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CRISPR-Cas defense systems have been naturally coopted for guide RNA-directed transposition by Tn7 family bacterial transposons. We find cyanobacterial genomes are rich in Tn7-like elements, including most of the known guide RNA-directed transposons, the type V-K, I-B1, and I-B2 CRISPR-Cas based systems. We discovered and characterized an example of a type I-D CRISPR-Cas system which was naturally coopted for guide RNA-directed transposition. Multiple novel adaptations were found specific to the I-D subtype, including natural inactivation of the Cas10 nuclease. The type I-D CRISPR-Cas transposition system showed flexibility in guide RNA length requirements and could be engineered to function with ribozyme-based self-processing guide RNAs removing the requirement for Cas6 in the heterologous system. The type I-D CRISPR-Cas transposon also has naturally fused transposase proteins that are functional for cut-and-paste transposition. Multiple attributes of the type I-D system offer unique possibilities for future work in gene editing. Our bioinformatic analysis also revealed a broader understanding of the evolution of Tn7-like elements. Extensive swapping of targeting systems was identified among Tn7-like elements in cyanobacteria and multiple examples of convergent evolution, including systems targeting integration into genes required for natural transformation.

Background Mobility and cognitive impairments are often associated with increased fall risk among people with multiple sclerosis (PwMS). However, evidence on the concurrent assessment of gait or balance and cognitive tasks (dual-task) to predict falls appears to be inconsistent. Objective To summarize the ability of gait or balance dual-task testing to predict future falls among PwMS. Methods Seven databases including PubMed, Embase, Web of Science, Scopus, CINHAL, SPORTDiscuss, and PsycINFO were searched from inception to May 2022. Two independent reviewers identified studies that performed a dual-task testing among adults with multiple sclerosis and monitored falls prospectively for at least 3 months. Both reviewers also evaluated the quality assessment of the included studies. Results Eight studies with 484 participants were included in the review. Most studies (75%) indicated that dual-task testing and dual-task cost did not discriminate prospective fallers (⩾1 fall) and non-fallers (0 fall) and were not found as predictors of future falls. However, dual-task cost of walking velocity (OR = 1.23, 95% CI 0.98-4.45, P = .05) and dual-task of correct response rate of serial 7 subtraction (OR = 1.34, 95% CI 1.04-3.74, P = .02) were significantly associated with increased risk of recurrent falls (≥2 falls). Pattern of cognitive-motor interference was also associated with an increased risk of falling. All studies presented with strong quality. Conclusion The scarce evidence indicates that dual-task testing is not able to predict future falls among PwMS. Further research with more complex motor and cognitive tasks and longer-term fall monitoring is required before dual-task testing can be recommended as a predictor of future falls in this population.

BACKGROUND: Level and non-level transfers are essential tasks of daily living for wheelchair users. Minimal research has examined the role of shoulder pain and fear of falling on transfer quality. The purpose of this study is to (1) examine the association between shoulder pain, fear of falling (FoF) and transfer quality and (2) explore the feasibility of assessing non-level transfers to-and-from the floor. METHODS: Cross-sectional design was used to explore shoulder pain, FoF, and transfer quality in 30 manual wheelchair users (aged 18-42; 15 males). Participant demographic information (age, sex, race, disability, and years using wheelchair), Spinal Cord Injury-Fall Concern Scale (SCI-FCS), and Wheelchair User Shoulder Pain Index (WUSPI) was collected. Three types of transfers: (1) level, (2) uphill, and (3) floor-to-table were graded by a trained researcher using the Transfer Assessment Instrument (TAI) 3.0. Kruskal–Wallis test was used to determine differences in transfer quality based on condition. Spearman correlation was used to determine associations between demographic data, WUSPI, SCI-FCS, and transfer quality scores. RESULTS: All participants safely completed the uphill non-level transfer; 27 safely completed the floor-to-table non-level transfer. Statistical analysis revealed no difference in TAI score across transfer conditions. Spearman correlation revealed a significant correlation between WUSPI and SCI-FCS scores (r = .68, P = .01) and WUSPI and uphill TAI scores (r = -.45, P = .01). CONCLUSION: Increases in shoulder pain are related to decreased uphill transfer quality and increased FoF. Non-level transfers to-and-from the floor are feasible within clinical or laboratory settings.

Gait and balance impairments are associated with falls and reduced quality of life among survivors of stroke (SS). Effective methods to assess these impairments at-home and in-clinic can help reduce fall risks and improve functional outcomes. Smartphone technology may be able to evaluate these impairments. This review aims to summarize the validity, reliability, sensitivity, and specificity of smartphone applications for determining gait and balance disorders in SS.Database search through PubMed, Web of Science, Scopus, CINAHL, and SportDiscuss was conducted to retrieve studies that explored the use of smartphone-based applications for assessing gait and balance disorders in SS. Two independent reviewers screened potential articles to determine eligibility for inclusion. Eligible studies were summarized for participant and study characteristics, validity, reliability, sensitivity, and specificity of smartphone assessments. Methodological quality assessment of studies was performed using the NIH Quality Assessment Tool.Seven cross-sectional studies were included in the review. Quality assessment revealed all studies had low risk of bias. Three of the included studies examined the validity, four examined the reliability, and two examined the specificity and sensitivity of smartphone-based application assessments of gait and balance in SS. Studies revealed that smartphones were valid, reliable, specific, and sensitive. Six of the seven included studies intended their use for SS and one study for clinicians.Preliminary evidence supports that smartphone-based gait and balance assessments are valid, reliable, sensitive, and specific in SS in laboratory settings. Future research is needed to test smartphone-based gait and balance assessments in home settings and determine optimal wear sites for assessments.IMPLICATIONS FOR REHABILITATIONSmartphone-based gait and balance assessments are feasible, valid and reliable for survivors of strokeThe findings may guide future research to standardize the use of smartphone to assess gait and balance in this population.The remote use of smartphone-based assessments to predict fall risk in survivors of stroke needs to be explored.

Cupping therapy has been popular in elite athletes in recent years. However, the effect of cupping therapy on reducing muscle fatigue has not been investigated. The purpose of this study was to investigate the immediate and delayed effects of cupping therapy on reducing biceps brachii fatigue during biceps curls. Twelve healthy untrained participants were recruited for this repeated-measures study. Cupping therapy (–300 mmHg pressure for 5 min) and sham control (no negative pressure for 5 min) were applied after biceps fatigue induced by performing repeated biceps curls at 75% of the 10 repetitions of maximum of the non-dominant hand. Surface electromyography (EMG) with spectral analyses [mean frequency (MNF), median frequency (MDF), and spectral moments ratio (SMR)] were used to assess muscle fatigue during the fatigue task. EMG signals during the first 10 repetitions and the last 10 repetitions of biceps curls were used to assess neuromuscular fatigue. There were significant decreases in MNF and MDF and a significant increase in SMR immediately and 24 h after the sham control (no intervention). When comparing the MNF, MDF, and SMR after cupping therapy to the sham control, there was no significant immediate effect on reducing muscle fatigue. However, there was a significant delayed effect on improving recovery following fatigue for the cupping therapy compared to the sham control (MNF changes: sham 0.87 ± 0.02 vs. cupping 0.91 ± 0.02, p < 0.05; MDF changes sham: 0.85 ± 0.03 vs. cupping: 0.91 ± 0.02, p < 0.05; SMR changes: sham 1.89 ± 0.15 vs. cupping 1.58 ± 0.13, p < 0.05). The findings of this study demonstrate that there is a time effect of cupping therapy for reducing muscle fatigue. Cupping therapy is effective on reducing biceps brachii muscle fatigue after 24 h.

Lifelong learning opportunities are readily accessible through the hybridization of digital learning contexts—from formal to informal—in today's globally networked knowledge society. As such, expanded learning opportunities generate a continuum of learning contexts and experiences mediated through digital technology. Consequently, there is an urgent need to actively examine the interconnections and complex relations between what is learned in formal university scenarios and the everyday learning that happens outside of the classroom, particularly the informal learning that is afforded through expanded and emerging digital contexts. The current research problem illustrates that expanded and emerging professional development scenarios require new pedagogical designs for empowering lifelong learners to harness the affordances of the web across both formal and informal contexts and practices. This study outlines ways in which students shape their learning ecologies in virtual contexts to support formal academic learning in online higher education. The paper presents qualitative results from a larger mixed methods interpretive case study. The multicase and multisite study examines three fully online graduate programmes in Education and Digital Technology during the 2017–18 academic year, collecting data in the form of online programme documentation, student interviews and online participant observation. Purposeful and criterion sampling were used to select 13 participants across three sites in Spain, the UK and the USA. The study was underpinned by a lifelong learning ecologies theoretical perspective to analyse learning processes across a continuum of practices and contexts. Findings illustrate how students conceive of, as well as how they organize their learning ecologies through a unique configuration of activities, digital resources and networked social support, indicating that academic programmes and teachers have an essential role in empowering student learning ecologies across contexts, recognizing past trajectories and supporting the development of valued disciplinary practices and perspectives across a continuum of learning. [ABSTRACT FROM AUTHOR] uracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background Physical activity may benefit health and reduce risk for chronic complications in normal and people with diabetes and peripheral vascular diseases. However, it is unclear whether leg muscle fatigue after weight-bearing physical activities, such as brisk walking, may increase risk for plantar tissue injury. In the literature, there is no evidence on the effect of muscle fatigue on plantar pressure after various walking intensities. The objectives of this study were to investigate the effects of various walking intensities on leg muscle fatigue and plantar pressure patterns. Methods A 3 × 2 factorial design, including 3 walking speeds (1.8 (slow and normal walking), 3.6 (brisk walking), and 5.4 (slow running) mph) and 2 walking durations (10 and 20 min) for a total of 6 walking intensities, was tested in 12 healthy participants in 3 consecutive weeks. The median frequency and complexity of electromyographic (EMG) signals of tibialis anterior (TA) and gastrocnemius medialis (GM) were used to quantify muscle fatigue. Fourier transform was used to compute the median frequency and multiscale entropy was used to calculate complexity of EMG signals. Peak plantar pressure (PPP) values at the 4 plantar regions (big toe, first metatarsal head, second metatarsal head, and heel) were calculated. Results Two-way ANOVA showed that the walking speed (at 1.8, 3.6, 5.4 mph) significantly affected leg muscle fatigue, and the duration factor (at 10 and 20 min) did not. The one-way ANOVA showed that there were four significant pairwise differences of the median frequency of TA, including walking speed of 1.8 and 3.6 mph (185.7 ± 6.1 vs. 164.9 ± 3.0 Hz, P = 0.006) and 1.8 and 5.4 mph (185.7 ± 6.1 vs. 164.5 ± 5.5 Hz, P = 0.006) for the 10-min duration; and walking speed of 1.8 and 3.6 mph (180.0 ± 5.9 vs. 163.1 ± 4.4 Hz, P = 0.024) and 1.8 and 5.4 mph (180.0 ± 5.9 vs. 162.8 ± 4.9 Hz, P = 0.023) for the 20-min duration. The complexity of TA showed a similar trend with the median frequency of TA. The median frequency of TA has a significant negative correlation with PPP on the big toe ( r = -0.954, P = 0.003) and the first metatarsal head ( r = -0.896, P = 0.016). Conclusions This study demonstrated that brisk walking and slow running speeds (3.6 and 5.4 mph) cause an increase in muscle fatigue of TA compared to slow walking speed (1.8 mph); and the increased muscle fatigue is significantly related to a higher PPP.

The exploration of augmented reality's (AR) potential in higher education teaching and learning demonstrates an impressive scope of critical inquiry. Online higher education (OHE) represents a transformation in learning practices and educational paradigms on a global scale, with a significant opportunity for the application of AR through e-learning. The overarching goal of the current study is to understand how the presence of AR applications in an OHE multimedia program impacts student learning. The current conceptual study aims to formulate design and development requirements for an AR application, aiming to understand how a user-centred design (UCD) approach could frame such a process. The overarching goal is to design AR resources which enhance student learning in multimedia education. Implementing a user-centred approach ensures that learners are taken into account from the beginning of the design process and throughout the iterative design lifecycle. The current paper presents the results from the first phase of a multi-stage research project. First, conceptually designed personas, scenario reviews, and user journey mappings were developed based on identified learner needs and AR system requirements previously identified. The results show evaluation techniques use within a UCD process while revising AR scenarios from the learner's perspective and exploring design requirements to ensure the feasibility of the AR application. An implication of our study is to demonstrate the value of a range of evaluation techniques presented here using a user-centred design approach, which can be used to design and develop future AR and eXtended Reality (XR) technologies in educational scenarios.

Background Methods to effectively assess gait and balance impairments are necessary to guide interventions among people with Multiple Sclerosis (PwMS). Smartphone-based evaluations are becoming popular due to the ubiquitous use of smartphones in society. Objective To determine the current state of smartphone applications that assess gait and balance among PwMS. Methods Two independent reviewers screened articles retrieved from PubMed, Web of Science, Scopus, CINAHL, and SportDiscuss. Articles meeting eligibility criteria were summarized and qualitatively discussed. Participant characteristics, validity, reliability, sensitivity and specificity measures, and main results of smartphone-based gait and balance evaluations were summarized. Methodological quality appraisal of the studies was performed using the quality assessment tool for observational cohort and cross-sectional studies. Results Eight articles were included in this review. The studies present mostly with low risk of bias. All studies successfully tested the use of smartphone applications in assessing gait and balance among PwMS. In total, 75% of the studies evaluated the validity; 38% evaluated the reliability, sensitivity, and specificity of smartphone applications to assess gait and balance. Of those, all studies except one found smartphone applications to be appropriately valid, reliable, sensitive, and specific in assessing gait and balance. Most studies (88%) reported PwMS and clinicians as their intended users. Conclusion There is evidence supporting the use of smartphone applications to assess gait and balance among PwMS. Future studies should further examine the psychometric properties of smartphone-based gait and postural control assessments as well as the sensitivity and specificity to improve the interpretation of the results.

Systematic review and meta-analysis. Traditional forms of upper-body moderate intensity exercise consistently provide little cardiovascular benefits for persons with spinal cord injury (PwSCI). Explorations of new training methods are vital to improve cardiovascular fitness among PwSCI. This study sought to evaluate the effectiveness of vigorous training on cardiorespiratory fitness in PwSCI. Database search through PubMed, Web of Science, Scopus, SportDiscus, and Cumulative Index of Nursing and Allied Health Literature (CINAHL) was conducted from the databases’ inception to November 2020 to identify relevant exercise studies with PwSCI. Two independent reviewers screened articles for inclusion. Data were extracted from included studies and methodological quality evaluated. Sixteen trials (eight pre-post trials and eight controlled trials [CTs]) with a total of 145 participants were analyzed. Results from pre-post studies revealed significant improvements in cardiorespiratory fitness following high-intensity interval training (HIIT) (Peak Oxygen Uptake [VO2peak], standardized mean difference [SMD] = 0.81; 95% CI 0.23–1.39; P

Context/objective: To examine personal (athletic classification, age, sex, body mass index, duration of disability, tactile sensation of lower extremities) and wheelchair (kneeling plate angle) factors associated with increased pretibial skin pressures in elite wheelchair racers. Design: Cross-sectional study. Setting: University-based laboratory in Champaign, USA. Participants: A convenience sample of elite wheelchair races with traumatic spinal cord injury and spinal disease were recruited for participation. Interventions: Interface pressure mapping was used to examine athletes’ average and peak pretibial skin pressures in their own racing wheelchairs during static and dynamic (propulsive) conditions on a dynamometer. Outcome measures: The study examined associations between personal and wheelchair factors and pressure, differences in pressure between static and dynamic conditions, and the influence of athletic classification (T53 vs. T54) on kneeling plate angle preference and skin pressure magnitudes. Results: Increased kneeling plate angle was moderately associated with dynamic pressures. T53 athletes utilized more vertical kneeling angles and experienced larger average and peak pressures during propulsion. Duration of disability was negatively associated with all measures of pressure. Overall, mean dynamic peak pressure was significantly greater than mean static peak pressure. Conclusion: This pilot study represents a first step in understanding the influence of user interface on potentially injurious skin pressures in wheelchair racers. Vertical kneeling plate configurations were associated with increased pressures while increased years with disability was associated with lower pretibial pressures. In addition, T53 athletes with less trunk function may be at a greater risk for experiencing larger interface pressures than T54 athletes.

Objective(s) To summarize the viability of smartphone applications for determining gait dysfunctions and balance disorders in stroke survivors (SS). Data Sources A database search of peer-reviewed articles published in English through PubMed, Web of Science, Scopus, CINAHL, and SportDiscuss was conducted in January 2021. The search strategy included a combination of the terms: smartphone, stroke, gait, balance, and postural control. Study Selection Studies that explored the use of smartphone-based applications in laboratory and/or home-based settings for assessing gait and balance among SS. Data Extraction Two independent reviewers screened potential articles to determine their eligibility for inclusion in the review. Eligible studies were summarized for participant and study characteristics, validity, reliability, sensitivity, and specificity of smartphone assessments. Methodological quality assessment of all studies was performed. Data Synthesis Seven cross-sectional studies were included in this review. Quality assessment revealed all studies had a low risk of bias. In total, 43% of the included studies examined the validity, 57% examined the reliability, and 29% examined the specificity and sensitivity of smartphone-based application assessments of gait and balance in SS. All those studies revealed that smartphones were valid, reliable, specific and sensitive to evaluate gait and balance in SS. Six of the 7 included studies intended their use for SS and one study for clinicians. Conclusions Gait and balance impairments are key fall risk factors among SS. Effective methods to assess these impairments may help reduce fall risks, while also improving functional outcomes. The results provide evidence that smartphone-based gait and balance assessments are a viable option in SS in laboratory settings. Future research is needed to test smartphone-based gait and balance assessments in home settings and determine optimal wear sites for assessments. Author(s) Disclosures JJS is principal owner of Sosnoff Technologies LLC.

Objective The aim of the study was to examine the circumstances surrounding the worst fall experienced by full-time manual wheelchair users in the past 12 mos, the recovery process, and influence on community participation. Design A mixed-method research study was conducted. Semistructured interviews were conducted to understand the circumstances of the worst fall experienced and the recovery process. A quantitative fear of falling assessment and the community participation indicators were used to further evaluate the influence of the fall. Results There were 20 manual wheelchair users (mean ± SD, 47 ± 13 yrs, 55% male). Falls most commonly occurred outside during wheelchair propulsion. Falls were attributed to both intrinsic and extrinsic factors. Seventy percent of participants reported a fear of falling and 80% required assistance to recovery. No significant correlations were found between fall frequency and community participation indicator scores. Participants who needed assistance to recover (56.70 ± 17.66) had lower community participation indicator importance scores compared with participants able to recover independently (88.93 ± 22.13), P = 0.05. Conclusions Falls are complex and most manual wheelchair users need assistance to recover. Comprehensive programs including education on prevention and postfall management are needed. Results may increase understanding of the circumstances associated with falls and inform the development of evidenced-based clinical practice guidelines.

This pilot study investigated the relationship between personal and wheelchair factors on skin pressures at the ischial tuberosity in wheelchair basketball players. Seventeen wheelchair basketball players (7 male and 10 female) were evaluated during static and dynamic propulsive conditions while peak pressure index and peak pressure gradient were recorded with an interface pressure mat. The results showed that greater seat dump angles and backrest heights were negatively associated with the peak pressure index. Therapeutic cushion use was moderately associated with a reduced peak pressure gradient. Higher-class players used chair configurations associated with augmented pressure; however, classification status alone was not associated with pressure magnitude. Body mass index was negatively correlated with the static peak pressure gradient at levels approaching significance (p

Further developments in the membrane-filter DNA procedure for determining the somatic cell content of milk samples are described. A statistical experiment has been done comparing the membrane-filter test to the direct microscopic somatic cell count. Under conditions of the assay a relationship of 0.093 absorbance unit per million cells was obtained at a wavelength of 490 nm. The membrane filter technique is more precise than the direct microscopic count and is not subject to techician bias. A method is described for standardizing the procedure between and within laboratories based on use of lyophilized bovine somatic cells trapped on membrane filters as a calibration device.

Objective: To understand the circumstances surrounding the worst fall experienced by power wheelchair users in the past year and to examine injuries sustained and recovery methods. Design: A qualitative study using a semi-structured interview. Setting: Community. Participants: A self-selected volunteer sample of 19 power wheelchair users who utilize their device for at least 75% of mobility. The most common disability represented was cerebral palsy ( n = 8). The mean (SD) age of participants was 41.9 (7.6) years, who lived with their disability for a mean (SD) of 20.5 (8.62) years and used their current device for a mean (SD) of 3.9 (1.9) years. Intervention: None. Main outcome measures: A semi-structured interview examined the circumstances surrounding the worst fall experienced in the past year, injuries sustained and recovery techniques used. Results: Upon examination of the circumstances of the worst fall, four main themes emerged: (1) action-related fall contributors, (2) location of falls, (3) fall attributions and (4) time of fall. Each fall described was found to involve multiple factors. As a result of the fall, participants also reported the occurrence of physical injuries and a fear of falling. Physical injuries ranged from skin abrasion and bruises to fractures and head injuries. Participants also reported that fear of falling diminished their desire to participation in activities they enjoyed doing. Finally, most participants reported the need for physical assistance to recover from a fall. Conclusion: Participant descriptions provide an in-depth description of the circumstances and aftermath of falls experienced by power wheelchair users.

The bacterial transposon Tn7 is distinguished by the levels of control it displays over transposition and its capacity to utilize different kinds of target sites. Transposition is carried out using five transposon-encoded proteins, TnsA, TnsB, TnsC, TnsD, and TnsE, which facilitate transfer of the element while minimizing the chances of inactivating host genes by using two pathways of transposition. One of these pathways utilizes TnsD, which targets transposition into a single site found in bacteria ( attTn7 ), and a second utilizes TnsE, which preferentially directs transposition into plasmids capable of moving between bacteria. Control of transposition involves a heteromeric transposase that consists of two proteins, TnsA and TnsB, and a regulator protein TnsC. Tn7 also has the ability to inhibit transposition into a region already occupied by the element in a process called target immunity. Considerable information is available about the functional interactions of the Tn7 proteins and many of the protein–DNA complexes involved in transposition. Tn7-like elements that encode homologs of all five of the proteins found in Tn7 are common in diverse bacteria, but a newly appreciated larger family of elements appears to use the same core TnsA, TnsB, and TnsC proteins with other putative target site selector proteins allowing different targeting pathways.

The purpose of this study was to develop an understanding of how collabora- tion among teachers from several schools, and with university researchers, facilitated these el- ementary teachers as they attempted change in their practices. The collaboration effort was built into an in-service project for elementary teachers that focused on assisting teachers to implement a curriculum emphasizing problem-centered learning in science. The project in- volved 24 teachers in a 3-week summer workshop and an intensive follow-up research pro- gram during the following school semester. Our understanding of the relationship between change and the collaborative experience was developed from multiple data sources, including transcripts of interviews and group meetings, lesson plans and other teacher produced arti- facts, and field notes from classroom observations. Our analysis of the data indicates that col- laboration facilitates change because it provides opportunities for teachers to learn both content and pedagogical knowledge from one another, encourages teachers to be risk takers in implementing new ideas, and supports and sustains the processes of individual change in sci- ence teaching. © 1997 John Wiley & Sons, Inc. Sci Ed 81:51 - 65, 1997.

This study focuses on the use of paired keyboards attached to a single microcomputer as a means to facilitate internet exploration. A classroom teacher with nineteen years experience and an educator worked with an intact third grade class of twenty-nine public school students. Children worked in pairs, with one child considered as the knowledgeable other who, through interaction with a partner, might extend the partner's Zone of Proximal Development. This type of learning environment allowed for selective intervention among groups which facilitated and accelerated internet exploration and made the experience a much more successful and rewarding one. Interviews along with ongoing weekly observations were employed to examine this scaffolding approach while the students were on-line. The use of paired keyboards become, in a Vygotskian sense, a tool in children's learning. Review of the process indicated that this approach enabled students who were unfamiliar with either computers or the internet to be successful in their quest for information and global collaboration. The implication is that meaningful learning takes place when educators are creative in the way that computer hardware/software is used in support of facilitating education through internet exploration.

Two instructors with 7 classes and 165 students were in this study. The purpose of the study was to examine the effect of cooperative learning techniques and instruction with microcomputer-based laboratories on the achievement of preservice elementary teachers (with different operational levels of cognitive development) in acquiring integrated science process skills and enhancing formal thinking abilities. Cooperative learning is an environment in which students work in small, mixed-ability groups toward the same objectives. All students were pre and post-tested with two instruments: The Test of Integrated Process Skills (TIPS & TIPS II) and the Test of Logical Thinking (TOLT). Results showed that greater differences in the achievement on the TIPS test occurred in the setting where cooperative learning and MBLs were used. Test score gains on the TOLT test were similar across the four groups. Students with formal operational levels scored similar gains on the TIPS and TOLT tests as students of non-formal operational levels of development.

This paper describes a multiresolution approach to the visualization of surface data. The algorithms discussed allow the generation of arbitrary views of 3-dimensional surfaces. Image processing and texture mapping techniques are combined in a new 3-pass scanline algorithm to achieve smooth and continuous translations, rotations, and scale changes of large data sets. The implementation of the algorithms on a massively parallel SIMD video supercomputer, the Princeton Engine, allows the scenes to be generated interactively at video rates.