Non-Fourier conduction models remedy the paradox of infinite signal speed in the traditional parabolic heat equation. For applications involving very short length or time scales, hyperbolic ...conduction models better represent the physical thermal transport processes. This paper reviews the Maxwell–Cattaneo–Vernotte modification of the Fourier conduction law and describes its implementation within a spacetime discontinuous Galerkin (SDG) finite element method that admits jumps in the primary variables across element boundaries with arbitrary orientation in space and time. A causal, advancing-front meshing procedure enables a patch-wise solution procedure with linear complexity in the number of spacetime elements. An
h-adaptive scheme and a special SDG shock-capturing operator accurately resolve sharp solution features in both space and time. Numerical results for one spatial dimension demonstrate the convergence properties of the SDG method as well as the effectiveness of the shock-capturing method. Simulations in two spatial dimensions demonstrate the proposed method’s ability to accurately resolve continuous and discontinuous thermal waves in problems where rapid and localized heating of the conducting medium takes place.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Research shows charter schools are more segregated by race and class than are traditional public schools. I investigate an underexamined mechanism for this segregation: Charter schools project ...identities corresponding to parents’ race- and class-specific parenting styles and educational values. I use computational text analysis to detect the emphasis on inquiry-based learning in the websites of all charter schools operating in 2015–16. I then estimate mixed linear regression models to test the relationships between ideological emphasis and school- and district-level poverty and ethnicity. I thereby transcend methodological problems in scholarship on charter school identities by collecting contemporary, populationwide data and by blending text analysis with hypothesis testing. Findings suggest charter school identities are both race and class specific, outlining a new mechanism by which school choice may consolidate parents by race and class—and paving the way for behavioral and longitudinal studies. This project contributes to literatures on school choice and educational stratification.
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BFBNIB, INZLJ, NMLJ, NUK, OILJ, PNG, SAZU, UKNU, UL, UM, UPUK, ZRSKP
We present a dimensional analysis and self-similar solutions for linear elastodynamics with extensions to dynamic fracture models based on cohesive traction–separation relations. We formulate the ...problem using differential forms in spacetime and show that the scaling rules expressed in terms of forms are simpler and more uniform than those obtained for tensor representations of the solution. In the extension to cohesive elastodynamic fracture, we identify and study the influence of certain intrinsic cohesive scales on dynamic fracture behavior and describe a fundamental set of nondimensional groups that uniquely identifies families of self-similar solutions. We present numerical studies of the influence of selected nondimensional parameters on dynamic fracture response to verify the dimensional analysis, including the identification of the fundamental set for cohesive fracture mechanics. We show that distinct values of a widely-used nondimensional quantity can produce self-similar solutions. Therefore, this quantity is not fundamental, and it cannot parameterize dynamic, cohesive-fracture response.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This paper presents the new algorithm of PP-PFC (Pole-placement Predictive Functional Control) for stable, linear under-damped higher-order processes. It is shown that while conventional PFC aims to ...get first-order exponential behavior, this is not always straightforward with significant under-damped modes and hence a pole-placement PFC algorithm is proposed which can be tuned more precisely to achieve the desired dynamics, but exploits complex number algebra and linear combinations in order to deliver guarantees of stability and performance. Nevertheless, practical implementation is easier by avoiding complex number algebra and hence a modified formulation of the PP-PFC algorithm is also presented which utilises just real numbers while retaining the key attributes of simple algebra, coding and tuning. The potential advantages are demonstrated with numerical examples and real-time control of a laboratory plant.
•Pole-placement Predictive Functional Control is introduced for under-damped plants.•The tuning of PP-PFC is more straightforward than with a conventional PFC.•PP-PFC allows the selection of target closed-loop poles.•The paper demonstrates how to avoid the use of complex algebra.•The PP-PFC algorithm is demonstrated on a servo rig with a flexible joint.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Fabry disease Stephan, F; Haber, R
Annales de dermatologie et de vénéréologie
144, Issue:
2
Journal Article
Peer reviewed
Fabry disease, also known as Anderson-Fabry disease or angiokeratoma corporis diffusum universale, is an X-linked recessive form of sphingolipidosis caused by total or partial deficiency of the ...lysosomal hydrolase, alpha-galactosidase A. From the youngest age, it results in a gradual ubiquitous build-up of glycosphingolipids that are not degraded by the missing enzyme. Cutaneous, neurological, nephrologic, cardiac, gastrointestinal, ophthalmological, respiratory, cochleovestibular and haematological involvement are responsible for increased mortality and significant impairment of quality of life in subjects affected by the disease. Angiokeratomas are the most common cutaneous sign of this disease, although they are not specific to it and must be distinguished from angiokeratomas either occurring in isolation or associated with systemic diseases. Other cutaneous signs encountered in this disease include hyperhidrosis, oral lesions, lower limb oedemas, etc. The diagnosis is mainly clinical and should be considered in the presence of a personal and/or familial history; it is confirmed by assay of enzyme activity within leucocytes or by molecular studies. Management is multidisciplinary and involves symptomatic treatment as well as specific treatment, resulting in improved survival and enhanced quality of life for patients presenting the disease. Enzyme replacement therapy with alpha-galactosidase A forms the cornerstone of specific treatment and may be associated with other types of treatments such as galactose and molecular chaperones. Gene therapy is now also used extensively. At present, these marked therapeutic advances, which closely involve dermatologists, could help transform the prognosis for patients presenting Fabry disease.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
This paper gives new insight and design proposals for Predictive Functional Control (PFC) algorithms. Common practice and indeed a requirement of PFC is to select a coincidence horizon greater than ...one for high-order systems and for the link between the design parameters and the desired dynamic to be weak. Here the proposal is to use parallel first-order models to form an independent prediction model and show that with these it is possible both to use a coincidence horizon of one and moreover to obtain precisely the desired closed-loop dynamics. It is shown through analysis that the use of a coincidence horizon of one greatly simplifies coding, tuning, constraint handling and implementation. The paper derives the key results for high-order and non-minimum phase processes and also demonstrates the flexibility and potential industrial utility of the proposal.
•Extending the ease and efficacy of tuning for PFC to higher order processes.•Computationally efficient and easy to code predictive control algorithms.•Analysis and insights into the PFC approach to control design.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Malignant cells exhibit increased glycolytic metabolism, and in many cases increased glucose transporter gene expression. The authors hypothesized that GLUT1 glucose transporter expression is ...increased in colorectal carcinoma, and that the degree of expression might have prognostic significance.
GLUT1 glucose transporter immunostaining was studied in normal colon and benign colon adenomas and in 112 colorectal carcinomas from patients for whom long term clinical outcome was known.
GLUT1 immunostaining was absent in normal colorectal epithelium and tubular adenomas, and absent or only weakly apparent in tubulovillous adenomas. The majority of carcinomas (101 of 112; 90%) had GLUT1 immunostaining. Tumors from 92 patients had low GLUT1 expression (< 50% of cells were GLUT1 positive) and 19 of these patients (21%) died of disease during follow-up. In contrast, tumors from 20 patients had high GLUT1 expression (> 50% of cells were GLUT1 positive) and 9 of these patients (45%) died of disease during follow-up. Disease specific mortality was greater in patients with high GLUT1 tumors (relative risk of 2.4; P=0.02). In a multivariate analysis to assess whether high GLUT1 staining correlated with increased mortality independently of Dukes stage, the risk of death from colon carcinoma in the group with high GLUT1 staining was 2.3 times that in the group with low GLUT1 staining, a difference that approached statistical significance (P=0.07).
GLUT1 glucose transporter expression is associated strongly with neoplastic progression in the colon, and assessment of the extent of GLUT1 immunostaining in colorectal carcinoma identifies patients with a poorer prognosis.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
19.
A geometry projection method for shape optimization Norato, J.; Haber, R.; Tortorelli, D. ...
International journal for numerical methods in engineering,
14 August 2004, Volume:
60, Issue:
14
Journal Article