https://bio.m ox.polimi.it/prin-meeting-cardiovascular-modelling/

\n END:VEVENT BEGIN:VEVENT UID:j5aqhvifvinpev17ti4evi5rgs@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:http://www.lnm.mw.tum.de/lacm2015/ DTSTART;VALUE=DATE:20150312 DTEND;VALUE=DATE:20150314 SEQUENCE:0 SUMMARY:LACM 2015 URL:https://bio.mox.polimi.it/event/lacm-2015/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nhttp://www.ln m.mw.tum.de/lacm2015/

\n END:VEVENT BEGIN:VEVENT UID:gu40j8s83thkbn49v42redp63k@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:StaTalk on Biostatistics is the first event of the StaTalks! se ries organized by the young section of the Italian Statistical Society (y- SIS).\nStatalks are a series of one-day workshop aimed at early career sta tisticians\, i.e.\, master degree students\, people carrying out a PhD\, post-docs and young researchers. StaTalks are a fantastic opportunity to s hare knowledge on advanced topics of statistics in a relaxed and friendly atmosphere. The hosting research group will propose tutorials\, seminars a nd interactive round tables on the main fields of research and application it is concerned.\nParticipants can contribute bringing their own experien ce through presentations\, ideas\, poster and material to be shared in the debate.\nA StaTalk will be held every 6 months in a different city in Ita ly. \n*No fees are due\, but registration is mandatory (deadline March 30t h)*\nProgram and details available at:\nhttps://sites.google.com/site/youn gsocietaitalianastatistica/events/statalk/statalk_unimi\nYou can actively join the afternoon tables bringing poster\, presentations\, videos\, … any thing! Let’s write to the Tables managers:\n-> The Statistics of the Genom e –\n Marzia Cremona (marziaangela.cremona@polimi.it)\n Alice Parodi (alice.parodi@polimi.it)\n-> Urns\, Coins and Clinical Trials –\n Andr ea Ghiglietti (andrea.ghiglietti@unimi.it)\n-> Intensive Statistical Compu ting with R\n Francesco Grossetti (francesco.grossetti@polimi.it)\n Paolo Zanini (paolo.zanini@polimi.it) DTSTART;VALUE=DATE:20150424 DTEND;VALUE=DATE:20150425 LOCATION:Department of Mathematics\, Università degli Studi di Milano\, via Saldini 50\, Milano (Italy) SEQUENCE:0 SUMMARY:StaTalk on Biostatistics URL:https://bio.mox.polimi.it/event/statalk-on-biostatistics/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nStaTalk on Bi
ostatistics is the first event of the StaTalks! series organized by the yo
ung section of the Italian Statistical Society (y-SIS).

\nStatalks ar
e a series of one-day workshop aimed at early career statisticians\, i.e.\
, master degree students\, people carrying out a PhD\, post-docs and youn
g researchers. StaTalks are a fantastic opportunity to share knowledge on
advanced topics of statistics in a relaxed and friendly atmosphere. The ho
sting research group will propose tutorials\, seminars and interactive rou
nd tables on the main fields of research and application it is concerned.<
br />\nParticipants can contribute bringing their own experience through p
resentations\, ideas\, poster and material to be shared in the debate.

\nA StaTalk will be held every 6 months in a different city in Italy. \n

*No fees are due\, but registration is mandatory (deadline March 30 th)*

\nProgram and details available at:

\nhttps://sites.google
.com/site/youngsocietaitalianastatistica/events/statalk/statalk_unimi

You can actively join the afternoon tables bringing poster\, presenta tions\, videos\, … anything! Let’s write to the Tables managers:

\n-
> The Statistics of the Genome –

\n Marzia Cremona (marziaangela.c
remona@polimi.it)

\n Alice Parodi (alice.parodi@polimi.it)

\n
-> Urns\, Coins and Clinical Trials –

\n Andrea Ghiglietti (andrea
.ghiglietti@unimi.it)

\n-> Intensive Statistical Computing with R

\n Francesco Grossetti (francesco.grossetti@polimi.it)

\n Pao
lo Zanini (paolo.zanini@polimi.it)

http://www.g la.ac.uk/schools/mathematicsstatistics/events/conferences/softtissuemodell ing2/

\n END:VEVENT BEGIN:VEVENT UID:gnot53k0tii5jdprilspt4aark@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:http://www.compbiomed.net/2015/index.htm DTSTART;VALUE=DATE:20150629 DTEND;VALUE=DATE:20150702 SEQUENCE:0 SUMMARY:CMBE2015 URL:https://bio.mox.polimi.it/event/cmbe2015/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nhttp://www.co mpbiomed.net/2015/index.htm

\n END:VEVENT BEGIN:VEVENT UID:6udrejd2k9fnukr30f4jed0dl0@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:36th Annual Conference of the International Society for Clinica l Biostatistics\n23 – 27 August 2015\, Utrecht\, The Netherlands \nMore de tails at:\nhttp://www.iscb2015.info/ DTSTART;VALUE=DATE:20150823 DTEND;VALUE=DATE:20150828 LOCATION:Utrecht Science Park Heidelberglaan 11 3584 CS Utrecht SEQUENCE:0 SUMMARY:ISCB 2015\, Utrecht URL:https://bio.mox.polimi.it/event/iscb-2015-utrecht/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\n36th Annual C
onference of the International Society for Clinical Biostatistics

\n2
3 – 27 August 2015\, Utrecht\, The Netherlands

More details at:**\nhttp://www.iscb2015.info/**

http://congr ess.cimne.com/ICCB2015/frontal/default.asp

\n END:VEVENT BEGIN:VEVENT UID:03267A81-87E6-4E83-A701-C1CDEC0B4286 DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:The next CEN International Nanomedicine Symposium will take pla ce on Monday\, September 21st\, 2015\, at Palazzo Lombardia in Milan.\nIn this third edition of our annual meeting\, a multidisciplinary dialogue wi ll involve international top-scientists while presenting several works tha t have been carried out within the CEN project framework.\nIn attachment y ou will find the Symposium program\, including this year a poster session. \nParticipation is free upon online registration at http://nanomedicen.eu/ cen-congress-2015/register.\nFor further information\, please check our we bsite http://nanomedicen.eu/cen-congress-2015/program or contact our staff at info@nanomedicen.eu.\nContact:\nchiara@giverso.com DTSTART;VALUE=DATE:20150921 DTEND;VALUE=DATE:20150922 LOCATION:Palazzo Lombardia\, Piazza Città di Lombardia\, 1\, Milano\, Itali a SEQUENCE:0 SUMMARY:CEN International Nanomedicine Symposium URL:https://bio.mox.polimi.it/event/cen-international-nanomedicine-symposiu m/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nThe next CEN International Nanomedicine Symposium will take place on Monday\, September 21st\, 2015\, at Palazzo Lombardia in Milan.

\nIn this third editio n of our annual meeting\, a multidisciplinary dialogue will involve intern ational top-scientists while presenting several works that have been carri ed out within the CEN project framework.

\nIn attachment you will fi nd the Symposium program\, including this year a poster session.

\nP articipation is free upon online registration at http://nanomedicen.eu/cen -congress-2015/register.

\nFor further information\, please check ou r website http://nanomedicen.eu/cen-congress-2015/program or contact our s taff at info@nanomedicen.eu.

\nContact:

\nchiara@giverso.com

ISCB2016 – 37 th annual conference of the International Society of Clinical Biostatistic s

\n\n

The ISCB 2016 conference will provide a scientific for um for international exchange of theory\, methods and applications of clin ical biostatistics among biostatisticians\, epidemiologists and other medi cal researchers.

\n END:VEVENT BEGIN:VEVENT UID:shc2crf0usod5luctm31d8v500@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:http://www.sbm.org.br/jointmeeting-italy DTSTART;VALUE=DATE:20160829 DTEND;VALUE=DATE:20160903 SEQUENCE:0 SUMMARY:!st Joint meeting Brazil-Italy in Mathematics URL:https://bio.mox.polimi.it/event/st-joint-meeting-brazil-italy-in-mathem atics/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nhttp://www.sb m.org.br/jointmeeting-italy

\n END:VEVENT BEGIN:VEVENT UID:mc9jcit7mhs63v4fqv2vjr3ogo@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION: DTSTART;VALUE=DATE:20160908 DTEND;VALUE=DATE:20160910 SEQUENCE:0 SUMMARY:ESB-ITA Thematica Symposium “Frontier Biomechanical Challenges in C ardiovascular Physiopathology” URL:https://bio.mox.polimi.it/event/esb-ita-thematica-symposium-frontier-bi omechanical-challenges-in-cardiovascular-physiopathology/ END:VEVENT BEGIN:VEVENT UID:4e3lij13j5rrkp9sijr78c6cp4@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:http://www.bcamath.org/en/workshops/qbio2017 DTSTART;VALUE=DATE:20170221 DTEND;VALUE=DATE:20170223 SEQUENCE:0 SUMMARY:Third BCAM Workshop on Quantitative Biomedicine for Health and Dise ase URL:https://bio.mox.polimi.it/event/third-bcam-workshop-on-quantitative-bio medicine-for-health-and-disease/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nhttp://www.bc amath.org/en/workshops/qbio2017

\n END:VEVENT BEGIN:VEVENT UID:5scnmhq2fhu63il7etq2gbbvq0@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:http://dmf.unicatt.it/mathsfromthebody/ DTSTART;VALUE=DATE:20170529 DTEND;VALUE=DATE:20170601 SEQUENCE:0 SUMMARY:Maths from the body\, Brescia URL:https://bio.mox.polimi.it/event/maths-from-the-body-brescia/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nhttp://dmf.un icatt.it/mathsfromthebody/

\n END:VEVENT BEGIN:VEVENT UID:785u6su4jkc71s0vnm5s4cc7co@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:http://www.cism.it/courses/C1705/ DTSTART;VALUE=DATE:20170612 DTEND;VALUE=DATE:20170617 SEQUENCE:0 SUMMARY:23rd CISM-IUTAM International Summer School on “Growth and Remodeli ng in Soft Biological Tissue” URL:https://bio.mox.polimi.it/event/23rd-cism-iutam-international-summer-sc hool-on-growth-and-remodeling-in-soft-biological-tissue/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nhttp://www.ci sm.it/courses/C1705/

\n END:VEVENT BEGIN:VEVENT UID:b8fjqdens3a8aa5q6367ssvlao@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:http://congressi.iac.cnr.it/mathtech-mobi2017 DTSTART;VALUE=DATE:20170626 DTEND;VALUE=DATE:20170629 SEQUENCE:0 SUMMARY:INdAM workshop “Modeling and computational approaches to Biology an d Medicine” (MOBI 2017) URL:https://bio.mox.polimi.it/event/indam-workshop-modeling-and-computation al-approaches-to-biology-and-medicine-mobi-2017/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nhttp://congre ssi.iac.cnr.it/mathtech-mobi2017

\n END:VEVENT BEGIN:VEVENT UID:ho0g2n0ufe5ok5n984i7escc8o@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:http://595.euromech.org/ DTSTART;VALUE=DATE:20170829 DTEND;VALUE=DATE:20170901 SEQUENCE:0 SUMMARY:Colloquium 595 Biomechanics and computer assisted surgery meets med ical reality\, Lille URL:https://bio.mox.polimi.it/event/colloquium-595-biomechanics-and-compute r-assisted-surgery-meets-medical-reality-lille/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nhttp://595.eu romech.org/

\n END:VEVENT BEGIN:VEVENT UID:beuv182la29ojvvkbhcfdu3fss@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:Prof. Ajit Yoganathan\,\nThe Wallace H. Coulter Distinguished F aculty Chair in Biomedical Engineering\n& Regents Professor\nAssoc. Chair for Research\nWallace H. Coulter School of Biomedical Engineering\nGeorgia Institute of Technology & Emory University\nDirector\, Center for Innovat ive Cardiovascular Technologies\nCollege of Engineering\, Georgia Institut e of Technology\nTitle : Using Basic Science and Engineering to Gain Mecha nistic Insight for Reconstructive Mitral Valve Surgery DTSTART;TZID=Europe/Rome:20141015T100000 DTEND;TZID=Europe/Rome:20141015T110000 LOCATION:Aula LaBS\, Politecnico di Milano SEQUENCE:0 SUMMARY:Seminar : Using Basic Science and Engineering to Gain Mechanistic I nsight for Reconstructive Mitral Valve Surgery URL:https://bio.mox.polimi.it/event/seminar-using-basic-science-and-enginee ring-to-gain-mechanistic-insight-for-reconstructive-mitral-valve-surgery/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nProf. Ajit Yo
ganathan\,

\nThe Wallace H. Coulter Distinguished Faculty Chair in Bi
omedical Engineering

\n& Regents Professor

\nAssoc. Chair for Re
search

\nWallace H. Coulter School of Biomedical Engineering

\nG
eorgia Institute of Technology & Emory University

\nDirector\, Center
for Innovative Cardiovascular Technologies

\nCollege of Engineering\
, Georgia Institute of Technology

Title : Using Basic Science and Engineering to Gain Mechanistic Insight for Reconstructive Mitral Valve Su rgery

\n END:VEVENT BEGIN:VEVENT UID:0fg0vobgto7qucl1v9k0g45uck@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION: DTSTART;TZID=Europe/Rome:20141019T180000 DTEND;TZID=Europe/Rome:20141019T190000 SEQUENCE:0 SUMMARY: URL:https://bio.mox.polimi.it/event/145420/ END:VEVENT BEGIN:VEVENT UID:sflknu6gs7m0mngldp6jgc6bpk@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:“An asymptotic homogenization approach for multiphase linear el astic composites with discontinuous material properties.” DTSTART;TZID=Europe/Rome:20141216T100000 DTEND;TZID=Europe/Rome:20141216T110000 SEQUENCE:0 SUMMARY:Seminario Raimondo Penta URL:https://bio.mox.polimi.it/event/seminario-raimondo-penta/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\n“An asymptot ic homogenization approach for multiphase linear elastic composites with d iscontinuous material properties.”

\n END:VEVENT BEGIN:VEVENT UID:abr715thtmlavgftcua8447do8@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION: DTSTART;TZID=Europe/Rome:20141219T103000 DTEND;TZID=Europe/Rome:20141219T113000 SEQUENCE:0 SUMMARY:11:30 MOX meeting URL:https://bio.mox.polimi.it/event/1130-mox-meeting/ END:VEVENT BEGIN:VEVENT UID:k4mooh13fpue2vmf863kfggm04@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:Titolo : Three-dimensional imaging of embryonic developme nt\nRelatore : prof. Andrea Bassi\, Dip. Fisica\, Politecnico di Milano\nA bstract:\nOptical Tomography is a three dimensional imaging technique whic h\, similarly to x-ray computed tomography\, is based on the acquisition o f a sequence of optical images of the sample from several orientations. Th e acquired images\, or projections\, are combined to reconstruct the 3D vo lume of the sample\, typically using a backprojection algorithm.\nThe semi nar describes recent developments for in-vivo Optical Tomography\, towards high resolution imaging of the anatomy of translucent biological samples such as zebrafish embryos. Novel contrast mechanisms\, based on blood cell motion and muscular tissue birefringence are discussed\, together with th eir applications in developmental biology.\nThe combination of Optical Tom ography with Selective Plane Illumination Microscopy (SPIM)\, a 3D fluores cence microscopy technique is then described. Optical tomography integrate d with SPIM was used to image zebrafish embryos over several hours of deve lopment\, to detect\, segment\, track and automatically register single or gans during the course of long term time lapse acquisitions. DTSTART;TZID=Europe/Rome:20150120T100000 DTEND;TZID=Europe/Rome:20150120T113000 LOCATION:Aula Saleri 6° piano MOX @ Dipartimento di Matematica Politecnico di Milano SEQUENCE:0 SUMMARY:Seminario BioMOX A. Bassi: Three-dimensional imaging of embryonic d evelopment URL:https://bio.mox.polimi.it/event/seminario-biomox-a-bassi-three-dimensio nal-imaging-of-embryonic-development/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nTitolo :
Three-dimensional imaging of embryonic development

\nRelatore : pro
f. Andrea Bassi\, Dip. Fisica\, Politecnico di Milano

Abstract:

\nOptical Tomography is a three dimensional imaging technique which\, s
imilarly to x-ray computed tomography\, is based on the acquisition of a s
equence of optical images of the sample from several orientations. The acq
uired images\, or projections\, are combined to reconstruct the 3D volume
of the sample\, typically using a backprojection algorithm.

\nThe sem
inar describes recent developments for in-vivo Optical Tomography\, toward
s high resolution imaging of the anatomy of translucent biological samples
such as zebrafish embryos. Novel contrast mechanisms\, based on blood cel
l motion and muscular tissue birefringence are discussed\, together with t
heir applications in developmental biology.

\nThe combination of Opti
cal Tomography with Selective Plane Illumination Microscopy (SPIM)\, a 3D
fluorescence microscopy technique is then described. Optical tomography in
tegrated with SPIM was used to image zebrafish embryos over several hours
of development\, to detect\, segment\, track and automatically register si
ngle organs during the course of long term time lapse acquisitions.

Relatore: And rea Remuzzi – Ist M. Negri\, Ranica (BG)

\nTitolo: Hemodynamics of v ascular access for hemodialysis

\nAbstract: Function and duration of vascular access for hemodialysis is the most important clinical problem i n these patients. Arteriovenous fistula with native vessels is the most re commended strategy\, but it is affected by early failure and short duratio n. Vascular access failure is predominantly related to development of inti mal hyperplasia. We then studied the role of hemodynamics on development o f initial hyperplasia in arteriovenous fistulas using idealized vascular m odels as well as patient-specific models.

\n END:VEVENT BEGIN:VEVENT UID:dm8da77hh9h29me1mi34s52a6o@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:SEMINAR\nKateryna Makova (Pentz Professor of Biology -The Penns ylvania State University)\nTitle:\nAccurate Typing of SHORT Tandem Repeats from genome-wide sequencing data and its applications\nAbstract:\nShort T andem Repeats (STRs) are implicated in dozens of human genetic diseases an d contribute significantly to genome variation and instability. Yet profil ing STRs from short-read sequencing data is challenging because of their h igh sequencing error rate. Here we developed STR-FM\, Short Tandem Repeat profiling using Flank-based Mapping\, a computational pipeline that can de tect the full spectrum of STR alleles from short-read data\, can adapt to emerging read-mapping algorithms\, and can be applied to heterogeneous gen etic samples (e.g.\, tumors\, viral populations\, and genomes of organelle s). We used STR-FM to study STR error rates and patterns in publicly avail able human\, and in-house generated ultra-deep plasmid\, sequencing datase ts. We discovered that STRs sequenced with a PCR-free protocol have up to 9-fold fewer errors than those sequenced with a PCR-containing protocol. W e constructed an error correction model for genotyping STRs that can assig n genotypes correctly to 98-1!\n 00% of STRs and can distinguish heterozyg ous alleles containing STRs with consecutive repeat numbers. Applying our model and pipeline to Illumina sequencing data with 100-bp reads\, we coul d confidently genotype several disease-related long trinucleotide STRs. Ut ilizing this pipeline\, for the first time we determined the genome-wide S TR germ-line mutation rate from a deeply sequenced human pedigree. More mu tations originated in the male germ line. Additionally\, we built a tool t hat recommends minimum sequencing depth for accurate STR genotyping\, depe nding on repeat length of interest and sequencing read length. The require d read depth increases with STR length and is lower for a PCR-free protoco l. This suite of tools addresses the pressing challenges surrounding STR g enotyping\, and thus is of wide interest to researchers investigating dise ase-related STRs and STR evolution.\nContact: anna.paganoni@polimi.it DTSTART;TZID=Europe/Rome:20150310T103000 DTEND;TZID=Europe/Rome:20150310T113000 LOCATION:Aula Saleri VI Piano Dipartimento di Matematica\, Politecnico di M ilano SEQUENCE:0 SUMMARY:seminario BIOMOX : K. Makova URL:https://bio.mox.polimi.it/event/seminario-biomox-k-makova/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nSEMINAR

\nKateryna Makova (Pentz Professor of Biology -The Pennsylvania State Univ
ersity)

Title:

\nAccurate Typing of SHORT Tandem Repeats from
genome-wide sequencing data and its applications

Abstract:

\nShort Tandem Repeats (STRs) are implicated in dozens of human genetic di
seases and contribute significantly to genome variation and instability. Y
et profiling STRs from short-read sequencing data is challenging because o
f their high sequencing error rate. Here we developed STR-FM\, Short Tande
m Repeat profiling using Flank-based Mapping\, a computational pipeline th
at can detect the full spectrum of STR alleles from short-read data\, can
adapt to emerging read-mapping algorithms\, and can be applied to heteroge
neous genetic samples (e.g.\, tumors\, viral populations\, and genomes of
organelles). We used STR-FM to study STR error rates and patterns in publi
cly available human\, and in-house generated ultra-deep plasmid\, sequenci
ng datasets. We discovered that STRs sequenced with a PCR-free protocol ha
ve up to 9-fold fewer errors than those sequenced with a PCR-containing pr
otocol. We constructed an error correction model for genotyping STRs that
can assign genotypes correctly to 98-1!

\n 00% of STRs and can distin
guish heterozygous alleles containing STRs with consecutive repeat numbers
. Applying our model and pipeline to Illumina sequencing data with 100-bp
reads\, we could confidently genotype several disease-related long trinucl
eotide STRs. Utilizing this pipeline\, for the first time we determined th
e genome-wide STR germ-line mutation rate from a deeply sequenced human pe
digree. More mutations originated in the male germ line. Additionally\, we
built a tool that recommends minimum sequencing depth for accurate STR ge
notyping\, depending on repeat length of interest and sequencing read leng
th. The required read depth increases with STR length and is lower for a P
CR-free protocol. This suite of tools addresses the pressing challenges su
rrounding STR genotyping\, and thus is of wide interest to researchers inv
estigating disease-related STRs and STR evolution.

Contact: anna.p aganoni@polimi.it

\n END:VEVENT BEGIN:VEVENT UID:r42tohr0tsphdnb3j28o2tn2u0@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:SEMINAR\nValentina Balbi (Phd – CNRS and Sorbonne Universités\, Université Paris 6)\nTitle:\nMorphoelastic Control of Gastro-Intestinal O rganogenesis:\nTheoretical Predictions and Numerical Insights\nAbstract:\n With nine meters in length\, the gastrointestinal tract is not only our lo ngest\, but also our structurally most diverse organ. During embryonic dev elopment\, it evolves as a bilayered tube with an inner endodermal lining and an outer esodermal layer. Its inner surface displays a wide variety o f morphological patterns\, which are closely correlated to digestive funct ion. However\, the evolution of these intestinal patterns remains poorly u nderstood. Here we show that geometric and mechanical factors can explain intestinal pattern formation. Using the nonlinear field theories of mechan ics\, we model surface orphogenesis as the instability problem of constrai ned differential growth. To allow for internal and external expansion\, we model the gastrointestinal tract with homogeneous Neumann boundary condit ions. To establish estimates for the folding pattern at the onset of foldi ng\, we perform a linear stability analysis supplemented by the perturbati on theory. To predict pattern evolution in the post-buckling regime\, we p erform a series of nonlinear finite element simulations. Our model explai ns why longitudinal folds emerge in the esophagus with a thick and stiff o uter layer\, whereas circumferential folds emerge in the jejunum with a th inner and softer outer layer. In intermediate regions like the feline esop hagus\, longitudinal and circumferential folds emerge simultaneously. Our model could serve as a valuable tool to explain and predict alterations in esophageal morphology as a result of developmental disorders or certain d igestive pathologies including food allergies.\nContact: pasquale.ciarlett a@polimi.it\n davide.ambrosi@polimi.it DTSTART;TZID=Europe/Rome:20150323T100000 DTEND;TZID=Europe/Rome:20150323T110000 LOCATION:III Piano Dipartimento di Matematica\, Politecnico di Milano SEQUENCE:0 SUMMARY:seminario BIOMOX : V. Balbi – Morphoelastic Control of Gastro-Intes tinal Organogenesis: Theoretical Predictions and Numerical Insights URL:https://bio.mox.polimi.it/event/seminario-biomox-v-balbi-morphoelastic- control-of-gastro-intestinal-organogenesis-theoretical-predictions-and-num erical-insights/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nSEMINAR

\nValentina Balbi (Phd – CNRS and Sorbonne Universités\, Université Paris
6)

Title:

\nMorphoelastic Control of Gastro-Intestinal Organo
genesis:

\nTheoretical Predictions and Numerical Insights

Abs
tract:

\nWith nine meters in length\, the gastrointestinal tract is n
ot only our longest\, but also our structurally most diverse organ. During
embryonic development\, it evolves as a bilayered tube with an inner endo
dermal lining and an outer esodermal layer. Its inner surface displays a
wide variety of morphological patterns\, which are closely correlated to d
igestive function. However\, the evolution of these intestinal patterns re
mains poorly understood. Here we show that geometric and mechanical factor
s can explain intestinal pattern formation. Using the nonlinear field theo
ries of mechanics\, we model surface orphogenesis as the instability probl
em of constrained differential growth. To allow for internal and external
expansion\, we model the gastrointestinal tract with homogeneous Neumann b
oundary conditions. To establish estimates for the folding pattern at the
onset of folding\, we perform a linear stability analysis supplemented by
the perturbation theory. To predict pattern evolution in the post-buckling
regime\, we perform a series of nonlinear finite element simulations. Ou
r model explains why longitudinal folds emerge in the esophagus with a thi
ck and stiff outer layer\, whereas circumferential folds emerge in the jej
unum with a thinner and softer outer layer. In intermediate regions like t
he feline esophagus\, longitudinal and circumferential folds emerge simult
aneously. Our model could serve as a valuable tool to explain and predict
alterations in esophageal morphology as a result of developmental disorder
s or certain digestive pathologies including food allergies.

Conta
ct: pasquale.ciarletta@polimi.it

\n davide.ambrosi@polimi
.it

SEMINAR

\nYang Liu (Department of Statistics of Penn State University)

Tit
le:

\nExploiting structure to reduce and integrate high-dimensional\,
under-sampled genomics data.

Abstract:

\nAnalysis of high-di
mensional\, under-sampled data has become increasingly important in Genomi
cs with its expanding repertoire of high-throughput technologies. For many
regression-like analyses\, dimension reduction in the predictor space can
be very effective. The most commonly used approaches assume that predicto
rs and samples are similar in nature and can simultaneously participate in
the reduction. However\, recent high-throughput genomic data is often het
erogeneous and structured. Exploiting known structure in samples and predi
ctors when performing dimension reduction can be an avenue for integrating
data collected through multiple studies and diverse high-throughput platf
orms.

\nTo address this challenge\, we propose a new Sufficient Dimen
sion Reduction (SDR) approach\; Structured Ordinary Least Squares (sOLS).
sOLS combines ideas from existing SDR literature to merge reductions perfo
rmed within subgroups of samples and/or predictors. As a part of our propo
sal\, we developed group-wise OLS (gOLS) to efficiently perform SDR for gr
ouped predictors. Simulation studies and a first application to ENCODE gen
omic data show promising performance for our methodology. Our work holds t
he promise of providing the Genomics community with an effective data redu
ction and integration approach\, and also having broad applicability to co
mplex data from other scientific fields.

Contact:

\nsimone.va
ntini@polimi.it

Speaker: prof . JF GErbeau – INRIA\, Paris\, France

\nTitle: Approximated Lax Pair for reduced order modeling. Application to electrophysiology

\nAbst ract: A reduced-order model algorithm\, called ALP\, is proposed to solve nonlinear evolution partial differential equations. It is based on approxi mations of generalized Lax pairs. Contrary to other reduced-order methods\ , like Proper Orthogonal Decomposition\, the basis on which the solution i s searched for evolves in time according to a dynamics specific to the pro blem. It is therefore well-suited to solving problems with progressive fro nt or wave propagation. Another difference with other reduced-order method s is that it is not based on an off-line / on-line strategy. Numerical exa mples are shown for the FKPP equations and for the bidomain model of elect rophysiology. This work was done in collaboration with Damiano Lombardi an d Elisa Schenone.

\n END:VEVENT BEGIN:VEVENT UID:g58o1jd56kfpksri839bcol4hg@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION: DTSTART;TZID=Europe/Rome:20150408T140000 DTEND;TZID=Europe/Rome:20150408T150000 SEQUENCE:0 SUMMARY:seminario BIOMOX\, aula Saleri : dr Pini [cardiologist at Ospedale Sacco – MI] URL:https://bio.mox.polimi.it/event/seminario-biomox-aula-saleri-dr-pini-ca rdiologist-at-ospedale-sacco-mi/ END:VEVENT BEGIN:VEVENT UID:hfutosss17me235ogahbcd6sng@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:SEMINAR\nD. Fuster (Université Pierre et Marie Curie\, Paris) \nTitle:\nModeling and simulation of the influence of microbubbles on macr oscale processes\nAbstract:\nThe collective response of small bubbles to e xternal pressure changes is a topic of interest in various processes such the elaboration of new contrast agents\, lithotripsy\, systems involving wave propagation and underwater explosions.\nModeling the influence of the smallest scales (of the order of microns and below) on large scales is c rucial to unveil the intrinsic interaction mechanisms between pressure wav es and the response of bubbles.\nIn this talk I will present some recent a dvances on the modeling and simulation of complex systems containing bubbl es. Based on volume-averaged equations\, a subgrid model is added to acco unt for a bubble\, or multiple bubbles\, within each computational cell. The model converges to the solution of ensemble-averaged bubbly flow equat ions for weak oscillations and monodisperse systems. In the other extreme\ , it also converges to the theoretical solution for a single oscillating b ubble\, and captures the bubble radius evolution and the pressure disturb ance induced in the liquid. Compared to previous models based on volume a nd phase averaging\, the new model extends the range of void fractions tha t can be reliably simulated and\, for low enough void fractions\,reproduce s the results of the polydisperse phase-averaged model with much smaller c omputational expense. The new numerical results allow us to gain new insi ght into the effect of direct bubble-bubble interactions as well as polydi spersity in the response of bubble clusters. \nFinally\, I will discuss so me recent progress on the generalization of the model to more complex sit uations and some challenges when modeling the influence of nanometric bubb les at large scales.\nContact: pasquale.ciarletta@polimi.it DTSTART;TZID=Europe/Rome:20150414T093000 DTEND;TZID=Europe/Rome:20150414T103000 LOCATION:Aula Saleri VI Piano Dipartimento di Matematica\, Politecnico di M ilano SEQUENCE:0 SUMMARY:seminario BIOMOX : D. Fuster (CNRS) URL:https://bio.mox.polimi.it/event/seminario-biomox-d-fuster-cnrs/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nSEMINAR

\nD. Fuster (Université Pierre et Marie Curie\, Paris)

Title:

\nModeling and simulation of the influence of microbubbles on macroscale
processes

Abstract:

\nThe collective response of small bubbl
es to external pressure changes is a topic of interest in various processe
s such the elaboration of new contrast agents\, lithotripsy\, systems inv
olving wave propagation and underwater explosions.

\nModeling the inf
luence of the smallest scales (of the order of microns and below) on larg
e scales is crucial to unveil the intrinsic interaction mechanisms between
pressure waves and the response of bubbles.

In this talk I will p resent some recent advances on the modeling and simulation of complex syst ems containing bubbles. Based on volume-averaged equations\, a subgrid mo del is added to account for a bubble\, or multiple bubbles\, within each c omputational cell. The model converges to the solution of ensemble-averag ed bubbly flow equations for weak oscillations and monodisperse systems. I n the other extreme\, it also converges to the theoretical solution for a single oscillating bubble\, and captures the bubble radius evolution and the pressure disturbance induced in the liquid. Compared to previous mode ls based on volume and phase averaging\, the new model extends the range o f void fractions that can be reliably simulated and\, for low enough void fractions\,reproduces the results of the polydisperse phase-averaged model with much smaller computational expense. The new numerical results allow us to gain new insight into the effect of direct bubble-bubble interactio ns as well as polydispersity in the response of bubble clusters.

\nFinally\, I will discuss some recent progress on the generalization of the model to more complex situations and some challenges when modeling the i nfluence of nanometric bubbles at large scales.

\nContact: pasquale. ciarletta@polimi.it

\n END:VEVENT BEGIN:VEVENT UID:r5dgf111k6iqif8h6e6g9v4ti0@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION: DTSTART;TZID=Europe/Rome:20150427T123000 DTEND;TZID=Europe/Rome:20150427T133000 SEQUENCE:0 SUMMARY:Incontro BioMOX\, aula Saleri – Seminario interno Diana Bonomi URL:https://bio.mox.polimi.it/event/incontro-biomox-aula-saleri-seminario-i nterno-diana-bonomi/ END:VEVENT BEGIN:VEVENT UID:8smbpe2fi75933oqkp84ed87qc@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:SEMINAR\nA. Tagliabue (PoliMi) \nTitle:\nModelling blood flows in an idealized left ventricle: Nitsche’s method for the treatment of the valves as generalized boundary conditions\nAbstract:\nIn this talk\, we fo cus on the description of the fluid dynamics of blood flows inside idealiz ed human left ventricles (LV)\, which represents a complex phenomena to be accurately modelled from both the mathematical and numerical points of vi ew.\nBy adopting a simplified model for the LV\, represented by a truncate d prolate spheroid with prescribed wall movement\, we introduce the formul ation of a proper set of boundary conditions (BCs) for the Navier-Stokes e quations allowing a simplified but realistic treatment of both the mitral and aortic valves.\n Indeed\, in the framework of [Juntunen and Stenberg\, Mathematics of Computation\, 2009]\, we propose a Nitsche’s method for th e efficient numerical treatment of the opening and closing stages of the v alves\, which are associated to different types of BCs\, ideally switching from natural to essential\, and viceversa.\n Moreover\, we include in our formulation boundary stabilization terms preventing the numerical instabi lities eventually associated to backflow divergence.\nIn order to highligh t the effectiveness of the proposed Nitsche’s method\, we present and disc uss some numerical results for blood flows in two dimensional idealized LV .\nContact:\nanna.tagliabue@polimi.it DTSTART;TZID=Europe/Rome:20150511T080000 DTEND;TZID=Europe/Rome:20150511T090000 LOCATION:Aula Saleri VI Piano Dipartimento di Matematica\, Politecnico di M ilano SEQUENCE:0 SUMMARY:seminario BIOMOX : A. Tagliabue URL:https://bio.mox.polimi.it/event/seminario-biomox-a-tagliabue/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nSEMINAR

\nA. Tagliabue (PoliMi)

Title:

\nModelling blood flows in an
idealized left ventricle: Nitsche’s method for the treatment of the valve
s as generalized boundary conditions

Abstract:

\nIn this talk
\, we focus on the description of the fluid dynamics of blood flows inside
idealized human left ventricles (LV)\, which represents a complex phenome
na to be accurately modelled from both the mathematical and numerical poin
ts of view.

\nBy adopting a simplified model for the LV\, represented
by a truncated prolate spheroid with prescribed wall movement\, we introd
uce the formulation of a proper set of boundary conditions (BCs) for the N
avier-Stokes equations allowing a simplified but realistic treatment of bo
th the mitral and aortic valves.

\n Indeed\, in the framework of [Jun
tunen and Stenberg\, Mathematics of Computation\, 2009]\, we propose a Nit
sche’s method for the efficient numerical treatment of the opening and clo
sing stages of the valves\, which are associated to different types of BCs
\, ideally switching from natural to essential\, and viceversa.

\n Mo
reover\, we include in our formulation boundary stabilization terms preven
ting the numerical instabilities eventually associated to backflow diverge
nce.

\nIn order to highlight the effectiveness of the proposed Nitsch
e’s method\, we present and discuss some numerical results for blood flows
in two dimensional idealized LV.

Contact:

\nanna.tagliabue@p
olimi.it

SEMINAR

\nMarcelo Epstein (Universita’ di Calgary (Canada))

Title:

\n
Material groupoids in remodeling and aging

Contact:

\ndavide.
ambrosi@polimi.it

SEMINAR

\nJacques Ohayon (University of Savoie Mont-Blanc (Chambery) )

Ti
tle:

\nBiomechanics of Coronary Atherosclerotic Plaque Rupture: Progr
ess\, Challenges and New Directions

Abstract:

\nThe leading c
ause of major morbidity and mortality in most

\ncountries around the
world is atherosclerotic cardiovascular disease\, most commonly caused by
the rupture of a vulnerable plaque (VP). The challenge for the new generat
ion of in vivo clinical imaging methods is that prediction of the VP ruptu
re requires not only an accurate description of plaque morphology\, but al
so a precise knowledge of mechanical properties of plaque constituents. In
deed\, such knowledge will likely allow a precise evaluation of the thin-c
ap fibro-atheroma peak stress amplitude\, which is a reliable predictor of
VP rupture. The clinical success of a surgical intervention depends on kn
owledge of whether a lesion is at risk for rupture and can be responsible
for the development of neurological or cardiovascular events\, respectivel
y.

\nThe medical history and paraclinical tests are sometimes insuffi
cient to resolve this uncertainty.

\nHence\, it is essential to devel
op\, test and validate novel invasive and noninvasive clinical diagnostic
methods based on continuum mechanics theory combining strain and elasticit
y reconstruction techniques for a better in vivo evaluation of the risk of
vulnerable carotid and coronary plaque ruptures. The proposed imaging met
hod appears promising for the evaluation of VP rupture. Furthermore\, the
performance for the stabilization of VP using new treatment

\nstrateg
ies could be investigated by using such imaging technique.

Contact
:

\ndavide.ambrosi@polimi.it

SEMINAR

\nMatteo Santacesaria (Università di Helsinki)

Title:

\nSome
inverse boundary value problems in two dimensions: theory and applications
.

Abstract:

\nIn this talk we will focus on two inverse boun
dary value problems\, the Calderón problem and the Gelfand-Calderon proble
m. The first concerns the reconstruction of an electrical conductivity fro
m voltage and current measurements on the boundary of an object\; its rela
ted imaging method is called Electrical Impedance Tomography and has appli
cations from medical imaging to non destructive testing. In the Gelfand-Ca
lderon problem one wants to reconstruct a potential in the Schrödinger equ
ation from some information of its solutions at the boundary of a domain (
Dirichlet to Neumann map). This problem can be seen as a model for acousti
c tomography\, namely with applications in geophysical prospecting.

\nWe will first discuss theoretical properties of these problems\, in part
icular their ill-posedness and stability estimates. Then we will present s
ome recent numerical reconstruction results. First a numerical implementat
ion for the reconstruction of a potential in the Schrödinger equation from
high energy data\; this new algorithm clearly shows how the resolution in
creases with the energy. Then we will present a new imaging technique base
d on electrical measurements which allows the reconstruction of inclusions
inside a body. Its main feature is the ability to identify inclusions ins
ide inclusions and the main application is a new method for early detectio
n of brain strokes.

Contact:

\nelena.beretta@polimi.it

SEMINAR

\nFrancesco Scardulla (ISMETT\, Palermo)

Title:

\nA prelimina
ry fluid-dynamic computational study on celiac trunk in patients with

\nventricular assist device.

Abstract:

\nLVADs (Left Ventric
ular Assist Devices) are a promising alternative to heart transplantation
for patients with heart failure as they act as an artificial pump. These d
evices cause a syndrome characterized by gastro-intestinal bleeding. An an
alysis was performed to find out the wall shear stress in the celiac trunk
(the group of arteries that supply blood to the digestive system) in orde
r to find a correlation between the induced patology and the alterated hem
odynamic conditions.

Contact:

\nchristian.vergara@polimi.it\n
END:VEVENT
BEGIN:VEVENT
UID:j9of5uptua9r9vh2l32c3fe3o8@google.com
DTSTAMP:20170923T233235Z
CATEGORIES:
CONTACT:
DESCRIPTION:SEMINAR\nProf. Jolanda Wentzel (head of Biomechanics Laboratory
at ERASMUS MC\, Rotterdam\, The Netherlands).\nTitle:\nBiomechanics and a
therosclerosis in human coronary arteries.\nAbstract:\nAt the Biomechanics
Laboratory we study the effect of mechanical stresses on generation\, pro
gression\, destabilization and rupture of atherosclerotic plaques. Insight
in these processes helps to improve selection\, diagnosis and treatment o
f patients with atherosclerosis. In order to investigate the relationship
between biomechanical parameters and vascular disease the 3D geometry of t
he lumen and vessel wall is required\, which serves as input for computati
onal modeling. We developed technology to 3D reconstruct the coronary arte
rial lumen and wall by fusion of various in vivo imaging modalities\, incl
uding angiography\, IVUS\, MSCT and VH-IVUS. The first 3D reconstructions
of human coronary arteries in vivo were based on a combination of angiogra
phy and intravascular ultrasound. We use this technique to performed image
based modeling of shear stress and wall stress to study the relationship
between biomechanical parameters and localization of atherosclerosis and p
laque destabilization. Recently\, we started studies on stent deployment i
n diseased human coronary arteries in close collaboration with LaBS\, Poli
tecnico di Milano\, Italy and Ghent University\, Belgium.\nContact:\ne.cut
ri83@gmail.com
DTSTART;TZID=Europe/Rome:20150707T083000
DTEND;TZID=Europe/Rome:20150707T093000
LOCATION:LaBS @ Laboratory of Biological Structure Mechanics Chemistry\, Ma
terials and Chemical Engineering Department 'Giulio Natta' Politecnico di
Milano
SEQUENCE:0
SUMMARY:seminario LABS: Prof. J. Wentzel
URL:https://bio.mox.polimi.it/event/seminario-labs-prof-j-wentzel/
X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\n

SEMINAR

\nProf. Jolanda Wentzel (head of Biomechanics Laboratory at ERASMUS MC\, R
otterdam\, The Netherlands).

Title:

\nBiomechanics and athero
sclerosis in human coronary arteries.

Abstract:

\nAt the Biom
echanics Laboratory we study the effect of mechanical stresses on generati
on\, progression\, destabilization and rupture of atherosclerotic plaques.
Insight in these processes helps to improve selection\, diagnosis and tre
atment of patients with atherosclerosis. In order to investigate the relat
ionship between biomechanical parameters and vascular disease the 3D geome
try of the lumen and vessel wall is required\, which serves as input for c
omputational modeling. We developed technology to 3D reconstruct the coron
ary arterial lumen and wall by fusion of various in vivo imaging modalitie
s\, including angiography\, IVUS\, MSCT and VH-IVUS. The first 3D reconstr
uctions of human coronary arteries in vivo were based on a combination of
angiography and intravascular ultrasound. We use this technique to perform
ed image based modeling of shear stress and wall stress to study the relat
ionship between biomechanical parameters and localization of atheroscleros
is and plaque destabilization. Recently\, we started studies on stent depl
oyment in diseased human coronary arteries in close collaboration with LaB
S\, Politecnico di Milano\, Italy and Ghent University\, Belgium.

Contact:

\ne.cutri83@gmail.com

SEMINAR

\nP. Zunino

\n(MEMS\, University of Pittsburgh & MOX\, Politecnico di
Milano)

Title:

\nAn embedded multiscale approach for studyin
g flow and transport in tumors

Abstract:

\nReduced models of
flow or mass transport in heterogeneous media are often adopted in the com
putational approach when the geometrical configuration of the system is to
o complex. A paradigmatic example in this respect is blood flow through a
network of capillaries surrounded by a porous interstitium. We numerically
address this biological system by a computational model based on a multis
cale resolution of embedded domains. We avoid resolving the complex 3D geo
metry of the submerged vessels by representing them as a network of 1D cha
nnels.

Cancer employs transport as a fundamental mechanism of coor dination and communication and the physics of mass transport within body c ompartments and across biological barriers differentiates cancer from heal thy tissues. Mass and heat transport are also at the basis of cancer treat ment. Delivery of diagnostic and therapeutic agents differs dramatically b etween tumor and normal tissues. In contrast to healthy tissue\, tumors ex hibit interstitial hypertension\, which is caused by the high permeability of tumor vessels in combination with the lack of functional lymphatic ves sels in the tumor interstitial space.

\nThe analysis of fluid\, mass and heat exchange in vascularized tumors is a relevant application of the model proposed here. We will use it to study fluid exchange between the c apillaries and the interstitial volume\, as well as to compare different m odalities to deliver treatment to tumors\, including using nanoparticles a nd hyperthermia.

\nContact:

\nchristian.vergara@polimi.it

36th Annual Conference o f the International Society for Clinical Biostatistics

\n END:VEVENT BEGIN:VEVENT UID:5658A2DE-85E4-43D6-B083-02798251BA99 DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:SEMINAR:\nM.Lancellotti (MOX-PoliMi)\nTitle:\nTowards large edd y simulations in stenotic carotid bifurcations\nAbstract:\nIn this work we consider Large Eddy Simulations (LES) for haemodynamic applications\, in particular in the context of stenotic human carotids\, since transitional/ turbulent phenomena can occur in this situation. We compare two different subgrid-scale models\, i.e. the dynamic Sigma and the dynamic mixed model\ , with a suitable Direct Numerical Simulation (DNS) able to correctly reso lve the shear layer detaching from the stenosis. We consider P2-P2 finite elements for space discretization and a SUPG stabilization able to circumv ent the LBB condition is adopted. A second order BDF scheme is used for ti me discretization with a semi-implicit treatment of the convective and sub grid non-linear terms. Patient-specific boundary data obtained by\nEcho-Co lor Doppler measurements are used to prescribe boundary conditions. We pre sent several numerical results with the aim of investigating the way turbu lence affect hemodynamic indices such as wall shear stress. Vorticity and energy spectra are computed to better assess the turbulence activity.\nCon tact:\nchristian.vergara@polimi.it DTSTART;TZID=Europe/Rome:20150918T093000 DTEND;TZID=Europe/Rome:20150918T103000 LOCATION:Aula Saleri VI Piano Dipartimento di Matematica\, Politecnico di M ilano SEQUENCE:0 SUMMARY:seminario BIOMOX : M.Lancellotti URL:https://bio.mox.polimi.it/event/seminario-biomox-m-lancellotti/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nSEMINAR:

\nM.Lancellotti (MOX-PoliMi)

Title:

\nTowards large eddy sim
ulations in stenotic carotid bifurcations

Abstract:

\nIn this
work we consider Large Eddy Simulations (LES) for haemodynamic applicatio
ns\, in particular in the context of stenotic human carotids\, since trans
itional/turbulent phenomena can occur in this situation. We compare two di
fferent subgrid-scale models\, i.e. the dynamic Sigma and the dynamic mixe
d model\, with a suitable Direct Numerical Simulation (DNS) able to correc
tly resolve the shear layer detaching from the stenosis. We consider P2-P2
finite elements for space discretization and a SUPG stabilization able to
circumvent the LBB condition is adopted. A second order BDF scheme is use
d for time discretization with a semi-implicit treatment of the convective
and subgrid non-linear terms. Patient-specific boundary data obtained by<
br />\nEcho-Color Doppler measurements are used to prescribe boundary cond
itions. We present several numerical results with the aim of investigating
the way turbulence affect hemodynamic indices such as wall shear stress.
Vorticity and energy spectra are computed to better assess the turbulence
activity.

Contact:

\nchristian.vergara@polimi.it

SEMINAR:

\nU.Morbiducci (Politecnico di Torino)

Title:

\nDescriptors
of arterial hemodynamics

Abstract:

\nKnowledge of blood flow
mechanics is a critical issue (1) for an in depth understanding of the rel
ationships between hemodynamic factors and arterial homeostasis and (2) fo
r the identification of those flow features that lead to changes in the fu
nction and health of vessels. While from one side there is clear evidence
that regions of disrupted flow are correlated to\, e.g.\, the localization
of atherosclerosis\, the development of aneurysms and non-physiological t
ransport of species\, on the opposite cause-effect links still do not emer
ge clearly. To allow for a more effective and valuable understanding of bl
ood flow structures and mechanisms in complex four-dimensional cardiovascu
lar flows\, in recent years a large number of hemodynamic parameters have
surfaced in the literature\, enabling the understanding of arterial hemody
namics and of the role of streaming blood in the development of pathologic
al events. Here\, a survey of recently proposed methods to characterize in
! travascular fluid structures in arteries\, in particular helical flow\,
is presented and their relationship with (1) widely adopted disturbed shea
r indicators as well as (2) emerging indicators of the relevance of wall s
hear stress multidirectionality in the distribution of vascular lesions\,
are discussed together with open questions on their clinical utility.

Contact:

\nchristian.vergara@polimi.it

SEMINAR:

\nMaurizio Quadrio (Dipartimento di Ingegneria Aerospaziale\, Politecnico
di Milano)

Title:

\nFluidodinamica delle cavità nasali

Abstract:

\nLe patologie che inducono difficolta’ respiratorie nas
ali rappresentano una situazione molto comune\, e comportano elevati costi
sociali ed economici. Nonostante cio’\, la loro gestione eventualmente

\nanche chirurgica risente della difficolta’ di correlare le anomalie a
natomiche (e le loro eventuali correzioni chirurgiche) alle caratteristich
e della corrente fluida all’interno delle cavita’

\nnasali. Negli ult
imi anni la fluidodinamica computazionale (CFD) ha assunto un ruolo cresce
nte nella descrizione della corrente fluida all’interno delle alte vie res
piratorie.

Il seminario descrive i passi essenziali di una procedu
ra patient-specific\, basata sulla CFD\, che stiamo sviluppando per suppor
tare i chirurghi ORL nella loro pratica clinica quotidiana. La procedura p
arte da una scansione TAC del massiccio facciale del paziente\, e produce
un dettagliato campo fluidodinamico tridimensionale e dipendente dal tempo
all’interno delle cavita’ nasali. Requisiti essenziali della procedura so
no:

\ni) la sua “economicita'” (nel senso piu’ generale del termine)\
, per poterla realisticamente utilizzare nella pratica clinica quotidiana\
;

\nii) la robustezza e affidabilita’ delle sue previsioni\, relativa
mente non solo a quantita’ globali (come la portata\, o la resistenza nasa
le) ma anche ai dettagli della corrente fluida nelle aree in cui il chirur
go deve operare.

Dopo una breve descrizione dei passaggi procedura
li che conducono dalla TAC al risultato fluidodinamico\, verranno commenta
ti i risultati di analisi fluidodinamiche ad alta fedelta’ (DNS\, LES) e l
e fasi

\npreparatorie di un esperimento di laboratorio. L’esperimento
\, i cui risultati saranno fondamentali per la taratura della procedura CF
D\, prevede la misura mediante tecniche PIV dell’intero campo di velocita’

\nin un modello in scala 2:1 anatomicamente realistico (derivato anc
h’esso da una TAC).

Contact:

\ndavide.ambrosi@polimi.it

SEMINAR:

\nMikel Landajuela (INRIA\, Paris)

Title:

\nNitsche-XFEM for
the coupling of an incompressible fluid with immersed thin-walled structu
res

Abstract:

\nIn this work we present a Nitsche-XFEM method
for fluid-structure interaction problems involving a thin-walled elastic
structure immersed in an incompressible fluid. The fluid domain is discret
ized with an unstructured mesh not fitted to the solid mid-surface mesh. T
he thin-walled nature of the immersed solid introduces jumps on the fluid
stresses which\, respectively\, results in weak and strong discontinuities
of the velocity and pressure fields across the interface. The approximati
on spaces allow to capture these discontinuous features through suitable e
nrichment of the intersected elements (see [1]). The kinematic/kinetic flu
id-solid coupling is enforced consistently using a variant of Nitsche’s me
thod involving cut elements. Robustness with respect to arbitrary interfac
e/element intersections is guaranteed through a ghost penalty stabilizatio
n (see [2]).

\nFor the temporal discretization\, several coupling sch
emes with different degrees of fluid-solid splitting (implicit\, semi-impl
icit and explicit) are investigated. In particular\, we address the extens
ion of the explicit coupling paradigm introduced in [3] to the unfitted me
sh framework. The stability and convergence properties of the methods prop
osed are rigorously analyzed in a representative linear setting. Several n
umerical examples\, involving static and moving interfaces\, illustrate th
e performance of the methods.

[1] A. Hansbo and P. Hansbo. A finit
e element method for the simula- tion of strong and weak discontinuities i
n solid mechanics. Comput. Methods Appl. Mech. Engrg.\, 193(33-35):3523–35
40\, 2004.

\n[2] E. Burman and P. Hansbo\, Fictitious domain methods
using cut elements: III. A stabilized Nitsche method for Stokes problem. M
2AN Math. Model. Numer. Anal.\, 48(3):859–874\, 2014.

\n[3] M. Fernán
dez\, J. Mullaert\, M. Vidrascu\, Explicit Robin-Neumann schemes for the c
oupling of incompressible fluids with thin-walled structures\, Comput. Met
hods Appl. Mech. Engrg. 267 (2013) 566–593.

Contact:

\nchrist
ian.vergara@polimi.it

SEMINAR:

\nAndrea Ghiglietti (Università degli Studi di Milano\, Dipartimento di M
atematica “F. Enriques”)

Title:

\nInteracting Generalized Pòl
ya Urn Systems

Abstract:

\nWe consider a system of interactin
g Generalized Pòlya Urns (GPUs) having irreducible mean replacement matric
es. The interaction is modeled through the conditional probabilities to sa
mple the colors from the urns\, that are defined as convex combinations of
the urn proportions in the system. The weights of these combinations are
gathered in the interacting matrix\, whose structure individuates subsyste
ms of urns evolving with different behaviors: (i) the leading systems\, wh
ose dynamics is independent of the rest of the system (ii) the following s
ystems\, whose dynamics “follows” the evolution of other urns of the syste
m. We provide a complete description of the asymptotic behavior of the sys
tem by proving theoretical results on the sequence of the urn proportions.
Specifically\, we establish the limiting proportions\, the convergence ra
tes and the Central Limit Theorems in both the leading and the following s
ystems. The main techniques adopted to prove these results consist in revi
siting the urn dynamics in the stochastic approximation framework and real
izing a detailed analysis on the eigen-structure of the interacting matrix
and the mean replacement matrices. Finally\, we present the expected resu
lts in the case of diagonal mean replacement matrix and we discuss further
extensions concerning a random and time dependent interacting matrix.

SEMINAR:

\nEmiliano Votta (DEIB\, Politecnico di Milano)

Title:

\nFin
ite element modeling of the mitral valve from clinical imaging: a tool to
support the optimization of surgical treatment

Abstract:

\nTh
e mitral valve is a particularly complex apparatus that separates the left
atrium from the left ventricle and guarantees unidirectional blood flow f
rom the former to the latter.

\nMitral valve patholgies have a high p
revalence and usually require surgical treatment\, repair being preferred
to substitution whenever possible. At the same time\, though\, mitral repa
ir can be complex and the corresponding clinicl outcomes are not always sa
tisfactory. For this reason the improvement of repair techniques and devic
es remains a focal clinical and research activity.

\nIn this process\
, numerical modelling has been used since the ’90s to gain insight into mi
tral valve biomechanics\, so to better understand mitral valve pathophysio
logy and support the development of more effective surgical approaches. In
the last decade in particular\, numerical models based on medical imaging
have been developed\, exploting the detailed anatomical information yield
ed by medical images. This evolution of the modelling approach has paved t
he way towards the use of numerical models as a support tool for the patie
nt-specific tailoring of mitral valve surgical repair.

\nIn the semin
ar\, the modeling activity carried out in this field by the Biomechanics R
esearch Group at DEIB\, Politecnico di Milano\, will be presented\; the po
tential of the developed modeling approach will be exemplified through rec
ent clinical applications\, and emphasis will focused on current and futur
e developments.

Contact:

\nchristian.vergara@polimi.it

SEMINAR:

\nGiuliana Indelicato (Dipartimento di Matematica\, Università degli Stud
i di Torino)

Title:

\nMathematical models of self-assembling
polypeptide nanoparticles

Abstract:

\nIn this talk I will dis
cuss a mathematical framework that allows to predict and classify the layo
ut of polypeptidic building blocks in synthetized nanoparticles. I will
focus on the *de-novo *system called SAPN (self-assembling polypeptide nan
oparticles) which self assembles from multiple copies of a polypeptidic bu
ilding block and has been designed to act as a repetitive antigen display
system in a novel generation of vaccines. Clinical trials on a vaccine aga
inst malaria based on this technology are due to start soon.

\nThe ch
aracterization of these particles by experimental methods only is not suff
icient to completely elucidate the morphology of the assembled structure.
Moreover\, the classical theory of Caspar and Klug for the

\narrangem
ents of protein clusters in viral capsids cannot be used because the SAPNs
particles exhibit more than the twelve pentagonal clusters allowed in suc
h classification. In this presentation I will show that graph-theoretical
methods can provide important insights into the geometry of such nanoparti
cles. I will study

\nand classify the topology of the protein network
s using tools from planar graph theory. Special attention will be devoted
to symmetric particles\,which can be fully described and classified.

Contact:

\ndavide.ambrosi@polimi.it

SEMINAR:

\nLev V. Beloussov (Lab of Developmental Biophysics\, Faculty of Biology\
, Moscow State University)

Title:

\nMorphomechanical approach
to embryonic development

Abstract:

\nMorphogenesis\, that is
\, creation of new forms and structures in development of organisms is the
main but still poorly understood component of ontogenesis. By the modern
criteria\, it belongs to the processes of self-organization\, which may be
simulated by two kinds of models: chemo-diffusional and those based upon
mechanical forces/stresses. Among the advantages of the latter ones are na
turally arisen feedbacks with 3-dimensional geometry\, permitting to repro
duce the complication of shapes without introducing each time ad hoc taken
interventions.

\nAs a first step\, a plausibility of mechanical mode
ls was supported by discovering the patterns of mechanical stresses (MS) i
n embryonic tissues\, regularly arranged in space/time of development. The
next step was to explore whether the already established MS can affect ne
wly generated mechanical forces within cells creating thus the feedback lo
ops able to drive forth morphogenesis. Experimental and model evidences on
the existence of such feedbacks will be presented.

\nRecently\, the
interest to morphomechanical approaches was greatly enhanced by discovery
of mechanosensitive genes participating in development of Drosophila\, fis
hes and amphibians. Taken together\, the data obtained during several last
decades strongly argue for a fundamental role of mechanically based feedb
acks in regulating development of organisms on different structural levels
.

Contact:

\npasquale.ciarletta@polimi.it

SEMINAR:

\nPaolo Decuzzi\, Ph.D (Laboratory of Nanotechnology for Precision Medici
ne Italian Institute of Technology\, Genova)

Title:

\nMULTIFU
NCTIONAL POLYMERIC NANOCONSTRUCTS: FROM IN-SILICO TO IN-VIVO

Abstr
act:

\nMultifunctional nanoconstructs are particle-based nano-scale s
ystems designed for the ‘smart’ delivery of therapeutic and imaging agents
. The Laboratory of Nanotechnology for Precision Medicine synthesizes poly
meric nanoconstructs with different sizes\, ranging from a few tens of nan
ometers to a few microns\; shapes\, including spherical\, cubical and disc
oidal\; surface properties\, with positive\, negative\, neutral coatings\;
and mechanical stiffness\, varying from that of cells to rigid\, inorgani
c materials\, such as iron oxide. These are the 4S parameters – size\, sha
pe\, surface\, stiffness – which can be precisely tuned in the synthesis p
rocess enabling disease- and patient-specific designs of multifunctional n
anoconstructs.

\nIn this lecture\, the application of these nanoconst
ructs to the detection and treatment of cancer lesions and cardiovascular
diseases\, such as thrombosis and atherosclerosis\, is discussed. The cont
ribution of the 4S parameters in modulating nanoconstruct sequestration by
the mononuclear phagocyte system\, organ specific accumulation\, and bloo
d longevity is also critically presented. These polymeric nanoconstructs c
an be loaded with a variety of therapeutic payloads – anti-cancer molecule
s (docetaxel\, paclitaxel\, doxorubicin)\, anti-inflammatory molecules (cu
rcumin\, diclofenac\, celecoxib) and small biologicals (peptides\, siRNAs\
, miRNAs)\; and imaging agents – optical probes\; Gd and iron oxide nanopa
rticles for MR imaging\; and radio-isotopes for Nuclear Imaging.

\nFu
rthermore\, the lecture presents on the fabrication and testing of microfl
uidic chips for analyzing the vascular and extravascular mass transport\,
over multiple spatial and temporal scales\, of molecules\, nanoparticles a
nd cells. These microfluidic-chips can help in elucidating biophysical mec
hanisms modulating progression and regression of various diseases\, such a
s cancer\, cardiovascular and neurodegenerative\, as well as in developing
organ-on-a-chip systems for rapid drug and nanomedicine screenings and ti
ssue regeneration.

Contact:

\npaolo.zunino@polimi.it

SEMINAR:

\nMikel Landajuela\, MOX\, Dipartimento di Matematica\, Politecnico di Mi
lano

Title:

\nCoupling schemes and unfitted mesh methods for
fluid-structure interaction

Abstract:

\nThis work is devoted
to the development and analysis of efficient numerical algorithms for the
simulation of mechanical systems involving the interaction of a deformable
thin-walled structure with an internal or surrounding incompressible flui
d flow.

\nIn the first part\, we introduce two new classes of explici
t coupling schemes using fitted fluid and solid meshes. The methods propos
ed combine a certain (parameter free) Robin-consistency in the system with
(i) a projection-based time-marching in the fluid or (ii) second-order ti
me-stepping in both the fluid and the solid. The stability properties of t
he methods are analyzed within representative linear settings. This part i
ncludes also a comprehensive numerical study in which state-of-the-art cou
pling schemes (including some of the methods proposed herein) are compared
and validated against the results of an experimental benchmark.

\nIn
the second part\, we consider unfitted mesh formulations. These approache
s are more versatile at simulating problems with large interface deflectio
ns and/or topological changes. The spatial discretization in this case is
based on variants of Nitsche’s method with cut elements. Robustness with r
espect to arbitrary interface intersections is guaranteed through suitable
stabilization. For a fictitious domain setting using overlapping meshes\,
we present two new classes of splitting schemes which exploit the aforeme
ntioned interface

\nRobin-consistency in the unfitted frame- work. Th
e semi-implicit or explicit nature of the splitting in time is dictated by
the order in which the spatial and time discretizations are performed. In
the case of the coupling with immersed structures\, weak and strong disco
ntinuities across the interface are allowed for the velocity and pressure\
, respectively. Stability and error estimates are provided\, using energy
arguments within a linear setting. A series of numerical tests\, involving
static and moving interfaces\, illustrates the performance of the differe
nt methods proposed.

Contact:

\nchristina.vergara@polimi.it\n
END:VEVENT
BEGIN:VEVENT
UID:pl36k9t4pajfbtqahu6rc0pd1c@google.com
DTSTAMP:20170923T233235Z
CATEGORIES:
CONTACT:
DESCRIPTION:SEMINAR:\nNicholas Tarabelloni\, Lab MOX – Dipartimento di Mate
matica\, Politecnico di Milano\nTitle:\nStatistical assessment and calibra
tion of numerical models with functional response\nAbstract:\nThanks to th
e rise in computational resources that are increasingly becoming available
\, numerical models of all fields are experiencing a growth of complexity
and realism. This is especially the case for mathematical models dealing w
ith biomedical phenomena\, whose goal is to describe the behaviour of phys
iological processes of human beings. To this aim\, it is now possible to c
ombine them with diverse and complex data coming from real experiments\, h
ospital collections and surveys in order to enhance the modelling. This is
of extreme importance for the development of a personalised medicine prac
tice able to instruct clinicians and recommend treatments for targeted pat
ients.\nWithin this context\, we will focus on the problem of assessing th
e quality and calibrating numerical models producing functional observatio
ns\, i.e. quantity of interest that can naturally be thought as continuous
ly depending on some variable (e.g. time). To this aim\, we will present a
general statistical framework based on depth measures and spatial quantil
es for multi-dimensional data which is able to naturally and non-parametri
cally exploit a whole collection of real measurements\, to drive the calib
ration towards multiple possible goals and finally to enhance the agreemen
t between simulated data and real data. We will show an application to the
calibration of ODE and PDE based numerical models for the simulation of p
hysiological ECG traces to a dataset of hospital recordings.\nContact:\nch
ristian.vergara@polimi.it
DTSTART;TZID=Europe/Rome:20160630T093000
DTEND;TZID=Europe/Rome:20160630T110000
LOCATION:Aula Saleri VI Piano Dipartimento di Matematica\, Politecnico di M
ilano
SEQUENCE:0
SUMMARY:Seminario biomox Tarabelloni
URL:https://bio.mox.polimi.it/event/seminario-biomox-tarabelloni/
X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\n

SEMINAR:

\nNicholas Tarabelloni\, Lab MOX – Dipartimento di Matematica\, Politecni
co di Milano

Title:

\nStatistical assessment and calibration
of numerical models with functional response

Abstract:

\nThan
ks to the rise in computational resources that are increasingly becoming a
vailable\, numerical models of all fields are experiencing a growth of com
plexity and realism. This is especially the case for mathematical models d
ealing with biomedical phenomena\, whose goal is to describe the behaviour
of physiological processes of human beings. To this aim\, it is now possi
ble to combine them with diverse and complex data coming from real experim
ents\, hospital collections and surveys in order to enhance the modelling.
This is of extreme importance for the development of a personalised medic
ine practice able to instruct clinicians and recommend treatments for targ
eted patients.

\nWithin this context\, we will focus on the problem o
f assessing the quality and calibrating numerical models producing functio
nal observations\, i.e. quantity of interest that can naturally be thought
as continuously depending on some variable (e.g. time). To this aim\, we
will present a general statistical framework based on depth measures and s
patial quantiles for multi-dimensional data which is able to naturally and
non-parametrically exploit a whole collection of real measurements\, to d
rive the calibration towards multiple possible goals and finally to enhanc
e the agreement between simulated data and real data. We will show an appl
ication to the calibration of ODE and PDE based numerical models for the s
imulation of physiological ECG traces to a dataset of hospital recordings.

Contact:

\nchristian.vergara@polimi.it

SEMINAR:

\nS. pagani\, MOX\, Dipartimento di Matematica\, Politecnico di Milano

Title:

\nA reduced-order strategy for efficient state/parameter
identification in cardiac electrophysiology

Abstract:

\nA re
duced basis (RB) ensemble Kalman Filter is proposed for the efficient solu
tion of Bayesian inverse problems\, namely state/parameter identification
and uncertainty quantification\, arising from cardiac electrophysiology. I
n particular\, starting from noisy boundary data\, we aim at identifying t
he position and the form of ischemic regions described through suitable pa
rametrized quantities or fields.

\nIn this context\, the forward prob
lem is typically modeled by a system of nonlinear unsteady PDEs\, e.g. the
monodomain or the bidomain equations for the propagation of the electric
potential in the cardiac muscle. The ensemble Kalman Filter (like other Ba
yesian filtering techniques) requires a huge amount of queries to the forw
ard problem\, thus entailing an often prohibitive computational cost. To s
peed up the solution of the inverse problem\, we exploit a reduced basis m
ethod to approximate the solution of the forward problem. In particular\,
we adopt a RB method relying on (i) proper orthogonal decomposition for th
e construction of RB spaces\, (ii) clustering techniques for the sake of s
election of local RB spaces and (iii) suitable hyper-reduction techniques\
, such as the discrete empirical interpolation method\, for the evaluation
of nonlinear terms.

\nA relevant question\, arising when a reduced-o
rder model (like the one built with the RB method) is exploited to solve i
nverse problems\, is related to the propagation along the filtering proces
s of reduction errors (i.e. the error between the full-order and the reduc
ed-order model). Indeed\, it is crucial to be able to quantify these latte
r in order to obtain an accurate solution to the inverse problem. As a con
sequence\, we consider a reduction error model based on kriging interpolat
ion in order to gauge the effect of the state reduction on the whole inver
sion procedure.

\nAs a proof of concept\, we present some numerical r
esults exploiting the proposed procedure when a monodomain model is used f
or the description of the electrical potential in presence of ischemic are
as\, described through some unknown or uncertain parameters/fields.

\nchristian.vergara@polimi.it\n END:VEVENT BEGIN:VEVENT UID:8g7hfm4clebhrbsej0l3a8g1ac@google.com DTSTAMP:20170923T233235Z CATEGORIES: CONTACT: DESCRIPTION:SEMINAR:\nBruno Guerciotti\, MOX – Dipartimento di Matematica\, Politecnico di Milano\nTitle:\nComputational study of the risk of resteno sis in coronary bypasses\nAbstract:\nCoronary artery disease\, which is on e of the leading causes of death in the world\, is caused by the build-up of atherosclerotic plaques in the vessel walls. The result is a reduction of oxygen supply to the heart\, which increases the risk of myocardial inf arction\, stroke and unstable angina. For high-risk patients\, coronary ar tery bypass graft (CABG) is the preferred treatment. In particular\, the g old standard procedure for the surgical treatment of the left anterior des cending (LAD) coronary artery disease is the left internal mammary\nartery (LIMA) bypass. However\, despite its excellent patency rates\, LIMA\nbypa ss may fail due to restenosis. Specifically\, the long-term patency of LIM A is thought to be related to the degree of stenosis in the native vessel. \nIn this context\, we present a computational study of the fluid-dynamics in patient-specific geometries with the aim of investigating a possible r elationship between coronary stenosis and LIMA graft failure. Firstly\, we propose a strategy to prescribe realistic boundary conditions in absence of measured data\, based on an extension of the well–known Murray’s law to provide the flow division at bifurcations in case of stenotic vessels and non-Newtonian blood rheology. With the aim of investigating the actual in fluence of non-Newtonian blood rheology on the hemodynamics of 3D patient- specific stenotic vessels\, we also show some results regarding the compar ison between Newtonian and non-Newtonian rheology. Then\, we show the resu lts regarding numerical simulations in patients treated with grafts in whi ch the degree of coronary stenosis is virtually varied\, in order to compa re the fluid-dynamics in terms of hemodynamic indices potentially involved in restenosis development. Finally\, we present some preliminary results concerning fluid-structure interaction simulations in CABGs with the aim o f better understanding the influence of the bypass mechanical properties o n the risk of graft failure.\nContact:\nchristian.vergara@polimi.it DTSTART;TZID=Europe/Rome:20160928T123000 DTEND;TZID=Europe/Rome:20160928T133000 LOCATION:Aula Saleri VI Piano Dipartimento di Matematica\, Politecnico di M ilano SEQUENCE:0 SUMMARY:Seminario biomox Guerciotti URL:https://bio.mox.polimi.it/event/seminario-biomox-guerciotti/ X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\n

SEMINAR:

\nBruno Guerciotti\, MOX – Dipartimento di Matematica\, Politecnico di Mi
lano

Title:

\nComputational study of the risk of restenosis i
n coronary bypasses

Abstract:

\nCoronary artery disease\, whi
ch is one of the leading causes of death in the world\, is caused by the b
uild-up of atherosclerotic plaques in the vessel walls. The result is a re
duction of oxygen supply to the heart\, which increases the risk of myocar
dial infarction\, stroke and unstable angina. For high-risk patients\, cor
onary artery bypass graft (CABG) is the preferred treatment. In particular
\, the gold standard procedure for the surgical treatment of the left ante
rior descending (LAD) coronary artery disease is the left internal mammary

\nartery (LIMA) bypass. However\, despite its excellent patency rate
s\, LIMA

\nbypass may fail due to restenosis. Specifically\, the long
-term patency of LIMA is thought to be related to the degree of stenosis i
n the native vessel.

\nIn this context\, we present a computational s
tudy of the fluid-dynamics in patient-specific geometries with the aim of
investigating a possible relationship between coronary stenosis and LIMA g
raft failure. Firstly\, we propose a strategy to prescribe realistic bound
ary conditions in absence of measured data\, based on an extension of the
well–known Murray’s law to provide the flow division at bifurcations in ca
se of stenotic vessels and non-Newtonian blood rheology. With the aim of i
nvestigating the actual influence of non-Newtonian blood rheology on the h
emodynamics of 3D patient-specific stenotic vessels\, we also show some re
sults regarding the comparison between Newtonian and non-Newtonian rheolog
y. Then\, we show the results regarding numerical simulations in patients
treated with grafts in which the degree of coronary stenosis is virtually
varied\, in order to compare the fluid-dynamics in terms of hemodynamic in
dices potentially involved in restenosis development. Finally\, we present
some preliminary results concerning fluid-structure interaction simulatio
ns in CABGs with the aim of better understanding the influence of the bypa
ss mechanical properties on the risk of graft failure.

Contact:

\nchristian.vergara@polimi.it

SEMINAR:

\nEnrico Facca\, Franco Cardin\, Mario Putti (Dipartimento di Matematica\
, Università di Padova)

Title:

\nBiologically inspired formul
ation of optimal transportation problems. An unexpected branching source\n

Abstract:

\nWe have recently developed an approach\, based on
an extension of a model proposed by Tero et al (2007) for the simulation o
f the dynamics of a slime mold (Physarium Polycephalum). We conjecture th
at this model is an original formulation of the PDE-based OT problem. This
new formulation assumes that the potential and the diffusion coefficient
(the latter yielding the transportation plan) are time dependent. The clas
sical constraint on the norm of the gradient is then replaced by an ODE de
scribing transient dynamics of the diffusion coefficient.

\nAnalytica
l results in the case of the Monge-Kantorovich problem\, although yet larg
ely incomplete\, suggest that indeed the conjecture is true. This is suppo
rted by several numerical experiments showing that at large times the solu
tion to this problem is equivalent to the solution of the classical Monge-
Kantorovich PDE based OT. One of the most important advantages of the prop
osed formulation is that its numerical solution is very efficient and well
-defined using simple numerical approaches. Moreover\, this dynamical exte
nsion allows the reconstruction of the time-history of the process\, thus
enlarging the applicability of the OT model to wider sets of processes. Th
e proposed model can also be easily adapted to branched and congested tran
sport problems. Preliminary numerical simulations show that the proposed f
ormulation is efficient in finding solutions also of congested transport a
nd branched transport problems.

\nWhile the interpretation via $p$-La
placians allows a straight forward interpretation of the new formulation i
n the simulation of congested transport\, only numerical evidence is curre
ntly available for applications to branched transport problems. Although
obvious limitations are present in the numerical solution of highly discon
tinuous problems\, we present some experimental convergence results showin
g robustness of the scheme for sufficiently regular solutions. Finally\, w
e will present models and related numerical results of diverse applicatio
ns of this formulation ranging from slime-mold dynamics to geomorphologica
l applications\, and discuss current and future progress.

Contact:

\nchristian.vergara@polimi.it

SEMINAR:

\nRiccardo Gottardi\, Center for Cellular and Molecular Engineering\, Uni
versity of Pittsburgh\, PA\, USA

Title:

\n3D microphysiologic
al systems: from modeling\, to drug discovery\, developmental biology\, an
d space research

Abstract:

\nA growing research in recent yea
rs focused on the development of next generation bioreactors capable of ge
nerating engineered constructs that mimic at least some of the physiologic
al functions of native organ systems. Such microphysiological systems rely
on the combination of microfluidic and tissue engineering to generate a h
igh number of identical 3D organoid models that can be used for drug and t
oxicological screening.

\nMoreover\, the ultimate aim is to be able t
o connect multiple tissues within an organ system and from there multiple
organ systems among themselves to better recapitulate the complexity and i
nterconnection of human physiology\, going from organ-on-a-chip to humans-
on-a-chip. The effective development of these devices requires a solid und
erstanding of their interconnected fluidics to predict the transport of nu
trients and waste through the constructs and improve the design accordingl
y. In this lecture\, the focus will be on a specific model of bioreactor d
eveloped at the Center for Cellular and Molecular Engineering (CCME)\, wit
h multiple input/outputs\, aimed at generating osteochondral constructs\,
i.e.\, a biphasic construct in which one side is cartilaginous in nature\,
while the other is osseous. Some of the challenges at the level of comput
ational modelling of the system will be described\, such as addressing the
multi-physics nature of the problem that combines free flow in cha!

\n nnels with hindered flow in porous media\, and coupling of fluid dynami
cs with advection-diffusion-reaction equations that model the transport of
biomolecules throughout the system and their interaction with living cons
tructs. The same design and modelling approach is applicable to multi-cham
ber\, interconnected system. In particular\, it may be applied to human-on
-chip devices. To this end\, a lumped parameter approach to predict the be
havior of multi-unit bioreactor systems with modest computational effort\,
will also be described. Furthermore\, the lecture will present a comparis
on of the modeling outcomes with the experimental results and will introdu
ce some of the opportunities opened by the possibility of using microphysi
ological systems to understand human physiology in challenging environment
s\, such as microgravity on board the International Space Station\, which
is the object of a recent grant obtained by CCME. Finally\, the lecture wi
ll outline some open problems where a !

\n modelling and computationa
l approach can help guide the experi!

\n mental development of microp
hysiological systems\, such as understanding the processes of limb morphog
enesis\, digit patterning\, and segmentation\, and their translation to a
regenerative approach.

SEMINAR:

\nLaura Sangalli (MOX)

Title:

\nPDE regularized principal co
mponent analysis on bidimensional manifolds\, with applications to neuroim
aging data

Abstract:

\nMotivated by the analysis of high-dime
nsional neuroimaging signals over the cerebral cortex\, we introduce a pri
ncipal component analysis technique that can be used for exploring the va
riability and performing dimensional reduction of signals observed over tw
o-dimensional manifolds. The proposed method is based on a PDE regularizat
ion approach\, involving the Laplace-Beltrami operator associated to the m
anifold domain. The model introduced can be applied to data observed over
any two-dimensional manifold topology\, and can naturally handle missing d
ata and signals evaluated in different grids of points. The proposed metho
d is applied to the analysis of resting state functional magnetic resonanc
e imaging data from the Human Connectome Project.

Contact:

\n
christian.vergara@polimi.it

SEMINAR:

\nJ. F. Rodriguez\, Chemistry\, Materials\, and Chemical Engineering Depa
rtment “Giulio Natta”\, Politecnico di Milano

Title:

\nModeli
ng Inelastic Effects in Reconstituted Crosslinked F-Actin Networks

Abstract:

\nThe interplay between the conventional cross-linked acti
n filaments by means of actin-binding proteins\, and physical bundling\, b
y means of spatial organization of nucleating factors can be an alternativ
e to understand several inelastic effects that take place in the cytoskele
ton. In this regard\, in vitro actin networks without active molecular mot
ors have been considered to be in thermodynamic equilibrium[1]. However\,
recent experiments performed by Schmoller et

\nal. [5] in artificiall
y reconstructed crosslinked actin networks have shown this networks to be
non-equilibrium networks. In their experiments they have observed that\, t
he internal stress trapped during network formation gives this material a
unique behavior. Differently to most soft materials\, such as rubber and l
iving soft tissues\, where nonlinear deformations irreversibly alter the m
echanical properties of the material by causing a pronounced softening whe
n cyclically deformed\, reconstituted crosslinked actin networks show soft
ening and hardening effects

\nwhen the network is subject to cyclic s
hear strain. As a continuation of a previous work [2]\, here we propose a
constitutive model within the framework of continuum mechanics for the ine
lastic stress-strain behavior of reconstituted crosslinked actin networks.
The network will be described using an homogenized framework based on the
eight chain model [3]. A dynamic model for the crosslinks is introduced i
n order to account for the inelastic response

\nof the network. In th
is regard\, we assume that crosslinks can be disrupted in either a reversi
ble or irreversible manner. Reversible disruption of a crosslink is modele
d as a two state process [4] in which the transition rates are modulated b
y the out of equilibrium forces. On the contrary\, irreversible crosslink
disruption will be modeled as a Bell-like bond rupture. These effects are
introduced in the model by considering the bundle contour length\, Lc as a
n

\nstochastic variable dependent on the reversible and irreversible
dynamics of the crosslink.

Contact:

\nchristian.vergara@polim
i.it

SEMINAR:

\nDaniele Bissacco\, Scuola di Specializzazione in Chirurgia Vascolare\,
Università degli Studi di Milano

Title:

\nAneurisma dell’aor
ta addominale: dalla clinica alla bioingegneria. Il punto di vista medico<
/p>\n

Abstract:

\nL’Aneurisma dell’Aorta Addominale (AAA) è definit
o come una dilatazione patologica del vaso arterioso che assicura l’apport
o sanguigno al distretto addominale e degli arti inferiori. Circa il 7% de
lla popolazione sopra i 70 anni è affetta da AAA\, che in caso di rottura\
, possiede una mortalità superiore all’80%. L’eziopatogenesi e la storia n
aturale non sono ancora state chiarite\, sebbene basi emodinamiche\, bioch
imiche e ambientali siano coinvolte nella formazione e progressione della
sacca aneurismatica. La terapia endovascolare (EVAR)\, mediante l’utilizzo
di endoprotesi posizionate e rilasciate da accessi femorali è al momento
la soluzione gravata da un minor tasso di complicanze immediate rispetto a
lla terapia chirurgica open\, sebbene una attenta sorveglianza dell’impian
to protesico debba essere proseguita anche anni dopo l’intervento.

\n
Il seminario si propone di descrivere le basi cliniche\, le cause e i fatt
ori di rischio per la comparsa di AAA\, le opzioni terapeutiche utilizzate
e le complicanze correlate all’intervento. Particolare interesse verrà da
to ai campi di ricerca clinica e bioingegneristica futuri\, per stimolare
la cooperazione tra figure professionali sempre più reciprocamente utili n
el capo della ricerca medica.

Contact:

\nchristian.vergara@po
limi.it