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The enhanced understanding of nanomaterials properties and processing has led to increased use of nanotechnologies, which has also led to greater scrutiny on the commercialization and acquisition of emerging nanoenabled technologies. Caused by knowledge gaps on the unique behaviors, risks, and liabilities of novel engineered nanomaterials, this caution, when not evidence based, slows production and stifles innovation. Reducing the uncertainty surrounding the environmental risks and benefits of nanoenabled technologies, including their resilience in harsh environments, will speed the development and transition of advanced material technologies. In this work, a multifaceted research program generated data and processes to reduce that environmental uncertainty. Specifically, this case study examined printed, nanoenabled environmental sensors and their components to develop toxicological data and parameterize a life-cycle assessment. The study tested the sensors’ resilience in environmental weathering studies that considered both the potential release of the ingredient nanomaterials and the performance of the sensors after exposure to several harsh environmental climates and then created life-cycle inventories to determine environmental impact and reduce cost of research and development. Finally, this case study developed software tools to mitigate the cost of research and provide a framework for presenting toxicology data.

Previous attempts to measure localization bias around a right-angle turn (L-trajectory) have found either no spatial bias off the trajectory (Whitney, Cavanagh, & Murakami, 2000) or a bias, in different experiments, both 'inside' and 'outside' the trajectory (Nieman, Sheth, & Shimojo, 2010). However, Eagleman and Sejnowski (2007) presented data showing that the perceived location of a brief feature on two moving stimuli could be predicted from the vector sum of their directions after the feature appeared. Such a vector sum with an L-trajectory could predict that the perceived position before the turn should be biased 'sideways' off the trajectory, in the direction of the final motion. With stimuli that particularly facilitated accurate vernier judgments, and measuring bias via the flash-lag illusion, this is indeed what we observed. Our data thus favour Eagleman and Sejnowski's (2007) supposition. Further, the bias occurred before the change in direction, rather than after it, supporting the contention that it is motion after a point being sampled that affects its perception (Bachmann et al., 2003; Eagleman & Sejnowski, 2007; Krekelberg & Lappe, 2000; Nieman, Sheth, & Shimojo, 2010).

The research examined relational processing following stroke. Stroke patients (14 with frontal, 30 with non-frontal lesions) and 41 matched controls completed four relational processing tasks: sentence comprehension, Latin square matrix completion, modified Dimensional Change Card Sorting, and n-back. Each task included items at two or three levels of relational complexity. Relational processing was impaired in the stroke groups. This was due mainly to items at the intermediate ternary-relational level of complexity. Less complex binary-relational items and more complex quaternary-relational items (the latter are difficult for adults generally) were less sensitive to stroke status. Impairment was greater in frontal than non-frontal stroke patients. Positive inter-correlations among measures supported the domain-general nature of relational processing. Implications for assessment and intervention are discussed.

We calculate the Newtonian gravitational potential and field of a cubic, homogeneous asteroid and we a pply it to the orbit of possible satellites. Large astronom ical objects such as stars or planets, naturally te nd to form spherical shapes due to the dominance of the gravit ational forces, but as a thought experiment, we con sider the properties of a planet in the form of a perfect cub e. We investigate the formation of stable orbits ar ound such cubic objects, for the case of a static as well as a rotating cube employing the method of Poincare sections. The calculation of the gravitational field around non-s pherical objects has a significant role in space mi ssions to investigate asteroid belt objects that require calc ulating orbits around a large non-spherical mass. T he calculation of such non-spherical fields also has r elevance in identifying deposits or beds of ores in side the Earth, by measuring gravitational anomalies.

Two flash-lag experiments were performed in which the moving object was flashed in a succession of locations creating apparent motion and the inter-stimulus distance (ISD) between those locations was varied. In the first (n=10), the size of the flash-lag illusion was a declining non-linear function of the ISD and the largest reduction in its magnitude corresponded closely to the value where observers judged the continuity of optimal apparent motion to be lost. In the second (n=11) with large ISDs, we found the largest illusions when the flash initiated the movement, and no effect was observed when the flash terminated the movement. The data support motion position biasing or temporal integration accounts of the illusion with processing predominantly based on motion after the flash.

A dual-task paradigm was used to examine the effect of withdrawing attentional and/or cognitive resources from the flash-lag judgment. The flash-lag illusion was larger, and performance in a detection task was generally poorer, under dual-task conditions than in single-task control conditions. These effects were particularly pronounced when decisions in the two tasks were required simultaneously, as compared to when they could be made sequentially. The results suggest that a time-consuming process is involved in the flash-lag decision, of such a nature that prolonging the process increases the magnitude of the illusion.

Our studies have revealed a sex-specific effect of fetal programming on sodium (Na+) excretion in adult sheep whereby the males exhibit reduced Na+ excretion and an attenuated natriuretic response to Ang-(1-7) as compared to the females. We hypothesize that the renal proximal tubules are a key target for the early programming effects of glucocorticoids exposure to regulate Na+ handling in the adult males. Therefore, we isolated and cultured cortical proximal tubule cells (RPTC) from adult male and female sheep antenatally exposed to betamethasone (Beta) or vehicle. Na+ uptake and nitric oxide (NO) were assessed with Sodium Green and DAF fluorescence prior to and following a low dose of Ang-(1-7) (1x10-11 M) in isolated RPTC from sheep at ~1.5 years of age. Data are expressed as % of basal uptake or area under the curve (AUC) for Na+ or % of control for NO. Male Beta RPTC exhibit greater Na+ uptake than male vehicle cells (427±32%, n=13, vs. 315±28%, n=14, p0.05). Ang-(1-7) inhibited Na+ uptake in RPTC from vehicle male (255±40%) and from both vehicle (191±14%) and Beta (209±11%) females (Figure 1B), but failed to attenuate Na+ uptake in Beta male cells (Figure 1A). Beta exposure also abolished NO stimulation by Ang-(1-7) in male but not female RPTC (Figure 1C). We conclude that an Ang-(1-7)-NO-dependent pathway contributes to the sex-dependent consequences of programming on Na+ regulation in the proximal tubules of the kidney. Moreover, the RPTC retain both the sex and Beta-induced phenotype of the adult and may reflect an appropriate cell model of fetal programming.

Planning on the 4-disk version of the Tower of London (TOL4) was examined in stroke patients and unimpaired controls. Overall TOL4 solution scores indicated impaired planning in the frontal stroke but not non-frontal stroke patients. Consistent with the claim that processing the relations between current states, intermediate states, and goal states is a key process in planning, the domain-general relational complexity metric was a good indicator of the experienced difficulty of TOL4 problems. The relational complexity metric shared variance with task-specific metrics of moves to solution and search depth. Frontal stroke patients showed impaired planning compared to controls on problems at all three complexity levels, but at only two of the three levels of moves to solution, search depth and goal ambiguity. Non-frontal stroke patients showed impaired planning only on the most difficult quaternary-relational and high search depth problems. An independent measure of relational processing (viz., Latin square task) predicted TOL4 solution scores after controlling for stroke status and location, and executive processing (Trail Making Test). The findings suggest that planning involves a domain-general capacity for relational processing that depends on the frontal brain regions.

In the absence of supportive care, exposing Göttingen minipigs to γ-radiation doses of less than 2 Gy achieves lethality due to hematopoietic acute radiation syndrome. Doses of 2 to 5 Gy are associated with an accelerated hematopoietic syndrome, characterized by villus blunting and fusion, the beginning of sepsis, and a mild transient reduction in plasma citrulline concentration. We exposed male Göttingen minipigs (age, 5 mo; weight, 9 to 11 kg) to γ-radiation doses of 5 to 12 Gy (total body; (60)Co, 0.6 Gy/min) to test whether these animals exhibit classic gastrointestinal acute radiation syndrome (GI-ARS). After exposure, the minipigs were monitored for 10 d by using clinical signs, CBC counts, and parameters associated with the development of the gastrointestinal syndrome. Göttingen minipigs exposed to γ radiation of 5 to 12 Gy demonstrate a dose-dependent occurrence of all parameters classically associated with acute GI-ARS. These results suggest that Göttingen minipigs may be a suitable model for studying GI-ARS after total body irradiation, but the use of supportive care to extend survival beyond 10 d is recommended. This study is the first step toward determining the feasibility of using Göttingen minipigs in testing the efficacy of candidate drugs for the treatment of GI-ARS after total body irradiation.

A flash adjacent to the path of a moving object appears behind the moving object: the 'flash-lag effect'. We sought to test the flash-lag effect with a 'click' instead of a flash: a white triangle horizontally traversed the screen at a constant 12 degrees /s passing through a fixation cross in the presence of a quiet click. The subject judged whether the click occurred before or after the triangle passed through the cross. To be perceived as co-instantaneous events, the click had to be presented 127 ms after the moving triangle reached the cross (a 'click-lead' effect, providing falsification of predictive accounts of the flash-lag effect), as opposed to a standard flash-lag effect condition where a flashed triangle replaced the click and had to appear 60 ms before the moving triangle to appear aligned. With the auditory versus visual processing speed advantage considered, the neural time required to calculate a moving object's position is constant, independent of the modality of the flag.

A sudden luminance increment on a moving stimulus was perceived significantly along the trajectory, in the direction of motion, from its displayed position. A nonlinear relationship with stimulus speed, for a Fröhlich-like illusion, but not for the luminance-increment illusion, challenges certain models of spatial mislocalisation and argues for different processes underlying the two illusions.

The research examined whether verbal learning and memory impairment previously observed 1 year after left hemisphere stroke endures over a longer period and whether stroke sufferers compensate for their impairments using working memory.Twenty-one persons with left hemisphere lesions; 20 with right hemisphere lesions only and 41 matched controls completed the Hopkins Verbal Learning Test-Revised (HVLT-R), a working memory test (Letter-Number Sequencing, LNS) and the Boston Naming Test (BNT).Persons with left hemisphere damage performed more poorly on HVLT-R than controls. They showed poorer immediate recall, delayed recall, recognition and learning, but intact retention, suggesting an encoding impairment. BNT and LNS scores predicted recall in this group. HVLT-R performance of persons with right hemisphere lesions only was comparable to controls. BNT (not LNS) predicted recall in these groups.Persons with left hemisphere damage relied more on working memory and recruited diverse left hemisphere regions to compensate for their impaired encoding.Tasks requiring verbal encoding and memory are effortful following left hemisphere stroke. This should be recognized and accommodated.

With repeated exposure, people become better at identifying presented items and better at rejecting items that have not been presented. This differentiation effect is captured in a model consisting of item detectors that learn estimates of conditional probabilities of item features. The model is used to account for a number of findings in the recognition memory literature, including (a) the basic differentiation effect (strength-mirror effect), (b) the fact that adding items to a list reduces recognition accuracy (list-length effect) but extra study of some items does not reduce recognition accuracy for other items (null list-strength effect), (c) nonlinear effects of strengthening items on false recognition of similar distractors, (d) a number of different kinds of mirror effects, (e) appropriate z-ROC curves, and (f) one type of deviation from optimality exhibited in recognition experiments.

Spatial projection and temporal integration are two prominent theories of visual localization for moving stimuli which gain most of their explanatory power from a single process. Spatial projection theories posit that a moving stimulus' perceived position is projected forwards in order to compensate for processing delays (Eagleman & Sejnowski, 2007; Nijhawan, 2008). Temporal integration theories (Krekelberg & Lappe, 2000) suggest that an averaging over positions occupied by the moving stimulus for a period of time is the dominant process underlying perception of position. We found that when magnocellular (M) pathway processing was reduced, there were opposite effects on localization judgments when a smooth, continuous trajectory was used, compared to when the moving object suddenly appeared, or suddenly reversed direction. The flash-lag illusion was decreased for the continuous trajectory, but increased for the onset and reversal trajectories. This cross-over interaction necessitates processes additional to those proposed by either the spatial projection or temporal integration theories in order to explain the perception of the position of moving stimuli across all our conditions. Differentiating our onset trajectory conditions from a Frohlich illusion, in a second experiment, we found a null Frohlich illusion under normal luminance-defined conditions, significantly smaller than the corresponding flash-lag illusion, but significantly increased when M processing was reduced. Our data are most readily accounted for by Kirschfeld and Kammer's (1999) backward-inhibition and focal attention theory.

We previously reported that induction of diabetes in estrogen-depleted, hypertensive mRen2.Lewis (mRen2) female rats leads to significant albuminuria, proteinuria and tubulointerstial oxidative stress at 28 days. The current study assessed the time course for the development of proteinuria and peptidase activities in the urine of the diabetic hypertensive mRen2 to begin to establish potential biomarkers of renal injury in this model. Heterozygous mRen2 underwent ovariectomy and diabetes was induced by a single administration of streptozotocin (65 mg/kg; STZ) at 15 weeks of age. Urinary samples were taken prior to (day 0) and 5 and 28 days following STZ. Aspartyl peptidases were assayed with the quenched fluorescent substrate Mca-GWPILFFRLW(Dnp)R in the presence or absence of the inhibitor pepstatin. Enzyme activities were expressed as nmols Mca per 30 min per mg creatinine. Pepstatin-sensitive activity [IC50 ∼ 0.4 nM] was detectable in the pre-diabetic urines [26 ± 9; n=8]; however, the diabetic rats exhibited a significant increase in urinary activity at days 5 and 28 [184 ± 25 and 204 ± 53, respectively; p

A Vernier-offset illusion induced by rotating lines, introduced by Matin et al (1976 Perception & Psychophysics20 138–142) was re-examined using onset, offset, and reverse trajectories inspired by flash-lag illusion research, with both Vernier and alignment-with-vertical judgments being recorded. The pattern of illusions found was generally in agreement with a differential latency of stimulus ends account described by those authors, although certain variants of modern spatial projection theories, and a differential latency of attribute account, could also accommodate much of the data.

The authors present the results of their analysis of an auto-associator for use with sparse representations. Their recognition model using it exhibits a list-length effect but no list-strength effect, a dissociation that current models have difficulty producing. Data on the effects of similarity and strengthening that indicate a dissociation between recognition and frequency judgments are also addressed. Receiver operating characteristic curves for the model have slopes between 0.5 and 1.0 and achieve this ratio in a novel way. The model can also predict latencies naturally. The authors' cued-recall model uses an architecture similar to that of the recognition model and where applicable the same parameters. It predicts appropriate amounts of retroactive interference, and analysis reveals an output competition process that relies on distributed representations and has not been proposed before.

The brightness of a small incremental flash was found to be considerably suppressed in the vicinity of a moving visual stimulus (effect size, d, up to 6) and less so around a stationary stimulus. The pattern of suppression was mapped and extended 3.5 degrees away from a stationary stimulus and 10.5 degrees behind, and ahead of, a moving stimulus. A second experiment found that dark flashes appeared less dark in the presence of an inducing stimulus of either polarity. Combined results suggest that perceived contrast was being suppressed, in all cases by an inducing stimulus of lesser contrast, and in most cases by an inducing stimulus of lesser luminance. These findings were compared with a number of recent models of the perception of the position of moving visual stimuli. These assume that in the wake of such a stimulus, at certain retinal or cortical areas, there is a region of neural inhibition and that, preceding them, there is a (bow-wave-like) region of neural excitation. The current findings confirm the inhibitory, but not the excitatory, assumptions in these theories.

The flash-lag effect occurs when a flash abreast of a smoothly moving object is perceived to spatially lag the moving object. The postdiction accounts of this effect assume either that the flash ‘resets’ motion detectors [Science 287 (2000) 2036], or that position information is not computed for moving objects until it is needed [Trends in the Neurosciences 25 (2002) 293], the latter view having also been proposed by Brenner and Smeets [Vision Research 40 (2000) 1645]. According to these accounts, events occurring before the flash should not change the magnitude of the flash-lag effect. In our experiment, pre-exposure of the moving object as a stationary stimulus, for as little as 50 ms before the flash occurred, significantly reduced the flash-lag effect.

An object briefly flashed adjacent to the path of another moving object appears to spatially lag the moving object in the direction of its motion: the 'flash-lag effect'. A simple differential lag model account of this effect suggests that it occurs because the moving object activates motion detectors in the faster magnocellular pathway, whereas the flashed object does not. This model was tested by reducing M-pathway involvement using isoluminant stimuli. All four participants, who were university undergraduate students, were exposed to eight conditions, involving all possible combinations of moving and flashing objects coloured either white or green, shown against either a grey or a black background. Green objects were equiluminant with the grey background. The magnitude of the flash-lag effect was found using the method of constant stimuli. No reliable support was found for the hypothesis that equiluminance of the moving object reduces the flash-lag effect. Instead an interaction was found where there was an effect of equiluminance on the flash, but only when the moving object was not equiluminant. Such data is problematic for this and other simple differential lag models of the flash-lag effect.

Determining how the visual system locates moving stimuli continues to be an experimental and theoretical challenge. By making a moving visual stimulus equiluminant with its background, and immersing it in luminance noise, the spatial lead it normal enjoys over a flashed stimulus (the flash-lag illusion) was completely eliminated (the illusion was actually reversed for 6 out of 11 participants). As this manipulation is typically used to reduce Magnocellular (M) visual pathway processing, this is strong evidence that processing in this pathway advances the moving stimulus' perceived position. However, when the flashed stimulus was also made equiluminant in luminance noise, the illusion reappeared, indicating that M pathway processing contributed to its perception too. The presence of the illusion when both stimuli were equiluminant in luminance noise indicates that the illusion can be generated in the absence of M cell activation. To explicate the result with moving stimuli, we displayed two adjacent moving stimuli, one luminance-modulated, and the other equiluminant in noise. The latter was perceived to significantly lag the former (an 'M-P-Hess' illusion), and 39% of the difference in flash-lag illusions, with comparable moving stimulus contrasts, could be accounted for by this illusion.

The illusion of a single pulse of light seen as two flashes under certain viewing conditions has been known for nearly a century. The sound-induced flash illusion (SIFI, Shams 2000) is another example of extra flashes being reported beyond what is presented (‘fission’), but here in the context of co-occuring beeps. There have also been reports of ‘fusion’ in the SIFI: fewer flashes reported than presented, though Shams and colleagues did not find this. In the initial series of five experiments, the frequency of fusion vs fission was measured as a function of relative timings between the beeps and the flashes (SOAs). Particular care was taken to eliminate artefactual influences on the results: potential M pathway deficits in participants, afterimages, temporal resolution of flashes and beeps, expectancy effects and response biases. Without any cross-modal stimulation, there were small fission effects in reporting one flash and larger fusion effects in reporting three flashes. In comparison to this control condition, significant fission was found for SOAs within 100 msec, and fusion for SOAs beyond this value. Bowen (1989)’s explanation of unimodal multiple flash illusion was then applied to explaining SIFI fission effects. To do so, we modelled the biphasic temporal responses of actual fast ON- and OFF- midget parasol M cells to visual stimuli used in SIFI research. Whether auditory stimuli – beeps – direct attention to short duration peaks in neural responding, thus biasing the response of the observer in reporting the number of ‘transient’ events was considered. It is shown that for a square wave temporal profile, such response bias could easily be the case, especially given that three or four beeps rarely yield an illusion of more than two flashes. To eliminate these potential artefacts, a novel approach was developed: the use of a sawtooth temporal profile (either on or off) to create one physical transient in luminance for the sound to effect.

We report data from eight participants who made alignment judgements between a moving object and a stationary, continuously visible ‘landmark’. A reversing object had to overshoot the landmark by a significant amount in order to appear to reverse aligned with it. In addition, an adjacent flash irrelevant to the judgment task reliably increased this illusory ‘foreshortening’. This and other results are most simply explained by a model in which the flash causes attentional capture, complemented by processes of temporal integration, or backward inhibition, and object representation. A flash used to probe the perception of a moving object’s position disrupts that very perception.