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1. Sickle Cell Trait and Kidney Disease in People of African Ancestry With HIV

Author

Rachel K.Y. Hung, Elizabeth Binns-Roemer, John W. Booth, Rachel Hilton, Julie Fox, Fiona Burns, Mark Harber, Andrew Ustianowski, Lisa Hamzah, James E. Burns, Amanda Clarke, David A. Price, Stephen Kegg, Denis Onyango, Beatriz Santana-Suarez, Lucy Campbell, Kate Bramham, Claire C. Sharpe, Caroline A. Sabin, Cheryl A. Winkler, Frank A. Post, John Booth, Anele Waters, James Hand, Chris Clarke, Sarah Murphy, Maurice Murphy, Marion Campbell, Celia Richardson, Alyson Knott, Gemma Weir, Rebecca Cleig, Helena Soviarova, Lisa Barbour, Tanya Adams, Vicky Kennard, Vittorio Trevitt, Rachael Jones, Jeremy Levy, Alexandra Schoolmeester, Serah Duro, May Rabuya, Deborah Jordan, Teresa Solano, Hiromi Uzu, Karen Williams, Julianne Lwanga, Linda Ekaette Reid-Amoruso, Hannah Gamlen, Robert J. Stocker, Fiona Ryan, Karina Mahiouz, Tess Cheetham, Claire Williams, Achyuta Nori, Caroline Thomas, Sivaraj Venkateshwaran, Jessica Doctor, Andrea Berlanga, Frank Post, Leigh McQueen, Priya Bhagwandin, Bee Barbini, Emily Wandolo, Tim Appleby, Lois Driver, Sophy Parr, Hongbo Deng, Julie Barber, Andrew Crowe, Chris Taylor, Mary Poulton, Vida Boateng, Marie-Pierre Klein, Caitlin O’Brien, Samuel Ohene-Adomako, Christian Buckingham, Daniel Trotman, Killian Quinn, Kate Flanagan, Verity Sullivan, Holly Middleditch, Itty Samuel, Elizabeth Hamlyn, Candice McDonald, Ana Canoso, Emeka Agbasi, Maria Liskova, Sarah Barber, Amanda Samarawickrama, Zoe Ottaway, Claire Norcross, Amelia Oliveira, Jane Minton, Gary Lamont, Ruby Cross, Gaushiya Saiyad, Shadia Ahmed, Rebecca Ashworth, Nicola Window, J. Murira, Khine Phyu, Gabriella Lindergard, Jonathan Shaw, Sarah Holland, Claire Fox, Jan Flaherty, Margaret-Anne Bevan, Valerie George, David Chadwick, Marie Branch, Pauline Lambert, Adele Craggs, Sarah Pett, Hinal Lukha, Nina Vora, Marzia Fiorino, Maria Muller Nunez, Deirdre Sally, Erica Pool, Rebecca Matthews, David Ashley Price, Tara Stothard, Bijal Patel, Ian McVittie, Ciara Kennedy, Uli Shwab, Brendan Payne, Sarah Duncan, Jill Dixon, Mathias Schmid, Adam Evans, Christopher Duncan, Ewan Hunter, Yusri Taha, Natasha Astill, Cheryl Winkler, Victor David, Jonathan Ainsworth, Rachel Vincent, Chloe Saad, Sarah Skinner, Hocine Azzoug, Judith Russell, Tarik Moussaoui, Emily Mabonga, Donna Ward, J. Francoise, W. Larbi, Sue Mitchell, A. Manning, V. Russell, Nnenna Ngwu, Jonathan Edwards, Nargis Hemat, Tom Fernandez, Filippo Ferro, Jorge Ferreira, Alice Nightingale, Tasha Oakes-Monger, Darwin Matila, Pedro Nogueira, Victoria Mutagwanya, Catherine Cosgrove, Catherine Emily Isitt, Helen Webb, Joyce Popoola, Kate Korley, Mark Mencias, Patricia Ribeiro, Rajeshwar Ramkhelawn, Sandra Oliva Lara, Sara Sajijad, Alan Winston, Amber Shaw, Claire Petersen, Kyle Ring, Melanie Rosenvinge, Thembi Moyo, Faith Odong, Katherine Gantert, Tina Ibe, Caroline Sabin, and Teresa Hill

Subjects
Africa, APOL1, HIV, kidney, SCT, sickle cell trait, Diseases of the genitourinary system. Urology, RC870-923
Abstract

Introduction: Sickle cell trait (SCT) has been associated with chronic kidney disease (CKD) in African Americans, although evidence for its impact in Africans and people with HIV is currently lacking. We conducted a cross-sectional study investigating the association between SCT and kidney disease in people of African ancestry with HIV in the UK. Methods: The primary outcome was estimated glomerular filtration rate (eGFR) 50 mg/mmol), and albuminuria (albumin-to-creatinine ratio >3 mg/mmol). Multivariable logistic regression was used to estimate the associations between SCT and kidney disease outcomes. Results: A total of 2895 participants (mean age 48.1 [SD 10.3], 57.2% female) were included, of whom 335 (11.6%) had SCT and 352 (12.2%) had eGFR

Published
2022
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2. GSTM1 Copy Number and Kidney Disease in People With HIV

Author

Rachel K.Y. Hung, Kerry-Lee Rosenberg, Victor David, Elizabeth Binns-Roemer, John W. Booth, Rachel Hilton, Julie Fox, Fiona Burns, Andrew Ustianowski, Catherine Cosgrove, Lisa Hamzah, James E. Burns, Amanda Clarke, David Chadwick, David A. Price, Stephen Kegg, Lucy Campbell, Kate Bramham, Caroline A. Sabin, Frank A. Post, Cheryl A. Winkler, Anele Waters, James Hand, Chris Clarke, Sarah Murphy, Maurice Murphy, Marion Campbell, Celia Richardson, Alyson Knott, Gemma Weir, Rebecca Cleig, Helena Soviarova, Lisa Barbour, Tanya Adams, Vicky Kennard, Vittorio Trevitt, Rachael Jones, Jeremy Levy, Alexandra Schoolmeester, Serah Duro, May Rabuya, Deborah Jordan, Teresa Solano, Hiromi Uzu, Karen Williams, Julianne Lwanga, Linda Ekaette Reid-Amoruso, Hannah Gamlen, Robert J. Stocker, Fiona Ryan, Karina Mahiouz, Tess Cheetham, Claire Williams, Achyuta Nori, Caroline Thomas, Sivaraj Venkateshwaran, Jessica Doctor, Andrea Berlanga, Beatriz Santana-Suarez, Leigh McQueen, Priya Bhagwandin, Bee Barbini, Emily Wandolo, Tim Appleby, Lois Driver, Sophy Parr, Hongbo Deng, Julie Barber, Andrew Crowe, Chris Taylor, Mary Poulton, Vida Boateng, Marie-Pierre Klein, Caitlin O'Brien, Samuel Ohene-Adomako, Christian Buckingham, Daniel Trotman, Killian Quinn, Kate Flanagan, Verity Sullivan, Holly Middleditch, Itty Samuel, Elizabeth Hamlyn, Candice McDonald, Ana Canoso, Emeka Agbasi, Maria Liskova, Sarah Barber, Amanda Samarawickrama, Zoe Ottaway, Claire Norcross, Amelia Oliveira, Jane Minton, Gary Lamont, Ruby Cross, Gaushiya Saiyad, Shadia Ahmed, Rebecca Ashworth, Nicola Window, J. Murira, Khine Phyu, Gabriella Lindergard, Jonathan Shaw, Sarah Holland, Claire Fox, Jan Flaherty, Margaret-Anne Bevan, Valerie George, Marie Branch, Pauline Lambert, Adele Craggs, Sarah Pett, Hinal Lukha, Nina Vora, Marzia Fiorino, Maria Muller Nunez, Deirdre Sally, Erica Pool, Rebecca Matthews, Tara Stothard, Bijal Patel, Ian McVittie, Ciara Kennedy, Uli Shwab, Brendan Payne, Sarah Duncan, Jill Dixon, Mathias Schmid, Adam Evans, Christopher Duncan, Ewan Hunter, Yusri Taha, Natasha Astill, Jonathan Ainsworth, Rachel Vincent, Chloe Saad, Sarah Skinner, Hocine Azzoug, Judith Russell, Tarik Moussaoui, Emily Mabonga, Donna Ward, J. Francoise, W. Larbi, Sue Mitchell, A. Manning, V. Russell, Mark Harber, Nnenna Ngwu, Jonathan Edwards, Nargis Hemat, Tom Fernandez, Filippo Ferro, Jorge Ferreira, Alice Nightingale, Tasha Oakes-Monger, Darwin Matila, Pedro Nogueira, Victoria Mutagwanya, Catherine Emily Isitt, Helen Webb, Joyce Popoola, Kate Korley, Mark Mencias, Patricia Ribeiro, Rajeshwar Ramkhelawn, Sandra Oliva Lara, Sara Sajijad, Alan Winston, Amber Shaw, Claire Petersen, Kyle Ring, Melanie Rosenvinge, Thembi Moyo, Faith Odong, Katherine Gantert, Tina Ibe, Denis Onyango, and Teresa Hill

Subjects
Nephrology
Published
2022

3. Genetic Variants of APOL1 Are Major Determinants of Kidney Failure in People of African Ancestry With HIV

Author

Rachel K.Y. Hung, Elizabeth Binns-Roemer, John W. Booth, Rachel Hilton, Mark Harber, Beatriz Santana-Suarez, Lucy Campbell, Julie Fox, Andrew Ustianowski, Catherine Cosgrove, James E. Burns, Amanda Clarke, David A. Price, David Chadwick, Denis Onyango, Lisa Hamzah, Kate Bramham, Caroline A. Sabin, Cheryl A. Winkler, Frank A. Post, John Booth, Anele Waters, James Hand, Chris Clarke, Sarah Murphy, Maurice Murphy, Marion Campbell, Celia Richardson, Alyson Knott, Gemma Weir, Rebecca Cleig, Helena Soviarova, Lisa Barbour, Tanya Adams, Vicky Kennard, Vittorio Trevitt, Rachael Jones, Jeremy Levy, Alexandra Schoolmeester, Serah Duro, May Rabuya, Deborah Jordan, Teresa Solano, Hiromi Uzu, Karen Williams, Julianne Lwanga, Linda Ekaette Reid-Amoruso, Hannah Gamlen, Robert J. Stocker, Fiona Ryan, Karina Mahiouz, Tess Cheetham, Claire Williams, Achyuta Nori, Caroline Thomas, Sivaraj Venkateshwaran, Jessica Doctor, Andrea Berlanga, Frank Post, Leigh McQueen, Priya Bhagwandin, Bee Barbini, Emily Wandolo, Tim Appleby, Lois Driver, Sophy Parr, Hongbo Deng, Julie Barber, Andrew Crowe, Chris Taylor, Mary Poulton, Vida Boateng, Marie-Pierre Klein, Caitlin O'Brien, Samuel Ohene-Adomako, Christian Buckingham, Daniel Trotman, Killian Quinn, Kate Flanagan, Verity Sullivan, Holly Middleditch, Itty Samuel, Elizabeth Hamlyn, Candice McDonald, Ana Canoso, Emeka Agbasi, Maria Liskova, Sarah Barber, Amanda Samarawickrama, Zoe Ottaway, Claire Norcross, Amelia Oliveira, Jane Minton, Gary Lamont, Ruby Cross, Gaushiya Saiyad, Shadia Ahmed, Rebecca Ashworth, Nicola Window, J. Murira, Khine Phyu, Gabriella Lindergard, Jonathan Shaw, Sarah Holland, Claire Fox, Jan Flaherty, Margaret-Anne Bevan, Valerie George, Marie Branch, Pauline Lambert, Adele Craggs, Sarah Pett, Hinal Lukha, Nina Vora, Marzia Fiorino, Maria Muller Nunez, Deirdre Sally, Erica Pool, Rebecca Matthews, David Ashley Price, Tara Stothard, Bijal Patel, Ian McVittie, Ciara Kennedy, Uli Shwab, Brendan Payne, Sarah Duncan, Jill Dixon, Mathias Schmid, Adam Evans, Christopher Duncan, Ewan Hunter, Yusri Taha, Natasha Astill, Cheryl Winkler, Victor David, Jonathan Ainsworth, Rachel Vincent, Stephen Kegg, Chloe Saad, Sarah Skinner, Hocine Azzoug, Judith Russell, Tarik Moussaoui, Emily Mabonga, Donna Ward, J. Francoise, W. Larbi, Sue Mitchell, A. Manning, V. Russell, Fiona Burns, Nnenna Ngwu, Jonathan Edwards, Nargis Hemat, Tom Fernandez, Filippo Ferro, Jorge Ferreira, Alice Nightingale, Tasha Oakes-Monger, Darwin Matila, Pedro Nogueira, Victoria Mutagwanya, Catherine Emily Isitt, Helen Webb, Joyce Popoola, Kate Korley, Mark Mencias, Patricia Ribeiro, Rajeshwar Ramkhelawn, Sandra Oliva Lara, Sara Sajijad, Alan Winston, Amber Shaw, Claire Petersen, Kyle Ring, Melanie Rosenvinge, Thembi Moyo, Faith Odong, Katherine Gantert, Tina Ibe, Caroline Sabin, and Teresa Hill

Subjects
kidney, Nephrology, Africa, HIV, diaspora, APOL1, HIVAN
Abstract

Introduction: Variants of the APOL1 gene are associated with chronic kidney disease (CKD) in people of African ancestry, although evidence for their impact in people with HIV are sparse. Methods: We conducted a cross-sectional study investigating the association between APOL1 renal risk alleles and kidney disease in people of African ancestry with HIV in the UK. The primary outcome was end-stage kidney disease (ESKD; estimated glomerular filtration rate [eGFR] of 2, chronic dialysis, or having received a kidney transplant). The secondary outcomes included renal impairment (eGFR 2), albuminuria (albumin-to-creatinine ratio [ACR] >30 mg/mmol), and biopsy-proven HIV-associated nephropathy (HIVAN). Multivariable logistic regression was used to estimate the associations between APOL1 high-risk genotypes (G1/G1, G1/G2, G2/G2) and kidney disease outcomes. Results: A total of 2864 participants (mean age 48.1 [SD 10.3], 57.3% female) were genotyped, of whom, 354 (12.4%) had APOL1 high-risk genotypes, and 99 (3.5%) had ESKD. After adjusting for demographic, HIV, and renal risk factors, individuals with APOL1 high-risk genotypes were at increased odds of ESKD (odds ratio [OR] 10.58, 95% CI 6.22–17.99), renal impairment (OR 5.50, 95% CI 3.81–7.95), albuminuria (OR 3.34, 95% CI 2.00–5.56), and HIVAN (OR 30.16, 95% CI 12.48–72.88). An estimated 49% of ESKD was attributable to APOL1 high-risk genotypes. Conclusion: APOL1 high-risk genotypes were strongly associated with kidney disease in people of African ancestry with HIV and accounted for approximately half of ESKD cases in this cohort.

Published
2022

5. Sickle Cell Trait and Kidney Disease in People of African Ancestry With HIV

Author

Rachel K.Y. Hung, Elizabeth Binns-Roemer, John W. Booth, Rachel Hilton, Julie Fox, Fiona Burns, Mark Harber, Andrew Ustianowski, Lisa Hamzah, James E. Burns, Amanda Clarke, David A. Price, Stephen Kegg, Denis Onyango, Beatriz Santana-Suarez, Lucy Campbell, Kate Bramham, Claire C. Sharpe, Caroline A. Sabin, Cheryl A. Winkler, Frank A. Post, John Booth, Anele Waters, James Hand, Chris Clarke, Sarah Murphy, Maurice Murphy, Marion Campbell, Celia Richardson, Alyson Knott, Gemma Weir, Rebecca Cleig, Helena Soviarova, Lisa Barbour, Tanya Adams, Vicky Kennard, Vittorio Trevitt, Rachael Jones, Jeremy Levy, Alexandra Schoolmeester, Serah Duro, May Rabuya, Deborah Jordan, Teresa Solano, Hiromi Uzu, Karen Williams, Julianne Lwanga, Linda Ekaette Reid-Amoruso, Hannah Gamlen, Robert J. Stocker, Fiona Ryan, Karina Mahiouz, Tess Cheetham, Claire Williams, Achyuta Nori, Caroline Thomas, Sivaraj Venkateshwaran, Jessica Doctor, Andrea Berlanga, Frank Post, Leigh McQueen, Priya Bhagwandin, Bee Barbini, Emily Wandolo, Tim Appleby, Lois Driver, Sophy Parr, Hongbo Deng, Julie Barber, Andrew Crowe, Chris Taylor, Mary Poulton, Vida Boateng, Marie-Pierre Klein, Caitlin O’Brien, Samuel Ohene-Adomako, Christian Buckingham, Daniel Trotman, Killian Quinn, Kate Flanagan, Verity Sullivan, Holly Middleditch, Itty Samuel, Elizabeth Hamlyn, Candice McDonald, Ana Canoso, Emeka Agbasi, Maria Liskova, Sarah Barber, Amanda Samarawickrama, Zoe Ottaway, Claire Norcross, Amelia Oliveira, Jane Minton, Gary Lamont, Ruby Cross, Gaushiya Saiyad, Shadia Ahmed, Rebecca Ashworth, Nicola Window, J. Murira, Khine Phyu, Gabriella Lindergard, Jonathan Shaw, Sarah Holland, Claire Fox, Jan Flaherty, Margaret-Anne Bevan, Valerie George, David Chadwick, Marie Branch, Pauline Lambert, Adele Craggs, Sarah Pett, Hinal Lukha, Nina Vora, Marzia Fiorino, Maria Muller Nunez, Deirdre Sally, Erica Pool, Rebecca Matthews, David Ashley Price, Tara Stothard, Bijal Patel, Ian McVittie, Ciara Kennedy, Uli Shwab, Brendan Payne, Sarah Duncan, Jill Dixon, Mathias Schmid, Adam Evans, Christopher Duncan, Ewan Hunter, Yusri Taha, Natasha Astill, Cheryl Winkler, Victor David, Jonathan Ainsworth, Rachel Vincent, Chloe Saad, Sarah Skinner, Hocine Azzoug, Judith Russell, Tarik Moussaoui, Emily Mabonga, Donna Ward, J. Francoise, W. Larbi, Sue Mitchell, A. Manning, V. Russell, Nnenna Ngwu, Jonathan Edwards, Nargis Hemat, Tom Fernandez, Filippo Ferro, Jorge Ferreira, Alice Nightingale, Tasha Oakes-Monger, Darwin Matila, Pedro Nogueira, Victoria Mutagwanya, Catherine Cosgrove, Catherine Emily Isitt, Helen Webb, Joyce Popoola, Kate Korley, Mark Mencias, Patricia Ribeiro, Rajeshwar Ramkhelawn, Sandra Oliva Lara, Sara Sajijad, Alan Winston, Amber Shaw, Claire Petersen, Kyle Ring, Melanie Rosenvinge, Thembi Moyo, Faith Odong, Katherine Gantert, Tina Ibe, Caroline Sabin, and Teresa Hill

Subjects
Nephrology
Abstract

Sickle cell trait (SCT) has been associated with chronic kidney disease (CKD) in African Americans, although evidence for its impact in Africans and people with HIV is currently lacking. We conducted a cross-sectional study investigating the association between SCT and kidney disease in people of African ancestry with HIV in the UK.The primary outcome was estimated glomerular filtration rate (eGFR) 60 ml/min per 1.73 mA total of 2895 participants (mean age 48.1 [SD 10.3], 57.2% female) were included, of whom 335 (11.6%) had SCT and 352 (12.2%) had eGFR 60 ml/min per 1.73 mOur results extend previously reported associations between SCT and kidney disease to people with HIV. In people of African ancestry with HIV, these associations were largely restricted to those with

Published
2021

9. Mechanical behavior of damaged laminated composites plates and shells: Higher-order Shear Deformation Theories

Author

Michele Bacciocchi, Erasmo Viola, Francesco Tornabene, Nicholas Fantuzzi, Tornabene, Francesco, Fantuzzi, Nichola, Bacciocchi, Michele, Viola, Erasmo, A.J.M. Ferreira, W. Larbi, J.-F. Deu, F. Tornabene, N. Fantuzzi, Tornabene, F., Fantuzzi, N., Bacciocchi, M., and Viola, E.

Subjects
Materials science, Higher-order shear deformation theories, Gaussian, Ceramics and Composite, Parametric investigation, 02 engineering and technology, Laminated and sandwich structure, Plates and Shell, Ellipse, Variable Mechanical Propertie, symbols.namesake, 0203 mechanical engineering, Laminated composites, Damage Modeling, Higher-order Shear Deformation Theorie, Civil and Structural Engineering, Parametric statistics, Natural frequencie, Numerical Analysis, Higher-order shear deformation theorie, Order (ring theory), Function (mathematics), Mechanics, 021001 nanoscience & nanotechnology, Quadrature (mathematics), 020303 mechanical engineering & transports, Damage modelling, Ceramics and Composites, symbols, 0210 nano-technology, Differential (mathematics)
Abstract

A higher-order structural model based on a Unified Formulation is employed to investigate the mechanical behavior of laminated composite plates and shells with variable elastic properties. The variability in hand is obtained by means of peculiar mathematical laws that allow to describe linear, sine-wave, and exponential variations of the mechanical properties. In addition, two-dimensional functions are also introduced to define more complex variations. For instance, by choosing the Gaussian function is possible to model a damage that can affect a shell structure. In fact, a generic damage within the reference domain can be modeled by setting properly the parameters of the distribution at issue and imposing an abrupt deterioration of the engineering elastic constants. In particular, the size and intensity damage effects on the structural response are investigated through a set of parametric analyses. Similar considerations can be extended to the case of an ellipse shaped function introduced for the same purpose. Since a numerical analysis is performed, the governing equations are solved by the Generalized Differential Quadrature (GDQ) method due to its accuracy and stability features. The same numerical approach is used to evaluate the geometric properties of the doubly-curved surfaces in hand, which denote the reference domains. In addition, it should be specified that the differential geometry provides all the analytical definitions for an accurate description of these shells with variable radii of curvature.

Published
2018

10. Taylor Meshless Method for bending and buckling of thin plates

Author

Haitao Tian, Michel Potier-Ferry, Farid ABED-MERAIM, Laboratoire d'Etude des Microstructures et de Mécanique des Matériaux (LEM3), Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM), A.J.M. Ferreira, W. Larbi, J.-F. Deu, F. Tornabene, and N. Fantuzzi

Subjects
Matériaux [Sciences de l'ingénieur], Bending, Mécanique [Sciences de l'ingénieur], Buckling, Taylor Meshless Method, [PHYS.MECA]Physics [physics]/Mechanics [physics], Modélisation et simulation [Informatique], Sciences de l'ingénieur, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, Asymptotic Numerical Method, Trefftz Method, [SPI]Engineering Sciences [physics], [PHYS.MECA.STRU]Physics [physics]/Mechanics [physics]/Structural mechanics [physics.class-ph], [PHYS.MECA.SOLID]Physics [physics]/Mechanics [physics]/Solid mechanics [physics.class-ph], Bifurcation, PDEs, Thin anisotropic plates
Abstract

International audience; This paper introduces a new meshless method named Taylor Meshless Method (TMM) using Taylor series to deduce the shape functions. Next the problem is discretized by point-collocation only on the boundary and without integration. The discrete boundary problem is solved by least-squares method. In this talk, this method is applied to bending and buckling of isotropic and anisotropic plates. The shape functions are polynomials that coincide with harmonic polynomials in the case of Laplace equation. These polynomials are computed numerically by solving the PDE approximately in the sense of Taylor series. Of course, this leads to an error that decreases asymptotically with the degree. TMM can be considered as a Trefftz Method, but we search approximated solutions in the sense of Taylor series while Trefftz Method is generally based on exact solutions of the PDE. As a counterpart, one is able to build this complete family of approximated solutions, whatever be the studied equation. A strong reduction of the number of degrees of freedom is the main advantage of this class of discretization techniques. The main drawback is the ill-conditioning of the final matrix, what can limit the size of the solved problem, but it was established that TMM is able to solve large scale problems. In the case of nonlinear PDEs as Föppl-Von Karman plate models, one applies first a linearization technique as Newton iterative technique. Here we apply Asymptotic Numerical Method. Next the resulting linear equations have variable coefficients are they are solved by TMM. Several linear and nonlinear numerical results will be presented for isotropic and anisotropic laminated plates.

Published
2017

11. Composite Structures of Arbitrary Shape by Using Nonlinear Isogeometric Mapping

Author

FANTUZZI, NICHOLAS, TORNABENE, FRANCESCO, BACCIOCCHI, MICHELE, VIOLA, ERASMO, A.J.M. Ferreira, W. Larbi, J.-F. Deu, F. Tornabene, N. Fantuzzi, Fantuzzi, N., Tornabene, F., Bacciocchi, M., and Viola, E.

Subjects
Composite Structures, NURBS, Finite Element Method, Strong Formulation Finite Element Method, Isogeometric Mapping
Abstract

Composite structures have been widely used in several engineering applications nowadays. Their use is mainly in advanced components at all scales from small to large, such as in bio medical engineering and civil and aerospace engineering. In the former body parts are involved in the design process, whereas in the latter large roof and fuselages are studied for industrial applications. Since the 1950s several numerical methods have been introduced to study such structures, most of these techniques were related to weak form finite element methods wherein the variational form of the governing equation is analyzed. Unfortunately, such numerical schemes might have numerical issues due to geometry approximation and convergence behavior. For solving such problems strong form numerical approaches were introduced in order to have higher accuracy trends and “almost exact” geometry approximation since such scheme is based on collocation points. Among all the recent developed strong form techniques the Differential Quadrature (DQ) method has been deeply investigated in the last years. However, the DQ method can only be applied to geometries of regular shape such as domains in Cartesian, polar or orthogonal curvilinear coordinates. In order to be able to generalize such approach the mapping technique and the domain decomposition method must be introduced. The authors developed a strong form finite element technique which considers Not Uniform Rational B-Splines (NURBS) to described geometrically the edges of the elements within the given mesh. Such curves are taken from CAD software so that the resulting geometric approximation of the physical structure is more accurate and flexible than other classic mapping approaches.

Published
2017

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