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Forman et al. (2020+) constructed $(\alpha,\theta)$-interval partition evolutions for $\alpha\in(0,1)$ and $\theta\ge 0$, in which the total sums of interval lengths ("total mass") evolve as squared Bessel processes of dimension $2\theta$, where $\theta\ge 0$ acts as an immigration parameter. These evolutions have pseudo-stationary distributions related to regenerative Poisson--Dirichlet interval partitions. In this paper we study symmetry properties of $(\alpha,\theta)$-interval partition evolutions. Furthermore, we introduce a three-parameter family ${\rm SSIP}^{(\alpha)}(\theta_1,\theta_2)$ of self-similar interval partition evolutions that have separate left and right immigration parameters $\theta_1\ge 0$ and $\theta_2\ge 0$. They also have squared Bessel total mass processes of dimension $2\theta$, where $\theta=\theta_1+\theta_2-\alpha\ge-\alpha$ covers emigration as well as immigration. Under the constraint $\max\{\theta_1,\theta_2\}\ge\alpha$, we prove that an ${\rm SSIP}^{(\alpha)}(\theta_1,\theta_2)$-evolution is pseudo-stationary for a new distribution on interval partitions, whose ranked sequence of lengths has Poisson--Dirichlet distribution with parameters $\alpha$ and $\theta$, but we are unable to cover all parameters without developing a limit theory for composition-valued Markov chains, which we do in a sequel paper., Comment: 22 pages, 3 figures

We introduce and study interval partition diffusions with Poisson--Dirichlet$(\alpha,\theta)$ stationary distribution for parameters $\alpha\in(0,1)$ and $\theta\ge 0$. This extends previous work on the cases $(\alpha,0)$ and $(\alpha,\alpha)$ and builds on our recent work on measure-valued diffusions. Our methods for dealing with general $\theta\ge 0$ allow us to strengthen previous work on the special cases to include initial interval partitions with dust. In contrast to the measure-valued setting, we can show that this extended process is a Feller process improving on the Hunt property established in that setting. These processes can be viewed as diffusions on the boundary of a branching graph of integer compositions. Indeed, by studying their infinitesimal generator on suitable quasi-symmetric functions, we relate them to diffusions obtained as scaling limits of composition-valued up-down chains., Comment: 47 pages, 8 figures. Version 3: some significant additions are made and the introduction is substantially rewritten

In previous work, we constructed Fleming--Viot-type measure-valued diffusions (and diffusions on a space of interval partitions of the unit interval $[0,1]$) that are stationary with the Poisson--Dirichlet laws with parameters $\alpha\in(0,1)$ and $\theta\geq 0$. In this paper, we complete the proof that these processes resolve a conjecture by Feng and Sun (2010) by showing that the processes of ranked atom sizes (or of ranked interval lengths) of these diffusions are members of a two-parameter family of diffusions introduced by Petrov (2009), extending a model by Ethier and Kurtz (1981) in the case $\alpha=0$. The latter diffusions are continuum limits of up-down Chinese restaurant processes., Comment: 20 pages

International audience; Environmental enteric dysfunction (EED) is an elusive, inflammatory syndrome of the small intestine thought to be associated with enterocyte loss and gut leakiness and lead to stunted child growth. To date, the gold standard for diagnosis is small intestine biopsy followed by histology. Several putative biomarkers for EED have been proposed and are widely used in the field. Here, we assessed in a cross-sectional study of children aged 2–5 years for a large set of biomarkers including markers of protein exudation (duodenal and fecal alpha-1-antitrypsin (AAT)), inflammation (duodenal and fecal calprotectin, duodenal, fecal and blood immunoglobulins, blood cytokines, C-reactive protein (CRP)), gut permeability (endocab, lactulose-mannitol ratio), enterocyte mass (citrulline) and general nutritional status (branched-chain amino acids (BCAA), insulin-like growth factor) in a group of 804 children in two Sub-Saharan countries. We correlated these markers with each other and with anemia in stunted and non-stunted children. AAT and calprotectin, CRP and citrulline and citrulline and BCAA correlated with each other. Furthermore, BCAA, citrulline, ferritin, fecal calprotectin and CRP levels were correlated with hemoglobin levels. Our results show that while several of the biomarkers are associated with anemia, there is little correlation between the different biomarkers. Better biomarkers and a better definition of EED are thus urgently needed.

Objective: Obtaining a systematic medical history (MH) from a patient is a core competency in medical education and plays a vital role in the diagnosis of diseases. At the Faculty of Medicine at LMU Munich, students have their first course in MH taking during their second year. Due to the COVID-19 pandemic, the traditional bedside MH taking course had to be transformed into an online course (OC). Our objectives were to implement an online MH taking course, to evaluate its feasibility and to compare the evaluation results to a historic cohort that had undertaken the traditional bedside teaching course (BTC).Methods: 874 second-year students participated in the OC (BTC=827). After teaching the theoretical background via asynchronous online lectures, students participated in a practical exercise with fellow students using the video communication platform Zoom where they were able to practice taking a MH on the basis of fictitious, text-based patient cases. Students were then asked to evaluate the course through a standardized online survey with 31 questions on teaching quality and self-perceived learning success, which had also been used in previous years. The survey results were compared to the results of the historic cohort using the Mann-Whitney U test.Results: A total of n=162 students (18.5%) evaluated the OC. In the historic cohort, n=252 (30.5%) completed the survey. 85.3% of the OC respondents thought that the atmosphere during the practical exercise was productive and 83.0% greatly appreciated the flexibility in terms of time management. Moreover, they appreciated the online resources as well as having the opportunity to undertake a MH taking course during the COVID-19 pandemic. 27.7% of the respondents thought that traditional BTCs should be supplemented through more online activities in the future. With respect to the ability of independently taking a MH upon completion of the course, the OC was rated significantly lower relative to the BTC (mean OC=2.4, SD=±1.1 vs. mean BTC=1.9, SD=±1.1 (1=strongly agree; 5=strongly disagree); p

OBJECTIVES The interference of a transtricuspid cardiac implantable electronic device (CIED) lead with tricuspid valve function may contribute to the mechanism of tricuspid regurgitation (TR) and poses specific therapeutic challenges during transcatheter tricuspid valve intervention (TTVI). Feasibility and efficacy of TTVI in presence of a CIED is unclear. BACKGROUND Feasibility of TTVI in presence of a CIED lead has never been proven on a large basis. METHODS The study population consisted of 470 patients with severe symptomatic TR from the TriValve (Transcatheter Tricuspid Valve Therapies) registry who underwent TTVI at 21 centers between 2015 and 2018. The association of CIED and outcomes were assessed. RESULTS Pre-procedural CIED was present in 121 of 470 (25.7%) patients. The most frequent location of the CIED lead was the posteroseptal commissure (44.0%). As compared with patients without a transvalvular lead (no-CIED group), patients having a tricuspid lead (CIED group) were more symptomatic (New York Heart Association functional class III to IV in 95.9% vs. 92.3%; p = 0.02) and more frequently had previous episodes of right heart failure (87.8% vs. 69.0%; p = 0.002). No-CIED patients had more severe TR (effective regurgitant orifice area 0.7 ± 0.6 cm2 vs. 0.6 ± 0.3 cm2; p = 0.02), but significantly better right ventricular function (tricuspid annular plane systolic excursion = 16.7 ± 5.0 mm vs. 15.9 ± 4.0 mm; p = 0.04). Overall, 373 patients (79%) were treated with the MitraClip (Abbott Vascular, Santa Clara, California) (106 [87.0%] in the CIED group). Among them, 154 (33%) patients had concomitant transcatheter mitral repair (55 [46.0%] in the CIED group, all MitraClip). Procedural success was achieved in 80.0% of no-CIED patients and in 78.6% of CIED patients (p = 0.74), with an in-hospital mortality of 2.9% and 3.7%, respectively (p = 0.70). At 30 days, residual TR ≤2+ was observed in 70.8% of no-CIED and in 73.7% of CIED patients (p = 0.6). Symptomatic improvement was observed in both groups (NYHA functional class I to II at 30 days: 66.0% vs. 65.0%; p = 0.30). Survival at 12 months was 80.7 ± 3.0% in the no-CIED patients and 73.6 ± 5.0% in the CIED patients (p = 0.30). CONCLUSIONS TTVI is feasible in selected patients with CIED leads and acute procedural success and short-term clinical outcomes are comparable to those observed in patients without a transtricuspid lead.

We give a pathwise construction of a two-parameter family of purely-atomic-measure-valued diffusions in which ranked masses of atoms are stationary with the Poisson-Dirichlet$(\alpha,\theta)$ distributions, for $\alpha\in (0,1)$ and $\theta\ge 0$. This resolves a conjecture of Feng and Sun (2010). We build on our previous work on $(\alpha,0)$- and $(\alpha,\alpha)$-interval partition evolutions. Indeed, we first extract a self-similar superprocess from the levels of stable processes whose jumps are decorated with squared Bessel excursions and distinct allelic types. We complete our construction by time-change and normalisation to unit mass. In a companion paper, we show that the ranked masses of the measure-valued processes evolve according to a two-parameter family of diffusions introduced by Petrov (2009), extending work of Ethier and Kurtz (1981). These ranked-mass diffusions arise as continuum limits of up-down Markov chains on Chinese restaurant processes., Comment: 57 pages, 5 figures

In 1990, Bertoin constructed a measure-valued Markov process in the framework of a Bessel process of dimension between 0 and 1. In the present paper, we represent this process in a space of interval partitions. We show that this is a member of a class of interval partition diffusions introduced recently and independently by Forman, Pal, Rizzolo and Winkel using a completely different construction from spectrally positive stable L\'evy processes with index between 1 and 2 and with jumps marked by squared Bessel excursions of a corresponding dimension between $-2$ and 0.

Microbial decomposition of thawed permafrost carbon in thermokarst lakes leads to the release of ancient carbon as the greenhouse gas methane (CH 4), yet potential mitigating processes are not understood. Here, we report δ 13 C-CH 4 signatures in the pore water of a thermokarst lake sediment core that points towards in situ occurrence of anaerobic oxidation of methane (AOM). Analysis of the microbial communities showed a natural enrichment in CH 4-oxidizing archaeal communities that occur in sediment horizons at temperatures near 0 °C. These archaea also showed high rates of AOM in laboratory incubations. Calculation of the stable isotopes suggests that 41 to 83% of in situ dissolved CH 4 is consumed anaerobically. Quantification of functional genes (mcrA) for anaerobic methano-trophic communities revealed up to 6.7±0.7×10 5 copy numbers g −1 wet weight and showed similar abundances to bacterial 16S rRNA gene sequences in the sediment layers with the highest AOM rates. We conclude that these AOM communities are fueled by CH 4 produced from permafrost organic matter degradation in the underlying sediments that represent the radially expanding permafrost thaw front beneath the lake. If these communities are widespread in thermokarst environments, they could have a major mitigating effect on the global CH 4 emissions.

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We provide a new characterisation of Duquesne and Le Gall's $\alpha$-stable tree, $\alpha\in(1,2]$, as the solution of a recursive distribution equation (RDE) of the form $\mathcal{T}\overset{d}{=}g(\xi,\mathcal{T}_i, i\geq0)$, where $g$ is a concatenation operator, $\xi = (\xi_i, i\geq 0)$ a sequence of scaling factors, $\mathcal{T}_i$, $i \geq 0$, and $\mathcal{T}$ are i.i.d. trees independent of $\xi$. This generalises a version of the well-known characterisation of the Brownian Continuum Random Tree due to Aldous, Albenque and Goldschmidt. By relating to previous results on a rather different class of RDE, we explore the present RDE and obtain for a large class of similar RDEs that the fixpoint is unique (up to multiplication by a constant) and attractive., Comment: 30 pages, 5 figures

The rare biosphere, the low abundant microbial populations, is suggested to be a conserved way of microbial life. Here we conducted a molecular survey of rare methanogenic archaea in the environment targeting the mcrA gene in order to test if general concepts associated with the structure of the rare bacterial biosphere also apply to single functional groups. Similar to what is known about rare bacterial communities, the contribution of rare methanogens to the alpha diversity is much larger than to Bray-Curtis measures. Moreover, a similar core group of methanogens harbored by the abundant and rare communities suggests similar sources and environmental controls of both groups. Among the communities of different levels of rarity, the conditionally rare methanogenic taxa largely account for the overall community dynamics of the rare biosphere and likely enter the dominant community under favorable environmental conditions. In addition, we observed a positive correlation between the alpha diversity and the production of methane when the rare taxa were taken into account. This supports the concept that increasing microbial biodiversity enhances ecological function. The composition and environmental associations of the rare methanogenic biosphere allow us to conclude that rarity is a conserved way also for single functional groups., Similar to bacteria, rarity is a conserved way of life also for methanogenic archaea.

Methanogenic archaea are important for the global greenhouse gas budget since they produce methane under anoxic conditions in numerous natural environments such as oceans, estuaries, soils, and lakes. Whether and how environmental change will propagate into methanogenic assemblages of natural environments remains largely unknown owing to a poor understanding of global distribution patterns and environmental drivers of this specific group of microorganisms. In this study, we performed a meta-analysis targeting the biogeographic patterns and environmental controls of methanogenic communities using 94 public mcrA gene datasets. We show a global pattern of methanogenic archaea that is more associated with habitat filtering than with geographical dispersal. We identify salinity as the control on methanogenic community composition at global scale whereas pH and temperature are the major controls in non-saline soils and lakes. The importance of salinity for structuring methanogenic community composition is also reflected in the biogeography of methanogenic lineages and the physiological properties of methanogenic isolates. Linking methanogenic alpha-diversity with reported values of methane emission identifies estuaries as the most diverse methanogenic habitats with, however, minor contribution to the global methane budget. With salinity, temperature and pH our study identifies environmental drivers of methanogenic community composition facing drastic changes in many natural environments at the moment. However, consequences of this for the production of methane remain elusive owing to a lack of studies that combine methane production rate with community analysis.

Detection of methylated free-circulating DNA (mfcDNA) for hyperplastic polyposis 1 (HPP1) in blood is correlated with a poor prognosis for patients with metastatic colorectal cancers (mCRC). Here, we analyzed the plasma levels of HPP1 mfcDNA in mCRC patients treated with a combination therapy containing a fluoropyrimidine, oxaliplatin and bevacizumab to test whether HPP1 mfcDNA is a suitable prognostic and response biomarker. From 467 patients of the prospective clinical study AIO-KRK-0207, mfcDNA was isolated from plasma samples at different time points and bisulfite-treated mfcDNA was quantified using methylation specific PCR. About 337 of 467 patients had detectable levels for HPP1 mfcDNA before start of treatment. The detection was significantly correlated with poorer overall survival (OS) (HR = 1.86; 95%CI 1.37-2.53). About 2-3 weeks after the first administration of combination chemotherapy, HPP1 mfcDNA was reduced to non-detectable levels in 167 of 337 patients. These patients showed a better OS compared with patients with continued detection of HPP1 mfcDNA (HR HPP1(sample 1: pos/ sample 2: neg) vs. HPP1(neg/neg) = 1.41; 95%CI 1.00-2.01, HPP1(neg,pos/pos) vs. HPP1(neg/neg) = 2.60; 95%CI 1.86-3.64). Receiver operating characteristic analysis demonstrated that HPP1 mfcDNA discriminates well between patients who do (not) respond to therapy according to the radiological staging after 12 or 24 weeks (AUC = 0.77 or 0.71, respectively). Detection of HPP1 mfcDNA can be used as a prognostic marker and an early marker for response (as early as 3-4 weeks after start of treatment compared with radiological staging after 12 or 24 weeks) to identify patients who will likely benefit from a combination chemotherapy with bevacizumab. info:eu-repo/semantics/publishedVersion

We study the infinite time shock limits given certain Markovian initial velocities to the inviscid Burgers turbulence. Specifically, we consider the one-sided case where initial velocities are zero on the negative half-line and follow a time-homogeneous nice Markov process X on the positive half-line. Finite shock limits occur if the Markov process is transient tending to infinity. They form a Poisson point process if X is spectrally negative. We give an explicit description when X is furthermore spatially homogeneous (a Lévy process) or a self-similar process on (0, ∞). We also consider the two-sided case where we suppose an independent dual process in the negative spatial direction. Both spatial homogeneity and an exponential Lévy condition lead to stationary shock limits.

De opleiding Bedrijfskunde van de Hogeschool van Arnhem en Nijmegen (HAN) is vorig jaar gestart met het innovatieprogramma ‘Ontdek het beroep. Leren in 3 werelden’. Dit programma, kortweg ‘3 W-leren’, richt zich op de samensmelting van beroepspraktijk, toegepast onderzoek en onderwijs. De focus daarbij is identiteitsontwikkeling en de ontwikkeling van een beroepsgerelateerde kennisbasis, gesteund door werk- en leeromgevingen.

We embed Duquesne and Le Gall's stable tree into a binary compact continuum random tree (CRT) in a way that solves an open problem posed by Goldschmidt and Haas. This CRT can be obtained by applying a recursive construction method of compact CRTs as presented in earlier work to a specific distribution of a random string of beads, i.e. a random interval equipped with a random discrete measure. We also express this CRT as a tree built by replacing all branch points of a stable tree by rescaled i.i.d. copies of a Ford CRT. Some of these developments are carried out in a space of infinity-marked metric spaces generalising Miermont's notion of a k-marked metric space., Comment: 36 pages, 1 figure

We present the software framework EWE, which is designed for coupled electromechanical simulations in computational cardiology. EWE is build on the multi-physics framework MOOSE. Numerical simulations of coupled problems on an idealized geometry for a left ventricle are shown.

In this paper we investigate the conservation of phase space volume of the Boris-SDC algorithm. This method provides a generic way to extend the standard, second-order accurate Lorentz force integrator commonly used for charged particles in an electric and magnetic field to a high-order method using spectral deferred corrections. For a single particle in a Penning trap and different frequencies of the electric and magnetic fields, we assess the conservation properties of the method by computing the update matrix of one step of Boris-SDC as well as its determinant. We compare the results to the convergence regions and relate them to energy conservation properties of the method.

In this dissertation, we propose to study a general notion of a down-up Markov chain for multifurcating trees with n labelled leaves. We study in detail down-up chains associated with the (α, γ)-growth process of Chen et al. (2009), in several different ways. Firstly, in the special case of γ = 1 − α, the stable tree growth process, we generalize a Markov chain by Aldous on binary trees, and show that an unrooted version of the chain has relaxation time of exactly order n2 , whilst the relaxation time for a rooted version is at least of order n2 and at most of order n3−α . Secondly, for general choice of γ, we generalise and further develop previous work by Forman et al. (2018, 2020) in the binary special cases to construct a Markov chain on multifurcating trees with stationary distribution induced by the (α, γ)-growth process. The technique we deploy utilizes the construction of a growth process and a down-up Markov chain on trees with planar structure. Our construction ensures that natural projections of the down-up chain are Markov chains in their own right. We establish label dynamics that at the same time preserve the labelled (α, γ) distribution and keep the branch points between the k smallest labels for order n2 time steps for all k ≥ 2. We conjecture the existence of diffusive scaling limits generalising the “Aldous diffusion” by Forman et al. (2018+) as a continuum-tree-valued process and the “algebraic α-Ford tree evolution” by Löhr et al. (2018+) and by Nussbaumer and Winter (2020) as a process in a space of algebraic trees.

We study composition-valued Markov chains that appear naturally in the frame-work of up-down Chinese Restaurant Processes (CRPs), introducing first discrete time models as in a similar way to those introduced by Petrov (2009), and also in continuous time via a Poissonisation technique similar to that used in Pal (2011). As time evolves in the continuous time model, new customers arrive (up-step) and existing customers leave (down-step) at suitable rates derived from the ordered CRP of Pitman and Winkel (2009). We relate such up-down CRPs to the splitting trees of Lambert (2010) inducing spectrally positive Lévy processes. Conversely, we develop a theorem of Ray–Knight type to recover more general up-down CRPs from the heights of Lévy processes with jumps marked by integer-valued paths. We further establish limit theorems for the Lévy process and the integer-valued paths that connects to work by Forman et al. (2018+) on interval partition diffusions. Fulman 2009 shows that the framework of commutation relations can be used to study the behaviour of discrete time down-up Markov chains, and he applies this to the unordered up-down (α,θ)-CRP from Pitman 2006. We demonstrate that these techniques still yield valid results when applied to the ordered down-up (α,θ)-CRP of Pitman and Winkel 2009, and generalise a theorem of Fulman 2009 on the explicitform and asymptotics of the maximal separation distance from the case θ= 1 to general the case θ > 0.

BACKGROUND Tricuspid regurgitation is associated with increased rates of heart failure (HF) and mortality. Transcatheter tricuspid valve interventions (TTVI) are promising, but the clinical benefit is unknown. OBJECTIVES The purpose of this study was to investigate the potential benefit of TTVI over medical therapy in a propensity score matched population. METHODS The TriValve (Transcatheter Tricuspid Valve Therapies) registry collected 472 patients from 22 European and North American centers who underwent TTVI from 2016 to 2018. A control cohort formed by 2 large retrospective registries enrolling medically managed patients with >= moderate tricuspid regurgitation in Europe and North America (n = 1,179) were propensity score 1:1 matched (distance +/- 0.2 SD) using age, EuroSCORE II, and systolic pulmonary artery pressure. Survival was tested with Cox regression analysis. Primary endpoint was 1-year mortality or HF rehospitalization or the composite. RESULTS After matching, 268 adequately matched pairs of patients were identified. Compared with control subjects, TTVI patients had lower 1-year mortality (23 +/- 3% vs. 36 +/- 3%; p = 0.001), rehospitalization (26 +/- 3% vs. 47 +/- 3%; p < 0.0001), and composite endpoint (32 +/- 4% vs. 49 +/- 3%; p = 0.0003). TTVI was associated with greater survival and freedom from HF rehospitalization (hazard ratio [HR]: 0.60; 95% confidence interval [CI]: 0.46 to 0.79; p = 0.003 unadjusted), which remained significant after adjusting for sex, New York Heart Association functional class, right ventricular dysfunction, and atrial fibrillation (HR: 0.39; 95% CI: 0.26 to 0.59; p < 0.0001) and after further adjustment for mitral regurgitation and pacemaker/defibrillator (HR: 0.35; 95% CI: 0.23 to 0.54; p < 0.0001). CONCLUSIONS In this propensity-matched case-control study, TTVI is associated with greater survival and reduced HF rehospitalization compared with medical therapy alone. Randomized trials should be performed to confirm these results. (C) 2019 by the American College of Cardiology Foundation.

Surimono reflect cultural and social facets of urban life in late Edo period Japan. Thus far, most surimono research was focused on the art historic qualities of the material, regularly also taking the interplay between poetry and image into account. The research presented here places surimono in a greater perspective by including the literary antecedents of the content, the cultural background of the kyōka world and the social networks of poets.Fundamental to the aim of this research is to expose how kyōka provided spheres where people with a cultural interest could join in a literary pursuit that allowed them to fully incorporate their appreciation for and knowledge of the classics. I argue that surimono and kyōka books are deeply rooted in a literary tradition and aimed at an audience of amateur poets who enjoyed honing their wit and culture, creating a world of their own with self-imposed regulations. Despite the initial mocking stance towards the classics seen in early stages of the renewed kyōka popularity in Edo, I contend that surimono, well as other kyōka related materials, show a specific rediscovery and reception of a literary past, which coincides with a period of cultural self-identification in Edo society.