Computational Micrograph Registration with Sieve Processes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100164660 ◽

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.

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ЛАНДШАФТНАЯ ОРГАНИЗАЦИЯ БЕРЕГОВОЙ ГЕОСТРУКТУРЫ ОСТРОВА ШКОТА (ЗАЛИВ ПЕТРА ВЕЛИКОГО)

10.33833/tig.2019.65.23.006 ◽

2019 ◽

Author(s):

K.S. Ganzei ◽

V.V. Zharikov ◽

N.F. Pshenichnikova ◽

A.M. Lebedev ◽

A.G. Kiselyova ◽

...

Keyword(s):

Spatial Organization ◽

Peter The Great Bay ◽

Spatial Arrangement ◽

Water Area ◽

Marine Spatial Planning ◽

Landscape Approach ◽

Important Condition ◽

Statistical Comparison ◽

Peter The Great ◽

Comprehensive Study

Важнейшим условием достижения устойчивого развития прибрежноморского природопользования в заливе Петра Великого системы является морское пространственное планирование. Основой для этого является информация о природных комплексах территории и акватории, полученная на основе ландшафтного подхода. Ключевым районом для изучения пространственной организации ландшафтов прибрежных геоструктур стала территория острова Шкота и его подводных склонов. Для наземных ландшафтов было описано 49 наблюдательных пунктов, 4 профиля были заложены для подводных ландшафтов описано 64 наблюдательных пункта, проложено 18 профилей. Выделено 22 вида ландшафтов, из них 16 наземных, 6 подводных. Берега острова сформированы преобладанием абразивноденудационного и абразивного типов. В результате всестороннего изучения показаны особенности пространственной организации воздушных и водных природных комплексов. Особенностью исследуемой территории является экспозиция дифференциации ландшафтов между юговосточной и северозападной частями острова, обусловленная муссонной природой климата. Результаты полевых и картографических работ послужили основой для выбора зон интенсивного, умеренного и ослабленного взаимодействия наземных и подводных ландшафтов. Пространственное расположение зон взаимодействия четко иллюстрируется значительными различиями экспозиции. Результаты статистического сравнения ландшафтов суши и мелководья, окружающего остров, на основе картометрических характеристик указывают на неоднородность геоструктуры острова, обусловленную, прежде всего, сочетанием ландшафтообразующих факторов. The most important condition for achieving sustainable development of coastalmarine environmental management in Peter the Great Bay is marine spatial planning. The basis for this is information about the natural complexes of the territory and water area, obtained based on the landscape approach. The main area for studying the spatial organization of landscapes of coastal geostructures was the territory of the island of Shkota and its underwater slopes. For terrestrial landscapes, 49 observation points were described, 4 profiles were laid 64 observation points were described for underwater landscapes, 18 profiles were laid. 22 species of landscapes have been identified, of which 16 are terrestrial, 6 are underwater. The shores of the island are formed by the predominance of abrasivedenudation and abrasive types. Because of a comprehensive study, features of the spatial organization of air and aquatic natural complexes are shown. A special feature of the study area is the exposure of the differentiation of landscapes between the southeastern and northwestern parts of the island, due to the monsoon nature of the climate. The results of field and cartographic works served as the basis for selecting areas of intense, moderate and weakened interaction of land and underwater landscapes. The spatial arrangement of the interaction zones is clearly illustrated by significant differences in exposure. The results of a statistical comparison of the land and shallow water landscapes surrounding the island, based on the cartometric characteristics, indicate the heterogeneity of the islands geostructure, primarily due to the combination of landscapeforming factors.

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Three-dimensional electron microscopy of ribosomal chromatin in two higher plants: a cytochemical, immunocytochemical, and in situ hybridization approach.

Journal of Histochemistry & Cytochemistry ◽

10.1177/39.11.1918926 ◽

1991 ◽

Vol 39 (11) ◽

pp. 1495-1506 ◽

Cited By ~ 22

Author(s):

P M Motte ◽

R Loppes ◽

M Menager ◽

R Deltour

Keyword(s):

Electron Microscopy ◽

In Situ Hybridization ◽

Spatial Organization ◽

Higher Plants ◽

Three Dimensional ◽

Spatial Arrangement ◽

Thin Sections ◽

Cytoplasmic Dna ◽

Immunocytochemical Techniques

We report the 3-D arrangement of DNA within the nucleolar subcomponents from two evolutionary distant higher plants, Zea mays and Sinapis alba. These species are particularly convenient to study the spatial organization of plant intranucleolar DNA, since their nucleoli have been previously reconstructed in 3-D from serial ultra-thin sections. We used the osmium ammine-B complex (a specific DNA stain) on thick sections of Lowicryl-embedded root fragments. Immunocytochemical techniques using anti-DNA antibodies and rDNA/rDNA in situ hybridization were also applied on ultra-thin sections. We showed on tilted images that the OA-B stains DNA throughout the whole thickness of the section. In addition, very low quantities of cytoplasmic DNA were stained by this complex, which is now the best DNA stain used in electron microscopy. Within the nucleoli the DNA was localized in the fibrillar centers, where large clumps of dense chromatin were also visible. In the two plant species intranucleolar chromatin forms a complex network with strands partially linked to chromosomal nucleolar-organizing regions identified by in situ hybridization. This study describes for the first time the spatial arrangement of the intranucleolar chromatin in nucleoli of higher plants using high-resolution techniques.

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Alteration of nuclear architecture in male germ cells of chromosomally derived subfertile mice

Journal of Cell Science ◽

10.1242/jcs.114.24.4429 ◽

2001 ◽

Vol 114 (24) ◽

pp. 4429-4434

Author(s):

Silvia Garagna ◽

Maurizio Zuccotti ◽

Alan Thornhill ◽

Raul Fernandez-Donoso ◽

Soledad Berrios ◽

...

Keyword(s):

Sertoli Cells ◽

Spatial Organization ◽

Nuclear Architecture ◽

Spatial Arrangement ◽

Cell Types ◽

Condensed State ◽

Germ Cell Differentiation ◽

Y Chromosomes ◽

Dual Colour ◽

Pachytene Spermatocytes

The mammalian cell nucleus consists of numerous compartments involved in the regular unfolding of processes such as DNA replication and transcription, RNA maturation, protein synthesis and cell division. Knowledge is increasing of the relationships between high-order levels of chromatin organization and its spatial organization, and of how these relationships contribute to the various functions carried out in the nucleus. We have studied the spatial arrangement of mouse telocentric chromosomes 5, 11, 13, 15, 16 and 17, some of their metacentric Robertsonian derivatives, and X and Y chromosomes by whole chromosome painting in male germ (spermatogonia, pachytene spermatocytes and spermatids) and Sertoli cells of homozygous and heterozygous individuals. Using dual-colour fluorescence in situ hybridization we found that these chromosomes occupy specific nuclear territories in each cell type analysed. When chromosomes are present as Robertsonian metacentrics in the heterozygous state, that is, as Robertsonian metacentrics and their homologous telocentrics, differences in their nuclear positions are detectable: heterozygosity regularly produces a change in the nuclear position of one of the two homologous telocentrics in all the cell types studied. In the Robertsonian heterozygotes, the vast majority of the Sertoli cells show the sex chromosomes in a condensed state, whereas they appear decondensed in the Robertsonian homozygotes. As the Robertsonian heterozygosities we studied produce a chromosomally derived impairment of male germ-cell differentiation, we discuss the possibility that changes in chromosome spatial territories may alter some nuclear machinery (e.g., synapsis, differential gene expression) important for the correct unfolding of the meiotic process and for the proper functioning of Sertoli cells.

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Frequencies in vibrating wood – Does cell organization matter?

IAWA Journal ◽

10.1163/22941932-40190239 ◽

2019 ◽

Vol 40 (1) ◽

pp. 124-142

Author(s):

Oliver Dünisch

Keyword(s):

Spatial Organization ◽

Ring Width ◽

Spatial Arrangement ◽

Cell Types ◽

Dominant Frequency ◽

Fast Fourier Transformation ◽

Frequency Spectra ◽

Laser Sensors ◽

Vibrating Plates ◽

Dominant Frequencies

ABSTRACT The relationship between the spatial organization of different cell types, of the xylem rays, and of the tree rings and the frequencies in vibrating softwoods and hardwoods was studied under controlled conditions. In total, the frequencies in 1007 standardized vibrating plates from 16 softwoods and 74 hardwoods were analysed using high resolution laser sensors (accuracy ± 0.02 μm, sampling frequency 30 kHz) for vibration measurements. Overlapping frequencies within the frequency spectra were identified by means of Fast Fourier Transformation analysis. With regard to the number of distinct frequencies within the spectra, four different vibration types were identified: type 1–one dominant frequency within the frequency spectra; type 2-two dominant frequencies within the frequency spectra; type 3-three dominant frequencies within the frequency spectra; type 4-no dominant frequencies within the frequency spectra. The presence of distinct frequencies was correlated with a highly organized spatial arrangement of tracheids in softwoods, with a storied arrangement of the xylem rays in hardwoods, and with low variation in tree-ring width in both softwoods and hardwoods. The grid size for repetition in these xylem structures influenced the frequencies of the vibrating wood in absolute numbers. The results indicate that the analysis of the anatomical structure of the wood can contribute to the grading of timber for its vibration characteristics, which is of special interest for the selection of resonance wood for musical instruments.

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An efficient algorithm for finding the minimum norm point in the convex hull of a finite point set in the plane

Operations Research Letters ◽

10.1016/0167-6377(94)90019-1 ◽

1994 ◽

Vol 16 (1) ◽

pp. 33-40 ◽

Cited By ~ 3

Author(s):

Naoki Makimoto ◽

Ikuo Nakagawa ◽

Akihisa Tamura

Keyword(s):

Convex Hull ◽

Efficient Algorithm ◽

Minimum Norm ◽

Finite Point ◽

Point Set

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Spatial organization of soil microaggregates

10.5194/egusphere-egu2020-22405 ◽

2020 ◽

Author(s):

Eva Lehndorff ◽

Nele Meyer ◽

Andrey Radionov ◽

Lutz Plümmer ◽

Peter Rottmann ◽

...

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Spatial Organization ◽

Inorganic Compounds ◽

Spatial Relationship ◽

Clay Content ◽

Spatial Arrangement ◽

C Sequestration ◽

Spatial Correlations ◽

Soil Minerals

<p>The physical arrangement of soil compounds in microaggregates is important in many ways, e.g. by controlling soil stability and C sequestration. However, little is known about the spatial arrangement of organic and inorganic compounds in soil microaggregates, due to the lack of in-situ analyses in undisturbed material. Here we hypothesize that microaggregates are spatially organized, resulting in deterministic, predictable spatial patterns of different organic matter and mineral phases and that this organization depends on the abundance of specific phases such as on clay mineral content. We separated the water stable, occluded large and small microaggregate fractions from Ap horizons of a sequence of sandy to loamy Luvisols (19 to 35% clay, Scheyern, Germany) and subjected in total 60 individual aggregates to elemental mapping by electron probe micro analysis (EPMA), which recorded C, N, P, Al, Fe, Ca, K, Cl, and Si contents at &#181;m scale resolution. Spatial arrangements of soil organic matter and soil minerals were extracted using cluster analyses. We found a pronounced heterogeneity in aggregate structure and composition, which was not reproducible and largely independent from clay content in soil. However, neighborhood analyses revealed close spatial correlations between organic matter debris (C:N app. 100:10) and microbial organic matter (C:N app. 10:1) indicating a spatial relationship between source and consumer. There was no systematic relationship between soil minerals and organic matter, suggesting that well-established macroscale correlations between contents of pedogenic oxides and clay minerals with soil organic matter storage do not apply to soil microaggregates.</p>

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Clustering as Determined by Exposure Time and Spatial Arrangement of Objects

Psychological Reports ◽

10.2466/pr0.1975.37.1.159 ◽

1975 ◽

Vol 37 (1) ◽

pp. 159-166 ◽

Cited By ~ 1

Author(s):

Henry I. Stukuls

Keyword(s):

Free Recall ◽

Exposure Time ◽

Spatial Organization ◽

Visual Display ◽

Spatial Arrangement ◽

Total Recall ◽

Organizational Process ◽

The Right

The two studies extended the principles of clustering to nonverbal stimuli. College Ss were asked to learn and recall random objects under varied conditions of exposure time and spatial organization. Increments in exposure time produced increments in total recall and clustering. Also the spatial organization of stimuli facilitated total recall and the organizational process in memory. The greatest amount of recall and clustering occurred with objects from the left as opposed to the right side of the visual display and increased spatial organization of relatively random display produced increased amounts of clustering in free recall. These data for 72 students were interpreted in terms of the associationistic (Jenkins, 1952) and the mediational (Bousfield, 1953) views of clustering.

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Immuocytochemical analysis of spatial organization of photoreceptors and amacrine and ganglion cells in the tiger salamander retina

Visual Neuroscience ◽

10.1017/s0952523804042075 ◽

2004 ◽

Vol 21 (2) ◽

pp. 157-166 ◽

Cited By ~ 16

Author(s):

JIAN ZHANG ◽

ZHUO YANG ◽

SAMUEL M. WU

Keyword(s):

Ganglion Cell ◽

Spatial Organization ◽

Ganglion Cells ◽

Electrophysiological Study ◽

Outer Nuclear Layer ◽

Amacrine Cells ◽

Spatial Arrangement ◽

Cell Types ◽

Proximal Region ◽

Dorsal Retina

In the present study, using double- or triple-label immunocytochemistry in conjunction with confocal microscopy, we aimed to examine the population and distribution of photoreceptors, GABAergic and glycinergic amacrine cells, and ganglion cells, which are basic but important parameters for studying the structure–function relationship of the salamander retina. We found that the outer nuclear layer (ONL) contained 82,019 ± 3203 photoreceptors, of which 52% were rods and 48% were cones. The density of photoreceptors peaked at ∼8000 cells/mm2 in the ventral and dropped to ∼4000 cells/mm2 in the dorsal retina. In addition, the rod/cone ratio was less than 1 in the central retina but larger than 1 in the periphery. Moreover, in the proximal region of the inner nuclear layer (INL3), the total number of cells was 50,576 ± 8400. GABAergic and glycinergic amacrine cells made up approximately 78% of all cells in this layer, including 43% GABAergic, 32% glycinergic, and 3% GABA/glycine colocalized amacrine cells. The density of these amacrine cells was ∼6500 cells/mm2 in the ventral and ∼3200 cells/mm2 in the dorsal area. The ratio of GABAergic to glycinergic amacrine cells was larger than 1. Furthermore, in the ganglion cell layer (GCL), among a total of 36,007 ± 2010 cells, ganglion cells accounted for 65.7 ± 1.5% of the total cells, whereas displaced GABAergic and glycinergic amacrine cells comprised about 4% of the cells in this layer. The ganglion cell density was ∼1800 cells/mm2 in the ventral and ∼600 cells/mm2 in the dorsal retina. Our data demonstrate that all three major cell types are not uniformly distributed across the salamander retina. Instead, they exhibit a higher density in the ventral than in the dorsal retina and their spatial arrangement is associated with the retinal topography. These findings provide a basic anatomical reference for the electrophysiological study of this species.

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THE POINT-SET EMBEDDABILITY PROBLEM FOR PLANE GRAPHS

International Journal of Computational Geometry & Applications ◽

10.1142/s0218195913600091 ◽

2013 ◽

Vol 23 (04n05) ◽

pp. 357-395 ◽

Cited By ~ 1

Author(s):

THERESE BIEDL ◽

MARTIN VATSHELLE

Keyword(s):

Planar Graph ◽

Planar Graphs ◽

Line Drawing ◽

Np Hard ◽

Bounded Treewidth ◽

Straight Line ◽

Triangulated Graphs ◽

Point Set ◽

Fixed Embedding ◽

Set Of Points

In this paper, we study the point-set embeddability problem, i.e., given a planar graph and a set of points, is there a mapping of the vertices to the points such that the resulting straight-line drawing is planar? It was known that this problem is NP-hard if the embedding can be chosen, but becomes polynomial for triangulated graphs of treewidth 3. We show here that in fact it can be answered for all planar graphs with a fixed combinatorial embedding that have constant treewidth and constant face-degree. We prove that as soon as one of the conditions is dropped (i.e., either the treewidth is unbounded or some faces have large degrees), point-set embeddability with a fixed embedding becomes NP-hard. The NP-hardness holds even for a 3-connected planar graph with constant treewidth, triangulated planar graphs, or 2-connected outer-planar graphs. These results also show that the convex point-set embeddability problem (where faces must be convex) is NP-hard, but we prove that it becomes polynomial if the graph has bounded treewidth and bounded maximum degree.

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