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Pseudomonas putida is widely used in industrial applications, including the recombinant proteins production, because of its natural advantageous properties. In this study, the gene encoding FleQ, the primary regulator of flagellar synthesis, was deleted to construct a new non‐motile P. putida KT2440‐derived strain (ΔfleQ). The non‐motile cells showed reduced biofilm formation and enhanced expression of a heterologous gene in nutrient‐rich media compared with the wild‐type (WT) strain, attributed to the reallocation of cellular resources from flagellar synthesis and cellular motility. Additionally, the ΔfleQ strain exhibited enhanced tolerance to chloramphenicol, indicating higher ribosome production, confirmed by a higher RNA/protein ratio relative to the WT. While the WT strain showed decreased growth and a three‐fold increase in reporter gene activity in minimal media, the ΔfleQ strain maintained consistent reporter gene expression and exhibited a relatively higher growth rate. This suggests that the FleQ is involved in modulating proteome allocation based on nutrient quality. The removal of FleQ allows for more flexible resource allocation, creating a chassis strain with nutrient quality‐independent gene expression capacity, which could be valuable in industrial applications where consistent output is essential. [ABSTRACT FROM AUTHOR]

This study investigates the growth of an avascular tumour described through the interchange of mass among its constituents and the production of inelastic distortions induced by growth itself. A key contribution of this research examines the role of non-local diffusion arising from the complex and heterogeneous tumour micro-environment. In our context, the non-local diffusion is enhanced by a variable-order fractional operator that incorporates crucial information about regions of limited nutrient availability within the tissue. Our research also focuses on the identification of an evolution law for the growth-induced inelastic distortions recast through the identification of non-conventional forces dual to suitable kinematic descriptors associated with the growth tensor. The establishment of such evolution law stems from examining the dissipation inequality and subsequently determining a posteriori connections between the inelastic distortions and the source/sink terms in the mass balance laws. To gain insights into the dynamics of tumour growth and its response to the proposed modelling framework, we first study how the variables governing the tissue evolution are affected by the introduction of the new growth law. Second, we investigate how regions of limited diffusion within the tumour, encoded into a fractional operator of variable-order, influence its growth. [ABSTRACT FROM AUTHOR]

The effect of dosage of recycled aggregate from construction waste on the mechanical strength of cement stabilized macadam (CSM) was investigated, the optimal dosage and proportion of recycled aggregate were proposed based on the principle of the highest strength or the maximum dosage. The growth law of mechanical strength of cement stabilized macadam recycled aggregate ( CSMRA) was investigated under the optimal dosage, a prediction model of mechanical strength of CSMRA was proposed, and the reliability of prediction was verified. The results show that the compressive strength of CSMRA increases and then decreases with the increase of recycled fine aggregate dosage, decreases with the increase of recycled coarse aggregate dosage, and the maximum dosage of recycled aggregate is 70% (mass fraction). The correlation coefficient of established mechanical strength growth equation and prediction model is more than 0. 98, and the error between predicted value and measured value is no more than 14. 0%. This indicates that the model can accurately predict the mechanical strength of CSMRA at other ages after determining cement dosage, aggregate type, mineral proportion and 7 d strength. [ABSTRACT FROM AUTHOR]

Soft tissue growth is crucial across various physiological applications, with mathematical modelling playing a pivotal role in understanding the underlying processes. The volumetric growth theory serves as a commonly used mathematical framework in this context. Our previous research on volumetric growth theory primarily concentrated on defining the incremental growth tensor in loaded and stressed configurations, revealing that this approach closely aligns with experimental observations of residual hoop stress distribution. However, given the assumptions employed, the approach has limitations in accurately predicting the growth timeline. In this work, we address these issues by incorporating the effect of initial residual strain and introducing a new mixed trigger growth evolution law. In this growth law, we do not use growth saturation as an upper limit, as this assumption cannot represent many physiological conditions. Instead, we propose that growth in soft tissues leads to a new equilibrium state. To illustrate this idea, we introduce a growth incompatibility function, denoted as I. We establish the analytical relationship between I and the opening angle in a simplified cylindrical geometry resembling the structure of the heart or arteries. We put forth a revised growth law that is both stress and incompatibility driven/Our results show that by using this mixed trigger growth law, tissues will not grow indefinitely. Instead, a stress-driven homeostasis incompatibility state will be reached. In addition, by accounting for the initial opening angle in the model, we can accurately trace the growth history of the heart, aligning with experimental data obtained from measuring the opening angle in young pigs from birth to maturity. [ABSTRACT FROM AUTHOR]

The conventional petroleum field in Jiyang Depression has always been the main battlefield of exploration and development in Shengli Oilfield. It has experienced more than 60 years of exploration and development and entered the mature exploration stage as a whole， but it still has a relatively large scale of reserve increase every year， which is not consistent with the traditional growth trend of proven petroleum-in-place in oil and gas-bearing basins. The critical issues concerning the exploration decisions of Shengli Oilfield need to be clarified urgently， including the growth law of the conventional proven petroleum-in-place in Jiyang Depression， the strong trend of reserve increase， and the main fields for reserve increase. By analyzing the exploration process of Jiyang Depression， the geological characteristics， resource conditions， exploration investment， theory and technology， resource sequence， and other exploration elements were analyzed， revealing the exploration discovery law of conventional petroleum in Jiyang Depression. The broom-shaped model prediction method and proven rate method of resource were used to predict the growth trend of conventional proven petroleum-in-place. The scale and favorable direction of future reserve increase of conventional petroleum in Jiyang Depression were clarified by analyzing the main fields with reserve increase. The results show that the complex geological characteristics of Jiyang Depression and the relatively abundant remaining resources determine the diversity of exploration objects， the tortuosity of the exploration process， and the long-term nature of exploration history. The conventional petroleum in Jiyang Depression can still maintain a long period of stable reserve increase under conditions of ensuring a relatively stable exploration investment， continuing to innovate the exploration theory and key technologies， and maintaining a relatively reasonable resource sequence. Jiyang Depression can still produce about 2.5 × 108 t of conventional proven petroleum-in-place in the next 10 years under the current economic and technical conditions and the relative guarantee of exploration investment. It is pointed out that the Neogene river sandstone reservoir， lithologic oil and gas reservoirs in the Upper Submember of the 4th Member of the Eocene Shahejie Formation（Es4U）-the Lower 3rd Member of the Eocene Shahejie Formation（Es3L）， and other mature fields are still the ballast stones for stable reserve increase. Kongdian Formation-the deep field of the Lower Submember of the 4th Member of the Eocene Shahejie Formation（Es4L） is an essential field for large-scale reserve increase， and the pre-Paleogene buried hill is a favorable direction for the petroleum enrichment and high yield. In the future， the exploration progress in the unconventional and new energy fields should be closely tracked， and the research results of the growth law and the reserve increase trend of conventional proven petroleum-in-place in Jiyang Depression should be constantly improved and revised to make them more conform to the development trend of oilfield exploration and guide the oilfield exploration decisions.

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Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Many cellular activities in bacteria are organized according to their growth rate. The notion that ppGpp measures the cell’s growth rate is well accepted in the field of bacterial physiology. However, despite decades of interrogation and the identification of multiple molecular interactions that connects ppGpp to some aspects of cell growth, we lack a system-level, quantitative picture of how this alleged “measurement” is performed. Through quantitative experiments, we show that the ppGpp pool responds inversely to the rate of translational elongation in Escherichia coli. Together with its roles in inhibiting ribosome biogenesis and activity, ppGpp closes a key regulatory circuit that enables the cell to perceive and control the rate of its growth across conditions. The celebrated linear growth law relating the ribosome content and growth rate emerges as a consequence of keeping a supply of ribosome reserves while maintaining elongation rate in slow growth conditions. Further analysis suggests the elongation rate itself is detected by sensing the ratio of dwelling and translocating ribosomes, a strategy employed to collapse the complex, high-dimensional dynamics of the molecular processes underlying cell growth to perceive the physiological state of the whole.

The growth law, electronic properties and spectra of Fenλ (n = 2–18; λ = 0, ±1) clusters have been examined by density functional theory (DFT) and an unbiased structure prediction method. Extensive geometry optimizations have been executed and show that the global minimum structures of Fenλ clusters have a distinct growth law when n is 8–18. For n = 8–13 and 14–18, the iron atoms grow around a decahedral and icosahedral iron cluster core, respectively. Based on the present ground states, the calculated electronic parameters are in line with the experimental values. The thermal stability of charged iron cluster is higher than that of neutral iron cluster. The octahedral and icosahedral clusters are more stable than their neighbors. The former has low chemical activity and may be a superatom. The magnetic moment of Fe atom weakens in the cluster. The UV spectra, photoelectron spectra (PES) and infrared and Raman spectra of the Fenλ clusters have been predicted and the global minimum structures of the Fen− clusters are determined by comparing the theoretical PES with the experimental results. [ABSTRACT FROM AUTHOR]

Cancer cells, like microbes, live in complex metabolic environments. Recent evidence suggests that microbial behavior across metabolic environments is well described by simple empirical growth relationships, or growth laws. Do such empirical growth relationships also exist in cancer cells? To test this question, we develop a high-throughput approach to extract quantitative measurements of cancer cell behaviors in systematically altered metabolic environments. Using this approach, we examine relationships between growth and three frequently studied cancer phenotypes: drug-treatment survival, cell migration, and lactate overflow. Drug-treatment survival follows simple linear growth relationships, which differ quantitatively between chemotherapeutics and EGFR inhibition. Cell migration follows a weak grow-and-go growth relationship, with substantial deviation in some environments. Finally, lactate overflow is mostly decoupled from growth rate and is instead determined by the cells' ability to maintain high sugar uptake rates. Altogether, this work provides a quantitative approach for formulating empirical growth laws of cancer.

ABSTRACT Understanding the allocation of the cellular proteome to different cellular processes is central to unraveling the organizing principles of bacterial physiology. Proteome allocation to protein translation itself is maximally efficient, i.e., it represents the minimal allocation of dry mass able to sustain the observed protein production rate. In contrast, recent studies on bacteria have demonstrated that the concentrations of many proteins exceed the minimal level required to support the observed growth rate, indicating some heterogeneity across pathways in their proteome efficiency. Here, we systematically analyze the proteome efficiency of metabolic pathways, which together account for more than half of the Escherichia coli proteome during exponential growth. Comparing the predicted minimal and the observed proteome allocation to different metabolic pathways across growth conditions, we find that the protein abundance in the most costly biosynthesis pathways—those for amino acid biosynthesis and cofactor biosynthesis—is regulated for near-optimal efficiency. Overall, proteome efficiency increases along the carbon flow through the metabolic network; proteins involved in pathways of nutrient uptake and central metabolism tend to be highly over-abundant, while proteins involved in anabolic pathways and in protein translation are much closer to the expected minimal abundance across conditions. Our work thus provides a bird’s-eye view of metabolic pathway efficiency, demonstrating systematic deviations from optimal cellular efficiency at the network level. IMPORTANCE Protein translation is the most expensive cellular process in fast-growing bacteria, and efficient proteome usage should thus be under strong natural selection. However, recent studies show that a considerable part of the proteome is unneeded for instantaneous cell growth in Escherichia coli. We still lack a systematic understanding of how this excess proteome is distributed across different pathways as a function of the growth conditions. We estimated the minimal required proteome across growth conditions in E. coli and compared the predictions with experimental data. We found that the proteome allocated to the most expensive internal pathways, including translation and the synthesis of amino acids and cofactors, is near the minimally required levels. In contrast, transporters and central carbon metabolism show much higher proteome levels than the predicted minimal abundance. Our analyses show that the proteome fraction unneeded for instantaneous cell growth decreases along the nutrient flow in E. coli.

Organism growth is often determined by multiple resources interdependently. However, growth models based on the Droop cell quota framework have historically been built using threshold formulations, which means they intrinsically involve single-resource limitations. In addition, it is a daunting task to study the global dynamics of these models mathematically, since they employ minimum functions that are non-smooth (not differentiable). To provide an approach to encompass interactions of multiple resources, we propose a multiple-resource limitation growth function based on the Droop cell quota concept and incorporate it into an existing producer–grazer model. The formulation of the producer's growth rate is based on cell growth process time-tracking, while the grazer's growth rate is constructed based on optimal limiting nutrient allocation in cell transcription and translation phases. We show that the proposed model captures a wide range of experimental observations, such as the paradox of enrichment, the paradox of energy enrichment, and the paradox of nutrient enrichment. Together, our proposed formulation and the existing threshold formulation provide bounds on the expected growth of an organism. Moreover, the proposed model is mathematically more tractable, since it does not use the minimum functions as in other stoichiometric models. [ABSTRACT FROM AUTHOR]

Prolonged cell cycle arrests occur naturally in differentiated cells and in response to various stresses such as nutrient deprivation or treatment with chemotherapeutic agents. Whether and how cells survive prolonged cell cycle arrests is not clear. Here, we used S. cerevisiae to compare physiological cell cycle arrests and genetically induced arrests in G1-, meta- and anaphase. Prolonged cell cycle arrest led to growth attenuation in all studied conditions, coincided with activation of the Environmental Stress Response (ESR) and with a reduced ribosome content as determined by whole ribosome purification and TMT mass spectrometry. Suppression of the ESR through hyperactivation of the Ras/PKA pathway reduced cell viability during prolonged arrests, demonstrating a cytoprotective role of the ESR. Attenuation of cell growth and activation of stress induced signaling pathways also occur in arrested human cell lines, raising the possibility that the response to prolonged cell cycle arrest is conserved.

Nitride film as a hydrogen permeation barrier on zirconium hydride has seldom been studied. In this work, the zirconium nitride films were prepared on zirconium hydride in an atmosphere of N2 and N2 + H2 at 500~800 °C, with a holding time of 5 h and 20 h, and the mechanisms of film growth and hydrogen permeation were analyzed. The results showed that the film growth was mostly influenced by the temperature, followed by the reaction atmosphere and the holding time. The hydrogen could increase the nitrogen diffusivity during the formation of zirconium nitride films. The in situ nitriding conditions were optimized as 800 °C, N2 + H2 atmosphere, and 5~20 h. The chemical composition of ZrN-based films was mainly comprised of Zr and N, with a minor content of O. In addition, the film exhibited a major phase of ZrN, accompanied by the coexistence of ZrO2, ZrO, ZrN(NH2), and ZrN0.36H0.8, as well as O-H and N-H bonds based on the XPS analysis. The as-prepared ZrN base films in the present study exhibited superior hydrogen permeation resistance to other ZrO2 films previously reported. The hydrogen permeation resistance of the films could be attributed to the following mechanisms, including the chemical capture of hydrogen by the above-mentioned compounds and bonds; the physical barrier of continuous and dense film incurred from the volume effect of different compounds based on Pilling–Bedworth model and the different nitrogen diffusion coefficients at different temperatures. [ABSTRACT FROM AUTHOR]

Many organisms maintain generalized stress responses activated by adverse conditions. Although details vary, a common theme is the redirection of transcriptional and translational capacity away from growth-promoting genes and toward defense genes. Yet the precise roles of these coupled programs are difficult to dissect. Here we investigated Saccharomyces cerevisiae responding to salt as a model stressor. We used molecular, genomic, and single-cell microfluidic methods to examine the interplay between transcription factors Msn2 and Msn4 that induce stress-defense genes and Dot6 and Tod6 that transiently repress growth-promoting genes during stress. Surprisingly, loss of Dot6/Tod6 led to slower acclimation to salt, whereas loss of Msn2/4 produced faster growth during stress. This supports a model where transient repression of growth-promoting genes accelerates the Msn2/4 response, which is essential for acquisition of subsequent peroxide tolerance. Remarkably, we find that Msn2/4 regulate DOT6 mRNA production, influence Dot6 activation dynamics, and are required for full repression of growth-promoting genes. Thus, Msn2/4 directly regulate resource reallocation needed to mount their own response. We discuss broader implications for common stress responses across organisms., Competing Interests: CONFLICT OF INTEREST STATEMENT The authors declare that they have no conflict of interest.

The lack of precise equilibrium gas permeability affects the application of edible coatings. This study aims to precisely control the coating oxygen permeability through layer-by-layer (LbL) assembly. The coatings fabricated by chitosan (CS) and sodium alginate (SA) were systematically investigated about assembly mechanism, growth law, barrier performance, and application. Results showed that coating assembly was driven by the electrostatic interaction between CS and SA. The fastest coating growth was the pH of SA and CS at 4 and the NaCl concentration at 0.1 mol/L. The coating with a specific barrier performance had been proved to be accurately fabricated by adjusting the assembly concentration and times. Finally, coating combinations with the desired oxygen-barriers for strawberries, tangerines, and bananas were predicted based on the gas exchange model and fabricated by LbL. The physiological properties of the coated fruits indicated that the optimal LbL coating extended the shelf life of strawberries, tangerines and bananas by 2, 4, and 4 days, respectively. This research may help to precisely control the properties of coatings during the preparation and application of edible coatings. [ABSTRACT FROM AUTHOR]

The structures and spectra of Cu n b (n = 3–16; b = 0, ±1) clusters have been researched by means of density functional theory (DFT) coupled with CALYPSO structure prediction method. It is found that the growth of Cu n (n = 9–16) clusters shows a clear regularity. Based on the global minimum structure of the Cu n cluster, the UV spectra have been predicted and are in good agreement with the available experimental results. The most stable structures of anionic copper clusters have been identified by comparing experimental and theoretical photoelectron spectra (PES). The infrared (IR) and Raman spectra of cationic copper clusters have been simulated and the calculated IR spectra of Cu n + -Ar m (n = 3–10) complexes are in accord with experimental spectra. The Ar atoms adsorbed to small Cu n + cluster have partly influence on the IR spectrum of the host cluster. The Cu 6 , Cu 8 and Cu 3 + clusters can be regard as three magic clusters. [ABSTRACT FROM AUTHOR]

Many cellular activities in bacteria are organized according to their growth rate. The notion that ppGpp measures the cell's growth rate is well accepted in the field of bacterial physiology. However, despite decades of interrogation and the identification of multiple molecular interactions that connects ppGpp to some aspects of cell growth, we lack a system-level, quantitative picture of how this alleged "measurement" is performed. Through quantitative experiments, we show that the ppGpp pool responds inversely to the rate of translational elongation in Escherichia coli. Together with its roles in inhibiting ribosome biogenesis and activity, ppGpp closes a key regulatory circuit that enables the cell to perceive and control the rate of its growth across conditions. The celebrated linear growth law relating the ribosome content and growth rate emerges as a consequence of keeping a supply of ribosome reserves while maintaining elongation rate in slow growth conditions. Further analysis suggests the elongation rate itself is detected by sensing the ratio of dwelling and translocating ribosomes, a strategy employed to collapse the complex, high-dimensional dynamics of the molecular processes underlying cell growth to perceive the physiological state of the whole. [ABSTRACT FROM AUTHOR]

The growth and remodelling of soft tissues plays a significant role in many physiological applications, particularly in understanding and managing many diseases. A commonly used approach for soft tissue growth and remodelling is volumetric growth theory, introduced in the framework of finite elasticity. In such an approach, the total deformation gradient tensor is decomposed so that the elastic and growth tensors can be studied separately. A critical element in this approach is to determine the growth tensor and its evolution with time. Most existing volumetric growth theories define the growth tensor in the reference (natural) configuration, which does not reflect the continuous adaptation processes of soft tissues under the current configuration. In a few studies where growth from a loaded configuration was considered, simplifying assumptions, such as compatible deformation or geometric symmetries, were introduced. In this work, we propose a new volumetric growth law that depends on fields evaluated in the current configuration, which is residually stressed and loaded, without any geometrical restrictions. We illustrate our idea using a simplified left ventricle model, which admits inhomogeneous growth in the current configuration. We compare the residual stress distribution of our approach with the traditional volumetric growth theory, that assumes growth occurring from the natural reference configuration. We show that the proposed framework leads to qualitative agreements with experimental measurements. Furthermore, using a cylindrical model, we find an incompatibility index that explains the differences between the two approaches in more depth. We also demonstrate that results from both approaches reach the same steady solution published previously at the limit of a saturated growth. Although we used a left ventricle model as an example, our theory is applicable in modelling the volumetric growth of general soft tissues. [ABSTRACT FROM AUTHOR]

The entropy production per unit time is calculated for the regular lamellae -, and for the regular rods formation, respectively. The entropy production is a function of some parameters which define the eutectic phase diagram, coefficient of the diffusion in the liquid, and some capillary parameters connected with the mechanical equilibrium located at the triple point of the solid/liquid interface. Minimization of the entropy production allowed to formulate mathematically the so-called Growth Law for both envisaged eutectic morphologies.

The quality and the stability of devices prepared from polycrystalline layers of organic–inorganic perovskites highly depend on the grain sizes prevailing. Tuning of the grain size is either done during layer preparation or in a post-processing step. Our investigation refers to thermal imprint as the post-processing step to induce grain growth in perovskite layers, offering the additional benefit of providing a flat surface for multi-layer devices. The material studied is MAPbBr3; we investigate grain growth at a pressure of 100 bar and temperatures of up to 150 °C, a temperature range where the pressurized stamp is beneficial to avoid thermal degradation. Grain coarsening develops in a self-similar way, featuring a log-normal grain size distribution; categories like 'normal' or 'secondary' growth are less applicable as the layers feature a preferential orientation already before imprint-induced grain growth. The experiments are simulated with a capillary-based growth law; the respective parameters are determined experimentally, with an activation energy of Q ≈ 0.3 eV. It turns out that with imprint as well the main parameter relevant to grain growth is temperature; to induce grain growth in MAPbBr3 within a reasonable processing time a temperature of 120 °C and beyond is advised. An analysis of the mechanical situation during imprint indicates a dominance of thermal stress. The minimization of elastic energy and surface energy together favours the development of grains with (100)-orientation in MaPbBr3 layers. Furthermore, the experiments indicate that the purity of the materials used for layer preparation is a major factor to achieve large grains; however, a diligent and always similar preparation of the layer is equally important as it defines the pureness of the resulting perovskite layer, intimately connected with its capability to grow. The results are not only of interest to assess the potential of a layer with respect to grain growth when specific temperatures and times are chosen; they also help to rate the long-term stability of a layer under temperature loading, e.g. during the operation of a device. [ABSTRACT FROM AUTHOR]

How cells maintain a stable size has fascinated scientists since the beginning of modern biology, but has remained largely mysterious. Recently, however, the ability to analyze single bacteria in real time has provided new, important quantitative insights into this long-standing question in cell biology.

Oxygen-rich ZrTiAlV alloy reinforced by spherulite ZrO phase was prepared by in-situ semi-solid processing. The results of high temperature (500°C) mechanical properties test confirmed that alloy elongation after semi-solid processing at 1500°C was close to that for the as-forged material, whereas yield and tensile strength were increased by 66.4% and 30.8%, respectively. SEM and EBSD results confirm that morphology selection of non-equilibrium growth is mainly controlled by the initial core shape, with dendrites always growing along the <110> direction following the Twin-Plane-Reentrant-Edge mechanism. Improved alloy strength is attributed to fine grain strengthening and precipitation strengthening caused by the ZrO phase, and α phase spheroidization ensures alloy plasticity. We also propose a crack deflection toughening mechanism for the alloy. • An oxygen-rich ZrTiAlV alloy with ZrO reinforced phase was prepared by a new in-situ semi-solid process. • The growth law of ZrO phase was determined by related characterization techniques. • The strengthening and toughening mechanism and fracture mechanism of the alloy after in-situ semi-solid treatment were clarified. [ABSTRACT FROM AUTHOR]

In order to systematically study the growth law of Catalpa brmgei and determine its fast - growing period and the optimal growth model, the Catalpa brmgei trees, aged from 18a to 37a, were selected as the research object in Luoning County of Henan Province. The growth data of trees was obtained through stem analysis, and a series of models were applied to fit growth process of tree height, diameter breast height ( DBH ) and volume, and the optimal growth model of Catalpa brmgei was screened. The results showed:

"Planting conifer and reserving broadleaved tree" is an effective way to restore broad-leaved pine forest of temperate zone in Northeast China. Liberation cutting can promote the growth of Korean pine ( Pinus koraiensis ) under forest crown and accelerate the succession. However, how liberation cutting intensity affects the growth of Korean pine in secondary forest is still unclear. Taking the "Planting conifer and reserving broadleaved tree" Korean pine forest in Changbai Mountain as the object, we constructed a growth model of diameter at breast height (DBH) and tree height of Korean pine with double dummy variables (liberation cutting intensity and tree classification) to predict the growth of Korean pine plantation under different liberation cutting intensities, i.e . control (no liberation cutting), light-intensity liberation cutting (retaining upper canopy closure 0.6), medium-intensity liberation cutting (0.4), heavy-intensity liberation cutting (0.2) and clear cutting (cutting all upper broadleaf trees) stands. We analyzed the effects of liberation cutting intensities on DBH, tree height, and the ratio of tree height to DBH. The results showed that among six theoretical growth equations, the Gompertz model on the DBH ( R 2 =0.46) and tree height ( R 2 =0.81) was optimal basic model. The R 2 of the DBH model was increased to 0.65 and 0.89, respectively, after the single dummy variable and the double dummy variable were introduced into the basic model, while the R 2 of the tree height model was increased to 0.84 and 0.94. Therefore, the double dummy variable model was the most suitable for predicting the growth of Korean pine. The growth of DBH of pressed tree increased with the increases of liberation cutting intensity (increase by 145.8%-933.3%) during the whole simulation period (0-80 a). Average and dominant trees showed the same pattern at 42 and 60 a. In the early and middle stages of liberation cutting (20 and 42 a), clear cutting and heavy-intensity liberation cutting had similar effects on the height growth of dominant trees (64.8%-68.5%), average trees (100.0%-144.2%), and pressed trees (138.5%-183.9%). The effects of medium-intensity liberation cutting and light-intensity liberation cutting on the height growth were similar (24.3%-35.1%, 56.0%-92.3%, 84.6%-103.2%). While in the middle and late period (42 and 80 a), height growth of three grade trees increased with the increases of liberation cutting intensity. Under each liberation cutting intensity, the ratio of height to DBH of the dominant, average, and pressed trees increased successively, ranging from 0.50-0.95, 0.64-1.23, and 0.73-4.33, respectively. Only the pressed tree decreased with the increases of liberation cutting intensity at 0-80 a. Therefore, about 40 years after the implementation of liberation cutting, the promoting effect of different liberation cutting intensities on DBH growth was significantly weakened, the promoting effect on tree height growth was significantly enhanced, and the ratio of tree height to diameter began to increase. In order to alleviate forest competition, second liberation cutting should be carried out for light-intensity liberation cutting and medium-intensity liberation cutting stands to further release the growth potential of Korean pine, and thinning management should be carried out in clear cutting and heavy-intensity liberation cutting stands.

The Structural Peclet Number has been estimated experimentally by analyzing the morphology of the continuously cast brass ingots. It allowed to adapt a proper development of the Ivantsov’s series in order to formulate the Growth Law for the columnar structure formation in the brass ingots solidified in stationary condition. Simultaneously, the Thermal Peclet Number together with the Biot, Stefan, and Fourier Numbers is used in the model describing the heat transfer connected with the so-called contact layer (air gap between an ingot and crystallizer). It lead to define the shape and position of the s/l interface in the brass ingot subjected to the vertical continuous displacement within the crystallizer (in gravity). Particularly, a comparison of the shape of the simulated s/l interface at the axis of the continuously cast brass ingot with the real shape revealed at the ingot axis is delivered. Structural zones in the continuously cast brass ingot are revealed: FC - fine columnar grains, C - columnar grains, E - equiaxed grains, SC - single crystal situated axially.

The entropy production per unit time is calculated for the regular lamellae -, and for the regular rods formation, respectively. The entropy production is a function of some parameters which define the eutectic phase diagram, coefficient of the diffusion in the liquid, and some capillary parameters connected with the mechanical equilibrium located at the triple point of the solid/liquid interface. Minimization of the entropy production allowed to formulate mathematically the so-called Growth Law for both envisaged eutectic morphologies. [ABSTRACT FROM AUTHOR]

Some experiments dealing with the isothermal hot dip galvanizing were carried out. The (Zn) – coating settled on the Armco-iron substrate were examined after arresting the solidification for different periods of time. The measurement of the thickness of each sub-layer in the coating were performed due to the SEM – analysis. The zinc segregation on the cross-section of the studied sub-layers were also determined by the EDS technique. The growth laws are formulated mathematically for each of the observed sub-layer. The mechanism of the sub-layer formation is also analysed due to the observation of the birth/nucleation of the phases in the sub-layers and the effect of flux onto the sub-layers morphology formation. The appearance of each phase is referred to the Fe-Zn diagram for stable equilibrium according to which these phases are the products of the adequate peritectic transformation.

The longer cells stay in particular phases of the cell cycle, the longer it will take these cell populations to increase. However, the above qualitative description has very little predictive value, unless it can be codified mathematically. A quantitative relation that defines the population doubling time (Td) as a function of the time eukaryotic cells spend in specific cell cycle phases would be instrumental for estimating rates of cell proliferation and for evaluating introduced perturbations. Here, we show that in human cells, the length of the G1 phase (TG1) regressed on Td with a slope of ≈0.75, while in the yeast Saccharomyces cerevisiae, the slope was slightly smaller, at ≈0.60. On the other hand, cell size was not strongly associated with Td or TG1 in cell cultures that were proliferating at different rates. Furthermore, we show that levels of the yeast G1 cyclin Cln3p were positively associated with rates of cell proliferation over a broad range, at least in part through translational control mediated by a short upstream ORF (uORF) in the CLN3 transcript. Cln3p was also necessary for the proper scaling between TG1 and Td. In contrast, yeast lacking the Whi5p transcriptional repressor maintained the scaling between TG1 and Td. These data reveal fundamental scaling relationships between the duration of eukaryotic cell cycle phases and rates of cell proliferation, point to the necessary role of Cln3p in these relationships in yeast, and provide a mechanistic basis linking Cln3p levels to proliferation rates and the scaling of G1 with doubling time. [ABSTRACT FROM AUTHOR]

Summary It is generally assumed that the allocation and synthesis of total cellular resources in microorganisms are uniquely determined by the growth conditions. Adaptation to a new physiological state leads to a change in cell size via reallocation of cellular resources. However, it has not been understood how cell size is coordinated with biosynthesis and robustly adapts to physiological states. We show that cell size in Escherichia coli can be predicted for any steady-state condition by projecting all biosynthesis into three measurable variables representing replication initiation, replication-division cycle, and the global biosynthesis rate. These variables can be decoupled by selectively controlling their respective core biosynthesis using CRISPR interference and antibiotics, verifying our predictions that different physiological states can result in the same cell size. We performed extensive growth inhibition experiments, and we discovered that cell size at replication initiation per origin, namely the initiation mass or unit cell, is remarkably invariant under perturbations targeting transcription, translation, ribosome content, replication kinetics, fatty acid and cell wall synthesis, cell division, and cell shape. Based on this invariance and balanced resource allocation, we explain why the total cell size is the sum of all unit cells. These results provide an overarching framework with quantitative predictive power over cell size in bacteria. [ABSTRACT FROM AUTHOR]

Our aim in future is to computer simulate the mechanical stimulated postnatal heart development (normal growth, heart hypertrophy, etc.). We are now interested in the study of the form of growth law [1], which we could use for the simulation. We follow the theory of volumetric growth in [1]. This theory is based on the theory of generalized continuum [2] and describes the volumetric growth of tissue from macroscopic point of view.

Cellular populations in both nature and the laboratory are composed of phenotypically heterogeneous individuals that compete with each other resulting in complex population dynamics. Predicting population growth characteristics based on knowledge of heterogeneous single-cell dynamics remains challenging. By observing groups of cells for hundreds of generations at single-cell resolution, we reveal that growth noise causes clonal populations of Escherichia coli to double faster than the mean doubling time of their constituent single cells across a broad set of balanced-growth conditions. We show that the population-level growth rate gain as well as age structures of populations and of cell lineages in competition are predictable. Furthermore, we theoretically reveal that the growth rate gain can be linked with the relative entropy of lineage generation time distributions. Unexpectedly, we find an empirical linear relation between the means and the variances of generation times across conditions, which provides a general constraint on maximal growth rates. Together, these results demonstrate a fundamental benefit of noise for population growth, and identify a growth law that sets a "speed limit" for proliferation. [ABSTRACT FROM AUTHOR]

Water soluble semiconductor nanoparticles (NPs) of CdS are prepared at room temperature (~295 K) and under short time ultrasonic irradiation. We present the effect of ultrasonic irradiation on the formation of CdS NPs, and the data is explained by a growth law. It is found that the growth is governed by surface diffusion at the solid-liquid interface. CdS NPs are easily coated with relatively wide bandgap semiconductor ZnS. The interaction of core/shell CdS/ZnS NPs with a different amount of lyophilisates of human serum is studied by means of the absorption spectrum and zeta potential. [ABSTRACT FROM AUTHOR]

Abstract: A new multiphase lattice Boltzmann model based on the cascaded collision operator is developed to study the spinodal decomposition of critical quenches in the inertial hydrodynamic regime. The proposed lattice Boltzmann model is able to investigate simulations of multiphase spinodal decomposition with a very high Reynolds number. The law governing the growth of the average domain size, i.e. , is studied numerically in the late-time regime, when multiple immiscible fluids are considered in the spinodal decomposition. It is found numerically that the growth exponent, , is inversely proportional to the number, , of immiscible fluids in the system. In fact, is a simple law that matches the numerical results very well, even up to . As the number of immiscible fluids increases, the corresponding drop in the connectivity of the various fluid domains is believed to be the main factor that drives and slows down the growth rate. Various videos that accurately demonstrate spinodal decomposition with different transport mechanisms are provided (see Appendix A). The remarks and statement made in this research are based on the analysis of 5120 numerical simulations and the postprocessing of about 3.5 TB of data. [Copyright &y& Elsevier]

In this paper, we perform an analysis of bacterial cell-cycle models implementing different strategies to coordinately regulate genome replication and cell growth dynamics. It has been shown that the problem of coupling these processes does not depend directly on the dynamics of cell volume expansion, but does depend on the type of cell growth law. Our analysis has distinguished two types of cell growth laws, "exponential" and "linear", each of which may include both exponential and linear patterns of cell growth. If a cell grows following a law of the "exponential" type, including the exponential V(t) = V0 exp(kt) and linear V(t) = V0(1 + kt) dynamic patterns, then the cell encounters the problem of couphng growth rates and replication. It has been demonstrated that to solve the problem, it is sufficient for a cell to have a repressor mechanism to regulate DNA rephcation initiation. For a cell expanding its volume by a law of the "linear" type, including exponential V(t) = V0 + V1 exp (kt) and linear V(t) = V0 + kt dynamic patterns, the problem of coupling growth rates and replication does not exist. In other words, in the context of the coupling problem, a repressor mechanism to regulate DNA rephcation, and cell growth laws of the "linear" type displays the attributes of universality. The repressor-type mechanism allows a cell to follow any growth dynamic pattern, while the "linear" type growth law allows a cell to use any mechanism to regulate DNA replication. [ABSTRACT FROM AUTHOR]

Abstract: A solution of the problem of calculating the volume fraction of a phase growing by a diffusion-type law is given. This is meant that the growth velocity of a nucleus is a decreasing function of its radius R. The growth law , n >1, is employed for demonstrative calculations. The solution is obtained in the framework of the classical Johnson–Mehl–Avrami approach which uses the concept of non-physical phantom nuclei. Probabilistic treatment of this approach is offered and the necessity of phantom nuclei is confirmed. The Johnson–Mehl–Avrami approach is compared with Kolmogorov''s method and its extension — the differential critical-region method; the latter yields the same equations for the volume fraction. In the case of the growth law considered, phantom nuclei contribute to the incrementing of the transformed volume fraction. The obtained equations for the volume fraction are shown to cancel this contribution; hence they yield the true value of this quantity. Two successive approximations for the volume fraction are considered analytically and the numerical evaluation of the effect of phantom nuclei is given for different values of n. [Copyright &y& Elsevier]

We present a kinetic model describing the growth of eukaryotic cells or, more specifically, the dependence of the cell volume on time in terms of the global interplay of the mRNA and protein synthesis and degradation and lipid synthesis. Addressing two long-standing questions in this interdisciplinary field, we explain why the average protein concentration in growing cells is nearly constant and the growth can accurately be fitted by using a bilinear or exponential function. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate the effect of rigid second phases on grain growth of a matrix phase. For this purpose, variable mixtures of norcamphor as the matrix phase, with glass beads (0.08–0.51 volume fraction) as second phase, were used to perform see-through rock-analogue experiments under static conditions at constant temperatures (50°C). Irrespective of the second-phase content, grain-size evolution of all mixtures can be subdivided into a stage of continuous grain growth, a transient stage and a stage of a finally stabilized grain size. On the grain-scale, the second phases affect the migrating grain boundaries either by pinning by single particles, by multiple particles or even by particle clusters. Summed up over the entire aggregate, these pinning regimes affect the average bulk grain size of the matrix grains, such that the changes in matrix grain size directly correlate with the amount of second phases, their dispersion and their degree of clustering. In this way, the matrix grain size decreases with increasing second-phase content, which can be expressed as a Zener relationship. Originating from the modification of an ordinary grain growth law, a new mathematical expression is defined, which allows the calculation of changes in the matrix grain size as a function of different second-phase volume fractions and particle sizes. Such models will be helpful in the future to predict microstructural changes in polymineralic rocks at depth. [ABSTRACT FROM AUTHOR]

Abstract: In previous works, the authors have addressed the chemo-mechanical couplings that control much of the behaviour of many geological materials and biological tissues. The analyses accounted for deformation, mass transfer and generalized diffusion. Simulations of initial and boundary value problems involving equilibrium and transient ionic replacements have been performed via the finite element method. The thermodynamic framework underlying these developments has not been published yet and it is described here. The crux of the paper is to aggregate the phenomenon of growth to the previous models. For that purpose, the mixture system is considered thermodynamically open. The contributions, by the surroundings, to the balances of mass, momentum, energy and entropy of each species of the mixture, and of the mixture as a whole, are systematically accounted for. Previous studies in single phase solids have ensured satisfaction of the balance equations, but they developed growth laws separately from the thermodynamics, and failed to satisfy the Clausius–Duhem inequality. Using the continuum thermodynamics of irreversible processes in a mixture context, we show here, for the first time, how satisfaction of the Clausius–Duhem inequality motivates and structures the growth law. [Copyright &y& Elsevier]

During embryonic development, the telecephalon undergoes extensive growth and cleaves into right and left cerebral hemispheres. Although molecular signals have been implicated in this process and linked to congenital abnormalities, few studies have examined the role of mechanical forces. In this study, we quantified morphology, cell proliferation and tissue growth in the forebrain of chicken embryos during Hamburger-Hamilton stages 17-21. By altering embryonic cerebrospinal fluid pressure during development, we found that neuroepithelial growth depends on not only chemical morphogen gradients but also mechanical feedback. Using these data, as well as published information on morphogen activity, we developed a chemomechanical growth law to mathematically describe growth of the neuroepithelium. Finally, we constructed a three-dimensional computational model based on these laws, with all parameters based on experimental data. The resulting model predicts forebrain shapes consistent with observations in normal embryos, as well as observations under chemical or mechanical perturbation. These results suggest that molecular and mechanical signals play important roles in early forebrain morphogenesis and may contribute to the development of congenital malformations., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2019. Published by The Company of Biologists Ltd.)