Dominant Coefficients Research Articles

Electrogastrography in Adult Gastroparesis: A Systematic Review and Meta-Analysis

BackgroundGastroparesis is a delay in gastric emptying without mechanical obstruction, lacking a clear pathophysiological mechanism, but with multiple histological abnormalities including loss of interstitial cells of Cajal, which may alter slow waves. We can assess slow waves with electrogastrography.ObjectivesTo determine the prevalence and range of abnormalities in gastric slow waves in adults with gastroparesis using electrogastrography.MethodsWe systematically searched Medline, Embase, LILACS, Web of Science, and Cochrane Register of Controlled Trials. We included studies with patients older than 18 years with gastroparesis, assessed using electrogastrography. We evaluated the percentage of duration of the recording in which the dominant power was in normogastria, tachygastria, and bradygastria; dominant frequency; power ratio; change in post-stimulus dominant power; and dominant frequency instability coefficient. Methodological quality was assessed using the Joanna Briggs Institute tool. Data were synthesized using narrative summary and meta-analysis.ResultsA total of 3730 articles were reviewed, including 31 articles with 1545 patients and 340 controls. Compared to controls, gastroparetics patients had less normogastria (fasting: 50.3% versus 65.8%) (post-stimulus: 54.3% versus 66.5%), more bradygastria (fasting: 37.7% versus 13%) (post-stimulus: 31.9% versus 16.3%), and more tachygastria (fasting: 16.1% versus 4.6%) (post-stimulus: 18.3% versus 5.2%). Gastroparetics had less change in post-stimulus dominant power (1.45 dB versus 5.03 dB) and less power ratio (1.4 versus 5.26).ConclusionsGastroparetic patients present abnormalities in the frequency and changes in the post-stimulus power of slow waves, possibly secondary to a reduced number of interstitial cells of Cajal, as described in these patients.

Growth Estimates of Solutions of Linear Differential Equations with Dominant Coefficient of Lower (α, β, γ)-order

Growth Estimates of Solutions of Linear Differential Equations with Dominant Coefficient of Lower (α, β, γ)-order

Inégalités de type Remez dans le plan

We obtain a sharp upper bound on the modulus of a complex polynomial ppzq at any boundary point of a domain G € C bounded, the area of the subset of G, where |ppzq| ¤ 1, is known. Remez’s inequality makes it possible to give an increase on the supremum norms of certain polynomials, the increase being reached by the Chebyshev polynomials. Similar inequalities have been proven for different classes of functions. an important example is the Nazarov inequality for exponential sums. One of the corollaries of the Remez inequality is the Pòlya inequality which states that the Lebesgue measure of a set of sublevels of a polynomial of degree n is bounded according to its dominant coefficient. Keywords : Remez inequalities, Polynomial, Green’s function.

Constraining models of dominance for nonsynonymous mutations in the human genome.

Dominance is a fundamental parameter in genetics, determining the dynamics of natural selection on deleterious and beneficial mutations, the patterns of genetic variation in natural populations, and the severity of inbreeding depression in a population. Despite this importance, dominance parameters remain poorly known, particularly in humans or other non-model organisms. A key reason for this lack of information about dominance is that it is extremely challenging to disentangle the selection coefficient (s) of a mutation from its dominance coefficient (h). Here, we explore dominance and selection parameters in humans by fitting models to the site frequency spectrum (SFS) for nonsynonymous mutations. When assuming a single dominance coefficient for all nonsynonymous mutations, we find that numerous h values can fit the data, so long as h is greater than ~0.15. Moreover, we also observe that theoretically-predicted models with a negative relationship between h and s can also fit the data well, including models with h = 0.05 for strongly deleterious mutations. Finally, we use our estimated dominance and selection parameters to inform simulations revisiting the question of whether the out-of-Africa bottleneck has led to differences in genetic load between African and non-African human populations. These simulations suggest that the relative burden of genetic load in non-African populations depends on the dominance model assumed, with slight increases for more weakly recessive models and slight decreases shown for more strongly recessive models. Moreover, these results also demonstrate that models of partially recessive nonsynonymous mutations can explain the observed severity of inbreeding depression in humans, bridging the gap between molecular population genetics and direct measures of fitness in humans. Our work represents a comprehensive assessment of dominance and deleterious variation in humans, with implications for parameterizing models of deleterious variation in humans and other mammalian species.

Genetic diversity during selective sweeps in non-recombining populations.

Selective sweeps, resulting from the spread of beneficial, neutral, or deleterious mutations through a population, shape patterns of genetic variation at linked neutral sites. While many theoretical, computational, and statistical advances have been made in understanding the genomic signatures of selective sweeps in recombining populations, substantially less is understood in populations with little/no recombination. We present a mathematical framework based on diffusion theory for obtaining the site frequency spectrum (SFS) at linked neutral sites immediately post and during the fixation of moderately or strongly beneficial mutations. We find that when a single hard sweep occurs, the SFS decays as 1/ x for low derived allele frequencies ( x ), similar to the neutral SFS at equilibrium, whereas at higher derived allele frequencies, it follows a 1/ x 2 power law. These power laws are universal in the sense that they are independent of the dominance and inbreeding coefficient, and also characterize the SFS during the sweep. Additionally, we find that the derived allele frequency where the SFS shifts from the 1/ x to 1/ x 2 law, is inversely proportional to the selection strength: thus under strong selection, the SFS follows the 1/ x 2 dependence for most allele frequencies, resembling a rapidly expanding neutral population. When clonal interference is pervasive, the SFS immediately post-fixation becomes U-shaped and is better explained by the equilibrium SFS of selected sites. Our results will be important in developing statistical methods to infer the timing and strength of recent selective sweeps in asexual populations, genomic regions that lack recombination, and clonally propagating tumor populations.

The Dominance of Coinfecting Parasites' Indirect Genetic Effects on Host Traits.

AbstractIndirect genetic effects (IGEs) exist when there is heritable variation in one organism's ability to alter a second organism's traits. For example, parasites have antigens that can induce a host immune response, as well as disparate strategies to evade or suppress host immunity; among-parasite genetic variation in these antigens generates among-host variation in immune traits. Here, we experimentally show that the cestode parasite Schistocephalus solidus exerts an IGE on an immune trait (peritoneal fibrosis) in its threespine stickleback host: stickleback developed strong fibrosis after exposure to some parasite genotypes but not others. A complication arises during coinfection, when two or more parasite genotypes may impose conflicting IGEs on the same host trait. What parasite-controlled trait will the host express? Will the host trait reflect the more immune-stimulatory parasite genotype or the more immune-evasive genotype? These alternatives can be quantified by estimating the dominance coefficient, as if a coinfected host were a heterozygote. We experimentally estimated the dominance of S. solidus IGEs by coinjecting antigens from different parasite genotypes. Contrary to our a priori hypotheses, coinjected antigens induced an overdominant effect, stronger than either parasite's antigens alone. We present a mathematical model showing that the value of this IGE dominance is biologically important, affecting the evolutionary dynamics of parasites in a density- and frequency-dependent manner. The model indicates that overdominance would be detrimental to immigrants when resident prevalence is high. This combination of experimental data and modeling provides an example of a parasite IGE on host traits and the evolutionary significance of IGE dominance.

Revisiting Dominance in Population Genetics.

Dominance refers to the effect of a heterozygous genotype relative to that of the two homozygous genotypes. The degree of dominance of mutations for fitness can have a profound impact on how deleterious and beneficial mutations change in frequency over time as well as on the patterns of linked neutral genetic variation surrounding such selected alleles. Since dominance is such a fundamental concept, it has received immense attention throughout the history of population genetics. Early work from Fisher, Wright, and Haldane focused on understanding the conceptual basis for why dominance exists. More recent work has attempted to test these theories and conceptual models by estimating dominance effects of mutations. However, estimating dominance coefficients has been notoriously challenging and has only been done in a few species in a limited number of studies. In this review, we first describe some of the early theoretical and conceptual models for understanding the mechanisms for the existence of dominance. Second, we discuss several approaches used to estimate dominance coefficients and summarize estimates of dominance coefficients. We note trends that have been observed across species, types of mutations, and functional categories of genes. By comparing estimates of dominance coefficients for different types of genes, we test several hypotheses for the existence of dominance. Lastly, we discuss how dominance influences the dynamics of beneficial and deleterious mutations in populations and how the degree of dominance of deleterious mutations influences the impact of inbreeding on fitness.

Relationship between the nature of the symptomatology in schizophrenia and the type of manual dominance

Background and objectives: Despite years of research, there is still no definitive evidence of a link between the clinical manifestations of schizophrenia and atypical asymmetry, and a consistent model of association is lacking. Methods: We examined 70 men diagnosed with schizophrenia according to the criteria of ICD-10 and DSM-IV, using the "Brief Psychiatric Rating Scale" (BPRS). Results: Our analysis revealed several statistically significant correlations between the coefficient of right-hand dominance and symptoms from the BPRS. Conclusion: Positive symptoms are associated with right-handedness and more severe exacerbations of the illness, while affective symptoms in non-right-handed patients may be associated with a more favorable course.

MICROFLORA OF THE UROGENITAL TRACT IN ACUTE PURULENTINFLAMMATORY DISEASES OF THE URINARY SYSTEM AS A PREREQUISITE OF ABDOMINAL SEPSIS

The aim – to ascertain the etiological role of various taxonomic groups of autochthonousand allochthonous microorganisms in the origin of acute purulent- inflammatory diseasesof the urinary system as a prerequisite of abdominal sepsis.Materials and methods. The study covers 145 patients with acute purulent- inflammatorydiseases of the urinary system. When studying the microbiota of the urinary system,standard microbiological methods were used, the number of colony- forming units(CFU) was counted, determining the population level of each species or group of themicroorganisms, the obtained numerical values were converted into a decimal logarithm(lg CFU). The etiopathogenetic value of individual representatives of the microbiotawas assessed by the constancy index, frequency and significance indicators, as well asthe coefficient of quantitative dominance of each type of microorganisms, and otherindicators (Margalef index, Berger- Parker dominance index).Results. Acute purulent- inflammatory diseases of the urinary system are polyetiologicaldiseases caused by microorganisms belonging to different taxonomic groups. The leadingrole belongs to opportunistic Escherichia, to a lesser extent enteropathogenic E.coli,as well as conditionally pathogenic Staphylococci, in addition to that only in a small(13.48 %) number of patients it was not possible to isolate and identify the pathogens.Associations of pathogens were often encountered, which testifies to the need of developingan antimicrobial effect on etiological factors. Conclusions. Acute purulent- inflammatory diseases of the urinary system arecharacterized by polyetiological factors, a variety of pathogens with the dominant roleof Escherichia coli and Staphylococci. The identified pathogens create the potentialfor translocation and formation, under certain conditions, of abdominal sepsis in thiscontingent of patients.

Quantum Reversible Audio Steganalysis Using Quantum Schmidt Decomposition and Quantum Support Vector Machine

Quantum Reversible Audio Steganalysis Using Quantum Schmidt Decomposition and Quantum Support Vector Machine

Towards Transferable Adversarial Attacks with Centralized Perturbation

Adversarial transferability enables black-box attacks on unknown victim deep neural networks (DNNs), rendering attacks viable in real-world scenarios. Current transferable attacks create adversarial perturbation over the entire image, resulting in excessive noise that overfit the source model. Concentrating perturbation to dominant image regions that are model-agnostic is crucial to improving adversarial efficacy. However, limiting perturbation to local regions in the spatial domain proves inadequate in augmenting transferability. To this end, we propose a transferable adversarial attack with fine-grained perturbation optimization in the frequency domain, creating centralized perturbation. We devise a systematic pipeline to dynamically constrain perturbation optimization to dominant frequency coefficients. The constraint is optimized in parallel at each iteration, ensuring the directional alignment of perturbation optimization with model prediction. Our approach allows us to centralize perturbation towards sample-specific important frequency features, which are shared by DNNs, effectively mitigating source model overfitting. Experiments demonstrate that by dynamically centralizing perturbation on dominating frequency coefficients, crafted adversarial examples exhibit stronger transferability, and allowing them to bypass various defenses.

Can Growth Increase of Small Trees after Drought Compensate for Large Trees’ Growth Loss?

Large trees dominate stand-level biomass but their growth suffers more from droughts, while sheltering small trees during droughts. Under a warmer and drier climate, whether the growth decline of large trees could be compensated by prompted small trees’ growth remains unknown. Based on the Standardized Precipitation Evapotranspiration Index (SPEI) series, drought characteristics were determined, and two drought events were selected. We reconstructed historical diameters at breast height (DBH) and the aboveground biomass of Larix gmelinii through tree ring data allometric equations. To clarify the difference in the responses of tree size to drought, we calculated resistance, recovery, and resilience in each diameter class. We used a growth dominance coefficient (GDC) to exhibit the contributions of different-sized individuals to stand growth and demonstrated the growth dynamics of both the individual and stand level. The results proved that large trees were more vulnerable to local droughts, the resilience of larch had a negative relationship with the DBH (p < 0.05), and small trees could recover to even exceed their pre-drought growth level. Most plots had a negative GDC and small trees contributed more to stand growth compared with their size, but their AGB growth was far less than that of large trees, which made it difficult to compensate for stand growth decline. Our results indicate that tree resilience has a negative relationship with their pre-drought sizes, as large trees in the stand fail to regain their growth level before drought. Even with a larger relative contribution and higher resilience, small trees cannot cover deficits in large trees’ growth. Under more frequent droughts, the total aboveground biomass growth of larches would decline.

Effects of Stand Density, Age, and Drought on the Size–Growth Relationship in Larix principis-rupprechtii Forests

The size–growth relationship (SGR) quantifies growth partitioning among different sized trees in a stand and helps to elucidate stand growth dynamics during stand development. SGR strongly correlates with stand density, stand age, and drought severity. This study focused on larch (Larix principis-rupprechtii (Mayr)) forests with different stand ages (17–19 years, 20–29 years, 30–39 years, and 40–46 years) and stand densities (300–1400 trees·ha−1 and 1400–3300 trees·ha−1) as the research subjects. Employing a linear mixed model, we aimed to quantify the effects of stand density, stand age, and drought index on SGR. The results revealed that the Gini coefficient had a significant variation between high-density and low-density larch stands (p < 0.01). Stand age, stand density, and drought index exerted varying degrees of influence on the growth dominance coefficient (GD) and SGR of larch forests. In stands aged less than 39 years, a pronounced growth advantage of large trees over small trees was evident (typically SGR > 1 and GD > 0), indicating a positive growth dominance stage where large trees dominated. Compared to high-density stands, low-density stands exhibited a notably greater positive growth dominance. After 40 years, the growth stage transitioned to a relatively symmetric stage (SGR approximately equal to 1), with a discernible shift towards a reverse growth dominance stage (GD < 0). Compared to stand density and stand age, the drought index had a more influential effect on SGR. As drought severity increased, SGR increased, amplifying the growth advantage of large trees over small ones. The findings underscored the significance of adjusting stand density and optimizing tree size structure to enhance larch resilience against the warming and drying effects.

Dynamic person-position matching decision method based on hesitant fuzzy number information

In view of the fact that people pay more and more attention to the principle of "getting the position according to the person" and "adapting the person to the position" in person-position matching, a dynamic person-position matching decision method based on hesitant fuzzy numbers is proposed. First, the dynamic person-position matching problem with hesitant fuzzy numbers is described. Then, according to hesitant fuzzy evaluation matrices of positions and candidates, expected score matrices of bilateral subjects are calculated. Furthermore, based on the idea of the generalized optimal order method and the dominant correlation and the missing correlation coefficients, satisfaction means of people and positions are calculated. According to satisfaction means, growth satisfactions at each period are obtained, and then the exponential decay formula is used to determine weights of growth satisfactions. Dynamic satisfactions of bilateral subjects are calculated by aggregating initial satisfaction means and growth satisfactions. On this basis, a stable person-position matching model considering dynamic satisfactions is established and then is solved to obtain the optimal stable person-position matching scheme. Finally, the feasibility and effectiveness of the proposed method are verified by an example analysis of person-position matching. Main contributions of this paper are as follows: an effective calculation method for the missing correlation coefficient is presented; a novel effective calculation method for dynamic satisfactions is proposed by introducing the correlation parameter to combine the missing correlation coefficient with the dominant correlation coefficient; an effective stable person-position matching model considering dynamic satisfactions is established.

Excited state absorption induced optical limiting behavior of pure, single, and co-doped copper oxide nanoparticles

Excited state absorption induced optical limiting behavior of pure, single, and co-doped copper oxide nanoparticles

Load Pushing Capacity Analysis of Individual and Multi-Cooperative Mobile Robot through Symbiotic Application

Certain missions require multiple mobile robots working together to accomplish it. There is a need, however, to determine the optimal configuration of modular mobile robots doing cooperative tasks to ensure high utilization and efficiency rate of the individual robot. This study proposed the use of a biosystem-inspired approach in assessing the influence of multiple robots on each other in performing a cooperative pushing task. The kinematics of pushing interaction at a single contact point was first discussed in the study to provide a solid foundation of the mission to be analyzed. Various dimensions in an experimental setup were also covered to better understand how these contribute to planar pushing. Through the resulting symbiotic coefficient, the study was able to determine the optimal configuration among the two, four, and six wheeled mobile robots pushing an object with various loads. While the dominant coefficient for symbiotic relationship was classified as beneficial and only one was neutral, the decline in coefficient values of the 3rd configuration (six wheeled) with respect to the 2nd configuration (4 wheeled) implies possible negative coefficient in the next configuration (8 wheeled). The maximum level of distance at which an object can be pushed was also obtained. This was called the state of plateau wherein adding another module is no longer suggested as it will not improve the pushing capacity any further. Knowing these key points significantly helps in ensuring cost and work efficiency of a given configuration in performing different missions.

Multi-Objective Optimization of Injection Molding Process Parameters for Moderately Thick Plane Lens Based on PSO-BPNN, OMOPSO, and TOPSIS

Injection molding (IM) is an ideal technique for the low-cost mass production of moderately thick plane lenses (MTPLs). However, the optical performance of injection molded MTPL is seriously degraded by the warpage and sink marks induced during the molding process with complex historical thermal field changes. Thus, it is essential that the processing parameters utilized in the molding process are properly assigned. And the challenges are further compounded when considering the MTPL molding energy consumption. This paper presents a set of procedures for the optimization of injection molding process parameters, with warpage, sink marks reflecting the optical performance, and clamping force reflecting the molding energy consumption as the optimization objectives. First, the orthogonal experiment was carried out with the Taguchi method, and the S/N response shows that these three objectives cannot reach the optimal values simultaneously. Second, considering the experimental data scale, the back propagation neural network updated by the particle swarm optimization method (PSO-BPNN) was applied to establish the complex nonlinear mapping relationship between the process parameters and these three trade-off objectives respectively. Then, the Pareto optimal frontier of the multi-objective optimization problem was attained by multi-objective particle swarm optimization using a mutation operator and dominance coefficient algorithm (OMOPSO). And the competitive relationship between these objectives was further confirmed by the corresponding pairwise Pareto frontiers. Additionally, the TOPSIS method with equal weights was employed to achieve the best optimal solution from the Pareto optimal frontier. The simulation results yielded that the maximum values of warpage, sink marks, and clamping force could be reduced by 7.44%, 40.56%, and 5.56%, respectively, after optimization. Finally, MTPL products were successfully fabricated.

MICROBIOLOGICAL CHARACTERISTICS OF THE LAPAROTOMIC WOUND, WHEN COMPLETE EVENTRATION BEGINNING, IN THE ONCOLOGICAL PROCESS

The aim of the study –to study the peculiarities of the qualitative and quantitative compositionof the microflora of the wound exudate of the laparotomy wound, complicated by the eventration,depending on its degree, in patients with malignant neoplasms of the abdominal cavity.Materials and methods.28 patients with malignant neoplasms of abdominal organs who hadpostoperative eventration were studied. The main group consisted of 12 patients who hada complete eventration (grade II-IV). The comparison group was formed by 16 patients whohad subcutaneous eventration (I degree). The collection of biological material was carriedout during the 8th day of the early postoperative period, by bacteriological examinationof the wound exudate, during dressings. Species composition of microorganisms, theirpopulation level, the coefficient of constancy, the frequency of species detection, thecoefficient of significance, the coefficient of quantitative dominance was studied.Results. When eventration II-IV degrees occurs, against a background of the oncologicalprocess, a probable predominance of the number of strains of E. coli, S. aureus and m/o ofthe genus Proteus is noted, and the number of strains of E. coli is likely to prevail during allperiods of observation. During the development of II-IV degrees of eventration, due to theoncological process, in the exudate of the laparotomy wound, there is a probable predominanceof the population level of E. coli, S. aureus and m/o of the genus Proteus. The dominantmicroorganism, according to the determined coefficient of quantitative dominance, at alldegrees of eventration, throughout the entire period of the study, is E. coli, and Enterococcusfaecalis is in the second place. At the same time, at all degrees of eventration, high numbers ofthe coefficient of quantitative dominance in S. aureus are noted on the 6-8th day of the study. 
 Conclusions. With the development of postoperative eventration of II-IV degrees, inpatients with malignant neoplasms of the abdominal cavity, a probable increase in thenumber of strains sown and the population level of microorganisms in the laparotomywound exudate with E. coli, S. aureus and microorganisms of the genus Proteus is noted.In patients with malignant neoplasms of the abdominal cavity, with the occurrence ofII-IV degrees of postoperative eventuration, the dominant microorganisms of the woundexudate are E. coli and Enterococcus faecalis and microorganisms of the genus Proteus.

Temporal changes in size inequality and stand growth partitioning between tree sizes under various thinning intensities in subtropical Cunninghamia lanceolata plantations

Temporal changes in size inequality and stand growth partitioning between tree sizes under various thinning intensities in subtropical Cunninghamia lanceolata plantations

Driving mechanisms of productivity stability vary with selective harvesting intensities in a mixed broad-leaved Korean pine forest

Key messageWe found that the stabilizing mechanisms for forest productivity varied across harvesting intensities in a mixed broad-leaved Korean pine forest. Effects of overyielding at high species richness and species asynchrony occurred only in unharvested and lightly harvested plots, whereas asymmetries between individuals of different size contributed significantly to stabilizing productivity when harvestings became intensive.ContextUnderstanding the driving factors of forest ecosystem stability has become increasingly crucial in forest management. However, it remains unclear whether and how the stabilizing mechanisms of forest productivity might be influenced by management practices.AimsWe related the temporal stability of aboveground biomass productivity to harvesting history. We further tested how three key driving mechanisms of stability might be modulated by selective harvesting intensities.MethodsBased on a 10-year monitoring (five repeated tree inventories) of a mixed broad-leaved Korean pine forest in Northeastern China recovering from selective harvesting, we examined the relative importance of two diversity-dependent mechanisms (overyielding and species asynchrony) and one size-dependent mechanism (asymmetric growth) for productivity stability across a wide range of intensities (0–73.4% basal area removed).ResultsWe found that selective harvesting significantly lowered the productivity stability, species asynchrony, and growth dominance coefficient. Growth dominance coefficient had an overall stronger effect on stability than species richness and asynchrony. Moreover, the strengths of stabilizing mechanisms varied across harvesting intensities: effects of overyielding at high species richness and species asynchrony were detected only in unharvested and lightly harvested plots, whereas the explanatory power of growth dominance coefficient outweighed the diversity-related variables when harvesting became intensive.ConclusionsWe emphasized the importance to consider both diversity- and size-related explanatory variables as potential mechanisms for the temporal stability of forest productivity. In fact, how growth is partitioned among trees of different species as well as sizes may co-determine the response of forest stability to disturbances.