Change in heart rate variability with increasing time-on-task as a marker for mental fatigue: A systematic review.

Fatigue-specific changes in the autonomic nervous system are often assumed to underlie the development of mental fatigue caused by prolonged cognitive tasks (i.e. Time-on-Task). Therefore, several previous studies have chosen to investigate the Time-on-Task related changes in heart rate variability (HRV). However, previous studies have used many different HRV indices, and their results often show inconsistencies. The present study, therefore, systematically reviewed previous empirical HRV studies with healthy individuals and in which mental fatigue is induced by prolonged cognitive tasks. Articles relevant to the objectives were systematically searched and selected by applying the PRISMA guidelines. We screened 360 records found on 4 databases and found that 19 studies were eligible for full review in accordance with the inclusion criteria. In general, all studies reviewed (with the exception of two studies) found significant changes in HRV with increasing Time-on-Task, suggesting that HRV is a reliable autonomic marker for Time-on-Task induced fatigue. The most conclusive HRV indices that showed a consistent Time-on-Task effect were the low frequency component of HRV and the time domain indices, particularly the root mean square of successive differences. Time-on-Task typically induced an increasing trend in both type of measures.

Correction: Enhanced cardiac vagal tone in mental fatigue: Analysis of heart rate variability in Time-on-Task, recovery, and reactivity.

[This corrects the article DOI: 10.1371/journal.pone.0238670.].

Gen Z and HIV-Strategies for Optimizing the Care of the Next Generation of Adolescents Living with HIV.

The management of adolescents living with HIV represents a particular challenge in the global response to HIV. The challenges specific to this age group include difficulties engaging and maintaining them in care, challenges with transition to adult care, and limited therapeutic options for treatment-experienced patients, all of which have been jeopardized by the COVID-19 pandemic. This paper summarizes some of the challenges in managing adolescents living with HIV, as well as some of the most recent and innovative therapeutic approaches in this population.

Revisiting the link between the sustained attention to response task (SART) and daily-life cognitive failures.

In this study, we examined the relationship betweenerrors of commissionon theSustained Attention to Response Task(SART)andscores on the Cognitive Failures Questionnaire (CFQ). The goal was to assess theecological validity of the SARTin a sample of people scoring high on fatigue complaints.SART errors of commission were positively associated with CFQ scores and this finding remained after controlling for fatigue level, age, and SART reaction times.Thus, our results generally supported the ecological validity of the SART. However, when examining subsamples separately, we found the association between SART and CFQ only in our subsample of employees, not in our subsample of university students. The three subscales of the CFQ showed the same pattern of findings. Our results imply that, when using the SART to draw conclusions about everyday life, it is crucial to consider the characteristics of one's sample and control for relevant confounding variables.

Probiotics for children with uncomplicated severe acute malnutrition (PruSAM study): A randomized controlled trial in the Democratic Republic of Congo.

BACKGROUND: Severe acute malnutrition (SAM) contributes to nearly 1 million deaths annually worldwide, with diarrhea and pneumonia being the common morbidity associated with mortality. OBJECTIVES: To assess the effect of probiotics on diarrhea, pneumonia, and nutritional recovery in children with uncomplicated SAM. METHODS: A randomized, double-blind, placebo-controlled study was conducted involving 400 children with uncomplicated SAM randomly assigned to ready-to-use therapeutic food (RUTF) either with (n = 200) or without (n = 200) probiotics. Patients received 1 mL daily dose of a blend of Lacticasebacillus rhamnosus GG and Limosilactobacillus reuteri DSM 17938 (dosage, 2 billion colony-forming units; 50:50) or placebo during 1 mo. They were simultaneously fed with the RUTF for 6 to 12 wk, depending on patients' recovery rates. The primary outcome was the duration of diarrhea. Secondary outcomes included diarrheal and pneumonic incidence, nutritional recovery, and transfer to inpatient care rate. RESULTS: For children with diarrhea, the number of days of disease was lower in the probiotic group (4.11; 95% CI: 3.37, 4.51) than that in the placebo group (6.68; 95% CI: 6.26, 7.13; P < 0.001). For children aged 16 mo or older, the risk of diarrhea was lower in the probiotic group (75.6%; 95% CI: 66.2, 82.9) than that in the placebo group (95.0%; 95% CI: 88.2, 97.9; P < 0.001), but no significant difference of the risk for the youngest. In the probiotic group, nutritional recovery happened earlier: at the 6th wk, 40.6% of the infants were waiting for nutritional recovery, contrasting with 68.7% of infants in the placebo group; but the nutritional recovery rate at the 12th wk was similar between the groups. Probiotics had no effect on pneumonic incidence and transfer to inpatient care. CONCLUSIONS: This trial supports using probiotics for the treatment of children with uncomplicated SAM. Its effect on diarrhea could positively affect nutritional programs in resource-limited settings. This trial was registered https://pactr.samrc.ac.za as PACTR202108842939734.

The General Factor of Personality (GFP) is associated with higher salary, having a leadership position, and working in a social job.

Previous studies have suggested that a general factor exists at the top of the hierarchal structure of personality. One interpretation of this General Factor of Personality (GFP) is that it reflects social effectiveness. Accordingly, in a large employee sample (N = 1267), we tested whether the GFP relates to several outcomes assumed to be linked with social effectiveness. Specifically, we examine whether the GFP is positively related to salary and to obtaining a leadership position. Additionally, we test whether high-GFP employees more often work in social occupations. Controlling for demographics and background variables, it was found that the GFP is indeed positively related to monthly (gross) salary. Moreover, employees occupying leadership positions in organizations scored higher on the GFP. GFP scores of employees in more social occupations (e.g., education, health care) were higher than of employees in other types of jobs (e.g., construction). GFP scores were also positively associated with the extent to which one has to relate to others in the job. Overall, the pattern of findings is in line with the notion of the GFP as relating to social effectiveness or adaptiveness, which are assumed to play a significant role in occupational outcomes.

Changes in pupil dilation and P300 amplitude indicate the possible involvement of the locus coeruleus-norepinephrine (LC-NE) system in psychological flow.

Psychological flow is a state of full task immersion. The present study was conducted to test the hypothesis that psychological flow is positively related to activity of the phasic locus coeruleus-norepinephrine (LC-NE) system, which supports decisions on whether to engage in or disengage from the current activity. Subjective flow was assessed among 36 participants who engaged in a gamified version of the n-back task with various difficulty levels (0, 1, 2, and 3 back). During the tasks, continuous pupil diameter and EEG were recorded. We found that psychological flow and two presumed indicators of the phasic LC-NE activity (pupil dilation and EEG P300 amplitude) fit inverted U-shapes with increasing subjective task difficulty. Moreover, a positive linear relationship between psychological flow and pupil dilation (not with P300) was found. In conclusion, this study indicates the involvement of the LC-NE system in the peak experience of flow.

Generalisable machine learning models trained on heart rate variability data to predict mental fatigue.

A prolonged period of cognitive performance often leads to mental fatigue, a psychobiological state that increases the risk of injury and accidents. Previous studies have trained machine learning algorithms on Heart Rate Variability (HRV) data to detect fatigue in order to prevent its consequences. However, the results of these studies cannot be generalised because of various methodological issues including the use of only one type of cognitive task to induce fatigue which makes any predictions task-specific. In this study, we combined the datasets of three experiments each of which applied different cognitive tasks for fatigue induction and trained algorithms that detect fatigue and predict its severity. We also tested different time window lengths and compared algorithms trained on resting and task related data. We found that classification performance was best when the support vector classifier was trained on task related HRV calculated for a 5-min time window (AUC = 0.843, accuracy = 0.761). For the prediction of fatigue severity, CatBoost regression showed the best performance when trained on 3-min HRV data and self-reported measures (R2 = 0.248, RMSE = 17.058). These results indicate that both the detection and prediction of fatigue based on HRV are effective when machine learning models are trained on heterogeneous, multi-task datasets.

SARS-CoV-2 Transmission in Belgian French-Speaking Primary Schools: An Epidemiological Pilot Study.

Schools have been a point of attention during the pandemic, and their closure one of the mitigating measures taken. A better understanding of the dynamics of the transmission of SARS-CoV-2 in elementary education is essential to advise decisionmakers. We conducted an uncontrolled non-interventional prospective study in Belgian French-speaking schools to describe the role of attending asymptomatic children and school staff in the spread of COVID-19 and to estimate the transmission to others. Each participant from selected schools was tested for SARS-CoV-2 using a polymerase chain reaction (PCR) analysis on saliva sample, on a weekly basis, during six consecutive visits. In accordance with recommendations in force at the time, symptomatic individuals were excluded from school, but per the study protocol, being that participants were blinded to PCR results, asymptomatic participants were maintained at school. Among 11 selected schools, 932 pupils and 242 school staff were included between January and May 2021. Overall, 6449 saliva samples were collected, of which 44 came back positive. Most positive samples came from isolated cases. We observed that asymptomatic positive children remaining at school did not lead to increasing numbers of cases or clusters. However, we conducted our study during a period of low prevalence in Belgium. It would be interesting to conduct the same analysis during a high prevalence period.

Bacteriophage-antibiotic combination therapy against extensively drug-resistant Pseudomonas aeruginosa infection to allow liver transplantation in a toddler.

Post-operative bacterial infections are a leading cause of mortality and morbidity after ongoing liver transplantation. Bacteria causing these infections in the hospital setting can exhibit high degrees of resistance to multiple types of antibiotics, which leads to major therapeutic hurdles. Alternate ways of treating these antibiotic-resistant infections are thus urgently needed. Phage therapy is one of them and consists in using selected bacteriophage viruses - viruses who specifically prey on bacteria, naturally found in various environmental samples - as bactericidal agents in replacement or in combination with antibiotics. The use of phage therapy raises various research questions to further characterize what determines therapeutic success or failure. In this work, we report the story of a toddler who suffered from extensively drug-resistant Pseudomonas aeruginosa sepsis after liver transplantation. He was treated by a bacteriophage-antibiotic intravenous combination therapy for 86 days. This salvage therapy was well tolerated, without antibody-mediated phage neutralization. It was associated with objective clinical and microbiological improvement, eventually allowing for liver retransplantation and complete resolution of all infections. Clear in vitro phage-antibiotic synergies were observed. The occurrence of bacterial phage resistance did not result in therapeutic failure, possibly due to phage-induced virulence tradeoffs, which we investigated in different experimental models.

Outbreak of invasive meningococcal disease caused by a meningococcus serogroup B in a nursery school, Wallonia, Belgium, 2018.

Although most invasive meningococcal disease (IMD) cases are sporadic without identified transmission links, outbreaks can occur. We report three cases caused by meningococcus B (MenB) at a Belgian nursery school over 9 months. The first two cases of IMD occurred in spring and summer 2018 in healthy children (aged 3-5 years) attending the same classroom. Chemoprophylaxis was given to close contacts of both cases following regional guidelines. The third case, a healthy child of similar age in the same class as a sibling of one case, developed disease in late 2018. Microbiological analyses revealed MenB with identical finetype clonal complex 269 for Case 1 and 3 (unavailable for Case 2). Antimicrobial susceptibility testing revealed no antibiotic resistance. Following Case 3, after multidisciplinary discussion, chemoprophylaxis and 4CMenB (Bexsero) vaccination were offered to close contacts. In the 12-month follow-up of Case 3, no additional cases were reported by the school. IMD outbreaks are difficult to manage and generate public anxiety, particularly in the case of an ongoing cluster, despite contact tracing and management. This outbreak resulted in the addition of MenB vaccination to close contacts in Wallonian regional guidelines, highlighting the potential need and added value of vaccination in outbreak management.

Visually guided movement with increasing time-on-task: Differential effects on movement preparation and movement execution.

Top-down cognitive control seems to be sensitive to the detrimental effects of fatigue induced by time-on-task (ToT). The planning and preparation of the motor responses may be especially vulnerable to ToT. Yet, effects of ToT specific to the different phases of movements have received little attention. Therefore, in three experiments, we assessed the effect of ToT on a mouse-pointing task. In Experiment 1, there were 16 possible target positions with variable movement directions. In Experiment 2, the layout of the targets was simplified. In Experiment 3, using cuing conditions, we examined whether the effects of ToT on movement preparation and execution were caused by an increased orientation deficit or decreased phasic alertness. In each experiment, initiation of movement (preparatory phase) became slower, movement execution became faster and overall response time remained constant with increasing ToT. There was, however, no significant within-person association between the preparatory and execution phases. In Experiments 1 and 2, we found a decreasing movement time/movement error ratio, suggesting a more impulsive execution of the pointing movement. In addition, ToT was also accompanied with imprecise movement execution as indicated by the increased errors, mainly in Experiment 2. The results of Experiment 3 indicated that ToT did not induce orientation and phasic alerting deficits but rather was accompanied by decreased tonic alertness.

The General Factor of Personality as Ego-Resiliency.

It was originally hypothesized by Block that what has come to be known as the General Factor of Personality (GFP) reflects ego-resiliency. We test Block's hypothesis in two studies. In Study 1 a meta-analysis (N = 15,609) examining the relationship between the GFP and ego-resiliency/resilience was conducted. In Study 2 (N = 157) archival data from Block and Block was used to examine the association between rater judged ego-resiliency across childhood, adolescence, and into early adulthood and the GFP based on self-report in early adulthood. Using structural equation modeling for the meta-analytic data, the correlation between the GFP and ego-resiliency/resilience was estimated at r = 0.93. Using a trait-state occasion model to test the hypothesis in Study 2, the correlation between the GFP and rated ego-resiliency was estimated at r = 0.85. The results of the two studies offer substantial support for Block's original hypothesis. Given the strength of the associations between the GFP and ego-resiliency/resilience one may conclude that the two constructs largely reflect the same underlying phenomenon.

A Case of In Situ Phage Therapy against Staphylococcus aureus in a Bone Allograft Polymicrobial Biofilm Infection: Outcomes and Phage-Antibiotic Interactions.

Phage therapy (PT) shows promising potential in managing biofilm infections, which include refractory orthopedic infections. We report the case of a 13-year-old girl who developed chronic polymicrobial biofilm infection of a pelvic bone allograft after Ewing's sarcoma resection surgery. Chronic infection by Clostridium hathewayi, Proteus mirabilis and Finegoldia magna was worsened by methicillin-susceptible Staphylococcus aureus exhibiting an inducible Macrolides-Lincosamides-Streptogramin B resistance phenotype (iMLSB). After failure of conventional conservative treatment, combination of in situ anti-S. aureus PT with surgical debridement and intravenous antibiotic therapy led to marked clinical and microbiological improvement, yet failed to prevent a recurrence of infection on the midterm. This eventually led to surgical graft replacement. Multiple factors can explain this midterm failure, among which incomplete coverage of the polymicrobial infection by PT. Indeed, no phage therapy against C. hathewayi, P. mirabilis or F. magna could be administered. Phage-antibiotic interactions were investigated using OmniLog® technology. Our results suggest that phage-antibiotic interactions should not be considered "unconditionally synergistic", and should be assessed on a case-by-case basis. Specific pharmacodynamics of phages and antibiotics might explain these differences. More than two years after final graft replacement, the patient remains cured of her sarcoma and no further infections occurred.

A role of serotonin and the insula in vigor: Tracking environmental and physiological resources.

We describe a neural monitor of environmental and physiological resources that informs effort expenditure. Depending on resources and environmental stability, serotonergic and dopaminergic neuromodulations favor different behavioral controls that are organized in corticostriatal loops. This broader perspective produces some suggestions and questions that may not be covered by the foraging approach to vigor of Shadmehr and Ahmed (2020).

The Neuroscience of the Flow State: Involvement of the Locus Coeruleus Norepinephrine System.

Flow is a state of full task engagement that is accompanied with low-levels of self-referential thinking. Flow is considered highly relevant for human performance and well-being and has, therefore, been studied extensively. Yet, the neurocognitive processes of flow remain largely unclear. In the present mini-review we focus on how the brain's locus coeruleus-norepinephrine (LC-NE) system may be involved in a range of behavioral and subjective manifestations of flow. The LC-NE system regulates decisions regarding task engagement vs. disengagement. This is done via different modes of baseline and stimulus-evoked norepinephrine release. We emphasize the theoretical and empirical overlap between the LC-NE system and flow. For both, a match between a person's skill and task challenge is important in order to induce high levels task-related attention. Moreover, psychophysiological indicators of LC-NE system activity, such as eye pupil diameter and arousal are also sensitive to flow states. Flow is related to arousal in an inverted U-shape. Similarly, in theories on the LC-NE system, task engagement is highest with intermediate levels of arousal. We argue that knowledge about the role of the LC-NE system in establishing the flow experience may help to gain fundamental knowledge of flow and can contribute to unifying various empirical findings on this topic.

Minimum acceptable diet among children aged 6-23 months in South Kivu, Democratic Republic of Congo: a community-based cross-sectional study.

BACKGROUND: Suboptimal child nutrition remains the main factor underlying child undernutrition in Democratic Republic of Congo (DRC). This study aimed to assess the prevalence of minimum acceptable diet and associated factors among children aged 6-23 months old. METHODS: Community-based cross-sectional study including 742 mothers with children aged 6-23 months old was conducted in 2 Health Zones of South Kivu, Eastern DRC. WHO indicators of Infant and Young Child Feeding (IYCF) regarding complementary feeding practices were used. Logistic regression analysis was used to quantify the association between sociodemographic indicators and adequate minimum acceptable diet for both univariate and multivariate analysis. RESULTS: Overall, 33% of infants had minimum acceptable diet. After controlling for a wide range of covariates, residence urban area (AOR 2.39; 95% CI 1.43, 3.85), attendance postnatal care (AOR 1.68; 95% CI 1.12, 2.97), education status of mother (AOR 1.83; 95% CI 1.20, 2.77) and household socioeconomic status (AOR 1.72; 95% CI 1.14, 2.59) were factors positively associated with minimum acceptable diet. CONCLUSION: Actions targeting these factors are expected to improve infant feeding practices in South Kivu.

SARS-CoV-2 and pediatric solid organ transplantation: Current knowns and unknowns.

The COVID-19 pandemic has proven to be a challenge in regard to the clinical presentation, prevention, diagnosis, and management of SARS-CoV-2 infection among children who are candidates for and recipients of SOT. By providing scenarios and frequently asked questions encountered in routine clinical practice, this document provides expert opinion and summarizes the available data regarding the prevention, diagnosis, and management of SARS-CoV-2 infection among pediatric SOT candidates and recipients and highlights ongoing knowledge gaps requiring further study. Currently available data are still lacking in the pediatric SOT population, but data have emerged in both the adult SOT and general pediatric population regarding the approach to COVID-19. The document provides expert opinion regarding prevention, diagnosis, and management of SARS-CoV-2 infection among pediatric SOT candidates and recipients.