Distribution Analysis Method Research Articles

The localization and improvement of the Functional Status Scale and the reliability and validity in very low birth weight infants.

To develop a Chinese version of Functional Status Scale (FSS) and to test its reliability and validity in very low birth weight infants (VLBWIs). The FSS was translated into Chinese and the content was modified in accordance with relevant guidelines and specifications. The Chinese version of FSS was applied to evaluate VLBWIs admitted from January 2018 to June 2020 at 7th day after birth and 34 weeks of postmenstrual age, respectively. The scores were analyzed by descriptive statistics (coefficient of variation method, critical ratio method and answer distribution analysis method), and the reliability and the validity were analyzed. The internal consistency reliability was analyzed using Cronbach's α coefficient, the inter rater reliability was analyzed using Spearman correlation coefficient. The content validity was analyzed using correlation coefficient method and expert scoring method; the structural validity was analyzed using exploratory and confirmatory factor analysis method; the known group validity was analyzed using area under the curve (AUC) value and Pearson correlation coefficient. The preliminary response of the initial and re-evaluation scales was calculated. After screening by inclusion and exclusion criteria, 548 and 523 VLBWIs were included for initial evaluation and re-evaluation, respectively. Descriptive statistics showed that the mean was close to the median, the maximum and minimum values were close to or equal to the values at both ends, and the coefficient of variation was >0.15. The critical ratio method showed that the | t| value of all items in the initial evaluation and re-evaluation was >3 ( P<0.01). The answer distribution analysis method showed that the answer selection rate of different levels of each item was <80%. Internal consistency test showed that the general Cronbach's α was 0.803 and the re-evaluation Cronbach's α was 0.708, with a good internal consistency. According to the inter-rater reliability, the Spearman correlation coefficient was 0.968 in the initial evaluation and 0.989 in the re-evaluation ( P<0.01). The correlation coefficient of the items in the scale by the correlation coefficient method was more than 0.4. The item-level content validity index (I-CVI) was greater than 0.78, universal agreement of scale of content validity index was 0.83, the average of scale of content validity index was 0.97 and the Kappa was greater than 0.74. Exploratory factor analysis showed that the initial Kaiser-Meyer-Olkin (KMO) value was 0.846, the re-evaluated KMO value was 0.843 ( P<0.01). There was one factor with extracted eigenvalue>1, which could explain 54.221% and 53.403% of the total variation respectively, suggesting that there was a common factor in the initial evaluation and re-evaluation scales, which was consistent with the original scale design. Confirmatory factor analysis showed that the items in the initial and re-evaluation were significant ( P<0.01), and the value of standard load coefficient was greater than 0.5. The known group validity showed that FSS had a good predictive and discriminative ability for short-term outcomes. The items of mental status, motor function, sensory and communication in the re-evaluation scale had a good correlation with gross motor and fine motor energy areas in Gesell developmental schedule. The Pearson correlation coefficient between initial evaluation and re-evaluation was 0.609 ( P<0.01). The Chinese version FSS scale has good reliability and validity, the included items are simple and easy to be applied in clinical practice.

Средства установления когезивных связей в англоязычном теологическом тексте

The article is devoted to identifying the key means of establishing coherence relations in the English-language theological text. The topicality of the study is conditioned by the fact that the coherence of the text is one of the central objects of consideration within the framework of text linguistics. Currently, not all the mechanisms for creating coherence in scientific texts on theological subjects have been identified, which also requires certain attention of linguists. The research material includes a corpus of 560 contexts selected by the continuous selection method from monographs and other printed and electronic scientific works of a theological nature in the modern English language. The main research methods are the method of continuous selection, methods of discursive analysis, the method of distributive analysis, as well as methods of quantitative calculation. In the course of the work, the analysis of English-language discursive fragments on theological topics has been carried out in order to establish coherence relations in the text. Within the framework of the work, it has been revealed that among the key ways of creating coherence in an English-language theological text, one can name: pronominal substitution as a kind of indexical coherence, anaphoric or epiphoric repetition, hypo-hypernymic general-private relations between individual lexical units in successive sentences, belonging of thematic lexis to a single lexico-semantic (including terminological) field, the use of synonyms / antonyms, coordinate and subordinate conjunction connections. The fact is emphasized that in most cases, several ways of creating coherence can be used simultaneously in the English-language theological text, in particular, the use of subordinate conjunction connections and lexical repetitions or synonymic nominations.

METHODOLOGICAL FOUNDATIONS OF LINGUISTIC RESEARCH BY A. BAITURSYNOV

The article discusses the directions, scientific and methodological foundations of linguistic research of the first linguist in Kazakh linguistics A. Baitursynov. It was noted that his research in the field of linguistics was carried out by a structural-cognitive method; it was also explained that the concept of research was aimed at analyzing language in a natural way. Thanks to the recognition of the direction of the scientist's research, the theory of the "dominant side" of the main members of the sentence, the theory of the "contextual predicate" expressed by the zero category was formulated in his work. As a result of the conducted research, it becomes clear that the methodology of A. Baitursynov's linguistics was justified by separate research and methodological, philosophical, natural science (cognitive) research methods. The scientist's work reflects the instrumental method of methodological research; the method of distributive analysis; the method of scientific sensitivity (scientific intuition). As a result of such methodological justifications and methods of methodological research, we were convinced that the linguist in his work formed a metalanguage basis that is used in the modern Kazakh language. The article also discusses the methods of methodical teaching, language methods used by the researcher in his work on linguistics, through practical analysis, interpretation, generalization, and also discusses the essence of the research results.

Spatial Distribution and Accessibility Measurements for Elderly Day Care Centers in China’s Urban Built-up Area: The Case of Tianjin Nankai District

The elderly community day care model is an emergent solution to the aging problem influenced by the Eastern perspective of family in China. Due to the structural problem of spatial disorder in most of China’s urban built-up areas, the planning and construction of elderly day care centers (EDCCs) is facing great challenges. This study aims to comprehensively compare the spatial distribution and accessibility measurement methods for elderly residents and EDCCs in typical Chinese urban built-up areas based on the accessibility theory and spatial analysis methods from the community living circle perspective. The results show that different spatial distribution analysis methods have their own emphases and limitations, requiring comprehensive application in practice. The potential model method is most suitable for the accessibility measurement in this scenario. The threshold setting of service distance for the urban built-up areas public service facilities in the current Chinese standard needs to be further optimized. The existing EDCCs suffer from serious quantity deficiencies and misplaced supplies in the region. These findings can reveal the EDCCs distribution characteristics of typical Chinese urban built-up areas and provide new insights for urban planners and policy makers who are assessing the equity and efficiency of public service facilities.

Effects of Particle Size Distribution and Impact Speed on Printing Quality in Direct Energy Deposition

Particle Size Distribution (PSD) has been studied as an important factor that will affect printing quality in selective laser sintering/melting (SLS/SLM). However, few studies investigated the effects of particle size distribution and associated impact speeds on the quality of printed surfaces in Direct Energy Deposition (DED) processes. Due to the different characteristics of powder bed and powder fed printing mechanism, particle size distribution could be evaluated before the printing but could not be assessed in-situ during the printing process of SLS/SLM. The powder stream of the DED process provides the opportunity to evaluate the PSD in-situ using a novel laser diffraction method. The laser diffraction method was a well-established particle size distribution analysis method for soil granite. It can achieve a fast, accurate, and in-situ analysis but has never been studied in DED printing. In this study, a novel laser diffraction PSD analyzer was proposed. A high-speed camera was applied to investigate the relationship between the impact speed and carrier gas flux. Stainless steel 316L metal powders with different PSDs and impact speeds were DED printed, the surface roughness and tensile strength were measured to evaluate the effects of impact speeds and PSDs on the printing quality. The results showed that impact speed and PSD had considerable influences on the printed surface roughness and tensile strength of printed parts. This study paves the way for adopting laser diffraction as an in-situ monitoring tool for the DED processes.

Numerical method for finite-size security analysis of quantum key distribution

Quantum key distribution (QKD) enables secure information exchange with untrusted quantum links between remote communication parties. A central task in the studies of QKD protocols is security analysis, which aims at deriving the length of the final key such that it is secure regardless of the eavesdropper's computational power. In literature, the security analysis has been done both analytically and numerically. Compared to analytical methods which tend to require techniques specific to each QKD protocol, numerical ones are more general since they can be directly applied to many QKD protocols with little adaptation. However, current numerical methods are carried out based on some assumptions such as working in the asymptotic limit and collective attacks from eavesdroppers. In this work, we remove these assumptions and develop a numerical finite-size security analysis against general attacks for a large class of QKD protocols. We also give an example of applying the method to the recent phase-matching QKD protocol with a simplified protocol design. Our result shows that the finite-size key rate can surpass the linear key-rate bound with a practical QKD system operated for only several hours.

Methodology for carbon emission flow calculation of integrated energy systems

Aggravation of energy shortage and global warming has raised public low-carbon awareness and promoted the development of integrated energy system (IES). However, there has not been a general method for analysis of carbon emission distribution in the IES yet. A methodology combining energy flow (EF) with carbon emission flow (CEF) is proposed in this paper to calculate and analyze the carbon emission from the IES, which is composed of AC/DC power systems and heating/cooling systems. Decoupling methods are used to improve computing efficiency with good convergence in solving energy flow equations of subsystems. A typical case is modeled and simulated using CloudPSS-IESLab platform, a high-efficient power flow solver, with calculation results and Sankey diagram demonstrating the CEF distribution in the IES.

Rockfill material segmentation and gradation calculation based on deep learning

The gradation of rockfill materials affected the rolling quality and body strength of earth-rockfill dam. To address the limitations of manual screening and traditional computer vision methods, a gradation detection method suitable for rockfill dam construction sites was proposed based on deep learning, which can output the detection results end-to-end. The method utilized the modified MASK R-CNN model to locate and segment rockfill materials. Specifically, the model used ResNeXt101 as the backbone network and adds the squeeze-and-excitation block to enhance the feature extraction capability of the model. The detection results of 500 test images showed that proposed method had high accuracy, the average precision and intersection over union value of the model reach 0.934 and 0.879. The morphological characteristics of rockfill particles were extracted by rotating calipers algorithm and used for grading calculation. Comparing this calculation method with manual screening, the results indicated that the overall fitting effect of the gradation detected by proposed method was in accord with the actual gradation parameters. The gradation of rockfill materials can be obtained within 60 s. This paper provided a new method for rapid analysis of particle size distribution, which can be used for auxiliary construction.

Intelligent Control Method for Loss Distribution Balance of High-Power Photovoltaic Grid-Connected Inverters.

Aiming at the problem that the loss distribution balance control effect of high-power photovoltaic grid-connected inverter is poor due to the complex loss factors, this paper proposes a loss distribution analysis and balance intelligent control method for high-power photovoltaic grid-connected inverter. The topology structure of high-power photovoltaic grid-connected inverter is constructed and the overall control scheme is designed. The loss of inductance, resonant frequency, harmonic attenuation, and damping resistance in the circuit of PV grid-connected inverter is analyzed, respectively. On this basis, a two-stage loss control model of high-power PV grid-connected inverter is constructed, and the generalized linear decision rule is adopted to schedule PV power supply and fluctuating load. A two-stage loss control model for high-power photovoltaic grid-connected inverter was established and the optimal loss control value was obtained. Experimental results show that the proposed method can accurately suppress voltage and current losses of grid-connected photovoltaic inverters and has strong resonance resistance and robustness.

Theoretical and Experimental Analysis of Eddy Current Contactless Speed Sensors for Linear Motor Elevators

Linear motor elevators are the strongest candidates for the next generation of elevators. They require a new method for sensitively detecting overspeed, while dispensing with the requirement of ropes that span the building that are used in conventional sensors. In this paper, we report on the theoretical and experimental analysis of a new contactless and ropeless safety device actuator system that uses electromagnetic inductive force to measure the speed of movement with good sensitivity. The sensor is mechanically actuated by eddy current forces and its operation does not depend on electrical power supplies or electronic components, making it suitable as a safety device. We describe two methods for making the speed response nonlinear, in order to increase sensitivity to overspeed. In the first, the eddy current forces are generated through a variable overlap of a magnet over a reaction plate, thus the speed–force relationship is nonlinear. In the second, the eddy current forces are modulated by the speed to obtain mechanical resonance effects. We have also developed a semi–analytic calculation method for the detailed analysis of the electromagnetic field distribution and eddy current forces in the proposed overspeed detector system, and verified it by experiments. Computed and measured values show good agreement, supporting the validity of the analysis.

Distribution analysis method of key targets based on big data analysis engine for maritime space-time trajectory

Abstract Now a large amount of maritime space-time trajectory data has been collected, but its deep value is unable to be tapped, and the analysis of the distribution of key targets has also encountered bottlenecks. The emergence of big data technology provides us with a solution. This paper proposes a big data analysis engine for maritime space-time trajectory, which makes full use of the data characteristics and improves the overall computing performance of the engine. Based on this engine, a dispersal analysis algorithm for key military targets at sea is proposed to achieve rapid retrieval and dispersal analysis of key marine targets. It has been tested and verified that this engine has excellent performance and can become an efficient query and analysis engine for maritime space-time trajectory data. The key target distribution analysis algorithm has certain research significance and practical value.

Structure-based virtual screening workflow to identify antivirals targeting HIV-1 capsid.

We have identified novel HIV-1 capsid inhibitors targeting the PF74 binding site. Acting as the building block of the HIV-1 capsid core, the HIV-1 capsid protein plays an important role in the viral life cycle and is an attractive target for antiviral development. A structure-based virtual screening workflow for hit identification was employed, which includes docking 1.6 million commercially-available drug-like compounds from the ZINC database to the capsid dimer, followed by applying two absolute binding free energy (ABFE) filters on the 500 top-ranked molecules from docking. The first employs the Binding Energy Distribution Analysis Method (BEDAM) in implicit solvent. The top-ranked compounds are then refined using the Double Decoupling method in explicit solvent. Both docking and BEDAM refinement were carried out on the IBM World Community Grid as part of the FightAIDS@Home project. Using this virtual screening workflow, we identified 24 molecules with calculated binding free energies between − 6 and − 12 kcal/mol. We performed thermal shift assays on these molecules to examine their potential effects on the stability of HIV-1 capsid hexamer and found that two compounds, ZINC520357473 and ZINC4119064 increased the melting point of the latter by 14.8 °C and 33 °C, respectively. These results support the conclusion that the two ZINC compounds are primary hits targeting the capsid dimer interface. Our simulations also suggest that the two hit molecules may bind at the capsid dimer interface by occupying a new sub-pocket that has not been exploited by existing CA inhibitors. The possible causes for why other top-scored compounds suggested by ABFE filters failed to show measurable activity are discussed.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10822-022-00446-5.

Contemporary Research Progress on the Detection of Polycyclic Aromatic Hydrocarbons.

Polycyclic aromatic hydrocarbons (PAHs) are a class of the most common and widespread contaminants. The accumulation of PAHs has made a certain impact on the environment and is seriously threatening human health. Numerous general analytical methods suitable for PAHs were developed. With the development of economy, the environmental problems of PAHs in modern society are more extensive and prominent, and attract more attention from environmental scientists and analysts. Deeper understanding of the properties of PAHs depends on the advent of detection methods, which can also be more conducive to promoting the protection of the environment. Till now, more sensitive, more high-speed and more high-throughput analytical tools are being invented and have played important roles in the research of PAHs. In this short review article, we focused mainly on the contemporary analytical methods about PAHs. We started with a brief review on the hazards, migration, distribution and traditional analysis methods of PAHs in recent years, including liquid chromatography, gas chromatography, surface enhanced Raman spectroscopy and so on. We also presented the applications of the modern ambient mass spectrometry, especially microwave plasma torch mass spectrometry, in the detection of PAHs, as well as the far out novel results in our lab by using microwave plasma torch (MPT) mass spectrometry; for example, some new insights about Birch reduction, regular hydrogen addition and the robustness of molecular structure. These studies have demonstrated the versatility of MPT MS as a platform in the research of PAHs.

WORD COMBINATION AND ABBREVIATION AS THE COMPLEX-TYPE COMPONENTS IN THE RUSSIAN LANGUAGE

Abstract &#x0D; Background. Not only word can be considered as a nominative unit of some language according to the adepts of word-centrism. Such a unit is reasonable to be considered as a certain invariant capable of containing characteristics of a word and its forms or characteristics of a word combination and its forms respectively. Nominativeness and semantic-grammatical identity of all the forms of different form and structure are the main factors to identify a linguistic invariant. Thus, it turns to be an abstract unit being separated from all its implementations; it acts as something general being present to some extent in a set of homogeneous specific units with the status of its variants or doublets. Invariants are always represented by their modifications.&#x0D; Purpose of the paper is to analyze features of abbreviations as one of the linguistic implementations of the complex-type nominathemes. The purpose has stipulated the following tasks: 1) to study motivation relations established between a word combination and its condensed equivalent; 2) to describe criteria of identity of a nominatheme with its modifications – word combinations and abbreviations.&#x0D; Methods. The research has involved a series of methods being in compliance with its topic, i.e.: method of continuous sampling to accumulate actual material; method of distributive analysis to differentiate the concepts; and descriptive method to describe and generalize the status of the units under consideration.&#x0D; Results. We tend to determine abbreviations as the words appeared as a result of verbal – synthetic – modification of a word combination, which have identical lexical and grammatical meaning as well as syntactic function and which are the result of an abbreviation process. Relations between an abbreviation and its corresponding word combination are understood as the equatable relational (form-generating) ones under conditions of semantic identity. There is a series of intralinguistic and extralinguistic reasons of the formation of abbreviations, which are similar to the formation of univerbs as well. Firstly, that is compression in word formation that is explained by the law of saving of linguistic means; it is especially clear in the colloquial speech. Secondly, it is motivated by the origin of new phenomena that require certain determination. Thirdly, there can be some reasons to change a name of something already existing. That can be stipulated by the factors from the sphere of politics, economics, communication etc. Fourthly, that is the striving to save linguistic efforts of speakers. Fifthly, it is a manifestation of compensator properties of a linguistic system.&#x0D; Discussion. A nominatheme is the main linguistic unit to be analyzed; the unit is capable of containing characteristics of a word combination and its form respectively. Eight structural varieties of a nominatheme have been singled out, along with which generally 14 varieties are available. Abbreviations as the units, in which nominathemes with a dominant-word combination of a complex type are implemented verbally, make up a great share of such structural invariants, namely: 1) word combination + abbreviation + elliptic univerb; 2) word combination + word combination of a juxtaposition-abbreviation type + elliptic univerb; 4) word combination + abbreviation-type composite + abbreviation + elliptic univerb; 5) word combination + abbreviation-type composite + elliptic univerb + elliptheme (main word) + abbreviation; 6) word combination + abbreviation-type composite + elliptheme (main word); 7) word combination + elliptic univerb + abbreviation + compressive univerb; 8) word combination + elliptic univerb + abbreviation-type composite + elliptheme (main word); 9) word combination + elliptic univerb + abbreviation + elliptheme (dependent word); 10) word combination + word combination of a juxtaposition-abbreviation type + elliptic univerb + elliptheme (main word).&#x0D; Keywords: complex-type nominatheme, abbreviation process, abbreviation, word combination, identity.

Advantages of Quantitative Analysis of Depth-Dependent Fluorescence Quenching: Case Study of BAX.

Dynamic disorder of the lipid bilayer presents a challenge for establishing structure-function relationships in membrane proteins, especially to those that insert by refolding from soluble states, e.g., bacterial toxins and Bcl-2 apoptotic regulators. Because many high-resolution structural techniques cannot be easily applied to such systems, methods like depth-dependent fluorescence quenching gained prominence. Over three decades ago, Prof. Erwin London and his co-workers revolutionized the studies of membrane protein insertion by introducing a quantitative approach to the analysis of membrane quenching data and inspired many researchers to continue this work. Here, we illustrate how the application of the quantitative analysis yields new insights into previously published results. We have used the method of distribution analysis (DA) to calculate the precise immersion depth of NBD fluorophores selectively attached to various single-cysteine mutants of the apoptotic factor BAX from quenching data obtained with a series of spin-labeled lipids. The original qualitative analysis interpreted the higher quenching determined for shallower probes in positions flanking the helix 9 of BAX as evidence of a transmembrane helix 9 topology. The quantitative DA, however, revealed that a transmembrane topology of helix 9 of BAX is unlikely, as it would require labeling sites that are only 15 residues apart in a helical conformation to be separated by a transverse distance of over 45Å.

Spanglish ecolinguistic environment as a means of sustainable development

Sustainable development of multicultural communities affected by translingualism has gained a special importance with the recognition of mixed languages within the framework of ecolinguistical methodology, which considers language communities as ecosystems. The paper aims at the ecolinguistic analysis of the relationship between language and its environment. The study implies the dual nature of language ecology (physiological and social) and the fact that the ecology of the language depends on people studying and using it, transmitting the language to others. The extensive use Spanglish is promoted by a wide range of sources, including literary texts and digital media as a form of sustainability in the American social environment. The paper enlists and discusses the features of Spanglish applying the ecological, linguistic, componential, distribution and statistical analysis methods. The study focuses on the novel Yo-Yo Boing! by Giannina Braschi and results in making certain observations on the sustainability of Spanglish societies in the USA. The paper sums up that Spanglish represents a new means of social interaction which can be described as a poststandard translingual culture serving to overcome existing environmental threats.

Relative distribution analysis in Stata

In this article, I discuss the method of relative distribution analysis and present Stata software implementing various elements of the methodology. The relative distribution is the distribution of the relative ranks that the outcomes from one distribution take on in another distribution. The methodology can be used, for example, to compare the distribution of wages between men and women. The presented software, reldist, estimates the relative cumulative distribution and the relative density, as well as the relative polarization, divergence, and other summary measures of the relative ranks. It also provides functionality such as location and shape decompositions or covariate balancing. Statistical inference is implemented in terms of influence functions and supports estimation for complex samples.

Legal Definition of Irresistible Force in the Civil Law of Russia and China

The research focus is on concept of force majeure and irresistible force as a reason to release the parties from liability for failure to perform civil obligations. The authors examine theoretical concept and legal definition of “irresistible force” and its characteristics based on legislation, legal literature and judicial practice of the Russian Federation and the People’s Republic of China. Also, the authors analyze the civil law jurisdictions on irresistible force, relatively to its ambiguity and situation with the spread of the new coronavirus infection (COVID-19) and come to the conclusion that courts in each specific case should establish irresistible force circumstances. The work uses a linguistic (philological) method, in particular, the method of distributive analysis of the terms “irresistible force” and “force majeure.” The article shows that in modern Russian law the expression “irresistible force circumstances” has more efficient terminological potential. The authors propose implementation of “irresistible force circumstances” concept in the Russian Civil Code, which would more accurately reflect the essence of this concept.

Noise reduction via three types of acoustic black holes

In the last decades, several types of ABHs, i.e. circular, annular, and rectangular ABHs, have been used for vibration attenuation. However, only the circular ABH has been studied for sound radiation. In this paper, we have thoroughly compared the radiation damage of the three types of ABHs and presented the reduction mechanism. Both the sound radiation into free space and into a cavity has been studied. The former is achieved by developing the impedance matrix method, together with the supersonic intensity to unveil the mechanism of sound radiation reduction. The latter is managed by the mid-high frequency statistical modal energy distribution analysis (SmEdA) method to fast predict the response of the plate–cavity system. Both methods are based on the Gaussian expansion method (GEM). Results show that for free space the radiation efficiency loss is caused not only by the damping effect but also by the transonic behavior of the flexural wave in the ABH region, while for cavity noise, the reduction of coupling strength, in addition to the former two reasons, is also responsible for noise reduction. By comparison it is found that the annular ABH and the rectangular one have better radiation reduction performances than the traditional circular one.

Application of terahertz spectroscopy combined with density functional theory to analysis of intermolecular weak interactions for coumarin and 6-methylcoumarin

The terahertz (THz) absorption spectra of coumarin and 6-methylcoumarin have been investigated by terahertz time-domain spectroscopy (THz-TDS) system in the frequency range from 0.4 to 2.8 THz. Density functional theory (DFT) calculations, both with and without London force dispersion corrections, have been used for the assignment of the experimental THz spectra. To thoroughly interpret the spectrum information, we used potential energy distribution (PED) method to assign the vibrational modes of the absorption peaks, and identify the origin of the absorption peaks by electrostatic potential (ESP) and van der Waals (vdW) potential distribution analysis method. The results show that absorption peaks both for coumarin and 6-methylcoumarin are caused by electrostatic interaction in the lower frequency range, while vdW interaction in the higher frequency. Moreover, the potential energy distribution of electrostatic and vdW between them is basically the same, and it led to the similarity of THz spectra between coumarin and 6-MC. This work has demonstrated that using THz spectroscopy combined with DFT calculations is an effective way to analysis of intermolecular weak interactions and biomolecules with similar structures.