Growth Phenomena Research Articles

Serum Adipocytokines Profile in Children Born Small and Appropriate for Gestational Age—A Comparative Study

Adipose tissue is not only a storage place for fat, but also an endocrine organ, secreting bioactive molecules which influence body metabolism. Such molecules are known as adipocytokines. In the past years the coincidence between adipocytokines and fetal growth restriction disorders was found. The aim of the study was to estimate serum levels of adiponectin, leptin and resistin in children born small for gestational age, compared to children born at an appropriate size for gestational age. The study consisted of 35 children aged seven to nine years, born SGA (small for gestational age) on term and 25 healthy children (14 girls, 11 boys), born with proper birthweight (AGA-appropriate for gestational age)-control group. Adiponectin and leptin levels were significantly higher in the SGA group compared to the AGA group (p = 0.023, p = 0.018 respectively). The resistin values were comparable in both groups of patients. There was a positive correlation between serum leptin concentration and current body weight in SGA group (r = 0.28; p = 0.108). In turn, adiponectin levels in this group of patients negatively correlated with actual body weight (r = -0.51; p = 0.002). The negative correlation between body mass index and plasma adiponectin levels was found only in children born SGA. SGA children had significantly higher values of diastolic blood pressure. There was negative correlation between serum adiponectin level and systolic blood pressure in SGA children. In the SGA group the phenomenon of catch-up growth was observed in 32 children. Children born SGA have abnormal adipose tissue biomarkers profiles.

Experimental investigation of crack opening loads in an aircraft load spectrum

The concept of plasticity-induced fatigue crack closure is indispensable in explaining many fatigue crack growth phenomena; and it is now widely applied in advanced fatigue life evaluation procedures. This concept has been extensively investigated experimentally over the past sixty years using different methods. However, most of these investigations are related to constant amplitude loading or simple load cases such as single or multiple overloads or block loading. In contrast, there are currently no experimental studies investigating crack closure under variable amplitude loading or load spectra, which are more realistic scenarios. This can be attributed to the many difficulties associated with the evaluation of crack opening loads for large numbers of fatigue cycles, including sensor sensitivity, signal noise, data limits, etc. Recently, the authors proposed an advanced piezoelectric sensor for cycle-by-cycle crack opening load measurements, which addresses the above limitations. In this work, the piezoelectric sensor is utilised to investigate crack closure under a typical transport aircraft load spectrum. In particular, it is demonstrated that crack opening load levels can change significantly from cycle-to-cycle, and these levels are typically larger than for constant amplitude loading at the same R-ratio. The relative density plot of crack opening load levels reveals three distinct regions, which can be associated with certain load sequences. The outcomes of this research are important for the development and validation of spectrum compression algorithms as well as advanced fatigue life evaluation procedures.

Candidate genes potentially involved in molting and body size reduction in the male of the horned gall aphid, Schlechtendalia chinensis.

In general, insects grow (increase in body size) through molting. To the opposite, the body size of the males of the horned gall aphid, Schlechtendalia chinensis, gets smaller after molting and as they age. To understand the molecular bases of this rare phenomenon, transcriptomes were generated from 1-5days old male and the data were analyzed via a weighted gene co-expression network analysis (WGCNA). A total of 15 partitioned modules with different topological overlaps were obtained, and four modules were identified as highly significant for male body length (p < 0.05). Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis suggested that a portion of genes in the four modules are likely involved in autophagy and apoptosis. In addition, a total of 40 hub genes were obtained in the four modules, and among them eight genes were highly expressed in males compared to individuals of other generations of S. chinensis. These eight genes were associated with autophagy and apoptosis. Our results reveal the unique negative growth phenomenon in male S. chinensis after molting, and also suggest that the male S. chinensis with no ability to feed probably decompose their own substances via autophagy and apoptosis to provide energy for life activities such as germ cell development.

Dynamic Mechanism of Dendrite Formation in Zhoukoudian, China

Dendrite, a typical geological pattern, is developed along the bedding plane in limestone and dolomite strata in Jinzigou area, Zhoukoudian, Beijing, China, with a self-similar dendritic morphology. In order to reveal the dynamic mechanism of its formation, the diffusion-limited aggregation method, a model of fractal growth, was selected to simulate the microscopic dynamic mechanism of its formation. Take an L × L square lattice, with L = 200 lattices, 20,000 particles, and L = 250 lattices, 30,000 particles, for simulation. Obtain the simulation results of the dendritic pattern and the intermediate results with 8057 and 10,827 random particles released in the simulation process with 20,000 particles. The results show that the pattern is a typical fractal pattern formed in the process of fractal growth, with a fractal dimension of about 1.6. Its morphology is characterized by fractal geometry, and the dynamic mechanism of its formation is the fractal growth phenomenon generated by self-organizing criticality. The growth process is a nonlinear and non-equilibrium evolutionary process, which is dynamic and far from equilibrium. It is consistent with the fractal dimension of Zhoukoudian dendrite (1.52–1.78). Diffusion-limited aggregation (DLA) is a typical growth process in fractal growth. It leads to the growth of randomly branching structures that closely resemble various important systems in the earth sciences, providing a theoretical basis for revealing the nature of complex geological processes.

Fractal patterns from dried droplets. A method to test nanoscale features of nanoparticles and vesicles.

There has been considerable research into fractal growth phenomena attempting to understand the physical and chemical driving forces behind this phenomenon. In this work, we analyzed the size ranging from 30 to 1000nm. The electrostatic charge, zwitterionic and negative. And, the composition, Soft; DPPC, DMPC, and hard; CoFe2O4, Co3O4, PE, SiO. Then, we compared the droplet pattern images with two algorithms: a well-established method, the fractal dimension, and a novel algorithm. Our results will provide a base for further understanding, quantification, and applicability of droplets.

Three-dimensional growth simulation of swellable soft materials based on CS-FEM

In this paper, a three-dimensional numerical framework for modeling growth of swellable soft materials at large deformation is established based on the cell-based smooth finite element method, and the multiplicative decomposition scheme of deformation gradient is given. The second P-K stress and Green's strain tensor are selected as work conjugate pairs, and the corresponding mathematical expressions of stiffness matrix and geometric stiffness matrix are derived. The numerical method is implemented based on Matlab platform, and the isotropic and anisotropic growth behaviors of swellable soft materials are simulated respectively. The results show that anisotropic growth will inhibit the deformation of expandable soft materials compared with isotropic growth. The simulation results are compared with the calculation results in the existing literature. The comparison results show that the characteristics and the morphological mode are in good agreement, which proves the effectiveness of the numerical framework in simulating the growth behavior of expandable soft materials at large deformation, and is able to reveal the mechanical mechanism of the plant growth phenomenon in nature.

Fracture of brittle material with two 3D parallel internal cracks under thermal stress: Experimental and numerical analysis

Many defects such as cracks are often present inside brittle solids, and most of the cracks do not appear in a single form. The fracture and failure of brittle solids are basically caused by the interaction and expansion of multiple cracks. Most of the traditional studies on this topic have focused on surface or penetration crack interaction under tensile and compressive loads, while there have been very few studies on the expansion characteristics and interaction of parallel internal cracks under temperature loading. This study applies the 3D internal laser-engraved crack (3D-ILC) method to fabricate parallel internal cracks inside the 3D cube. Physical tests and numerical simulations of parallel internal cracks of different sizes and single crack propagation under temperature fields are carried out, and the propagation characteristics of internal cracks and the interaction between parallel internal cracks of unequal size under temperature loading are investigated. The study results show that the big crack will inhibit and shield the expansion of the small crack. In addition, there are typical “anti-binary tree” mode III features on both sides of the parallel large crack and single large and small crack propagation surface, which are classified as mixed I-II-III crack, while the parallel small cracks are mode I-II. Compared with the quasi-static crack growth criterion, the simulation results of the subcritical crack growth criterion are more in line with the physical test results, and there is a subcritical growth phenomenon in the parallel crack propagation under the temperature load. The results provide experimental and theoretical references for the study of 3D bi-parallel cracks interaction of different sizes and the fracture of mode I-II-III crack under the temperature field.

Effect of TiC additions on the microstructure, mechanical and tribological properties of NbC-CoCrFeNiMn high entropy alloys cermets

NbC-xTiC-15CoCrFeNiMn (x = 0, 5, 10, 15) cermets were prepared by powder metallurgy, and the effects of the addition of second-phase carbide TiC on microstructure, mechanical properties and wear resistance of the cermets were systematically investigated. The results showed that the grain growth phenomenon occurred more obviously in the cermets without TiC addition, while the addition of TiC led to effective suppression of grain growth. Meanwhile, TiC additions resulted in significant increases in hardness under fine grain strengthening effect and solid solution strengthening effect. The NbC-10TiC-15CoCrFeNiMn cermet exhibited the highest transverse strength. With adding 15 vol% TiC, the cermets exhibited the highest relative density of 98.0% and the highest hardness of 1471.5 kg/mm2. Furthermore, the addition of TiC improved wear resistance of the cermets. The adhesive wear was gradually reduced with increasing TiC contents, and NbC-15TiC-15CoCrFeNiMn cermets exhibited the smallest wear depth.

The Possibilities OF Transcultural Positive Psychotherapy in Supporting the Development of Post-Traumatic Growth (PTG)

Technological and sociocultural changes taking place over the last decades have, on the one hand, increased the probability of experiencing trauma during human life, and on the other, contributed to the development of neuroscience, and thus to expanding knowledge about the symptoms, diagnosis and treatment of trauma-related disorders. Attention began to be drawn to the fact that experiencing trauma can not only lead to negative consequences, but also can be a source of positive changes in an individual. This phenomenon is defined as post-traumatic growth, which may manifest itself in one (or more) of the four areas of human life. As a result of a traumatic experience, some people may increase the sense of self-confidence and trust in their own abilities, may become convinced of their personal strength and effectiveness, may improve relationships with other people, or begin to appreciate life and have hope for the future’s changes. Post-traumatic growth is more than an adaptive strategy to a post-traumatic situation. Growth means development, i.e. achieving a better level of functioning of the individual than before experiencing the trauma. The development of an individual is part of the Transcultural Positive Psychotherapy (PPT after Peseschkian) objective, which focuses on developing human potential by changing the perspective, enhancing hope, differentiating capabilities, discovering coping skills and finding a sense of meaning even in the most extreme life events. This article aims to show the usefulness of Positive Psychotherapy after Peseschkian in supporting post-traumatic growth. Starting with the characteristics of the post-traumatic growth phenomenon, will discuss the factors correlating with the emergence of positive post-traumatic changes and will finally show how the main principles and tools of this method can be helpful in reinforcing post-traumatic growth.

Influence of the multilayer dielectric mirror design on the laser damage growth in the sub-picosecond regime.

The peak power of high-power laser facilities is limited by the laser-induced damage to the final optical components. Also, when a damage site is generated, the damage growth phenomenon limits the lifetime of the component. Many studies have been performed to improve the laser-induced damage threshold of these components. The question now arises as to whether improvement of the initiation threshold leads to a reduction of the damage growth phenomenon. To address this question, we performed damage growth experiments on three different multilayer dielectric mirror designs exhibiting different damage thresholds. We used classical quarter-wave designs and optimized designs. The experiments were carried out with a spatial top-hat beam, spectrally centered at 1053nm with a pulse duration of 0.8ps in s- and p-polarization. The results showed the impact of design on the improvement of the damage growth thresholds and a reduction of the damage growth rates. A numerical model was used to simulate damage growth sequences. The results reveal similar trends to those observed experimentally. On the basis of these three cases, we have shown that improvement of the initiation threshold through a modification of the mirror design can lead to the reduction of the damage growth phenomenon.

Atomistic insights into sluggish crystal growth in an undercooled CoNiCrFe multi-principal element alloy

Crystal growth in undercooled CoNi, CoNiCr and CoNiCrFe equi-atomic alloys was investigated by molecular-dynamics simulation to show atomistic insights into sluggish crystal growth in the undercooled CoNiCrFe multi-principal element alloy (MPEA). The simulation results showed that the growth velocity decreases gradually and the crystallization kinetics became sluggish as the increasing number of principal elements, being qualitatively consistent with the experiments. Independent of the number of principal elements, the activation controlled crystal growth mechanism always played a dominative role. The sluggish crystal growth phenomenon in the undercooled CoNiCrFe MPEA was found to be due to the increased growth activation energy and the decreased ultimate growth velocity. By converting the atomic displacement arose at the process of crystallization into timescales, the contribution of each element to the growth activation energy was quantified for the first time. Consequently, the important role of the Cr element in increasing the growth activation energy was revealed, being qualitatively consistent with experimental findings that the adding amount of Cr element played a dominate role in sluggish crystal growth. An implementation of the time dependent Ginzburg-Landau theory for solidification kinetics indicated that the weakened density relaxation capacity of the melt led to a significant decrease of the ultimate growth velocity as the increasing number of principal elements.

Super-Exponential Growth in Models of a Binary String World.

The Theory of the Adjacent Possible (TAP) equation has been proposed as an appropriate description of super-exponential growth phenomena, where a phase of slow growth is followed by a rapid increase, leading to a "hockey stick" curve. This equation, initially conceived to describe the growth in time of the number of new types of artifacts, has also been applied to several natural phenomena. A possible drawback is that it may overestimate the number of new artifact types, since it does not take into account the fact that interactions, among existing types, may produce types which have already been previously discovered. We introduce here a Binary String World (BSW) where new string types can be generated by interactions among (at most two) already existing types. We introduce a continuous limit of the TAP equation for the BSW; we solve it analytically and show that it leads to divergence in finite time. We also introduce a criterion to distinguish this type of behavior from the familiar exponential growth, which diverges only as t → ∝. In the BSW, it is possible to directly model the generation of new types, and to check whether the newborns are actually novel types, thus discarding the rediscoveries of already existing types. We show that the type of growth is still TAP-like, rather than exponential, although of course in simulations one never can observes true divergence. We also show that this property is robust with respect to some changes in the model, as long as it deals with types (and not with individuals).

Elastic response analysis of cylindrical vessels subjected to internal explosion

Strain growth and buckling are typical phenomena of pressure vessels under internal explosion load. To study the mechanism of the strain growth and buckling phenomena, the numerical simulations are performed by LS-DYNA to study the elastic response of the cylindrical vessels under internal explosion. The results show that for the cylindrical vessel with a free boundary, the response of the vessel is a breathing-like mode under the small explosive loading. When the explosive loading becomes larger, the response of the vessel is a breathing-like mode in the early stage and a coupling of breathing-like mode and buckling response in the late stage. The phenomenon of buckling is caused by large bending deformation. According to the response characteristics of the vessel at different stages, an improvement to the traditional idea of strain growth phenomenon was proposed, and the strain growth phenomenon is split into two stages: the first stage is defined as the strain fluctuation stage of the vessel in the breathing-like mode; the second stage is defined as the strain growth stage of the vessel evolving from the breathing-like mode to the buckling mode. The results show that the buckling phenomenon will increase the displacement of the container, but it does not necessarily lead to strain growth phenomenon and sometimes it may even weak the strain. There is an edge effect is found during the study, which must have to lead an increase in the degree of the response of the vessel.

AE Characteristic and Mechanical Behaviors of Red Sandstone with Two Prefabricated Close-Collinear-Equal Length Cracks under Compression.

Preexisting cracks are of great significance for the stability of rocks, they can influence the growth and propagation pattern of cracks. For revealing the failure characteristics of rocks with prefabricated cracks, the mechanical behaviors of red sandstone with two close-collinear-equal length cracks were studied by acoustic emission (AE) monitoring experiment. The results indicated that the stress of red sandstone specimens showed an obvious stepwise growth phenomenon, and AE ring counts can better characterize the growth of microcracks of rocks. Moreover, AE events were mainly distributed near the prefabricated cracks of rocks. Then, a novel modified Kachanov method for analyzing collinear-close cracks was proposed. The influences of crack length and crack spacing on the interaction force of cracks were discussed. Then, it can be found that this modified method had a good applicability for two close-collinear-equal length cracks of rocks under compression.

Fast grain growth phenomenon in high-entropy ceramics: A case study in rare-earth hexaaluminates

It is generally reported that the grain growth in high-entropy ceramics at high temperatures is relatively slower than that in the corresponding single-component ceramics owing to the so-called sluggish diffusion effect. In this study, we report a fast grain growth phenomenon in the high-entropy ceramics (La_0.2Nd_0.2Sm_0.2Eu_0.2Gd_0.2)MgAl₁₁O₁₉ (HEMA) prepared by a conventional solid-state reaction method. The results demonstrate that the grain sizes of the as-sintered HEMA ceramics are larger than those of the corresponding five single-component ceramics prepared by the same pressureless sintering process, and the grain growth rate of HEMA ceramics is obviously higher than those of the five single-component ceramics during the subsequent heat treatment. Such fast grain growth phenomenon indicates that the sluggish diffusion effect cannot dominate the grain growth behavior of the current high-entropy ceramics. The X-ray photoelectron spectroscopy (XPS) analysis reveals that there are more oxygen vacancies (O_V) in the high-entropy ceramics than those in the single-component ceramics owing to the variable valance states of Eu ion. The high-temperature electrical conductivities of the HEMA ceramics support this analysis. It is considered that the high concentration of O_V and its high mobility in HEMA ceramics contribute to the accelerated migration and diffusion of cations and consequently increase the grain growth rate. Based on this study, it is believed that multiple intrinsic factors for the high-entropy ceramic system will simultaneously determine the grain growth behavior at high temperatures.

Clinical Case Reports 1976 - 79

In this paper five case reports were presented and include growth of hypoplastic right ventricle following pulmonary valvotomy, intracavitary electrocardiography in the diagnosis of Ebstein’s anomaly of the left atrioventricular valve in congenital corrected transposition of the great arteries, growth phenomenon as a cause of kinking of the right pulmonary artery in Waterston anastomosis, the usefulness of pulmonary vein wedge angiography in the visualization of an obstructed pulmonary artery, false aneurysm of the right pulmonary artery as a new complication of the Waterston anastomosis. For each case report, clinical, chest x-ray, electrocardiogram, angiogram, and other pertinent findings were presented. This was followed by discussion of etiology, diagnosis, and treatment options, as appropriate.

Instabilities in a growing system of active particles: scalar and vectorial systems.

The physics of micron-scale biological colonies usually benefits from different out-of-equilibrium sources. In bacterial colonies and cellular tissues, the growth process is among the important active sources that determine the dynamics. In this article, we study the generic dynamical instabilities associated with the growth phenomena that may arise in both scalar and vectorial systems. In vectorial systems, where the rotational degrees of particles play a role, a phenomenological growth-mediated torque can affect the rotational dynamics of individual particles. We show that such a growth-mediated torque can result in active traveling waves in the bulk of a growing system. In addition to the bulk properties, we analyze the instabilities in the shape of growing interfaces in both scalar and vectorial systems.

Mechanical modeling of growth applied to Saccharomyces cerevisiae yeast cells

A theoretical and numerical model is developed to describe the growth of Saccharomyces cerevisiae yeasts. This kind of cells is considered here as an axisymmetrical and deformable structure, the inner surface of which is continuously acted upon by a high turgor pressure. Due to the small ratio between the cellwall thickness and the cell radius, a structural shell approach is used. Moreover, the finite strain range is assumed because of the soft nature of these cells. The adopted kinematics is herein based on the multiplicative decomposition of the deformation gradient into an elastic part Fe and an irreversible part related to the growth Fg, i.e. F = FeFg. The reversible response is described using an hyperelastic model of the Ogden type. In accordance with continuum thermodynamics requirements, a criterion is introduced to control the evolution of the growth phenomenon. In this latter two parameters are involved: a growth stress-like threshold, and a growth characteristic time. Embedded within the finite element framework, an illustrative example shows the growth phenomenon of spherical cells going from yeast bud emergence to the step just before cell division. A parametric study highlights the influence of the above mentioned parameters on the cell responses.

Study on the trace moisture influence on the adhesion phenomenon in Cd-based crystal growth

The chemical reactions between trace moisture and raw Cd materials and their effect on the adhesion phenomenon during Cd-based crystal growth were investigated.

Experience of biological therapy in severe forms of chronic rhinosinusitis with nasal polyps in the conditions of regional healthcare

To analyze our own experience, clinical and organizational features of the application of the method of biological therapy in patients with severe forms of recurrent CRSwNP. 25 patients with severe and moderate forms of CRSwNP were examined, who, in a round-the-clock hospital (model CSG 36.018) was treated with Dupilumab, in the form of subcutaneous injections of 300 mg/2 ml 1 every two weeks. The diagnosis was confirmed on the basis of anamnestic data, SNOT-22 quality of life questionnaires, visual endoscopic examination, evaluation of CT data (Lund-Mackay scale), laboratory data. The effectiveness of treatment was monitored after 16 weeks, based on endoscopic examination data, evaluation of CT and SNOT-22 data. In 3 observations, a study of pathomorphological material for tissue eosinophilia was performed. The duration of the course of treatment ranged from 10 to 56 weeks. The most striking clinical effect was observed for signs such as sense of smell and nasal breathing (in some cases-after the first injection). The degree of regression of polyps according to CT and endoscopic examination was more prolonged in time, the same dynamics was observed in the level of total IgE. In a number of patients, the phenomenon of eosinophilia growth was observed against the background of treatment (with regression of clinical symptoms). Pathomorphological examination confirmed a high level of tissue eosinophilia as one of the fundamental signs of Th2 inflammation. One patient with concomitant chronic tubar dysfunction had an improvement in hearing. All patients with AD noted a subjective improvement in disease control (a decrease in the frequency and severity of choking attacks). The cancellation (break in treatment) of treatment was accompanied by a gradual return of symptoms in all patients at various times. Patients who have not achieved an acceptable level of control of CRSwNP,that meets the criteria of Th2 inflammation can be considered as candidates for the use of targeted biological therapy. With strict compliance with the selection criteria, there is a good clinical effect, primarily in relation to nasal symptoms (sense of smell and nasal breathing) and improved control of asthma symptoms.