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The purpose of this chapter is to make visible and appreciate the transformative possibilities of collaborating, and how to work together in a liminal space. In this meta-reflective chapter, we collaborate to demonstrate the argument that collaborative writing can achieve much more than the simple goal of producing an article or book chapter. Collaboration provides rich opportunities to develop new understandings and deeper collegial relationships. Entering a collaborative relationship requires stepping over the threshold between familiar, discursively produced positions and entering new, unfamiliar epistemological and ontological frameworks. Developing collaboration means always ‘becoming’. Gaining new understandings is an ongoing connection-oriented process, so collaboration requires an ethic of care, and valuing rather than tolerating alternate perspectives. Learning from each other demands a willingness to explore different meanings and in the process to find common ground with language that appears to be stable but is itself always shifting and changing. Collaboration for us is not simply the coordination of efforts towards a common goal, but is dependent on our differences and the interactions they foster. Furthermore, we suggest that by privileging equity over equality, we can avoid quantifiably measuring individual contributions. Participation and interaction are valued as well as sharing existing knowledge, for the challenges and the rewards come into being through working together in gaining new insights.

Superconducting rf cavities are used in particle accelerators to provide energy to the particle beam. Such cavities are mostly fabricated in niobium and often operated in superfluid helium. One of their limits of operation is the appearance of a local quench, initiated by a local field enhancement due to a defect, which leads to a normal conducting transition of the cavity. Localizing the quench area can be achieved with temperature mapping systems. Another method is the use of second sound wave propagation in superfluid helium. Measuring the time of propagation of these waves from quench location to special sensors, called oscillating superleak transducers (OSTs), and using their well-known velocity should allow trilateration. However, most of the experimental measurements on cavities show premature signals, i.e., the second sound signals arrive earlier on the OSTs than expected. This paper presents several quench experiments on cavities equipped with OSTs and temperature mapping quench detection systems. Two hypotheses can explain the observed premature signals. The first one assesses faster propagation in helium. An experimental setup has been developed for testing this hypothesis, where second sound is created by a localized heater in a controlled environment up to ${4.3\text{ }\text{ }\mathrm{kW}/\mathrm{cm}}^{2}$ and 2.8 J. Premature signals could not be verified in this setup. A second hypothesis based on a simple model including several processes in niobium and second sound propagation in helium is discussed. The model improves significantly the prediction of the times of arrival of the second sound waves. The overall study shows that the processes in niobium play a prominent role in the second sound detection for superconducting cavities.

International audience; The study deals with the ‘vanadium (IV) sulfate’ and ‘vanadium (V) pentoxide’ dissolution processes in 3 M H2SO4 aqueous media. Several measurements of the concentration of dissolved VO2+ and VO2+ were achieved in the range of 0–40 °C, and allowed to understand the limitations of the dissolution process (‘endothermic’ – mass transport for VOSO4 and ‘exothermic’ – reaction with the proton for V2O5). In addition, simple models were proposed (diffusion/accumulation for VOSO4 and kinetic rate for V2O5) and their resolution leads to theoretical kinetic equations describing the temporal evolution of these concentrations with satisfactory agreement with the experimental curves. Solubility’s data and their temperature dependence were determined for both vanadium compounds involved.

Elwyn Richardson’s experimental approach to teaching and learning and Oruaiti was officially sanctioned, but the history of education in Aotearoa/New Zealand shows that teachers have been typically conformist. In this article, I suggest that positivist paradigms from the industrial age continue to shape classroom teaching, partly because of norms of individualism, and partly because neoliberal understandings have become central in the functioning of our schools and society. Teaching is an activity that promotes the ethics of a community or society by promulgating some ideas and marginalising others. In Aotearoa/New Zealand, many of our students struggle with the collective orientation of their community traditions and the societal emphasis on individualism. Modernist beliefs in social progress through technology still permeate education policy. Promoting communitarian understandings requires more open-ended approaches to teaching such as Richardson demonstrated. With digital technologies gaining p...

Arterial stiffness is a predictor of cardiovascular mortality. It increases with age and is accelerated by hypertension and other cardiovascular risk factors. In addition to the disease state, arterial stiffness increases from the proximal to the distal arterial compartments. Concurrent assessment of various vessels from the same subjects is unavailable in the literature. The aim of this work was to quantify an intrinsic mechanical feature, namely, wall stiffness, of the common carotid artery (CCA) and brachial artery (BA). CCAs and BAs of healthy adolescents were investigated. Cine loops of CCA and BA B-mode data were digitally recorded at the same clinical examination, and arterial elastic moduli were estimated off-line with our proprietary non-invasive Imaging-based BioMarker (ImBioMark) algorithm. The 11 study subjects were 14.4 ± 1.2 years old, with normal body habitus and blood pressures 112.3 ± 10.6/63.6 ± 5.7 mm Hg. BAs had a higher elastic modulus than CCAs (arterial elastic moduli: 129.73 ± 25.67 kPa vs. 49.55 ± 14.75 kPa, p0.001). There was a positive correlation between the BA and CCA (slope = 0.36, intercept = 111.62 kPa, R(2) = 0.045). This article documents, for the first time, a correlation between the CCA and BA of the same subject, under the same conditions. We previously reported preliminary data for the aorta and documented the effect of aging on the CCA; we now intend to study the femoral artery as well and include age stratification to pursue our investigations. The results reported here can be seen as the first step toward mechanical mapping of the arterial tree.

Kawasaki disease (KD) is a systemic vasculitis, classically affecting large- and medium-size arteries. The coronary arteries draw most of the clinical attention, whereas few studies have taken interest in the ascending aorta. Using a proprietary imaging-based mechanical biomarker (ImBioMark), we sought to determine aortic stiffness in KD compared to systemic hypertension (HTN) and healthy children. We evaluated parasternal long-axis views focused on the ascending aorta in 20 controls, 12 KD, and 8 HTN as a comparative clinical model of vascular stiffness. We calculated systolic and diastolic aortic wall strain with ImBioMark. Strain was tested for normality against height, systolic, and diastolic blood pressure in normal subjects. Strain from KD and HTN was normalized (Z score) accordingly. Z score comparisons were performed using nonparametric statistics. Age was similar between KD and HTN (9.1 ± 5.3 and 9.9 ± 5.3 years old; p = NS). Systolic and diastolic strain values were normally distributed against height, systolic blood pressure, and diastolic blood pressure in healthy subjects. HTN subjects had abnormal systolic and diastolic strain values (p < 0.0001). Whereas KD subjects had normal diastolic strain, systolic strain was significantly lower (p < 0.001), and systolic strain was intermediate between controls and HTN. There were no significant differences in aortic strain among KD, however, according to the presence of coronary artery aneurysms. Despite normal blood pressure, the ascending aorta in KD exhibits reduced strain during systole. This may reflect in situ rigidity of the aorta. The normal diastolic strain in KD may, in contrast, reflect normal peripheral vascular resistance.

International audience; Cryomodules of the superconducting accelerator SPIRAL 2 have been successfully qualified and are now under commissioning on the linac at GANIL (France). This paper presents the successful results of the power conditioning of the couplers both on a test bench in Grenoble and during the cryomodules qualification. It also shows the influence of some factors, such as surface state and experiencing a cavity quench around the antenna, on the power conditioning process (duration, quality).

Cardiovascular disease (CVD) remains the main killer worldwide, despite major advances in healthcare and therapeutic measures. Much effort is invested in preventive care in order to improve health outcomes further. Vascular physiology modulation is a key element for early diagnosis and risk stratification. Our long-term objective is to facilitate identification of individuals at increased risk of CVD earlier in life. This would allow primary prevention, prior to the onset of clinical disease. We have documented an enhanced technique where we studied arterial stiffness, an independent predictor of CVD. Our method is able to detect functional changes prior to the onset of anatomical modification in youth. The aim of this work is to establish a longitudinal mechanical mapping of the arterial tree in healthy individuals. We report clinical data on the common carotid, abdominal aorta, and brachial arteries. These preliminary results will serve as a foundation for CVD research.

Several studies have suggested that intrauterine growth restriction (IUGR) increases the risk of cardiovascular disease and early atherosclerosis. Early detection of arteriopathy is essential to early intervention. Although arterial intima-media thickness (IMT) is considered an index of subclinical atherosclerosis in the adult, its validity in pediatric patients may be limited. We have recently introduced a novel imaging-based biomarker (ImBioMark) to assess intrinsic mechanical features of the arterial wall from B-mode ultrasound data. The aim of the work described here was to evaluate the potential of ImBioMark in investigation of cardiovascular health status at the level of the common carotid artery (CCA) in adolescents born after IUGR. We also compared ImBioMark results with automated IMT measurements, a well-established biomarker used in clinical practice and research. The potential sequelae of IUGR on the CCA were examined in a group of adolescents in comparison with healthy controls. Patients with IUGR (n = 7) were 13.85 ± 0.46 y old; the healthy controls (n = 7) were 14.58 ± 0.80 y old (p = 0.058). Cine loops of the CCA B-mode data were digitally recorded, and the arterial elastic modulus was estimated a posteriori with ImBioMark. IMT of the CCA was automatically calculated using QLAB software (Philips, Andover, MA, USA). All patients had been evaluated in utero in our fetal echocardiographic laboratory. ImBioMark detected a significant increase in CCA stiffness in patients with IUGR as compared with healthy controls: elastic modulus = 90.74 ± 11.86 versus 61.30 ± 15.94 kPa, respectively (p = 0.002). There was, however, no significant difference between patients with IUGR and controls in IMT (0.483 ± 0.067 versus 0.476 ± 0.051 mm, respectively, p = 0.831). The impact of IUGR on CCA wall dynamics was confirmed by ImBioMark. The apparent limitation of IMT measurement in this cohort may be the result of geometric arterial changes, that is, the expected thickening, below the level of detection at this age. As early detection of vascular modulation is essential to early intervention in a population at risk, we now intend to extend ImBioMark to investigate larger pathologic cohorts with various degrees of arteriopathy.

Background The long-term sequelae of Kawasaki disease (KD) are based on the coronary complications. Because KD causes generalized vasculitis, with documented aneurysms in the femoral, iliac, renal, axillary, and brachial arteries, the aim of this study was to assess the biophysical properties of the aorta (BPA) after KD. The BPA are biometric measurements representing vascular structural and dynamic changes in response to cardiac work. Methods Anthropometric and echocardiographic measurements of the aorta in a series of patients with KD were compared with those of healthy subjects. The BPA were calculated noninvasively by extrapolating previously validated equations that were conceived for invasive measurements. Because BPA vary with body habitus, control subjects were used to normalize BPA parameters for height to compute BPA Z -score equations. Results Between June 2007 and February 2010, BPA were recorded in 57 patients with KD >1 year after the onset of the disease, 45 without and 12 with coronary artery sequelae. The mean intervals between the acute onset of KD and enrollment were 10.0 ± 5.0 and 5.8 ± 4.5 years for patients with and without coronary artery sequelae, respectively ( P = .008). Patients with KD with coronary artery sequelae had significantly altered Z scores of aortic diameter modulation, Peterson's elastic modulus, and β stiffness index ( P = .001–.016). Patients with KD without coronary artery sequelae also exhibited altered elasticity, stiffness, and pulse-wave velocity ( P = .001−.026). Conclusions Altered BPA after KD are detectible despite apparent resolution of acute vasculitis. Future directions toward determining multilevel and multilayer vascular impact, including vascular autonomous homeostasis, require thorough investigation.

Purpose: Mechanical properties of the arteries are essential in assessing cardiovascular diseases. New imaging modalities that allow mapping strain, shear and elasticity distributions within the arterial wall are rapidly evolving. Very recently, our group introduced an iterative optical flow-based elastography method devoted to B-mode data. In this paper, the authors propose an adaptation of the optical flow method to investigate aortic remodeling following Kawasaki disease, an early childhood vasculitis. Namely, displacement and strain of the aortic wall are used to assess aortic stiffness in this human disease model. The authors also introduce a fully developed automatic method to support postprocessing data analysis. Methods: The sequalae of Kawasaki disease on the ascending aorta were examined in children. The pathologic population (n = 4) was 15.00 ± 2.45 years old, while the healthy control population (n = 5) was 13.13 ± 0.18 years old. B-mode data were digitally recorded with commercially available cardiac echocardiography machines. Results: Kawasaki disease had a very significant impact on the aortic stiffness. Indeed, pathologic subjects’ aortic wall strain estimate was significantly lower compared to healthy controls (2.75% ± 0.56% versus 4.24% ± 0.65%, respectively;p < 0.001). Similarly, displacement of the aortic wall was also significantly lower compared to controls (p < 0.001). Conclusions: The potential of the optical flow-based method to quantify aortic wall remodeling in a human disease model was demonstrated. The authors now intend to extend this investigation to a larger pathologic cohort with various degrees of vasculitis severity.

It is widely accepted in many societies that we are all individuals, with our own thoughts and minds, our own abilities, emotions and personalities, our own free will. In the western world our education systems are based on these ideas, as are our theories of education, our psychologies of behaviour, and our day-to-day communications. How else might we think of ourselves and each other? Social constructionists argue, and there is strong support from neuroscience for this, that we create our worlds and our perceptions of our worlds collaboratively. As our technologies of communication develop and become more ubiquitous, it can be helpful to consider how we might theorise their significance in the production of knowledge. What we think about who we are, and about what education is, are discursively produced. These underlying ideas, that we take for granted, have a significant impact on how we approach the use of technologies for teaching and learning, and on how we interpret the interactions that result.

Preeclampsia is the major cause of maternal and fetal mortality/morbidity. Because hypertension is an important risk factor for preeclampsia, we investigated whether hypertensive mice that overexpress human renin and angiotensinogen develop superimposed preeclampsia. Given that the mechanisms underlying this disease are still poorly understood, animal models are of great use for elucidatation. Blood pressure and proteinuria were measured by telemetry and ELISA, respectively. Heart function was evaluated by echocardiography, whereas pathological cardiac hypertrophy–related genes were assessed by real-time PCR. Soluble fms-like tyrosine kinase 1 plasma concentrations were quantitated by ELISA and placental expression by real-time PCR. Transgenic mice develop de novo proteinuria during gestation and marked blood pressure elevation, which are hallmarks of superimposed preeclampsia on chronic hypertension. Abnormal placentation present in these mothers produced a significant decrease in pup and placental weight and was associated with an increased placental expression of soluble fms-like tyrosine kinase 1. We also found heightened circulating levels of this receptor, when adjusted for placental mass, as has been observed in women who suffer from preeclampsia. Cardiac hypertrophy could be observed in the transgenic mice and was exacerbated by gestation. As a result, heart function was significantly decreased, and markers of pathological hypertrophy were increased. Our data, thus, confirm the characterization of a new model of superimposed preeclampsia on chronic hypertension. Because chronically hypertensive women are at risk of developing the pathology, our model reflects a clinical reality and is, thus, an excellent tool to elucidate the molecular mechanisms triggering this disease.

Experimental and simulation studies were conducted to noninvasively characterize abdominal aneurysms with ultrasound (US) elastography before and after endovascular treatment. Twenty three dogs having bilateral aneurysms surgically created on iliac arteries with venous patches were investigated. In a first set of experiments, the feasibility of elastography to differentiate vascular wall elastic properties between the aneurismal neck (healthy region) and the venous patch (pathological region) was evaluated on six dogs. Lower strain values were found in venous patches (p < 0.001). In a second set of experiments, 17 dogs having endovascular repair (EVAR) by stent graft (SG) insertion were examined three months after SG implantation. Angiography, color Doppler US, examination of macroscopic sections and US elastography were used. The value of elastography was validated with the following end points by considering a solid thrombus of a healed aneurysm as a structure with small deformations and a soft thrombus associated with endoleaks as a more deformable tissue: (1) the correlation between the size of healed organized thrombi estimated by elastography and by macroscopic examinations; (2) the correlation between the strain amplitude measured within vessel wall elastograms and the leak size; and (3) agreement on the presence and size of endoleaks as determined by elastography and by combined reference imaging modalities (angiography + Doppler US). Mean surfaces of solid thrombi estimated with elastography were found correlated with those measured on macroscopic sections (r = 0.88, p < 0.001). Quantitative strain values measured within the vessel wall were poorly linked with the leak size (r = 0.12, p = 0.5). However, the qualitative evaluation of leak size in the aneurismal sac was very good, with a Kappa agreement coefficient of 0.79 between elastography and combined reference imaging modalities. In summary, complementing B-scan and color Doppler, noninvasive US elastography was found to be potentially a relevant tool for aneurismal follow-up after EVAR, provided it allows geometrical and mechanical characterizations of the solid thrombus within the aneurismal sac. This elasticity imaging technique might help detecting potential complications during follows-up subsequent to EVAR.

Background: Noninvasive vascular ultrasoundelastography (NIVE) was recently introduced to assess mechanical properties (strain or elasticity) of peripheral vessel walls. The goal of this study was to determine strain values in subjects with normal carotid arteries and the reproducibility of these measurements. Methods: Sixteen individuals without previous history of carotid atherosclerosis were recruited in four age categories [40–49], [50–59], [60–69], and [70–79] years old. The left and right common and internal carotids (LCC, LIC, RCC, and RIC, respectively) were independently scanned by two radiologists (RAD-A and RAD-B). The axial strain elastograms were computed with the Lagrangian speckle model estimator. Results: Supported by Bland–Altman analyses, strain values between LCC and RCC were found similar with a Pearson correlation coefficient ( r ) of 0.83 ( p 0.0001 ) . Equivalently, a good correlation was found between RAD-A and RAD-B for common carotids with r = 0.80 ( p 0.0001 ) . Lower strain values ( p 0.001 ) were measured for male common carotids ( 1.62 ± 0.32 % ) than females ( 2.21 ± 0.76 % ) . Regarding the internal carotid strain measurements, the correlation was lower between RAD-A and RAD-B with r = 0.52 ( p = 0.01 ) , but drastically decreased between LIC and RIC ( r = 0.16 , nonsignificant). Male internal carotid strain estimates ( p = 0.03 ) were lower ( 1.48 ± 0.44 % ) than in females ( 1.84 ± 0.64 % ) . Additionally, male common and internal carotid mean elastic moduli varied from 33–106 kPa, whereas it covered a range of 25–67 kPa for females. Female carotids were more elastic ( 44 ± 17 kPa ) than males ( 58 ± 17 kPa , p 0.001 ) . Conclusion: Strain measurements in common carotids were found reproducible. However, less consistency was observed for the deeper internal carotids. The NIVE imaging method still remains to be validated with pathological cases, but it might provide a unique approach for stroke prevention and characterization of vascular stiffness.

Non-invasive vascular ultrasoundelastography (NIVE) was recently introduced to characterize mechanical properties of carotid arteries for stroke prevention. Using the Lagrangianspeckle model estimator (LSME), the four components of the 2D deformation matrix ( Δ ) , which are the axial strain ( Δ y y ) and shear ( Δ y x ) and the lateral strain ( Δ x x ) and shear ( Δ x y ) , can be computed. This paper overviews four different implementations of the LSME and addresses their reliability. These implementations include two unconstrained (L&M and L&M + ) and one constrained ( ITER c ) iterative algorithms, and one optical flow-based (OF-based) algorithm. The theoretical frameworks were supported by biomechanical simulations of a pathology-free vessel wall and by one single layer vessel-mimicking phantom study. Regarding simulations, the four LSME implementations provided similar biases on axial motion parameters, except the L&M that outperformed other methods with a minimum strain bias of −3%. LSME axial motion estimates showed good consistence with theory, namely the OF-based algorithm that in a specific instance estimated Δ yy with no relative error on the standard deviation. With regards to lateral motion parameters, ITER c exhibited a minimum strain bias of −8.5% when ultrasound beam and motion mostly run parallel, whereas L&M performs strain and shear estimates with less than 23% bias independently of orientations. The in vitro vessel phantom data showed LSME Δ y y and Δ y x maps that were qualitatively equivalent to theory, and noisy Δ x x and Δ x y elastograms. In summary, the authors propose to promote the OF-based LSME as an optimal choice for further applications of NIVE, because of its reliability to compute both axial strain and shear motion parameters and because it outperformed the other implementations by a factor of 30 or more in terms of processing time.

Plaque rupture is correlated with the plaque morphology, composition, mechanical properties, and with the blood pressure. Whereas the geometry can accurately be assessed with intravascular ultrasound (IVUS) imaging, intravascular elastography (IVE) is capable of extracting information on the plaque local mechanical properties and composition. This paper reports additional IVE validation data regarding reproducibility and potential to characterize atherosclerotic plaques and mural thrombi. In a first investigation, radio frequency (RF) data were acquired from the abdominal aorta of an atherosclerotic rabbit model. In a second investigation, IVUS RF data were recorded from the left coronary artery of a patient referred for angioplasty. In both cases, Galaxy IVUS scanners (Boston Scientific, Freemont, CA), equipped with 40 MHz Atlantis catheters, were used. Elastograms were computed using two methods, the Lagrangian speckle model estimator (LSME) and the scaling factor estimator (SFE). Corroborated with histology, the LSME and the SFE both clearly detected a soft thrombus attached to the vascular wall. Moreover, shear elastograms, only available with the LSME, confirmed the presence of the thrombus. Additionally, IVE was found reproducible with consistent elastograms between cardiac cycles (CCs). Regarding the human dataset, only the LSME was capable of identifying a plaque that presumably sheltered a lipid core. Whereas such an assumption could not be certified with histology, radial shear and tangential strain LSME elastograms enabled the same conclusion. It is worth emphasizing that this paper reports the first ever in vivo tangential strain elastogram with regards to vascular imaging, due to the LSME. It is concluded that the IVE was reproducible exhibiting consistent strain patterns between CCs. The IVE might provide a unique tool to assess coronary wall lesions.

Only a minority of patients with carotid arterial disease have warning symptoms, because the majority of strokes are caused by previously asymptomatic lesions. Because morbidity and mortality after acute stroke are high, patients should be diagnosed and treated before symptoms develop. The hypothesis of this study is that vascular elasticity maps (or elastograms) of carotids are of predictive value for plaque characterization. The strain tensor from either cross-sectional or longitudinal ultrasound radiofrequency data were assessed by a new implementation of the Lagrangian speckle model estimator (LSME), which considers local echogenicity variations. A 26-year-old healthy male (HS1), a 40-year-old (HS2) normal female subject and two 75-year-old asymptomatic patients with severe carotid stenoses were scanned. Reproducible elastograms were obtained as a function of time over five to seven cardiac cycles. Stress-strain modulus elastograms were computed for normal subjects. Stiffening of healthy carotid walls was estimated to be 148 +/- 7 kPa and 163 +/- 30 kPa at peak-systole for HS1 and HS2, respectively. For patients with heterogeneous plaques, strain and shear elastograms revealed interesting information about plaque size, tissue composition and mechanical interaction between structures. In conclusion, the LSME provides a promising approach for strain and shear estimates to characterize vulnerable plaque.

Tissue-mimicking phantoms are very useful in the field of tissue characterization and essential in elastography for the purpose of validating motion estimators. This study is dedicated to the characterization of polyvinyl alcohol cryogel (PVA-C) for these types of applications. A strict fabrication procedure was defined to optimize the reproducibility of phantoms having a similar elasticity. Following mechanical stretching tests, the phantoms were used to compare the accuracy of four different elastography methods. The four methods were based on a one-dimensional (1-D) scaling factor estimation, on two different implementations of a 2-D Lagrangian speckle model estimator (quasistatic elastography methods), and on a 1-D shear wave transient elastography technique (dynamic method). Young's modulus was investigated as a function of the number of freeze-thaw cycles of PVA-C, and of the concentration of acoustic scatterers. Other mechanical and acoustic parameters, such as the speed of sound, shear wave velocity, mass density, and Poisson's ratio, also were assessed. The Poisson's ratio was estimated with good precision at 0.499 for all samples, and the Young's moduli varied in a range of 20 kPa for one freeze-thaw cycle to 600 kPa for 10 cycles. Nevertheless, above six freeze-thaw cycles, the results were less reliable because of sample geometry artifacts. However, for the samples that underwent less than seven freeze-thaw cycles, the Young's moduli estimated with the four elastography methods showed good matching with the mechanical tensile tests with a regression coefficient varying from 0.97 to 1.07, and correlations R2 varying from 0.93 to 0.99, depending on the method

Background: It is uncertain whether Kawasaki disease (KD) increases overall long term cardiovascular risk, especially in those without demonstrable coronary artery lesions. Data from non-invasive vascular assessment, extrapolated from studies of subclinical atherosclerosis, are conflicting. Methods: Patients at least 2 years post-KD and healthy controls had fasting plasma glucose, lipid profile, high sensitivity C-reactive protein, carotid-femoral pulse wave velocity (PWV), carotid intima-media thickness (cIMT), abdominal aorta intima-media thickness (aIMT), retinal vascular calibre, carotid and aortic elastography performed. Results: 37 controls and 45 patients with KD (21 with regressed or persistent coronary artery changes) were studied at mean ± sd of 10.5 ± 5.7 years following KD. Compared to controls, KD patients did not have increased traditional cardiovascular risk factors; blood pressure, body mass index, waist-to-hip ratio, glucose, cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, triglyceride and smoking history. Of the cohort, 26 patients (age 15.38 ± 6.19 years) and 27 controls (age 18.7 ± 7.11 years) have had cIMT, aIMT and carotid elastography analysed. The maximum aIMT in KD patients was 0.65 ± 0.15 mm, compared to 0.63 ± 0.13 mm in controls, with the most marked difference in those with coronary artery changes at 0.68 ± 0.14 mm. After adjusting for age, sex, systolic blood pressure, aortic diastolic diameter and high sensitivity C- reactive protein, the average maximum aIMT in all KD patients was 0.071mm larger (95% CI -0.005, 0.147) than controls. Aortic elastography and Doppler pulse wave analysis are underway. Otherwise, there are no detectible differences in PWV, cIMT, carotid elastography, or retinal vascular calibre between KD patients and controls. Conclusion: Compared to carotid artery characteristics, changes in the abdominal aorta may be more discriminative markers of long-term cardiovascular risk in KD. Focus on large arteries in longitudinal KD vascular studies are warranted. Recruitment and analysis are ongoing and further results will be presented.

Background: Measuring carotid strain is a noninvasive way to assess the mechanical properties of the arterial wall. Whether there is an association between carotid strain and coronary artery status after Kawasaki disease (KD) is unknown. Methods: We enrolled 82 young adults, ages 15 to 30 yrs, with a history of KD (58% male), as well as 16 healthy controls (HC) of similar age (56% male). Carotid wall strain was measured from cine loops of common carotid artery B-mode ultrasound data using an offline optical flow analysis algorithm. Strain was normalized for age (Z-score) using a regression equation derived from a separate series of healthy young adults. Subjects were categorized based on their worst coronary artery status (normal, transiently dilated, aneurysm). Results: The mean age of KD subjects and HC at the time of carotid measurements was 25 ± 8 and 28 ± 8 years, respectively (p=0.30). Mean time since onset of KD was 20 ± 8 yrs. KD subjects with transiently dilated coronary arteries had significantly higher carotid strain compared to those with normal coronaries (p=0.002) and to HC (p=0.01) (Figure); those with CAA had a nonsignificant trend toward lower carotid strain compared to other groups. KD subjects with normal coronaries had carotid strain similar to HC. Conclusion: Young adults with a history of KD with normal coronary arteries also have normal carotid artery strain. Individuals with a history of transiently dilated coronary arteries had a paradoxical trend toward higher carotid strain. Thus, KD patients whose dilated coronary arteries return to normal may have healthier vasculature compared to other KD patients. The significance of this finding merits further study.

Background: Mechanical properties of coronary arteries (CA) hold clues to vascular health and viability. Traditionally assessed with intracoronary imaging, we present an angiography-based system to assess CA vasomotion using automatic vessel segmentation and spatio-temporal tracking. Elastic moduli computed from dynamic CA calibers are compared between non-KD patients (CTL), KD patients with no CA aneurysms (KDAN-), and those with aneurysms (KDAN+). Methods: Proximal CA angiograms are automatically segmented and tracked over a cardiac cycle. CA centerline is extracted and the mean caliber is computed from diameters along its length. The resulting caliber variation reflects the CA vasomotion (Figure 1a). We then calculated the Vasomotion Standard Deviation (VSD) and CA recoil with the mean constriction velocity (MCV). Finally, Elastic Pressure moduli were computed using trans-myocardium pressure gradients. Results: We analyzed 51 left CA segments from 23 patients (5 CTL, 5 KDAN-, 13 KDAN+). Data are mean ± SD normalized pixels (npx). VSD was significantly reduced ( p Conclusion: The proposed angiography-based stiffness assessment system shows abnormal CA vascular physiology in our cohort of KD patients. These results concur with previous invasive studies. The potential usability of this system for vascular health assessment could be applied to previously recorded CA angiograms for risk stratification.

International audience; Non-invasive vascular elastography (NIVE) was recently introduced to characterize mechanical properties of superficial arteries. In this paper, the feasibility of NIVE and its applicability in the context of high-frequency ultrasound imaging is investigated. First, experiments were performed in vitro on vessel-mimicking phantoms. Polyvinyl alcohol cryogel was used to create two double-layer vessels with different mechanical properties. In both cases, the stiffness of the inner layer was made softer. Radial stress was applied within the lumen of the phantoms by applying incremental static pressure steps with a column of a flowing mixture of water-glycerol. The vessel phantoms were insonified at 32 MHz with an ultrasound biomicroscope to provide cross-section sequences of radio-frequency (RF) ultrasound data. The Lagrangian speckle model estimator (LSME) was used to assess the two-dimensional-strain tensors, and the composite Von Mises elastograms were computed. A new implementation of the LSME based on the optical flow equations was introduced. Deformation parameters were estimated using an inversion algorithm. For each in vitro experiment, both layers of approximately 1 mm were distinguished. Second, the use of the method for the purpose of studying small vessels (MicroNIVE) in genetically engineered rodents was introduced. Longitudinal scans of the carotid artery were performed at 40 MHz. The in vivo results give confidence in the feasibility of MicroNIVE as a potential tool to non-invasively study the impact of targeted genes on vascular remodelling in rodents.

Pityriasis rubra pilaris (PRP) is a rare idiopathic dermatosis which may be associated with autoimmune diseases, HIV infection, and internal malignancies. Its association with renal diseases is, however, much less recognized. We report a case of PRP with associated membranous nephropathy (MN), which resolved spontaneously with resolution of the dermatosis. This is only the second reported association between PRP and MN of which we are aware. Further reports of such an association will strengthen the evidence for the two conditions being linked and may thereby shed light on the pathogenesis of both PRP and MN.

An advanced setup for vertical electropolishing of superconducting radio-frequency niobium elliptical cavities has been installed at CEA Saclay. Cavities are vertically electropolished with circulating standard HF-${\mathrm{HF}\text{\ensuremath{-}}\mathrm{H}}_{2}{\mathrm{SO}}_{4}$ electrolytes. Parameters such as voltage, cathode shape, acid flow, and temperature have been investigated. A low voltage (between 6 and 10 V depending on the cavity geometry), a high acid flow ($25\text{ }\text{ }\mathrm{L}/\mathrm{min}$), and a low acid temperature ($20\ifmmode^\circ\else\textdegree\fi{}\text{ }\mathrm{C}$) are considered as promising parameters. Such a recipe has been tested on single-cell and nine-cell International Linear Collider (ILC) as well as 704 MHz five-cell Super Proton Linac (SPL) cavities. Single-cell cavities showed similar performances at 1.6 K being either vertically or horizontally electropolished. The applied baking process provides similar benefit. An asymmetric removal is observed with faster removal in the upper half-cells. Multicell cavities (nine-cell ILC and five-cell SPL cavities) exhibit a standard ${Q}_{0}$ value at low and medium accelerating fields though limited by power losses due to field emitted electrons.

BACKGROUND: Metoprolol can improve haemodynamics in chronic heart failure, but survival benefit has not been proven. We investigated whether metoprolol controlled release/extended release (CR/XL) once daily, in addition to standard therapy, would lower mortality in patients with decreased ejection fraction and symptoms of heart failure. METHODS: We enrolled 3991 patients with chronic heart failure in New York Heart Association (NYHA) functional class II-IV and with ejection fraction of 0.40 or less, stabilised with optimum standard therapy, in a double-blind randomised controlled study. Randomisation was preceded by a 2-week single-blind placebo run-in period. 1990 patients were randomly assigned metoprolol CR/XL 12.5 mg (NYHA III-IV) or 25.0 mg once daily (NYHA II) and 2001 were assigned placebo. The target dose was 200 mg once daily and doses were up-titrated over 8 weeks. Our primary endpoint was all-cause mortality, analysed by intention to treat. FINDINGS: The study was stopped early on the recommendation of the independent safety committee. Mean follow-up time was 1 year. All-cause mortality was lower in the metoprolol CR/XL group than in the placebo group (145 [7.2%, per patient-year of follow-up]) vs 217 deaths [11.0%], relative risk 0.66 [95% CI 0.53-0.81]; p=0.00009 or adjusted for interim analyses p=0.0062). There were fewer sudden deaths in the metoprolol CR/XL group than in the placebo group (79 vs 132, 0.59 [0.45-0.78]; p=0.0002) and deaths from worsening heart failure (30 vs 58, 0.51 [0.33-0.79]; p=0.0023). INTERPRETATION: Metoprolol CR/XL once daily in addition to optimum standard therapy improved survival. The drug was well tolerated.