Mechano-Chemical organisation in single cells.We have an open PhD position to study the mechano-chemical organisation of cells from a physical and mathematical point of view. Individually or collectively, cells move due to mechanical and chemical gradients and doing so they self-organise in very specific forms. Understanding the physical laws under mechano-chemical gradients can head to establish new protocols in the control of cell structures. The final goal of the project is to manipulate cells so that the morphology of cell structures can be predicted, e.g. in biological-based prosthesis.
The eventual candidate will work in a newly established and young research group in the field of mechanobiology under the supervision of Dr. Pablo Saez (http://www-lacan.upc.es/saez/), at the Universitat Politècnica de Catalunya. The lab is part of a broader group with focus on numerical methods in engineering (http://www-lacan.upc.es/). The candidate will also collaborate with Prof. Marino Arroyo (http://www-lacan.upc.es/arroyo/) with a broad expertise in numerical methods and cell mechanics. The project is related to a recently granted European Research Project on the mechanobiology of cells at different scales.
The eventual student will work at different scales of the problem. Depending on the candidate’s background the work will be more related to theoretical or numerical developments required to accomplish the project. Therefore, we are looking for students with a wide background of knowledge, with a bachelor degree in mechanical engineering, physics or applied mathematics. The candidate should be a highly dynamic and eager student looking forward expand his/her current knowledge on the field of cell mechanobiology. Biological background is not necessary. The candidate is expected to have a high profiency of the English language, both written and spoken.Interested candidates should send a motivation letter and the CV along with the academic transcript to pablo.saez@upc.edu. We aim to start the project after the summer of 2017 at the latest. We encourage any interested candidate to send his/her application as soon as possible.
1) FINITE-ELEMENT MODELING AND PATIENT-SPECIFIC PREDICTION OF ANEURYSM GROWTH AND RUPTURE IN THE ASCENDING THORACIC AORTA
Keywords: Finite-element method, nonlinear mechanics, mechanobiology, aortic aneurysm, extracellular matrix degeneration, nonlocal mechanics, fluid-structure interactions.
Academic context: This PhD thesis is part of the interdisciplinary Biolochanics – Localization in biomechanics and mechanobiology of aneurysms: Towards personalized medicine – project (2015-2020) awarded to Stéphane Avril (http://www.mines-stetienne.fr/stephane-avril) under the European Research Council Consolidator Grant scheme (http://erc.europa.eu/consolidator-grants). His group at Mines Saint-Etienne leads major international research projects in the domain of soft tissue biomechanics, focused especially on aortic aneurysm through a longstanding collaboration with the Saint-Etienne University Hospital. The Biolochanics project also relies on collaborations with Yale University (USA).
Scientific context: The growth of aortic aneurysms is associated with several mechano-chemo-biological interactions leading to modifications of the tissue structure including the fragmentation of elastin and changes in the amount and organization of collagen. We have modeled these mechanisms in a constitutive model based on the constrained mixture approach, where each constituent has an elastic constitutive response governed by an anisotropic strain energy function and an inelastic constitutive response governed first by a scalar [1–d]-type damage formulation and second by a permanent deformation gradient related to the growth. The model is implemented as a user material in the Abaqus software.
Project summary: In this thesis, we will first start by performing different sensitivity studies on the numerical model, permitting to calibrate different parameters, including the different degradation rates of collagen and elastin and the related time evolution of stress and strain distribution. Calibration will be performed against experimental data acquired by another person working on the project. After this stage we will apply the model to simulate the growth of ATAA in patients for whom we have reconstructed the aortic geometry for several years (on going longitudinal study at the university hospital of Saint-Etienne). In addition to the geometry, we have also access to hemodynamics through 4D MRI also acquired longitudinally for these patients, and even stiffness of the wall through an inverse method developed by another student working also on the project. All these data will be used to calibrate the finite-element model on a cohort of +20 patients in order to better understand how aneurysms grow and how the damage localizes in the tissue. The final goal will be to simulate numerically the scenario of growth and possible rupture for any patient’s aneurysm, just from the 4D MRI data, thus aiding the surgeon to take important decision such as surgical repair.
Candidate profile: Candidates with strong backgrounds in engineering mechanics, biophysics, biomechanics, and/or applied mathematics are expected. Background in finite elements and nonlinear mechanics will be highly appreciated. Motivation for ground-breaking experimental work and interest in mechanobiology are recommended.
Administrative aspects: Situated in the dynamic Rhône-Alpes region (Lyon – France) in the heart of the European Union, Mines-Saint-Etienne is one of the oldest and most prestigious Grandes Ecoles, and has, since 1816, lived up to its motto “innovante par tradition – inspiring innovation“. Working in a culturally and scientifically most stimulating atmosphere, the successful candidate will earn
internationally competitive salaries. Employment durations is 3 years. The employer is Armines, linked by state-approved agreements to Mines Saint-Etienne. The thesis will start in October 2017.
If you are interested, send a curriculum vitae, a cover letter describing previous research experience and interests, the names and contact information of two references. Please, submit via email with “ERC Biolochanics D3” on the subject line to Prof Stéphane AVRIL, PhD (avril@emse.fr). Deadline for applications: 30th April 2017.
2) MULTISCALE CHARACTERIZATION OF PROTEOLYTIC REMODELING AND OF ITS BIOMECHANICAL EFFECTS IN THE AORTIC WALL
Keywords: Mechanobiology, aortic aneurysm, extracellular matrix degeneration, biomechanical tests, full-field measurements, digital image correlation, OCT, collagenase
Academic context: This PhD thesis is part of the interdisciplinary Biolochanics – Localization in biomechanics and mechanobiology of aneurysms: Towards personalized medicine – project (2015-2020) awarded to Stéphane Avril (http://www.mines-stetienne.fr/stephane-avril) under the European Research Council Consolidator Grant scheme (http://erc.europa.eu/consolidator-grants). His group at Mines Saint-Etienne leads major international research projects in the domain of soft tissue biomechanics, focused especially on aortic aneurysm through a longstanding collaboration with the Saint-Etienne University Hospital. The Biolochanics project also relies on collaborations with Yale University (USA).
Scientific context: The growth of aortic aneurysms is associated with several morphological abnormalities, particularly in the media. Two abnormalities standout from a mechanical standpoint: the fragmentation of elastin and changes in the amount and organization of collagen. Changes in the organization of these two load-bearing components signal that more than likely significant changes in the mechanical properties are occurring.
Project summary: In this project, we will focus on the contribution of collagen, as the fragmentation of elastin has been implicated in the normal aging process. In aneurysms the normal production and degradation rates of collagen are disturbed leading to enlargement and local weakening of the aortic wall. To investigate this localized weakening of the tissue through degradation of its collagen fibers we will develop a novel biochemically-based method to locally degrade the collagen fibers and characterize its biomechanical effects.
Sample will be cut from aortic tissue and tested in an inflation device. Using a digital image correlation system at the macro scale (developed by a post-doc also working on the project) and an optical coherence tomography (OCT) system at the micro scale (developed by another post-doc), images will be recorded during the inflation. While the pressure is held constant, a fine tipped syringe will be used to apply purified collagenase in buffered saline to a small region of the sample. After the application of collagenase the sample and testing device will be placed in a saline bath for incubation. The selected incubation times are short to ensure that the collagen fibers are only partially degraded. To verify that the enzymatic digestion of collagen occurred we will examine histological images. After the treatment, we will inflate the tissue to failure. We will subject a total of 30 ATAA wall specimens to this protocol.
The stress and strain fields at each pressure stage will be calculated using an inverse method based on the data of the digital image correlation system at the macro scale and of the optical coherence tomography system. The focus will be on determining if any novel local features are identified in the collagenase treated region, particularly at physiologic pressure. We will use the calculated mechanical properties to confirm that the collagenase treatment had the intended effect of weakening the mechanical properties at the application site. The experimental method is fully capable of capturing these local changes in material properties. By comparing the range of rupture stress, we will determine how localized collagen degradation impacts the final rupture stress.
Candidate profile: Candidates with strong backgrounds in engineering mechanics, biophysics, biomechanics, and/or applied mathematics are expected. Background in experimental mechanics
and optical measurement techniques will be appreciated. Motivation for ground-breaking experimental work and interest in mechanobiology are recommended.
Administrative aspects: Situated in the dynamic Rhône-Alpes region (Lyon – France) in the heart of the European Union, Mines-Saint-Etienne is one of the oldest and most prestigious Grandes Ecoles, and has, since 1816, lived up to its motto “innovante par tradition – inspiring innovation“. Working in a culturally and scientifically most stimulating atmosphere, the successful candidate will earn internationally competitive salaries. Employment durations is 3 years. The employer is Armines, linked by state-approved agreements to Mines Saint-Etienne. The thesis will start in October 2017.
If you are interested, send a curriculum vitae, a cover letter describing previous research experience and interests, the names and contact information of two references. Please, submit via email with “ERC Biolochanics D2” on the subject line to Prof Stéphane AVRIL, PhD (avril@emse.fr). Deadline for applications: 30th April 2017.
Description: The Institute of Lightweight Design and Structural Biomechanics of TU Wien invites applications for the permanent position of a Senior Scientist in the research group for Biomechanics. One of the main tasks of this post will be acting as a laboratory manager for the Interfacultary Laboratory for Micro- and Nanomechanics of Biological and Biomimetical Materials (www.mmlab.tuwien.ac.at).
Qualifications: We are looking for a scientist with a completed Ph.D. in Mechanical Engineering, Material Science, Biomedical Engineering or Physics who has
Further information: For informal discussions please contact Professor Philipp Thurner, pthurner@ilsb.tuwien.ac.at
How to apply: please send applications to rene.fuchs@tuwien.ac.at no later than February 8th 2017
by Bert van Rietbergen
Steve Cowin passed away October 19 last year. Several generations of ESB members have been raised with his pioneering theories of bone adaptation and bone structure-properties relationships, and it feels like a great loss his contribution to this field now is closed. Rather than writing a full obituary, which can be found elsewhere (http://www.cism.it/about/newsletters/), I wanted to focus this writing on why he was so important for many of the ESB members, and for me in particular.
The ESB is inviting proposals for the organization of its annual congress in July 2020. If you are interested in hosting and organizing ESB2020, please read the ESB 2020 Bid rules for details.
Bids should be sent to prof. Harry van Lenthe (harry.vanlenthe@kuleuven.be), Chair of the Meetings Committee. He can also be contacted for further information.
The deadline for submitting your bid for ESB2020 is 31st March 2017.
Assessing the impact of hydrodynamic loads on shoulder joint injuries in swimming
Closing Date: Monday 13 February 2017
Increasing activity and fitness levels across the general population is key to combatting the challenges associated with obesity and an ageing population. Swimming is considered to be beneficial as it offers a non weight-bearing, full-body form of cardiovascular exercise. These benefits might be offset, however, by an increased risk of shoulder injury, a common occurrence within the sport.
This project aims to investigate the mechanisms of shoulder injury through understanding how the hydrodynamic forces acting on a swimmer’s arm are supported by the musculoskeletal structure.
This project is fundamentally interdisciplinary requiring in-depth analysis of both complex fluid dynamics, biomechanics and intricate musculoskeletal systems within the body. The mechanisms of shoulder injury can be investigated through the use of a musculoskeletal model to simulate muscle response and joint loadings in different conditions. However this approach requires accurate stroke kinematics and hydrodynamic forces both of which are extremely challenging to measure in aquatic sports such as swimming.
The study will involve acquiring detailed kinematics of the swimming stroke and the use of advanced Computational Fluid Dynamics to simulate the pressure distribution over the arm. Different optical techniques will be utilised to assess the soft tissue deformations caused by fluid loading and muscle contraction during various tasks. Ultimately this information will be used to predict internal forces in the upper limb during swimming and elucidate on possible mechanisms of shoulder injury.
We are looking for applicants with a strong background in engineering, mathematics or physics, with an interest in sports and biomechanics. A fully funded 3 year studentship is available for UK/EU students, with the stipend at the standard RCUK rate (currently £14500 tax free).
Due to the interdisciplinary nature of this project supervision will be split between the Faculties of Engineering and the Environment and Health Sciences. This project is also supported by both British Swimming and the English Institute of Sport providing a wealth of expertise, support and access to world class biomechanists and coaches. This research will build on the previous experience and success of Southampton’s Performance Sport Engineering Lab and their support of British swimming in both the London and Rio Olympic games.
If you wish to discuss any details of the project informally, please contact Joseph Banks, Fluid Structure Interaction research group, Email: J.Banks@soton.ac.uk, Tel: +44 (0) 2380 59 6625.
Reference: 825117AT
Project Reference: CMEES-FSI-134
Read the advert and apply online here
Project Details: Age-delaying interventions are currently tested on animal models such as UM-HET3 mice. Among them, calorie restriction (CR) was found to increase the life-spam in mice models and has the potential of delay age-related pathologies. However, the effect of CR on the musculoskeletal health is still debated and becomes fundamental when studying its effect on musculoskeletal pathologies such as osteoarthritis (OA) and osteoporosis (OP).
The hypothesis of this study is that CR improves musculoskeletal health in old UM-HEY3 mice. In this project the student will characterise the properties of the knee joints and o whole tibiae of UM-HET3 mice in order to study the effect of CR on the properties of cartilage and bone and its relationship with gender and age. Tissues from female and male mice at three different ages (8, 12 and 22 months) have been already collected by our collaborators and will be analysed in Sheffield. The student will be taught how to perform state of the art assessments of OA and OP by combining micro-computed tomography (microCT) imaging, image processing and computational modelling. MicroCT allows us to acquire 3-dimensional high-resolution images of the whole bone and joint and to analyse in details their morphological and densitometric properties. Furthermore, microCT-based finite element (FE) models developed in Dall’Ara’s group are engineering methods that can provide a non-invasive assessment of bone mechanical properties from the acquired images. The assessment of degree of OA, bone morphometric parameters, distribution of bone mineral density within the tibia and bone strength will be provide a unique database for the characterisation of the effect of CR on bone and cartilage.
Entry Requirements
Candidates must have a first or upper second class honors degree or significant research experience. Strong imaging and/or computational background is required; experience with microCT image processing will be advantageous.
Funding
The Faculty of Medicine, Dentistry & Health Doctoral Academy Scholarships cover Home/EU fee and RCUK rate stipend for three years. Overseas students may apply but will need to fund the difference between the Home and Overseas fee from another source.
How to apply
Please apply through our online postgraduate application system including the Scholarship Application section where you need to tick the ‘University Scholarships’ box. The form will ask you to summarise your research proposal in less than 800 words. If you are unsure about what to put in this section, please contact your prospective supervisor. Please name your supervisor and select their department Oncology and Metabolism through the online form.
Deadline: 5pm 1st February 2017
Supervisors: Dr Enrico Dall’Ara, Department of Oncology and Metabolism and INSIGNEO institute for in silico medicine and Dr Ilaria Bellantuono, Department of Oncology and Metabolism.
Enquiries:
Interested candidates should in the first instance contact Dr Dall’Ara e.dallara@sheffield.ac.uk
Corporate members of the ESB:
