leading to glial and neuronal apoptosis. The vast majority of injured CNS neurons progressively fails to regenerate beyond the lesion site to reestablish functional synaptic transmission and only a small number of axons show compensatory sprouting, resulting in poor functional recovery [1–5]. Lack or insufficient trophic support is one of the major determinants attributed to the failure of adult CNS axon regeneration. Growth factors that act both on neurons and glia, mediate a variety of physiological functions from early embryonic to the adult state, including synaptic plasticity, cell survival, and death in the CNS [6–10]. Hence, trophic factors and their corresponding receptor-mediated signalling pathways involved in neuronal survival and axon regeneration have been subjected to considerable attention. Many of these studies have been aimed at developing potential therapeutic interventions for the treatment of peripheral nervous system (PNS) and CNS injuries and certain neurodegenerative disorders like Parkinson’s and Alzheimer’s diseases. 2. Mechanisms behind the Failure of CNS Axon Regeneration In general, functional axon regeneration is a multifactorial process; a myriad of molecules and a combination of signalling pathways are often involved. Two important prerequisites are essential for successful regeneration. Firstly, the injured neurons must be competent to survive after injury,
Perfil epidemiológico da coqueluche no Rio Grande do Sul, Brasil: estudo da correla??o entre incidência e cobertura vacinal
Trevizan, Sarina;Coutinho, Simone Elizabeth Duarte;
Cadernos de Saúde Pública , 2008, DOI: 10.1590/S0102-311X2008000100009
Abstract: an upward trend was observed in pertussis incidence in the state of rio grande do sul, brazil, since 2000, leading to an epidemic alert in 2004, based on epidemiological bulletins issued by government health agencies. our objective in the current study was to identify the epidemiological profile of pertussis in the state. we used the incidence of reports of the disease from january 1995 to december 2004, the percentage of vaccine coverage, and characterization of the affected population. a control diagram was constructed to determine the magnitude of the disease in 2004. to analyze the correlation between incidence and vaccine coverage, we established the fluctuation between the vaccine coverage and case reporting in the last ten years. in rio grande do sul, pertussis was on an epidemic level in 2004, representing an important cause of morbidity and mortality in infants (< l year), despite the availability of effective vaccines and high vaccine coverage rates in recent years. studies are thus needed on the disease pattern in the coming years in order to determine the factors involved in this resurgence.
Precariza o e individualiza o: em que sociedade vivemos?: Reflex es sobre a validade empírica do "discurso sobre a segunda modernidade"
Thole, Werner,Ahmed, Sarina,H?blich, Davina
Civitas , 2007,
MicroRNAs as Potential Biomarkers in Acute Promyelocytic Leukaemia
Imilia Ismail,Sarina Sulong,Rosline Hassan
New Journal of Science , 2014, DOI: 10.1155/2014/932342
Abstract: Acute promyelocytic leukaemia (APL) is an M3 subtype of acute myeloid leukaemia (AML). This classification is based on the morphology of promyelocytic cell. The clinical characteristics of APL can be recognized by haemorrhagic episodes, a differentiation block at the promyelocytic stage, and sensitivity to the differentiation response to all-trans-retinoic acid (ATRA). Cytogenetically, APL is characterized by a balanced reciprocal translocation between chromosomes 15 and 17, which results in the production of PML/RARα fusion protein. Recent studies reported that microRNAs (miRNAs) have also been proposed to contribute to the pathogenesis of APL. miRNAs have been associated with the pathogenesis of cancer and their involvement as oncogenic and tumour suppressor activities have been identified. They are involved in various biological processes including the cell proliferation, differentiation, growth and development, metabolism, apoptosis, and haematopoiesis. The new discovery of miRNAs as possible therapeutic markers will provide new insight for the diagnosis and therapeutic entries for the treatment of APL. This review highlights the potential of miRNAs as biomarkers in APL. 1. Introduction Acute promyelocytic leukaemia (APL) is identified as the M3 subtype of acute myeloid leukaemia (AML) by the French-American-British (FAB) classification. This classification is based on the percentage of maturing cells beyond the myeloblast stage. Bone marrow shows hypercellular promyelocytes and the most striking feature of these cells is the cytoplasmic hypergranularity. Multiple Auer rods are also observed in a few early cells in APL. According to WHO 2008 classification, APL is characterized by a reciprocal translocation between chromosomes 15 and 17, which results in the fusion between the promyelocytic leukaemia (PML) gene and retinoic acid receptor α (RARα) gene [1]. A schematic representation of the chromosomes and genes involved in t(15;17) is shown in Figure 1. Figure 1: Chromosomal reciprocal translocation of the 15th and 17th chromosomes. The breakpoints on chromosome 17 are consistently located within the second intron of the RARα gene, but, on chromosome 15, there are different breakpoint cluster regions, namely bcr1, bcr2, and bcr3 located in intron 6, exon 6, and intron 3, respectively, of the PML gene [2, 3]. The location of bcr1, bcr2, and bcr3 produces fusion transcripts of varying lengths referred to as the long, variant, and short forms, respectively [3]. This translocation can be detected by karyotyping or fluorescence in situ hybridization
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