6,559 research outputs found
The classification and management of limestone pavements - an endangered habitat
This thesis describes an in-depth study of limestone pavements across North West England and North Wales. The aim was to combine elements of geodiversity and biodiversity in order to create a holistic limestone pavement classification to inform future management. A field-based research protocol was used to assess a stratified random sample (46 pavements), accounting for approximately 10% of the limestone pavements in the geographical area. Detailed analyses of key elements are presented, along with important issues that continue to pose threats to this Annex One Priority Habitat. This research resulted in a comprehensive classification, using TWINSPAN analysis and Nonmetric Multidimensional Scaling, identifying six distinct holistic functional groups. The prime factors driving limestone pavement morphology, and hence the classification, were established to be lithology, proximity to structural fault, altitude and human intervention, particularly in terms of grazing intensity. Three upland, open limestone pavement classes were formed. Of these, the richest in terms of geodiversity and biodiversity was the group with the thickest bedding planes and hence the deepest grikes, typically greater than 1m. The class that was most species-poor was "at the highest altitude (above 450m), formed on the thin limestones of the Yoredales. These were characterised by shallow, wide grikes. The third upland limestone pavement group had mid-range grikes, generally 0.5-1m in depth, and small clints. Two wooded classes were identified. One was a lowland 'classic' wooded limestone pavement group with deep, narrow grikes and shallow soils. Indicator species included Juniperus communis and Taxus baccata. The second wooded group was situated proximal to a major structural fault. In this group the pavement dip ranged between 10°-40° with well-runnelled clints that were heavily moss-covered. The sixth group was low altitude, proximal to the coast, characterised by low moss growth, un-vegetated clints and the presence of Ulex europaeus. Conservation management was identified as key to the quality of the limestone pavement habitat and this thesis identifies best management practises and links these to the holistic limestone pavement classification. Finally, as a sample case study, this thesis presents mollusc species and diversity from eleven of the Yorkshire limestone pavements. Analysis establishes significant links between geodiversity and mollusc populations, with key drivers for mollusc communities echoing those of plant species on limestone pavement.Funded by the Yorkshire Dales National Park and the University of Chester
Finite disturbance effect on the stability of a laminar incompressible wake behind a flat plate
An integral method is used to investigate the interaction between a two-dimensional, single frequency finite amplitude disturbance in a laminar, incompressible wake behind a flat plate at zero incidence. The mean flow is assumed to be a non-parallel flow characterized by a few shape parameters. Distribution of the fluctuation across the wake is obtained as functions of those mean flow parameters by solving the inviscid Rayleigh equation using the local mean flow. The variations of the fluctuation amplitude and of the shape parameters for the mean flow are then obtained by solving a set of ordinary differential equations derived from the momentum and energy integral equations. The interaction between the mean flow and the fluctuation through Reynolds stresses plays an important role in the present formulation, and the theoretical results show good agreement with the measurements of Sato & Kuriki (1961)
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Measuring mathematical resilience : an application of the construct of resilience to the study of mathematics
To meet the challenge of accelerating demands for quantitative literacy in the work force,
improvements are needed in mathematics education. Student skill must be increased at all ability
levels while also reducing the achievement gap across gender, racial and ethnic groups to
increase their participation in advanced mathematics coursework and representation in
mathematics related careers (National Mathematics Advisory Panel, 2008). Research has shown
that affective traits such as motivation and attitude are linked to increased likelihood of taking
advanced mathematics courses (Ma, 2006) and are significant predictors of improved cognitive
activity and achievement (Buff, Reusser, Rakoczy,& Pauli, 2011; Ethington & Wolfe, 1986). In
addition, males generally score more favorably than females on affective variables related to
mathematics achievement and persistence (McGraw, Lubienski, & Strutchens, 2006; Sherman &
Fennema, 1977; Wilkins and Ma, 2003). Although psychological resilience has been researched
extensively (Luthar, Cicchetti, & Becker, 2000; Luthar, 2007) the study of mathematical
resilience, defined as a positive adaptive stance to mathematics which allows students to
continue learning despite adversity, represents a new approach (Johnston-Wilder & Lee, 2010;
Rivera & Waxman, 2011). Math anxiety looks at maladaptive response to learning mathematics
and is well-studied (Hembree, 1990; Richardson & Suinn, 1977; Tobias, 1978). In contrast,
resilience incorporates factors associated with optimal functioning. Although mathematical
resilience has been identified as important for success (Johnston-Wilder & Lee, 2010; Rivera &
Waxman, 2011), little consensus exists around its definition and no measures of resilience have
been rigorously developed and/or validated. Rivera & Waxman (2011) identified the use of
teacher nomination of resilient students as a limitation of their study, further motivating
development of an instrument. This presentation will report on efforts to develop and validate an
instrument measuring mathematical resilience. Ultimately, the measure will aid in developing
and testing models that gauge the role of mathematical resilience in student achievement and
persistence in advanced coursework. These models can be used to develop interventions to
improve mathematical resilience, achievement, and quantitative literacy (Johnston-Wilder &
Lee, 2010)
Screening for HLA-B*1502 Polymorphism in Febrile Seizure Predicted Lead to Epilepsy
Mutation in neuronal sodium channel -1-subunit gene (SCN1A) and neuronal sodium channel -1-subunit gene (SCN1B) has been linked with forms of generalized epilepsy with febrile seizure plus (GEFS+) and epileptic infantile syndrome like severe myoclonic epilepsy of infancy (SMEI) (Mulley et al., 2005; Scheffer et al., 2007). Since this idiopathic epilepsy typically begins with prolonged febrile seizures (FS) in the first year of life, therefore febrile seizure patient with mutation in SCN1A has a high risk to develop epilepsy on their later life (Dube et al., 2009). Carbamazepine (CBZ) has been known as the most common anti-epileptic drug which can cause Steven-Johnson Syndrome (SJS) and toxic epidermal necrolysis (TEN) in patients with HLA-B*1502 polymorphism. Since the Javanese population have 16,67% of these allele, studying the presence of these allele in patients predicted epilepsy is important.
Furthermore, this study was intended to develop a PCR-based diagnostic protocol to screen HLA-B*1502 polymorphism in epileptic patients to prevent SJS/TEN by carbamazepine. Focusing on epileptic predicted patients, HLA-B*1502 genotyping by sequence specific primer (SSP)-PCR was performed on 31 repeated FS patients with mutation in SCN1A and SCN1A/SCN1B gene.
The result show that the HLA-B*1502 polymorphism was detected in 14 (45,2%) individuals including 8 cases related to mutation SCN1A gene and 6 to SCN1A/SCN1B gene. It illustrates that HLA-B*1502 allele is frequent in these patients. It can thus be suggested that detection of this allele should be done before epilepsy treatment. Later, patients with this allele should avoid CBZ to prevent SJS/TEN during drug administration
Electronic Commerce within Organizations: Lessons From Two Cases
This paper describes research concerning two companies that have been seeking to improve collaboration and communication internally across functional and departmental boundaries through the introduction of intranets. In one case, the development and introduction of the system lead to unintended, negative effects; in the other, there is preliminary evidence to suggest that the results have been much more positive. The experiences of the two companies help to reinforce lessons that have been known for some time – in relation, for example, to socio-technical systems and Information Systems (IS) failures (e.g. Bostrom & Heinen, 1977a,b). The fact that these two cases are contemporary and that there appears to be evidence that some of the lessons of the past have been forgotten or have remained unheard, suggests nonetheless that the comparison may be enlightening
More than a Footnote: The Perils of Multidisciplinary Research Collaboration
This paper considers the espoused reasons for the recent emphasis on multidisciplinary research, drawing on some of the literature on multi-functional networking and teamworking in industry. We critique the predominately prescriptive and overly simplistic accounts of multidisciplinary working in academia. Finally, we distinguish between interdisciplinary and multidisciplinary research and consider the implications of our analysis in terms of encouraging the former, particularly in the Information Systems domain
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