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Chloé Chamard,1,2 Jerome J Maller,3,4 Nicolas Menjot,5 Eloi Debourdeau,1 Virginie Nael,6 Karen Ritchie,2,7 Isabelle Carriere,2,* Vincent Daien1,2,8,* 1Department of Ophthalmology, Gui de Chauliac Hospital, Montpellier, F-34000, France; 2Institute for Neurosciences of Montpellier INM, University Montpellier, INSERM, Montpellier, F-34091, France; 3General Electric Healthcare, Melbourne, VIC, Australia; 4Monash Alfred Psychiatry Research Centre, Melbourne, VIC, Australia; 5Department of Neuroradiology, Gui de Chauliac Hospital, Montpellier, F-34000, France; 6Bordeaux Population Health Research Center, UMR 1219, University Bordeaux, INSERM, Bordeaux, F-33000, France; 7Department of Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK; 8The Save Sight Institute, Sydney Medical School, the University of Sydney, Sydney, NSW, Australia*These authors contributed equally to this workCorrespondence: Chloé Chamard, Department of Ophthalmology, Gui de Chauliac Hospital, 80 avenue Augustin Fliche, Montpellier, F-34000, France, Tel +33 6 33 55 65 06, Email chloe.chamard@gmail.comPurpose: Visual impairment is a major cause of disability and impairment of cognitive function in older people. Brain structural changes associated with visual function impairment are not well understood. The objective of this study was to assess the association between visual function and cortical thickness in older adults.Methods: Participants were selected from the French population-based ESPRIT cohort of 2259 community-dwelling adults ≥ 65 years old enrolled between 1999 and 2001. We considered visual function and brain MRI images at the 12-year follow-up in participants who were right-handed and free of dementia and/or stroke, randomly selected from the whole cohort. High-resolution structural T1-weighted brain scans acquired with a 3-Tesla scanner. Regional reconstruction and segmentation involved using the FreeSurfer image-analysis suite.Results: A total of 215 participants were included (mean [SD] age 81.8 [3.7] years; 53.0% women): 30 (14.0%) had central vision loss and 185 (86.0%) normal central vision. Vision loss was associated with thinner cortical thickness in the right insula (within the lateral sulcus of the brain) as compared with the control group (mean thickness 2.38 [0.04] vs 2.50 [0.03] mm, 4.8% thinning, pcorrected= 0.04) after adjustment for age, sex, lifetime depression and cardiovascular disease.Conclusion: The present study describes a significant thinning of the right insular cortex in older adults with vision loss. The insula subserves a wide variety of functions in humans ranging from sensory and affective processing to high-level cognitive processing. Reduced insula thickness associated with vision loss may increase cognitive burden in the ageing brain.Keywords: visual function, vision, cortical thickness, brain, morphometry, MRI

International audience; Background: Glucometabolic changes, such as high glycemic load (GL) diet and insulin resistance (IR), are potential risk factor of Alzheimer's disease (AD). Yet, the effect of these factors on brain alterations that contribute to AD pathology has not been clearly demonstrated.Objective: We aimed to assess the relationship of GL and IR with gray matter volumes involved in prodromal dementia.Methods: GL and Triglyceride-Glucose (TyG) index, an IR surrogate marker, were calculated in 497 participants who underwent magnetic resonance imaging (MRI). The gray matter volumes most related to prodromal dementia/mild cognitive impairment (diagnosed in 18/158 participants during the 7-year follow-up) were identified using a data-driven machine learning algorithm.Results: Higher GL diet was associated with reduced amygdala volume. The TyG index was negatively associated with the hippocampus, amygdala, and putamen volumes.Conclusion: These results suggest that GL and IR are associated with lower gray matter volumes in brain regions involved in AD pathology.

Funding Information: This work was conducted in part using the resources of the Advanced Computing Center for Research and Education at Vanderbilt University, Nashville, TN. KS, BL, CH were supported by the National Institutes of Health under award numbers R01EB017230, and T32EB001628, and in part by ViSE/VICTR VR3029 and the National Center for Research Resources, Grant UL1 RR024975-01. This work was also possible thanks to the support of the Institutional Research Chair in NeuroInformatics of Université de Sherbrooke, NSERC and Compute Canada (MD, FR). MP received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 754462. The Wisconsin group acknowledges the support from a core grant to the Waisman Center from the National Institute of Child Health and Human Development (IDDRC U54 HD090256). NSF OAC-1916518, NSF IIS-1912270, NSF IIS-1636893, NSF BCS-1734853, NIH NIBIB 1R01EB029272-01, and a Microsoft Faculty Fellowship to F.P. LF acknowledges the support of the Cluster of Excellence Matters of Activity. Image Space Material funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany´s Excellence Strategy – EXC 2025. SW is supported by a Medical Research Council PhD Studentship UK [MR/N013913/1]. The Nottingham group's processing was performed using the University of Nottingham's Augusta HPC service and the Precision Imaging Beacon Cluster. JPA, MA and SMS acknowledges the support of FCT - Fundação para a Ciência e a Tecnologia within CINTESIS, R&D Unit (reference UID/IC/4255/2013). MM was funded by the Wellcome Trust through a Sir Henry Wellcome Postdoctoral Fellowship [213722/Z/18/Z]. EJC-R is supported by the Swiss National Science Foundation (SNSF, Ambizione grant PZ00P2 185814/1). CMWT is supported by a Sir Henry Wellcome Fellowship (215944/Z/19/Z) and a Veni grant from the Dutch Research Council (NWO) (17331). FC acknowledges the support of the National Health and Medical Research Council ofAustralia (APP1091593 and APP1117724) and the Australian Research Council (DP170101815). NSF OAC-1916518, NSF IIS-1912270, NSF IIS-1636893, NSF BCS-1734853, Microsoft Faculty Fellowship to F.P. D.B. was partially supported by NIH NIMH T32-MH103213 to William Hetrick (Indiana University). CL is partly supported by NIH grants P41 EB027061 and P30 NS076408 “Institutional Center Cores for Advanced Neuroimaging. JYMY received positional funding from the Royal Children's Hospital Foundation (RCH 1000). JYMY, JC, and CEK acknowledge the support of the Royal Children's Hospital Foundation, Murdoch Children's Research Institute, The University of Melbourne Department of Paediatrics, and the Victorian Government's Operational Infrastructure Support Program. C-HY is grateful to the Ministry of Science and Technology of Taiwan (MOST 109-2222-E-182-001-MY3) for the support. LC acknowledges support from CONACYT and UNAM. ARM acknowledges support from CONACYT. LJO, YR, and FZ were supported by NIH P41EB015902 and R01MH119222. AJG was supported by P41EB015898. NM was supported by R01MH119222, K24MH116366, and R01MH111917. This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme under Grant Agreement No. 785907 & 945539 (HBP SGA2 & SGA3), and from the ANR IFOPASUBA- 19-CE45-0022-01. PG, CR, NL and AV were partially supported by ANID-Basal FB0008 and ANID-FONDECYT 1190701 grants. We would like to acknowledge John C Gore, Hiromasa Takemura, Anastasia Yendiki, and Riccardo Galbusera for their helplful suggestions regarding the analysis, figures, and discussions. Funding Information: This work was conducted in part using the resources of the Advanced Computing Center for Research and Education at Vanderbilt University, Nashville, TN. KS, BL, CH were supported by the National Institutes of Health under award numbers R01EB017230, and T32EB001628, and in part by ViSE/VICTR VR3029 and the National Center for Research Resources, Grant UL1 RR024975-01. This work was also possible thanks to the support of the Institutional Research Chair in NeuroInformatics of Universit? de Sherbrooke, NSERC and Compute Canada (MD, FR). MP received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sk?odowska-Curie grant agreement No 754462. The Wisconsin group acknowledges the support from a core grant to the Waisman Center from the National Institute of Child Health and Human Development (IDDRC U54 HD090256). NSF OAC-1916518, NSF IIS-1912270, NSF IIS-1636893, NSF BCS-1734853, NIH NIBIB 1R01EB029272-01, and a Microsoft Faculty Fellowship to F.P. LF acknowledges the support of the Cluster of Excellence Matters of Activity. Image Space Material funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany?s Excellence Strategy ? EXC 2025. SW is supported by a Medical Research Council PhD Studentship UK [MR/N013913/1]. The Nottingham group's processing was performed using the University of Nottingham's Augusta HPC service and the Precision Imaging Beacon Cluster. JPA, MA and SMS acknowledges the support of FCT - Funda??o para a Ci?ncia e a Tecnologia within CINTESIS, R&D Unit (reference UID/IC/4255/2013). MM was funded by the Wellcome Trust through a Sir Henry Wellcome Postdoctoral Fellowship [213722/Z/18/Z]. EJC-R is supported by the Swiss National Science Foundation (SNSF, Ambizione grant PZ00P2 185814/1). CMWT is supported by a Sir Henry Wellcome Fellowship (215944/Z/19/Z) and a Veni grant from the Dutch Research Council (NWO) (17331). FC acknowledges the support of the National Health and Medical Research Council of Australia (APP1091593 and APP1117724) and the Australian Research Council (DP170101815). NSF OAC-1916518, NSF IIS-1912270, NSF IIS-1636893, NSF BCS-1734853, Microsoft Faculty Fellowship to F.P. D.B. was partially supported by NIH NIMH T32-MH103213 to William Hetrick (Indiana University). CL is partly supported by NIH grants P41 EB027061 and P30 NS076408 ?Institutional Center Cores for Advanced Neuroimaging. JYMY received positional funding from the Royal Children's Hospital Foundation (RCH 1000). JYMY, JC, and CEK acknowledge the support of the Royal Children's Hospital Foundation, Murdoch Children's Research Institute, The University of Melbourne Department of Paediatrics, and the Victorian Government's Operational Infrastructure Support Program. C-HY is grateful to the Ministry of Science and Technology of Taiwan (MOST 109-2222-E-182-001-MY3) for the support. LC acknowledges support from CONACYT and UNAM. ARM acknowledges support from CONACYT. LJO, YR, and FZ were supported by NIH P41EB015902 and R01MH119222. AJG was supported by P41EB015898. NM was supported by R01MH119222, K24MH116366, and R01MH111917. This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme under Grant Agreement No. 785907 & 945539 (HBP SGA2 & SGA3), and from the ANR IFOPASUBA- 19-CE45-0022-01. PG, CR, NL and AV were partially supported by ANID-Basal FB0008 and ANID-FONDECYT 1190701 grants. We would like to acknowledge John C Gore, Hiromasa Takemura, Anastasia Yendiki, and Riccardo Galbusera for their helplful suggestions regarding the analysis, figures, and discussions. Publisher Copyright: © 2021 White matter bundle segmentation using diffusion MRI fiber tractography has become the method of choice to identify white matter fiber pathways in vivo in human brains. However, like other analyses of complex data, there is considerable variability in segmentation protocols and techniques. This can result in different reconstructions of the same intended white matter pathways, which directly affects tractography results, quantification, and interpretation. In this study, we aim to evaluate and quantify the variability that arises from different protocols for bundle segmentation. Through an open call to users of fiber tractography, including anatomists, clinicians, and algorithm developers, 42 independent teams were given processed sets of human whole-brain streamlines and asked to segment 14 white matter fascicles on six subjects. In total, we received 57 different bundle segmentation protocols, which enabled detailed volume-based and streamline-based analyses of agreement and disagreement among protocols foreach fiber pathway. Results show that even when given the exact same sets of underlying streamlines, the variability across protocols for bundle segmentation is greater than all other sources of variability in the virtual dissection process, including variability within protocols and variability across subjects. In order to foster the use of tractography bundle dissection in routine clinical settings, and as a fundamental analytical tool, future endeavors must aim to resolve and reduce this heterogeneity. Although external validation is needed to verify the anatomical accuracy of bundle dissections, reducing heterogeneity is a step towards reproducible research and may be achieved through the use of standard nomenclature and definitions of white matter bundles and well-chosen constraints and decisions in the dissection process.

For the clinical delivery of immunotherapies it is anticipated that cells will be cryopreserved and shipped to the patient where they will be thawed and administered. An established view in cellular cryopreservation is that following freezing, cells must be warmed rapidly (≤5 minutes) in order to maintain high viability. In this study we examine the interaction between the rate of cooling and rate of warming on the viability, and function of T cells formulated in a conventional DMSO based cryoprotectant and processed in conventional cryovials. The data obtained show that provided the cooling rate is −1 °C min−1 or slower, there is effectively no impact of warming rate on viable cell number within the range of warming rates examined (1.6 °C min−1 to 113 °C min−1). It is only following a rapid rate of cooling (−10 °C min−1) that a reduction in viable cell number is observed following slow rates of warming (1.6 °C min−1 and 6.2 °C min−1), but not rapid rates of warming (113 °C min−1 and 45 °C min−1). Cryomicroscopy studies revealed that this loss of viability is correlated with changes in the ice crystal structure during warming. At high cooling rates (−10 °C min−1) the ice structure appeared highly amorphous, and when subsequently thawed at slow rates (6.2 °C min−1 and below) ice recrystallization was observed during thaw suggesting mechanical disruption of the frozen cells. This data provides a fascinating insight into the crystal structure dependent behaviour during phase change of frozen cell therapies and its effect on live cell suspensions. Furthermore, it provides an operating envelope for the cryopreservation of T cells as an emerging industry defines formulation volumes and cryocontainers for immunotherapy products.

With the objective of improving MR endoluminal imaging of the colonic wall, electromagnetic simulations of different configurations of single-layer and double-layer, and double-turn endoluminal coil geometries were run. Indeed, during colon navigation, variations in coil orientation with respect to B0 are bound to occur, leading to impaired image acquisition due to a loss of signal uniformity. In this work, three typical coil orientations encountered during navigation were chosen and the resulting signal uniformity of the different geometries was investigated through the simulatedB1x,y/IRtvalues. Sampling this quantity over a circle of radius r enabled us to calculate the coefficient of variation (= standard deviation/mean) for this given distance. This procedure was repeated forr∈5;15 mm, which represents the region of interest in the colon. Our results show that single-loop and double-layer geometries could provide complementary solutions for improved signal uniformity. Finally, using four microelectromechanical system switches, we proposed the design of a reconfigurable endoluminal coil able to switch between those two geometries while also ensuring the active decoupling of the endoluminal coil during the RF transmission of an MR experiment.

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PURPOSE To demonstrate the feasibility of integrating the magnetization transfer (MT) preparations required for inhomogeneous MT (ihMT) within an MPRAGE-style acquisition. Such a sequence allows for reduced power deposition and easy inclusion of other modules. METHODS An ihMT MPRAGE-style sequence (ihMTRAGE) was initially simulated to investigate acquisition of the 3D ihMT data sequentially, or in an interleaved manner. The ihMTRAGE sequence was implemented on a 3T clinical scanner to acquire ihMT data from the brain and spine. RESULTS Both simulations and in vivo data provided an ihMT signal that was significantly greater using a sequential ihMTRAGE acquisition, compared with an interleaved implementation. Comparison with a steady-state ihMT acquisition (defined as having one MT RF pulse between successive acquisition modules) demonstrated how ihMTRAGE allows for a reduction in average power deposition, or greater ihMT signal at equal average power deposition. Inclusion of a prospective motion-correction module did not significantly affect the ihMT signal obtained from regions of interest in the brain. The ihMTRAGE acquisition allowed combination with a spatial saturation module to reduce phase wrap artifacts in a cervical spinal cord acquisition. CONCLUSIONS Use of preparations necessary for ihMT experiments within an MPRAGE-style sequence provides a useful alternative for acquiring 3D ihMT data. Compared with our steady-state implementation, ihMTRAGE provided reduced power deposition, while allowing use of the maximum intensity from off-resonance RF pulses. The 3D ihMTRAGE acquisition allowed combination of other modules with the preparation necessary for ihMT experiments, specifically motion compensation and spatial saturation modules.

International audience; The paper presents a new methodology for the numerical estimation of the Green's functions in complex external aeroacoustic configurations. Computational aeroacoustics is used to propagate multi-frequency signals from focus points to microphones. The method takes advantage of the sparsity of the Green's functions in the time-domain to minimize the simulation time. It leads to a complex sparse linear regression problem. To solve it, the Orthogonal Matching Pursuit algorithm is adapted. The method is first applied on the case of the diffraction by a rigid sphere. Results are studied both in terms of Green's function estimation and aeroacoustic beamforming. They show that the Green's functions are obtained with a good accuracy and enable to localize acoustic sources placed behind the diffracting object. The methodology is then applied on a NACA0012 2D wing in a potential flow for which the Green's function is not known analytically. The use of the reverse-flow reciprocity principle enables to reduce the complexity of the estimation problem when there are more scan points than microphones. It is shown that it is possible to take advantage of the presence of diffracting objects to improve the capability of detection of a sensor array.

International audience; Purpose - The area of left ventricular (LV) pressure-strain loop (PSL) is used as an index of regional myocardial work. The purpose of the present work is to compare the main segmental PSL markers and the derived global work indices, when they are calculated using an estimated pressure signal or an observed pressure signal.Methods and results - In nine patients implanted with a bi-ventricular pace-maker (CRT), LV pressure was invasively measured in five conditions: CRT-off, LV-pacing, right ventricular-pacing and two different CRT-pacing. For each condition, systolic blood pressure was measured by brachial artery cuff-pressure and transthoracic echocardiography loops were recorded simultaneously. The error and relative root mean square error (rRMSE) between measured and estimated pressure were calculated for each patient and each configuration. Correlation coefficient (R2) and Bland-Altman (BA) analysis were performed for PSL area and work indices. A total of 43 different haemodynamic conditions were compared (774 segmental PSL). The global rRMSE between estimated and measured LV-pressure was 12.3 mmHg. The estimated and measured segmental LV-PSL were strongly correlated, with an R2 of 0.98. BA analysis shows that the mean bias for the estimation of segmental LV-PSL area is 86.0 mmHg.%. A significant bias effect with linearly increasing error with pressure values is observed. R2 ≥ 0.88 and a mean bias in BA analysis ≤41.4 mmHg.% was observed for the estimation of global myocardial work indices.Conclusion - The non-invasive estimation for LV pressure-strain loop area and the global myocardial work indices obtained from LV-PSL strongly correlates with invasive measurements.

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement N° 777657; The critical thermal range for controlled rate cooling for mammalian cell cryopreservation. 56. Annual Meeting of the Society for Cryobiology

International audience; Endoluminal Magnetic Resonance Imaging (MRI) is an alternative solution to conventional MRI, which is still not sufficient to image the bowel and colon wall. However, it mainly suffers from coil-sensitivity-map variations with coil-orientations within respect to the main magnetic field (B0). The purpose of this work was to study numerically different coil-geometries and their performances when positioned in different orientations regarding B0. From the simulation results, a solution of a reconfigurable endoluminal-coil using four MEMs switches is proposed. ElectroMagnetic (EM) simulation demonstrated the feasibility to reduce the coil-sensitivity variations by using a combination of Single-loop (SL) and Double-Turn-Loop (DTL) configurations.

Structural neuroimaging studies revealed a consistent pattern of volumetric reductions in both hippocampus (HC) and anterior cingulate cortex (ACC) of individuals with major depressive episode(s) (MDE). This study investigated HC and ACC volume differences in currently depressed individuals (n = 150), individuals with a past lifetime MDE history (n = 79) and healthy controls (n = 287).Non-demented individuals were recruited from a cohort of community-dwelling older adults (ESPRIT study). T1-weighted magnetic resonance images and FreeSurfer Software (automated method) were used. Concerning HC, a manual method of measurement dividing HC into head, body, and tail was also used. General Linear Model was applied adjusting for covariates.Current depression was associated with lower left posterior HC volume, using manual measurement, in comparison to healthy status. However, when we slightly changed sub-group inclusion criteria, results did not survive to correction for multiple comparisons.The finding of lower left posterior HC volume in currently depressed individuals but not in those with a past MDE compared to healthy controls could be related to brain neuroplasticity. Additionally, our results may suggest manual measures to be more sensitive than automated methods.

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement N° 777657; Freezing is the most used bacterial cell preservation technique yet still a process that can be damaging and lead to cell death. Cryosensitivity greatly varies depending on considered species or strains. Fourier Transform Infra-Red (FTIR) spectroscopy is a powerful technique allowing biochemical characterization of major cellular components (lipids, proteins, polysaccharides). However, the exploitation of bacterial spectral features under native aqueous environments is challenging due to the strong absorption of water in the mid-IR region. The identification of cryoresistance markers has thus so far been mainly done using FTIR spectra of dried cells. In this study, three lactic acid bacteria strains were selected for their contrasting cryo-sensitivities. The objective was to combine two complementary approaches: a dynamic approach that measures evolution of peak positions in the lipid region of IR spectra as a function of temperature, and a novel approach using a FTIR microscope enabling higher spatial resolution of cells (~103 to 104 cells) in an aqueous environment. The most cryoresistant strain displayed a strikingly different membrane lipid phase transition compared to the other two: although phase transition happened very abruptly and at a low temperature (-14 °C), in gel phase, lipid membranes of the resistant strain maintained a higher degree of disorganization. These observations could be attributed to high unsaturated fatty acid content (>66% of C18:1). In addition to confirming the lipid membrane’s role in cryoresistance, this study has brought to light the potential role of other cellular components by removing the spectral contribution of water in spectra obtained with the FTIR microscope. This was achieved using a specially developed Matlab program, providing access to a large spectral region encompassing both the protein and carbohydrate regions (1800–975 cm-1). Good discrimination and visualization of population heterogeneity was observed, indicating that markers outside the lipid region must also contribute to cryoresistance

Increasingly more patients exposed to radiation from computed axial tomography (CT) will have a greater risk of developing tumors or cancer that are caused by cell mutation in the future. A minor dose level would decrease the number of these possible cases. However, this framework can result in medical specialists (radiologists) not being able to detect anomalies or lesions. This work explores a way of addressing these concerns, achieving the reduction of unnecessary radiation without compromising the diagnosis. We contribute with a novel methodology in the CT area to predict the precise radiation that a patient should be given to accomplish this goal. Specifically, from a real dataset composed of the dose data of over fifty thousand patients that have been classified into standardized protocols (skull, abdomen, thorax, pelvis, etc.), we eliminate atypical information (outliers), to later generate regression curves employing diverse well-known Machine Learning techniques. As a result, we have chosen the best analytical technique per protocol, a selection that was thoroughly carried out according to traditional dosimetry parameters to accurately quantify the dose level that the radiologist should apply in each CT test.

International audience; Advances in inhomogeneous magnetization transfer (ihMT) imaging have enabled improved volumetric imaging of gray matter. We performed a cortical surface-based analysis of the ihMT ratio (ihMTR) and the inverse ihMT ratio (ihMTRinv) to investigate the distribution of myelin in cortical gray matter. IhMT MRI, and especially ihMTRinv, displayed regional differences in cortical myelination, in agreement with postmortem studies. These findings support the myelin sensitivity and specificity of ihMTRinv and its use for gray matter characterization.

International audience; Aims - Cardiac resynchronization therapy (CRT) plays a pivotal role in the management of patients with heart failure (HF) and wide QRS complex. However, the treatment is plagued by numerous non-responders. Aim of the study is to evaluate the role myocardial work estimated by pressure-strain loops (PSLs) in the comprehension of physiological mechanisms associated with CRT and in the prediction of CRT response. Methods and results - Ninety-seven patients with symptomatic HF (ejection fraction: 27 ± 6%, QRS duration 164 ± 18 ms) undergoing CRT implantation according to current recommendations were retrospectively included in the study. Standard 2D and speckle tracking echocardiography were performed before CRT and at the 6-month follow-up (FU). PSL analysis allowed the calculation of global and regional myocardial constructive work (CW) and wasted work (WW). A > 15% reduction in left ventricular (LV) end-systolic volume at FU defined CRT-positive response (CRT-PR). At FU, 63 (65%) patients responded to CRT. Global CW (CWtot) was significantly increased in CRT-responders. At multivariate analysis, CWtot > 1057 mmHg% (OR 14.69, P = 0.005) and septal flash (OR 8.05, P = 0.004) were the only significant predictors of CRT-PR. CWtot was associated with the entity of CRT-induced myocardial remodelling in both ischaemic (r = -0.55, P

Cryopreservation-related stresses in Lactobacillus delbrueckii SUBSP. Bulgaricus: Global and multi-scale study. 55. Annual Meeting of the Society for Cryobiology

Interdependency of freezing and thawing rates on cryopreserved human t cells. 55. Annual Meeting of the Society for Cryobiology

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Background Usability flaws in medication alerting systems may have a negative impact on clinical use and patient safety. In order to prevent the release of alerting systems that contain such flaws, it is necessary to provide designers and evaluators with evidence-based usability design principles. The objective of the present study was to develop a comprehensive, structured list of evidence-based usability design principles for medication alerting systems. Methods Nine sets of design principles for medication alerting systems were analyzed, summarized, and structured. We then matched the summarized principles with a list of usability flaws in order to determine the level of underlying evidence. Results Fifty-eight principles were summarized from the literature and two additional principles were defined, so that each flaw was matched with a principle. We organized the 60 summarized usability design principles into 6 meta-principles, 38 principles, and 16 sub-principles. Only 15 principles were not matched with a usability flaw. The 6 meta-principles respectively covered the improvement of the signal-to-noise ratio, the support for collaborative working, the fit with a clinician’s workflow, the data display, the transparency of the alerting system, and the actionable tools to be provided within an alert. Conclusions It is possible to develop an evidence-based, structured, comprehensive list of usability design principles that are specific to medication alerting systems and are illustrated by the corresponding usability flaws. This list represents an improvement over the current literature. Each principle is now associated with the best available evidence of its violation. This knowledge may help to improve the usability of medication alerting systems and, ultimately, decrease the harmful consequences of the systems’ usability flaws. Electronic supplementary material The online version of this article (10.1186/s12911-018-0615-9) contains supplementary material, which is available to authorized users.

International audience; The use of receiver endoluminal coils is an attractive solution to achieve locally high spatial resolution in deep regions in the body such as colon wall1. During the radiofrequency (RF) transmit phase, the receiver-coil must be detuned from the RF transmitter-coil to avoid inhomogeneity of the RF magnetic field in proximity and the extra noise in the image due to the mutual inductance between coils2. For this purpose, several detuning methods were proposed in literature such as active detuning based on PINdiode (galvanic)3 or optical connection4. Recently, Micro-Electro-Mechanical-Systems (MEMS) switch(GE Healthcare) was introduced5 to have a fast detuning and a higher SNR6. The purpose of this work was to compare the tuning/detuning characteristics of three detuning circuits and their impacts on the coil performances.

International audience; The multi-modality cardiovascular imaging journal, European Heart Journal-Cardiovascular Imaging, was created in 2012. It has gained an impressive impact factor of 5.99 during its first 5 years and is now the most important imaging journal in Europe. The most important studies from the journal's fourth and fifth years will be highlighted in two reports. Part I of the review will focus on studies in myocardial function, myocardial ischaemia, and emerging techniques in cardiovascular imaging and Part II will focus on valvular heart diseases, heart failure, cardiomyopathies, and congenital heart diseases.

International audience; In regard to aircraft noise mitigation, this paper focuses on noise emission by a simplified nose landing gear (NLG), whose noise sources are identified by the means of sensor array methods. More precisely, following a former characterization of the aeroacoustics by the NLG via dedicated experiments and computations, the subsequent experimental and numerical noise signals are applied two popular sensor array methods of noise localization, namely, classical beam forming (CBF) and deconvolution approach for the mapping of acoustic sources (DAMAS). The resulting noise source maps are then analyzed from both the points of view of phenomenology (NLG noise generation mechanisms) and methodology (noise localization methods and application). The results show how sensor array methods (more especially DAMAS) are capable of revealing the underlying physics of the NLG noise source mechanisms, whether it is within an experimental or a computational context. This speaks in favor of a more systematic use of sensor array methods for investigating the noise physics of aircraft components.; Relativement à la problématique générique de réduction du bruit aéronautique, les travaux présents concernent l'aéroacoustique d'un train d'atterrissage avant d'avion commercial. Ils font suite à des travaux antérieurs dédiés à la caractérisation expérimentale et numérique de la génération acoustique par un train d’atterrissage avant simplifié, dont les sources de bruit sont ici identifiées via une méthode d'antennerie par réseaux de capteurs. Plus précisément, les signaux acoustiques ayant été précédemment mesurés expérimentalement et simulés numériquement sont ici soumis à deux méthodes génériques de localisation de source par réseaux de capteurs, à savoir les techniques Classical Beam Forming (CBF) et DAMAS. Les cartographies de sources de bruit résultantes sont ensuite analysées, à la fois du point de vue de la phénoménologie physique (mécanismes de génération du bruit par le train d’atterrissage) que de celui de la méthodologie mise en œuvre (application des méthodes de localisation du bruit). Les résultats montrent que les méthodes de réseaux de capteurs (et plus particulièrement DAMAS) sont capables de révéler la physique sous-jacente des mécanismes de génération acoustique d’un train d'atterrissage, que ce soit par application au sein d’un contexte expérimental ou numérique. Ceci plaide en faveur d'une utilisation plus systématique des méthodes de réseaux de capteurs pour étudier la physique du bruit aéronautique.

International audience; In regard to aircraft noise mitigation, this paper focuses on noise emission by a simplified nose landing gear (NLG), whose noise sources are identified by the means of sensor array methods. More precisely, following a former characterization of the aeroacoustics by the NLG via dedicated experiments and computations, the subsequent experimental and numerical noise signals are applied two popular sensor array methods of noise localization, namely, classical beam forming (CBF) and deconvolution approach for the mapping of acoustic sources (DAMAS). The resulting noise source maps are then analyzed from both the points of view of phenomenology (NLG noise generation mechanisms) and methodology (noise localization methods and application). The results show how sensor array methods (more especially DAMAS) are capable of revealing the underlying physics of the NLG noise source mechanisms, whether it is within an experimental or a computational context. This speaks in favor of a more systematic use of sensor array methods for investigating the noise physics of aircraft components.; Relativement à la problématique générique de réduction du bruit aéronautique, les travaux présents concernent l'aéroacoustique d'un train d'atterrissage avant d'avion commercial. Ils font suite à des travaux antérieurs dédiés à la caractérisation expérimentale et numérique de la génération acoustique par un train d’atterrissage avant simplifié, dont les sources de bruit sont ici identifiées via une méthode d'antennerie par réseaux de capteurs. Plus précisément, les signaux acoustiques ayant été précédemment mesurés expérimentalement et simulés numériquement sont ici soumis à deux méthodes génériques de localisation de source par réseaux de capteurs, à savoir les techniques Classical Beam Forming (CBF) et DAMAS. Les cartographies de sources de bruit résultantes sont ensuite analysées, à la fois du point de vue de la phénoménologie physique (mécanismes de génération du bruit par le train d’atterrissage) que de celui de la méthodologie mise en œuvre (application des méthodes de localisation du bruit). Les résultats montrent que les méthodes de réseaux de capteurs (et plus particulièrement DAMAS) sont capables de révéler la physique sous-jacente des mécanismes de génération acoustique d’un train d'atterrissage, que ce soit par application au sein d’un contexte expérimental ou numérique. Ceci plaide en faveur d'une utilisation plus systématique des méthodes de réseaux de capteurs pour étudier la physique du bruit aéronautique.

International audience

International audience

International audience; OBJECTIVE: The aim of this study was to test a new automated hepatic volumetry technique by comparing the accuracies and postprocessing times of manual and automated liver volume segmentation methods in a patient population undergoing orthotopic liver transplantation so that liver volume could be determined on pathology as the standard of reference. CONCLUSION: Both manual and automated multiphase MDCT-based volume measurements were strongly correlated to liver volume (Pearson correlation coefficient, r = 0.87 [p < 0.0001] and 0.90 [p < 0.0001], respectively). Automated multiphase segmentation was significantly more rapid than manual segmentation (mean time, 16 ± 5 [SD] and 86 ± 3 seconds, respectively; p = 0.01). Overall, automated liver volumetry based on multiphase CT acquisitions is feasible and more rapid than manual segmentation.

Introduction The Comprehensive in vitro Proarrhythmia Assay (C i PA) is a nonclinical Safety Pharmacology paradigm for discovering electrophysiological mechanisms that are likely to confer proarrhythmic liability to drug candidates intended for human use. Topics covered Key talks delivered at the ‘C i PA on my mind’ session, held during the 2015 Annual Meeting of the Safety Pharmacology Society (SPS), are summarized. Issues and potential solutions relating to crucial constituents [ e.g. , biological materials (ion channels and pluripotent stem cell-derived cardiomyocytes), study platforms, drug solutions, and data analysis] of C i PA core assays are critically examined. Discussion In order to advance the C i PA paradigm from the current testing and validation stages to a research and regulatory drug development strategy, systematic guidance by C i PA stakeholders is necessary to expedite solutions to pending and newly arising issues. Once a study protocol is proved to yield robust and reproducible results within and across laboratories, it can be implemented as qualified regulatory procedure.

International audience; We propose a new imaging technique, demonstrating the bones' edges using the Silent Scan's T1w FatSat sequence. An advanced post-processing coupled with the use of the zero echo-time imaging technology could lead to robust semi- or automatic segmentation. Such technique could guide and facilitate every surgery that needs bone measurements and valuable 3D appreciation or virtual guiding.

Accepted in California Management Review. Soon available in JSTOR; International audience; In 2010, General Electric launched an investigation into how multi-national corporations (MNCs) were adapting to rural emerging markets. A team of 33 executives and three academics examined models ranging from Toyota's vehicle servicing program in East Africa to Nokia's localized mobile handset financing in India to Egis Pharmaceuticals' worker retention incentives in Eastern Europe. The project included 15 case studies from India, China, Africa and Eastern Europe. This article presents common tactics that these MNCs have used to successfully adapt to rural markets in emerging regions across five key organizational functions: product development, distribution, service, financing, and human resources.

International audience

This work received funding from the European Union´s Horizon 2020 research and innovation programme under grant agreement No 777657; International audience; For decades, scientists have looked for the causes of cell cryoinjury so as to identify the optimum conditions for freezing and storing frozen cells. Cell dehydration and intracellular ice formation have been argued as the main mechanisms of cell damage. Maintaining the cells in a vitreous matrix below the glass transition temperature of the surrounding medium is known as a key condition for cell preservation. However, it is only in 2013 that the measurement of the intracellular glass transition of different cell types has been made possible. Moreover, the relevance of intracellular and extracellular vitrification during slow cooling of microorganisms and mammalian cells has been the subject of recent research. The physical events taking place during freezing are reviewed here, focusing on the role of the physical state of the intracellular and extracellular environments in determining the response of cells to stresses encountered during cryopreservation. The implications on cryoprotectants selection, freezing rates, and controlled cooling endpoint to be set for cell storage are discussed.

Cryopreservation is key for delivery of cellular therapies, however the key physical and biological events during cryopreservation are poorly understood. This study explored the entire cooling range, from membrane phase transitions above 0°C to the extracellular glass transition at -123°C, including an endothermic event occurring at -47°C that we attributed to the glass transition of the intracellular compartment. An immortalised, human suspension cell line (Jurkat) was studied, using the cryoprotectant dimethyl sulfoxide. Fourier transform infrared spectroscopy was used to determine membrane phase transitions and differential scanning calorimetry to analyse glass transition events. Jurkat cells were exposed to controlled cooling followed by rapid, uncontrolled cooling to examine biological implications of the events, with post-thaw viable cell number and functionality assessed up to 72 h post-thaw. The intracellular glass transition observed at -47°C corresponded to a sharp discontinuity in biological recovery following rapid cooling. No other physical events were seen which could be related to post-thaw viability or performance significantly. Controlled cooling to at least -47°C during the cryopreservation of Jurkat cells, in the presence of dimethyl sulfoxide, will ensure an optimal post-thaw viability. Below -47°C, rapid cooling can be used. This provides an enhanced physical and biological understanding of the key events during cryopreservation and should accelerate the development of optimised cryobiological cooling protocols.

The European PREMIUM project aims at proposing new eco-friendly strategies to preserve lactic acid bacteria (LAB). One approach considered is the development of new protective agents in order to allow the application of more aggressive drying processes than freeze-drying. Recently, oligosaccharides such as fructo-oligosaccharides and galacto-oligosaccharides have been reported as promising molecules for protecting LAB. It is generally assumed in the literature that direct interaction between membrane and protective agent is important to stabilize membrane during water removal. The ability of oligosaccharides to interact with bacterial membrane will be dependent not only on their sugar composition but also on the lipid membrane composition. The objective of this study is to develop a simplified lipid model representative of bacterial membrane to investigate the specific interaction between oligosaccharides and lipids. The membrane of two strains of lactic acid bacteria exhibiting different freezing resistances and extremely low survival to freeze-drying were fully characterized to determine lipid composition and lipid phase transition. Lipid membrane models of various level of complexity were subsequently designed: i) liposomes and monolayers from bacterial lipid extracts; ii) liposomes from lipid extracts enriched with standard lipids, and ii) liposomes and monolayers made from two standard lipids. The standard lipids were chosen in accordance with the predominant lipids present within the bacterial membrane. The biophysical properties of these models were determined using Fourier Transform Infrared spectroscopy (lipid phase transition) and Langmuir isotherms (surface pressure area isotherms). Two binary lipid models satisfactorily representing the two bacterial strains according to their biophysical properties were set up and could thus be further used to investigate specific interaction between lipid and oligosaccharides.