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Single-molecule force spectroscopy (SMFS) techniques play a pivotal role in unraveling the mechanics and conformational transitions of biological macromolecules under external forces. Among these techniques, multiplexed magnetic tweezers (MT) are particularly well suited to probe very small forces, ≤1 pN, critical for studying noncovalent interactions and regulatory conformational changes at the single-molecule level. However, to apply and measure such small forces, a reliable and accurate force-calibration procedure is crucial. Here, we introduce a new approach to calibrate MT based on thermal motion using the Hadamard variance (HV). To test our method, we perform bead-tether Brownian dynamics simulations that mimic our experimental system and compare the performance of the HV method against two established techniques: power spectral density (PSD) and Allan variance (AV) analyses. Our analysis includes an assessment of each method's ability to mitigate common sources of additive noise, such as white and pink noise, as well as drift, which often complicate experimental data analysis. We find that the HV method exhibits overall similar or higher precision and accuracy, yielding lower force estimation errors across a wide range of signal-to-noise ratios (SNRs) and drift speeds compared with the PSD and AV methods. Notably, the HV method remains robust against drift, maintaining consistent uncertainty levels across the entire studied SNR and drift speed spectrum. We also explore the HV method using experimental MT data, where we find overall smaller force estimation errors compared with PSD and AV approaches. Overall, the HV method offers a robust method for achieving sub-pN resolution and precision in multiplexed MT measurements. Its potential extends to other SMFS techniques, presenting exciting opportunities for advancing our understanding of mechanosensitivity and force generation in biological systems. To make our methods widely accessible to the research commu

Because of their aperiodic nature, quasicrystals are one of the least understood phases in statistical physics. One significant complication they present in comparison to their periodic counterparts is the fact that any quasicrystal can be realized as an exponentially large number of different tilings, resulting in a significant contribution to the quasicrystal entropy. Here, we use free-energy calculations to demonstrate that it is this configurational entropy which stabilizes a dodecagonal quasicrystal in a binary mixture of hard spheres on a plane. Our calculations also allow us to quantitatively confirm that in this system all tiling realizations are essentially equally likely, with free-energy differences less than 0.0001kBT per particle - an observation that could be related to the observation of only random tilings in soft-matter quasicrystals. Owing to the simplicity of the model and its available counterparts in colloidal experiments, we believe that this system is an excellent candidate to achieve the long-awaited quasicrystal self-assembly on the micron scale.

Les propriétés écologiques du bois comparativement à celles des autres matériaux tel que le béton et l’acier font en sorte que son utilisation dans les bâtiments devient de plus en plus essentielle. La conception d’un bâtiment est une activité multidisciplinaire. Dans cette optique, il est important de connaître les enjeux de chaque discipline ainsi que de définir la collaboration nécessaire sur ces bâtiments ayant des particularités différentes. La préfabrication est un processus dans lequel des parties du bâtiment sont fabriquées en usine puis acheminées via un transporteur au chantier. Ce type de construction a de nombreux avantages et pourrait être utilisé davantage au Québec si les intervenants apprennent comment bien l’aborder. Ce projet de recherche vise à étudier l’interaction entre l’architecture, le génie industriel et le génie civil dans la conception d’un bâtiment en bois. Plus précisément, il s’agit d’une étude de cas sur le Club Med de Charlevoix afin de voir comment il aurait pu être réalisé en bois massif ainsi qu’en préfabrication de modules volumétriques. Le contenu présenté dans ce mémoire par article met en évidence les considérations de trois disciplines pour la conception d’alternatives en bois du complexe hôtelier du Club Med de Charlevoix en bois préfabriqué. Un des objectifs est de permettre à l’industrie d’utiliser les conclusions générales obtenues afin de les guider lors de de la conception de futurs bâtiments puisque le projet de maîtrise fait partie d’une chaire industrielle de recherche. Le coeur du mémoire est un article publié dans la revue MDPI Building le 19 avril 2023. Le projet faisant partie de la chaire industrielle de recherche sur les bâtiments écoresponsables en bois, il était également important de satisfaire les attentes du partenaire industriel Cima+. Une analyse de cycle de vie sur l’aspect de la construction est également réalisée afin de comparer les trois scénarios (béton, bois massif et préfabrication en bois).

Background and Objective: Indwelling pleural catheter (IPC) and indwelling peritoneal catheter (IPeC) have established roles in the management of malignant pleural and peritoneal effusions but catheter-related infections remain a major concern. Topical mupirocin prophylaxis has been shown to reduce peritoneal dialysis catheter infections. This study aimed to assess the (i) compatibility of IPC with mupirocin and (ii) feasibility, tolerability and compliance of topical mupirocin prophylaxis in patients with an IPC or IPeC. Methods: (i) Three preparations of mupirocin were applied onto segments of IPC thrice weekly and examined with scanning electron microscope (SEM) at different time intervals. (ii) Consecutive patients fitted with IPC or IPeC were given topical mupirocin prophylaxis to apply to the catheter exit-site following every drainage/dressing change (at least twice weekly) and followed up for 6 months. Results: (i) No detectable structural catheter damage was found with mupirocin applied for up to 6 months. (ii) Fifty indwelling catheters were inserted in 48 patients for malignant pleural (n = 41) and peritoneal (n = 9) effusions. Median follow-up was 121 [median, IQR 19–181] days. All patients tolerated mupirocin well; one patient reported short-term local tenderness. Compliance was excellent with 95.8% of the 989 scheduled doses delivered. Six patients developed catheter-related pleural (n = 3), concurrent peritoneal/local (n = 1) and skin/tract (n = 2) infections from Streptococcus mitis (with Bacillus species or anaerobes), Staphylococcus aureus, Klebsiella pneumoniae and Pseudomonas aeruginosa. Conclusion: This first study of long-term prevention of IPC- or IPeC-related infections found topical mupirocin prophylaxis feasible and well tolerated. Its efficacy warrants future randomized studies.

The stellar initial mass function (IMF) describes the distribution of stellar masses that form in a given star-formation event. The long main-sequence lifetimes of low-mass stars mean that the IMF in this regime (below $\sim~1~\rm{M}_\odot$) can be investigated through star counts. Ultra-faint dwarf galaxies are low luminosity systems with ancient, metal poor stellar populations. We investigate the low-mass IMF in four such systems (Reticulum II, Ursa Major II, Triangulum II, and Segue 1), using Hubble Space Telescope imaging data that reaches to $\lesssim~0.2~\rm{M}_\odot$ in each galaxy. The analysis techniques that we adopt depend on the number of low-mass stars in each sample. We use Kolmogorov-Smirnov tests for all four galaxies to determine whether their observed apparent magnitude distributions can reject a given combination of IMF parameters and binary fraction for the underlying population. We forward model a thousand synthetic populations for each combination of parameters, and reject those parameters only if each of the thousand realizations reject the null hypothesis. We find that all four galaxies reject a variety of IMFs, and the IMFs that they cannot reject include those that are identical, or similar, to that of the stellar populations of the Milky Way. We determine the best-fit parameter values for the IMF in Reticulum II and Ursa Major II and find that the IMF in Reticulum II is generally consistent with that of the Milky Way, while the IMF in Ursa Major II is more bottom-heavy. The interpretation of the results for Ursa Major II is complicated by possible contamination from two known background galaxy clusters., Comment: Accepted to ApJ

We analyze the outer regions of M33, beyond 15 kpc in projected distance from its center using Subaru/HSC multi-color imaging. We identify Red Giant Branch (RGB) stars and Red Clump (RC) stars using the surface gravity sensitive $NB515$ filter for the RGB sample, and a multi-color selection for both samples. We construct the radial surface density profile of these RGB and RC stars, and find that M33 has an extended stellar population with a shallow power-law index of $\alpha > -3$. This result represents a flatter profile than the stellar halo which has been detected by the previous study focusing on the central region, suggesting that M33 may have a double-structured halo component, i.e. inner/outer halos or a very extended disk. Also, the slope of this extended component is shallower than those typically found for halos in large galaxies, implying intermediate-mass galaxies may have different formation mechanisms (e.g., tidal interaction) from large spirals. We also analyze the radial color profile of RC/RGB stars, and detect a radial gradient, consistent with the presence of an old and/or metal-poor population in the outer region of M33, thereby supporting our proposal that the stellar halo extends beyond 15 kpc. Finally, we estimate that the surface brightness of this extended component is $\mu_{\it V} = 35.72 \pm 0.08$ mag arcsec$^{-2}$. If our detected component is the stellar halo, this estimated value is consistent with the detection limit of previous observations., Comment: 17 pages, 15 figures, 2 tables, submitted to ApJ

The second data release of ESA's $Gaia$ mission revealed numerous signatures of disequilibrium in the Milky Way's disc. These signatures are seen in the planar kinematics of stars, which manifest as ridges and ripples in $R-v_{\phi}$, and in vertical kinematics, where a prominent spiral is seen in the $z-v_z$ phase space. In this work, we show an equivalent $\Delta R-v_{\mathrm{R}}$ phase spiral forms following a perturbation to the disc. We demonstrate the behaviour of the $\Delta R-v_{\mathrm{R}}$ phase spirals in both a toy model and a high resolution $N$-body simulation of a satellite interaction. We then confront these models with the data, where we find partial $\Delta R-v_{\mathrm{R}}$ phase spirals in the Solar neighborhood using the most recent data from $Gaia$ DR3. This structure indicates ongoing radial phase mixing in the Galactic disc, suggesting a history of recent perturbations, either through internal or external (e.g., satellite) processes. Future work modelling the $z-v_z$ and $\Delta R-v_{\mathrm{R}}$ phase spirals in tandem may help break degeneracy's between possible origins of the perturbation., Comment: 13 pages, 10 figures, published in MNRAS

We analyse the M31 halo and its substructure within a projected radius of 120 kpc using a combination of Subaru/HSC NB515 and CFHT/MegaCam g- & i-bands. We succeed in separating M31's halo stars from foreground contamination with $\sim$ 90 \% accuracy by using the surface gravity sensitive NB515 filter. Based on the selected M31 halo stars, we discover three new substructures, which associate with the Giant Southern Stream (GSS) based on their photometric metallicity estimates. We also produce the distance and photometric metallicity estimates for the known substructures. While these quantities for the GSS are reproduced in our study, we find that the North-Western stream shows a steeper distance gradient than found in an earlier study, suggesting that it is likely to have formed in an orbit closer to the Milky Way. For two streams in the eastern halo (Stream C and D), we identify distance gradients that had not been resolved. Finally, we investigate the global halo photometric metallicity distribution and surface brightness profile using the NB515-selected halo stars. We find that the surface brightness of the metal-poor and metal-rich halo populations, and the all population can be fitted to a power-law profile with an index of $\alpha = -1.65 \pm 0.02$, $-2.82\pm0.01$, and $-2.44\pm0.01$, respectively. In contrast to the relative smoothness of the halo profile, its photometric metallicity distribution appears to be spatially non-uniform with nonmonotonic trends with radius, suggesting that the halo population had insufficient time to dynamically homogenize the accreted populations., Comment: 24 pages, 26 figures, 5 tables, submitted to MNRAS

One of the most intriguing features of glassy fluids is their heterogeneous dynamics: the system spontaneously forms areas of fast and slow moving particles. Recent research has shown that local structure can be used as a powerful predictor for future dynamics when combined with machine learning techniques. In this thesis we examine the relation between local structure and the dynamical heterogeneity in a glassy system consisting of spheres of two different sizes. We measure the dynamics of this system using event-driven molecular dynamics simulations, and train machine learning techniques to make predictions about these dynamics. We begin the thesis by comparing three machine learning techniques, namely linear regression, neural networks and graph neural networks, that are trained to predict the dynamic propensity based on the same set of parameters that capture the local structure of a particle’s environment. We conclude that linear regression is the preferred method, since it is fast, robust and not sensitive to overfitting. Thereafter, we examine several methods to improve the propensity prediction made by linear regression. The most significant improvement is obtained by providing the algorithm with information about the center of the cage that is formed by neighbouring particles and that acts as a temporary trap for each particle. Providing the linear regression algorithm with this cage center information, leads to impressive improvements in the accuracy of the propensity prediction at times associated with the caging regime. Additionally, we examine the anisotropy in the movements of particles. We find that both collective local drift and preferential directions in cage escape are sources for directionality in the dynamic propensity. Finally, we examine the dynamics of particles in the context of the slow and fast moving regions. We observe that at time scales close to the relaxation time, fast particles preferentially move parallel to the boundary between fa

The interplay between crystal nucleation and the structure of the metastable fluid has been a topic of significant debate over recent years. In particular, it has been suggested that even in simple model systems such as hard or charged colloids, crystal nucleation might be foreshadowed by significant fluctuations in local structure around the location where the nucleus first arises. We investigate this using computer simulations of spontaneous nucleation events in both hard and charged colloidal systems. To detect local structural variations, we use both standard and unsupervised machine learning methods capable of finding hidden structures in the metastable fluid phase. We track numerous nucleation events for the face-centered cubic and body-centered cubic crystals on a local level and demonstrate that all signs of crystallinity emerge simultaneously from the very start of the nucleation process. We thus conclude that we observe no precursor for the crystal nucleation of hard and charged colloids.

Hard spheres are one of the most fundamental model systems in soft matter physics, and have been instrumental in shedding light on nearly every aspect of classical condensed matter. Here, we add one more important phase to the list that hard spheres form: quasicrystals. Specifically, we use simulations to show that an extremely simple, purely entropic model system, consisting of two sizes of hard spheres resting on a flat plane, can spontaneously self-assemble into two distinct random-tiling quasicrystal phases. The first quasicrystal is a dodecagonal square-triangle tiling, commonly observed in a large variety of colloidal systems. The second quasicrystal has, to our knowledge, never been observed in either experiments or simulations. It exhibits octagonal symmetry, and consists of three types of tiles: triangles, small squares, and large squares, whose relative concentration can be continuously varied by tuning the number of smaller spheres present in the system. The observed tile composition of the self-assembled quasicrystals agrees very well with the theoretical prediction we obtain by considering the four-dimensional (lifted) representation of the quasicrystal. Both quasicrystal phases form reliably and rapidly over a significant part of parameter space. Our results demonstrate that entropy combined with a set of geometrically compatible, densely packed tiles can be sufficient ingredients for the self-assembly of colloidal quasicrystals.

The relationship between structure and dynamics in glassy fluids remains an intriguing open question. Recent work has shown impressive advances in our ability to predict local dynamics using structural features, most notably due to the use of advanced machine learning techniques. Here, we explore whether a simple linear regression algorithm combined with intelligently chosen structural order parameters can reach the accuracy of the current, most advanced machine learning approaches for predicting dynamic propensity. To achieve this, we introduce a method to pinpoint the cage state of the initial configuration - i.e., the configuration consisting of the average particle positions when particle rearrangement is forbidden. We find that, in comparison to both the initial state and the inherent state, the structure of the cage state is highly predictive of the long-time dynamics of the system. Moreover, by combining the cage state information with the initial state, we are able to predict dynamic propensities with unprecedentedly high accuracy over a broad regime of time scales, including the caging regime.

BACKGROUND: Impaired respiratory function remains underrecognized in patients with type 2 diabetes (T2D), despite common pulmonary impairment. Meanwhile, there is little data available on the respiratory effects of sodium glucose cotransporter 2 inhibitors (SGLT2i). Hence, we examined the association between SGLT2i use and the risk of adverse respiratory events in a real-world setting. METHODS: We conducted a population-based, nationwide cohort study using an active-comparator new-user design and nationwide claims data of South Korea from January 2015 to December 2020. Among individuals aged 18 years or older, propensity score matching was done to match each new user of SGLT2is with dipeptidyl peptidase 4 inhibitors (DPP4is), with patients followed up according to an as-treated definition. The primary outcome was respiratory events, a composite endpoint of acute pulmonary edema, acute respiratory distress syndrome (ARDS), pneumonia, and respiratory failure. Secondary outcomes were the individual components of the primary outcome and in-hospital death. Cox models were used to estimate hazard ratios (HRs) and 95% CIs. RESULTS: Of 205,534 patient pairs in the propensity score matched cohort, the mean age of the entire cohort was 53.8 years and 59% were men, with a median follow-up of 0.66 years; all baseline covariates achieved balance between the two groups. Incidence rates for overall respiratory events were 4.54 and 7.54 per 1000 person-years among SGLT2i and DPP4i users, respectively, corresponding to a rate difference of 3 less events per 1000 person-years (95% CI - 3.44 to - 2.55). HRs (95% CIs) were 0.60 (0.55 to 0.64) for the composite respiratory endpoint, 0.35 (0.23 to 0.55) for acute pulmonary edema, 0.44 (0.18 to 1.05) for ARDS, 0.61 (0.56 to 0.66) for pneumonia, 0.49 (0.31 to 0.76) for respiratory failure, and 0.46 (0.41 to 0.51) for in-hospital death. Similar trends were found across individual SGLT2is, subgroup analyses of age, sex, history of comorbidit

Background: Since 1991, The Common Rule has provided regulation to protect humans participating in biomedical or social research.1 Despite clear protocols to obtain informed consent from adults, there is limited information on how to incorporate developmental factors such as simplified language, formative assessment, and feedback into youth assent practices. Adolescence, an important period for developing behaviors that impact health throughout the lifespan, is also a time when developmental capabilities vary greatly among peers of the same chronological age. Meaningfully engaging youth in research begins with an assent that integrates developmental factors and promotes the health literacy of youth. Operationalizing this approach narrows the gap between regulation and research practices. Methods: To quantify the language complexity of two assent templates, 3 trained speech-language pathologists used Language Sample Analysis; the results were compared. To assess the usefulness of incorporating development into assent, a developmental approach to assent was designed. This approach was implemented with a randomized sample of 50 youth participating in the Children And Teens Study (CATS). A data capture system was utilized to present simplified assent language in segments and ask 6 questions assessing comprehension. For individuals with incorrect answers, feedback was provided, and the same question was presented a second time. To incorporate youth priorities, values, and strengths into assent resources, demographics, educational experiences, exposure to racism, and resiliency data were analyzed. To evaluate the feasibility of shifting institutional assent practices, semi-structured interviews were conducted, assessing the importance of assent, understanding of a developmental approach, its acceptability, the practicality of requiring it, and the resources needed for Principal Investigators (PIs), to be successful. To design a toolkit of operational resources, the knowle

The Gemini Planet Imager (GPI) is a high contrast imaging instrument that aims to detect and characterize extrasolar planets. GPI is being upgraded to GPI 2.0, with several subsystems receiving a re-design to improve the instrument's contrast. To enable observations on fainter targets and increase stability on brighter ones, one of the upgrades is to the adaptive optics system. The current Shack-Hartmann wavefront sensor (WFS) is being replaced by a pyramid WFS with an low-noise electron multiplying CCD (EMCCD). EMCCDs are detectors capable of counting single photon events at high speed and high sensitivity. In this work, we characterize the performance of the HN\"u 240 EMCCD from N\"uv\"u Cameras, which was custom-built for GPI 2.0. The HN\"u 240 EMCCD's characteristics make it well suited for extreme AO: it has low dark current ($<$ 0.01 e-/pix/fr), low readout noise (0.1 e-/pix/fr at a gain of 5000), high quantum efficiency ( 90% at wavelengths from 600-800 nm; 70% from 800-900 nm), and fast readout (up to 3000 fps full frame). Here we present test results on the EMCCD's noise contributors, such as the readout noise, pixel-to-pixel variability and CCD bias. We also tested the linearity and EM gain calibration of the detector. All camera tests were conducted before its integration into the GPI 2.0 PWFS system., Comment: 16 pages, 14 figures. Conference Proceedings for AO4ELT7, held in June 2023 in Avignon, France

As our nearest large neighbor, the Andromeda Galaxy provides a unique laboratory for investigating galaxy formation and the distribution and substructure properties of dark matter in a Milky Way-like galaxy. Here, we propose an initial 2-epoch ($\Delta t\approx 5$yr), 2-band Roman survey of the entire halo of Andromeda, covering 500 square degrees, which will detect nearly every red giant star in the halo (10$\sigma$ detection in F146, F062 of 26.5, 26.1AB mag respectively) and yield proper motions to $\sim$25 microarcsec/year (i.e., $\sim$90 km/s) for all stars brighter than F146 $\approx 23.6$ AB mag (i.e., reaching the red clump stars in the Andromeda halo). This survey will yield (through averaging) high-fidelity proper motions for all satellites and compact substructures in the Andromeda halo and will enable statistical searches for clusters in chemo-dynamical space. Adding a third epoch during the extended mission will improve these proper motions by $\sim t^{-1.5}$, to $\approx 11$ km/s, but this requires obtaining the first epoch in Year 1 of Roman operations. In combination with ongoing and imminent spectroscopic campaigns with ground-based telescopes, this Roman survey has the potential to yield full 3-d space motions of $>$100,000 stars in the Andromeda halo, including (by combining individual measurements) robust space motions of its entire globular cluster and most of its dwarf galaxy satellite populations. It will also identify high-velocity stars in Andromeda, providing unique information on the processes that create this population. These data offer a unique opportunity to study the immigration history, halo formation, and underlying dark matter scaffolding of a galaxy other than our own., Comment: Submitted in response to the call for Roman Space Telescope Core Community Survey white papers

The Nancy Grace Roman Space Telescope is capable of delivering an unprecedented all-sky, high-spatial resolution, multi-epoch infrared map to the astronomical community. This opportunity arises in the midst of numerous ground- and space-based surveys that will provide extensive spectroscopy and imaging together covering the entire sky (such as Rubin/LSST, Euclid, UNIONS, SPHEREx, DESI, SDSS-V, GALAH, 4MOST, WEAVE, MOONS, PFS, UVEX, NEO Surveyor, etc.). Roman can uniquely provide uniform high-spatial-resolution (~0.1 arcsec) imaging over the entire sky, vastly expanding the science reach and precision of all of these near-term and future surveys. This imaging will not only enhance other surveys, but also facilitate completely new science. By imaging the full sky over two epochs, Roman can measure the proper motions for stars across the entire Milky Way, probing 100 times fainter than Gaia out to the very edge of the Galaxy. Here, we propose NANCY: a completely public, all-sky survey that will create a high-value legacy dataset benefiting innumerable ongoing and forthcoming studies of the universe. NANCY is a pure expression of Roman's potential: it images the entire sky, at high spatial resolution, in a broad infrared bandpass that collects as many photons as possible. The majority of all ongoing astronomical surveys would benefit from incorporating observations of NANCY into their analyses, whether these surveys focus on nearby stars, the Milky Way, near-field cosmology, or the broader universe., Comment: Submitted to the call for white papers for the Roman Core Community Survey (June 16th, 2023), and to the Bulletin of the AAS

The Galactic dwarf spheroidal galaxies (dSphs) provide valuable insight into dark matter (DM) properties and its role in galaxy formation. Their close proximity enables the measurement of line-of-sight velocities for resolved stars, which allows us to study DM halo structure. However, uncertainties in DM mass profile determination persist due to the degeneracy between DM mass density and velocity dispersion tensor anisotropy. Overcoming this requires large kinematic samples and identification of foreground contamination. With 1.25 deg$^2$ and 2394 fibers, PFS plus pre-imaging with Hyper Suprime Cam will make significant progress in this undertaking., Comment: 6 pages, 3 figures, Accepted for publication in Proceedings of the IAUS 379: Dynamical Masses of Local Group Galaxies, Potsdam, March 20-24, 2023

Many disc galaxies host galactic bars, which exert time-dependent, non-axisymmetric forces that can alter the orbits of stars. There should be both angle and radius-dependence in the resulting radial rearrangement of stars ('radial mixing') due to a bar; we present here novel results and trends through analysis of the joint impact of these factors. We use an N-body simulation to investigate the changes in the radial locations of star particles in a disc after a bar forms by quantifying the change in orbital radii in a series of annuli at different times post bar-formation. We find that the bar induces both azimuth angle- and radius- dependent trends in the median distance that stars have travelled to enter a given annulus. Angle-dependent trends are present at all radii we consider, and the radius-dependent trends roughly divide the disc into three 'zones'. In the inner zone, stars generally originated at larger radii and their orbits evolved inwards. Stars in the outer zone likely originated at smaller radii and their orbits evolved outwards. In the intermediate zone, there is no net inwards or outwards evolution of orbits. We adopt a simple toy model of a radius-dependent initial metallicity gradient and discuss recent observational evidence for angle-dependent stellar metallicity variations in the Milky Way in the context of this model. We briefly comment on the possibility of using observed angle-dependent metallicity trends to learn about the initial metallicity gradient(s) and the radial rearrangement that occurred in the disc., Comment: Published in MNRAS, updated to match final refereed version in which a discussion on external galaxies was added

Le champignon pathogène Sclerotinia sclerotiorum s’attaque à une grande variété d’hôtes, dont la laitue. Cette grande variété d’hôtes limite les méthodes de contrôle et de répression du champignon et donc engendre de grandes pertes économiques chaque année en affectant le rendement et la qualité des plantes agricoles. L'utilisation de fongicides synthétiques pour lutter contre cet agent pathogène devient moins efficace en raison du développement de la résistance de S. sclerotiorum, et c’est pourquoi des méthodes de lutte biologiques plus respectueuses de l’environnement sont recherchées. Les travaux de recherche présentés dans ce mémoire s’intéressent à l’utilisation d’agents de biocontrôle, tels que des Pseudomonas spp. phytobénéfiques, pour lutter contre l’infection de la sclérotiniose chez la laitue. Les Pseudomonas spp. ont plusieurs traits qui les rendent performants en tant qu’agents de biocontrôle, tels que la production d’une multitude de métabolites bioactifs comme des antibiotiques et des lipopeptides. Dans ce projet, nous avons donc sélectionné et caractérisé des souches de Pseudomonas spp. capables d’inhiber la croissance du champignon S. sclerotiorum in vitro (objectif 1), validé leur capacité à inhiber le dévelopement de la scérotiniose en conditions in planta, et identifié des gènes ou groupe de gènes potentiellement impliqués dans le biocontrôle observé (objectif 2). Le premier objectif a permis à d’isoler des souches de Pseudomonas spp. prélevées de champs agricoles sous régie biologique situées dans la région de la Montérégie (Québec, Canada). Ces souches ont ensuite été caractérisées, ce qui a permis de construire une phylogénie grâce au séquençage des génomes des souches les plus performantes. Neuf souches de Pseudomonas spp.ont démontré une forte inhibition in vitro dans des essais de confrontation en double culture. Le séquençage du génome entier de ces souches a révélé leur affiliation à quatre sous-groupes phylogénétiques, à savoir P. corruga

Le présent ouvrage propose de reconsidérer les schémas qui orientent souvent le discours récent sur la filiation et l’héritage à partir d’un cas de figure précis : celui de l’appropriation productive de textes qui appartiennent à une tradition éloignée. Le corpus à l’étude est constitué de romans, de nouvelles et de recueils de poèmes québécois parus entre 1989 et 2011, qui proposent un dialogue intertextuel et/ou hypertextuel avec les œuvres de Thomas Bernhard et de Peter Handke. L’examen attentif d’un tel dialogue entrepris par sept écrivains québécois (Normand de Bellefeuille, Diane-Monique Daviau, Denise Desautels, Nicole Filion, Catherine Mavrikakis, Rober Racine et Yvon Rivard) dévoile que les revers dans la transmission ne consacrent nullement l’empêchement de l’auteur contemporain de se tourner – de manière parfois fulgurante – vers des modèles élus, inattendus. Ici, une telle association à des auteurs du canon littéraire germanophone est interprétée à la lumière du concept d’affiliation, qui évoque une adhésion choisie à des contenus d’héritage, mais par laquelle l’écrivain contemporain ne met pas en péril l’originalité profonde de sa propre démarche. Le concept permet ainsi de décrire le travail d’écrivains contemporains qui ne se contentent pas de développer de réelles formes d’appropriation et/ou de réception productives, mais dont l’entreprise tend à renforcer leur propre signature d’auteur dans le lien qu’elle développe avec un héritage littéraire. Les principes de l’affiliation sont exposés à partir d’une typologie quadripartite qui permet par surcroît de relever des modes d’appropriation du canon au sein de textes contemporains et d’éclairer les inflexions spécifiques qu’adoptent ces modes d’appropriation dès lors qu’il est question d’un héritage issu d’une tradition étrangère.

AIMS: We determined the prevalence of prescription smoking cessation pharmacotherapy (SCP) use after hospitalization for major cardiovascular disease (MCD) among people who smoke and whether this varies by sex. METHODS AND RESULTS: We conducted a population-based cohort study including all people hospitalized in New South Wales, Australia, between July 2013 and December 2018 (2017 for private hospitals) with an MCD diagnosis. For patients who also had a diagnosis of current tobacco use, we used linked pharmaceutical dispensing records to identify prescription SCP dispensings within 90 days post-discharge. We determined the proportion who were dispensed an SCP within 90 days, overall and by type of SCP. We used logistic regression to estimate the odds of females being dispensed an SCP relative to males. Of the 150 758 patients hospitalized for an MCD, 20 162 (13.4%) had a current tobacco use diagnosis, 31% of whom were female. Of these, 11.3% (12.4% of females, 10.9% of males) received prescription SCP within 90 days post-discharge; 3.0% were dispensed varenicline, and 8.3% were dispensed nicotine replacement therapy patches. Females were more likely than males to be dispensed a prescription SCP [odds ratio (OR) 1.16, 95% confidence interval (CI) 1.06-1.27)]; however, this was not maintained after adjusting for potential confounders (adjusted OR 1.04, 95% CI 0.94-1.15). CONCLUSION: Very few females and males who smoke use prescription SCPs after hospitalization for an MCD. The use of varenicline, the SCP with the highest efficacy, was particularly low. This represents a missed opportunity to increase smoking cessation in this high-risk population, thereby reducing their risk of recurrent cardiovascular events.

We study the nucleation of nearly hard charged colloidal particles. We use Monte Carlo simulations in combination with free-energy calculations to accurately predict the phase diagrams of these particles and map them via the freezing density to hard spheres, then we use umbrella sampling to explore the nucleation process. Surprisingly, we find that even very small amounts of charge repulsion can have a significant effect on the phase behavior. Specifically, we find that phase boundaries and nucleation barriers are mostly dependent on the Debye screening length and that even screening lengths as small as 2% of the particle diameter are sufficient to show marked differences in both. This work demonstrates clearly that even mildly charged colloids are not effectively hard spheres.

Plant cell walls are versatile materials that can adopt a wide range of mechanical properties through controlled deposition of cellulose fibrils. Wall integrity requires a sufficiently homogeneous fibril distribution to cope effectively with wall stresses. Additionally, specific conditions, such as the negative pressure in water transporting xylem vessels, may require more complex wall patterns, e.g., bands in protoxylem. The orientation and patterning of cellulose fibrils are guided by dynamic cortical microtubules. New microtubules are predominantly nucleated from parent microtubules causing positive feedback on local microtubule density with the potential to yield highly inhomogeneous patterns. Inhomogeneity indeed appears in all current cortical array simulations that include microtubule-based nucleation, suggesting that plant cells must possess an as-yet unknown balancing mechanism to prevent it. Here, in a combined simulation and experimental approach, we show that a limited local recruitment of nucleation complexes to microtubules can counter the positive feedback, whereas local tubulin depletion cannot. We observe that nucleation complexes preferentially appear at the plasma membrane near microtubules. By incorporating our experimental findings in stochastic simulations, we find that the spatial behavior of nucleation complexes delicately balances the positive feedback, such that differences in local microtubule dynamics—as in developing protoxylem—can quickly turn a homogeneous array into a banded one. Our results provide insight into how the plant cytoskeleton has evolved to meet diverse mechanical requirements and greatly increase the predictive power of computational cell biology studies.

In the quest to understand how structure and dynamics are connected in glasses, a number of machine learning based methods have been developed that predict dynamics in supercooled liquids. These methods include both increasingly complex machine learning techniques and increasingly sophisticated descriptors used to describe the environment around particles. In many cases, both the chosen machine learning technique and choice of structural descriptors are varied simultaneously, making it hard to quantitatively compare the performance of different machine learning approaches. Here, we use three different machine learning algorithms - linear regression, neural networks, and graph neural networks - to predict the dynamic propensity of a glassy binary hard-sphere mixture using as structural input a recursive set of order parameters recently introduced by Boattini et al. [Phys. Rev. Lett. 127, 088007 (2021)]. As we show, when these advanced descriptors are used, all three methods predict the dynamics with nearly equal accuracy. However, the linear regression is orders of magnitude faster to train, making it by far the method of choice.

Colloidal self-assembly-the spontaneous organization of colloids into ordered structures-has been considered key to produce next-generation materials. However, the present-day staggering variety of colloidal building blocks and the limitless number of thermodynamic conditions make a systematic exploration intractable. The true challenge in this field is to turn this logic around and to develop a robust, versatile algorithm to inverse design colloids that self-assemble into a target structure. Here, we introduce a generic inverse design method to efficiently reverse-engineer crystals, quasicrystals, and liquid crystals by targeting their diffraction patterns. Our algorithm relies on the synergetic use of an evolutionary strategy for parameter optimization, and a convolutional neural network as an order parameter, and provides a way forward for the inverse design of experimentally feasible colloidal interactions, specifically optimized to stabilize the desired structure.

For quite some time, people have tried to fundamentally understand the processes in lanthanide-doped nanocrystals (NCs). In these materials, the ionic dopants absorb and emit photons, where the emitted photons have a different energy from the absorbed ones. This is possible due to energy transfer (ET) processes, where (a part of) the energy is transferred from one ion to another. And in order to understand the resulting emitted light, it is of importance to understand these microscopic processes. One of these ET processes is the transfer of all its energy to a neighbouring ion, resulting in an effective diffusion of energy. In this thesis we study this diffusion and other diffusion-like effects in a thin film of NaYF4:Er3+Yb3+ NCs, for which we used simulations, differential equations and experiments. First, we performed Monte Carlo simulations in order to connect the ET rate to an effective diffusion coefficient. From these simulations, we found that the diffusion has a transitioning point with respect to the doping concentration, at lower concentrations the diffusion is isotropic and at higher concentrations the diffusion is anisotropic. Secondly we solved the differential equations for two- and three-level energy diagrams in both space and time in order to connect this diffusion coefficient to an experiment. Here we looked at the spatial distribution of the energy, which broadens due to the effective diffusion. Upon solving these equations, however, we found that are also other processes, that are not diffusion, that can lead to broadening and even narrowing of this energy distribution, which is possible due to non-linear behaviour. To test these results, we performed experiments on tuned NCs, such that we can measure these effects independently. For this we used an experimental setup with a pulsed laser that allows us to measure the spatial intensity distribution of the emitted light. This intensity distribution is linearly dependant on the energy distribution a

This paper presents improved constraints on the low-mass stellar initial mass function (IMF) of the Bo\"otes I (Boo~I) ultrafaint dwarf galaxy, based on our analysis of recent deep imaging from the Hubble Space Telescope. The identification of candidate stellar members of Boo~I in the photometric catalog produced from these data was achieved using a Bayesian approach, informed by complementary archival imaging data for the Hubble Ultra Deep Field. Additionally, the existence of earlier-epoch data for the fields in Boo~I allowed us to derive proper motions for a subset of the sources and thus identify and remove likely Milky Way stars. We were also able to determine the absolute proper motion of Boo~I, and our result is in agreement with, but completely independent of, the measurement(s) by \textit{Gaia}. The best-fitting parameter values of three different forms of the low-mass IMF were then obtained through forward modeling of the color-magnitude data for likely Boo~I member stars within an approximate Bayesian computation Markov chain Monte Carlo algorithm. The best-fitting single power-law IMF slope is $\alpha = -1.95_{-0.28}^{+0.32}$, while the best-fitting broken power-law slopes are $\alpha_1 = -1.67_{-0.57}^{+0.48}$ and $\alpha_2 = -2.57_{-1.04}^{+0.93}$. The best-fitting lognormal characteristic mass and width parameters are $\rm{M}_{\rm{c}} = 0.17_{-0.11}^{+0.05} \cal M_\odot$ and $\sigma=0.49_{-0.20}^{+0.13}$. These broken power-law and lognormal IMF parameters for Boo~I are consistent with published results for the stars within the Milky Way and thus it is plausible that Bo{\"o}tes I and the Milky Way are populated by the same stellar IMF., Comment: 27 pages, 14 figures, 4 tables, 3 appendices. Accepted for publication in ApJ

We present the design of SCALES (Slicer Combined with Array of Lenslets for Exoplanet Spectroscopy) a new 2-5 micron coronagraphic integral field spectrograph under construction for Keck Observatory. SCALES enables low-resolution (R~50) spectroscopy, as well as medium-resolution (R~4,000) spectroscopy with the goal of discovering and characterizing cold exoplanets that are brightest in the thermal infrared. Additionally, SCALES has a 12x12" field-of-view imager that will be used for general adaptive optics science at Keck. We present SCALES's specifications, its science case, its overall design, and simulations of its expected performance. Additionally, we present progress on procuring, fabricating and testing long lead-time components., Comment: 19 pages, 12 Figures, SPIE Astronomical Telescopes + Instrumentation, (#12184-18), 2022, Montreal, Canada

Comment les pays sont-ils gouvernés ? Selon quelles modalités le président des États-Unis, le premier ministre du Royaume-Uni, le président de la France ou le chancelier de l'Allemagne accèdent-ils à leur fonction d'autorité et quelle est la portée réelle de celle-ci dans leur pays respectif ? En quoi consiste le rôle des députés de l'Assemblée populaire de Chine comparativement à celui des députés de l'Inde ? Voilà quelques-unes des questions auxquelles le présent volume s'emploie à répondre. C'est donc sous un angle comparatif que les auteurs de cet ouvrage se proposent d'analyser une sélection significative de régimes politiques. Ainsi, après quelques chapitres qui mettent l'accent sur des notions et des considérations préparatoires portant notamment sur l'émergence de l'État, les types de constitution, la formation des régimes politiques ainsi que les conditions de naissance de la démocratie libérale, le volume présente, à la lumière des éléments conceptuels préalables, les régimes politiques de neuf pays : le Royaume-Uni, les États-Unis, la France, la République fédérale d'Allemagne, la Fédération de Russie, le Brésil, le Nigeria, la République populaire de Chine et la République fédérale de l'Inde. Cette deuxième édition de Régimes politiques et sociétés dans le monde reflète les modifications constitutionnelles et institutionnelles qui ont eu lieu dans les régimes politiques abordés, tout en tenant compte des récents développements historiques, sociologiques, économiques et autres.

Is materialism still relevant to critically think politics? Throughout modernity, the concept of materialism was associated with fatalism and naturalism, when it was not simply dismissed as heresy and atheism. In the nineteenth century, materialism evolved into a central concept of progressive politics, reappearing again in the past decades through renewed Marxist and Spinoza-based approaches, New Materialism, and feminist discourses. This volume inquires these contrasting uses from theoretical and historical perspectives., Abbreviations, Acknowledgments, From ‘Materialism’ towards ‘Materialities’ | THE EDITORS | 1-18, I. THE ACTUALITY OF SPINOZA’S MATERIALISM, Introduction to Part i | STEFAN HAGEMANN | 21-23, Materialist Variations on Spinoza: Theoretical Alliances and Political Strategies | MARIANA DE GAINZA | 25-37, Non Defuit Materia: Freedom and Necessity in Spinoza’s Democratic Theory | STEFANO VISENTIN | 39-54, Temporality and History in Spinoza: The Refusal of Teleological Thought | ERICKA MARIE ITOKAZU | 55-72, Spinozist Moments in Deleuze: Materialism as Immanence | MAURICIO ROCHA | 73-90, Are there One or Two Aleatory Materialisms? | VITTORIO MORFINO | 91-106, II. THE MATERIALITY OF THE MILIEU AND THE MATERIALIST EDUCATION, Introduction to Part ii | MARLENE KIENBERGER AND BRUNO PACE | 109-112, Language Follows Labour: Nikolai Marr’s Materialist Palaeontology of Speech | ELENA VOGMAN | 113-132, Materialism and Capitalism Today: Zoo-aesthetics and a Critique of the Social Bond after Marcel Mauss and André Leroi-Gourhan | CATHERINE PERRET | 133-144, The Product of Circumstances: Towards a Materialist and Situated Pedagogy | MARLON MIGUEL | 145-162, In the Labyrinth of Emancipation: An Inquiry into the Relationship between Knowledge and Politics | BERNARDO BIANCHI | 163-180, A Materialist Education: Thinking with Spinoza | PASCAL SÉVÉRAC | 181-196, III. CRITICAL MATERIALITIES IN FEMINISM AND NEW MATERIALISM, Introduction to Part iii | ALISON SPERLING | 199-202, Materialism, Matter, Matrix, and Mater: Contesting Notions in Feminist and Gender Studies | CORNELIA MÖSER | 203-214, Anarchafeminism & the Ontology of the Transindividual | CHIARA BOTTICI | 215-231, Psychodynamism of Individuation and New Materialism: Possible Encounters | ÉMILIE FILION-DONATO | 233-252, Emergence that Matters and Emergent Irrelevance: On the Political Use of Fundamental Physics | CHRISTOPH F. E. HOLZHEY | 253-268, IV. TOWARDS A RENEWED HISTORICAL MATERIALISM, Introduction to Part iv | DANIEL LIU | 271-276, Materialism against Materialism: Taking up Marx’s Break with Reductionism | FRIEDER OTTO WOLF | 277-292, Materialism, Politics, and the History of Philosophy: French, German, and Turkish Materialist Authors in the Nineteenth Century | AYŞE YUVA | 293-312, The Historicity of Materialism and the Critique of Politics | ALEX DEMIROVIĆ | 313-326, On Populist Illusion: Impasses of Political Ontology, or How the Ordinary Matters | FACUNDO VEGA | 327-343, Theory’s Method? Ethnography and Critical Theory | MARIANNA POYARES | 345-363, References, Notes on the Contributors, Index

Ligand coated nanoparticles are complex objects consisting of a metallic or semiconductor core with organic ligands grafted on their surface. These organic ligands provide stability to a nanoparticle suspension. In solutions, the effective interactions between such nanoparticles are mediated through a complex interplay of interactions between the nanoparticle cores, the surrounding ligands, and the solvent molecules. While it is possible to compute these interactions using fully atomistic molecular simulations, such computations are too expensive for studying self-assembly of a large number of nanoparticles. The problem can be made tractable by removing the degrees of freedom associated with the ligand chains and solvent molecules and using the potentials of mean force (PMF) between nanoparticles. In general, the functional dependence of the PMF on the inter-particle distance is unknown and can be quite complex. In this article, we present a method to model the two-body and three-body PMF between ligand coated nanoparticles through a linear combination of symmetry functions. The method is quite general and can be extended to model interactions between different types of macromolecules.

Predicting the local dynamics of supercooled liquids based purely on local structure is a key challenge in our quest for understanding glassy materials. Recent years have seen an explosion of methods for making such a prediction, often via the application of increasingly complex machine learning techniques. The best predictions so far have involved so-called Graph Neural Networks (GNNs) whose accuracy comes at a cost of models that involve on the order of 105 fit parameters. In this Letter, we propose that the key structural ingredient to the GNN method is its ability to consider not only the local structure around a central particle, but also averaged structural features centered around nearby particles. We demonstrate that this insight can be exploited to design a significantly more efficient model that provides essentially the same predictive power at a fraction of the computational complexity (approximately 1000 fit parameters), and demonstrate its success by fitting the dynamic propensity of Kob-Andersen and binary hard-sphere mixtures. We then use this to make predictions regarding the importance of radial and angular descriptors in the dynamics of both models.

Simulations of colloidal suspensions consisting of mesoscopic particles and smaller species such as ions or depletants are computationally challenging as different length and time scales are involved. Here, we introduce a machine learning (ML) approach in which the degrees of freedom of the microscopic species are integrated out and the mesoscopic particles interact with effective many-body potentials, which we fit as a function of all colloid coordinates with a set of symmetry functions. We apply this approach to a colloid-polymer mixture. Remarkably, the ML potentials can be assumed to be effectively state-independent and can be used in direct-coexistence simulations. We show that our ML method reduces the computational cost by several orders of magnitude compared to a numerical evaluation and accurately describes the phase behavior and structure, even for state points where the effective potential is largely determined by many-body contributions.

In this paper we use computer simulations to examine point defects in systems of "soft"colloidal particles including Hertzian spheres, and star polymers. We use Monte Carlo simulations to determine the deformation of the different crystals associated with vacancies and interstitials and use thermodynamic integration to predict the equilibrium concentrations of such defects. We find that the nature of the lattice distortion is mainly determined by the crystal structure and not by the specifics of the interaction potential. We can distinguish one-, two-, and three-dimensional lattice distortions and find that the range of the distortion generally depends on the dimensionality. We find that in both model systems the deformation of the body-centered cubic (BCC) crystal caused by an interstitial is one-dimensional and we show that its structure is well described as a crowdion. Similarly, we show that the one-dimensional deformation of the hexagonal (H) crystal of Hertzian spheres caused by a vacancy can be characterized as a voidion. Interestingly, with the exception of the FCC crystal in the Hertzian sphere model, in all cases we find that the interstitial concentration is higher than the vacancy concentration. Most noteworthy, the concentration of interstitials in the BCC crystals can reach up to 1%.

Charged colloidal particles—on both the nano and micron scales—have been instrumental in enhancing our understanding of both atomic and colloidal crystals. These systems can be straightforwardly realized in the lab and tuned to self-assemble into body-centered-cubic (BCC) and face-centered-cubic (FCC) crystals. While these crystals will always exhibit a finite number of point defects, including vacancies and interstitials—which can dramatically impact their material properties—their existence is usually ignored in scientific studies. Here, we use computer simulations and free-energy calculations to characterize vacancies and interstitials in FCC and BCC crystals of point-Yukawa particles. We show that, in the BCC phase, defects are surprisingly more common than in the FCC phase, and the interstitials manifest as so-called crowdions: an exotic one-dimensional defect proposed to exist in atomic BCC crystals. Our results open the door to directly observe these elusive defects in the lab.

Importance: Although concerns exist regarding a potential increased risk of cardiovascular events for smoking cessation pharmacotherapies, there is general consensus that any increased risk associated with their use would be outweighed by the benefits of smoking cessation; thus, clinical guidelines recommend that such pharmacotherapies be offered to everyone who wants to quit smoking. In the interest of minimizing risk to patients, prescribers need evidence indicating how these pharmacotherapies compare with one another in terms of cardiovascular safety. Objective: To compare the risk of major adverse cardiovascular events (MACE) among individuals initiating varenicline, nicotine replacement therapy (NRT) patches, or bupropion. Design, Setting, and Participants: This retrospective, population-based cohort study using linked pharmaceutical dispensing, hospital admissions, and death data was conducted in New South Wales, Australia. Participants included adults who were dispensed a prescription smoking cessation pharmacotherapy between 2008 and 2015 or between 2011 and 2015, depending on the availability of the pharmacotherapies being compared. Pairwise comparisons were conducted for risk of MACE among 122932 varenicline vs 92148 NRT initiators; 342064 varenicline vs 10457 bupropion initiators; and 102817 NRT vs 6056 bupropion initiators. Exposure: First course of the smoking cessation pharmacotherapy of interest. Main Outcomes and Measures: The primary outcome was MACE, defined as a composite of acute coronary syndrome, stroke, and cardiovascular death. Secondary outcomes were the individual components of MACE. Inverse probability of treatment weighting with high-dimensional propensity scores was used to account for potential confounding. Cox proportional hazards regression models with robust variance were used to estimate hazard ratios (HRs) and 95% CIs. Data were analyzed January 24, 2019, to September 1, 2021. Results: The mean (SD) age of included individuals rang

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