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Observers were presented with various types of stimulus expansion and contraction which resulted in marked misperceptions of size. Firstly, the perceived size of an object which is changing in size is shown to be biased in the direction of the size change. Secondly, expansion or contraction of the internal texture of objects is found to influence their perceived size. Finally, an illusory texture manipulation in the form of a movement after-effect is shown to produce the same type of size misperception as a real expansion or contraction of internal texture. The spatio-temporal characteristics of these illusory size changes are investigated.

Jumbo and medium sized summer onions (Allium cepa) of three cultivars were stored at 1, 4, 21°C for 6 months. Medium yellow onions held best at 1°C; jumbo sizes showed lowest losses at 4 and 21°C. Highest losses occurred in white onions. Major losses were due to decay. Sprouting occurred after 3 months at 4°C; none was observed at 1°C. Pungency increased and sugar decreased at 4 and 21°C; onions remained dormant at 1°C. Changes in quality parameters were factors of size and cultivar and may influence sprouting and decay over storage. Weight loss was an index to onion size change. Sprouting increased on reconditioning onions. Medium yellow Grano onions stored best on transfer to higher temperatures.

Three pigeons were trained on the matching-to-sample task with 12-mm form stimuli (a circle, a triangle, and a cross). After 105 acquisition sessions, the form stimuli were reduced in size to 8 mm for 65 sessions and then to 5 mm for 80 sessions. During the next phase, the samples were 12 mm in size and the comparison stimuli were 8-mm forms, or vice versa, 8-mm samples and 12-mm comparison stimuli. Finally, the samples and comparison stimuli were presented as growing (increasing from 5 to 12 mm) or shrinking (decreasing from 12 to 5 mm) forms. The birds learned to match the three different sizes of forms and matched well even when the sample and comparison stimuli were not the same size. They could not match samples only on the basis of direction of size change.

This paper provides details on the Advanced Photovoltaic Solar Array (APSA) wing design, fabrication, and testing. The impact of array size change on performance and mechanical characteristics is discussed. Projections for future performance enhancements that may be expected through the use of advanced solar cells presently under development are examined.

The qualitative and quantitative characteristics of rotation, contraction, and motion-in-depth motion aftereffects (MAEs) produced by rotating Archimedes spirals were compared for spirals differing in arm length (90°, 270°, and 720°). There were three test stimuli. The spokes and rings test stimuli were figures whose contours were orthogonal to the direction of motion of the MAEs produced by the rotational and radial components of the spiral’s motion, respectively. The floating disk test stimulus was used to test for a motion-in-depth MAE. In Experiment 1, naive subjects viewed the spirals for 30 sec and 3 min. The MAE components reported corresponded to the rotational and radial components of motion in the proximal stimulus. In Experiment 2, experienced subjects were used to measure decay time constants (DTCs) after 15 min of adaptation. The rotation MAE had a DTC that was shorter than the other two DTCs. Results support the hypothesis that the complex stimulus produced by rotating Archimedes spirals is resolved into rotational and radial components by structures in the visual system that are specifically sensitive to rotational and size-change relative motion patterns (Regan, 1986). They also support Hershenson’s (1982) suggestion that the spiral aftereffect is produced by the same perceptual structures that mediate the perception of rigid object motion in depth.

WHILE watching noise displayed on a television screen recently I noticed a visual effect which I report here. As normally viewed, displays of video noise (‘snow’) have the appearance of fields of small speckles which seem to dart about at random. When, however, the noise is viewed monocularly, the texture of the field seems finer and the speckles more nearly static. The display seen monocularly has the appearance of a field of smaller speckles which scintillate in situ. I have shown the effect to about ten friends and colleagues, without telling them what to expect. All noticed some difference between binocular and monocular viewing and several promptly described exactly what I had seen. In general, the size change was more consistently reported than the motion change.

Meglumine iothalamate (280 ml I/ml) and sodium iothalamate (400 mg I/ml) in doses of 700 mg I/kg bw, were injected i.v. as a bolus in dogs. Renal size, urine flow rate, arterial pressure, renal blood flow and mean transit time and renal blood volume were measured before and after injection. All changes were qualitatively and quantitatively identical for both drugs. They produced a small transient renal shrinkage followed by a greater and prolonged renal enlargement. During the period of renal enlargement, urine flow increased. The time course of the enlargement paralleled the increase of urine flow rate. Renal blood flow also increased but both the mean transit time and renal vascular volume decreased. Therefore, the kidney size increase after i.v. injection of large doses of urographic contrast media cannot be attributed to an increased volume of the vessels. Most likely it is caused by diuresis-induced increase in the volume of the tubules.

Proteoglycan subunit isolated from the growth cartilage of rachitic chicks is of much smaller size than the corresponding preparation from vitamin D-treated chicks. The size change can be related to differences in plasma calcium concentration and not to the vitamin D status of the chicks.

This paper presents the first in a series of increasingly complex models of naticid gastropod predator-prey coevolution. This model is restricted to one predator and one prey and to coevolutionary feedback in size change. Subsequent models will involve multiple species and evolving morphologies. Gastropods of the family Naticidae are predators on other molluscs, both gastropods and bivalves, which they attack by drilling through the shells of their prey. The unique characteristics of the naticid gastropod system for testing aspects of coevolutionary theory in the fossil record were discussed by Kitchell et al. (1981) and Kitchell (1982).

The following two aftereffects resulted from inspecting a square whose vertical edges moved towards each other with a ramping waveform: (1) a static test square appeared to be continously expanding along the horizontal direction, and (2) a static test square appeared to be moving in depth. We quantified each aftereffect by measuring the real rate of size change required to cancel it. Both aftereffects decayed exponentially. No. 1 rapidly with a time constant between 6.4 and 9.9 sec. and No. 2 more slowly with a time constant between 21 and 54 sec. Because of the different decay rates, the two aftereffects could be seen separately. We propose that the existence of these two aftereffects is consistent with a psychophysical model in which unidirectional motion filters feed a changing-size filter that in turn feeds a motion-in-depth stage. We tentatively suggest that this model might help to explain how the visual system resolves the ambiguity of a retinal image whose magnification is changing.

Injection of 5 mug endotoxin to adult C57BL mice caused a marked increase in the sedimentation velocity of granulocytic and macrophage progenitor (colony-forming) cells in the bone marrow. This change was maximal two days after injection and was not accompanied by corresponding changes in total marrow nucleated cell populations. The endotoxin-induced shift was not dependent on the presence of the thymus but did not occur in mice challenged after preinjection with endotoxin. No changes in buoyant density, cell cycle status, pattern of differentiation and responsiveness of granulocytic and macrophage progenitor cells were observed after the injection of endotoxin. The increased sedimentation velocity of progenitor cells appears to indicate an increase in cell volume but the mechanisms involved have not been identified.

Circular samples of commonly used liners were prepared and immersed in solutions of nine cleansers. Solutions were changed daily for a period of 1 month. Six properties were tested: color change, porosity, surface distortion, size change, water sorption, and solubility. Statistical analysis was applied to measurements to evaluate performance of both cleansers and liners. The results demonstrate that selection of a liner cannot be based on a single property. Changes in resiliency of the liners were not tested in this experiment, but it is recognized that this could be an important factor in liner selection. The liners found to be least affected by the cleansers were Lynal, Tissuedyne, F.I.T.T., and Hydro-Cast, in that order. Viscogel, Softone, and Veltec were most affected. Clorox/Calgon and Miller demonstrated the same overall average performance, tying for first place for four of the liners. Clorox/Calgon was compatible with most liners (six of eight). Mersene and Duo tied for third and fourth places. The thickness of liner materials made little difference on the effects of the cleansers on the properties evaluated.

As an object approaches the eye, its retinal image size grows larger and its surface texture appears to grow coarser. We compare these two visual correlates of motion in their effectiveness as stimuli for motion in depth. In some experiments texture and object size both expanded or both contracted: in other experiments the two stimuli were pitted against each other. When texture and size change as for a rigid, nonrotating real world object an untextured square can be a more effective stimulus for motion in depth than the same square with texture. On way of describing this finding is to calculate the departure from linear summation of texture and size contributions. The departure is greatest when texture is static, being even greater than when texture changes in the opposite direction to size.

The growth of Tetrahymena pyriformis at three different incubation temperatures, 10 °, 20 ° and 30 °C, results in three classes of cell size having average volumes of 16,250 μ3, 12,350 μ3, and 9375 μ3 respectively. The frequency distributions of each class were determined, and they indicate that the differences in the averages are not merely the result of weighting the distribution with any one cell volume since there is a shift in the entire range of the volume distributions. The QO2 (106 cells) were also measured. The larger cells have the higher rate of oxygen consumption when measured at 20 °C, having QO2 (106 cells) of 66, 38 and 23 respectively. The surface to volume ratios were determined as this ratio was considered to be one factor which may govern the change in cell size with temperature. The ratios tend to remain constant. The size change cannot be entirely attributed to surface-dependent metabolism.

The seasonal emergence of Culicoides furens (Poey) has been studied for about 15 months. Three presently important habitats of this species, namely tidal ditches, brackish pools, and impoundments, were observed for comparison. The pattern of emergence from impoundments differed from the other 2 habitats in that relatively few adults were produced early in the year with the onset of warmer weather (March to June), but the rate of emergence continued at a higher level into the beginning of the “winter” months and was generally higher throughout the cold period (September to March). Tidal ditches and brackish pools yielded most adults early in the year, with numbers generally diminishing through the summer and falling sharply to a low level throughout the cold period. The emergence patterns are interpreted in terms of the number of generations completed annually and in light of other data concerning seasonal size change and potential for autogenous development of eggs. Data obtained concurrently with the main study indicated that light traps may provide incomplete information about the seasonal emergence of C. furens .

The computer representation of the medical image is the image matrix, where the gray levels corresponding to the element with the coordinates x, y create a more or less complex surface whose shape is far from smooth [4]. The study presents a study of homogeneous liver structures of MRI images using two fractal image analysis methods and the determination of those that are insensitive to the size change of the area of interest.

Regimes of cladogenetic change in body size recognized in the fossil record are related to the time scales over which they are observed. A new categorization of regimes of cladogenetic size change is proposed: this scheme includes seventeen types. In a random distribution, the pure, single‐cause regimes are rare (0.01 probability of appearance) while mixed regimes, resulting from the simultaneous operation of two or more causes are frequent (0.115 probability of appearance). Some regimes seem to be nonrandomly distributed.

Several studies in humans and non-human primates have shown that tool-use can expand near peripersonal space (Farne & Ladavas, 2000; Iriki, Tanaka, & Iwamura, 1996). In humans, the extension of the near peripersonal space is revealed by an increase in the severity of cross-modal extinction caused by visual stimulation at the distal edge of a rake after its use as a reaching tool. The crucial question addressed here concerns whether the dynamic re-sizing of the peri-hand space in humans constitutes a real spatial expansion of visual-tactile peri-hand area along the tool axis. Alternatively, it could constitute a shift of the integrative area from the hand towards the distal edge of the tool, or the formation of a novel visual-tactile integrative area at the same distal location (Holmes, Calvert, & Spence, 2004). We contrasted the alternative predictions made by these hypotheses in a group of RBD patients by probing, at different locations along the tool axis, the changes induced by tool-use on cross-modal extinction. By assessing the visual-tactile extinction near the hand, midway along the tool, and at the distal edge of the tool we found an increase in visual-tactile extinction after tool-use both at the middle and the distal location along the tool axis. In contrast, no change intervened at the hand proximity. These findings support the view that the tool-use dependent re-mapping of peri-hand space in humans consists of a continuous elongation of visual-tactile peri-hand area from the hand towards the tip of the tool.

We present a study of the dynamics of protein aggregation using a Bloch surface wave (BSW) label-free sensing scheme. In a previous work, we demonstrated the ability to detect the early dynamic events of fibrillogenesis of amyloid beta-peptides (A beta), linked to Alzheimer's Disease. Here, we demonstrate the efficacy of the BSW sensor by describing a simultaneous light scattering measurement, with the purpose of real-time monitoring the size change of the A beta aggregates, throughout fibrillization.

The growth of the vertebrate skull and brain is usually unidirectional and more or less stops when animals are adult. Red-toothed shrews break this rule. They seasonally shrink and regrow brain and skull size by 20% or more, presumably to save energy when conditions are harsh. The size change is anticipatory of environmental change and occurs in all individuals, but it is unknown whether its extent can be modulated by environmental conditions. We kept shrews under different conditions, monitored seasonal changes in skull size with series of X-rays, and compared them with free ranging animals. We found extensive differences in the pattern of skull size change between experimental groups. Skull size of shrews kept at constant temperature showed a steady decline, while the skull size changes of free ranging shrews and captive individuals exposed to natural temperature regimes were identical. In contrast, body mass never reached the spring values of free ranging shrews in either captive regime. The extent of this adaptive seasonal pattern can thus be flexibly adapted to current environmental conditions. Combining reversible size changes with such strong phenotypic plasticity may allow these small, non-hibernating predators with high metabolic rates to continue being successful in today’s changing environments.

The stride frequency at which animals of different size change from one gait to another (walk, trot, gallop) changes in a regular manner with body mass. The speed at the transition from trot to gallop can be used as an equivalent speed for comparing animals of different size. This transition point occurs at lower speeds and higher stride frequencies in smaller animals. Plotting stride frequency at the trot-gallop transition point as a function of body mass in logarithmic coordinates yields a straight line.

Unfertilized Arbacia eggs have five electrophoretically distinct malic dehydrogenases which differ in their rates with pyridine nucleotide analogs. Both the number of peaks and their relative size change during early embryonic development. A D-malic dehydrogenase which utilizes the 3-acetylpyridine analog of DPN but not DPN itself was found. Electrophoresis on starch gel results in five peaks, all of which differ from the peaks of the L-malic dehydrogenases.

Recent studies have investigated the effect of an irrelevant size change on reaction time in tasks involving comparison of same or different shapes. In most cases, however, studies have examined simultaneous presentation or else successive presentation where the second stimulus was always larger than the first. In the present study, subjects made same-different shape judgments on successively presented closed geometric forms, where the second form was smaller than, larger than, or the same size as the first. Comparison reaction times were observed to increase with increasing size difference regardless of the direction of size change (i.e., when the second figure was either larger or smaller than the first). In addition, the effects of size change were identical for both "same" and "different" responses. These findings were seen to support an analog normalization process in which subjects mentally equate the figures for size before comparing their shapes. The relation of these results to previous data is discussed.

Some theoretical guidelines, 286. — Evidence: fertility and sex composition, 289. — Would family size change if sex of children were controlled? 297. — Variation in the probability for a boy and the aggregate sex ratio, 299. — Summary, 302. — Appendix, 302.