scholarly journals Whether the pairwise rating method and the Spatial Arrangement Method yield comparable dimensionalities depends on the dimensionality choice procedure

2021 ◽  
pp. 100060
Author(s):  
Steven Verheyen ◽  
Gert Storms
Keyword(s):  
Spatial Arrangement ◽  
Choice Procedure ◽  
Rating Method ◽  
Method Yield

Whether the Pairwise Rating Method and the Spatial Arrangement Method Yield Comparable Dimensionalities Depends on the Dimensionality Choice Procedure

2020 ◽  
Author(s):  
Steven Verheyen ◽  
Gert Storms
Keyword(s):  
Spatial Arrangement ◽  
Systematic Investigation ◽  
Two Dimensions ◽  
Similarity Measurement ◽  
Semantic Categories ◽  
Similarity Data ◽  
Choice Procedure ◽  
Rating Method ◽  
Method Yield ◽  
Data Yield

We investigate whether two methods for obtaining similarity data yield multidimensional scaling (MDS) solutions of comparable dimensionality. In the Pairwise Rating Method (PRaM), participants rate the (dis)similarity of all pairs of stimuli on a Likert scale. In the Spatial Arrangement Method (SpAM), participants organize stimuli on a computer screen so that the distance between stimuli represents their perceived dissimilarity. Across two studies that included eight semantic categories with varying numbers of both pictorial and verbal exemplars, we did not find consistent dimensionality differences between the two similarity measurement methods. The results alleviate the concern that because of its two-dimensional nature, SpAM might underestimate the dimensionality of high-dimensional stimuli compared to PRaM. Aggregating the SpAM similarity data from a sufficient number of participants can yield spatial representations with more than two dimensions. However, the resulting number of dimensions was found to be highly dependent on the dimensionality choice procedure. Even for specific combinations of a single category and similarity measurement method, different dimensionalities were obtained depending on whether the reliability of the similarity data, Monte Carlo simulations, or predictive correlations were used to establish the number of dimensions, indicating the need for a more systematic investigation into dimensionality selection for MDS.

Conformation of Ribosomes from Escherichia Coli

1974 ◽  
Vol 32 ◽  
pp. 210-211
Author(s):  
M. Boublik ◽  
W. Hellmann ◽  
F. Jenkins
Keyword(s):  
Binding Sites ◽  
Ribosomal Proteins ◽  
Fluorescent Dyes ◽  
Protein Biosynthesis ◽  
Three Dimensional ◽  
Spatial Arrangement ◽  
Dimensional Structure ◽  
Complete Understanding ◽  
And Function

The present knowledge of the three-dimensional structure of ribosomes is far too limited to enable a complete understanding of the various roles which ribosomes play in protein biosynthesis. The spatial arrangement of proteins and ribonuclec acids in ribosomes can be analysed in many ways. Determination of binding sites for individual proteins on ribonuclec acid and locations of the mutual positions of proteins on the ribosome using labeling with fluorescent dyes, cross-linking reagents, neutron-diffraction or antibodies against ribosomal proteins seem to be most successful approaches. Structure and function of ribosomes can be correlated be depleting the complete ribosomes of some proteins to the functionally inactive core and by subsequent partial reconstitution in order to regain active ribosomal particles.

Structural organization of escherichia coli ribosomes as determined by immuno electron microscopy

1978 ◽  
Vol 36 (2) ◽  
pp. 166-167 ◽  
Author(s):  
G. Stöffler ◽  
R.W. Bald ◽  
J. Dieckhoff ◽  
H. Eckhard ◽  
R. Lührmann ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Escherichia Coli ◽  
Ribosomal Proteins ◽  
Structural Organization ◽  
Three Dimensional ◽  
Ribosomal Subunit ◽  
Spatial Arrangement ◽  
Small Subunit ◽  
Antibody Binding ◽  
Immuno Electron Microscopy

A central step towards an understanding of the structure and function of the Escherichia coli ribosome, a large multicomponent assembly, is the elucidation of the spatial arrangement of its 54 proteins and its three rRNA molecules. The structural organization of ribosomal components has been investigated by a number of experimental approaches. Specific antibodies directed against each of the 54 ribosomal proteins of Escherichia coli have been performed to examine antibody-subunit complexes by electron microscopy. The position of the bound antibody, specific for a particular protein, can be determined; it indicates the location of the corresponding protein on the ribosomal surface.The three-dimensional distribution of each of the 21 small subunit proteins on the ribosomal surface has been determined by immuno electron microscopy: the 21 proteins have been found exposed with altogether 43 antibody binding sites. Each one of 12 proteins showed antibody binding at remote positions on the subunit surface, indicating highly extended conformations of the proteins concerned within the 30S ribosomal subunit; the remaining proteins are, however, not necessarily globular in shape (Fig. 1).

Colloidal systems in soils

1994 ◽  
Vol 52 ◽  
pp. 64-65
Author(s):  
J. Thieme ◽  
J. Niemeyer ◽  
P. Guttman
Keyword(s):  
Clay Minerals ◽  
Polymeric Materials ◽  
Spatial Arrangement ◽  
High Specific Surface Area ◽  
Turnover Rates ◽  
Colloidal Systems ◽  
Chemical Conditions ◽  
Aggregation Phenomena ◽  
Iron And Manganese ◽  
Soil Colloids

In soil science the fraction of colloids in soils is understood as particles with diameters smaller than 2μm. Clay minerals, aquoxides of iron and manganese, humic substances, and other polymeric materials are found in this fraction. The spatial arrangement (microstructure) is controlled by the substantial structure of the colloids, by the chemical composition of the soil solution, and by thesoil biota. This microstructure determines among other things the diffusive mass flow within the soils and as a result the availability of substances for chemical and microbiological reactions. The turnover of nutrients, the adsorption of toxicants and the weathering of soil clay minerals are examples of these surface mediated reactions. Due to their high specific surface area, the soil colloids are the most reactive species in this respect. Under the chemical conditions in soils, these minerals are associated in larger aggregates. The accessibility of reactive sites for these reactions on the surface of the colloids is reduced by this aggregation. To determine the turnover rates of chemicals within these aggregates it is highly desirable to visualize directly these aggregation phenomena.

Computational Micrograph Registration with Sieve Processes

1996 ◽  
Vol 54 ◽  
pp. 440-441
Author(s):  
P.J. Phillips ◽  
J. Huang ◽  
S. M. Dunn
Keyword(s):  
Planar Graph ◽  
Efficient Algorithm ◽  
Spatial Organization ◽  
Spatial Arrangement ◽  
Stereo Image ◽  
Image Model ◽  
Geometric Invariants ◽  
Point Set

In this paper we present an efficient algorithm for automatically finding the correspondence between pairs of stereo micrographs, the key step in forming a stereo image. The computation burden in this problem is solving for the optimal mapping and transformation between the two micrographs. In this paper, we present a sieve algorithm for efficiently estimating the transformation and correspondence.In a sieve algorithm, a sequence of stages gradually reduce the number of transformations and correspondences that need to be examined, i.e., the analogy of sieving through the set of mappings with gradually finer meshes until the answer is found. The set of sieves is derived from an image model, here a planar graph that encodes the spatial organization of the features. In the sieve algorithm, the graph represents the spatial arrangement of objects in the image. The algorithm for finding the correspondence restricts its attention to the graph, with the correspondence being found by a combination of graph matchings, point set matching and geometric invariants.

Underlying Structure of Auditory-Visual Consonant Perception by Hearing-Impaired Children and the Influences of Syllabic Compression

1988 ◽  
Vol 31 (2) ◽  
pp. 156-165 ◽  
Author(s):  
P. A. Busby ◽  
Y. C. Tong ◽  
G. M. Clark
Keyword(s):  
Hearing Aids ◽  
Free Field ◽  
Acoustic Parameter ◽  
Hearing Impaired ◽  
Visual Signal ◽  
Underlying Structure ◽  
Choice Procedure ◽  
Release Times ◽  
Impaired Children ◽  
Hearing Impaired Children

The identification of consonants in a/-C-/a/nonsense syllables, using a fourteen-alternative forced-choice procedure, was examined in 4 profoundly hearing-impaired children under five conditions: audition alone using hearing aids in free-field (A),vision alone (V), auditory-visual using hearing aids in free-field (AV1), auditory-visual with linear amplification (AV2), and auditory-visual with syllabic compression (AV3). In the AV2 and AV3 conditions, acoustic signals were binaurally presented by magnetic or acoustic coupling to the subjects' hearing aids. The syllabic compressor had a compression ratio of 10:1, and attack and release times were 1.2 ms and 60 ms. The confusion matrices were subjected to two analysis methods: hierarchical clustering and information transmission analysis using articulatory features. The same general conclusions were drawn on the basis of results obtained from either analysis method. The results indicated better performance in the V condition than in the A condition. In the three AV conditions, the subjects predominately combined the acoustic parameter of voicing with the visual signal. No consistent differences were recorded across the three AV conditions. Syllabic compression did not, therefore, appear to have a significant influence on AV perception for these children. A high degree of subject variability was recorded for the A and three AV conditions, but not for the V condition.

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