scholarly journals Haptic assistance that restricts use of redundant solutions is detrimental to motor learning

2019 ◽  
Author(s):  
Rakshith Lokesh ◽  
Rajiv Ranganathan
Keyword(s):  
Motor Learning ◽  
Multiple Solutions ◽  
Critical Issue ◽  
Motor Variability ◽  
The Individual ◽  
Haptic Assistance ◽  
Task Level

AbstractUnderstanding the use of haptic assistance to facilitate motor learning is a critical issue, especially in the context of tasks requiring control of motor variability. However, the question of how haptic assistance should be designed in tasks with redundancy, where multiple solutions are available, is currently unknown. Here we examined the effect of haptic assistance that either allowed or restricted the use of redundant solutions on the learning of a bimanual steering task. 60 college-aged participants practiced steered a single cursor placed in between their hands along a smooth W-shaped track of a certain width as quickly as possible. Haptic assistance was either applied at the ‘task’ level using a force channel that only constrained the cursor to the track, allowing for the use of different hand trajectories, or (ii) the ‘individual effector’ level using a force channel that constrained each hand to a specific trajectory. In addition, we also examined the effect of ‘fading’ – i.e., decreasing assistance with practice to reduce dependence on haptic assistance. Results showed all groups improved with practice - however, groups with haptic assistance at the individual effector level performed worse than those at the task level. Moreover, fading of assistance did not offer learning benefits over constant assistance. Overall, the results suggest that haptic assistance is not effective for motor learning when it restricts the use of redundant solutions.

scholarly journals Predicting Detached Housing Vacancy: A Multilevel Analysis

2022 ◽  
Vol 14 (2) ◽  
pp. 922
Author(s):  
Jaekyung Lee ◽  
Galen Newman ◽  
Changyeon Lee
Keyword(s):  
Multilevel Model ◽  
Local Environment ◽  
Critical Issue ◽  
Building Structure ◽  
Model Design ◽  
Vacancy Rate ◽  
City Center ◽  
Individual Housing ◽  
The Individual ◽  
Housing Vacancy

Urban shrinkage is a critical issue in local small- and medium-sized cities in Korea. While there have been several studies to analyze the causes and consequences of vacancy increases, most have only focused on socioeconomic associations at larger scale and failed to consider individual housing level characteristics, primarily due to a lack of appropriate data. Based on data including 52,400 individual parcels, this study analyzes the primary contributors to vacant properties and their spatial distribution through a multilevel model design based on data for each parcel. Then, we identify areas at high risk of vacancy in the future to provide evidence to establish policies for improving the local environment. Results indicate that construction year, building structure, and road access conditions have a significant effect on vacant properties at the individual parcel level, and the presence of schools and hypermarket within 500 m are found to decrease vacant properties. Further, prediction outcomes show that the aged city center and areas with strict regulations on land use are expected to have a higher vacancy rate. These findings are used to provide a set of data-based revitalization strategies through the development of a vacancy prediction model.

scholarly journals High variability impairs motor learning regardless of whether it affects task performance

2018 ◽  
Vol 119 (1) ◽  
pp. 39-48 ◽  
Author(s):  
Marco Cardis ◽  
Maura Casadio ◽  
Rajiv Ranganathan
Keyword(s):  
Motor Learning ◽  
Task Performance ◽  
Null Space ◽  
Motor Task ◽  
Task Space ◽  
Movement Variability ◽  
Motor Variability ◽  
Different Dimensions ◽  
Left And Right

Motor variability plays an important role in motor learning, although the exact mechanisms of how variability affects learning are not well understood. Recent evidence suggests that motor variability may have different effects on learning in redundant tasks, depending on whether it is present in the task space (where it affects task performance) or in the null space (where it has no effect on task performance). We examined the effect of directly introducing null and task space variability using a manipulandum during the learning of a motor task. Participants learned a bimanual shuffleboard task for 2 days, where their goal was to slide a virtual puck as close as possible toward a target. Critically, the distance traveled by the puck was determined by the sum of the left- and right-hand velocities, which meant that there was redundancy in the task. Participants were divided into five groups, based on both the dimension in which the variability was introduced and the amount of variability that was introduced during training. Results showed that although all groups were able to reduce error with practice, learning was affected more by the amount of variability introduced rather than the dimension in which variability was introduced. Specifically, groups with higher movement variability during practice showed larger errors at the end of practice compared with groups that had low variability during learning. These results suggest that although introducing variability can increase exploration of new solutions, this may adversely affect the ability to retain the learned solution.NEW & NOTEWORTHY We examined the role of introducing variability during motor learning in a redundant task. The presence of redundancy allows variability to be introduced in different dimensions: the task space (where it affects task performance) or the null space (where it does not affect task performance). We found that introducing variability affected learning adversely, but the amount of variability was more critical than the dimension in which variability was introduced.

scholarly journals c-Kit-Mediated Overlapping and Unique Functional and Biochemical Outcomes via Diverse Signaling Pathways

2004 ◽  
Vol 24 (3) ◽  
pp. 1401-1410 ◽  
Author(s):  
Li Hong ◽  
Veerendra Munugalavadla ◽  
Reuben Kapur
Keyword(s):  
Signaling Pathways ◽  
Binding Sites ◽  
Cellular Proliferation ◽  
Critical Issue ◽  
Cellular Growth ◽  
Mitogen Activated Protein Kinase ◽  
Downstream Signaling ◽  
Kit Receptor ◽  
And Migration ◽  
The Individual

ABSTRACT A critical issue in understanding receptor tyrosine kinase signaling is the individual contribution of diverse signaling pathways in regulating cellular growth, survival, and migration. We generated a functionally and biochemically inert c-Kit receptor that lacked the binding sites for seven early signaling pathways. Restoring the Src family kinase (SFK) binding sites in the mutated c-Kit receptor restored cellular survival and migration but only partially rescued proliferation and was associated with the rescue of the Ras/mitogen-activated protein kinase, Rac/JNK kinase, and phosphatidylinositol 3-kinase (PI-3 kinase)/Akt pathways. In contrast, restoring the PI-3 kinase binding site in the mutated receptor did not affect cellular proliferation but resulted in a modest correction in cell survival and migration, despite a complete rescue in the activation of the PI-3 kinase/Akt pathway. Surprisingly, restoring the binding sites for Grb2, Grb7, or phospholipase C-γ had no effect on cellular growth or survival, migration, or activation of any of the downstream signaling pathways. These results argue that SFKs play a unique role in the control of multiple cellular functions and in the activation of distinct biochemical pathways via c-Kit.

Energy Adaptive and Max-Min based BFS Model for Route Optimization in Sensor Network

2020 ◽  
Vol 13 ◽  
Author(s):  
Kapil Juneja
Keyword(s):  
Energy Consumption ◽  
Sensor Network ◽  
Routing Protocol ◽  
Critical Issue ◽  
Route Optimization ◽  
Sensor Nodes ◽  
Hop Count ◽  
Intermediate Node ◽  
Comparative Results ◽  
The Individual

Background: The restricted energy and network life is a critical issue in the real-time sensor network. The occurrence of low-energy and faulty intermediate nodes can increase communication failure. The number of intermediate nodes affects the number of re-transmission, communication-failures, and increases the energy consumption on the routing path. The existing protocols take the greedy decision on all possible intermediate nodes collectively by considering one or more parameters. Objective: This work divides the distance between the source and destination into coverage-specific zones for restricting the hop-count. Now each zone is processed individually and collectively for generating the energy effective and failure preventive route. Methods: In this paper, the energy and coverage weighted BFS (Best First Model) algorithm is presented for route optimization in the sensor network. The max-min BFS is implied on sensor nodes of each zone and identified as the most reliable and effective intermediate node. The individual and composite weighted rules are applied to energy and distance parameters. This new routing protocol discovered the energy-adaptive route. Results: The proposed model is simulated on a randomly distributed network, and the analysis is done in terms of network life, energy consumption, hop count, and the number of route switching parameters. The comparative analysis is done against the MCP, MT-MR, Greedy, and other state-of-art routing protocols. Conclusion: The comparative results validate the significance of the proposed routing protocol in terms of energy effectiveness, lesser route switching, and improved the network life.

Cloud-Based Personalized Movement Student Learning

2018 ◽  
pp. 395-409
Author(s):  
Thomas Kourtessis ◽  
Andreas G. Avgerinos ◽  
Haralambos Tsiantis ◽  
Maria Liberi ◽  
Emmanouil Goufas
Keyword(s):  
Learning Disabilities ◽  
Motor Learning ◽  
Developmental Coordination Disorder ◽  
Individual Characteristics ◽  
Teaching Methodologies ◽  
Motor Dexterity ◽  
The Individual ◽  
Coordination Disorder ◽  
School Movement

This chapter presents a case study related to the development of an in-school framework that is concerned with the identification, assessment and interventional management of children with developmental coordination disorder and motor learning disabilities. The aim was to use reliable and tested procedures of identification and assessment as well as to adopt teaching methodologies that discover, reveal and use the individual characteristics of each child to reduce the limitations and to make in-school movement situations accessible to all students. The initial goal was not necessarily the immediate improvement of motor dexterity of the child, but the improvement of the psychological and socio-affective.

Emergence of Frequency-Dependent Motor Variability Within Supra-Second Auditory Cueing

2021 ◽  
pp. 003151252110407
Author(s):  
Premjit Khanganba Sanjram ◽  
Yogesh Kumar Shivhare
Keyword(s):  
Motor Learning ◽  
Essential Feature ◽  
Low Frequency ◽  
Auditory Stimuli ◽  
Cognitive Resources ◽  
Tone Frequency ◽  
Motor Variability ◽  
Stimulus Interval ◽  
Sensory Motor ◽  
Perceptual Property

Motor variability (MV) is an essential feature of the sensory motor system, and it plays an important role in sensory-motor learning. MV facilitates motor adaptation during auditory-motor synchronization (AMS). In AMS, individuals receive a series of similar auditory stimuli that come in a periodic manner at a fixed interval called an inter-stimulus interval (ISI). Peri-second ISI (1 second range) and supra-second ISI (>1 second) are differently processed, since these intervals involve different amount of cognitive resources. Supra-second ISI involves more top-down attention as compared to peri-second ISI. In this study we examined the effect of tone frequency (perceptual property of auditory stimuli) on predictive tapping and MV under peri-second and supra-second ranges. We examined the effect of tone frequency (a perceptual property of auditory stimuli) on predictive tapping and motor variability (MV) under short (peri-second) and long (supra-second) inter-stimulus intervals. Among 30 healthy participants (aged 18–35 years, M = 24.6 years), we randomly assigned equal numbers of these two inter-stimulus conditions to isochronous sound sequences. In their attempt to synchronize their motor responses with the tone, participants reproduced the ISI in their inter-tap intervals (ITIs). We analyzed their predictive tapping in terms of negative asynchrony (in which the tap occurs before the tone) and small positive asynchrony (0-100 ms), whereas we analyzed MV using the coefficient of variation (CV) of the ITI. We found that participants showed predictive tapping under short ISI, irrespective of the tone frequency. Moreover, their MV was unaffected by tone frequency. These findings imply that participants expressed MV in a predictive rather than reactive manner under short, but not long, ISI. Under long ISI, tone frequency had a significant effect on MV such that there was higher MV with the low-frequency than with the high-frequency tone. Thus, low-frequency tones are most suitable for auditory-motor learning in the supra-second range.

Criminal Law Measures to Combat Violent Crimes: International Experience and National Trends

2018 ◽  
Vol 9 (1) ◽  
pp. 352
Author(s):  
Zhandos Bahtybaevich ZHOLZHAKSYNOV
Keyword(s):  
Violent Crime ◽  
Criminal Law ◽  
Modern Society ◽  
Critical Issue ◽  
The State ◽  
Violent Crimes ◽  
Criminal Violence ◽  
Foreign Countries ◽  
The Individual ◽  
Criminal Legislation

The article is devoted to criminal law measures to resist criminal abuses related to violence. In modern society, the protection of individual rights and freedoms is one of the most important tasks. Within this task, the most critical issue is that of protection of the individual from criminal violence by criminal law measures. The problems of violent crime, despite all measures taken by the state and society, do not go into the past, but become relevant for modern society. Without exaggeration, they represent a social disaster that threatens the security of the individual, society and the state. The purpose of the article is to analyze the criminal law methods of combating violent crime, to study the criminal provisions relating to the use of violence in Kazakhstan's national criminal legislation and legislation in a number of foreign countries. The article examines the opinions of scientists on the nature and characteristics of criminal violence, the criminal law of Kazakhstan and the legislation of a number of foreign countries in terms of violent crimes, formulates conclusions and sets out the recommendations for the further improvement of the criminal protection of the individual against violent endeavors. On the basis of an examination of the theoretical material and experience of foreign countries in the field of countering violent crime, the author suggested ways of counteracting the mentioned crime, suggesting further improvement of the criminal legislation of the Republic of Kazakhstan, in the sphere of protecting the individual from criminal violence. The main provisions and conclusions of the article can be used in science and practice in addressing crime prevention, comparative characteristics of the criminal regulations regarding violence in Kazakhstan and foreign countries, as well as the subsequent reform of the criminal law in the field of the physical integrity of the individual.

Overview of epidemiology

2013 ◽  
Author(s):  
Blánaid Daly ◽  
Paul Batchelor ◽  
Elizabeth Treasure ◽  
Richard Watt
Keyword(s):  
Clinical Trials ◽  
Random Sample ◽  
Critical Issue ◽  
Dental Disease ◽  
New Materials ◽  
Human Race ◽  
Dental Services ◽  
Causal Factors ◽  
The Individual

How tall is the human race? What is meant by being short? Walking down the street, one will see people of various heights and a degree of variation exists. Some people are shorter than others, but when is someone abnormally so? How is it possible to make this judgement? By recording the height of everyone it is possible to start to produce a picture of people as a whole. Such terms as minimum, maximum, and mean give an indication of the distribution of heights. The science used to collect and examine data in this way is known as epidemiology. Epidemiology is defined as: . . . The orderly study of diseases and conditions where the group and not the individual is the unit of interest. . . . Mausner and Kramer ( 1985 ) state that epidemiology is concerned with the frequencies of illnesses and injuries in groups of people as well as the factors that influence their distribution. By investigating differences between subgroups of the population and their exposure to certain factors it is possible to identify causal factors and consequently to develop programmes to alleviate the problems. The critical issue is that knowledge is gained by studying patterns in groups as opposed to concentrating solely on the individual. This chapter gives an overview of the uses of epidemiology in dentistry and describes the main principles of this subject. Epidemiology in dentistry operates in three broad fields. These are: . . . 1 the measurement of dental disease among groups within the population in order to understand factors that influence the distribution; . . . . . . 2 identification of factors that cause conditions; . . . . . . 3 evaluation of effectiveness of new materials and treatment in clinical trials and assessment of needs and requirements for dental services within the community. . . . Undertaking epidemiological investigations requires a series of standards and procedures; measures must be made to an agreed common standard, in a methodological manner, and, when necessary, using an appropriate random sample.

From individual to collective vigilance in wild boar (Sus scrofa)

1992 ◽  
Vol 70 (8) ◽  
pp. 1632-1635 ◽  
Author(s):  
Pierre-Yves Quenette ◽  
Jean-François Gerard
Keyword(s):  
Wild Boar ◽  
Group Size ◽  
Sus Scrofa ◽  
Functional Approach ◽  
The Other ◽  
Motor Variability ◽  
Proximate Causation ◽  
Vigilance Behaviour ◽  
The Mean ◽  
The Individual

Vigilance behaviour of captive wild boars at feeding points was investigated using films. Results show that individual vigilance decreased with increasing group size, especially between solitary individuals and groups of 2. Moreover, the collective vigilance was, whatever the group size, below the individual vigilance in solitary animals. The study of the motor variability of vigilance behaviour allows three types of movement to be distinguished. The mean durations of each type vary largely, but are almost constant whatever the group size. On the other hand, the relative proportions of the vigilance acts change according to group size. Although previous studies of vigilance are in keeping with the functional approach of behaviour, these data are interpreted in terms of proximate causation. A mechanism based on allelomimesis is proposed to explain the results.

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