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A radial-to-femoral pressure gradient (RFPG) can occur in roughly one-third of cardiac surgical patients. Such a gradient has been associated with smaller stature and potentially smaller radial artery diameter. We hypothesized that preoperative radial artery diameter could be a predictor of RFPG. We also investigated the clinical impact of using a femoral versus a radial arterial catheter in terms of vasoactive support.Using ultrasound, we measured the bilateral radial artery diameters of 160 cardiac surgical patients. All arterial pressure values were continuously recorded. Significant RFPG was defined as ≥25 mm Hg in systolic and/or ≥10 mm Hg in mean arterial pressure. One hundred and forty-nine additional patients were used to validate the impact of our observations.Using 78,013 pressure datapoints in 129 patients, 34.8% of patients had an RFPG with a mean duration of 54 ± 48 minutes. Patients with a radial artery diameter1.8 mm were more likely to have an RFPG (n = 14 [48.3%] vs 12 [22.2%];A significant RFPG occurs in one-third of cardiac surgical patients and in 48% of those with a radial artery diameter1.8 mm. The use of a single radial arterial catheter instead of dual radial and femoral catheters was associated with greater vasopressor requirements in the operating room and in the intensive care unit. We do not recommend the use of a single radial artery catheter in cardiac surgery.

Background Right ventricular outflow tract obstruction (RVOTO) is a cause of hemodynamic instability that can occur in several situations, including cardiac surgery, lung transplantation, and thoracic surgery, and in critically ill patients. The timely diagnosis of RVOTO is important because it requires specific considerations, including the adverse effects of positive inotropes, and depending on the etiology, the requirement for urgent surgical intervention. Methods The objective of this systematic review and meta-analysis was to determine the prevalence of RVOTO in adult patients, and the distribution of all reported cases by etiology. Results Of 233 available reports, there were 229 case reports or series, and 4 retrospective cohort studies, with one study also reporting a prospective cohort. Of 291 reported cases of RVOTO, 61 (21%) were congenital, 56 (19%) were iatrogenic, and 174 (60%) were neither congenital nor iatrogenic (including intracardiac tumour). The mechanism of RVOTO was an intrinsic obstruction in 169 cases (58%), and an extrinsic obstruction in 122 cases (42%). A mechanical obstruction causing RVOTO was present in 262 cases (90%), and 29 cases of dynamic RVOTO (10%) were reported. In the 5 included cohorts, with a total of 1122 patients, the overall prevalence was estimated to be 4.0% (1%-9%). Conclusions RVOTO, though rare, remains clinically important, and therefore, multicentre studies are warranted to better understand the prevalence, causes, and consequences of RVOTO., Graphical Abstract Image, graphical abstract

Cardiac arrest is common in critically ill patients with coronavirus disease 2019 (COVID-19) and is associated with poor survival. Simulation is frequently used to evaluate and train code teams with the goal of improving outcomes. All participants engaged in training on donning and doffing of personal protective equipment for suspected or confirmed COVID-19 cases. Thereafter, simulations of in-hospital cardiac arrest of patients with COVID-19, so-called protected code blue, were conducted at a quaternary academic centre. The primary endpoint was the mean time-to-defibrillation. A total of 114 patients participated in 33 “protected code blue” simulations over 8 weeks: 10 were senior residents, 17 were attending physicians, 86 were nurses, and 5 were respiratory therapists. Mean time-to-defibrillation was 4.38 minutes. Mean time-to-room entry, time-to-intubation, time-to-first-chest compression and time-to-epinephrine were 2.77, 5.74, 6.31, and 6.20 minutes, respectively; 92.84% of the 16 criteria evaluating the proper management of patients with COVID-19 and cardiac arrest were met. Mean time-to-defibrillation was longer than guidelines-expected time during protected code blue simulations. Although adherence to the modified advanced cardiovascular life-support protocol was high, breaches that carry additional infectious risk and reduce the efficacy of the resuscitation team were observed., L'arrêt cardiaque est fréquent chez les patients atteints de la maladie à coronavirus 2019 (COVID-19) en phase critique et est associé à une faible survie. La simulation est souvent utilisée pour évaluer et former les équipes chargées de répondre à un code d'urgence afin d'améliorer les résultats de l'intervention. Tous les participants ont suivi une formation sur la façon de mettre et d'enlever l’équipement de protection individuelle pour les cas de COVID-19 présumés ou confirmés. Par la suite, des simulations d'intervention en cas d'arrêt cardiaque de patients atteints de la COVID-19 en milieu hospitalier, selon la procédure de « code bleu protégé », ont été effectuées dans un hôpital universitaire de soins quaternaires. Le critère d’évaluation principal était le délai moyen avant la défibrillation. Au total, 114 participants ont pris part à 33 simulations d'interventions de « code bleu protégé » sur une période de 8 semaines, à savoir 10 résidents de dernière année, 17 médecins traitants, 86 infirmières et 5 inhalothérapeutes. Le délai moyen avant la défibrillation a été de 4,38 minutes. Les délais moyens avant l'entrée dans la chambre, avant l'intubation, avant la première compression thoracique et avant l'administration d’épinéphrine étaient de 2,77, 5,74, 6,31, et 6,20 minutes, respectivement; 92,84 % des 16 critères d’évaluation de la prise en charge appropriée des patients atteints de la COVID-19 en arrêt cardiaque ont été satisfaits. Le délai moyen avant la défibrillation était plus long que celui indiqué dans les lignes directrices durant les simulations d'interventions correspondant au code bleu protégé. Si le protocole modifié de réanimation cardiovasculaire avancée a été bien respecté, des écarts à ce protocole susceptibles d'accroître le risque d'infection additionnelle et de réduire l'efficacité des efforts de réanimation de l’équipe ont cependant été observés.

Pulmonary hypertension (PH) and right ventricular (RV) dysfunction are major complications in cardiac surgery. Intraoperative management of patients at high risk of RV failure should aim to reduce RV afterload and optimize RV filling pressures, while avoiding systemic hypotension, to facilitate weaning from cardiopulmonary bypass (CPB). Inhaled epoprostenol and inhaled milrinone (iEiM) administered in combination before CPB may represent an effective strategy to facilitate separation from CPB and reduce requirements for intravenous inotropes during cardiac surgery. Our primary objective was to report the rate of positive pulmonary vasodilator response to iEiM and, second, how it relates to perioperative outcomes in cardiac surgery.This is a retrospective cohort study of consecutive patients with PH or RV dysfunction undergoing on-pump cardiac surgery at the Montreal Heart Institute from July 2013 to December 2018 (n = 128). iEiM treatment was administered using an ultrasonic mesh nebulizer before the initiation of CPB. Demographic and baseline clinical data, as well as hemodynamic, intraoperative, and echocardiographic data, were collected using electronic records. An increase of 20% in the mean arterial pressure (MAP) to mean pulmonary artery pressure (MPAP) ratio was used to indicate a positive response to iEiM.In this cohort, 77.3% of patients were responders to iEiM treatment. Baseline systolic pulmonary artery pressure (SPAP) (odds ratio [OR], 1.63; 95% confidence interval [CI], 1.24-2.16 per 5 mm Hg; P = .0006) was found to be a predictor of pulmonary vasodilator response, while a European System for Cardiac Operative Risk Evaluation (EuroSCORE II) score6.5% was a predictor of nonresponse to treatment (≤6.5% vs6.5% [reference]: OR, 5.19; 95% CI, 1.84-14.66; P = .002). Severity of PH was associated with a positive response to treatment, where a higher proportion of responders had MPAP values30 mm Hg (42.4% responders vs 24.1% nonresponders; P = .0237) and SPAP values55 mm Hg (17.2% vs 3.4%; P = .0037). Easier separation from CPB was also associated with response to iEiM treatment (69.7% vs 58.6%; P = .0181). A higher proportion of nonresponders had a very difficult separation from CPB and required intravenous inotropic drug support compared to responders, for whom easy separation from CPB was more frequent. Use of intravenous inotropes after CPB was lower in responders to treatment (8.1% vs 27.6%; P = .0052).A positive pulmonary vasodilator response to treatment with a combination of iEiM before initiation of CPB was observed in 77% of patients. Higher baseline SPAP was an independent predictor of pulmonary vasodilator response, while EuroSCORE II6.5% was a predictor of nonresponse to treatment.

A lot of evidence has shown the importance of stimulating cell mechanically during bone repair. In this study, we modeled the challenging fracture healing of a large bone defect in tibial diaphysis. To fill the fracture gap, we considered the implantation of a porous osteoconductive biomaterial made of poly-lactic acid wrapped by a hydrogel membrane mimicking osteogenic properties of the periosteum. We identified the optimal loading case that best promotes the formation and differentiation into bone tissue. Our results support the idea that a patient's rehabilitation program should be adapted to reproduce optimal mechanical stimulations.

International audience; Objectifs : La fibrillation auriculaire postopératoire (FAOP) est une complication majeure après chirurgie cardiaque, et une introduction postopératoire précoce de bêta-bloquants est recommandée pour réduire son incidence. Landiolol, un nouveau bêta-bloquant intraveineux à courte durée d'action, pourrait présenter un profil macrohémodynamique utile et sûr après une chirurgie cardiaque. Les effets métaboliques et hémodynamiques détaillés du landiolol sur les performances cardiaques restent cependant mal documentés. Les auteurs visaient à étudier les effets hémodynamiques et métaboliques dose-dépendants du landiolol dans ce contexte spécifique.Conception : Une étude prospective, randomisée, en double aveugle versus placebo.Cadre : Un hôpital universitaire tertiaire.Participants : Patients adultes programmés pour une chirurgie cardiaque élective avec circulation extracorporelle.Interventions : Des doses incrémentielles de landiolol intraveineux (0,5, 1, 2, 5 et 10 μg/kg/min) ont été administrées dans les 2 heures suivant l'arrivée à l'unité de soins intensifs. Les paramètres macrocirculatoires et les performances cardiaques ont été dérivés de la thermodilution transpulmonaire et de l'échocardiographie transthoracique. Les données métaboliques ont été obtenues à partir de tests sanguins artériels.Mesures et principaux résultats : De janvier à novembre 2019, 58 patients ont été analysés et répartis en un groupe landiolol (n=30) et un groupe contrôle (n=28). La fréquence cardiaque a significativement diminué dans le groupe landiolol (p < 0,01), tandis que la pression artérielle moyenne et le volume d'éjection systolique sont restés inchangés. Aucune modification significative n'a été trouvée dans les performances systolique et diastolique gauche et droite. Les variables métaboliques étaient similaires dans les deux groupes. Une FAOP d'apparition récente est survenue chez 9 (32 %) contre 5 (17 %) patients dans les groupes contrôle et landiolol, respectivement (p = 0,28).Conclusions : La perfusion de landiolol dans la plage de 0,5 à 10 μg/kg/min au cours de la période postopératoire précoce présente un bon profil d'innocuité macrohémodynamique chez les patients en chirurgie cardiaque et pourrait être utile pour prévenir la FAOP.

Background: Postoperative atrial fibrillation (POAF) increases morbidity and mortality after cardiac surgery. Landiolol, a selective ultra-short-acting betablocker has been recently suggested to prevent POAF in the cardiac surgical setting with a good safety profile. Micro- and detailed macrocirculatory effects of landiolol remain however largely unknown in that setting.Methods: We conducted a prospective, randomized, double-blind study versus placebo in patients undergoing conventional cardiac surgery. Incremental doses of intravenous landiolol from 0.5 to 10 μg-1.kg-1.min-1 or placebo were administrated postoperatively. Microcirculatory variables were assessed by both peripheral near-infrared spectroscopy (NIRS) in combination with a vascular occlusion test and sublingual videomicroscopy. Macrocirculatory variables were obtained from transpulmonary thermodilution and transthoracic echocardiography. Results: Fifty-nine adult patients were allocated to the landiolol group (n=30) or the placebo group (n=29) from January to November 2019. Heart rate significantly decreased in the landiolol group (PP=0.05) and stroke volume (P=0.63) were not significantly modified throughout the study. No modification was found in left and right systolic and diastolic ventricular functions except a significant increase in E/A ratio in the landiolol group (P=0.02). No difference was evidenced between groups in microcirculatory parameters at any landiolol dose. POAF occurred in 9 (32%) vs. 5 (17%) patients in placebo and landiolol groups, respectively (P=0.28). Conclusions: Postoperative incremental doses of landiolol up to 10 μg-1.kg-1.min-1 are efficacious to control heart rate without significant alterations in both micro- and macrocirculation following conventional cardiac surgery.

International audience; This study aims at suggesting a new approach to peri-implant healing models, providing a set of taxis-diffusion-reaction equations under the combined influence of mechanical and biochemical factors. Early events of osseointegration were simulated for titanium screw implants inserted into a pre-drilled trabecular bone environment, up to twelve weeks of peri-implant bone healing. Simulations showed the ability of the model to reproduce biological events occurring at the implant interface through osteogenesis. Implants with shallow healing chamber showed higher proportions of lamellar bone, enhanced by the increase of mechanical stimulation. Osteoconduction was observed through the surface treatment model and similar bone healing patterns compared to in vivo studies.

Objective: The aim of this study was to assess, through biological analysis, the local effects and osseointegration of dental implants incorporating surface micro/nanofeatures compared to implants of identical design without surface treatment. Background: Known to impact bone cell behavior, surface chemical and topography modifications target improved osseointegration and long-term success of dental implants. Very few studies assess the performance of implants presenting both micro-and nanofeatures in vivo on the animal models used in preclinical studies for medical device certification. Methods: Implant surfaces were characterized in terms of topography and surface chemical composition. After 4 weeks and 13 weeks of implantation in sheep femoral condyles, forty implants were evaluated through micro-computed tomography, histopathologic, and histomorphometric analyses. Results: No local adverse effects were observed around implants. Histomorphometric analyses showed significantly higher bone-to-implant contact in the coronal region of the surface treated implant at week 4 and week 13, respectively 79.3$\pm$11.2% and 86.4$\pm$6.7%, compared to the untreated implant's 68.3$\pm$8.8% and 74.8$\pm$13%. Micro-computed tomography analyses revealed that healing patterns differed between coronal and apical regions, with higher coronal boneto-implant contact at week 13. Histopathologic results showed, at week 13, bone healing around the surface treated implant with undistinguishable defect margins while the untreated implant still presented bone condensation and traces of the initial drill defect. Conclusion: Our results suggest that the surface treated implant not only shows no deleterious effects on local tissues but also promotes faster bone healing around the implant. (word count: 241, Journal of Periodontal Research, Wiley, 2021

International audience; No abstract available

Obstructive Sleep Apnea (OSA) in children, which has a multifactorial origin, can lead, if not treated, to severe medical complications, growth disturbances, behavioural changes and reduced quality of life. Nowadays, it is underdiagnosed whereas early screening, diagnosis and interdisciplinary treatment are essential. Furthermore, many families and health professionals do not often know where to go when there is suspicion of OSA for a child. Orthodontists are uniquely positioned to screen, to refer to the appropriate specialist and to treat, if needed, patients who may be at high risk for OSA. The authors describe the synergistic means to screen, diagnose and treat paediatric OSA in a collaborative and interactive approach between ENT, orthodontists, pneumo-allergologists, sleep physicians, endocrinologists, orofacial myo-functional therapists and speech therapists. These means which are clinically illustrated in this paper fit the guidelines which have been recently published as white papers by official professional specialists organisations involved in paediatric OSA treatment (AAPD, AAO, FFO, SFORL, SFRMS…). The development of multidisciplinary teams gathering specialists who are conscious about the mutual benefits of the specialties involved in paediatric OSA should contribute to optimize the child treatment care pathway and the short, mid and long term outcomes.

Some AM processes such as directed energy deposition (DED) have typical powder usage efficiencies ranging between 40 and 80%. Since, for a given alloy, powder cost is proportional to its purity, choosing a less expensive powder or reusing powders is interesting for economical and environmental reasons. The work summarized below studied the effect of oxygen content in Ti6Al4V powders on mechanical properties of AM parts fabricated by DED. Three different powders with increasing oxygen content were used to produce specimens and characterize its effect on microstructure and tensile properties before and after heat treatment. Our results show that no clear oxygen pick up was measured from either powder recycling or during printing of parts. Only coarsening of the particle size distribution and the presence of fragmented particles was observed for the recycled powder. Comparing the chemistry of parts vs that of powder feedstock it was determined that for all the tests, the Al content was slightly lower in the parts and that no significant loss of vanadium was noted when printing with new (fresh) powders. On the other hand, V loss was significant in parts made with recycled powders, although still leaving them within acceptable chemistry to respect their original grade 5 classification.

Background Total knee arthroplasty (TKA) reduces knee extensor muscle strength (KES) in the operated limb for several months after the surgery. Immediately after TKA, compared to either inguinal femoral nerve block or placebo, adductor canal block (ACB) better preserves KES. Whether this short-term increase in KES is maintained several weeks after surgery remains unknown. We hypothesized that 48 hours of continuous ACB immediately after TKA would improve KES 6 weeks after TKA, compared to placebo. Methods Patients scheduled for primary unilateral TKA were randomized to receive either a continuous ACB (group ACB) or a sham block (group SHAM) for 48 hours after surgery. Primary outcome was the difference in maximal KES 6 weeks postoperatively, measured with a dynamometer during maximum voluntary isometric contraction. Secondary outcomes included postoperative day 1 (POD1) and day 2 (POD2) KES, pain scores at rest and peak effort, and opioid consumption; variation at 6 weeks of Knee Osteoarthritis Outcome Score, patient satisfaction, and length of hospital stay. Results Sixty-three subjects were randomized and 58 completed the study. Patients in group ACB had less pain at rest during POD1 and during peak effort on POD1 and POD2, consumed less opioids on POD1 and POD2, and had higher median KES on POD1. There was no significant difference between groups for median KES on POD2, variation of Knee Osteoarthritis Outcome Score, patient satisfaction, and length of stay. There was no difference between groups in median KES 6 weeks after surgery (52 Nm [31-89 Nm] for group ACB vs 47 Nm [30-78 Nm] for group SHAM, P= .147). Conclusions Continuous ACB provides better analgesia and KES for 24-48 hours after surgery, but does not affect KES 6 weeks after TKA. Further research could evaluate whether standardized and optimized rehabilitation over the long term would allow early KES improvements with ACB to be maintained over a period of weeks or months.

International audience; This paper demonstrates the use of Surface Plasmon Resonance of core-shell Ag@TiO2 particles in SHINERS experiments. A copper(II) complex grafted onto Ag@TiO2 surface was probed by Raman spectroscopy using resonance excitation profiles vs excitation wavelengths (514, 633 and 785 nm) to tune the Raman signals. Enhancement factors of the SHINERS assembly have been estimated and compared to the SERS effect of unmodified silver NPs colloidal dispersions. Finally, the grafting of the copper(II) complex onto Ag@TiO2 was advantageously compared to the grafting onto Ag@SiO2 shell.

This paper demonstrates the use of surface plasmon resonance of core-shell Ag@TiO2 particles in SHINERS experiments. A copper(ii) complex grafted onto Ag@TiO2 surface was probed by Raman spectroscopy using resonance excitation profiles vs. excitation wavelengths (514, 633 and 785 nm) to tune the Raman signals. Enhancement factors of the SHINERS assembly have been estimated and compared to the SERS effect of unmodified silver NPs colloidal dispersions. Finally, the grafting of the copper(ii) complex onto Ag@TiO2 was advantageously compared to the grafting onto Ag@SiO2 shell.

Powder metallurgy (PM) steels containing boron form an attractive group of alloys because of the important densification that can be achieved through permanent liquid phase sintering (LPS). However, upon solidification, such liquid phase is known to form borides or borocarbides. Recent works have shown that some alloying elements have significant interactions with the LPS of PM steels containing boron. More specifically, it is suspected that the concentration of prealloyed molybdenum influences the formation of boride/borocarbide upon cooling at the end of the sintering cycle. Therefore, the main objective of this work is to describe the relationship that exists between the concentration of prealloyed molybdenum and the crystal structure of the boride/borocarbide eutectic component that typically forms in PM steels containing boron. A master alloy made of iron-manganese-nickel-boron-carbon was utilized to introduce boron, thus providing enhanced sintering through LPS. Characterization in optical and scanning electron microscopy combined with electron-backscattered diffraction and energy-dispersive X-ray spectrometry (EDS) revealed that increasing the prealloyed molybdenum content not only increased the volume fraction of liquid phase but also modified the morphology and the nature of the boron-rich eutectic. Changing the prealloyed molybdenum content from 0.5 to 0.85 wt.% transformed the discontinuous M2B boride to a continuous M23(C,B)6 borocarbide phase, causing a drastic decrease in strength despite the higher densification observed at 0.85 wt.% molybdenum. The effect of molybdenum on the LPS process of boron PM steels is undeniable and was found to occur after the initial formation of the liquid phase. Indeed, differential scanning calorimetry revealed no difference in the endothermic melting peaks temperature for both concentration of molybdenum.

With the advent of the microelectronics and the "smart-devices", the need for micro-sources of energy has risen. To meet these needs, a massive production of microbatteries is required in the next decades. Physical vapor deposition (PVD) is the process commonly used to fabricate thin film all solid state microbatteries. Commercially, LiCoO2 and lithium are used respectively as positive and negative electrodes. LiPON is commonly used as solid electrolyte because of its good ionic conductivity, good thermal and electrochemical stability and also for its good interfacial stability with the electrodes. However, the PVD process requires very expensive deposition machineries, with a high energy cost, which impact consequently the price and the development of the microbatteries. Processes involving liquid step, such as ink jet printing or screen printing propose cheaper machinery and much higher production rate. Moreover, these techniques are precise enough to deposit any pattern either by located drop jetting or by use of specific mask fitting the desired shape. In this communication, we will report our efforts to develop all or partially printed microbatteries. We have worked on replacing LiPON by another solid electrolyte which could be deposited by printing. Ionogels are solid electrolyte in which an ionic liquid (IL) is confined within a solid host network. Although solid like electrolytes, ionogels are formed from a liquid precursor, and are thus appropriate materials for the purpose. The liquid precursor is obtained by mixing the IL with organic, inorganic or hybrid monomers that are then polymerized to build in-situ the confining network. Furthermore, ionogels show good ionic conductivity and also good thermal and electrochemical stability, thus making them attractive solid electrolyte for lithium batteries. The time required to form a fully solidified material can vary depending on the nature of the confining network and the polymerization process. By using photo-polymerization, which is very fast, the manufacturing time is lesser than an hour, while for LiPON it can last more than ten hours. We have identified a promising printable photo-polymerizable ionogel composition with high ionic conductivity, pressure-sensitive-adhesive character, low interface resistance with lithium electrode, which allows stable cycling of LiFePO4/lithium cells, at least up to 1200 cycles at ambient temperature, C/5 rate and for surface capacities typical of microbatteries, e.g. 0.15 mAh cm-2. This ionogel is based on short molecular weight monomers with high content of polymerizable functionalities (triacrylate and diacrylate) and ILs composed of fluorinated sulfonylimide anions combined with alkylated pyrrolidinium cations [1]. We have evaluated the feasibility of making all or partially printed microbatteries with this printable solid electrolyte, not starting from the ground but trying to fit in an existing industrial process that uses PVD for manufacturing microbatteries. Microbatteries assembled from a dense PVD made LiCoO2 layer, a printed photo-polymerized ionogel, and a lithium layer exhibit good performance. However, the photo-polymerized ionogel showed very low compatibility when the lithium electrode is directly deposited by PVD on the top of it. Thus the lithium electrode must be mechanically assembled with the ionogel electrolyte. Microbatteries assembled from a printed porous LiFePO4 composite layer [2], a printed photo-polymerized ionogel, and lithium layer (an already made foil or evaporated layer and mechanically pressed on the ionogel surface) also demonstrated good performance. Acknowledgements Financial funding from the project TOURS 2015 n° O12590-418393 (Programme d’Investissement d’Avenir – FSN – AAP Nanoélectronique n°1) is acknowledged. References [1] D. Aidoud, A. Etiemble, D. Guy-Bouyssou, E. Maire, J. Le Bideau, D. Guyomard, B. Lestriez, "Interfacial stability and electrochemical behavior of Li/LiFePO4 microbatteries using novel soft and weakly adhesive photo-ionogel electrolytes”, J. Power Sources, 330, 2016, 92-103. [2] P.-E. Delannoy, B. Riou, T. Brousse, J. Le Bideau, D. Guyomard, B. Lestriez, “Ink-jet printed porous composite LiFePO4 electrode from aqueous suspension for microbatteries”, J. Power Sources, 2015, 287, 261-268.

This study compares the normative expectations of 1315 Québécois survey-takers about the responsibilities of spouses and ex-spouses, on the one hand, and adult children and stepchildren, on the other hand, regarding the support they are to offer an elderly family member with incapacities. The comments of survey-takers in relation to fictional yet concrete scenario descriptions provided a basis with which to identify respondents' expectations along with the social factors surrounding these expectations. The results of this survey suggest that the nature and scale of support-related expectations vary according to the family tie with elderly relative. Expectations toward spouses are high and unmitigated, whereas expectations toward ex-spouses and adult stepchildren appear to be limited. Expectations toward adult children are more pronounced than those exhibited toward stepchildren. Where offspring are specifically concerned, expectations are strongly influenced by the given context; for this category of survey-taker, the demands of support should not interfere with their family life and career.

Chemical EOR methods have become an increasingly attractive option for heavy oil reservoirs where thermal methods cannot be applied, like in thin reservoirs. The use of surfactants for heavy oil is only reported, both at lab and field scale, in a limited number of cases and mostly in combination with alkali to benefit from the generation of in-situ surfactants. However, operational issues (such as scale or corrosion) associated with the use of alkali as well as negative impacts on project logistics are often mentioned. The objective of this work is to demonstrate at lab scale the efficiency of alkaline-free surfactant-polymer processes in the context of heavy oil reservoirs. The present investigation is focused on a Canadian heavy oil (14°API and 1400 cP) in representative reservoir conditions (high permeability sandstone, temperature of 35°C, low salinity). A dedicated synthetic surfactant formulation is designed using a screening methodology based on a robotic platform. Ultra-low interfacial tensions are evidenced from phase behavior and confirmed by spinning-drop tensiometry. Oil recovery performances of the surfactant formulation are then evaluated in corefloods. Cores at Swi are first polymer flooded until no oil is produced to reach a residual oil saturation. Surfactant-Polymer formulations are then injected. Typical results show that additional oil is produced as a continuous oil bank (up to 100% ROIP depending on the slug size) and with a moderate adsorption if a salinity gradient strategy is applied (typically 0.2 mg surfactant per g of rock). This indicates that the surfactant is able to mobilize most of the residual oil. The results of this exploratory investigation show that alkaline-free surfactant-polymer processes could be applied to heavy oil reservoirs while minimizing operational issues. Complementary work will also be presented on optimization of the process through injection strategy improvement and surfactant dosage reduction as well as on extrapolation of the lab results to field-scale technical and economical feasibility.

This study compares the normative expectations of 1315 Québécois survey-takers about the responsibilities of spouses and ex-spouses, on the one hand, and adult children and stepchildren, on the other hand, regarding the support they are to offer an elderly family member with incapacities. The comments of survey-takers in relation to fictional yet concrete scenario descriptions provided a basis with which to identify respondents' expectations along with the social factors surrounding these expectations. The results of this survey suggest that the nature and scale of support-related expectations vary according to the family tie with elderly relative. Expectations toward spouses are high and unmitigated, whereas expectations toward ex-spouses and adult stepchildren appear to be limited. Expectations toward adult children are more pronounced than those exhibited toward stepchildren. Where offspring are specifically concerned, expectations are strongly influenced by the given context; for this category of survey-taker, the demands of support should not interfere with their family life and career.

Les conjoints sont de loin les principaux responsables et dispensateurs de soins aux personnes âgées avec incapacités. Pourtant, cet engagement semble ignoré tant par les professionnels que par la plupart des chercheurs qui semblent le tenir pour acquis. Cet article aborde la transition au soin et l’engagement des conjoints sous l’angle des enjeux identitaires, notamment l’identité assignée par la société, associée aux classements sociaux de conjoint et de genre, et l’identité que les conjoints âgés semblent s’attribuer. L’identité conjugale, telle que conçue par des répondants de trois générations de Québécois et les conjoints, est fondée sur un devoir de solidarité où contrat et confiance sont en jeu., Spouses are far and away the caregivers primarily responsible for looking after elderly persons suffering from disabilities. And yet both professionals and most researchers seem to overlook their commitment or to take it for granted. In this article the author will be looking at spousal transition and commitment to the role of caregiver from the angle of issues of identity, and more particularly the identity assigned by society at large, based on the social and gender classification of the spouse, and the identity that elderly spouses appear to attach to themselves. Conjugal identity, as perceived by three generations of respondents and spouses, is based on a duty of solidarity involving both a consensual contract and trust.

This study was designed to compare the effects of dietary supplementation with nondigestible carbohydrates, differing in fermentability by colonic bacteria, on hepatic steatosis in growing obese Zucker rats. Male Zucker fa/fa rats were divided into three groups: a control group that received the basal diet, a fructan group that received 10 g highly fermented Synergy 1/100 g diet and a cellulose group that received 10 g poorly fermented Vivapur Microcrystalline cellulose/100 g diet. Rats consuming fructan had a lower energy intake, a lower body weight and less triacylglycerol accumulation in the liver as assessed in vivo by nuclear magnetic resonance (NMR) spectroscopy, and ex vivo by biochemical and histochemical analysis compared with the control and/or cellulose groups. The high fermentation of fructans compared with cellulose was reflected by greater cecal contents and by a twofold greater propionate concentration in the portal vein of rats fed fructan compared with those fed cellulose. By measuring the capacity of hepatocytes isolated from liver of Zucker rats to synthesize triglycerides or total lipids from different precursors, we showed that propionate, at the concentrations measured in the portal vein of rats treated with fructan, selectively decreased the incorporation of acetate into total lipids, a phenomenon that could contribute, along with the lower energy intake, to less triglyceride accumulation in the liver of obese Zucker rats fed dietary fructans.