Temporal comparison of greenhouse gas emissions between four different riparian land-use types in southern Ontario, Canada

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Design ethnography in information systems

Until recently, most ethnographic research in information systems has been based on the traditional anthropological model of ethnography. In this traditional model of ethnography, one of the most important data-gathering techniques is participant observation. The ethnographer observes and participates but does not actively seek to change the situation. In recent years, however, a new type of ethnographic research has emerged - one that can be called design ethnography. Design ethnography is where the researcher goes beyond observation and actively engages with people in the field. Our view is that design ethnography has much potential for research in information systems. It is a new form of engaged scholarship that bridges the gap between ethnographic research and design science research

Influence of 100% and 40% oxygen on penumbral blood flow, oxygen level, and T2*-weighted MRI in a rat stroke model

Accurate imaging of the ischemic penumbra is a prerequisite for acute clinical stroke research. T2* magnetic resonance imaging (MRI) combined with an oxygen challenge (OC) is being developed to detect penumbra based on changes in blood deoxyhemoglobin. However, inducing OC with 100% O2 induces sinus artefacts on human scans and influences cerebral blood flow (CBF), which can affect T2* signal. Therefore, we investigated replacing 100% O2 OC with 40% O2 OC (5 minutes 40% O2 versus 100% O2) and determined the effects on blood pressure (BP), CBF, tissue pO2, and T2* signal change in presumed penumbra in a rat stroke model. Probes implanted into penumbra and contralateral cortex simultaneously recorded pO2 and CBF during 40% O2 (n=6) or 100% O2 (n=8) OC. In a separate MRI study, T2* signal change to 40% O2 (n=6) and 100% O2 (n=5) OC was compared. Oxygen challenge (40% and 100% O2) increased BP by 8.2% and 18.1%, penumbra CBF by 5% and 15%, and penumbra pO2 levels by 80% and 144%, respectively. T2* signal significantly increased by 4.56%±1.61% and 8.65%±3.66% in penumbra compared with 2.98%±1.56% and 2.79%±0.66% in contralateral cortex and 1.09%±0.82% and −0.32%±0.67% in ischemic core, respectively. For diagnostic imaging, 40% O2 OC could provide sufficient T2* signal change to detect penumbra with limited influence in BP and CBF

Braided Oscillators

The braided Hopf algebra structure of the generalized oscillator is investigated. Using the solutions two types of braided Fibonacci oscillators are introduced. This leads to two types of braided Biedenharn-Macfarlane oscillators.Comment: 12 pages, latex, some references added, published versio

Molecular dosimetry of 1,2 guanine-guanine intrastrand cross links of cisplatin by ultra performance liquid chromatography tandem mass spectrometry

Cisplatin has been extensively studied as an antitumor agent since the late 1960s. However the mode of action for the efficacy and adverse effects of cisplatin are poorly understood. It was previously believed that the cisplatin1,2 intrastrand guanine-guanine [CP-d(GpG)] cross link was likely responsible for much of the cytotoxic actions of the compound. But current techniques prevented accurate and specific adduct quantification using pharmacologically relevant concentrations of cisplatin. Therefore, the development of a highly sensitive and specific method to measure the CPd( GpG) cross link was begun. Using this technique, this dissertation aimed to study the role of CP-d(GpG) in acquired resistance and different genetic profiles. The developed mass spectrometry method is able to measure 3.7 adducts per 108 nucleotides using 25 μg of DNA per injection. Preliminary results indicated that the method was sensitive enough to quantify adducts in ovarian carcinoma cells using as little as 12.5 μM cisplatin. It was also able to quantify adducts the kidney, liver and colon tissues of mice that had been iii given 7 mg/kg cisplatin by i.p. injection. Our hypothesis was that the density of CP-d(GpG) cross links would serve as a useful biomarker for efficacy and/or toxicity of cisplatin. Research was conducted to understand CPd( GpG) formation in ovarian carcinoma cell lines as well as in 8 inbred strains of mice. Results indicate that the dose response relationship for adduct formation in our isogenic cisplatin sensitive and resistant cell lines remains linear, when using lower more pharmacologically relevant doses of cisplatin. In mice, adducts were most concentrated in the kidney. Of the 8 inbred strains tested the C57BL/6J mice were the most sensitive and FVB/NJ least sensitive to cisplatin treatment. Toxicity, as determined by histopathology, did not correlate with CP-d(GpG) molecular dosimetry. However, this lack of correlation may be due to the design of the mouse study, as such many suggestions for future animal studies are given. Based on reported concentrations of platinum DNA adducts clinical samples, the sensitivity and specificity of our method could provide additional insight as to the role of CPd( GpG) adduct formation in cancer patients being treated with cisplatin

Homology blocks of Plasmodium falciparum var genes and clinically distinct forms of severe malaria in a local population

Abstract Background The primary target of the human immune response to the malaria parasite Plasmodium falciparum, P. falciparum erythrocyte membrane protein 1 (PfEMP1), is encoded by the members of the hyper-diverse var gene family. The parasite exhibits antigenic variation via mutually exclusive expression (switching) of the ~60 var genes within its genome. It is thought that different variants exhibit different host endothelial binding preferences that in turn result in different manifestations of disease. Results Var sequences comprise ancient sequence fragments, termed homology blocks (HBs), that recombine at exceedingly high rates. We use HBs to define distinct var types within a local population. We then reanalyze a dataset that contains clinical and var expression data to investigate whether the HBs allow for a description of sequence diversity corresponding to biological function, such that it improves our ability to predict disease phenotype from parasite genetics. We find that even a generic set of HBs, which are defined for a small number of non-local parasites: capture the majority of local sequence diversity; improve our ability to predict disease severity from parasite genetics; and reveal a previously hypothesized yet previously unobserved parasite genetic basis for two forms of severe disease. We find that the expression rates of some HBs correlate more strongly with severe disease phenotypes than the expression rates of classic var DBLα tag types, and principal components of HB expression rate profiles further improve genotype-phenotype models. More specifically, within the large Kenyan dataset that is the focus of this study, we observe that HB expression differs significantly for severe versus mild disease, and for rosetting versus impaired consciousness associated severe disease. The analysis of a second much smaller dataset from Mali suggests that these HB-phenotype associations are consistent across geographically distant populations, since we find evidence suggesting that the same HB-phenotype associations characterize this population as well. Conclusions The distinction between rosetting versus impaired consciousness associated var genes has not been described previously, and it could have important implications for monitoring, intervention and diagnosis. Moreover, our results have the potential to illuminate the molecular mechanisms underlying the complex spectrum of severe disease phenotypes associated with malaria—an important objective given that only about 1% of P. falciparum infections result in severe disease.http://deepblue.lib.umich.edu/bitstream/2027.42/112650/1/12866_2013_Article_2116.pd

Designing an information system for updating land records in Bangladesh: action design ethnographic research (ADER)

Open Access. This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.This article has been made available through the Brunel Open Access Publishing Fund.Information Systems (IS) has developed through adapting, generating and applying diverse methodologies, methods, and techniques from reference disciplines. Further, Action Design Research (ADR) has recently developed as a broad research method that focuses on designing and redesigning IT and IS in organizational contexts. This paper reflects on applying ADR in a complex organizational context in a developing country. It shows that ADR requires additional lens for designing IS in such a complex organizational context. Through conducting ADR, it is seen that an ethnographic framework has potential complementarities for understanding complex contexts thereby enhancing the ADR processes. This paper argues that conducting ADR with an ethnographic approach enhances design of IS and organizational contexts. Finally, this paper aims presents a broader methodological framework, Action Design Ethnographic Research (ADER), for designing artefacts as well as IS. This is illustrated through the case of a land records updating service in Bangladesh

Instanton vibrations of the 3-Skyrmion

The Atiyah-Drinfeld-Hitchin-Manin matrix corresponding to a tetrahedrally symmetric 3-instanton is calculated. Some small variations of the matrix correspond to vibrations of the instanton-generated 3-Skyrmion. These vibrations are decomposed under tetrahedral symmetry and this decomposition is compared to previous knowledge of the 3-Skyrmion vibration spectrum.Comment: 10 pages, LaTeX, no figures, PRD version with longer introduction and minor change

Symmetric Skyrmions

We present candidates for the global minimum energy solitons of charge one to nine in the Skyrme model, generated using sophisticated numerical algorithms. Assuming the Skyrme model accurately represents the low energy limit of QCD, these configurations correspond to the classical nuclear ground states of the light elements. The solitons found are particularly symmetric, for example, the charge seven skyrmion has icosahedral symmetry, and the shapes are shown to fit a remarkable sequence defined by a geometric energy minimization (GEM) rule. We also calculate the energies and sizes to within at least a few percent accuracy. These calculations provide the basis for a future investigation of the low energy vibrational modes of skyrmions and hence the possibility of testing the Skyrme model against experiment.Comment: latex, 9 pages, 1 figure (fig1.gif