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The evolvement of data intensive applications in the cloud computing platform increased the burden of the cloud and resulted in the violation of the service level agreement (SLA). Moreover, the single cloud scenario offers no flexibility to switch between cloud service providers (CPs), leading to limited resource utilization and slower execution. To resolve these issues, this article introduces a hierarchical framework for task scheduling in a federated cloud scenario with multiple datacenters (DCs). The dynamic tasks with different resource requirements are considered to arrive at the federated cloud environment for successful execution. Initially, the task agent receives the tasks and clusters them using the proposed enhanced density peaks clustering (EDPC) algorithm. The proposed clustering algorithm clusters the tasks based on their resource requirements and results in two clusters such as CPU demanding tasks and I/O demanding tasks. After clustering, the tasks are sent to the federation layer, where the scheduling decisions are taken for the tasks. The federated cloud manager (FCM) within the cloud service provider (CP) communicates with the available DCs regarding resource availability. If the resources cannot satisfy the needs, they extend communication with the neighboring FCMs within the federation to complete the execution of tasks. After acquiring the availability status of the entire federation, the FCM executes the African vultures optimization algorithm (AVOA) based task scheduling framework to make the scheduling decision. The performance of the proposed model is evaluated using the GWT T-12 Bit Brains dataset by implementation in the CloudSim tool. The proposed model proved its efficacy over the compared metaheuristics in different metrics. [ABSTRACT FROM AUTHOR]

Purpose: Patients with ovarian cancer and their spousal caregivers report similarities in health-related quality of life (HRQoL) and experiences throughout the cancer process. Previous research has reflected these shared experiences, demonstrating caregivers' capacity to accurately rate their patient-partner's HRQoL as a proxy. In response, this study examines associations between caregivers' perceptions of their patient-partner's HRQoL and their own caregiving responsibilities, consequences to well-being, and desired assistance from the healthcare system. This study will be beneficial when developing supports to assist caregivers throughout the cancer journey. Methods: Using a cross-sectional survey design, spousal caregivers (N = 82) of patients with ovarian cancer completed measures on perceived patient HRQoL and caregiver experiences. Correlation analyses determined medical and sociodemographic covariates. A multivariate multiple regression was conducted using four proxy HRQoL functioning subscales and three factors of reported experiences as caregivers in cancer. Post-hoc univariate regression analyses were run on significant factors to assess the associations that exist. Results: Caregiver-perceived patient physical functioning was significantly associated with more caregiving tasks after controlling for education, age, and stage of ovarian cancer, but no other HRQoL functioning scale (i.e., role, emotional, social) was associated with caregiver experiences. Conclusion: The study provides a unique perspective into the caregiver experience by attending to interpersonal factors in relation to caregiver experiences. Results may be able to guide interventions aimed at supporting caregivers through the cancer process by offering more assistance with tasks as their partner's physical condition worsens. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to create a model of patient-centered outcomes with respect to self-management tasks and skills of patients with a tracheostomy in their home setting. Methods: A scoping review using four search engines was undertaken (Medline, CINAHL, PsycINFO, Cochrane Library) to identify studies relevant to this issue and published since 2000. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statements for Scoping Reviews (PRISMA-ScR), the Joanna Briggs Institute (JBI) approach of conducting and reporting a scoping review, and the Participants, Concept, Context (PCC) scheme were employed. The following elements of the framework synthesis study data were screened, and presented based on the self-management model of Lorig and Holman. Results: 34 publications from 17 countries met the criteria for study inclusion: 24 quantitative, 8 qualitative and 2 mixed methods designs. Regarding the dimensions of self-management, 28 articles reported on "managing the therapeutic regimen", 27 articles discussed "managing role and behavior changes", and 16 articles explored "managing emotions". A model of self-management of patients with tracheostomy was developed, which placed the patient in the center, since it is this individual who is completing the tasks and carrying out his or her skill sets. Conclusion: This scoping review represents the first comprehensive overview and modeling of the complex self-management tasks and skills required of patients with tracheostomy in their home setting. The theoretical model can serve as a cornerstone for empirical intervention studies to better support this patient-centered outcome for this population in the future. [ABSTRACT FROM AUTHOR]

The classification of development tasks for innovative industrial clusters in regional innovation systems is considered. The importance of such clusters in regional economic development is established. A classification of development tasks in four planes is proposed. Each plane corresponds to a different direction of development. The benefits of cluster development are identified at the level of the cluster constituent, the cluster, and the region. [ABSTRACT FROM AUTHOR]

How does a firm's foreign direct investment (FDI) in a low-wage country change its onshore task demand in a high-wage country? Is the shift more intensive for jobs that the literature has designated offshorable? We address these questions using a matched difference-in-differences (DiD) approach with data on German firms that have similar propensities to conduct FDI in the Czech Republic. Our novel matching procedure draws on post-lasso logit estimates and shows that high task intensities of managing, administration, and labor legislation play a major role in firms' engagement in international expansion. The outcomes of the DiD estimation show that after acquiring a foreign affiliate, multinational enterprises (MNEs) increase the intensities of their activities typical of headquarters such as managing, analyzing, and negotiating relative to the corresponding task intensities among non-MNEs. We also find sector-specific decreases, such as a reduction in typical production tasks (monitoring, producing, measuring) in manufacturing MNEs or typical service tasks (informing, medical, repairing) in service MNEs. [ABSTRACT FROM AUTHOR]

The most important step in preparing for the introduction of failure mode and effects analysis (FMEA) at a production enterprise is to create a team of experts. The requirements in terms of skills for FMEA team members are described in detail. Professional requirements for the team in terms of design analysis (DFMEA) and the analysis of production processes (PFMEA) are outlined. Principles for effective training of the experts are discussed. [ABSTRACT FROM AUTHOR]

This paper analyzes the labor market effects of offshoring in a high-wage home country and how these effects crucially depend on (1) Job complexity and (2) The characteristics of the destination country. It thereby links several sources: rich administrative data on individuals and plants in the German manufacturing industries, information on a job's task bundle, and the evolution of imported inputs from low- or high-wage destinations, which are represented by Eastern and Western Europe, respectively. Offshoring to these origins has opposing effects on German wages with respect to the relative task complexity of jobs: While offshoring to the West puts pressure on the wages of complex jobs and increases the wages of simple jobs, offshoring to the East entails the opposite effect. The overall effect adds up to a 4.2 percent increase in wages for jobs with high complexity, while low-complexity jobs see a 3.9 percent decrease in wages. [ABSTRACT FROM AUTHOR]

We study how the tasks conducted on the job relate to measures of cognitive skills using data from 18 countries participating in the Programme for the International Assessment of Adult Competences (PIAAC) and from 13 countries that also participate in the International Adult Literacy Study (IALS). We document two main findings. Firstly, individual-fixed effect models suggest that low-educated workers specializing in a particular set of basic tasks -say, in numeric relative to reading or ICT tasks- obtain 10% of one standard deviation higher scores in the domain of the PIAAC assessment most related to those tasks than in the rest -say, numeracy relative to literacy or problem-solving scores. Secondly, a synthetic cohort analysis using repeated literacy assessments in IALS and PIAAC indicates that, among the low-educated, long-run increases in the reading task component of jobs correlate positively with increases in cohort-level literacy scores. The results are stronger among low-skilled workers with less working experience or females -i.e., the set of workers who have had less time to sort in the labor market. An interpretation of our findings is that tasks conducted on the job help in building human capital but are imperfect substitutes of formal schooling. [ABSTRACT FROM AUTHOR]

The advent of artificial intelligence is changing the task allocation of workers and machines in firms' production processes with potentially wide ranging effects on workers and firms. We develop an agent-based simulation framework to investigate the consequences of different types of automation for industry output, the wage distribution, the labor share, and industry dynamics. It is shown how the competitiveness of markets, in particular barriers to entry, changes the effects that automation has on various outcome variables, and to which extent heterogeneous workers with distinct general skill endowments and heterogeneous firms featuring distinct wage offer rules affect the channels via which automation changes market outcomes. [ABSTRACT FROM AUTHOR]

Whether team task conflict is beneficial or harmful to team innovation has long been controversial, and empirical studies on the team task conflict–team innovation relationship were inconsistent. Drawing on the contingency model of team innovation, the current study examined how team task conflict interacts with two types of team supportive climates, namely team support for innovation (TSFI) and team psychological safety (TPS), in predicting team innovation via team information elaboration. We tested our hypotheses using multi-source and lagged data collected from 361 employees working in 98 research and development teams. As expected, team information elaboration mediated the interaction effects between team task conflict and team supportive climates on team innovation. In particular, team task conflict had a positive indirect effect on team innovation via team information elaboration when TSFI or TPS was high. However, such indirect effect was negative when TSFI was low and was not significant when TPS was low. Residualized relative weight analysis comparing the moderation effects further suggests that TFSI and TPS are equally important team climates in activating the beneficial effect of team task conflict. Theoretical and practical implications are discussed. [ABSTRACT FROM AUTHOR]

Purpose: Prolonged low-frequency force depression (PLFFD) occurs following both dynamic and static fatiguing tasks, but it has been assessed predominately using measures of isometric torque. However, it is unknown whether PLFFD induced during dynamic tasks is adequately characterized by isometric torque, which excludes velocity and power. The purpose of this study was to compare PLFFD assessed using isometric torque and isotonic power following a concentric fatiguing task. Methods: Young (18–31 years) males (n = 9) and females (n = 4) performed isotonic plantar flexion contractions until a ~ 75% reduction in peak power. Isotonic and isometric contractions were electrically evoked at 10 Hz and 50 Hz via tibial nerve stimulation. Isotonic and isometric PLFFD was assessed as the ratio of 10 to 50 Hz for power and torque, respectively. Recovery was assessed immediately, and at 2.5, 5, 10, 20, and 30 min after task termination. Results: Relative to baseline, 10:50 Hz ratio assessed using isotonic power was reduced more than isometric torque (30 min 41 ± 17 vs. 25 ± 12% reduction, p = 0.001); however, both contraction modes displayed similar trajectories throughout recovery (p = 0.906). The larger reduction in isotonic 10:50 Hz ratio was due to greater impairments in 10 Hz power compared to 10 Hz isometric torque (30 min 38 ± 20 vs. 21 ± 11% reduction, p < 0.001). Conclusion: The similar trajectories of 10:50 Hz ratios throughout recovery indicate that PLFFD can be adequately characterized using either isometric torque or isotonic power. [ABSTRACT FROM AUTHOR]

Few-shot segmentation aims to learn a segmentation model that can be generalized to novel classes with only a few training images. In this paper, we propose a Cross-Reference and Local–Global Conditional Networks (CRCNet) for few-shot segmentation. Unlike previous works that only predict the query image's mask, our proposed model concurrently makes predictions for both the support image and the query image. Our network can better find the co-occurrent objects in the two images with a cross-reference mechanism, thus helping the few-shot segmentation task. To further improve feature comparison, we develop a local-global conditional module to capture both global and local relations. We also develop a mask refinement module to refine the prediction of the foreground regions recurrently. Experiments on the PASCAL VOC 2012, MS COCO, and FSS-1000 datasets show that our network achieves new state-of-the-art performance. [ABSTRACT FROM AUTHOR]

Graphs offer a natural way to formulate Multiple Object Tracking (MOT) and Multiple Object Tracking and Segmentation (MOTS) within the tracking-by-detection paradigm. However, they also introduce a major challenge for learning methods, as defining a model that can operate on such structured domain is not trivial. In this work, we exploit the classical network flow formulation of MOT to define a fully differentiable framework based on Message Passing Networks. By operating directly on the graph domain, our method can reason globally over an entire set of detections and exploit contextual features. It then jointly predicts both final solutions for the data association problem and segmentation masks for all objects in the scene while exploiting synergies between the two tasks. We achieve state-of-the-art results for both tracking and segmentation in several publicly available datasets. Our code is available at https://github.com/ocetintas/MPNTrackSeg [ABSTRACT FROM AUTHOR]

Autonomous multi-robot optical inspection systems are increasingly applied for obtaining inline measurements in process monitoring and quality control. Numerous methods for path planning and robotic coordination have been developed for static and dynamic environments and applied to different fields. However, these approaches may not work for the autonomous multi-robot optical inspection system due to fast computation requirements of inline optimization, unique characteristics on robotic end-effector orientations, and complex large-scale free-form product surfaces. This paper proposes a novel task allocation methodology for coordinated motion planning of multi-robot inspection. Specifically, (1) a local robust inspection task allocation is proposed to achieve efficient and well-balanced measurement assignment among robots; (2) collision-free path planning and coordinated motion planning are developed via dynamic searching in robotic coordinate space and perturbation of probe poses or local paths in the conflicting robots. A case study shows that the proposed approach can mitigate the risk of collisions between robots and environments, resolve conflicts among robots, and reduce the inspection cycle time significantly and consistently. [ABSTRACT FROM AUTHOR]

In cloud computing, task scheduling and resource allocation are the two core issues of the IaaS layer. Efficient task scheduling algorithm can improve the matching efficiency between tasks and resources. In this paper, an enhanced heterogeneous earliest finish time based on rule (EHEFT-R) task scheduling algorithm is proposed to optimize task execution efficiency, quality of service (QoS) and energy consumption. In EHEFT-R, ordering rules based on priority constraints are used to optimize the quality of the initial solution, and the enhanced heterogeneous earliest finish time (HEFT) algorithm is used to ensure the global performance of the solution space. Simulation experiments verify the effectiveness and superiority of EHEFT-R. [ABSTRACT FROM AUTHOR]

In crowd sensing systems, mobile users provide requesters with access to the resources of their mobile devices, such as the core processor, memory, and camera, to execute tasks in return for monetary payment. Existing works consider the offline setting where information about mobile users and requesters is publicly known. However, this assumption does not hold for crowd sensing systems in the real world, where mobile users and requesters can arrive and leave at any time. We address the problem of online task allocation and pricing in crowd sensing systems without making any assumptions about the future information of mobile users and requesters. We formulate this problem in an auction-based online setting and propose a feasible and online double auction mechanism. The proposed online mechanism considers one-to-many mapping, which permits multiple mobile devices to work together to complete the same task at different times in order to improve resource utilization. In addition, we show that the proposed mechanism maintains individual rationality, budget-balance, and computational tractability. Furthermore, we analyze the approximation ratio of the proposed approximation algorithm. The experimental results show that a user cannot increase her utility by untruthful declaration, and the proposed mechanism brings more economic benefit for the auctioneer and stimulates users to join the system. [ABSTRACT FROM AUTHOR]

Even though impaired visuospatial abilities can negatively affect daily functioning, there are very few training programs that attempt to improve visuospatial abilities. The purpose of this study was to examine if a single training session with a computerized version of the Corsi Block Tapping Task could improve mental rotation skills. Fifty-three young adults were assigned to one of two groups: (1) control group (mean age = 21.4; 10 females), who had 20 min of rest after their baseline assessment, or (2) training group (mean age = 21.5; 17 females), who had 20 min of training on the Corsi Block Tapping Task after their baseline assessment. The primary outcome was reaction time on a computer-based mental rotation task, and it was assessed both before and after the rest or training. There was a significant interaction between time (pre vs. post) and group (control vs. training) on mental rotation performance (p = 0.04), with the training group performing on average 124 ms faster on accurate trials than the control group at post-test. This preliminary study suggested that improving mental rotation may be feasible through targeted cognitive training. Future studies will consider multiple sessions of Corsi Block Tapping Task training to maximize training benefits (i.e., dose–response), as well as longer term retention in cognitively intact and impaired individuals. [ABSTRACT FROM AUTHOR]

Various behavioural tasks measure response inhibition encompassing the ability to cancel unwanted actions, evaluated via stop signal reaction time (SSRT). It is unclear whether SSRT is an unchangeable inherent measure of inhibitory network integrity or whether it can improve with repetition. The current study explored if and how SSRT changed over two sessions for the Anticipatory Response Inhibition Task (ARIT), and how this compared with the Stop Signal Task (SST). Forty-four participants repeated the ARIT and SST over two sessions. SSRT and its constituent measures (Go trial reaction time, stop signal delay) were calculated. SSRT reflecting non-selective response inhibition was consistent between sessions in the ARIT and SST (both p > 0.293). Reaction time and stop signal delay also remained stable across sessions in the ARIT (all p > 0.063), whereas in the SST, reaction time (p = 0.013) and stop signal delay (p = 0.009) increased. SSRT reflecting behaviourally selective stopping on the ARIT improved (p < 0.001) over two sessions, which was underpinned by changes to reaction time (p < 0.001) and stop signal delay (p < 0.001). Overall, the maximal efficiency of non-selective inhibition remained stable across two sessions in the ARIT. Results of the SST confirmed that non-selective inhibition can, however, be affected by more than inhibitory network integrity. Behaviourally selective stopping on the ARIT changed across sessions, suggesting the sequential neural process captured by the SSRT occurred more quickly in session two. These findings have implications for future studies that necessitate behavioural measures over multiple sessions. [ABSTRACT FROM AUTHOR]

Deficits in spatial memory, orientation, and navigation are often early or neglected signs of degenerative and vestibular neurological disorders. A simple and reliable bedside test of these functions would be extremely relevant for diagnostic routine. Pointing at targets in the 3D environment is a basic well-trained common sensorimotor ability that provides a suitable measure. We here describe a smartphone-based pointing device using the built-in inertial sensors for analysis of pointing performance in azimuth and polar spatial coordinates. Interpretation of the vectors measured in this way is not trivial, since the individuals tested may use at least two different strategies: first, they may perform the task in an egocentric eye-based reference system by aligning the fingertip with the target retinotopically or second, by aligning the stretched arm and the index finger with the visual line of sight in allocentric world-based coordinates similar to using a rifle. The two strategies result in considerable differences of target coordinates. A pilot test with a further developed design of the device and an app for a standardized bedside utilization in five healthy volunteers revealed an overall mean deviation of less than 5° between the measured and the true coordinates. Future investigations of neurological patients comparing their performance before and after changes in body position (chair rotation) may allow differentiation of distinct orientational deficits in peripheral (vestibulopathy) or central (hippocampal or cortical) disorders. [ABSTRACT FROM AUTHOR]

Due to the argued benefits of passenger comfort, cost savings, and road safety, the bus sector is showing increasing interest in advanced driver-assistance systems (ADAS). Despite this growth of interest in ADAS and the fact that work tasks are sometimes complicated (especially docking at bus-stops which may occur several hundred times per shift), there has been little research into ADAS in buses. Therefore, the aim of this study was to develop further knowledge of how professional bus drivers experience and accept an ADAS which can help them dock at bus-stops. The study was conducted on a public route in an industrial area with five different bus-stops. Ten professional bus drivers got to use a narrow navigation system (NNS) that could dock automatically at bus-stops. The participants' experience and acceptance were investigated using objective as well as subjective data (during and after the test-drive) and data were collected using interviews, questionnaires, and video recordings. The participants indicated high levels of trust in and acceptance of the NNS and felt that it had multiple benefits in terms of cognitive and physical ergonomics, safety, and comfort. However, the relatively slow docking process (which was deemed comfortable) was also expected to negatively affect, e.g., timetabling, possibly resulting in high stress levels. Therefore, when investigating users' acceptance of ADAS in a work context, it is important to consider acceptance in terms of the operation, use, and work system levels and how those levels interact and affect each other. [ABSTRACT FROM AUTHOR]

Semantic segmentation of parts of objects is a marginally explored and challenging task in which multiple instances of objects and multiple parts within those objects must be recognized in an image. We introduce a novel approach (GMENet) for this task combining object-level context conditioning, part-level spatial relationships, and shape contour information. The first target is achieved by introducing a class-conditioning module that enforces class-level semantics when learning the part-level ones. Thus, intermediate-level features carry object-level prior to the decoding stage. To tackle part-level ambiguity and spatial relationships among parts we exploit an adjacency graph-based module that aims at matching the spatial relationships between parts in the ground truth and predicted maps. Last, we introduce an additional module to further leverage edges localization. Besides testing our framework on the already used Pascal-Part-58 and Pascal-Person-Part benchmarks, we further introduce two novel benchmarks for large-scale part parsing, i.e., a more challenging version of Pascal-Part with 108 classes and the ADE20K-Part benchmark with 544 parts. GMENet achieves state-of-the-art results in all the considered tasks and furthermore allows to improve object-level segmentation accuracy. [ABSTRACT FROM AUTHOR]

This paper builds on our previous research and investigates how students' fractional competence and reasoning can provide clear evidence of non-symbolic algebraic thinking and its progressive transition towards fully generalised algebraic thinking. In a large-scale study, 470 primary students completed a written paper and pencil test. This included three reverse fraction tasks which required students to find an unknown whole when presented with a quantity representing a fraction of that whole. Seventeen students from one participating primary school undertook a semi-structured interview which included reverse fraction tasks, similar to those on the written test, but with progressive levels of abstraction, starting with particular instances and becoming more generalised. Two important products of the study are the Classification Framework for Reverse Fraction Tasks and the Emerging Algebraic Reasoning Framework. The interview results highlight two critical transition points for the emergence of students' algebraic reasoning. The first is the ability to transition from additive strategies to multiplicative strategies to solve reverse fraction problems. Students reliant on diagrams and additive strategies struggled to solve more generalised tasks that required multiplicative rather than additive strategies. The second transition is the shift from multiplicative thinking to algebraic reasoning where students could generalise their multiplicative knowledge to deal with any quantity represented in a reverse fraction task. [ABSTRACT FROM AUTHOR]

A key aspect of young children's development of algebraic reasoning is the process of visualising and identifying structures to both abstract and generalise. There has been a growing body of research focused on how students form generalisations, this article adds to the existing body of research by examining how young culturally diverse students identify mathematical structures in contextual growing patterns and the teaching and learning actions that assist them to generalise. Data were collected from one classroom of 29 Year Two (6 years old) students in a low socio-economic school in New Zealand. Results from the analysis of lessons related to two tasks showed that the contextual tasks led students to notice different mathematical structures. Specific pedagogical actions were used to facilitate students' engagement with the growing patterns. These included positioning students to engage with different representations (pictorial and numerical, tabular, and natural language) to represent thinking, the use of classroom discussions, noticing and responding to student thinking, and pressing students to find far terms. The findings highlight that both the contextual patterning tasks and teacher actions supported the young students to develop a range of sophisticated generalisations related to the underlying mathematical structure and functional relationships of the growing patterns. [ABSTRACT FROM AUTHOR]

During reaching and grasping movements tactile processing is typically suppressed. However, during a reception or catching task, the object can still be acquired but without suppressive processes related to movement execution. Rather, tactile information may be facilitated as the object approaches in anticipation of object contact and the utilization of tactile feedback. Therefore, the current study investigated tactile processing during a reception task. Participants sat with their upper limb still as an object travelled to and contacted their fingers. At different points along the object's trajectory and prior to contact, participants were asked to detect tactile stimuli delivered to their index finger. To understand if the expectation of object contact contributed to any modulation in tactile processing, the object stopped prematurely on 20% of trials. Compared to a pre-object movement baseline, relative perceptual thresholds were decreased throughout the object's trajectory, and even when the object stopped prematurely. Further, there was no evidence for modulation when the stimulus was presented shortly before object contact. The former results suggest that tactile processing is facilitated as an object approaches an individual's hand. As well, we purport that the expectation of tactile feedback drives this modulation. Finally, the latter results suggest that peripheral masking may have reduced/abolished any facilitation. [ABSTRACT FROM AUTHOR]

Object affordance detection aims to identify, locate and segment the functional regions of objects, so that robots can understand and manipulate objects like humans. The affordance detection task has two main challenges: (1) Due to the need to provide accurate positioning information for the robot to manipulate objects, the affordance segmentation results are required to have high boundary quality. (2) Different kinds of objects have significant differences in appearances, but may have the same affordance. Correspondingly, parts with the same appearance may have different affordances. The existing methods regard affordance detection as an image segmentation problem, without focusing on the boundary quality of detection results. In addition, most of the existing methods do not consider the potential relationship between object categories and object affordances. Aiming at the above problems, we propose a boundary-preserving network (BPN) to provide affordance masks with better boundary quality for robots to manipulate objects. Our framework contains three new components: the IoU (Intersection-over-Union) branch, the affordance boundary branch and the relationship attention module. The IoU branch is used to predict the IoU score of each object bounding box. The affordance boundary branch is used to guide the network to learn the boundary features of objects. The relationship attention module is used to enhance the feature representation capability of the network by exploring the potential relationship between object categories and object affordances. Experiments show that our method is helpful to improve the boundary quality of the predicted affordance masks. On the IIT-AFF dataset, the performance of the proposed BPN is 2.32% (F-score) and 2.89% (F-score) higher than that of the strong baseline in terms of affordance masks and the boundaries of affordance masks, respectively. Furthermore, the real-world robot manipulation experiments show that the proposed BPN can provide accurate affordance information for robots to manipulate objects. [ABSTRACT FROM AUTHOR]

The grating orientation discrimination task (GOT) is a sensitive and reliable measure of tactile spatial resolution, or acuity. We used the GOT in three experiments to investigate the effects of hand posture and hand visibility on spatial acuity. Participant sex and experimental design were also manipulated. Healthy adult participants received brief touches to their index fingertips of grated, domed objects. Their task was to decide whether the gratings ran 'along' or 'across' their finger. Measures of the smallest grating width for which participants could reliably discriminate between orientations were recorded as threshold. Experiment 1 evaluated the effect of two- versus one-interval discrimination, hand used and participant sex. Experiments 2 and 3 evaluated the effects of hand visibility (visible or covered) and hand posture (in front or to the side). Females were better than males; the two-interval task resulted in lower thresholds than the one-interval task; and left and right hand thresholds were not significantly different. Most importantly, while hand visibility did not have a significant effect on the task, thresholds were affected by hand posture—worse when the hand was oriented to the side of the body than in front. These results replicate previously reported effects of sex (or finger size), but failed to replicate the so-called 'visual enhancement of touch' (VET) effect. We also report a meta-analysis of 27 VET studies, finding a significant effect of 'non-informative' vision on tactile perception. Our novel finding is that hand posture affects tactile acuity. [ABSTRACT FROM AUTHOR]

This study expands on Keiser and Arthur's (2021) meta-analysis of the after-action review (AAR), or debrief, by examining six additional task and training characteristics that contribute to or attenuate its effectiveness. The findings based on a bare-bones meta-analysis of results from 83 studies (134 ds [955 teams; 4,684 individuals]) indicate that the effectiveness of the AAR (overall d = 0.92) does indeed vary across the pertinent characteristics. The primary impact of this study pertains to the practical implementation of AARs; notably, the findings indicate that the AAR is particularly effective in task environments that are characterized by a combination of high complexity and ambiguity in terms of offering no intrinsic feedback. The types of tasks—often project and decision-making—that more commonly entail these characteristics are frequently used in industries that do not traditionally use the AAR. The results also suggest that more recent variants of the AAR (i.e., a reaction phase, a canned performance review) do not meaningfully add to its effectiveness. These findings are combined with those from prior meta-analyses to derive 11 empirically-based practical guidelines for the use of AARs. In sum, this study highlights the complexity of the AAR that results from the independent and interdependent influence among various components and characteristics, the examination of the effects of novel and ostensibly distinct variants or approaches to AARs, and the extension of AARs to tasks and contexts in which they are less commonly used. [ABSTRACT FROM AUTHOR]

Based on the stressor-detachment model, previous research has assumed that work-related ICT use in the evening impairs psychological detachment. However, since most of the studies to date have assessed cross-sectional relationships, little is known about the actual direction of effects. In this 5-day diary study, we implemented a day-level longitudinal model to shed light on the causal relationships between work-related ICT use, detachment, and task progress (N = 340 employees, N = 1289 day-level cases). We also investigated the role of unfinished work tasks because we assumed, based on boundary theory, that they are a driving force leading to impaired detachment and work-related ICT use in the evening. Contrary to current research consensus but in line with our expectations, we found that low psychological detachment increased work-related ICT use and task progress. We found no evidence for reversed lagged effects. These results applied both to planned and unplanned ICT use. Furthermore, our results support the notion that unfinished work tasks precede ICT use and detachment. Thus, our findings suggest that work-related ICT use should not be treated as a stressor in its own right in the stressor-detachment model. Instead, it needs to be investigated as a behavioral outcome that employees engage in when they cannot detach from work. [ABSTRACT FROM AUTHOR]

We investigated the relationship between holistic processing and face processing using a latent variables approach. Three versions of the composite paradigm were used to measure holistic processing: Vanderbilt Holistic Face Processing Test, a sequential composite matching task, and a simultaneous composite matching task. Three tasks were used to measure face perception and face memory abilities respectively. We had three pairs of tasks such that within each pair (of memory and perception task), the stimuli involved, the requirement for matching across viewpoints, etc., are the same, such that the only difference is whether perception or memory is taxed. There were no significant correlations between the different versions of the composite task. We discovered no evidence to support a distinction between face perception and face memory, suggesting the existence of a general face processing factor. Finally, there was no evidence that holistic processing (as captured by either of the three composite tasks) is predictive of better face processing per se, casting doubts on the role of holistic processing in differentiating different levels of efficiency in face processing. [ABSTRACT FROM AUTHOR]

At least three processes determine whether information we encounter is attended to or ignored. First, attentional capture occurs when attention is drawn automatically by "bottom up" processes, to distinctive, salient, rewarding, or unexpected stimuli when they enter our sensory field. Second, "top down" attentional control can direct cognitive processing towards goal-relevant targets. Third, selection history, operates through repeated exposure to a stimulus, particularly when associated with reward. Attentional control is measured using tasks that require subjects to selectively attend to goal-relevant stimuli in the face of distractions. In the Eriksen flanker task, human participants report which direction a centrally placed arrow is facing, while ignoring "flanking" arrows that may point in the opposite direction. Attentional control is evident to the extent that performance reflects only the direction of the central arrow. We describe four experiments in which we systematically assessed attentional control in rhesus monkeys using a flanker task. In Experiment 1, monkeys responded according to the identity of a central target, and accuracy and latency varied systematically with manipulations of flanking stimuli, validating our adaptation of the Eriksen flanker task. We then tested for converging evidence of attentional control across three experiments in which flanker performance was modulated by the distance separating targets from flankers (Experiment 2), luminance differences (Experiment 3), and differences in associative value (Experiment 4). The approach described is a new and reliable measure of attentional control in rhesus monkeys that can be applied to a wide range of situations with freely behaving animals. [ABSTRACT FROM AUTHOR]

The mean estimation task, which explicitly asks observers to estimate the mean feature value of multiple stimuli, is a fundamental paradigm in research areas such as ensemble coding and cue integration. The current study uses computational models to formalize how observers summarize information in mean estimation tasks. We compare model predictions from our Fidelity-based Integration Model (FIM) and other models on their ability to simulate observed patterns in within-trial weight distribution, across-trial information integration, and set-size effects on mean estimation accuracy. Experiments show non-equal weighting within trials in both sequential and simultaneous mean estimation tasks. Observers implicitly overestimated trial means below the global mean and underestimated trial means above the global mean. Mean estimation performance declined and stabilized with increasing set sizes. FIM successfully simulated all observed patterns, while other models failed. FIM's information sampling structure provides a new way to interpret the capacity limit in visual working memory and sub-sampling strategies. As a model framework, FIM offers task-dependent modeling for various ensemble coding paradigms, facilitating research synthesis across different studies in the literature. [ABSTRACT FROM AUTHOR]

Although it is often assumed that spatial attention exists in the form of a unitary focus, the split-attention hypothesis proposes that attention can be simultaneously divided into two spatially noncontiguous positions and that the space in between can be ignored. However, whether split attention occurs directly based on the generation of attentional benefit or whether it requires a gradual divide from a unitary focus over time has not been clarified. In the present study, by using two spatial salient cues to direct the attention allocation of participants, we aimed to investigate whether attention requires time to divide from a unitary focus and whether the appearance time of split attention varies when the task difficulty level increases between experiments. The results showed that attention required time to divide from a unitary focus, and the position between the two cued positions was not excluded by attention when the stimulus-onset asynchrony (SOA) was 60 ms. However, as the task difficulty increased between experiments, the appearance time of split attention was earlier. These findings suggest that the appearance time of split attention has a certain flexibility and can be changed according to the task requirement, thus implying that split attention and unitary attention present some common attention mechanisms and that a split or unitary mode can be flexibly selected for an attention system. [ABSTRACT FROM AUTHOR]

Switching between competing tasks is supported by active inhibition of the preceding task. The level of task stimulus processing at which interference between competing tasks must occur for inhibition to be recruited is still unclear. Here, we investigated whether inhibition is recruited by task conflict occurring at an early or late (semantic) stage of task stimulus processing by dissociating the task stimulus format from its meaning. In two experiments, participants performed three different numerical judgment tasks on numerical stimuli that could be presented as digits or number words (e.g., "6" or "six") in a cued task-switching procedure. The effects of the change of stimulus format for the inhibition of the previous task were investigated and assessed by the N-2 task repetition cost, an index of the extent to which task representations are inhibited. The N-2 task repetition cost observed in the same stimulus format condition disappeared when target stimuli on task N-1 were presented in a different format from stimuli of task N-2 and N. This occurred both when the format changed from digits to number words stimuli (Experiment 1) as well as when it changed from number words to digits stimuli (Experiment 2). Results indicated that task set inhibition is recruited very early during the stimulus processing stage. They also provided evidence that task inhibition is not tied to task preparation processes but operates as a reactive, rather than proactive mechanism of conflict resolution. [ABSTRACT FROM AUTHOR]

The odor span task (OST) is frequently used to assess memory capacity in rodents. Odor stimuli are presented in a large arena and choices of session-novel odors produce food reward. The procedure can be described as an incrementing non-matching-to-sample contingency because on each trial one new stimulus is presented along with one or more previously presented (non-reinforced) comparison odors. An automated version of this task has recently been developed in which odors are presented with an olfactometer in an operant chamber using a successive conditional discrimination procedure. The present study compared the acquisition of matching- vs. non-matching-to-sample versions of the task with six rats tested under each procedure. All six rats trained on the non-matching variation showed rapid acquisition of the discrimination with high rates of responding to odor stimuli when they were session-novel and low rates of responding to subsequent presentations of those odors. However, only three of the six rats trained on the matching variation met acquisition criteria, and two of the three that did acquire the task required extensive training to do so. These results support findings from the OST that rats can differentiate between stimuli that are session-novel and those previously encountered, but also that a matching contingency is more difficult to learn than a non-matching arrangement. These findings parallel differences observed between acquisition of simple matching- and non-matching-to-sample tasks, but accounts such as novelty preference or the oddity preference effect may not be sufficient to explain the present results. [ABSTRACT FROM AUTHOR]

Cloud computing (CC) environment delivers the services requested by the computing devices over the internet. In recent years with the internet epoch, the cloud computing environment is progressed as a significant distributed platform. However, the prime concern associated with the CC environment as task scheduling. Several algorithms were proposed with the objective of optimizing the scheduling process in the CC environment. To fill this gap in this work an integrated Fisher linear discriminant and discrete global swarm-based task scheduling (FLD-DGSTS) method is proposed. Fisher linear discriminant independent task prioritizer algorithm is employed to accurately enhance the quality of solution with minimum makespan and memory. Next, the discrete glowworm swarm optimization process is applied for scheduling cloud user tasks. The fitness function (i.e., CPU cycles, bandwidth, memory, and energy) is measured for addressing optimization and avoiding local convergence. The experimental evaluation of the proposed FLD-DGSTS method is compared to existing task scheduling algorithms with the CloudSim toolkit. The results demonstrate that the FLD-DGSTS method gives better performance with reduces the makespan and memory and ensures high scheduling efficiency than the state-of-the-art task scheduling methods. [ABSTRACT FROM AUTHOR]

Theories of instruction following assume that language contributes to our ability to understand and implement instructions. The two experiments reported here investigated that assumption. Participants (total N = 96) were required to learn a series of novel tasks, with each task consisting of six arbitrary stimulus-response rules. All tasks were preceded by an instruction phase (a visual depiction of the correct stimulus-response rules for each task), during which participants performed a verbal distractor task (articulatory suppression), a non-verbal distractor task (foot tapping) or no distractor task. Additionally, the duration of the instruction phase was varied so that it was either long (60 s) or short (30 s in Experiment 1, or 10 s in Experiment 2). In both experiments participants made more errors when they had performed articulatory suppression during the instruction interval, compared to the foot tapping and no distractor task conditions. Furthermore, Experiment 2 found that this detrimental effect of articulatory suppression was especially pronounced with a very short instruction duration. These findings demonstrate that language plays a crucial role in the encoding of novel task instructions, especially when instructions are encoded under time pressure. [ABSTRACT FROM AUTHOR]

The structure of task representations is widely studied with task-switching procedures in which the experimenter compares performance across predetermined categories of trial transitions (viz., switch costs). This approach has been productive, but relies on experimental assumptions about the relationships among stimulus-response mappings that define a set. Here, we develop a novel method of evaluating structure without relying on such assumptions. Participants responded to centrally presented stimuli and we computed the transitional response times (RTs; changes in RT as a function of specific response sequences) for each response combination. Conventional task-switch analyses revealed costs when the response switched from the left-side to the right or vice versa, but this switch cost was not affected by whether the stimuli belonged to a single category or to two distinct categories. In contrast, the transitional RT analysis provided fine-grained information about relationships among responses and how these relationships were affected by stimulus and response manipulations. Specifically, tasks containing a single stimulus category produced response chains in which neighboring responses had lower transitional RTs, while these chains were broken when two stimulus categories were used. We propose that the transitional RT approach offers a more detailed picture of the underlying task representation that reveals structure not detectable by conventional switch cost measures and does not require a priori assumptions about task organization. [ABSTRACT FROM AUTHOR]

The fog server in a fog computing paradigm extends cloud services to latency-sensitive tasks by employing fog nodes (FNs) near user devices. The resource-constrained FNs face the challenge of meeting stringent deadlines of latency-sensitive tasks. The completion deadline of such tasks becomes critical on preemption. Task preemption is unavoidable in uncertain events, such as FN hostility, overloading, and mobility of the host FN or the user device. Rescheduling the task that is likely to face preemption is a better solution than terminating it. This paper proposes a rescheduling algorithm for the fog server to reschedule preempted tasks to FNs that can serve them to completion within their expected time. The rescheduling algorithm aims to attain a rescheduling list that guarantees the task deadline requirements. The brain-inspired rescheduling decision-making (BIRD) algorithm proposed in this paper uses the actor-critic reinforcement learning method for rescheduling preempted tasks to FNs. It mimics the decision-making model of the human brain to control voluntary motor activity. It guarantees the deadline requirement of the preempted task by ensuring the optimal performance of the FN through load balancing while rescheduling the preempted tasks to FNs. Experimental evaluation shows that the BIRD algorithm offers better FN selection than other scheduling policies such as first come first served (FCFS), greedy task allocation, task allocation based on least laxity, shortest job first (SJF), and earliest deadline first (EDF). [ABSTRACT FROM AUTHOR]

The paper discusses a task preference-based bottleneck assignment problem in which there are n tasks that are divided into three phases in order of preference of performance of various tasks. The assignment problem is balanced with an equal number of agents and tasks. An agent can perform only one task and each task can be accomplished by exactly one agent. Tasks belonging to a particular phase cannot be commenced until the tasks of the previous phase have been completed. Given the performance time of each task by each agent, the aim is to find an assignment of agents to the tasks that minimize the total completion time of all tasks. The total completion time here refers to the sum of the overall completion times of three phases. An iterative algorithm for solving such a task preference-based bottleneck assignment problem is proposed in the paper. The proposed algorithm is validated with the help of theoretical results and numerical illustration. The algorithm has been coded in MATLAB and the computational results show that the algorithm performs well in terms of computing time for finding optimal assignments for task preference-based assignment problems of different sizes. [ABSTRACT FROM AUTHOR]

Supervised learning with the restriction of a few existing training samples is called Few-Shot Learning. FSL is a subarea that puts deep learning performance in a gap, as building robust deep networks requires big training data. Using transfer learning in FSL tasks is an acceptable way to avoid the challenge of building new deep models from scratch. Transfer learning methodology considers borrowing the architecture and parameters of a previously trained model on a large-scale dataset and fine-tuning it for low-data target tasks. But practically, fine-tuning pretrained models in target FSL tasks suffers from overfitting. The few existing samples are not enough to correctly adjust the pretrained model's parameters to provide the best fit for the target task. In this study, we consider mitigating the overfitting problem when applying transfer learning in few-shot Handwritten Character Recognition (HCR) tasks. A data augmentation approach based on Conditional Generative Adversarial Networks is introduced. CGAN is a generative model that can create artificial instances that appear more real and indistinguishable from the original samples. CGAN helps generate extra samples that hold the possible variations of human handwriting instead of applying traditional image transformations. These transformations are low-level, data-independent operations, and only produce augmented samples with limited diversity. The introduced approach was evaluated in fine-tuning the three pretrained models: AlexNet, VGG-16, and GoogleNet. The results show that the samples generated by CGAN can enhance transfer learning performance in few-shot HCR tasks. This is by achieving model fine-tuning with fewer epochs and by increasing the model's F 1 - s c o r e and decreasing the Generalization Error (E test) . [ABSTRACT FROM AUTHOR]

Mobile Crowd Sensing (MCS) involves allocation of sensing tasks associated with an area of interest to a crowd of participants over time. Consequently, the collective amount of time and energy spent on sensing can be quite large. Sparse Mobile Crowd Sensing (Sparse-MCS) aims at reducing this overhead by reducing the number of sensing tasks, which results in obtaining sensed values from only some portions of the area or time. For those portions which are not thus covered, their corresponding values can be inferred from the collected sensed values. Hence, missing data inference is an integral part of Sparse-MCS. This study is divided into two phases: First, we explore the viability of using machine learning, viz., regression for missing data inference in Sparse-MCS. Hence, we explore several representative regression algorithms such as Linear Regression, LASSO, Elastic Net, Ridge, Decision Tree (DT), Random Forest (RF) and KNN. Using two real data-sets, we conclude that some algorithms such as DT and RF exhibit good performance (giving normalized mean absolute error much less than 0.1 most of the time) whereas the rest do not. Moreover, we compare these techniques with a state-of-the-art missing data inference method known as Compressing Sensing with the help of simulation results. Next, we propose a divide-and-conquer polynomial-time algorithm for task reduction which is based on the proposed inference approach. We also present the results of the analysis of the algorithm in terms of: (i) its time complexity, and (ii) lower and upper bounds on task reduction. [ABSTRACT FROM AUTHOR]

Recently, wide-area distributed computing environments have become popular owing to their huge resource capability. In a wide-area distributed computing environment, joint scheduling of tasks and data is the main strategy to improve system performance. However, the geographically distributed diverse resources exhibit high variations, making it challenging to design efficient joint scheduling of tasks and data. To accurately adapt to the dynamic variations of geographically distributed diverse resources and achieve a high system performance, this study proposes a hypergraph-partitioning-based online joint scheduling method. The proposed method constructs a hypergraph of geographically distributed tasks, data, and diverse resources to clearly describe the correlation among the three elements and quantitatively reflect the time cost of different process in the environment. The hypergraph is dynamically updated according to the generated scheduling scheme and the collected information to reflect the dynamic variations of resource states. Then, a hypergraph partition optimization mechanism is proposed to generate efficient joint scheduling schemes, thus reducing the overall completion time in the system. The experimental results indicate that compared with the state-of-the-art joint scheduling methods, the proposed method reduces the overall completion time by up to 25.67% and significantly reduces the task waiting time, although it makes a concession in the data migration time. [ABSTRACT FROM AUTHOR]

Effective human–robot collaboration requires the appropriate allocation of indivisible tasks between humans and robots. A task allocation method that appropriately makes use of the unique capabilities of each agent (either a human or a robot) can improve team performance. This paper presents a novel task allocation method for heterogeneous human–robot teams based on artificial trust from a robot that can learn agent capabilities over time and allocate both existing and novel tasks. Tasks are allocated to the agent that maximizes the expected total reward. The expected total reward incorporates trust in the agent to successfully execute the task as well as the task reward and cost associated with using that agent for that task. Trust in an agent is computed from an artificial trust model, where trust is assessed along a capability dimension by comparing the belief in agent capabilities with the task requirements. An agent's capabilities are represented by a belief distribution and learned using stochastic task outcomes. Our task allocation method was simulated for a human–robot dyad. The team total reward of our artificial trust-based task allocation method outperforms other methods both when the human's capabilities are initially unknown and when the human's capabilities belief distribution has converged to the human's actual capabilities. Our task allocation method enables human–robot teams to maximize their joint performance. [ABSTRACT FROM AUTHOR]

Organizations' hiring processes are increasingly shaped by various digital tools and e-recruitment systems. However, there is little understanding of the recruiters' needs for and expectations towards new systems. This paper investigates recruitment chatbots as an emergent form of e-recruitment, offering a low-threshold channel for recruiter-applicant interaction. The rapid spread of chatbots and the casual nature of their user interfaces raise questions about the perceived benefits, risks, and suitable roles in this sensitive application area. To this end, we conducted 13 semi-structured interviews, including 11 interviews with people who are utilizing recruitment chatbots and two people from companies that are developing recruitment chatbots. The findings provide a qualitative account of their expectations and motivations, early experiences, and perceived opportunities regarding the current and future use of chatbots in recruitment. While chatbots answer the need for attracting new candidates, they have also introduced new challenges and work tasks for the recruiters. The paper offers considerations that can help to redesign recruitment bots from the recruiter's viewpoint. [ABSTRACT FROM AUTHOR]

The perceptual feature of a task such as how a task goal is perceived influences performance and coordination of bimanual actions in neurotypical adults. To assess how bimanual task goal modifies paretic and non-paretic arm performance and bimanual coordination in individuals with stroke affecting left and right hemispheres, 30 participants with hemispheric stroke (15 right-hemisphere damage—RHD); 15 left-hemisphere damage—LHD) and 10 age-matched controls performed reach-to-grasp and pick-up actions under bimanual common-goal (i.e., two physically coupled dowels), bimanual independent-goal (two physically uncoupled dowels), and unimanual conditions. Reach-to-grasp time and peak grasp aperture indexed motor performance, while time lags between peak reach velocities, peak grasp apertures, and peak pick-up velocities of the two hands characterized reach, grasp, and pick-up coordination, respectively. Compared to unimanual actions, bimanual actions significantly slowed non-paretic arm speed to match paretic arm speed, thus affording no benefit to paretic arm performance. Detriments in non-paretic arm performance during bimanual actions was more pronounced in the RHD group. Under common-goal conditions, movements were faster with smaller peak grasp apertures compared to independent-goal conditions for all groups. Compared to controls, individuals with stroke demonstrated poor grasp and pick-up coordination. Of the patient groups, patients with LHD showed more pronounced deficits in grasp coordination between hands. Finally, grasp coordination deficits related to paretic arm motor deficits (upper extremity Fugl–Meyer score) for LHD group, and to Trail-Making Test performance for RHD group. Findings suggest that task goal and distinct clinical deficits influence bimanual performance and coordination in patients with left- and right-hemispheric stroke. [ABSTRACT FROM AUTHOR]

The sustained attention to response task (SART) has been used for over 20 years to assess participants' response times and inability to withhold to No-Go stimuli (commission errors). While there is debate in the literature regarding what causes commissions errors in the SART, there is agreement the SART is subject to a speed-accuracy trade-off (SATO). Researchers have demonstrated that performance on the SART can be influenced by directive instructions to participants to prioritize either speed or accuracy during the task. In the present study, we investigated whether real-time performance feedback and whether feedback emphasis (emphasizing speed or accuracy) affected participants' response times and accuracy. We found performance feedback per se had no impact on performance, but performance emphasis did affect performance, apparently shifting the SATO. This finding provides further evidence that the commission errors in the SART are not indicative of sustained attention or vigilance as those terms are commonly used in the literature, but more likely assess response strategy and motor control (or lack of motor control). These findings have implications for the psychological assessment literature, as well as applied areas where SART findings have been utilized such as shoot/no-shoot decision making. [ABSTRACT FROM AUTHOR]

Body re-sizing illusions can profoundly alter perception of our own body. We investigated whether creating the illusion of a muscled and fit-looking back (Strong) influenced perceived back size, body ownership, and attitudes towards self-capacity during a lifting task. Twenty-four healthy male volunteers performed a standardised lifting task while viewing real-time (delay < 20 ms) video of their own back through a head-mounted display under four different conditions (Normal size, Strong, Reshaped, Large; order randomised). The MIRAGE-mediated reality system was used to modify the shape, size, and morphology of the back. Participants were poor at recognizing the correct appearance of their back, for both implicit (perceived width of shoulders and hips) and explicit (questionnaire) measures of back size. Visual distortions of body shape (Reshaped condition) altered implicit back size measures. However, viewing a muscled back (Strong condition) did not result in a sense of agency or ownership and did not update implicit perception of the back. No conditions improved perceptions/attitudes of self-capacity (perceived back strength, perceived lifting confidence, and perceived back fitness). The results lend support for the importance of the embodiment of bodily changes to induce changes in perception. Further work is warranted to determine whether increased exposure to illusory changes would alter perceptions and attitudes towards self-capacity or whether different mechanisms are involved. [ABSTRACT FROM AUTHOR]

Objective: The length of the hamstring muscles plays an important role in human movements. The aim of the present study was to compare ROM, perceived tightness, and kinetic variables during balance, walking, and running tasks in athletes with and without hamstring tightness. Methods: Thirty healthy female athletes (15 with hamstring tightness and 15 controls) were assessed for ROM, perceived tightness, and kinetic parameters which were obtained by Moticon SCIENCE insoles and Moticon software during single-leg balance, slow/fast walking, and running. Independent t test was used to compare the outcome measures between two groups. Results: The results showed that the control group and the athletes with hamstring tightness are significantly different in regards to ROM, perceived tightness (P = 0.001), the mean center of pressure in the mediolateral direction (MCOPML) (P = 0.01) in single- leg balance, maximum total force of stance phase (MaxTFSP) (P < 0.02) in slow walking, and mean Y end point of gait line (MYEPGL) (P = 0.04) in fast walking. In the running task, none of the study variables were significantly different between the two groups of athletes with and without hamstring tightness. Conclusion: It is recommended to pay more attention to the hamstring flexibility, especially during balance and walking tasks and regaining its normal length should be included in the rehabilitation plans. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to determine if forward step-down task frontal kinematics differ in women with and without patellofemoral pain (PFP). Methods: Cross-sectional study. A total of 32 women were allocated into a healthy control group (CG; n = 16) and to a PFP (n = 16) group. All participants performed two trials with five consecutive forward step-down task (FSD) repetitions each. A video camera, positioned 3 m from the participant's frontal plane, recorded the movement (sampling rate = 30 Hz). All recorded videos were evaluated on Image-J software, and the following outcomes were obtained: delta mean (∆mean, the difference between final and initial positions) and delta peak (∆peak) values for Q-angle (Qϴ), hip and knee frontal plane projection angles, and dynamic valgus index. We compared groups with the Student's t test for independent samples and the Mann–Whitney test. Results: Groups showed similar (p > 0.05) values for Q-angle (∆mean CG = 3.7° ± 2.5°, PFP = 3.2° ± 2.9°; ∆peak CG = 5.8° ± 2.5°, PFP = 5.1° ± 3.1°), hip frontal plane projection angle (∆mean CG = − 13.2° ± 5.4°, PFP = − 10.7° ± 5.3°; ∆peak CG = − 16.9° ± 5.1°, PFP = − 13.7° ± 5.2°), knee frontal plane projection angle (∆mean CG = -3.3° ± 4.5°, PFP = − 3.9° ± 4.5°; ∆peak CG = − 7.9° ± 6.7°, PFP = − 7.6° ± 5.2°) and dynamic valgus index (∆mean CG = − 17.2° ± 8.3°, PFP = − 15.0° ± 9.2°; ∆peak CG = − 19.4° ± 8.1°, PFP = − 17.3° ± 8.7°). Conclusion: The similarity in frontal plane kinematics during FSD between PFP female patients and healthy women suggests that clinicians should be cautious when determining PFP presence in clinical practice with this method and when using it to measure a healthy condition to be achieved during rehabilitation. Trial registration: Study was registered at Clinical Trials (NCT02734030) on Jan 1th of 2016 (retrospectively registered). [ABSTRACT FROM AUTHOR]

Purpose: Fatigue-induced hip-abductor weakness may exacerbate lower-limb misalignments during different dynamic single-leg tasks. We sought to evaluate the effects of fatigue and task on lower limb kinematics and muscle activation and to find associations between measurements obtained in two tasks. Methods: One-group pretest–posttest design. Seventeen healthy adults (9 W) performed the single-leg squat (SLSQUAT) and the single-leg hop (SLHOP) before and after a hip-abduction fatigue protocol. Hip adduction, knee frontal plane projection angle (knee FPPA) and heel inversion displacement were measured during the eccentric phase of the SLSQUAT and the SLHOP, as well as activation of the gluteus medius (GMed), tensor fascia latae (TFL), peroneus longus (PER) and tibialis anterior (TA). Moments and tasks were compared using a repeated-measures two-way ANOVA. Correlation between tasks was evaluated using Spearman's correlation. Results: No differences in kinematics or activation were found between moments. Hip-adduction displacement (P = 0.005), GMed (P = 0.008) and PER (P = 0.037) activation were higher during SLSQUAT, while TA activation was higher during SLHOP (P < 0.001). No differences were found between tasks in knee FPPA and heel inversion. Hip-adduction and knee FPPA were not correlated between tasks, while ankle inversion displacement was positively correlated (rs = 0.524–0.746). Conclusion: Different characteristics of SLSQUAT (slower and deeper) seem to have led to increased hip adduction displacement, GMed, and PER activation and decreased TA activation, likely due to higher balance requirements. However, hip-abductor fatigue didn't influence lower-limb alignment during the tasks. Finally, evaluations should be performed with different single-leg tasks since they don't give the same lower-limb alignment information. [ABSTRACT FROM AUTHOR]