State Of Dynamic Equilibrium Research Articles

Determination of secretory granule maturation times in pancreatic islet β-cells by serial block-face electron microscopy

It is shown how serial block-face electron microscopy (SBEM) of insulin-secreting β-cells in wild-type mouse pancreatic islets of Langerhans can be used to determine maturation times of secretory granules. Although SBEM captures the β-cell structure at a snapshot in time, the observed ultrastructure can be considered representative of a dynamic equilibrium state of the cells since the pancreatic islets are maintained in culture in approximate homeostasis. It was found that 7.2 ± 1.2% (±st. dev.) of the β-cell volume is composed of secretory granule dense-cores exhibiting angular shapes surrounded by wide (typically ≳100 nm) electron-lucent halos. These organelles are identified as mature granules that store insulin for regulated release through the plasma membrane, with a release time of 96 ± 12 h, as previously obtained from pulsed 35S-radiolabeling of cysteine and methionine. Analysis of β-cell 3D volumes reveals a subpopulation of secretory organelles without electron-lucent halos, identified as immature secretory granules. Another subpopulation of secretory granules is found with thin (typically ≲30 nm) electron-lucent halos, which are attributed to immature granules that are transforming from proinsulin to insulin by action of prohormone convertases. From the volume ratio of proinsulin in the immature granules to insulin in the mature granules, we estimate that the newly formed immature granules remain in morphologically-defined immature states for an average time of 135 ± 14 min, and the immature transforming granules for an average time of 130 ± 17 min.

The Neoclassical Theory of Term Structure

This study presents a specification for the neoclassical user cost of capital that reflects dynamic processes for debt maturity structure and for pretax cash flows. Equivalencing levered and unlevered user costs reveals tradeoffs between equilibrium financing rates and underlying processes that satisfy a dynamic no-arbitrage equilibrium condition between debt, equity, and costless reversible real investment. The primary finding is that an increase in debt ratio or loan term associates with an increase in equilibrium financing rate – invariance of the neoclassical user cost to leverage implies an endogenous upward sloped yield curve.

Revisited dynamic modeling and eigenvalue analysis of the cable-stayed beam

In this study, the Hamilton’s principle is applied to revisit the dynamic modeling of the cable-stayed beam, and the motion equations governing the nonlinear response of the cable-stayed beam are derived. The corresponding boundary terms are transformed to the dynamic equilibrium conditions through the continuity of the displacement at the anchoring point. Following the standard condensation procedure, the condensed model of the cable-stayed beam is determined. The eigenvalue analysis is performed to determine the closed-form eigenvalue solution of the linear problems, and two types of eigenvalue solution are obtained. It is shown that the frequency spectrum of the cable-stayed beam exhibits the curve veering and crossover phenomena. Corresponding to these phenomena, the mode shapes of the cable-stayed beam may exhibit the coupling characteristic. Finally, the discrete model of the cable-stayed beam is determined, and the possible nonlinear interactions are discussed.

Design, Simulation and Test of Thermal Control System of Centrifuge for Space Utilization

Taking centrifuge system for space utilization as the research object, an active air-cooling thermal control system is put forward. Physical models of the centrifuge thermal control system are built on the basis of simplifying assumptions under actual conditions. A numerical calculation model of centrifuge system is established by using the sliding mesh technique and flow resistance model of heat exchanger is introduced based on the porous medium theory. A numerical analysis of the dynamic heat exchange performance of the centrifuge is carried out and the results show the flow and heat exchange characteristics of each part of the system in the dynamic equilibrium state. Also, the centrifuge system and its heat exchange performance test platform are designed and built, and the monitoring probes are placed at the key position. The curves of the whole equilibrium process of key points are obtained and the test condition is consistent with numerical simulation condition. The equilibrium temperatures of the test are in agreement with that of the numerical analysis, which proves that the numerical model and calculation method are accurate. Meanwhile, the test and numerical analysis results can also improve each other to provide data and supporting techniques for in-orbit engineering utilization of manned space station in future.

Morphodynamic equilibrium of lowland river systems during autoretreat

AbstractLowland river systems (with channel slopes of 10−5 to 10−4) inevitably shift away (retreat upstream) from the receiving basin under a sustained rate of base-level rise, even if the system can maintain a period of advance at the onset of rise. This autogenic pattern of transition from progradation to retrogradation through steady base-level rise and sediment supply is termed “autoretreat.” Using a morphodynamic model of autoretreat, this study explored the varying channel hydrodynamics of lowland fluvial systems and associated stratigraphic record under sustained base-level rise and constant sediment supply. Results from the numerical simulations show that a fluvial system will reach a state of dynamic equilibrium during autoretreat where both the backwater length and the morphodynamic adjustment of the downdip channel profile become steady. Moreover, when this dynamic equilibrium state is realized, simulated systems display a persistent twofold downstream deepening of flow depth across the backwater zone, a pattern that is also present in many natural systems. In general, backwater effects play a key role in the morphodynamics of a lowland fluvial-deltaic system during autoretreat, and this hydrodynamic condition is therefore critical for predicting river responses to sea-level change.

Experimental study on mechanical interaction between buried pipe and soil during freezing

Understanding the frost-induced pipe-soil interaction is very important to address the problem of damage to buried pipelines caused by frost heaving. Herein, a frost heaving experiment was designed to investigate the mechanism of interaction between a buried pipe and frozen soil. Based on the data collected using various sensors, the variations of the soil parameters (such as temperature, water content, soil pressure, and frost heave) and the distributions of the deformation and stress of the pipe were analyzed. Furthermore, the checking calculation of the pipe stress was carried out. The experimental results show that the interaction between the pipe and the soil under frost heaving is a process of coordinated development of various forces and deformations. The pipe is deformed by frost heaving of the soil while the pipe itself restrains the frost heaving. There is a state of dynamic equilibrium between the pipe and the soil. The uneven changes in the internal properties of the soil are related to the restraint of the pipe. For the soil closer to the pipe, when the pipe deformation is small, the pipe restraint on the frost heaving is stronger, the frost heaving force is larger, and the frost heaving is smaller. In addition, the axial stress of a pipe caused by frost heaving can be calculated approximately by the method of bending stress analysis of a beam. The influence of cross-sectional deformation should be considered in the stability calculation of the pipe when the pipe is subjected to large loads. The experimental results can be used as a theoretical reference for pipeline designs in permafrost regions, particularly in the calculation of pipe strength and selection of pipe material.

Defining lung cancer stem cells exosomal payload of miRNAs in clinical perspective.

Since the first publication regarding the existence of stem cells in cancer [cancer stem cells (CSCs)] in 1994, many studies have been published providing in-depth information about their biology and function. This research has paved the way in terms of appreciating the role of CSCs in tumour aggressiveness, progression, recurrence and resistance to cancer therapy. Targeting CSCs for cancer therapy has still not progressed to a sufficient degree, particularly in terms of exploring the mechanism of dynamic interconversion between CSCs and non-CSCs. Besides the CSC scenario, the problem of cancer dissemination has been analyzed in-depth with the identification and isolation of microRNAs (miRs), which are now considered to be compelling molecular markers in the diagnosis and prognosis of tumours in general and specifically in patients with non-small cell lung cancer. Paracrine release of miRs via "exosomes" (small membrane vesicles (30-100 nm), the derivation of which lies in the luminal membranes of multi-vesicular bodies) released by fusion with the cell membrane is gaining popularity. Whether exosomes play a significant role in maintaining a dynamic equilibrium state between CSCs and non-CSCs and their mechanism of activity is as yet unknown. Future studies on CSC-related exosomes will provide new perspectives for precision-targeted treatment strategies.

Modelling the development of dynamic equilibrium on shore platforms

A numerical model was used to determine whether the landward migration of shore platforms at the low tidal level, due to downwearing and possibly other mechanisms, can match the recession caused by wave erosion at the high tidal level. The hybrid model calculated the time required to undercut a cliff face and to remove the debris, and the amount of recession accomplished at the low tidal level during that time. These iterations were repeated over the equivalent of a 40,000 year period. The rates of high tidal erosion calculated during model runs were representative of cliff recession rates recorded in the field, and downwearing rates, specified for each run, were based on data recorded on shore platforms with micro-erosion meters. Almost all runs demonstrated that platform gradients decline asymptotically to a state of dynamic equilibrium that is strongly related to tidal range and rock resistance, although its relationship to wave height varies according to attenuation rates in the surf zone. Periodic changes in rock resistance and continuous changes in cliff height can introduce perturbations that delay equilibrium or, depending on their severity, prevent its occurrence. The conclusion that platforms trend towards dynamic, as opposed to static, equilibrium is contrary to other models which have considered only the effect of wave erosion. The results of this work have important implications for coastal modelling and the estimation of platform lowering for cosmogenic dating.

Fabrication of High-Aspect-Ratio Microwire Electrodes Using a Vertical Liquid Membrane Electrochemical Etching Method

A vertical liquid membrane electrochemical etching method is proposed for the fabrication of high-aspect-ratio microwire electrodes. The potential and current density distributions are simulated using COMSOL software. The simulation results show that the unique potential distribution generated by the proposed method, combined with reciprocating linear motion of the wire electrode, can be used to fabricate microwire electrodes with large aspect ratio. These simulation results are verified experimentally. Different concentrations of electrolyte result in different reaction rates and thus different distributions of the diffusion layer and different bubble flows, resulting in different morphologies of the prepared wire electrodes. The effect of electrolyte concentrations is studied experimentally. At low electrolyte concentrations, the products of electrolysis are removed from the processing area under the action of gravity, and uniform electrodes with high aspect ratio can be prepared. At high electrolyte concentrations, intense bubble production destroys the diffusion layer around the electrode and leads to a dynamic equilibrium state, allowing the preparation of uniform wire electrodes in a rough machining process. The proposed method can prepare wire electrodes with different initial diameters. In this paper, uniform wire electrodes of length 1900 μm, diameter 7 μm, and aspect ratio 270 are fabricated by the proposed method from a tungsten wire of initial diameter 50 μm.

Modeling of microporosity formation and hydrogen concentration evolution during solidification of an Al–Si alloy**Project supported by the National Natural Science Foundation of China (Grant No. 51901148), the Fund of the State Key Laboratory of Solidification Processing (Northwestern Polytechnical University), China (Grant No. SKLSP202006), and the State Key Lab of Advanced Metals and Materials (University of Science and Technology Beijing), China

We simulate the evolution of hydrogen concentration and gas pore formation as equiaxed dendrites grow during solidification of a hypoeutectic aluminum–silicon (Al–Si) alloy. The applied lattice Boltzmann-cellular automaton-finite difference model incorporates the physical mechanisms of solute and hydrogen partitioning on the solid/liquid interface, as well as the transports of solute and hydrogen. After the quantitative validation by the simulation of capillary intrusion, the model is utilized to investigate the growth of the equiaxed dendrites and hydrogen porosity formation for an Al–(5 wt.%)Si alloy under different solidification conditions. The simulation data reveal that the gas pores favorably nucleate in the corners surrounded by the nearby dendrite arms. Then, the gas pores grow in a competitive mode. With the cooling rate increasing, the competition among different growing gas pores is found to be hindered, which accordingly increases the pore number density in the final solidification microstructure. In the late solidification stage, even though the solid fraction is increasing, the mean concentration of hydrogen in the residue melt tends to be constant, corresponding to a dynamic equilibrium state of hydrogen concentration in liquid. As the cooling rate increases or the initial hydrogen concentration decreases, the temperature of gas pore nucleation, the porosity fraction, and the mean porosity size decrease, whilst the mean hydrogen concentration in liquid increases in the late solidification stage. The simulated data present identical trends with the experimental results reported in literature.

Water Hummer Technology for Soil Destruction on Dredgers

The present investigation aims to propose a solution of the problem which is connected with slurry processing during the dredger’s operation under difficult conditions. On dredgers, depending on the degree of air dryness or low ambient temperatures very often arises technical problem that creates difficulties for the crew. It is connected with the fact that soil surface layer is very dense. It is very difficult to dredge the soil during extraction under water surface or unloading from the hold of a vessel at low ambient temperatures. The top layer of the very soil is characterized by a high degree of compaction and can be destroyed in two ways only. The first way is to use very powerful mechanical equipment (percussion mechanisms, vibration equipment, etc.). This method is associated with high energy spending and its use on a vessel is technically difficult. The second way is to use the soil cutting process with the use of mechanical cutters. Dredger’s operation with the use of milling equipment is always characterized by the fact that during soil mechanical treatment there is always occurs breakage of the cutter teeth or rapid wear of the cutting surfaces. A similar problem occurs when sandy or clay soil is extracted under water, which is compacted by its properties. In investigation a non-trivial solution was used to solve the problem of destruction of the compacted soil layer during the operation of the dredger. It was proposed to use the hydrodynamic method based on water hammer as the main mechanism for the destruction of compacted soil. As a result of the interaction of the compacted soil layer and high pressurized directed water jets, good performance of the dredger can be achieved. The two-dimensional mechanism of destruction of the compacted soil layer can be described by the condition of dynamic equilibrium of the three main flows - the jet, which flows from the conical nozzle and two flows along the soil surface. For these streams, a reactive force evaluation has been performed. Destructive jets can be generated by standard marine pumps in combination with the use of water hammer. Based on the results of the experiments, it was found that the qualitative destruction of the surface layer of compacted soil occurs using two or three phases of hydraulic water hummer.

MMCL-Net: Spinal disease diagnosis in global mode using progressive multi-task joint learning

Simultaneous detection, segmentation, and classification of multiple spinal structures on MRI is crucial for the early and pathogenesis-based diagnosis of multiple spine diseases in the clinical setting. It is more assistance for radiologists reflections on the disease based on the pathogenesis when the lesion area and its adjacent structures are detected. Obviously, the multiple structures of the spine are directly interdependent and influential, and the multi-tasks under a deep convolutional neural network framework can also influence each other. Multi-task joint optimization in the spinal global mode is a direct outlet to seek the dynamic balance of the above potential correlation. In this paper, we propose a novel end-to-end Multi-task Multi-structure Correlation Learning Network (MMCL-Net) for the detection, segmentation, and classification (normal, slight, marked, and severe) of three types of spine structure: disc, vertebra, and neural foramen simultaneously. And the model is locally optimized to achieve a more stable dynamic equilibrium state. Extensive experiments on T1/T2-weighted MR scans from 200 subjects demonstrate that MMCL-Net achieves high performance with mAP of 0.9187, the classification accuracy of 90.67%, and dice coefficient of 90.60%. The experimental results show that the performance of our method is comparable to that of the state-of-the-art methods.

О некоторых количественных закономерностях формирования урожая мидий (Mytilus galloprovincialis Lam.) на различных типах искусственных субстратов

Quantitative regularities in the formation of mussel harvest (B) on various types of artificial substrates are investigated for four substrates, varying by the collector area (S) per 1 linear meter: 0,09, 0,21, 0,34 and 0,55 sq. m. The results of mollusk cultivation on the collectors with various artificial substrate areas have shown that the dynamics of biomass (B) depends on the time of cultivation (t) and can be described by a logistic equation: Bt = B st/(1 - eb-kt). A relation between a harvest and a collector area has been identified, and this relation is approximated by a power function: B = 2,62 S1,25. It is shown that the harvest formation is mediated through the intraspecific competition for artificial substrate (life space), which is fulfilled through self-thinning; as a result, the population ends up in the state of dynamic equilibrium that corresponds to “ecological capacity” of a collector.

The development of postural control in 6-17 old years healthy children. Part II Postural control evaluation - Limits of Stability Test (LOS) in 6-17 old year children.

<b>Introduction</b>: The ability to Reach quickly to changing external stimuli, to move the body quickly and precisely in any direction and to maintain the centre of gravity above the support base, all contribute to maintaining balance in dynamic conditions. The Limits of Stability Test (LOS) provides information on the state of dynamic equilibrium in a standing position.<br> <b>Aim</b> : Assessment of dynamic postural control in developmental age.<br> <b>Material</b> : 127 healthy children (65 girls and 62 boys) aged 6 - 17years. <br> <b>Methods</b>: All children underwent LOS test (posturograph NeuroCom) with registration of reaction time (RT), movement velocity (MVL), directional control (DCL) , maximum excursion (MXE) and endpoint excursion (EPE).<br> <b>Results</b>: At the age of 6-7 years, not fully developed jumping strategy and visual feedback mechanism in the control of movement were observed. All tested parameters were significantly worse in children aged 6 - 9 years. After this period, a significant improvement in TR and MVL was observed, with no significant changes in subsequent age groups while significant improvement in MXE up to 12 , EPE and DCL up to 13 years of age was noted. No significant gender differences were fund in the LOS test parameters. <br> <b>Conclusions</b>: 1 The LOS test showed significantly lower dynamic balance development in children aged 6 - 7 years. 2 The study showed a significant improvement in all parameters of the LOS test up to 13 years of age, which supports the termination of the function at that time.

How does the structural inhomogeneity influence the shear band behaviours of metallic glasses

ABSTRACTHere we propose a model to understand the influence of structural inhomogeneity on the shear band behaviours of metallic glasses. By considering the inhomogeneous structure and stress concentration, the model predicts that the strain for shear band nucleation in metallic glasses can be variable and far below the theoretical elastic limit. During sliding, the shear band will approach a dynamic equilibrium state of balanced free volume generation and annihilation. By considering the accumulation of irreversible structure change, the shear band will finally develop into fracture. Under fluctuating load, the shear band shows an ‘activate-arrest’ behaviour, which results from a delayed response to the external load change. These results reasonably explain and correlate the physics behind the elastic limit, stick-slip shear band behaviour, implicit shear events, and shear band fracture in metallic glasses. The study can provide another perspective and platform to understand the correlations between structural inhomogeneity and shear band behaviours in metallic glasses, and further explore other shear band related phenomena not only in metallic glasses but also in the class of shear-softened materials.

Multi-factor controls on initial gas production pressure of coalbed methane wells in Changzhi-Anze block, Central-Southern of Qinshui Basin, China

Adsorption and desorption of coalbed methane are generally at a dynamic equilibrium state under the undisturbed coal reservoir. However, as the reservoir pressure drops to a certain value during the extraction of coalbed methane, the equilibrium state is destroyed and thus more coalbed methane desorbs and escapes from coal to wellbore. Here the corresponding bottom-hole fluid pressure is called initial gas production pressure (IGPP) in the development practice of coalbed methane wells. This paper, which has taken Changzhi-Anze block in the central-southern part of Qinshui basin as the study object, addresses the distribution characteristic and control factors of IGPP of coalbed methane wells and then explores the key factors affecting IGPP using grey correlation analysis theory. The results indicate that IGPP varies from 1.09 MPa to 6.57 MPa, showing a distribution law with high in the middle and low in the west and east of the study area, which presents a similar distribution characteristic with burial depth, thickness, coal rank, gas content, original reservoir pressure, and in-situ stress. Further, through grey correlation analysis, it concludes that the correlation degrees of control factors affecting IGPP of coalbed methane wells in the descending order are decline rate of working fluid level, water yield before gas production, reservoir pressure, coal thickness, coal rank, minimum horizontal principal stress, burial depth, and gas content. Among these factors, engineering factors, including decline rate of working fluid level and water yield before gas production, present a key controlling effect, because they can determine the smooth migration pathway directly during initial water production. And another key factor, original reservoir pressure also builds strong and positive correlation with IGPP under the interaction of other geology and reservoir factors, revealing the capability of gas desorption and the transmission of pressure drops.

Timing of oocyte recruitment within the ovulatory cycle of Macedonian shad, Alosa macedonica, a batch spawning fish with indeterminate fecundity

The recruitment of primary growth (PG) oocytes to the secondary growth (SG) phase within the ovulatory cycle, i.e. time interval between two sequential ovulation/spawning events, has rarely been examined in detail in a quantitative manner for batch spawning fishes with indeterminate fecundity. In the present study we analyzed the ovarian dynamics of Macedonian shad, Alosa macedonica, an iteroparous batch spawning clupeid with indeterminate fecundity, with the main goal to define the timing of PG recruitment and relate it to the ovulatory cycle. The latter was classified into four different phases (pre-ovulatory, running, post-ovulatory, intermediate) through postovulatory follicles and presence/absence of hydrated oocytes. Various indices of ovarian dynamics, including the formation and mean diameter of the advanced oocyte batch, the ovarian developmental stage, the oocyte size modality and the gonadosomatic index, varied among the ovulatory phases, evidencing cyclicity. Relative fecundity of newly recruited SG oocytes was used as an index of PG recruitment intensity and was shown to follow a specific pattern within the ovulatory cycle; PG recruitment occurred in a stepwise manner and in parallel with ovulation of the advanced oocyte batch, and synchronization of these two processes kept the ovary in a state of dynamic equilibrium.

Suburban stream erosion rates in northern Kentucky exceed reference channels by an order of magnitude and follow predictable trajectories of channel evolution

This paper documents ranges of streambed and bank erosion observed across suburban northern Kentucky via time-series surveys at 61 stream monitoring sites from the last ~10 yr. Average erosion rates in streams draining undeveloped watersheds (<5% total impervious area, TIA) were nominal: 0.5 cm/yr of incision (range of −5.8 to 11 cm/yr) and 1.0 cm/yr of widening (range of −58 to 20 cm/yr). By contrast, streams draining developed watersheds (>5% TIA) averaged 1.5 cm/yr of incision (range of −9.2 to 36 cm/yr) and 9.4 cm/yr of widening (range of −11 to 61 cm/yr). The suburban streams also followed predictable patterns of evolution consistent with the “classic” Channel Evolution Model (CEM) of Schumm et al. (1984), with the initial incision period (Stage 2) coinciding with bed coarsening followed by widening (Stage 3). Out of 45 sites draining >5% TIA, only four were in a state of dynamic equilibrium (Stage 1), two of which were attributable to stabilization via stream restoration and another was attributable to an upstream stormwater retrofit that substantially restricted erosive discharges. The other stable suburban site drained a watershed that was only 6.5% TIA and was just upstream of a reach undergoing incision and headcutting, implying that it would likely be experiencing incision (Stage 2) soon. Although the suburban sites spanned a gradient of development age and extent, >90% fell into unstable CEM categories (Stages 2 through 4), with only one site exhibiting features emblematic of potential geomorphic recovery (Stage 4 trending to Stage 5), attributable to an upstream stormwater retrofit. This case study underscores the predictable nature of long-term channel instability in gravel/cobble streams draining conventionally-developed suburban watersheds in support of more mechanistically based stormwater management strategies tailored to prevent the geomorphic degradation commonly associated with the urban stream syndrome.

Measuring and reducing the disequilibrium levels of dynamic networks with ride-sourcing vehicle data

Transportation systems are being reshaped by ride sourcing and shared mobility services in recent years. The transportation network companies (TNCs) have been collecting high-granular ride-sourcing vehicle (RV) trajectory data over the past decade, while it is still unclear how the RV data can improve current dynamic network modeling for network traffic management. This paper proposes to statistically estimate network disequilibrium level (NDL), namely to what extent the dynamic user equilibrium (DUE) conditions are deviated in real-world networks. Using the data based on RV trajectories, we present a novel method to estimate the real-world NDL measure. More importantly, we present a method to compute zone-to-zone travel time data from trajectory-level RV data. This would become a data sharing scheme for TNCs such that, while being used to effectively estimate and reduce NDL, the zone-to-zone data reveals neither personally identifiable information nor trip-level business information if shared with the public. In addition, we present an NDL based traffic management method to perform user optimal routing on a small fraction of vehicles in the network. The NDL measures and NDL-based routing are examined on two real-world large-scale networks: the City of Chengdu with trajectory-level RV data and the City of Pittsburgh with zone-to-zone travel time data. We found that, on weekdays in each city, NDLs are likely high when travel demand is high (thus when congestion is mild or heavy). Generally, a weekend midnight exhibits higher NDLs than a weekday midnight. Many NDL patterns are different between Chengdu and Pittsburgh, which are attributed to unique characteristics of both demand and supply in each city. For instance, NDL in Pittsburgh is much more stable from day to day and from hour to hour, comparing to Chengdu. In addition, we observe that origin-destination pairs with high NDLs are spatially and temporally sparse for both cities. For the Pittsburgh network, we evaluate the effectiveness of NDL-based traffic routing, which shows great potential to reduce total travel time with routing a small fraction of vehicles (1% in the experiments), even using dated NDL that is estimated in the prior hour.

Disturbances and Climate Drive Structure, Stability, and Growth in Mixed Temperate Old-growth Rainforests in the Caucasus

The Colchic rainforest of the Western Caucasus is one of the few temperate rainforests dominated by broadleaf deciduous trees. Understanding natural dynamics of broadleaf-dominated temperate rainforests is essential for their conservation and management. Here, we investigate for the first time the structure, natural disturbance, and recruitment dynamics of a mixed Colchic old-growth rainforest, dominated by Fagus orientalis and Picea orientalis. We used forest inventories and dendrochronological analysis of tree growth in five 30-m-radius plots to quantify forest structure, growth, and disturbances. For the last 400 years, the forest experienced a mixed disturbance regime dominated by frequent small gaps superimposed onto medium disturbances with about a 25-year recurrence period, with no evidences of stand-replacing disturbances. This disturbance regime favored the dominance of shade-tolerant, late successional species with slow tree canopy access through multiple growth releases. These dynamics impose low growth rates and continuous recruitment of spruce and beech, and contributed to a high heterogeneity of tree ages and sizes that result in stable forest structure, as suggested by the low stand slenderness. Spruces were the oldest (up to 427 years) and fastest growing trees in the forest, suggesting that their low presence in the forest is due to low disturbance rates that limit their recruitment. Spring climate conditions that promoted beech growth were detrimental for spruce growth, suggesting that interspecies interactions may condition the effect of climate on forest growth and development. The dynamic equilibrium state we reconstructed in this old-growth forest could likely be disrupted by anthropogenic disturbances or management.