Mark
Dow
Example Space Software renderings
Quail chick, MRI
Quail chick, volume rendered from MRI data. Coturnix japonicus, embryonic age 10 days, ex ovo.

(stereo pair, cross view)
Raw volume data available from Caltech Atlas of Quail Development (data © California Institute of Technology, Pasadena).
Quail and human vision hardware
Comparison of MRI slices through the optic nerves of a quail chick and an adult human, scaled so the slice areas are about equal.
The optic nerves of all vertebrates cross at the optic chiasm, at midline behind the eyes near the mid-brain structures.
The
zipper-like structure extending into the quail eye is a mystery to me.
It appears to be an extension of the optic nerve into the retina (or
what the retina develops from), but I've never seen an illustration of
vertebrate eye development that shows anything like it. Another view of
its structure can be seen in this surface rendering of the inside of the eyeball.
Exterior surface rendering and information about the quail chick data.
Information and volume data of human (me).
Tarsier and human vision hardware
Comparison of tarsier and human brain and eye, scaled so the slice brain widths are about equal.
Tarsier brain photo scanned from:
UNTERSUCHUNGEN AN TARSIUS
I. MORPHOLOGIE DES SCHWANZES NEBST ETHOLOGISCHEN BEMERKUNGEN
Heinrich Sprankel
Folia Primatol/ 1965;3:153-188 (DOI: 10.1159/000155027)
The furry human is myself.
There is some debate as to whether tarsiers are more
related to simians (like us), lemurs, or are older than both. This paper
suggests that tarsiers evolved from a very early primate ancestor,
because "the more superficial layer of the dLGN receives projections
from the
ipsilateral eye, a unique situation among the members of the Order
Primates".
Four Knot 1
A 2-D Thue-Morse pattern where the symbols are
replaced by a motif that visually connects all adjacent symbols. The
result is a woven pattern, with each "strand" forming a simple closed
loop. Only the motif was constructed and rendered with Space Software.

The two square motifs, side-by-side, where each motif is a pi/2 rotation of the other.

The recursive replacement system that results in the 2-D Thue-Morse pattern.
|
Oblique viewpoint rendering of the 3-D motif used to construct Thue-Morse chain images. (Stereo pair, cross-view.)
Constructed and rendered using a single chiral spline segment,
rotated/mirrored four times. (Credit to Greg Scott for writing the
spline code.)
curveA_b_4.vol.gz (2 MB) |

The Thue-Morse tiling. |

The pattern after a pi/4 rotation and coloring of connected
elements -- only those elements that are closed on this portion of the
potentially infinite tiling.
|
Matlab command (for the Thue-Morse tiling of this motif pair):
Why this works (nested circuits in this weave
pattern, colored by connectivity in the left image) is a mystery
to me. How would a larger Thue-Morse pattern with the same motifs be
connected? I designed the motif, shading and coloring, but I didn't
design the pattern; I found it.
Virion structure
The virion of P22, a bacteriophage. A virion is the infectious form of
a virus as it exists outside the host cell, consisting of a nucleic
acid core, and a protein coat.
Rendered from a volumetric Cryo-EM (electon microscope) asymmetric reconstruction.
"The large bulb is the head capsid, containing the DNA injected into
the host bacterium, which then commandeers the host cell, turning it
into a virus factory. The symmetry of all head capsids of various
bacteriophage is icosohedral, made up of large proteins woven together
rather like a quilt.
In some cases, the icosohedral symmetry is a little twisted, with
hexagonal units wrapped around edges instead of meeting at edges. The
corners of the icosohedron are always pentagonal." Steve McQuinn
J.Chang, P.Weigele, J.King, W.Chiu, W.Jiang:
Cryo-EM asymmetric reconstruction of bacteriophage P22 reveals organization of its DNA packaging and infecting machinery. Structure (2006) 14, pp. 1073-1082 [PubMed entry 16730179]
Abstract: "The mechanisms by which most double-stranded DNA viruses
package and release their genomic DNA are not fully understood. Single
particle cryo-electron microscopy and asymmetric 3D reconstruction
reveal the organization of the complete bacteriophage P22 virion,
including the protein channel through which DNA is first packaged and
later ejected. This channel is formed by a dodecamer of portal proteins
and sealed by a tail hub consisting of two stacked barrels capped by a
protein needle. Six trimeric tailspikes attached around this tail hub
are kinked, suggesting a functional hinge that may be used to trigger
DNA release. Inside the capsid, the portal's central channel is plugged
by densities interpreted as pilot/injection proteins. A short rod-like
density near these proteins may be the terminal segment of the dsDNA
genome. The coaxially packed DNA genome is encapsidated by the
icosahedral shell. This complete structure unifies various biochemical,
genetic, and crystallographic data of its components from the past
several decades."
3-D spiral tiles
A 3-D tiling based on a logarithmic spiral. See Logarithmic spirals, waves, and tilings for spiral Matlab code and related logarithmic spirals, images and animations.
Mouse embryo
Mouse embryo, volume rendered from MRI data. Embryonic age is 23 days after conception.
Also see animated rotation.
Raw volume data available from Caltech Atlas of Mouse Development (data © California Institute of Technology, Pasadena).
Oak cubes
Various arrangements of a volume rendered cube from
high resolution CT of a chunk of oak. Also see more (similar) patterns
at Oak cubes and hexagonal tilings and Ambiguous Triple Cube animations.
Knot a trefoil
Three
mutally linked and mutually orthogonal tori.
This is not an
image of a
trefoil knot. See tritorus_ortho_80_20_rotation.avi
(3.5 MB) and tritorus_ortho_80_20_slices.avi
(4 MB) for other viewpoints.
Human brain, Brodmann areas
A human brain volume rendered from T1 weighted MRI, an average of 27 scans (Colin27, Montreal Neurological Institute) and its conjunction with Brodmann areas (colored, at right). Stereo pairs, different combinations of same renderings.
neurons_43a_sh.jpg
Schematic set of neurons (crossed stereo pair).
bcolin24_chips.jpg
Filtered depth map of colin24 brain.
Tetra_5_oversampled8x.jpg
A fifth order Sierpinski tetrahedron. The Matlab function that generated the volume that
this image is rendered from is
cubic_manifold_general.m, hardcoded for this particular "fractal sponge".
dow_MRI_big_head.jpg
High resolution surface rendering of T1 weighted MRI of head.
Brodmann_brain.jpg
Rendered brain color coded by Brodmann area.
Huttenlocher_composite.jpg
Chart showing synaptic (density) development in three brain regions,
after Huttenlocher.
Axial MRI head slices, variety of image contrasts
Axial MRI image of the same human head, at about the same plane, with five different contrasts.
095_multi_modal_axial.jpg
The left pair used a T1 contrast MRI sequence designed to optimized
contrast between white and gray matter. The two differ in suppression
of the fat signal, most noticeable in the subcutaneous tissue on the
outside of the skull. The third and fourth used T2 contrast. The third
is a gradient echo-planar (EPI) image, with a T2 contrast sequence used
in functional imaging due to it's sensitivity to the T2* component;
blood oxygenation differences result in T2* variations through time.
Visisble Woman head, rendered
Volume rendering of the Visible Woman's head.
Segmentation_flow_1.jpg
periph_act.jpg
owl_T2_sag.jpg
t
gasket.jpg
A Menger sponge rendering.
cubic_cross_1_copy_rendered.jpg
CT_head_skin_threshold_axial_2.jpg
CT_head_skin_threshold.jpg
bJC_T1_smooth_white_oblique.jpg
bJC_T1_smooth_white.jpg
Age_range_composite.jpg .7MB
000001_LR_render_1.jpg
000001_LR_ortho_slice_1.jpg
000001_LR_FFG_composite.jpg
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Comments are welcome (dow[at]uoregon.edu).