High Performance Group Research Articles

Revealing the brain's adaptability and the transcranial direct current stimulation facilitating effect in inhibitory control by multiscale entropy

The abilities to inhibit impulses and withdraw certain responses are critical for human's survival in a fast-changing environment. These processes happen fast, in a complex manner, and sometimes are difficult to capture with fMRI or mean electrophysiological brain signal alone. Therefore, an alternative measure that can reveal the efficiency of the neural mechanism across multiple timescales is needed for the investigation of these brain functions. The present study employs a new approach to analyzing electroencephalography (EEG) signal: the multiscale entropy (MSE), which groups data points with different timescales to reveal any occurrence of repeated patterns, in order to theoretically quantify the complexity (indicating adaptability and efficiency) of neural systems during the process of inhibitory control. From this MSE perspective, EEG signals of successful stop trials are more complex and information rich than that of unsuccessful stop trials. We further applied transcranial direct current stimulation (tDCS), with anodal electrode over presupplementary motor area (preSMA), to test the relationship between behavioral modification with the complexity of EEG signals. We found that tDCS can further increase the EEG complexity of the frontal lobe. Furthermore, the MSE pattern was found to be different between high and low performers (divided by their stop-signal reaction time), where the high-performing group had higher complexity in smaller scales and less complexity in larger scales in comparison to the low-performing group. In addition, this between-group MSE difference was found to interact with the anodal tDCS, where the increase of MSE in low performers benefitted more from the anodal tDCS. Together, the current study demonstrates that participants who suffer from poor inhibitory control can efficiently improve their performance with 10min of electrical stimulation, and such cognitive improvement can be effectively traced back to the complexity within the EEG signals via MSE analysis, thereby offering a theoretical basis for clinical intervention via tDCS for deficits in inhibitory control.

Humans use social information to adjust their quorum thresholds adaptively in a simulated predator detection experiment

Quorum sensing is used in many biological systems to increase decision accuracy. In quorum sensing, the probability that an individual adopts a behavior is a nonlinear function of the number of other individuals adopting this behavior. From an optimal decision-making perspective, individuals should adjust their quorum threshold to the particulars of the decision problem. Recent work predicts that a key factor here is the quality of social information. In particular, it is predicted that individuals should adjust their quorum thresholds such that it lies in between the average true and false positive rate of the other group members. We here test this prediction with a predator detection experiment. First, human groups observed a group of animals (projected on a white screen) in which a predator was present or absent, and each individual made an independent decision to escape or not. Second, individuals received social information on the decisions of their group members, after which individuals decided again. This social information, however, did not represent their own decisions but consisted of responses that either came from a high-performing group (i.e., many individuals detecting the predator) or from a low-performing group (i.e., few individuals detecting the predator). We found that individuals adaptively adjust their quorum threshold to the quality of the social information: when receiving social information from high-performing groups, individuals employed higher quorum thresholds than when receiving information from low-performing groups. Our study demonstrates that humans can quickly evaluate the quality of publicly available information and adaptively adjust their decision rules.

Tailored instructor feedback leads to more effective virtual-reality laparoscopic training

Laparoscopic novices begin at different performance levels, and studies on tailored training concepts are warranted. The effect of verbal instructor feedback has been investigated with varying results, and its effectiveness in virtual-reality laparoscopic (VRL) simulations still is unclear. This study aimed to determine whether laparoscopic novices with lower initial performance statuses may profit from training with intensive instructor feedback. A prospective, single-blinded study was performed within a week-long curricular course. In this study, 20 medical students performed a complex bimanual maneuver on a VRL simulator. There was a division in performance levels, with a high-performer group (HPG) that received a better median score and a low-performer group (LPG). During the training phase, only the initial LPG received standardized instructor feedback in a one-to-one setting. The final assessment of skills for both groups involved performing the task without feedback at the end of the course. The HPG and LPG showed significantly different initial performance levels according global and categorized (time, economics, error) scores (p < 0.005). This difference disappeared quickly throughout the instructor feedback phase. The final assessment demonstrated that both groups were at the same level of performance. This is the first study to use a tailored training concept with instructor feedback limited to the LPG. The tailored training was effective and economic for the laparoscopic novices and their teachers.

An EAP curriculum design of a content and language integrated learning program for hospitality students in Taiwan

Although there are many pedagogical approaches to teaching English for Academic Purposes (EAP), most share the objective of preparing second language (L2) learners to engage academic study. This paper reports the findings of a case study that explores the approach to the development and features of a content-and-language integrated learning (CLIL) program at a hospitality university in Taiwan. The study describes the theoretical basis of the program and its relation to background and study rationale. Additionally, program development and implementation processes are described. The data were collected during an academic year with a combination of quantitative and qualitative methods including pre- and post- tests, a student questionnaire, field notes, and semi-structured interviews. The research results show that students in the higher performance group (HP) and the lower performance group (LP) have different opinions regarding selected materials, assigned homework to content knowledge learning, English instruction to content knowledge learning, and difficulties with the written tests. The research results are also consistent with previous studies. Practical implications for theory, practice, and future research are also discussed.

An EAP curriculum design of a content and language integrated learning program for hospitality students in Taiwan

Although there are many pedagogical approaches to teaching English for Academic Purposes (EAP), most share the objective of preparing second language (L2) learners to engage academic study. This paper reports the findings of a case study that explores the approach to the development and features of a content-and-language integrated learning (CLIL) program at a hospitality university in Taiwan. The study describes the theoretical basis of the program and its relation to background and study rationale. Additionally, program development and implementation processes are described. The data were collected during an academic year with a combination of quantitative and qualitative methods including pre- and post- tests, a student questionnaire, field notes, and semi-structured interviews. The research results show that students in the higher performance group (HP) and the lower performance group (LP) have different opinions regarding selected materials, assigned homework to content knowledge learning, English instruction to content knowledge learning, and difficulties with the written tests. The research results are also consistent with previous studies. Practical implications for theory, practice, and future research are also discussed.

High Performance Group Merging/Splitting Scheme for Group Key Management

The group merging/splitting event is different to the joining/leaving events in which only a member joins or leaves group, but in the group merging/splitting event two small groups merge together into a group or a group is divided into two independent parts. Rekeying is an importance issue for key management whose target is to guarantee forward security and backward security in case of membership changes, however rekeying efficiency is related to group scale in most existing group key management schemes, so as to those schemes are not suitable to the applications whose rekeying time delay is limited strictly. In particular, multiple members are involved in the group merging/splitting event, thus the rekeying performance becomes a worried problem. In this paper, a high performance group merging/splitting group key management scheme is proposed based on an one-encryption-key multi-decryption-key key protocol, in the proposed scheme each member has an unique decryption key that is corresponding to a common encryption key so as to only the common encryption key is updated when the group merging/splitting event happens, however the secret decryption key still keeps unchanged. In efficiency aspect, since no more than a message on merging/splitting event is sent, at time the network load is reduced since only a group member's key material is enough for other group members to agree a fresh common encryption key. In security aspect, our proposed scheme achieves the key management security requirements including passive security, forward security, backward security and key independence. Therefore, our proposed scheme is suitable to the dynamitic networks that the rekeying time delay is limited strictly such as tolerate delay networks.

The perception of team environment: The relationship between the psychological climate and members’ perceived effort in high-performance groups.

The perception of team environment: The relationship between the psychological climate and members’ perceived effort in high-performance groups.

TNC’s global characteristics and subsidiaries’ performance across European regions

There is significant regional variation in the performance of foreign affiliates in Europe. The aim of this paper is to examine whether differences in their performance can be explained by the characteristics of the corporate group to which they belong. To this end, we develop a novel procedure that allows us to control for the characteristics of the groups to which each subsidiary belongs. These characteristics include the geographical spread of the group, the total number of subsidiaries and complexity of internal hierarchies, and the degree of industry diversification within the group. We also control for the different institutional characteristics at the regional level. We find that subsidiaries belonging to geographically more widely spread but relatively less diversified TNC groups have superior performance. The results also suggest that regions with quality institutions attract affiliates of such high-performance groups.

Compensatory networks to counteract the effects of ageing on language

BackgroundWord-retrieval difficulties are a common consequence of healthy ageing and are associated with a reduction in asymmetrical recruitment of the dorsolateral prefrontal cortex (DLPFC), although the significance of this reduction has not yet been clarified. Using repetitive transcranial magnetic stimulation (rTMS) it has been demonstrated that an asymmetrical involvement of the DLPFC during action naming in young subjects, whereas bilateral involvement was shown in elderly participants. By using rTMS during a naming task in a group of elderly subjects, the aim of the present work was to investigate whether the magnitude of DLPFC asymmetry (left–right rTMS effect) during action naming correlates with task performance, proving the presence of a compensation strategy in some but not all elderly participants. MethodsWe aimed to test if there was a correlation between DLPFC asymmetry (left–right rTMS effect) and naming performance in a group of elderly subjects. ResultsThe results show that rTMS affects action naming differently according to individual naming ability. In particular, the predominance of a left vs. right DLPFC effect was observed only in the low-performing older adults, while an asymmetric reduction was selectively shown in the high-performing group. Interestingly, high-performing older adults also displayed better performances on a phonemic fluency test. ConclusionThe present data suggest that successful ageing is linked to less prefrontal asymmetry, an efficient strategy for counteracting age-related declines in cognitive function.

Comparative study of self efficacy of high & low performance groups of basketball players.

Comparative study of self efficacy of high & low performance groups of basketball players.

High Performance Group IV Photodiodes with Tunable Absorption Edges based on Ternary SiGeSn Alloys

We describe the fabrication of ternary SiGeSn photodiodes and compare the optical and electrical properties of heterostructure devices with the same target compositions (Si: 8-11 %, Sn: 1.7-2.3 %) grown directly on Si(100) and Ge(100) substrates via UHV-CVD reactions of SnD4, Si3H8 and Ge2H6. We show that the quantum efficiency and dark current levels of near lattice-matched alloys grown on Ge wafers are superior to those of comparable Ge devices. The corresponding optoelectronic properties of analogous SiGeSn devices grown on Si are significantly degraded due to the inferior microstructure resulting from the lattice mismatch between the substrate and epilayer. Finally, we also show that minor variations in composition produce significant shifts in the absorption edge of the devices grown on Ge. Collectively the SiGeSn diodes described here exhibit enhanced performance over any previous Sn based group-IV system, underscoring the potential of this 1 eV gap material as versatile candidates for next generations of Si-based optoelectronics, including multijunction photovoltaics.

Speech and pause characteristics in multiple sclerosis: A preliminary study of speakers with high and low neuropsychological test performance

This preliminary study investigated how cognitive-linguistic status in multiple sclerosis (MS) is reflected in two speech tasks (i.e. oral reading, narrative) that differ in cognitive-linguistic demand. Twenty individuals with MS were selected to comprise High and Low performance groups based on clinical tests of executive function and information processing speed and efficiency. Ten healthy controls were included for comparison. Speech samples were audio-recorded and measures of global speech timing were obtained. Results indicated predicted differences in global speech timing (i.e. speech rate and pause characteristics) for speech tasks differing in cognitive-linguistic demand, but the magnitude of these task-related differences was similar for all speaker groups. Findings suggest that assumptions concerning the cognitive-linguistic demands of reading aloud as compared to spontaneous speech may need to be re-considered for individuals with cognitive impairment. Qualitative trends suggest that additional studies investigating the association between cognitive-linguistic and speech motor variables in MS are warranted.

Correlation between academic achievement goal orientation and the performance of Malaysian students in an indian medical school

According to goal orientation theory, achievement goals are defined as the terminal point towards which one's efforts are directed. The four academic achievement goal orientations commonly recognised are mastery, performance approach, performance avoidance and work avoidance. The objective of this study was to understand the goal orientation of second year undergraduate medical students and how this correlates with their academic performance. The study population consisted of 244 second year Bachelor of Medicine and Bachelor of Surgery (MBBS) students of Melaka Manipal Medical College, Manipal campus, Manipal University, India. Students were categorised as high performers and low performers based on their first year university examination marks. Their goal orientations were assessed through a validated questionnaire developed by Was et al. These components were analysed by independent sample t-test and correlated to their first year university examination marks. Confirmatory component factor analysis extracted four factors, which accounted for 40.8% of the total variance in goal orientation. The performance approach goal orientation alone explained 16.7% of the variance followed by mastery (10.8%), performance avoidance (7.7%) and work avoidance (5.7%). The Cronbach's alpha for 19 items, which contributed to internal consistency of the tool, was observed to be 0.635. A strong positive correlation was shown between performance approach, performance avoidance and work avoidance orientations. Of the four goal orientations, only the mean scores in work avoidance orientation differed for low performers and high performers (5.0 vs. 4.3; P = 0.0003). Work avoidance type of goal orientation among the low performer group may account for their lower performance compared with high performer group. This indicates that academic achievement goal orientation may play a role in the performance of undergraduate medical students.

Leaders’ transformational, conflict, and emotion management behaviors in culturally diverse workgroups

PurposePrevious research has shown that diversity is related to both task and relationship conflict in groups. The purpose of this paper is to posit that leadership is an important factor for maintaining high group performance and morale under conditions of conflict. Specifically, the paper argues that leader conflict management, emotion management, and transformational behaviors determine the impact of conflict on group outcomes.Design/methodology/approachData were collected from 585 people in 89 workgroups from eight public service organizations in Australia. The authors used hierarchical regression to test the hypotheses regarding group performance and morale. To test mediation and moderation, the authors followed the procedure outlined by Baron and Kenny. Finally, they used the formulas provided by Preacher, Rucker and Hayes to test for moderated mediation.FindingsResults showed that diversity increased task conflict but was unrelated to relationship conflict. Both task and relationship conflict were negatively associated with group performance and morale, and effective leadership reduced these negative effects to zero. There was also a partial support for the authors’ theoretical model predicting that leadership moderates the indirect effect of diversity on group outcomes occurring through the mediator of conflict.Research limitations/implicationsA greater amount of variation in the diversity of work groups included in the sample would have been useful for overcoming problems of restriction of range, which likely reduced ability to observe an association between diversity and group outcomes. Based on the results, in order to prevent negative emotions from task and relationship conflict from damaging group performance, leaders of diverse groups can act to manage those emotions among their group members. Results from this study implicate conflict management training. While training for conflict management is beyond the scope of this research, further research should examine this issue.Originality/valueThe study extends research in the area of diversity, leadership and group work. In particular, it demonstrates that transformational leadership is an important factor for maintaining high group performance and morale under conditions of conflict. It also offers practical assistance to individuals entrusted with the responsibility of managing culturally diverse workgroups.

Increased local synchronization of resting-state fMRI signal after episodic memory encoding reflects off-line memory consolidation

The changes of spontaneous activity from before and after a memory or learning task had been considered to be related to off-line memory consolidation process in human brain by using resting-state functional connectivity (RSFC) MRI (fMRI). However, RSFC reflects temporal synchronization of timecourses of spatially distinct brain regions and therefore could not determine which specific brain region is involved in the memory consolidation process. Here we used regional homogeneity (ReHo), a method for measuring local synchronization, to link the local spontaneous activity change to off-line episodic memory consolidation. We hypothesized that the spontaneous activity change would be different between people with better memory performance and those with worse performance in memory-related regions. All participants completed two resting-state sessions, that is, before (REST-1) and after (REST-2) an episodic memory encoding task (picture indoor or outdoor judgment). Then, based on the d' of a later surprise memory retrieval test, a high-performance group and a low-performance group, each consisting of 16 participants, were chosen from whole 58 participants. We defined a ReHo ratio, that is, ReHo of REST-2 divided by ReHo of REST-1, as a change induced by memory consolidation. The high-performance group showed a significant higher ReHo ratio than low-performance group in medial temporal lobe (MTL) including parahippocampal and anterior temporal regions. The current results provide neuroimaging evidence supporting that the MTL is involved in off-line memory consolidation of episodic memory. Moreover, this study may provide a paradigm for understanding of episodic memory deficit in Alzheimer's disease.

Expression of the Irisin Precursor FNDC5 in Skeletal Muscle Correlates With Aerobic Exercise Performance in Patients With Heart Failure

Exercise-induced increase in peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) expression has been shown to increase the expression of the fibronectin type III domain containing 5 (FNDC5) gene and thereby its product, irisin, in mice. Given that exercise intolerance is a hallmark characteristic of heart failure (HF), and because PGC-1α and irisin promote exercise benefits in animals, we hypothesized that expression of these genes relates to aerobic performance in patients with HF. Systolic HF (left ventricular ejection fraction ≤40%) patients underwent cardiopulmonary exercise testing to evaluate aerobic performance. High versus low aerobic performance was assessed using oxygen consumption (peak Vo(2) [>14 versus ≤14 mL O(2)·kg(-1)·min(-1)]) and ventilatory efficiency (VE/Vco(2) slope [<34 versus ≥34]). Muscle biopsies of the vastus lateralis and real-time polymerase chain reaction were used to quantify muscle gene expression. Twenty-four patients were studied. FNDC5 (5.7±3.5 versus 3.1±1.2, P<0.05) and PGC-1α (9.9±5.9 versus 4.5±1.9, P<0.01) gene expressions were greater in the high-peak Vo(2) group; correlation between FNDC5 and PGC-1α was significant (r=0.56, P<0.05) only in the high-peak Vo(2) group. Similarly, FNDC5 and PGC-1α gene expression was greater in the high-performance group based on lower VE/Vco(2) slopes (5.8±3.6 versus 3.3±1.4, P<0.05 and 9.7±6 versus 5.3±3.4, P<0.05); FNDC5 also correlated with PGC-1α (r=0.55, P<0.05) only in the low VE/Vco(2) slope group. This is the first study to show that FNDC5 expression relates to functional capacity in a human HF population. Lower FNDC5 expression may underlie reduced aerobic performance in HF patients.

Developing High Performance: Performance Management in the Australian Public Service

This paper provides a new conceptualisation of high performance government for the public sector. Despite the concerted focus on performance management in both the public and private sectors, the performance puzzle remains. In part, we argue, this is because of a failure to recognise the complex interactions across the micro, meso, and macro levels of performance management that characterise such systems in the public sector. We consider the current attention on system-wide 'high performance government', review the existing literature on high performance organisations, and high performance individuals and groups, and then posit a further, and to date missing, level of analysis - high performance governance. The report is part of a multi-year collaborative research project between the Australian National University, the University of Canberra, the University of New South Wales and the Australian Public Service Commission as part of the Ahead of the Game blueprint for reform in the Australian public service.

Multivariate Analysis in the Maximum Strength Performance

This study performed an exploratory analysis of the anthropometrical and morphological muscle variables related to the one-repetition maximum (1RM) performance. In addition, the capacity of these variables to predict the force production was analyzed. 50 active males were submitted to the experimental procedures: vastus lateralis muscle biopsy, quadriceps magnetic resonance imaging, body mass assessment and 1RM test in the leg-press exercise. K-means cluster analysis was performed after obtaining the body mass, sum of the left and right quadriceps muscle cross-sectional area (∑CSA), percentage of the type II fibers and the 1RM performance. The number of clusters was defined a priori and then were labeled as high strength performance (HSP1RM) group and low strength performance (LSP1RM) group. Stepwise multiple regressions were performed by means of body mass, ∑CSA, percentage of the type II fibers and clusters as predictors' variables and 1RM performance as response variable. The clusters mean ± SD were: 292.8 ± 52.1 kg, 84.7 ± 17.9 kg, 19249.7 ± 1645.5 mm(2) and 50.8 ± 7.2% for the HSP1RM and 254.0 ± 51.1 kg, 69.2 ± 8.1 kg, 15483.1 ± 1104.8mm(2) and 51.7 ± 6.2%, for the LSP1RM in the 1RM, body mass, ∑CSA and muscle fiber type II percentage, respectively. The most important variable in the clusters division was the ∑CSA. In addition, the ∑CSA and muscle fiber type II percentage explained the variance in the 1RM performance (Adj R2=0.35, p=0.0001) for all participants and for the LSP1RM (Adj R2=0.25, p=0.002). For the HSP1RM, only the ∑CSA was entered in the model and showed the highest capacity to explain the variance in the 1RM performance (Adj R2=0.38, p=0.01). As a conclusion, the muscle CSA was the most relevant variable to predict force production in individuals with no strength training background.

Categorical structure and perception of facial expressions in dyadic same-different task

Emotional facial expressions are perceived categorically by individual subjects in discrimination and identification tasks (Young et al., 1997). We tested whether this effect can be replicated in shared same-different task. Participants, arranged in 15 dyads, were synchronously presented pairs of images for 3 s on two separate displays. The task was to discuss the images and decide, whether they were same or different, without seeing each other's image. As stimuli, we used 6 stills from video record of male poser performing transition between happy and surprised facial expressions. To explore the strategies used and structure of verbal categories, participants’ eye movements and speech were recorded. Overall task performance analysis showed categorical perception (better discrimination of images far from categories prototypes) in 1-step pairs, and U-shape function in pairs of identical images. Although free description was allowed, the verbal units used fall into three main categories: configural (describing facial features deformation), emotional and situational. Based on their performance, dyads of participants were divided into 3 equal groups. Comparison of verbal activity in contrast groups showed: in the low performance group (0.62–0.7), the mean amount of verbal units per trial was distributed equally across all stimuli pairs; in the high performance group (0.82–0.94), it increased significantly while discussing same images or 1-step pairs, and the use of emotion terms was more diverse (low group subjects preferred more general descriptors like "happy" and "surprised" without mentioning complex mixed emotions). Low performance dyads showed no clear categorical perception. Moreover, the average eye fixation patterns differed significantly: dyads with lower performance observed the eyes area longer, and subjects with higher performance paid more attention to the mouth region. We suggest that, on happy-sad transition, extended verbal description and relying on mouth transformation help to elaborate more effective strategies in dyadic images differentiation. Meeting abstract presented at VSS 2012

Effect of a Coteaching Handwriting Program for First Graders: One-Group Pretest–Posttest Design

We examined the effects of a cotaught handwriting and writing program on first-grade students grouped by low, average, and high baseline legibility. The program's aim was to increase legibility, handwriting speed, writing fluency, and written expression in students with diverse learning needs. Thirty-six first-grade students in two classrooms participated in a 12-wk handwriting and writing program cotaught by teachers and an occupational therapist. Students were assessed at pretest, posttest, and 6-mo follow-up using the Evaluation Tool of Children's Handwriting-Manuscript (ETCH-M) and the Woodcock-Johnson Writing Fluency and Writing Samples tests. Students made large gains in ETCH-M legibility (η² = .74), speed (η²s = .52-.65), Writing Fluency (η² = .58), and Writing Samples (η² = .59). Students with initially low legibility improved most in legibility; progress on the other tests was similar across low-, average-, and high-performing groups. This program appeared to benefit first-grade students with diverse learning needs and to increase handwriting legibility and speed and writing fluency.