Interaction Of Different Systems Research Articles

Density-dependent interactions in an Arctic char – brown trout system: competition, predation, or both?

In the study of mechanisms structuring fish communities, mixed competition–predation interactions where large predators feed on prey fish versus those in which small predators compete with prey fish for a shared prey have been the focus of substantial research. We used a long-term data set from a system inhabited by brown trout (Salmo trutta) (predator) and Arctic char (Salvelinus alpinus) (prey) to evaluate whether mixed interspecific interactions were present in this system as suggested in other studies focusing on this species pair. We found no evidence for a negative interspecific density dependence in individual performance in either Arctic char or brown trout. In contrast, a negative intraspecific density dependence was present, especially in Arctic char. Furthermore, large brown trout condition showed a positive response to encounter rate with Arctic char (related to the density of small Arctic char). The most parsimonious interaction module to explain the Arctic char – brown trout interaction patterns in the studied system does therefore not need to include interspecific competition. We suggest that size-structured mixed competition–predation interactions in different systems are realized as being either mainly structured through interspecific predation or by competition depending on species life history characteristics and environmental conditions.

Joyce L.C.Ma, Anorexia Nervosa and Family Therapy in a Chinese Context. Hong Kong: Chinese University Press, 2011. 272pp., 9629964600. £26.95

Joyce L.C.Ma, Anorexia Nervosa and Family Therapy in a Chinese Context. Hong Kong: Chinese University Press, 2011. 272pp., 9629964600. £26.95

Characterizing Cell–Cell Interactions Induced Spatial Organization of Cell Phenotypes: Application to Density-Dependent Protein Nucleocytoplasmic Distribution

Cell-cell interactions play an important role in spatial organization (pattern formation) during the development of multicellular organisms. An understanding of these biological roles requires identifying cell phenotypes that are regulated by cell-cell interactions and characterizing the spatial organizations of the phenotypes. However, conventional methods for assaying cell-cell interactions are mainly applicable at a cell population level. These measures are incapable of elucidating the spatial organizations of the phenotypes, resulting in an incomplete view of cell-cell interactions. To overcome this issue, we developed an automated image-based method to investigate cell-cell interactions based on spatial localizations of cells. We demonstrated this method in cultured cells using cell density-dependent nucleocytoplasmic distribution of β-catenin and aryl hydrocarbon receptor as the phenotype. This novel method was validated by comparing with a conventional population-based method, and proved to be more sensitive and reliable. The application of the method characterized how the phenotypes were spatially organized in a population of cultured cells. We further showed that the spatial organization was governed by cell density and was protein-specific. This automated method is very simple, and will be applicable to study cell-cell interactions in different systems from prokaryotic colonies to multicellular organisms. We envision that the ability to extract and interpret how cell-cell interactions determine the spatial organization of a cell phenotype will provide new insights into biology that may be missed by traditional population-averaged studies.

Managing subsystem interfaces of complex products

An interface management model for multidisciplinary products is proposed with the aim of improving communication between design groups. The systematic methodology described in this paper captures the interaction of different systems in an object oriented model. This helps to define the connectivity of subsystems such that the effect of modifications is more visible to designers. With the use of common definitions and greater visibility of the impact of changes, the number of incompatible design decisions is reduced. This results in lower product development times and eases subsystem modifications. Interfaces are modelled using object oriented technology since this parallels the object nature of product data and since object technology provides a formalised way of integrating interfaces into product data management software.

Thermolinguistics and human thermodynamics. Correspondence principles

We consider the analogy between molecules and objects of linguistics (and other semiotic systems). We establish the correspondence principle between the thermodynamics of supercritical states and linguistics. Certain laws of thermolinguistics are formulated. The problem of pairwise interaction in different systems is discussed.

Zum Transfer kulturspezifischer Textbedeutungen. Theoretische und methodische Überlegungen aus einer semiotischen Perspektive

This paper discusses the role of cultural specific text elements in the constitution of the meaning of the text and focuses the problems which these elements can cause in the translation process. It is based on a description of the translation process as symbiosis of the three categories language, text and culture in a specific situation. The described comprehension of translation turns the question of the methodology of the cultural transfer into a key question that consequently has an impact on the praxis and didactics of translation. The meaning of a text is the result of a complex interaction of different systems in which different types of knowledge are activated. The central question is how culture manifests itself within texts and how these manifestations can be reconstructed, i.e. how the translator's decisions can be made transparent in the context of the transfer. Firstly there is a theoretical reflection on the interdependence of the three categories language, culture and text in which the underlying semiotic conception of text and culture is outlined. On this basis a pragma-semiotic model of the constitution of the text as a complex sign is presented, and a methodology for an integrative text analysis is deduced from this theoretical conception of text constitution. The different forms of cultural specific elements are analyzed and categorized, whereas in addition to the traditional manifestations the concept of intertextuality is introduced and discussed as an important fact for the pragmatic and cultural coherence of the text. The defined forms of cultural specific text elements are illustrated by a number of examples taken from translation praxis and classroom. All the examples are translations from Spanish into German. Finally, the practical and didactical implications, which are of great importance for the training of further translators, are discussed.

Extending Broyden's method to interaction problems

The solution of problems involving the interaction of different systems is a domain of ongoing research, although often a good solver already exists for each system separately. In this paper we draw our ideas from one of the best known all-round quasi-Newton methods: Broyden's rank-one update, which we extend to algorithms using 2 approximate Jacobians. A comparison is made with the iterative substructuring method and Aitken's acceleration method. It is shown that a Broyden method using only a single approximate Jacobian performs best.

Interaction of aminoacyl-tRNA synthetases with tRNA: General principles and distinguishing characteristics of the high-molecular-weight substrate recognition

This review summarizes results of numerous (mainly functional) studies that have been accumulated over recent years on the problem of tRNA recognition by aminoacyl-tRNA synthetases. Development and employment of approaches that use synthetic mutant and chimeric tRNAs have demonstrated general principles underlying highly specific interaction in different systems. The specificity of interaction is determined by a certain number of nucleotides and structural elements of tRNA (constituting the set of recognition elements or specificity determinants), which are characteristic of each pair. Crystallographic structures available for many systems provide the details of the molecular basis of selective interaction. Diversity and identity of biochemical functions of the recognition elements make substantial contribution to the specificity of such interactions.

Vestibular folds configuration in vocal nodule

Vocal nodules are among the most common laryngopathies that cause vocal functional disorders. The voice production mechanism is complex and demand interaction of different systems of the human body. The physiological role of the vocal folds as the glottic sound source is evident, however, there is no consensus regarding the vestibular folds' participation/influence in phonation. To verify if there is difference in the bidimensional configuration of the vestibular folds between two distinct groups of women, one with the diagnosis of vocal nodules and the other without vocal complaints and vocal fold lesions. Clinical with transversal cohort. Ninety-six laryngeal images were evaluated, 48 from individuals without vocal complaints and 48 from patients with the diagnosis of vocal nodules. Angles were obtained and bilaterally measured in single frames of the vestibular folds during sustained phonation and those structures were morphologically classified as concave, linear or convex. Among the 96 vestibular folds evaluated in each group, there was predominance of the concave form, followed by the linear and the convex ones. In the control group, there was a single convex vestibular fold, 27 were linear and 68 were concave folds. In the group of vocal nodules, 8 were convex, 15 were linear and 73 were concave folds. However, the differences among groups were not statistically significant as well as those among the angles, whose average measures were proven quite similar. In the female gender, the vestibular folds presented similar behavior regarding the morphology in both patients with vocal nodules and women without vocal complaints.

Metal Ligand Aromatic Cation—π Interactions

AbstractFor Abstract see ChemInform Abstract in Full Text.

Metal Ligand Aromatic Cation−π Interactions

AbstractCation−π interactions are important noncovalent bonding forces. This review covers a special type of cation−π interactions, the metal ligand aromatic cation−π (MLACπ) interaction, where ligands that are coordinated to a metal ion interact with aromatic groups. These interactions have been observed in metalloproteins, metal complexes, biomimetic metal complexes, and when DNA and RNA interact with metal cations. The energy of MLACπ interactions in different systems has been calculated by quantum chemical methods and was found to vary from 1 to 30 kcal/mol. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

Child maltreatment in Greece: a review of research

Child maltreatment can be traced in Greek mythology, history and literature. Greek society has always used passive or active violence towards its dependent members, including children. In the last 17 years there have been a number of studies describing child maltreatment in contemporary Greece. Most have used small clinical samples; nevertheless, their findings are comparable to those of other countries and their results support the psychopathological causality of child maltreatment. A number of studies on child-rearing practices and on children's socialization have revealed an extensive use of physical punishment related to the child's opposition to parental authority and high parental expectations often linked with the child's school performance. Another small set of studies assessed the effectiveness of social policy and the appropriateness of the child protection system. On the basis of the studies on child maltreatment in Greece, the author proposes firstly the adoption of an operational definition which takes into consideration community attitudes and culture. A second proposal relates to the application of an ecological theoretical model stressing the mutual interaction of different systems and their cumulative effects. Lastly, it is suggested that social policy measures should be introduced in the field of primary, secondary and tertiary prevention. © 1997 John Wiley & Sons, Ltd.

Voltammetric approach to multicomponent electrochemical systems at platinum electrode surfaces

Adsorption interactions of different systems on electrodispersed and smooth platinum electrodes were explored through anodic stripping voltammetry using a conventional flow cell technique at 25°C. A first adsorbate was formed at the platinum electrode in contact with the solution containing the adsorbable species I, and subsequently the platinum—adsorbate I system was put into contact with a solution containing the adsorbable species II, where I  CO, CH 3OH and reduced CO 2, and II C 2H 4, C 2H 2 and CO, and vice versa. The anodic stripping voltammograms revealed either a total or partial displacement of adsorbate I by adsorbate II, or chemical interactions among adsorbed residues I and Il. The following decreasing platinum—adsorbate interaction sequence was established C 2H 2-2 > CO > C 2H 4 > CH 3OH ≈ CO 2.

Microfilament-membrane interaction

One of the major topics of research in modern cell biology involves the structure and organization of the cytoskeleton and, in particular, the interaction of its various components with the plasma membrane. Studies carried out in many laboratories over the last several years pointed to the complex and heterogeneous nature of membrane-cytoskeleton interactions in different systems. This is manifested by a remarkable cell-type specificity as well as distinct differences between the mode of anchorage of the various cytoskeletal components. Moreover the assembly and maintenance of each of the cytoskeletal systems within individual cells appears to be a dynamic process which is probably spatially and temporally regulated and modulated.

Multisensory interaction in the torus semicircularis of the clawed toad Xenopus laevis

Interactions between the lateral-line, general somatosensory and auditory system were studied using field potential analysis and single unit recordings in the torus semicircularis of the clawed toad Xenopus laevis. As a response to paired stimuli (electric shocks applied to the peripheral nerves or acoustic clicks), in all systems a reduction of the second evoked potential occurred for intervals of up to 5 s. Following consecutive stimulation of two different systems, the amplitude of the second evoked potential was also reduced, indicating mutual interaction of different systems. Single unit recordings revealed the existence of both inhibitory and excitatory interaction between different modalities.