Effects Of Changes In Size Research Articles

The effects of climate and population on human land use patterns in Europe from 22ka to 9ka ago

Between 22ka and 9ka ago, after the Last Glacial Maximum (LGM) and during the transition to the Holocene, mobile hunter-gatherer populations, differentiated by their stone tool assemblages, periodically dispersed and contracted across Europe. It is well understood that climate played an important role in human distributions and population sizes during the post-LGM Late Pleistocene and Early Holocene, but the question remains as to whether increasing population sizes drove early human dispersal. Here, using a spatiotemporal species distribution model to infer the fundamental and potential human climatic niche space of Late Upper Paleolithic, Final Paleolithic and Early Mesolithic Europe, and hypotheses derived from the Ideal Distribution Model, we test i) how changes in climate affected the size and extent of the projected potential human niche space, ii) for effects of changes in size of projected potential niche on regional human population sizes, iii) whether increasing human population sizes drove human dispersal into less climatically suitable habitats, and iv) whether populations associated with different high-order material culture groupings (macro-level technocomplexes) occupied different climatic spaces. We find that changes in climate correlate strongly with the size and extent of the projected potential human niche space, that increases in the projected human niche space correlate with increases in human population, that human population size is just beginning to become large enough to influence land use and dispersal patterns at the Pleistocene-Holocene transition, and that archaeological technocultural entities overlap in their fundamental climatic niche space. This overlap implies that changing tools forms cannot readily been seen as reflecting adaptations to changing climates.

Effect of Size Change on Mechanical Properties of Monolayer Arsenene

Effect of Size Change on Mechanical Properties of Monolayer Arsenene

The impact of size, composition and duration of the central bank balance sheet on inflation expectations and market prices

We analyse the effects of announcements of changes in the Eurosystem’s balance sheet size, duration and composition on inflation expectations, the exchange rate, the 10-year euro area government bond yield and stock returns, using local projections. We explicitly take into account interaction effects between the three balance sheet dimensions. We provide evidence for the duration extraction channel of monetary policy transmission as we find that the bond yield is sensitive to the combined impact of shocks to balance sheet size and duration. The exchange rate is also affected by a joint size-duration shock. Moreover, the bond yield and exchange rate are sensitive to the joint effect of changes in size and composition. The results indicate that interactions between balance sheet dimensions matter.

The Impact of Size, Composition and Duration of the Central Bank Balance Sheet on Inflation Expectations and Market Prices

We analyse the effects of announcements of changes in the Eurosystem’s balance sheet size, duration and composition on inflation expectations, the exchange rate and the 10-year euro area government bond yield, using local projections. We explicitly take into account interaction effects between the three balance sheet dimensions. We provide evidence for the duration extraction channel of monetary policy transmission, as we find that the bond yield is sensitive to the combined impact of shocks to balance sheet size and duration. The exchange rate is also affected by a joint size-duration shock. Moreover, the bond yield and exchange rate are sensitive to the joint effect of changes in size and composition. The results indicate that interactions between balance sheet dimensions matter.

Effects of filtration-induced size change on the subsequent transport and fate of graphene oxide in saturated porous media

A particle size change occurs ubiquitously during transport of nanoparticles in the subsurface and is likely to influence nanoparticle fate and transport behaviours. The effects of this size change on the subsequent transport of eluted graphene oxide (GO) in saturated media were therefore investigated under various ionic strength (IS) and filtration degree conditions. Aggregation kinetics revealed that size change after filtration only occurred at relatively high IS conditions. As the filtration column length increased from 15 cm to 30 cm, sizes of aggregates in filtrates for large-sized and small-sized GO populations decreased and increased, respectively, and both approached to their steady aggregate sizes. Aggregation, straining, sedimentation, bridging, DLVO interactions, or a combination of these mechanisms were involved in the size change process during filtration. After passing through the 30 cm filtration column, filtered GO, in comparison with original GO, exhibited stronger mobility than expected, suggesting neglecting size change will result in underestimation of the nanoparticle mobility in porous media.

Allocation to clonal and sexual reproduction and its plasticity in Vallisneria spinulosa along a water‐depth gradient

AbstractVariations in water level profoundly affect functional stability of freshwater ecosystems, as well as macrophyte growth and reproduction. Although the trade‐off between allocation to clonal and sexual reproduction in clonal plants can be influenced by a variety of environmental factors, whether variations of reproductive allocation (RA) in response to different environments are driven only by a size‐dependent effect (apparent plasticity) or whether RA can also change independently of plant size (true plasticity) is uncertain. We conducted an experiment in nine outdoor mesocosms (6400 L) to investigate the response of clonal and sexual reproduction and vegetative growth of a perennial submerged macrophyte Vallisneria spinulosa at water depths of 50, 100, or 150 cm. We evaluated size‐dependent and size‐independent effects of water depth on sexual and clonal RA. Deep water reduced vegetative size and sexual output (mass of fruits produced), but increased tuber production of V. spinulosa. There was an apparent trade‐off between reproductive modes in terms of biomass investment; plants in deep water allocated more resources into clonal propagation and reduced investment in sexual reproduction compared to plants in shallow or intermediate water. Slopes of allometric relationships (sexual vs. vegetative biomass and clonal vs. vegetative biomass) were significantly affected by water depth. Shifts in sexual RA in response to varying water depths were largely size‐dependent, but there were also size‐independent effects. In contrast, size‐independent effects were more important than effects of size changes in determining clonal RA. We concluded that V. spinulosa adapted to a water‐depth gradient by plastic trade‐offs between clonal propagation and sexual reproduction. Furthermore, a size‐independent effect on RA suggests a flexible reproductive strategy that could be critical for plant performance in changing aquatic environments.

Immigration-induced effects of changes in size and skill distribution of the labor force on wages in the U.S.

We isolate the effect of immigration-induced changes in the size and skill distribution of the labor force on labor market outcomes using a model in which firms endogenously respond to these changes. We analytically show that while the immigration-induced increase in the size increases the relative wages, employment and output shares of the skill intensive sector, changes in the skill distribution lead to analytically ambiguous effects. We derive quantitative results for the US economy under different counter-factual scenarios with respect to immigration-induced changes in size and skill distribution of the labor force, where these changes resemble those of U.S. as a whole, New York, California and Canada, and reflect different immigration policy regimes. For example, immigration increases the mass of workers at the lower range of the skill distribution in the U.S., and the upper range in Canada. Regardless of these differences across scenarios, our quantitative results indicate that immigration increases the relative average wages of the skill intensive sector. Further, real wages of all workers increase due to reduced prices caused by the increased size of the labor force.

HYDRODYNAMIC REGIME AND WATER EXCHANGE IN NAI LAGOON, NINH THUAN PROVINCE

This study presents the researching results of the characteristics of hydrodynamic regime and the water exchange in Nai lagoon in Ninh Thuan province and the impact of change in embankment system according to simulation by using numerical models. By application of 3-dimensional MIKE 3 model, the pattern has been established to verify the data of water levels. Calculation is set up in July and in October (representing wet and dry seasons in the region). The simulation results show that in October tidal amplitude is greater than that in July. The flow rate in the center of the lagoon is small, an average of about 2 cm/s, the largest not exceeded 4 cm/s. Regime of water exchange between Nai lagoon and the sea is differences in the rainy and dry seasons. The effect of changes in size of embankment system on hydrodynamic regimes and water exchange of Nai lagoon is also analyzed, evaluated.

被写体サイズの変化によるコンテンツおよび被写体の主観評価に対する影響の考察

被写体サイズの変化によるコンテンツおよび被写体の主観評価に対する影響の考察

Changes in Angular Size and Speed Affect the Judged Height of Objects Moving over a Ground Surface

Kersten et al (1997, Perception 26 171-192) showed that the perceived path of an object moving over a ground surface can be manipulated by changing the path of a shadow. Using a scene similar to Kersten's "ball-in-a-box" scene, we investigated the effect of angular size and angular speed in determining the perceived height of a moving sphere when optical contact (the position at which the object contacted the ground in the image) indicated that the sphere was receding in depth. In four experiments we examined both the effects of changes in size and speed, and the effects of constant levels of size and speed. Increases in angular size or speed during a motion sequence resulted in judgments of increased height above the ground plane. The angular size at the end of the motion sequence was also important in determining judged height, with greater height judged with larger final sizes.

Effects of changes in size, speed, and distance on the perception of curved 3-D trajectories

Previous research on the perception of 3-D object motion has considered time to collision, time to passage, collision detection, and judgments of speed and direction of motion but has not directly studied the perception of the overall shape of the motion path. We examined the perception of the magnitude of curvature and sign of curvature of the motion path for objects moving at eye level in a horizontal plane parallel to the line of sight. We considered two sources of information for the perception of motion trajectories: changes in angular size and changes in angular speed. Three experiments examined judgments of relative curvature for objects moving at different distances. At the closest distance studied, accuracy was high with size information alone but near chance with speed information alone. At the greatest distance, accuracy with size information alone decreased sharply, but accuracy for displays with both size and speed information remained high. We found similar results in two experiments with judgments of sign of curvature. Accuracy was higher for displays with both size and speed information than with size information alone, even when the speed information was based on parallel projections and was not informative about sign of curvature. For both magnitude of curvature and sign of curvature judgments, information indicating that the trajectory was curved increased accuracy, even when this information was not directly relevant to the required judgment.

Effect of Size Change and Brightness Change of Visual Stimuli on Loudness Perception and Pitch Perception of Auditory Stimuli

Effect of Size Change and Brightness Change of Visual Stimuli on Loudness Perception and Pitch Perception of Auditory Stimuli

Size-Sensitive Perceptual Representations Underlie Visual and Haptic Object Recognition

A variety of similarities between visual and haptic object recognition suggests that the two modalities may share common representations. However, it is unclear whether such common representations preserve low-level perceptual features or whether transfer between vision and haptics is mediated by high-level, abstract representations. Two experiments used a sequential shape-matching task to examine the effects of size changes on unimodal and crossmodal visual and haptic object recognition. Participants felt or saw 3D plastic models of familiar objects. The two objects presented on a trial were either the same size or different sizes and were the same shape or different but similar shapes. Participants were told to ignore size changes and to match on shape alone. In Experiment 1, size changes on same-shape trials impaired performance similarly for both visual-to-visual and haptic-to-haptic shape matching. In Experiment 2, size changes impaired performance on both visual-to-haptic and haptic-to-visual shape matching and there was no interaction between the cost of size changes and direction of transfer. Together the unimodal and crossmodal matching results suggest that the same, size-specific perceptual representations underlie both visual and haptic object recognition, and indicate that crossmodal memory for objects must be at least partly based on common perceptual representations.

The effects of size changes on haptic object recognition

Two experiments examined the effects of size changes on haptic object recognition. In Experiment 1, participants named one of three exemplars (a standard-size-and-shape, different-size, or different-shape exemplar) of 36 categories of real, familiar objects. They then performed an old/new recognition task on the basis of object identity for the standard exemplars of all 36 objects. Half of the participants performed both blocks visually; the other half performed both blocks haptically. The participants were able to efficiently name unusually sized objects haptically, consistent with previous findings of good recognition of small-scale models of stimuli (Lawson, in press). However, performance was impaired for both visual and haptic old/new recognition when objects changed size or shape between blocks. In Experiment 2, participants performed a short-term haptic shape-matching task using 3-D plastic models of familiar objects, and as in Experiment 1, a cost emerged for ignoring the irrelevant size change. Like its visual counterpart, haptic object recognition incurs a significant but modest cost for generalizing across size changes.

Effects of Size Congruency on Item and Size Recognition with Words or Pictures

The effect of size changes (8:1 or 1:8) between learning and recognition sessions upon item and size recognition was tested, using either pictures or words as stimuli. Participants (N = 34) viewed color photographs of everyday objects or the corresponding printed words and then performed 160 trials of a recognition task, including 50% new stimuli, for which they had to indicate whether each item had been seen before and whether its size had changed. Item recognition, for pictures only, was improved by size congruency between the learning and test sessions. In contrast, size recognition was raised by learning/test-size congruency for both pictures and words. Both word- and picture-learning stimuli produced higher item and size recognition when large in area rather than small. The data are interpreted as showing the stronger role of spatial coding with pictorial than with verbal stimuli.

The interaction between size and accommodation cues in predicting proximity

Purpose: We have shown previously that proximal stimulation using size change can enhance or degrade accommodation step responses in open and closed loop conditions. The aim of the current experiment is to determine the relationship between the perceptual response to proximal stimulation based on size change and blur change for a range of target vergences.Methods: Perceptual thresholds for pure blur change, pure size change, coherent blur and size change and conflicting blur and size change were measured monocularly in 12 visually normal subjects (mean refractive error of ‐0.79D ± 2.41D and mean age 25.17 years ±3.10 years) using a 2‐alternative forced‐choice technique with 20 presentations per condition. Threshold estimates were obtained from psychometric functions using the bootstrap method. All subjects were fully corrected and had normal amplitudes of accommodation for their age. Threshold for proximal perception to blur only stimulation was established using target vergence changes of 0, 1, 2 and 3D. The effect of size change was then assessed at the same four levels of blur change. Stimuli were presented randomly with the position of the near and far vergences also randomised. This was repeated under four conditions: (1) Blur only. (2) Size only. (3) Size change coherent with the vergence change. (4) Size change conflicting with the vergence change.Targets consisted of pairs of photographic slides that contained strong monocular size and depth cues which were viewed successively in a 4D Badal lens system. On each trial the subjects compared the perceived proximity of the targets.Results: Considerable individual variation was found in the subject's perceptual responses to the four experimental conditions presented. The responses of all subjects were predicted by one of the following rules: (1) No effect of size. (2) Blur and size interact constructively. (3) No effect of blur. (4) Blur elicits a proximal response but size is used to determine the direction of the proximal effect.Without any size cue, eight subjects (66%) identified the direction of the vergence change correctly while the remaining subjects consistently perceived the target with lower dioptric vergence to be closer. The threshold required to accurately determine proximity from blur only cues was 2.27D ± 0.31D. In the absence of blur, size cues induced a proximal effect in 33% (n = 4) subjects. The combination of size and blur cues produced a variety of response patterns, some subjects’ responses were dominated by blur cues while others relied heavily on size stimulation.Conclusions: Our ability to perceive a target as close can be dependent upon either size and/or accommodation signals. Interactions between the stimuli of dioptric target vergence and target size were found to be additive for producing a perceived proximity response.

Tidal Barrages and Birds

This paper reviews the main effects that building tidal power barrages would have on the bird populations using Britain's estuaries. The changes in the tidal prism that would occur after a tidal power barrage is built are discussed in the context of their effect on the ecology of the estuary. Three main issues are discussed; the effect of changes in size and nature of the intertidal areas of the estuary, effects on saltmarshes, and the displacement of birds at closure. Recently, tidal stream technologies have been developed which are individually likely to have small effects on birds. However the cumulative effects of large scale tidal stream arrays need to be investigated. Finally, the effects of tidal barrages are put in the context of Britain's energy policy and the need to reduce greenhouse gas emissions. Should tidal power barrages be considered in the future, there will be a need for strategic assessments to be used to select sites that maximize the energy produced while minimizing the impacts on bird populations.

Effect of changes in size and index of refraction on the resonance wavelength of microspheres

Wave theory and geometrical optics are used to investigate the effect of small changes in size and index of refraction on the resonance wavelength of spherical microresonators. It is shown that changes in the index of refraction have two effects: These changes affect the phase jump on the surface and the optical path length in the resonator. Under certain conditions the effect of the external or internal index of refraction becomes negligible. The influence of the order number of the resonance modes is investigated. Finally, the results of the theoretical analyses are applied to calculate the effect of temperature on the resonance wavelength.

ALLOMETRIC SCALING OF PHYSICAL PERFORMANCE IN CHILDREN AND YOUTH FROM MAPUTO, MOZAMBIQUE

1597 The purpose of this study was to analyse the power of allometric scaling in the interpretation of physical performance in children and youth from Mozambique. Sample size comprises 317 girls and 276 boys between the ages of 8 to 15 from the capital city, Maputo. Height, weight, sit-up's (number in 60s), hand grip, agility run, and one mile run were recorded. The analysis was done according to the well-known power function formulae: Y=aXb, where Y is the performance variable, X is height or weight, a is a constant multiplier, and b is the empirical dimensional exponent. Empirical b values were compared to theoretical expectations. All analysis were done in SYSTAT 7.0. For hand grip the exponents were greater than expected (boys: height3.84; weight1.17; girls: height3.86; weight1.21); in agility run the b values were not significantly different from zero; empirical b values for the mile run (boy: height1.46; girls: height1.88) and sit-up's (boys: height2.08; girls: height1.20). Weight exponents for sit-up and mile run were not significantly different from zero. In conclusion we have to point out the importance of considering the fact that physical performance is affected by differences in size and that scaling is a procedure to adjust for such differences in children and youth of both gender. Major findings suggest that: (1) empirical b values were greater than theoretical expectations; (2) physical performance increased more rapidly than did body size; (3) exception was made for agility run, and probably some weight independent performance (sit-up and mile run) due to the absence of excess weight and body fat in boys and girls; (4) the effect of size changes in physical performance is somehow dependent of gender; (5) and it is open to debate the idea of a constant shape as growth occurs, since in this study the b value relating weight to height was 2.89.

Visual and tactile memory for 2-D patterns: Effects of changes in size and left-right orientation

Visual identification of 3-D objects depends on representations that are invariant across changes in size and left-right orientation. We examined whether this finding reflects the unique demands of processing 3-D objects, or whether it generalizes to 2-D patterns and to the tactile modality. Our findings suggest that object representation for identification is influenced greatly by the processing demands of stimulus materials (e.g., 2-D vs. 3-D objects) and stimulus modality (touch vs. vision). Identification of 2-D patterns in vision is adversely affected by left-right orientation changes, but not size changes. Identification of the same patterns in touch is adversely affected by both changes. Together, the results suggest that the unique processing demands of stimulus materials and modality shape the representation of objects in memory.