Pith. sign in

REVIEW 3 major objections 5 minor 45 references

Universality of clone dynamics during tissue development

T0 review · 3 major / 5 minor · reviewed 2026-08-14 · deepseek-v4-flash

Pith's one-line read During development, labelled cell clusters converge to a universal log-normal size distribution set by merger and fragmentation, not by cell fate.

desk verdict Genuine scaling collapse and a plausible RG mechanism, but the universal log-normal shape is fitted, not derived, so the quantitative claim is softer than the paper suggests. read the letter →

arxiv 1909.01439 v1 pith:SPLRQFND submitted 2019-08-30 q-bio.TO physics.bio-ph

classification q-bio.TOphysics.bio-ph
keywords clonaldynamicslineagetracingscalingbehaviouruniversalitycoagulation-fragmentationlog-normaldistributiontissuedevelopmentrenormalizationgroup
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

During embryonic development, the sizes of genetically labelled cell clusters become statistically simple: once each cluster size is divided by the average cluster size, the distributions measured at different times, in different heart regions, and even in different organs collapse onto one curve. The paper argues this collapse is not a peculiarity of heart development but a universal consequence of two physical processes, cluster merger and cluster fragmentation, which come to dominate fluctuations as the tissue grows. To show this, the authors map clone dynamics onto the classical theory of aerosol droplets, where droplets coagulate and break up, and then apply a renormalization argument to the mean-field kinetic equations. The claimed result is that the scaling function $\phi$ in $f(x,t)=\phi(x/\langle x(t)\rangle)$ is universal and well approximated by a log-normal distribution, while cell fate decisions only set the average cluster size. A sympathetic reader would care because the result changes what can be learned from lineage tracing: in developing tissues, the shape of the clone-size distribution has little to say about cell fate, and fate information must be sought in the mean size or in early-time, small-cluster deviations.

What carries the argument

The central object is the cluster size distribution $f(x,t)$, the number of labelled clusters of size $x$ at time $t$, together with its kinetic Master equation combining a growth operator, a fragmentation operator, and a merging operator. The argument is carried by a dynamic renormalisation scheme: whenever a cell divides, cluster sizes are rescaled by the increase in tissue size, $x\to x/(1+\delta X)$, and time is rescaled so that merging and fragmentation rates remain constant. Under this scheme the growth-induced diffusion term scales as $X_0(t)^{\beta-2}$, while the merging and fragmentation terms scale as $X_0(t)^{\gamma+1}\mu$ and $X_0(t)^{\alpha+1}\phi$; for homogeneous kernels with $\alpha,\gamma\ge 0$, the latter dominate, so the asymptotic distribution is controlled by a merger-fragmentation fixed point. For the specific kernels derived from diffusive cluster motion and linear fragmentation with a small-size cutoff, the fixed-point distribution is well approximated by a log-normal, matching the empirical scaling function.

What would settle it

Measure the rescaled cluster-size distribution in a developing tissue at several time points once the mean cluster size is many cell diameters, using a labelling scheme with negligible clone merger (very low density). If the small-size tail does not converge to the predicted scaling form, or if distributions from different time points do not collapse when rescaled by the mean, the claim fails. Equivalently, in a tissue where fragmentation is suppressed by cohesive growth, the theory predicts a systematic deviation from the universal curve; observing the same universal collapse there would contradict the mechanism.

Watch

Extended reading notes

Core claim

The paper's central discovery is that clonal dynamics during tissue development converge to a critical state in which labelled-cluster size statistics are universal. Concretely, for a developing tissue with active merger and fragmentation of labelled clones, the distribution of cluster sizes takes the scaling form $f(x,t)=\phi(x/\langle x(t)\rangle)$, where the scaling function is set solely by the merger and fragmentation kernels and is approximately log-normal. This is established by coarse-graining a mean-field kinetic equation that includes growth, merging, and fragmentation; under successive rescaling of cluster sizes and time, the growth-driven diffusion term becomes subleading while the renormalised merger and fragmentation terms, with rates $X_0(t)^{\alpha+1}\phi$ and $X_0(t)^{\gamma+1}\mu$, control the fixed point. The authors test the prediction against clonal data from mouse heart, liver, pancreas, and zebrafish heart, finding collapse onto the universal log-normal curve, with a documented exception for cohesive pancreatic acinar clusters, which deviate because fragmentation is suppressed. The paper therefore claims that the collective physical kinetics, not the molecular details of cell fate, governs the shape of clone size distributions in development.

Load-bearing premise

The load-bearing premise is that in an expanding tissue the merger and fragmentation of labelled clusters grow fast enough with organ size to outweigh the randomizing effect of cell division, so that the asymptotic shape of the cluster size distribution is set by merger and fragmentation alone; if those rates do not keep pace, or fragmentation creates arbitrarily small pieces, the universal scaling regime is not reached.

Editorial extensions

If this is right

  • In clonal tracing experiments in developing organs, the shape of the labelled-cluster size distribution cannot by itself reveal cell fate; the mean cluster size, and the timing of approach to scaling, are the information-carrying observables.
  • Lineage-specific information can still be recovered from short times after labelling and from small cluster sizes, because convergence to the universal scaling form is slowest there.
  • Deviations from the universal log-normal distribution become diagnostic: a tissue whose clones cannot fragment, such as cohesive pancreatic acinar precursors, will fall off the universal curve.
  • If merging is negligible, distinct division modes (asymmetric versus symmetric) produce distinct small-size signatures, so clonal data can still discriminate fate behaviour in that regime.
  • The same universal fixed point should govern clone statistics in regeneration and tumour growth, where tissue expansion, merger, and fragmentation are also active.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • One consequence the authors leave implicit is a caution for high-density lineage tracing: without testing for convergence to the universal curve, an apparent difference in clone-size distributions between genetic conditions may simply reflect a difference in average clone size rather than a difference in fate behaviour.
  • The log-normal shape is tied to the coarse-graining cutoff in the fragmentation kernel, so changing imaging resolution or detection threshold could shift the left tail of the measured distribution; separating that artefact from biology would be essential in any quantitative analysis.
  • The renormalisation picture predicts that any expanding tissue with sufficiently fast merger and fragmentation should show the same collapse, even if proliferation is spatially heterogeneous; testing this in organoids or engineered tissues with tunable growth and adhesion would directly probe the claimed fixed point.
  • If the universal form is reliable, fitting the empirical distribution to the log-normal curve provides a cheap way to estimate the average cluster size from partial data, which may be useful when only a subset of clone sizes can be resolved.
Share X Bluesky LinkedIn Reddit HN

Signed reviews

No signed human review yet.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

3 major / 5 minor

Summary. The manuscript argues that the size distribution of labelled cell clusters in developing tissues converges asymptotically to a universal scaling form that is controlled entirely by merger and fragmentation events, independent of cell-fate behaviour. Empirically, the authors analyse clonal tracing data from mouse heart (Mesp1-Confetti), mouse liver, mouse pancreas, and zebrafish heart, and show that cluster sizes rescaled by their mean collapse onto a common log-normal curve (Fig. 3, Fig. S2). The theoretical framework maps clone dynamics onto a mean-field coagulation-fragmentation equation with growth, applies a dynamic renormalization scheme in which cluster sizes are rescaled by tissue growth, and concludes that growth-related fluctuations scale as X0^{β−2} while merger and fragmentation scale as X0^{γ+1} and X0^{α+1}, so that an asymptotic merger-fragmentation fixed point controls the scaling distribution (Supplemental Theory §1.1). Specific merging and fragmentation kernels are derived for diffusing clusters, the scaled equation is solved by Monte Carlo simulation, and the resulting stationary distribution is reported to be log-normal (Supplemental Theory §2.3). The paper also describes how lineage-specific information can be recovered from short-time and small-size deviations from universality and tabulates predicted distributions for different growth modes.

Significance. If the central claims hold, the paper identifies a new universality class for clonal dynamics in development and provides a practical tool for lineage tracing: in the scaling regime, the average cluster size is the only relevant scale, and deviations from the universal form can be used to infer cell-fate behaviour. The empirical scaling collapse across four tissues and two organisms is a substantial result, and the renormalization-group mapping to aerosol coagulation-fragmentation theory is an elegant conceptual contribution. The paper is also commendably transparent: it reports the exact exponential solution for a constant merger kernel, notes that the Monte Carlo merging rate is computed with a log-normal ansatz that is 'justified post hoc', and describes its own expressions in Table 1 as empirical approximations. The main limitation is that the specific log-normal functional form is not derived from the stated kernels; the theoretical derivation supports scaling and universality of the fixed point but not the particular shape, so the quantitative claim of a universal log-normal distribution is weaker than the text suggests.

major comments (3)
  1. [Supplemental Theory §2.3, Eqs. (30), (45), (52)] The log-normal scaling function is not derived from the merger and fragmentation kernels. For the same homogeneity exponents (α=γ=0) the only analytic solution of the renormalized equation, obtained for a constant merging kernel, is the exponential in Eq. (52), not a log-normal. The log-normal in Eq. (45) comes from Monte Carlo simulations of Eq. (21), but those simulations compute the total merging rate using the log-normal ansatz of Eq. (30), which the text states will be 'justified post hoc' before confirming log-normality; the moment closure in Eqs. (31)-(33) inherits the same assumption. The lattice simulations show scaling collapse but do not independently test the functional form. The theory therefore establishes the existence of a universal scaling form whose shape depends on the kernel details, but not the specific log-normal shape; the log-normal curve used in Fig. 3 is an empirical fit, not a prediction. This is load-bearing for the statement that the distribution is 'determined entirely by merger and fragmentation': as written, it should be 'determined up to an undetermined, kernel-dependent shape'. Please derive the shape from the kernels, provide a simulation that does not assume log-normality in the rates, or explicitly reframe the log-normal as an empirical approximation.
  2. [Supplemental Theory §1.1, Eqs. (16)-(17)] The renormalization argument requires that the rescaled merger and fragmentation rates X0^{γ+1} μ and X0^{α+1} φ eventually dominate the growth-induced diffusion term X0^{β−2}, which presupposes α,γ≥0 and a tissue in which both rates grow with organ size. The value α=0 is inferred from the fragment-number data in §2.2, but γ=0 follows from the diffusion-limited kernel of Eqs. (35)-(41), where the diffusion constant of a cluster scales as the inverse mass in three dimensions. In a real tissue, if merger and fragmentation rates do not increase with organ size (or if spatial correlations invalidate the mean-field approximation), the asymptotic merger-fragmentation fixed point may not be reached within the developmental window. This is the weakest premise of the derivation; a concrete way to test it would be to estimate merger/fragmentation rates at different developmental stages and check whether the scaling collapse persists when the growth exponent β is varied.
  3. [Fig. 3 and Fig. S2] The empirical case for the log-normal shape rests on maximum-likelihood fits and quantile-quantile plots against the log-normal distribution, with no comparison to alternative two-parameter distributions (e.g., gamma, Weibull, or the exponential of Eq. (52)). Since the theoretical derivation does not independently predict log-normality (major comment 1), the collapse in Fig. 3 supports scaling but not the superiority of the log-normal over other forms; the Fig. 3 caption calls the fitted curve the 'predicted universal log-normal dependence', which conflates fitting with prediction. A likelihood-ratio or information-criterion comparison between candidate scaling forms would materially strengthen the universality claim.
minor comments (5)
  1. [Supplemental Theory Eq. (4)] In the first merger term of Eq. (4), the upper integration limit is written as r, which is not defined; it should presumably be x (or ρ in rescaled variables).
  2. [References] The reference list contains two entries numbered 24 (Schindelin et al., Nat. Methods, and Olesen et al., Phys. Rev. E); these need separate numbers or the in-text citations must be updated.
  3. [Abstract] The phrase 'the time evolution their progeny' is missing 'of'; please correct.
  4. [Fig. 1 caption] The caption states that rescaled distributions 'perfectly overlapped ped'; this should read 'overlapped'.
  5. [Table 1] The entries in the merging-and-fragmentation column are described in the table footnote as 'empirical approximations', but the main text uses them as if they were derived; please mark this distinction in the main text as well.

Circularity Check

2 steps flagged · score 6.0 of 10

The log-normal universal shape is not predicted from the theory: the Monte Carlo confirmation assumes a log-normal ansatz, the exact analytic control solution is exponential, and the experimental 'universal curve' is fitted, not predicted.

  1. self definitional [Supplemental Theory §1.3.1, Eqs. (30)-(33); confirmation in §2.3, Eq. (45)]
    "We assume a log-normal cluster size distribution, which is common practice in the literature, and will be justified post hoc, f(x,t)=N(t)/(2πσx) exp[-(ln x-μ)^2/(2σ^2)] ... The right hand side is an approximation to the overall merging rate, which we used to calculate the probability of merging events in each Monte Carlo cycle."

    The kinetic Monte Carlo solver computes the total merger rate from an assumed log-normal form (Eqs. 30-33), so the simulated dynamics is steered by the very shape it is later said to confirm. The paper's later statement that the stationary state 'is well described by a log-normal cluster size distribution' is therefore a post hoc confirmation of an input, not an independent derivation. The text itself labels the ansatz as 'justified post hoc', making the circularity explicit.

  2. fitted input called prediction [Main text Fig. 3 caption; Supplemental Theory §2.3, value of σ]
    "Experimental cumulative cluster size distributions for (C) mouse liver ... collapse onto the predicted universal log-normal dependence fitted by maximum likelihood estimation (grey). ... Values for the standard deviation of logarithmic cluster sizes obtain values between 0.5 and 1.5 depending on the precise values of the cutoff ... and compared to a fitted value of 1.05 obtained for the universal curve plotted in Fig. 3F of the main text."

    The shape parameter σ of the 'predicted universal log-normal dependence' is fitted to the data by maximum likelihood (σ≈1.05), while the theory supplies only a range (0.5-1.5) that depends on unknown cutoff and kernel details. Thus the empirical collapse is presented as confirmation of a functional form whose parameter is itself fit from the data. The scaling collapse itself is real and independent, but the specific log-normal shape is not predicted; it is an input to the fit, so calling it 'predicted' converts a fit into a confirmation.

full rationale

The non-circular core of the paper is the renormalization-group argument in Supplemental Theory Eqs. (16)-(17) and (21): if merger and fragmentation kernels are homogeneous with α,γ≥0 and the flow reaches the merger-fragmentation fixed point, cluster-size distributions collapse onto a scaling form. The data collapse in Fig. 1H and the lattice simulations support this scaling claim, and that part does not reduce to a fit. The circularity is confined to the specific log-normal claim. In Supplemental Theory §1.3.1, the Monte Carlo merger rate is computed from a log-normal ansatz ('will be justified post hoc'), so the subsequent finding that the simulations produce a log-normal distribution is not independent. Moreover, the only exact analytical solution quoted for the same homogeneity exponents (α=γ=0, constant-kernel simplification) is exponential, not log-normal: 'The size distribution of labelled clusters therefore follows an exponential form' (Eq. 52). This shows that the log-normal shape is not a consequence of the kinetic equations alone. Empirically, the main-text Fig. 3 caption calls the fitted curve 'the predicted universal log-normal dependence', while the supplemental text gives a fitted σ=1.05 within a theoretical range 0.5-1.5, so the shape parameter is fit, not predicted. The self-citations present (e.g., Refs. 5 and 9) refer to empirical data and prior modelling rather than to an unverified uniqueness theorem, so they do not by themselves add circularity. Overall, the scaling/universality-of-the-fixed-point claim has independent content, but the quantitative log-normal universality claim is partially circular: an ansatz-assisted numerical confirmation plus a post hoc fit. Hence score 6.

Assumptions & free parameters 3 free parameters · 6 assumptions · 0 invented entities

The central scaling prediction rests on standard coagulation-fragmentation mathematics, several domain assumptions about how cell clusters grow, move, merge, and fragment, and two ad hoc modeling choices unique to this paper: the renormalization scheme that discards growth fluctuations, and the log-normal ansatz used to estimate Monte Carlo merging rates. No new physical entities are introduced.

free parameters (3)
  • Log-normal width sigma = 1.05 for the universal curve in Fig. 3F
    The scaling curve is fitted to the combined experimental data by maximum likelihood estimation; the theory does not predict sigma analytically.
  • Fractal dimension d_f = 2
    Chosen by hand in the merging kernel (Supplemental Theory Eq. 42); the authors state the scaling shape is not sensitively dependent on this choice.
  • Fragmentation cutoff z_c = Not specified numerically; model parameter
    A lower-size cutoff in the fragmentation kernel is introduced to prevent infinitesimal fragments and to recover log-normality; its value is not derived or measured, only its existence is shown to matter.
assumptions (6)
  • standard math Mean-field approximation is valid because the critical dimension of coagulation-fragmentation processes is below one.
    Invoked in Supplemental Theory after Eq. (4), citing Family et al.; it justifies neglecting spatial correlations in the kinetic equations.
  • domain assumption Cell division produces multiplicative growth of cluster size, L_growth[f] = -d/dx[x^beta f] with beta=1 for symmetric self-renewal and beta=0 for asymmetric division.
    Supplemental Theory Eq. (2); this defines the growth operator and is used in the renormalization analysis.
  • domain assumption Clusters undergo diffusive motion due to random tissue forces, yielding a Smoluchowski merging kernel K(x,x') proportional to (x^{1/d_f}+x'^{1/d_f})(x^{-1/d_f}+x'^{-1/d_f}) with fractal dimension d_f set to 2.
    Supplemental Theory, 'Derivation of the merging kernel', Eqs. (40)-(42); the three-dimensional spherical result is extended to d_f=2 by hand, with the claim that results do not depend sensitively on d_f.
  • domain assumption Fragmentation rate is linear in cluster size with a uniform daughter-size distribution and a lower-size cutoff z_c; alpha=0.
    Supplemental Theory, 'Derivation of the fragmentation kernel', Eq. (44); inferred from clonal fragment statistics in heart development, and needed to avoid unphysical power-law tails.
  • ad hoc to paper The renormalization scheme removes the time derivative of the first moment and treats growth fluctuations as scaling as X0^{beta-2} while merger/fragmentation scale as X0^{alpha+1} and X0^{gamma+1}.
    Supplemental Theory, 'Renormalisation of the kinetic equations', Eqs. (11)-(17); this coarse-graining is a modeling choice specific to the paper and is the load-bearing step that makes cell-fate processes asymptotically irrelevant.
  • ad hoc to paper The Monte Carlo merging rate is computed by assuming a log-normal cluster size distribution before convergence is established.
    Supplemental Theory, 'Monte Carlo simulations', Eq. (30); the authors state this assumption 'will be justified post hoc', which is a circular element in the numerical confirmation of log-normality.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Universality of clone dynamics during tissue development." pith.science (2026). https://pith.science/paper/SPLRQFND

@misc{pith2026190901439,
  author       = {Pith},
  title        = {Pith review of: Universality of clone dynamics during tissue development},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/SPLRQFND}},
  note         = {Machine review of arXiv:1909.01439}
}
read the original abstract

The emergence of complex organs is driven by the coordinated proliferation, migration and differentiation of precursor cells. The fate behaviour of these cells is reflected in the time evolution their progeny, termed clones, which serve as a key experimental observable. In adult tissues, where cell dynamics is constrained by the condition of homeostasis, clonal tracing studies based on transgenic animal models have advanced our understanding of cell fate behaviour and its dysregulation in disease. But what can be learned from clonal dynamics in development, where the spatial cohesiveness of clones is impaired by tissue deformations during tissue growth? Drawing on the results of clonal tracing studies, we show that, despite the complexity of organ development, clonal dynamics may converge to a critical state characterized by universal scaling behaviour of clone sizes. By mapping clonal dynamics onto a generalization of the classical theory of aerosols, we elucidate the origin and range of scaling behaviours and show how the identification of universal scaling dependences may allow lineage-specific information to be distilled from experiments. Our study shows the emergence of core concepts of statistical physics in an unexpected context, identifying cellular systems as a laboratory to study non-equilibrium statistical physics.

Figures

Figures reproduced from arXiv: 1909.01439 by the authors.

Figure 1
Figure 1. Illustration of the dynamic coarse graining procedure. The rescaling compensates the overall growth of the tissue (left). While in the presence of merging and fragmentation typical cluster sizes increase in size over time, the characteristic renormalised size is time independent (right, illustration of a typical stochastic realisation). namics asymptotically converges to a “critical” process, which is dominated by t… view at source ↗
Figure 2
Figure 2. Statistics of the sizes of monoclonal fragments (a) Average clone size as a function of the number of fragments. Error bars signify 95% confidence intervals. (b) Histogram of the relative sizes of fragments (proportion of the total clone size) in clones consisting of two fragments. (b) Histogram of the relative sizes of fragments in clones consisting of three fragments. from the clonal assay. We can estimate ˜b(z) b… view at source ↗
Figure 3
Figure 3. (a) Asymptotic solution of the merging-fragmentation equation (21) for different values of the (fractal) dimension of labelled clusters, df . The shape of the scaling form is independent of df . (b) Asymptotic solution the merging-fragmentation-fragmentation equation with df = 2, and different values of the fragmentation cutoff. The probability distributions agrees excellently with a log-normal form. For small value… view at source ↗
Figures from the paper (1 more)
Figure 4
Figure 4. Figure 4: Asymptotic numerical solutions of the time evolution equations (4). Solutions show scaling behaviour and universality. Fits for small and large cluster sizes are coloured red and blue, respectively. Parameters were chosen such that hxi 1: Homeostasis: ϕ = 5 · 10−4 , µ …

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

45 extracted references · 45 canonical work pages

  1. [1]

    Kretzschmar, F

    K. Kretzschmar, F. M. Watt, Lineage tracing. Cell. 148, 33–45 (2012)

  2. [2]

    Blanpain, B

    C. Blanpain, B. D. Simons, Unravelling stem cell dynamics by lineage tracing. Nat. Rev. Mol. Cell Biol. 14, 489–502 (2013)

  3. [3]

    S. J. Morrison, A. C. Spradling, Stem Cells and Niches : Mechanisms That Promote Stem Cell Maintenance throughout Life. Cell. 132, 598–611 (2008)

  4. [4]

    A. M. Klein, B. D. Simons, Universal patterns of stem cell fate in cycling adult tissues. Development. 138, 3103–11 (2011)

  5. [5]

    Rulands, B

    S. Rulands, B. D. Simons, Tracin g cellular dynamics in tissue development, maintenance and disease. Curr. Opin. Cell Biol. 43, 38–45 (2016)

  6. [6]

    A. M. Klein, D. P. Doupé, P. H. Jones, B. D. Simons, Mechanism of murine epidermal maintenance: Cell division and the voter model. Phys. Rev. E. 77, 31907 (2008)

  7. [7]

    Bondue, C

    A. Bondue, C. Blanpain, Mesp1: A Key Regulator of Cardiovascular Lineage Commitment. Circ. Res. 107, 1414–1427 (2010)

  8. [8]

    Lescroart et al., Early lineage restriction in temporally distinct populations of Mesp1 progenitors during mammalian heart development

    F. Lescroart et al., Early lineage restriction in temporally distinct populations of Mesp1 progenitors during mammalian heart development. Nat. Cell Biol. 16, 829–840 (2014)

Show all 45 references
  1. [9]

    Chabab et al., Uncovering the Number and Clonal Dynamics of Mesp1 Progenitors during Heart Morphogenesis

    S. Chabab et al., Uncovering the Number and Clonal Dynamics of Mesp1 Progenitors during Heart Morphogenesis. Cell Rep. 14, 1–10 (2016)

  2. [10]

    Wuidart et al., Quantitative lineage tracing strategies to resolve multipotency in tissue -specific stem cells

    A. Wuidart et al., Quantitative lineage tracing strategies to resolve multipotency in tissue -specific stem cells. Genes Dev. 30, 1261–1277 (2016)

  3. [11]

    S. M. Meilhac et al., A retrospective clonal analysis of the myocardium reveals two phases of clonal growth in the developing mouse heart. Development. 130, 3877–89 (2003)

  4. [12]

    Sedmera, R

    D. Sedmera, R. P. Thompson, Myocyte proliferation in the developing heart. Dev. Dyn. 240, 1322– 34 (2011)

  5. [13]

    Foret et al., A General Theoretical Framework to Infer Endosomal Network Dynamics from Quantitative Image Analysis

    L. Foret et al., A General Theoretical Framework to Infer Endosomal Network Dynamics from Quantitative Image Analysis. Curr. Biol. 22, 1381–1390 (2012). 14

  6. [14]

    P. L. Krapisky, S. Redner, E. Ben -Naim, A Kinetic View of Statistical Physics (Cambridge University Press, Cambridge, 2010)

  7. [15]

    S. K. Friedlander, Smoke, Dust, and Haze (Oxford University Press, Oxford, 2000)

  8. [16]

    E. M. Hendriks, M. H. Ernst, R. M. Ziff, Coagulation equations with gelation. J. Stat. Phys. 31, 519– 563 (1983)

  9. [17]

    Ranft et al., Fluidization of tissues by cell division and apoptosis

    J. Ranft et al., Fluidization of tissues by cell division and apoptosis. Proc. Natl. Acad. Sci. U. S. A. 107, 20863–8 (2010)

  10. [18]

    Redner, in Disorder and Fracture, J

    S. Redner, in Disorder and Fracture, J. C. Charmet, S. Roux, E. Guyon, Eds. (Springer US, Boston, MA, 1990), vol. 204 of NATO ASI Series

  11. [19]

    S. K. Friedlander, C. S. Wang, The self -preserving particle size distribution for coagulation by brownian motion. J. Colloid Interface Sci. 22, 126–132 (1966)

  12. [20]

    Gupta, K

    V. Gupta, K. D. Poss, Clonally dominant cardiomyocytes direct heart morphogenesis. Nature. 484, 479–84 (2012)

  13. [21]

    Clayton et al., A single type of progenitor cell maintains normal epidermis

    E. Clayton et al., A single type of progenitor cell maintains normal epidermis. Nature. 446, 185–9 (2007)

  14. [22]

    Saga et al., MesP1 is expressed in the heart precursor cells and required for the formation of a single heart tube

    Y. Saga et al., MesP1 is expressed in the heart precursor cells and required for the formation of a single heart tube. Development. 126, 3437–47 (1999)

  15. [23]

    H. J. Snippert et al., Intestinal crypt homeostasis results from neutral competition between symmetrically dividing Lgr5 stem cells. Cell. 143, 134–44 (2010)

  16. [24]

    Schindelin et al., Fiji: an open -source platform for biological -image analysis

    J. Schindelin et al., Fiji: an open -source platform for biological -image analysis. Nat. Methods. 9, 676–682 (2012)

  17. [25]

    two-time

    P. Olesen et al., Diffusion, fragmentation, and coagulation processes: Analytical and numerical results. Phys. Rev. E 72, 031103 (2006) 15 Acknowledgements: B.D.S. acknowledges the support of the Wellcome Trust (grant number 098357/Z/12/Z). F.L. is supported by a long-term EMB...

  18. [26]

    This process occurs at a rate that scales in proportion to the number of cells outside the cluster, [X(1− ρ)]β

    A cell which is not part of a given cluster divides such that the relative fraction of the labeled cluster decreases multiplicatively, ρ→ x/(X + 1) = ρ / (1 + 1/X). This process occurs at a rate that scales in proportion to the number of cells outside the cluster, [X(1− ρ)]β

  19. [27]

    A cell within a given cluster divides, yielding a multiplicative contribution from the expansion of the tissue and an additive contribution from the growth of the cluster, ρ→ (x + 1)/(X + 1) = ρ / (1 + 1/X) + 1 / (1 + X). In expand- /one.taboldstyle /e.sc/m.sc/e.sc/r.sc/g.sc/e...

  20. [28]

    α > γ: fragmentation processes dominate fluctuations

  21. [29]

    α = γ: merging and fragmentation processes contribute equally to fluctua- tions

  22. [30]

    critical

    α < γ: Merging processes dominate fluctuations. In each of these regimes large-scale fluctuations are dominated by different pro- cesses. To continue our analysis, we now study each of these regimes in more detail. /one.taboldstyle./two.taboldstyleExistence of scaling solutions ...

  23. [31]

    This limit is of the order⟨ρX0(t)⟩

    The coarse-graining procedure imposes a lower limit on the possible sizes of daughter fragments. This limit is of the order⟨ρX0(t)⟩. If typical cluster sizes are large, the resolution of the microscope limits the quantification of small fragments. Even above the detection thres...

  24. [32]

    Realistic fragmentation kernels therefore cannot produce infinitesimally small frag- ments

    If typical cluster sizes are small, the sizes of daughter fragments cannot be smaller than single cells. Realistic fragmentation kernels therefore cannot produce infinitesimally small frag- ments. We take into account this fact by introducing a cut-off to the uniform frag- ment...

  25. [33]

    Convergence to scaling behaviour occurs exponentially on a time scale deter- mined by µ and ϕ. Cell fate specific information can therefore be retained from the short term dynamics, where time is much shorter than the time scales associated with the merging and fragmentation ra...

  26. [34]

    Small-size dependencies, 1 ≪ x≪⟨ x⟩, converge to the universal form last. Importantly, to compare experimental data with the modelling predictions in addition to cell fate related processes, merging and fragmentation needs to be specifically taken into account

  27. [35]

    Given a large enough sample size, the shape of the scaling function might show specific dependences in different kinds of tissues

    Last, while explicit information on cell fate is erased, merging and fragmen- tation are emergent processes resulting from many cell fate decisions. Given a large enough sample size, the shape of the scaling function might show specific dependences in different kinds of tissues...

  28. [36]

    Friedlander

    Sheldon K. Friedlander. Smoke, Dust, and Haze. Oxford University Press, Ox- ford, 2000

  29. [37]

    Cambridge University Press, Cambridge, 2010

    Pavel L Krapisky, Sidney Redner, and Eli Ben-Naim.A Kinetic View of Statistical Physics. Cambridge University Press, Cambridge, 2010

  30. [38]

    Fereydoon Family, Paul Meakin, and John M. Deutch. Kinetics of coagulation with fragmentation: Scaling behavior and fluctuations. Physical Review Letters, 57:727–730, 1986

  31. [39]

    On the stability of coagula- tion—fragmentation population balances

    Dennis R Vigil and Robert M Ziff. On the stability of coagula- tion—fragmentation population balances. Journal of Colloid and Interface Sci- ence, 133(1):257–264, 1989

  32. [40]

    Statistical Theory of Fragmentation

    Sidney Redner. Statistical Theory of Fragmentation. In J. C. Charmet, S. Roux, and E. Guyon, editors, Disorder and Fracture, volume 204 of NATO ASI Series. Springer US, Boston, MA, 1990

  33. [41]

    K. W. Lee and H. Chen. Coagulation rate of polydisperse particles. Aerosol science and technology, 3(3):327–334, 1984

  34. [42]

    Fluidization of tissues by cell division and apoptosis

    Jonas Ranft, Markus Basan, Jens Elgeti, Jean-François Joanny, Jacques Prost, and Frank Jülicher. Fluidization of tissues by cell division and apoptosis. Proceedings of the National Academy of Sciences of the United States of America, 107(49):20863–8, dec 2010. References 39

  35. [43]

    Simu- lation of aerosol agglomeration in the free molecular and continuum flow regimes

    Raymond D Mountain, George W Mulholland, and Howard Baum. Simu- lation of aerosol agglomeration in the free molecular and continuum flow regimes. Journal of Colloid and Interface Science, 114(1):67–81, nov 1986

  36. [44]

    Early lineage restriction in temporally distinct populations of Mesp1 progenitors during mammalian heart development

    Fabienne Lescroart, Samira Chabab, Xionghui Lin, Steffen Rulands, Catherine Paulissen, Annie Rodolosse, Herbert Auer, Younes Achouri, Christine Dubois, Antoine Bondue, Benjamin D Simons, and Cédric Blanpain. Early lineage restriction in temporally distinct populations of Mesp1...

  37. [45]

    Coagulation with fragmentation

    J D Barrow. Coagulation with fragmentation. Journal of Physics A: Mathematical and General, 14(3):729–733, mar 1981. /a.sc /r.sc/e.sc/s.sc/c.sc/a.sc/l.sc/i.sc/n.sc/g.sc /o.sc/f.sc /o.sc/t.sc/h.sc/e.sc/r.sc /c.sc/e.sc/l.sc/l.sc /f.sc/a.sc/t.sc/e.sc /p.sc/r.sc/o.sc/c.sc/e.sc/s.s...

Pith tools

Reviewed August 14, 2026 · model on record in the stance chip above.