Establishing building environmental targets to implement a low carbon objective at the district level: methodology and case study

To face climate change, greenhouse gas (GHG) emission targets are specified into national policies. In France, the objective is to divide by 4 (Factor 4) the GHG emissions by 2050 comparing to 1990. The built environment, as a main contributor, is targeted by these policies: the future 2020 French regulation will set up GHG emissions targets for the building life cycle. However, the implementation of this regulation and its labels into real-estate development is challenging because it is uncorrelated to factor 4, architectural and technical constraints due to these labels are yet unknown and targets are defined at building scale and not at the district scale. This paper offers some answers to this challenges based on a case study from a real estate developer who wanted to implement a 2025 objective to a new district in Lyon, France. It was done thanks to a review on Factor 4 and labels' history, on calculation of GHG emissions from 1990s building and objectives for 2050 and illustration of labels' constraints. Finally, objectives were allocated at building scale to meet the overall district ambition

A consensus protocol for functional connectivity analysis in the rat brain

Task-free functional connectivity in animal models provides an experimental framework to examine connectivity phenomena under controlled conditions and allows for comparisons with data modalities collected under invasive or terminal procedures. Currently, animal acquisitions are performed with varying protocols and analyses that hamper result comparison and integration. Here we introduce StandardRat, a consensus rat functional magnetic resonance imaging acquisition protocol tested across 20 centers. To develop this protocol with optimized acquisition and processing parameters, we initially aggregated 65 functional imaging datasets acquired from rats across 46 centers. We developed a reproducible pipeline for analyzing rat data acquired with diverse protocols and determined experimental and processing parameters associated with the robust detection of functional connectivity across centers. We show that the standardized protocol enhances biologically plausible functional connectivity patterns relative to previous acquisitions. The protocol and processing pipeline described here is openly shared with the neuroimaging community to promote interoperability and cooperation toward tackling the most important challenges in neuroscience

25th annual computational neuroscience meeting: CNS-2016

The same neuron may play different functional roles in the neural circuits to which it belongs. For example, neurons in the Tritonia pedal ganglia may participate in variable phases of the swim motor rhythms [1]. While such neuronal functional variability is likely to play a major role the delivery of the functionality of neural systems, it is difficult to study it in most nervous systems. We work on the pyloric rhythm network of the crustacean stomatogastric ganglion (STG) [2]. Typically network models of the STG treat neurons of the same functional type as a single model neuron (e.g. PD neurons), assuming the same conductance parameters for these neurons and implying their synchronous firing [3, 4]. However, simultaneous recording of PD neurons shows differences between the timings of spikes of these neurons. This may indicate functional variability of these neurons. Here we modelled separately the two PD neurons of the STG in a multi-neuron model of the pyloric network. Our neuron models comply with known correlations between conductance parameters of ionic currents. Our results reproduce the experimental finding of increasing spike time distance between spikes originating from the two model PD neurons during their synchronised burst phase. The PD neuron with the larger calcium conductance generates its spikes before the other PD neuron. Larger potassium conductance values in the follower neuron imply longer delays between spikes, see Fig. 17.Neuromodulators change the conductance parameters of neurons and maintain the ratios of these parameters [5]. Our results show that such changes may shift the individual contribution of two PD neurons to the PD-phase of the pyloric rhythm altering their functionality within this rhythm. Our work paves the way towards an accessible experimental and computational framework for the analysis of the mechanisms and impact of functional variability of neurons within the neural circuits to which they belong

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Susceptibility-sensitive MRI: A tool for vascular and molecular imaging

Cette thèse présente l’utilisation et l’optimisation de méthodes d’imagerie par résonance magnétique (IRM) pour atteindre deux objectifs principaux : 1) imager et caractériser la vascularisation cérébrale de la souris sans agent de contraste sous différentes conditions d’anesthésie et 2) caractériser et quantifier des particules d’oxyde de fer (POF) utilisées en IRM moléculaire chez la souris. Un accent particulier est mis sur les méthodes d’IRM sensibles à la susceptibilité magnétique, comme l’imagerie quantitative de susceptibilité et la quantification de R2*. L’atteinte du premier objectif repose sur la détection de la désoxyhémoglobine, une molécule endogène hautement paramagnétique. L’extraction des vaisseaux sanguins à partir des images d’IRM montre qu’une anesthésie à la kétamine-xylazine ou la dexmédétomidine rend visible beaucoup plus de vaisseaux qu’une anesthésie à l’isoflurane pour les mêmes fractions d’oxygène inspiré. Nous présentons également une méthode qui permet de différencier les veines et les artères. Pour réaliser le deuxième objectif, nous nous intéressons à une POF déjà utilisée avec succès en IRM moléculaire : la Dynabeads® MyOne™ Tosylactivated. Cette POF peut être conjuguée à un anticorps, de sorte qu’elle se lie à la molécule cible de l’anticorps in vivo. Nous mesurons pour la première fois les relaxivités et la susceptibilité molaire de cette POF à 7T. Nous présentons également une nouvelle mire bimodale obtenue en conjuguant cette POF à un fluorophore. Cette mire permet d’étudier l’effet des POF sur le signal d’IRM à l’aide d’images de microscopie. Enfin, nous montrons que la quantité de POF peut être quantifiée à partir du taux de relaxation R2* et de la susceptibilité χ mesurés in vivo dans un modèle d’inflammation cérébrovasculaire chez la souris. Ces méthodes de quantification raffinent l’IRM de POF.Abstract: This thesis presents the use and the optimization of magnetic resonance imaging (MRI) methods to achieve two main goals: 1) to image and characterize the vasculature of the mouse brain without contrast agent under various anesthetic conditions and 2) to characterize and quantify microparticles of iron oxide (MPIOs) employed for molecular MRI in the mouse. There is a particular focus on methods sensitive to magnetic susceptibility, such as R2* mapping and Quantitative Susceptibility Mapping. Achieving the first goal relies on the detection of deoxyhemoglobin, a highly paramagnetic endogenous molecule. The extraction of blood vessels from T2*-weighted MR images shows that anesthesia under ketamine-xylazine or dexmedetomidine allows seeing a much more significant fraction of the vasculature than isoflurane anesthesia for similar fractions of inspired O2. We also present a method that allows differentiating veins from arteries. To achieve the second goal, we focus on an MPIO used several times for molecular MRI: the Dynabeads® MyOne™ Tosylactivated. This MPIO can be conjugated to a biomarker’s antibody, after which it binds to the biomarker in vivo. We report for the first time the MRI relaxivities and molar susceptibility of this MPIO at 7T. We also present a new bimodal phantom obtained after conjugating the MPIOs to a fluorophore. Imaging this phantom with both MRI and light sheet microscopy allows studying the link between heterogeneous MPIO distributions and MR signal. Finally, we show that MPIOs quantities can be estimated from R2* and χ maps acquired in vivo in a mouse cerebrovascular inflammation model. This mapping of MPIO quantities adds to the usual MPIO negative contrast quantification without extra acquisition, refining molecular imaging of MPIOs

In vivo magnetic resonance imaging of the mouse neurovasculature : optimization and acceleration by compressed sensing

Résumé : Imager la vascularisation cérébrale de la manière la plus exacte, précise et rapide possible représente un enjeu important pour plusieurs domaines de recherche. En plus d’aider à mieux comprendre le fonctionnement normal du cerveau, cela peut servir à caractériser diverses pathologies ou à développer de nouveaux traitements. Dans un premier temps, ce mémoire présente l’optimisation d’une technique d’angiographie cérébrale in vivo chez un modèle animal fréquemment utilisé, la souris. La technique emploie une séquence d’imagerie par résonance magnétique (IRM) 3D pondérée en susceptibilité ainsi qu’un agent de contraste, le Resovist. Les paramètres d’acquisition à l’IRM ont été optimisés à l’aide d’images acquises avant l’injection du Resovist. Ces paramètres permettent d’imager le cerveau entier en 41 minutes avec une résolution de 78 × 78 × 104 μm3. L’emploi d’une pondération en susceptibilité offre une excellente sensibilité aux petits vaisseaux (diamètre ≃ 40μm). L’analyse des images permet d’extraire des informations sur la morphologie vasculaire. Dans un second temps, la méthode de l’acquisition compressée (AcqC) a été implémentée dans le but d’accélérer l’acquisition des images angiographiques. La méthode de l’AcqC utilise des hypothèses de compressibilité des images pour diminuer la quantité de données acquise. L’AcqC a jusqu’à présent principalement été développée pour des images réelles (au sens des nombres complexes). Or, les images angiographiques obtenues présentent d’importantes variations de phase en raison de la pondération en susceptibilité. La présence de ces variations diminue d’une part la force des hypothèses de compressibilité habituelles et rend d’autre part l’espace-k moins propice au sous-échantillonnage requis par l’AcqC. En raison de ces deux facteurs, l’AcqC standard s’avère inefficace pour accélérer l’acquisition des images angiographiques acquises. Leur mise en lumière suggère cependant différentes pistes pour améliorer l’AcqC appliquée aux images comportant d’importantes variations de phase.Abstract : Imaging neurovasculature with highest exactitude, precision and speed is of critical importance for several research fields. Beside providing an insight on normal brain activity, it can help characterize numerous pathologies or develop novel treatments. This thesis presents in its first part the optimization of a cerebral angiographic in vivo technique in a frequently used animal model, the mouse. The technique uses both a 3D magnetic resonance imaging (MRI) susceptibility weighted sequence and a strongly paramagnetic contrast agent, Resovist. MRI acquisition parameters were optimized using images acquired before contrast agent injection. Those parameters allow whole brain vascular imaging of the mouse brain in 41 minutes with a 78 × 78 × 104 μm3 resolution. Susceptibility weighting offers an excellent detection sensitivity for small vessels (diameter ≃ 40μm). Image treatment and analysis allow the extraction of vascular morphological information such as vessel size and vessel density. In the second part of this thesis, an attempt to accelerate angiographic images acquisition using the compressed sensing (CS) method is presented. CS method aims at reducing the acquired data by using compressibility hypothesis on images. Presently, CS is mainly developped for real images (within the meaning of complex numbers). However, the previously obtained angiographic images contain important phase variations due to the susceptibility weighting. First, those variations reduce the strength of the compressibility hypothesis normally used in CS. Second, those same variations make information distribution in k-space less appropriate for the undersampling required by CS. For those reasons, standard CS does not allow significant acceleration of the acquisition process for the presented angiographic technique. Studying those reasons however suggests new ways to increase CS efficiency when applied to images with important phase variations

In vivo magnetic resonance imaging of the mouse neurovasculature : optimization and acceleration by compressed sensing

Résumé : Imager la vascularisation cérébrale de la manière la plus exacte, précise et rapide possible représente un enjeu important pour plusieurs domaines de recherche. En plus d’aider à mieux comprendre le fonctionnement normal du cerveau, cela peut servir à caractériser diverses pathologies ou à développer de nouveaux traitements. Dans un premier temps, ce mémoire présente l’optimisation d’une technique d’angiographie cérébrale in vivo chez un modèle animal fréquemment utilisé, la souris. La technique emploie une séquence d’imagerie par résonance magnétique (IRM) 3D pondérée en susceptibilité ainsi qu’un agent de contraste, le Resovist. Les paramètres d’acquisition à l’IRM ont été optimisés à l’aide d’images acquises avant l’injection du Resovist. Ces paramètres permettent d’imager le cerveau entier en 41 minutes avec une résolution de 78 × 78 × 104 μm3. L’emploi d’une pondération en susceptibilité offre une excellente sensibilité aux petits vaisseaux (diamètre ≃ 40μm). L’analyse des images permet d’extraire des informations sur la morphologie vasculaire. Dans un second temps, la méthode de l’acquisition compressée (AcqC) a été implémentée dans le but d’accélérer l’acquisition des images angiographiques. La méthode de l’AcqC utilise des hypothèses de compressibilité des images pour diminuer la quantité de données acquise. L’AcqC a jusqu’à présent principalement été développée pour des images réelles (au sens des nombres complexes). Or, les images angiographiques obtenues présentent d’importantes variations de phase en raison de la pondération en susceptibilité. La présence de ces variations diminue d’une part la force des hypothèses de compressibilité habituelles et rend d’autre part l’espace-k moins propice au sous-échantillonnage requis par l’AcqC. En raison de ces deux facteurs, l’AcqC standard s’avère inefficace pour accélérer l’acquisition des images angiographiques acquises. Leur mise en lumière suggère cependant différentes pistes pour améliorer l’AcqC appliquée aux images comportant d’importantes variations de phase.Abstract : Imaging neurovasculature with highest exactitude, precision and speed is of critical importance for several research fields. Beside providing an insight on normal brain activity, it can help characterize numerous pathologies or develop novel treatments. This thesis presents in its first part the optimization of a cerebral angiographic in vivo technique in a frequently used animal model, the mouse. The technique uses both a 3D magnetic resonance imaging (MRI) susceptibility weighted sequence and a strongly paramagnetic contrast agent, Resovist. MRI acquisition parameters were optimized using images acquired before contrast agent injection. Those parameters allow whole brain vascular imaging of the mouse brain in 41 minutes with a 78 × 78 × 104 μm3 resolution. Susceptibility weighting offers an excellent detection sensitivity for small vessels (diameter ≃ 40μm). Image treatment and analysis allow the extraction of vascular morphological information such as vessel size and vessel density. In the second part of this thesis, an attempt to accelerate angiographic images acquisition using the compressed sensing (CS) method is presented. CS method aims at reducing the acquired data by using compressibility hypothesis on images. Presently, CS is mainly developped for real images (within the meaning of complex numbers). However, the previously obtained angiographic images contain important phase variations due to the susceptibility weighting. First, those variations reduce the strength of the compressibility hypothesis normally used in CS. Second, those same variations make information distribution in k-space less appropriate for the undersampling required by CS. For those reasons, standard CS does not allow significant acceleration of the acquisition process for the presented angiographic technique. Studying those reasons however suggests new ways to increase CS efficiency when applied to images with important phase variations

Double-scope rendezvous technique: a safe way to perform an endoscopic ultrasound-guided ileorectal anastomosis after complete stenosis

International audienc

Effect of superficial and deep parasternal blocks on recovery after cardiac surgery: study protocol for a randomized controlled trial

BackgroundPain is frequent after cardiac surgery and source of multiple complications that can impair postoperative recovery. Regional anesthesia seems to be an interesting technique to reduce the pain in this context, but its effectiveness in improving recovery has been poorly studied so far. The objective of this study is to compare the effectiveness of two of the most studied chest wall blocks in cardiac surgery, i.e., the superficial and the deep parasternal intercostal plane blocks (SPIP and DPIP respectively), in addition to standard care, versus the standard care without regional anesthesia, on the quality of postoperative recovery (QoR) after cardiac surgery with sternotomy.MethodsThis is a single-center, single-blind, controlled, randomized trial with a 1:1:1 ratio. Patients (n = 254) undergoing cardiac surgery with sternotomy will be randomized into three groups: a control group with standard care and no regional anesthesia, a SPIP group with standard care and a SPIP, and a DPIP with standard care and a DPIP. All groups will receive the usual analgesic protocol. The primary endpoint is the value of the QoR evaluated by the QoR-15 at 24&nbsp;h after the surgery.DiscussionThis study will be the first powered trial to compare the SPIP and the DPIP on global postoperative recovery after cardiac surgery with sternotomy.Trial registrationClinicalTrials.gov NCT05345639. Registered on April 26, 2022