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Search: WFRF:(Richardson D.) > (2005-2009)

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  • Yao, W-M, et al. (author)
  • Review of Particle Physics
  • 2006
  • In: Journal of Physics G: Nuclear and Particle Physics. - : IOP Publishing. - 0954-3899 .- 1361-6471. ; 33:1, s. 1-1
  • Journal article (peer-reviewed)
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  • Amsler, C., et al. (author)
  • Review of particle physics
  • 2008
  • In: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 667:1-5, s. 1-1
  • Research review (peer-reviewed)abstract
    • This biennial Review summarizes much of particle physics. Using data from previous editions., plus 2778 new measurements from 645 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We also summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, and supersymmetric particles. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as the Standard Model, particle detectors., probability, and statistics. Among the 108 reviews are many that are new or heavily revised including those on CKM quark-mixing matrix, V-ud & V-us, V-cb & V-ub, top quark, muon anomalous magnetic moment, extra dimensions, particle detectors, cosmic background radiation, dark matter, cosmological parameters, and big bang cosmology.
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5.
  • Tuskan, G A, et al. (author)
  • The genome of black cottonwood, Populus trichocarpa (Torr. & Gray).
  • 2006
  • In: Science. - : American Association for the Advancement of Science (AAAS). - 1095-9203 .- 0036-8075. ; 313:5793, s. 1596-604
  • Journal article (peer-reviewed)abstract
    • We report the draft genome of the black cottonwood tree, Populus trichocarpa. Integration of shotgun sequence assembly with genetic mapping enabled chromosome-scale reconstruction of the genome. More than 45,000 putative protein-coding genes were identified. Analysis of the assembled genome revealed a whole-genome duplication event; about 8000 pairs of duplicated genes from that event survived in the Populus genome. A second, older duplication event is indistinguishably coincident with the divergence of the Populus and Arabidopsis lineages. Nucleotide substitution, tandem gene duplication, and gross chromosomal rearrangement appear to proceed substantially more slowly in Populus than in Arabidopsis. Populus has more protein-coding genes than Arabidopsis, ranging on average from 1.4 to 1.6 putative Populus homologs for each Arabidopsis gene. However, the relative frequency of protein domains in the two genomes is similar. Overrepresented exceptions in Populus include genes associated with lignocellulosic wall biosynthesis, meristem development, disease resistance, and metabolite transport.
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  • Luyssaert, S., et al. (author)
  • CO2 balance of boreal, temperate, and tropical forests derived from a global database
  • 2007
  • In: Global Change Biology. - : Wiley. - 1354-1013 .- 1365-2486. ; 13:12, s. 2509-2537
  • Research review (peer-reviewed)abstract
    • Terrestrial ecosystems sequester 2.1 Pg of atmospheric carbon annually. A large amount of the terrestrial sink is realized by forests. However, considerable uncertainties remain regarding the fate of this carbon over both short and long timescales. Relevant data to address these uncertainties are being collected at many sites around the world, but syntheses of these data are still sparse. To facilitate future synthesis activities, we have assembled a comprehensive global database for forest ecosystems, which includes carbon budget variables (fluxes and stocks), ecosystem traits (e.g. leaf area index, age), as well as ancillary site information such as management regime, climate, and soil characteristics. This publicly available database can be used to quantify global, regional or biome-specific carbon budgets; to re-examine established relationships; to test emerging hypotheses about ecosystem functioning [e.g. a constant net ecosystem production (NEP) to gross primary production (GPP) ratio]; and as benchmarks for model evaluations. In this paper, we present the first analysis of this database. We discuss the climatic influences on GPP, net primary production (NPP) and NEP and present the CO2 balances for boreal, temperate, and tropical forest biomes based on micrometeorological, ecophysiological, and biometric flux and inventory estimates. Globally, GPP of forests benefited from higher temperatures and precipitation whereas NPP saturated above either a threshold of 1500 mm precipitation or a mean annual temperature of 10 degrees C. The global pattern in NEP was insensitive to climate and is hypothesized to be mainly determined by nonclimatic conditions such as successional stage, management, site history, and site disturbance. In all biomes, closing the CO2 balance required the introduction of substantial biome-specific closure terms. Nonclosure was taken as an indication that respiratory processes, advection, and non-CO2 carbon fluxes are not presently being adequately accounted for.
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  • Moortgat-Pick, G., et al. (author)
  • Polarized positrons and electrons at the linear collider
  • 2008
  • In: Physics reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 460:4-5, s. 131-243
  • Research review (peer-reviewed)abstract
    • The proposed International Linear Collider (ILC) is well-suited for discovering physics beyond the Standard Model and for precisely unraveling the structure of the underlying physics. The physics return can be maximized by the use of polarized beams. This report shows the paramount role of polarized beams and summarizes the benefits obtained from polarizing the positron beam, as well as the electron beam. The physics case for this option is illustrated explicitly by analyzing reference reactions in different physics scenarios. The results show that positron polarization, combined with the clean experimental environment provided by the linear collider, allows to improve strongly the potential of searches for new particles and the identification of their dynamics, which opens the road to resolve shortcomings of the Standard Model. The report also presents an overview of possible designs for polarizing both beams at the ILC, as well as for measuring their polarization.
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  • Palumbo, A., et al. (author)
  • Prevention of thalidomide- and lenalidomide-associated thrombosis in myeloma
  • 2008
  • In: Leukemia. - : Springer Science and Business Media LLC. - 1476-5551 .- 0887-6924. ; 22:2, s. 414-423
  • Journal article (peer-reviewed)abstract
    • The incidence of venous thromboembolism (VTE) is more than 1%omicron annually in the general population and increases further in cancer patients. The risk of VTE is higher in multiple myeloma (MM) patients who receive thalidomide or lenalidomide, especially in combination with dexamethasone or chemotherapy. Various VTE prophylaxis strategies, such as low-molecular-Weight heparin (LMWH), warfarin or aspirin, have been investigated in small, uncontrolled clinical studies. This manuscript summarizes the available evidence and recommends a prophylaxis strategy according to a risk-assessment model. Individual risk factors for thrombosis associated with thalidomide/lenalidomide-based therapy include age, history of VTE, central venous catheter, comorbidities (infections, diabetes, cardiac disease), immobilization, surgery and inherited thrombophilia. Myeloma-related risk factors include diagnosis and hyperviscosity. VTE is very high in patients who receive high-dose dexamethasone, doxorubicin or multiagent chemotherapy in combination with thalidomide or lenalidomide, but not with bortezomib. The panel recommends aspirin for patients with <= 1 risk factor for VTE. LMWH (equivalent to enoxaparin 40 mg per day) is recommended for those with two or more individual/myeloma-related risk factors. LMWH is also recommended for all patients receiving concurrent high-dose dexamethasone or doxorubicin. Full-dose warfarin targeting a therapeutic INR of 2-3 is an alternative to LMWH, although there are limited data in the literature with this strategy. In the absence of clear data from randomized studies as a foundation for recommendations, many of the following proposed strategies are the results of common sense or derive from the extrapolation of data from many studies not specifically designed to answer these questions. Further investigation is needed to define the best VTE prophylaxis.
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  • Alwall, J., et al. (author)
  • A standard format for Les Houches Event Files
  • 2007
  • In: Computer Physics Communications. - : Elsevier BV. - 0010-4655. ; 176:4, s. 300-304
  • Journal article (peer-reviewed)abstract
    • A standard file format is proposed to store process and event information, primarily output from partoti-level event generators for further use by general-purpose ones. The information content is identical with what was already defined by the Les Houches Accord five years ago, but then in terms of Fortran commonblocks. This information is embedded in a minimal XML-style structure, for clarity and to simplify parsing.
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18.
  • Arbaugh, J.B, et al. (author)
  • Developing a community of inquiry instrument : testing a measure of the Community of Inquiry framework using a multi-institutional sample
  • 2009
  • In: The Internet and higher education. - : Elsevier BV. - 1096-7516 .- 1873-5525. ; 11:3-4, s. 133-136
  • Journal article (peer-reviewed)abstract
    • This article reports on the multi-institutional development and validation of an instrument that attempts to operationalize Garrison, Anderson and Archer's Community of Inquiry (Col) framework (2000). The results of the study suggest that the instrument is a valid, reliable, and efficient measure of the dimensions of social presence and cognitive presence, thereby providing additional support for the validity of the Col as a framework for constructing effective online learning environments. While factor analysis supported the idea of teaching presence as a construct, it also suggested that the construct consisted of two factors-one related to course design and organization and the other related to instructor behavior during the course. The article concludes with a discussion of potential implications of further refinement of the Col measures for researchers, designers, administrators, and instructors.
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19.
  • Belavy, D. L., et al. (author)
  • Analysis of phasic and tonic electromyographic signal characteristics: Electromyographic synthesis and comparison of novel morphological and linear-envelope approaches
  • 2009
  • In: Journal of Electromyography and Kinesiology. - 1873-5711 .- 1050-6411. ; 19:1, s. 10-21
  • Journal article (peer-reviewed)abstract
    • The pattern of tonic and phasic components in an EMG signal reflects the underlying behaviour of the central nervous system (CNS) in controlling the musculature. One avenue for gaining a better understanding of this behaviour is to seek a quantitative characterisation of these phasic and tonic components. We propose that these signal characteristics call range between unvarying, tonic and intermittent, phasic activation through a continuum of EMG amplitude modulation. In this paper, we present two new algorithms for quantifying amplitude modulation: a linear-envelope approach, and a mathematical morphology approach. In addition we present all algorithm for synthesising EMG signals with known amplitude modulation. The efficacy of the synthesis algorithm is demonstrated using real EMG data. We present an evaluation and comparison of the two algorithms for quantifying amplitude modulation based on synthetic data generated by the proposed synthesis algorithm. The results demonstrate that the EMG synthesis parameters represent 91.9% and 96.2% of the variance of linear-envelopes extracted from lumbo-pelvic muscle EMG signals collected from subjects performing a repetitive-movement task. This depended, however, on the muscle and movement-speed considered (F = 4.02, p
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  • Dispenzieri, A., et al. (author)
  • International Myeloma Working Group guidelines for serum-free light chain analysis in multiple myeloma and related disorders
  • 2009
  • In: Leukemia. - : Springer Science and Business Media LLC. - 1476-5551 .- 0887-6924. ; 23:2, s. 215-224
  • Research review (peer-reviewed)abstract
    • The serum immunoglobulin-free light chain (FLC) assay measures levels of free kappa and lambda immunoglobulin light chains. There are three major indications for the FLC assay in the evaluation and management of multiple myeloma and related plasma cell disorders (PCD). In the context of screening, the serum FLC assay in combination with serum protein electrophoresis (PEL) and immunofixation yields high sensitivity, and negates the need for 24-h urine studies for diagnoses other than light chain amyloidosis (AL). Second, the baseline FLC measurement is of major prognostic value in virtually every PCD. Third, the FLC assay allows for quantitative monitoring of patients with oligosecretory PCD, including AL, oligosecretory myeloma and nearly two-thirds of patients who had previously been deemed to have non-secretory myeloma. In AL patients, serial FLC measurements outperform PEL and immunofixation. In oligosecretory myeloma patients, although not formally validated, serial FLC measurements reduce the need for frequent bone marrow biopsies. In contrast, there are no data to support using FLC assay in place of 24-h urine PEL for monitoring or for serial measurements in PCD with measurable disease by serum or urine PEL. This paper provides consensus guidelines for the use of this important assay, in the diagnosis and management of clonal PCD.
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  • Fricke, W, et al. (author)
  • The short-term growth response to salt of the developing barley leaf
  • 2006
  • In: Journal of Experimental Botany. - : Oxford University Press (OUP). - 0022-0957 .- 1460-2431. ; 57:5, s. 1079-1095
  • Journal article (peer-reviewed)abstract
    • Recent results concerning the short-term growth response to salinity of the developing barley leaf are reviewed. Plants were grown hydroponically and the growth response of leaf 3 was studied between 10 min and 5 d following addition of 100 mM NaCl to the root medium. The aim of the experiments was to relate changes in variables that are likely to affect cell elongation to changes in leaf growth. Changes in hormone content (ABA, cytokinins), water and solute relationships (osmolality, turgor, water potential, solute concentrations), gene expression (water channel), cuticle deposition, membrane potential, and transpiration were followed, while leaf elongation velocity was monitored. Leaf elongation decreased close to zero within seconds following addition of NaCl. Between 20 and 30 min after exposure to salt, elongation velocity recovered rather abruptly, to about 46% of the pre-stress level, and remained at the reduced rate for the following 5 d, when it reached about 70% of the level in non-stressed plants. Biophysical and physiological analyses led to three major conclusions. (i) The immediate reduction and sudden recovery in elongation velocity is due to changes in the water potential gradient between leaf xylem and peripheral elongating cells. Changes in transpiration, ABA and cytokinin content, water channel expression, and plasma membrane potential are involved in this response. (ii) Significant solute accumulation, which aids growth recovery, is detectable from 1 h onwards; growing and non-growing leaf regions and mesophyll and epidermis differ in their solute response. (iii) Cuticular wax density is not affected by short-term exposure to salt; transpirational changes are due to stomatal control.
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  • Giralt, S., et al. (author)
  • International myeloma working group (IMWG) consensus statement and guidelines regarding the current status of stem cell collection and high-dose therapy for multiple myeloma and the role of plerixafor (AMD 3100)
  • 2009
  • In: Leukemia. - : Springer Science and Business Media LLC. - 1476-5551 .- 0887-6924. ; 23:10, s. 1904-1912
  • Journal article (peer-reviewed)abstract
    • Multiple myeloma is the most common indication for high-dose chemotherapy with autologous stem cell support (ASCT) in North America today. Stem cell procurement for ASCT has most commonly been performed with stem cell mobilization using colony-stimulating factors with or without prior chemotherapy. The target CD34+ cell dose to be collected as well as the number of apheresis performed varies throughout the country, but a minimum of 2 million CD34+ cells/kg has been traditionally used for the support of one cycle of high-dose therapy. With the advent of plerixafor (AMD3100) (a novel stem cell mobilization agent), it is pertinent to review the current status of stem cell mobilization for myeloma as well as the role of autologous stem cell transplantation in this disease. On June 1, 2008, a panel of experts was convened by the International Myeloma Foundation to address issues regarding stem cell mobilization and autologous transplantation in myeloma in the context of new therapies. The panel was asked to discuss a variety of issues regarding stem cell collection and transplantation in myeloma especially with the arrival of plerixafor. Herein, is a summary of their deliberations and conclusions. Leukemia (2009) 23, 1904-1912; doi: 10.1038/leu.2009.127; published online 25 June 2009
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  • Jörgensen, Tove, et al. (author)
  • Comparative analyses of population structure in two subspecies of Nigella degenii: Evidence for diversifying selection on pollen-color dimorphisms
  • 2006
  • In: Evolution. - 1558-5646. ; 60:3, s. 518-528
  • Journal article (peer-reviewed)abstract
    • Flower color can be a major determinant of plant fitness, not only because of preferential visitation by pollinators but also because of pleiotropic relationships between the expression of floral pigments and biochemically related compounds that influence vegetative performance variables. Different environments may therefore favor different pigmentation phenotypes. We examined whether spatially varying selection has played a major role in shaping large-scale patterns of differentiation in two subspecies of Nigella degenii (Ranunculaceae), with particular emphasis on pollen color. The two subspecies appear to have been genetically isolated for substantial periods of time and, therefore, provide a "replicated test" for the effect of natural selection. Estimates of population structure based on a suite of floral and vegetative characters were compared with the corresponding data for amplified fragment length polymorphism (AFLP) markers, which were assumed to be selectively neutral. We found low levels of genetic structure within the subspecies using both the AFLP markers (F-ST <= 0.05) and quantitative characters (Q(ST) <= 0.15), with no statistically significant differences between the two measures. There is, therefore, no evidence of diversifying selection being important in structuring variation in quantitative characters within each of the two subspecies. In contrast, estimates of differentiation in pollen color (F-ST <= 0.10) significantly exceeded the neutral expectations (estimated from AFLP data), Suggesting that local adaptation has played a key role in the evolution of this monogenic character.
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  • Mangano, Valentina D, et al. (author)
  • Lack of association of Interferon Regulatory Factor 1 with severe malaria in affected child‐parental trio studies across three African populations
  • 2009
  • In: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 4:1, s. e4206-
  • Journal article (peer-reviewed)abstract
    • Interferon Regulatory Factor 1 (IRF-1) is a member of the IRF family of transcription factors, which have key and diverse roles in the gene-regulatory networks of the immune system. IRF-1 has been described as a critical mediator of IFN-gamma signalling and as the major player in driving TH1 type responses. It is therefore likely to be crucial in both innate and adaptive responses against intracellular pathogens such as Plasmodium falciparum. Polymorphisms at the human IRF1 locus have been previously found to be associated with the ability to control P. falciparum infection in populations naturally exposed to malaria. In order to test whether genetic variation at the IRF1 locus also affects the risk of developing severe malaria, we performed a family-based test of association for 18 Single Nucleotide Polymorphisms (SNPs) across the gene in three African populations, using genotype data from 961 trios consisting of one affected child and his/her two parents (555 from The Gambia, 204 from Kenya and 202 from Malawi). No significant association with severe malaria or severe malaria subphenotypes (cerebral malaria and severe malaria anaemia) was observed for any of the SNPs/haplotypes tested in any of the study populations. Our results offer no evidence that the molecular pathways regulated by the transcription factor IRF-1 are involved in the immune-based pathogenesis of severe malaria.
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  • Palumbo, A., et al. (author)
  • International Myeloma Working Group guidelines for the management of multiple myeloma patients ineligible for standard high-dose chemotherapy with autologous stem cell transplantation
  • 2009
  • In: Leukemia. - : Springer Science and Business Media LLC. - 1476-5551 .- 0887-6924. ; 23:10, s. 1716-1730
  • Research review (peer-reviewed)abstract
    • In 2005, the first guidelines were published on the management of patients with multiple myeloma (MM). An expert panel reviewed the currently available literature as the basis for a set of revised and updated consensus guidelines for the diagnosis and management of patients with MM who are not eligible for autologous stem cell transplantation. Here we present recommendations on the diagnosis, treatment of newly diagnosed non-transplant-eligible patients and the management of complications occurring during induction therapy among these patients. These guidelines will aid the physician in daily clinical practice and will ensure optimal care for patients with MM. Leukemia (2009) 23, 1716-1730; doi: 10.1038/leu.2009.122; published online 4 June 2009
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  • Piao, Shilong, et al. (author)
  • Net carbon dioxide losses of northern ecosystems in response to autumn warming
  • 2008
  • In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 451:7174, s. 3-49
  • Journal article (peer-reviewed)abstract
    • The carbon balance of terrestrial ecosystems is particularly sensitive to climatic changes in autumn and spring(1-4), with spring and autumn temperatures over northern latitudes having risen by about 1.1 degrees C and 0.8 degrees C, respectively, over the past two decades(5). A simultaneous greening trend has also been observed, characterized by a longer growing season and greater photosynthetic activity(6,7). These observations have led to speculation that spring and autumn warming could enhance carbon sequestration and extend the period of net carbon uptake in the future(8). Here we analyse interannual variations in atmospheric carbon dioxide concentration data and ecosystem carbon dioxide fluxes. We find that atmospheric records from the past 20 years show a trend towards an earlier autumn- to- winter carbon dioxide build- up, suggesting a shorter net carbon uptake period. This trend cannot be explained by changes in atmospheric transport alone and, together with the ecosystem flux data, suggest increasing carbon losses in autumn. We use a process- based terrestrial biosphere model and satellite vegetation greenness index observations to investigate further the observed seasonal response of northern ecosystems to autumnal warming. We find that both photosynthesis and respiration increase during autumn warming, but the increase in respiration is greater. In contrast, warming increases photosynthesis more than respiration in spring. Our simulations and observations indicate that northern terrestrial ecosystems may currently lose carbon dioxide in response to autumn warming, with a sensitivity of about 0.2 PgC degrees C-1, offsetting 90% of the increased carbon dioxide uptake during spring. If future autumn warming occurs at a faster rate than in spring, the ability of northern ecosystems to sequester carbon may be diminished earlier than previously suggested(9,10).
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  • Roelens, M. A. F., et al. (author)
  • Linear frequency resolved optical gating as a line monitoring tool
  • 2006
  • In: 2006 Optical Fiber Communication Conference, and the 2006 National Fiber Optic Engineers Conference. - : IEEE Computer Society. - 1557528039 - 9781557528032
  • Conference paper (peer-reviewed)abstract
    • We demonstrate the use of spectrograms for pulse monitoring. The technique can characterize the phase and intensity of data modulated pulses after transmission over a fiber span including a tunable dispersion compensating grating. © 2006 Optical Society of America.
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  • Swan, Karen, et al. (author)
  • Researching online communities of inquiry : New CoI  survey instrument.
  • 2008
  • In: Proceedings of World Conference on Educational Multimedia, Hypermedia and Telecommunications 2008. ; , s. 5812-5820
  • Conference paper (peer-reviewed)abstract
    • The Community of Inquiry (CoI) framework developed by Garrison, Anderson and Archer (2000) provides a theoretical model of online learning processes that has been used by many scholars in the field of online education. However, research utilizing the CoI framework needs to move from investigating single components of the model to integrating all three components and from situated studies using unique measures to inter-institutional research using common measures. In this paper, we summarize the CoI model and research to date on its multiple components, and report on validation of a CoI survey instrument designed to support common, integrated Community of Inquiry research across institutions.
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  • Swan, K., et al. (author)
  • Validating a measurement tool of presence in online communities of inquiry
  • 2008
  • In: E-mentor. - 1731-6758 .- 1731-7428. ; 2:24
  • Journal article (peer-reviewed)abstract
    • This article examines work related to the development and validation of a measurement tool for the Communityof Inquiry (CoI) framework in online settings. The framework consists of three elements: social presence,teaching presence and cognitive presence, each of which is integral to the instrument. The 34 item instrument,and thus framework, was tested after being administered at four institutions in the Summer of 2007. The articlealso includes a discussion of implications for the future use of the CoI survey and the CoI framework itself.
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  • Waltzman, Rand, et al. (author)
  • In the requirements lies the power
  • 2007
  • In: 19th International Conference on Software Engineering and Knowledge Engineering, SEKE 2007. - 9781627486613 ; , s. 185-190
  • Conference paper (peer-reviewed)abstract
    • System requirements expressed as scenarios represent a rich source of knowledge about a system and the context in which it is used. This is because the scenarios are the result of extensive collaborative efforts of a wide variety of stakeholders and are in a form to which all can relate. Ideally, they serve to represent the interests of all stakeholders at each stage of the development life cycle. Our focus in this paper is system testing against requirements. In particular, we show (1) how the knowledge represented in scenarios (using ScenarioML) can be directly transformed into an operational knowledge base in a rule-based programming language (JESS), (2) how this knowledge base can be used in system testing to compute, manage, and compare expectations of system behavior to actual system behavior relative to the requirements, and (3) how this can be achieved in a manner that is transparent to all stakeholders. The power of this approach derives from the peculiarly reflective character of knowledge based systems and their explicit use of meta-information and meta-information processing. We demonstrate the viability of our approach by its application to the AquaLush system in which we detected several violations of the system's stated requirements.
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36.
  • Worley, K., et al. (author)
  • Single locus typing of MHC class I and class II B loci in a population of red jungle fowl
  • 2008
  • In: Immunogenetics. - : Springer Science and Business Media LLC. - 0093-7711 .- 1432-1211. ; 60:5, s. 233-247
  • Journal article (peer-reviewed)abstract
    • In species with duplicated major histocompatibility complex (MHC) genes, estimates of genetic variation often rely on multilocus measures of diversity. It is possible that such measures might not always detect more detailed patterns of selection at individual loci. Here, we describe a method that allows us to investigate classical MHC diversity in red jungle fowl (Gallus gallus), the wild ancestor of the domestic chicken, using a single locus approach. This is possible due to the well-characterised gene organisation of the 'minimal essential' MHC (BF/BL region) of the domestic chicken, which comprises two differentially expressed duplicated class I (BF) and two class II B (BLB) genes. Using a combination of reference strand-mediated conformation analysis, cloning and sequencing, we identify nine BF and ten BLB alleles in a captive population of jungle fowl. We show that six BF and five BLB alleles are from the more highly expressed locus of each gene, BF2 and BLB2, respectively. An excess of non-synonymous substitutions across the jungle fowl BF/BL region suggests that diversifying selection has acted on this population. Importantly, single locus screening reveals that the strength of selection is greatest on the highly expressed BF2 locus. This is the first time that a population of red jungle fowl has been typed at the MHC region, laying the basis for further research into the underlying processes acting to maintain MHC diversity in this and other species. © 2008 Springer-Verlag.
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