Level Of Alertness Research Articles

Resourcefulness Intervention Efficacy for Parent Caregivers of Technology-Dependent Children: A Randomized Trial.

Parent caregivers of children who require lifesaving technology (e.g., mechanical ventilation, feeding tubes) must maintain a high level of vigilance 24/7. A two-arm randomized controlled trial tested the efficacy of a resourcefulness intervention on parents' mental/physical health and family functioning at four time points over six months. Participants (n = 93) cared for their technology-dependent children <18 years at home. The intervention arm received teaching on social (help-seeking), personal (self-help) resourcefulness skills; access to the intervention video and skill application video-vignettes; four weeks of skills reinforcement using daily logs; four weekly phone contacts; and booster sessions at two- and four-month postenrollment. The attention control arm received phone contact at identical time points plus the current standard of care. Statistically significant improvement was noted; fewer depressive cognitions and improved physical health for the intervention participants than attention control participants over time after controlling for covariates. The findings support the resourcefulness intervention efficacy.

Surgical results for hypertensive intracerebral hemorrhagesdepending on intervention timing

Study aim. To analyse the surgical outcomes in patients with haemorrhagic stroke depending on the timing of surgery.&#x0D; Materials and methods. We performed a retrospective analysis of 500 patients (335 (67%) men and 165 (33%) women), who underwent surgical treatment of hypertensive intracranial hemorrhages at the N.V. Sklifosovsky Research Institute for Emergency Medicine between 1997 and 2020. The mean patient age was 53.1 12.2 years. The mean time until surgery was 3.3 2.6 days. Outcomes were assessed on day 30 from disease onset using the modified Rankin Scale (mRS).&#x0D; Results. In the total sample, outcomes as measured by the mRS were as follows: type 0 84 (16.8%) patients, type 1 37 (7.4%), type 2 46 (9.2%), type 3 38 (7.6%), type 4 43 (8.6%), type 5 142 (28.4%) and type 6 110 (22.0%). Treatment results were better when surgery was delayed (2 = 64.4; p 0.00001). Mortality was 36.4% after surgery conducted in the first day after haemorrhage, while mRS scores of 02 made up 18.6%. Mortality was 20.4% after surgery conducted on the second or third day, and mRS scores of 02 made up 29.6%. Mortality was 17.4% after surgery conducted on day 47, and mRS scores of 02 outcomes were present in 49.0% of subjects. Mortality was 8.8% when surgery was performed on day 8 or later, and favourable outcomes were present in 48.5% of patients.&#x0D; Conclusion. Intracerebral haematoma excision on day 23 leads to better outcomes in patients with reduced levels of alertness up to sopor, while surgery after day 3 leads to better results in alert patients and those with obtundation.

Feel the beat: cape fur seal males encode their arousal state in their bark rate.

The cape fur seal is one of the most colonial mammal species in the world. Breeding colonies are composed of harems held by mature males (older than 10years) with up to 30 females and their pups, while roaming subadult males (younger and socially immature) are kept away from bulls' territories. As in other pinnipeds, cape fur seals are highly vocal and use acoustic signals in all their social interactions. Males produce barks-short vocalizations always produced in sequences-for territorial defense, mating behaviors, and agonistic interactions. These calls convey information about the sex, age class, and individual identity. This study investigated whether motivational cues such as the arousal state can be encoded in territorial males' barks and whether these cues are decoded by listening sub-adult males. The rate (number of calls per unit of time) and fundamental frequency of barks were found to significantly increase during high arousal state interactions (i.e., male-male confrontation) compared to spontaneous barks. Playback experiments revealed that subadult males responded with a higher level of vigilance when territorial males' barks had a faster bark rate. This mechanism of decoding the bulls' arousal state from barks will likely constitute an advantage for both bulls and the subadult males, by avoiding or reducing physical conflicts, and thereby reducing energy expenditure and the risk of injury. This study is the first experimental evidence of cape fur seals' using vocal rhythmic patterns to modulate their social interactions.

Clinical Characteristics and Outcomes of Children with Acute Catastrophic Brain Injury: A 13-Year Retrospective Cohort Study.

The purpose of this study was to describe and analyze clinical characteristics and outcomes in children with acute catastrophic brain injury (CBI). This was a single-center, 13-year (2008-2020) retrospective cohort study of children in the pediatric and cardiac intensive care units with CBI, defined as (1) acute neurologic injury based on clinical and/or imaging findings, (2) the need for life-sustaining intensive care unit therapies, and (3) death or survival with a Glasgow Coma Scale score < 13 at discharge. Patients were excluded if they were discharged directly to home < 14days from admission or had a chronic neurologic condition with a baseline Glasgow Coma Scale score < 13. The association between the primary outcome of death and clinical variables was analyzed by using Kaplan-Meier estimates and multivariable Cox proportional hazard models. Outcomes assessed after discharge were technology dependence, neurologic deficits, and Functional Status Score. Improved functional status was defined as a change in total Functional Status Score [Formula: see text] 2. Of 106 patients (58% boys, median age 3.9years) with CBI, 86 (81%) died. Withdrawal of life-sustaining therapies was the most common cause of death (60 of 86, 70%). In our multivariable analysis, each unit increase in admission pediatric sequential organ failure assessment score was associated with 10% greater hazard of death (hazard ratio 1.10, 95% confidence interval 1.04-1.17, p < .01). After controlling for admission pediatric sequential organ failure assessment scores, compared with those of patients with traumatic brain injury, all other etiologies of CBI were associated with a greater hazard of death (p = .02; hazard ratio 3.76-10). The median survival time for the cohort was 22days (95% confidence interval 14-37days). Of 23 survivors to hospital discharge, 20 were still alive after a median of 2years (interquartile range 1-3years), 6 of 20 (30%) did not have any technology dependence, 12 of 20 (60%) regained normal levels of alertness and responsiveness, and 15 of 20 (75%) had improved functional status. Most children with acute CBI died within 1month of hospitalization. Having traumatic brain injury as the etiology of CBI was associated with greater survival, whereas increased organ dysfunction score on admission was associated with a higher hazard of mortality. Of the survivors, some recovered consciousness and functional status and did not require permanent technology dependence. Larger prospective studies are needed to improve prediction of CBI among critically ill children, understand factors guiding clinician and family decisions on the continuation or withdrawal of life-sustaining treatments, and characterize the natural history and long-term outcomes among CBI survivors.

Temporal Dynamics of Subjective and Objective Alertness During Exposure to Bright Light in the Afternoon for 5 h.

Light can induce an alertness response in humans. The effects of exposure to bright light vs. dim light on the levels of alertness during the day, especially in the afternoon, as reported in the literature, are inconsistent. This study employed a multiple measurement strategy to explore the temporal variations in the effects of exposure to bright light vs. regular office light (1,200 lx vs. 200 lx at eye level, 6,500 K) on the alertness of participants for 5 h in the afternoon. In this study, 20 healthy adults (11 female; mean age 23.25 ± 2.3 years) underwent the Karolinska sleepiness scale (KSS), the auditory psychomotor vigilance test (PVT), and the waking electroencephalogram (EEG) test for two levels of light intervention. The results yielded a relatively lower relative delta power and a relatively higher beta power for the 1,200 lx condition in comparison with the 200 lx condition. However, the light conditions elicited no statistically significant differences in the KSS scores and performance with respect to the PVT. The results suggested that exposure to bright light for 5 h in the afternoon could enhance physiological arousal while exerting insignificant effects on subjective feelings and performance abilities relating to the alertness of the participants.

Movements and behaviors during spontaneous arousals in healthy young adults: an intermediary stage between wakefulness and sleep?

BackgroundArousals are common, sudden and transient elevations of the vigilance level during normal sleep, but arousal-associated behaviors have not yet been studied. ObjectiveWe aimed to describe the duration as well as motor and autonomic patterns associated with arousals across sleep stages in normal subjects. MethodsThe spontaneous arousals of 25 healthy young adults were randomly analyzed on polysomnography with body- and face-oriented video cameras. The duration of the heart rate response as well as the frequency, amplitude, speed, body segment and semiology of associated movements were measured. ResultsAmong 624 arousals (258 in N2, 140 in N3 and 226 in REM sleep), REM sleep arousals had the shortest duration, and N3 arousals were associated with greater heart rate acceleration. Movements and behaviors (mostly involving the head and neck, then the upper limbs, with rare eyes opening and no turning in bed) were frequent during arousals (69.4% during N2 sleep, 89.3% during N3 and 93.8% during REM sleep). Arousals more frequently included ample, prolonged and whole-body movements during N3 sleep and fast movements and facial expressions during REM sleep. During N2 arousals, chewing was the most prevalent behavior. Some movements resembled orientation and comfort behaviors (flexing/rotating the neck and trunk, scratching, pulling the sheets, rubbing the nose, yawning, smiling, frowning and speaking), whereas others resembled sleep-associated automatisms (swallowing, chewing). ConclusionIn contrast with previous assumptions, most arousals are associated with movements. The type of movements suggests that arousal is an intermediary state between wakefulness and sleep.

Sleep disruption and disorders in former college and professional American football players

AbstractBackgroundLittle is known about sleep in those with a history of contact sports, who are at increased risk for neurodegenerative disease(s). Sleep disruption and disorders are increasingly recognized as having a bidirectional relationship with Alzheimer’s disease neuropathology. Here, we investigated self‐reported sleep disruption and disorders in male former college and professional American football players.Method116 former National Football League (NFL) players, 60 former college football players, and 60 asymptomatic men without a history of traumatic brain injury or repetitive head impacts (controls), all between 45‐74 years, completed the Mayo Sleep Questionnaire (MSQ) which includes the Epworth Sleepiness Scale (ESS). Former American football players were enrolled across the spectrum of symptom severity (asymptomatic to mild dementia). Using binary logistic regression or analysis of covariance, comparisons (controlling for age, racial identity, body mass index, APOE e4 status) on each of the MSQ items and the ESS were made between each of the study groups.ResultCompared to controls, former NFL players were more likely to restless legs (OR = 7.32, 95% CI = 1.63‐32.97*), sleepwalking (OR = 8.65, 95% CI = 1.08‐69.22*), observed apnea (OR = 2.25, 95% CI = 1.04‐4.85*), lower alertness levels (marginal mean diff. = 0.90**) and had higher ESS (marginal mean diff. = 2.37**). Former college football players reported greater sleep disturbances compared with controls: restless legs (OR = 10.82, 95% CI = 1.86‐62.89**), sleepwalking (OR = 10.45, 95% CI = 1.12‐97.58*), alertness levels (marginal mean diff. = 1.48**) and ESS (marginal mean diff. = 2.76*). There were no college vs control differences for observed apnea. There were no differences between former NFL players and former college football players on any sleep metric. **p&lt;.005, *p&lt;.05.ConclusionSleep disturbances may be an important factor to investigate in those with a history of participation in American football.

Strategic vigilance and its role in promoting entrepreneurship of business organizations An exploratory study of the opinions of a sample of faculty staff at Al-Hadbaa University College

At the Iraqi environment level, the civil educational system aims to reach leadership by focusing on its main dimensions, namely (independence, anticipation, risk-taking, and creativity). To achieve this, it must reconsider its level of strategic vigilance in terms of providing its types (technological, marketing, competitiveness, environmental). Therefore, the main objective of the current research was to measure the actual role of strategic vigilance in promoting entrepreneurship of business organizations by determining the level of relationship and impact between them, As the Al-Hadba University College was chosen as a field for research, and by an intentional sample represented by the faculty members, which amounted to (60) people, and by adopting the questionnaire form as the primary tool in data collection, and to reach the results, a number of statistical tools were used, namely (correlation coefficient, linear regression), where Several conclusions were presented, the most important of which is the presence of a degree of actual contribution of the independent variable in the adopted variable, and this means the possibility of adopting types of strategic vigilance in enhancing the level of entrepreneurship of business organizations, and that the most significant proposals are the necessity of increasing the interest of the researched organization and its management by invoking the types of strategic vigilance in the field of work and directing it towards strengthening Entrepreneurship of business organizations, in a manner that contributes to the sustainability of their competitive advantage.

دور التعلم الممتع من خلال منهج الاقتصاد المنزلی فی تحسین الیقظة الذهنیة والانهماک بالتعلم لدى تلامیذ المرحلة الابتدائیة

ملخص البحث دور التعلم الممتع من خلال منهج الاقتصاد المنزلي في تحسين اليقظة الذهنية والانهماک بالتعلم لدى تلاميذ المرحلة الابتدائية هدف البحث الحالي إلى دراسة فعالية التعلم الممتع من خلال منهج الاقتصاد المنزلي في تحسين اليقظة الذهنية والانهماک بالتعلم لدى تلاميذ المرحلة الابتدائية ، وتکونت أدوات البحث من مقياس اليقظة الذهنية ومقياس الانهماک في التعلم، وتوصلت نتائج البحث إلى تحسن مستوى اليقظة الذهنية والانهماک بالتعلم لدى تلاميذ المجموعة التجريبية عن تلاميذ المجموعة الضابطة وذلک بعد إجراء تجربة البحث ، ومن توصيات البحث ضرورة استخدام التعلم الممتع کمنحى تعليمي في تعليم الاقتصاد المنزلي وخاصة لتلاميذ المرحلة الأساسية الدنيا. الکلمات المفتاحية : - التعلم الممتع Enjoyable learning - اليقظة الذهنية Mindfulness - الانهماک بالتعلم learning engagement Abstract The role of enjoyable learning through the home economics curriculum in improving Mindfulness and learning engagement among Primary stage students The aim of the current research is to study the effectiveness of enjoyable learning through the home economics approach in improving mindfulness and learning engagement among elementary school students, and the research tools consisted of the mindfulness scale and the measure of involvement in learning, and the results of the research reached an improvement in the level of mental alertness and learning engagement among the experimental group students On the authority of students of the control group, after conducting the research experiment. Among the recommendations of the research is the necessity to use enjoyable learning as an educational approach in teaching home economics, especially for pupils in the lower elementary stage.

CTNI-27. SINGLE AGENT ACTIVITY OF ONC201 IN NON-MIDLINE H3 K27M-MUTANT DIFFUSE GLIOMAS

Abstract BACKGROUND H3 K27M-mutant diffuse midline glioma is an invariably lethal form of brain cancer that disproportionately affects children and young adults and has no effective treatment following front-line radiation. The initial disease definition in the 2016 WHO Classification of Tumors of the Central Nervous System regarded the H3 K27M mutation as pathognomonic, though the definition was updated in 2018 restricting the diagnosis to histologically diffuse gliomas that involve midline CNS structures (cIMPACT-NOW update 2). ONC201 is an investigational anti- cancer small molecule, DRD2 antagonist and ClpP agonist that has induced durable tumor regressions by RANO-HGG criteria in a registration cohort of recurrent diffuse midline glioma, H3 K27M-mutant patients treated with single agent ONC201. METHODS We present 7 patients with H3 K27M-mutant diffuse gliomas were enrolled in ONC201 clinical studies, excluded from the registration cohort due to involvement of non-midline CNS structures, all within the cerebral hemispheres (3 frontal, 1 temporal, 1 frontotemporal, 1 parietal, and 1 corona radiata). RESULTS Two of the 7 patients underwent objective responses by RANO-HGG criteria as assessed by investigator, which was associated with clinical benefit that included increased mobility and level of alertness. CONCLUSIONS These results demonstrate that H3 K27M-mutant diffuse gliomas occur outside of midline CNS structures, and suggest that ONC201 has single agent activity in H3 K27M-mutant gliomas irrespective of CNS location.

Spatiotemporal Characteristics of Event-Related Potentials Triggered by Unexpected Events during Simulated Driving and Influence of Vigilance.

We investigated the spatiotemporal characteristics of brain activity due to sudden events during monotonous driving and how it changes with vigilance level. Two types of sudden events, emergency stop and car drifting, were presented using driving simulator, and event-related potentials (ERPs) were measured. From the ERPs of both types of events, an early component representing sensory information processing and a late component were observed. The early component was expected to represent sensory information processing, which corresponded to visual and somatosensory/vestibular information processing for the sudden stop and lane departure tasks, respectively. The late components showed spatiotemporal characteristics of the well-known P300 component for both types of events. Common characteristic brain activities occurred in response to sudden events, regardless of the type. The modulation of brain activity due to the vigilance level also shared common characteristics between the two types. We expect that our results will contribute to the development of an effective means to assist drivers’ reactions to ambulatory situations.

Vigilance Estimating in SSVEP-Based BCI Using Multimodal Signals.

Brain-computer interface (BCI) is a communication system that allows a direct connection between the human brain and external devices. With the application of BCI, it is important to estimate vigilance for BCI users. In order to investigate the vigilance changes of the subjects during BCI tasks and develop a multimodal method to estimate the vigilance level, a high-speed 4-target BCI system for cursor control was built based on steady-state visual evoked potential (SSVEP). 18 participants were recruited and underwent a 90-min continuous cursor-control BCI task, when electroencephalogram (EEG), electrooculogram (EOG), electrocardiography (ECG), and electrodermal activity (EDA) were recorded simultaneously. Then, we extracted features from the multimodal signals and applied regression models to estimate vigilance. Experimental results showed that the differential entropy (DE) feature could effectively reflect the change of vigilance. The vigilance estimation method, which integrates DE and EOG features into the support vector regression (SVR) model, achieved a better performance than the compared methods. These results demonstrate the feasibility of our methods for estimating vigilance levels in BCI.

Brain Arousal as Measured by EEG-Assessment Differs Between Children and Adolescents With Attention-Deficit/Hyperactivity Disorder (ADHD) and Depression.

Objective: Disturbed regulation of vigilance in the wake state seems to play a key role in the development of mental disorders. It is assumed that hyperactivity in adult ADHD is an attempt to increase a general low vigilance level via external stimulation in order to avoid drowsiness. For depression, the avoidance of stimulation is interpreted as a reaction to a tonic increased vigilance state. Although ADHD is assumed to start during childhood, this vigilance model has been barely tested with children diagnosed for ADHD so far.Methods: Resting-state EEG (8 min) measures from two groups of children diagnosed with either ADHD [N = 76 (16 female, 60 male), age: (mean/SD) 118/33 months] or depression [N = 94 (73 female, 21 male), age: 184/23 months] were analyzed. Using the VIGALL toolbox, EEG patterns of vigilance level, and regulation were derived and compared between both groups. In correlation analysis, the relations between vigilance measures, attentional test performance (alertness and inhibition), and mental health symptoms were analyzed.Results: Children with ADHD differed from children with most prominent depressive symptoms in brain arousal regulation and level, but EEG vigilance was not related to behavior problems and not related to the attentional test performance. Brain arousal was dependent on the age of the participant in the whole sample; younger children showed lower vigilance stages than teenagers; this effect was not present when analyzed separately for each diagnostic group. EEG assessment time and received medication had no effect on the EEG vigilance.Discussion: Although based on a small sample, this explorative research revealed that EEG vigilance level is different between children with ADHD and with depression. Moreover, even the standard procedure of the clinical routine EEG (resting state) can be used to differentiate brain arousal states between participants with ADHD and depression. Because routine EEG is not specialized to vigilance assessment, it may not be sufficiently sensitive to find vigilance–symptomatology associations. Further research should address developmental changes in EEG measurements in children and use bigger samples of participants within the same age range.

Evaluating the impacts of driver’s pre-warning cognitive state on takeover performance under conditional automation

To design better fallback procedures and enhance road safety for conditionally automated vehicles (SAE Level 3), it is important to understand the factors that affect driver’s takeover performance (i.e., driving performance while resuming manual control). This study investigates the impacts of driver’s pre-warning cognitive state (i.e., before the issuance of a takeover warning) on takeover performance. Most existing studies assess takeover performance by independently analyzing driving performance indicators (e.g., minimum time-to-collision and maximum deceleration), and thereby ignore their associated interdependencies. This study proposes a novel comprehensive takeover performance metric, Takeover Performance Index (TOPI), that combines multiple driving performance indicators representing three aspects of takeover performance: risk of collision, the intensity of the driver’s response, and trajectory quality. Further, the driver’s pre-warning cognitive state is estimated by analyzing neurophysiological data (i.e., brain electrical activity) measured using an electroencephalogram (EEG) for 118 participants in driving simulator experiments. Linear mixed models are estimated for takeover performance to analyze its linkages to the driver’s pre-warning cognitive state, novelty in takeover experience (i.e., prior experience with a takeover situation), type of takeover warning (i.e., non-mandatory takeover vs. mandatory takeover), age, and driving experience. In this study, most drivers intervened in non-mandatory takeover scenarios and exhibited poor takeover performance. We observed three crashes across 287 runs. The study results show that takeover performance decreases with age but increases with driving experience when the driver is under certain pre-warning cognitive states, including fatigue, drowsiness, passive attention, and low level of alertness. They also illustrate that the novelty in takeover experience and mandatory takeover warning negatively affects takeover performance. The study findings provide insights for developing operator training and licensing strategies, designing regulations for the use of automated vehicles, and factoring driver cognition in designing fallback procedures in automated vehicles.

Alertness and Visual Attention Impact Different Aspects of the Optokinetic Reflex.

PurposeAssessing visual attention and alertness is of great importance in visual and cognitive neuroscience, providing objective measures valuable for both researchers and clinicians. This study investigates how the optokinetic response differs between levels of visual attention in healthy adults while controlling for alertness.MethodsTwelve healthy subjects (8 men and 4 women; mean age = 33 ± 9.36) with intact gaze-stability, visual acuity, and binocularity were recruited. Subjects viewed a rotating visual scene provoking torsional optokinetic nystagmus (OKN) while wearing a video eye tracker in a seated head-fixed position. Tasks requiring focused, neutral, and divided visual attention were issued to each subject and the OKN was recorded. Pupil sizes were monitored as a proxy for alertness.ResultsPupil dilation was increased for both focused and divided visual attention. The number of nystagmus beats was highest for the focused condition and lowest for the divided attentional task. OKN gain was increased during both focused and divided attention. The distribution of nystagmus beats over time showed that only focused attention produced a reliable adaptation of the OKN.ConclusionsResults consequently indicate that OKN frequency is adaptive to a viewer's level of visual attention, whereas OKN gain is influenced by alertness levels. This pattern offers insight into the neural processes integrating visual input with reflexive motor responses. For example, it contextualizes why attention to visual stimuli can cause dizziness, as the OKN frequency reflects activity of the velocity storage mechanism. Additionally, the OKN could offer a possible venue for differentiating between visual attention and alertness during psychometric testing.

HER2-low breast cancer could be associated with an increased risk of brain metastasis.

The HER2-low breast cancer is a newly recognized entity with the clinical characteristics is yet to be defined. We hypothesized that HER2-low breast cancer could lead to an increased rate of brain metastases in patients with localized breast cancer. We tested this hypothesis in a large cohort of breast cancer patients with long follow-up. We included 2686 adult breast cancer patients followed up in Hacettepe University Cancer Center. Patients with 1 + positive HER2 expression and 2 + HER2 expression with a negative FISH were categorized as HER2-low disease. We evaluated the brain metastasis risk withbinary logistic regression analyses and reported odds ratios (OR) with 95% confidence intervals (CI). During a median 95.4 (IQR 72.6-123.1)month follow-up, 184 patients developed brain metastasis (6.9%). The brain metastases were developed in 5.1% of the patients with HER2-negativedisease, 8.5% of the patients with HER2-low disease, and 10.1% of the patients with HER2-positive disease. A multivariable binary logistic regression model demonstrated an increased risk of brain metastasis in patients with HER2-low disease (OR: 1.611, 95% CI 1.055-2.460, p = 0.027) and in HER2-positive patients (OR: 1.837, 95% CI 1.308-2.580, p < 0.001). Additionally, HR + -HER2-low disease was associated with a decreased DFS compared to HR + -HER2-negative disease (p = 0.008). In this study, we observed an increased risk of brain metastasis in localized breast cancer patients with HER2-low disease. We think that a high level of vigilance and a low threshold for brain imaging could benefit HER2-low breast cancer patients similar to the patients with HER-positive disease.

Comparison of Sleep and Attention Metrics Among Nurses Working Shifts on a Forward- vs Backward-Rotating Schedule

The association of fast backward-rotating shift work (ie, anticlockwise sequence of afternoon, morning, and night shifts) with subjective and objective measures of sleep-wake quality, daytime attention, and tiredness of health care workers has not yet been established. To investigate the association of shift rotation direction with tiredness, sleepiness, and sustained attention among nurses working forward- and backward-rotating shifts. Data of this cohort study were collected from nurses working at 5 midsized Italian hospitals. The nurses had either a forward-rotating schedule (ie, morning to afternoon to night) and or a backward-rotating schedule (ie, afternoon to morning to night). The data were collected from July 2017 to February 2020. Data analysis was performed from May to October 2020. Participants were working either forward- or backward-rotating schedules, in which the sequence of 3 shifts (morning, afternoon, and night) changed in a clockwise or anticlockwise direction. Sleep data were collected using the Karolinska Sleepiness Scale and Pittsburgh Sleep Quality Index. Sustained attention was measured using the Psychomotor Vigilance Task. Tiredness was evaluated using the Tiredness Symptom Scale. A total of 144 nurses (mean [SE] age, 41.3 [0.8] years; 92 women [63.9%]) participated in the study; 80 nurses had forward-rotating schedules, and 64 had backward-rotating schedules. Nurses with irregular sleep-wake patterns due to night shift work had poor sleep quality (46 [57.5%] in forward-rotating schedule group; 37 [57.8%] in backward-rotating schedule group). Nurses working backward-rotating shifts exhibited significantly greater sleepiness (F1,139 = 41.23; P < .001) and cognitive slowing (ie, longer median reaction times; F1,139 = 42.12; P < .001) than those working forward rotations. Importantly, these differences were not affected by age, years of employment, and quality of sleep. Of nurses working on a backward-rotating schedule, 60 (93.8%) reported elevated sleepiness (Karolinska Sleepiness Scale score ≥7) after the night shift. The median reaction time (F1,139 = 42.12; P < .001), 10% fastest reaction time (F1,139 = 97.07; P < .001), minor lapses (F1,139 = 46.29; P < .001), and reaction time distribution (F1,139 = 60.13; P < .001) of nurses on backward-rotating schedules indicated a lower level of vigilance, which is negatively associated with neurobehavioral performance. In this study, both shift rotation models were negatively associated with health and cognitive performance. These findings suggest that forward shift rotation may be more beneficial than backward rotation for several measured performance attentional outcomes and sleepiness. Optimization of shift rotations should be implemented to decrease the combination of the negative outcomes associated with shift work and reduce the potential risk of medical errors in health care systems.

Non-smooth dynamics emerging from predator-driven discontinuous prey dispersal

In ecology, the refuge protection of the prey plays a significant role in the dynamics of the interactions between prey and predator. In this paper, we investigate the dynamics of a non-smooth prey–predator mathematical model characterized by density-dependent intermittent refuge protection of the prey. The model assumes the population density of the predator as an index for the prey to decide on when to avail or discontinue refuge protection, representing the level of apprehension of the prey by the predators. We apply Filippov’s regularization approach to study the model and obtain the sliding segment of the system. We obtain the criterion for the existence of the regular or virtual equilibria, boundary equilibrium, tangent points, and pseudo-equilibria of the Filippov system. The conditions for the visibility (or invisibility) of the tangent points are derived. We investigate the regular or virtual equilibrium bifurcation, boundary-node bifurcation and pseudo-saddle-node bifurcation. Further, we examine the effects of dispersal delay on the Filippov system associated with prey vigilance in identifying the predator population density. We observe that the hysteresis in the Filippov system produces stable limit cycles around the predator population density threshold in some bounded region in the phase plane. Moreover, we find that the level of apprehension and vigilance of the prey play a significant role in their refuge-dispersion dynamics.

Analisis Persepsi Orang Dengan HIV (ODHIV) Terhadap Risiko Penularan COVID-19 Di Kota Padang Tahun 2021

People living with HIV (PLHIV) are group that have a weak immune system. In addition to HIV, the world is also facing the COVID-19 pandemic. The number of COVID-19 cases every time continues to increase until the current third wave. People living with HIV are a group that needs more attention in dealing with this pandemic. One way to initiate preventive action is to look at the perception of the protected aggregate. A person's level of alertness to an event can be seen from how they see the object to be perceived. Exploring the perception of people living with HIV can provide an overview of how they view and deal with COVID-19. This research use qualitative research methods with a phenomenological approach. The selection of participants used purposive sampling technique. The data analysis technique used the Colaizzi technique. There were ten themes found in this study, the views of people living with HIV on COVID-19, feelings of people living with HIV in dealing with COVID-19, awareness of differences in immune conditions and being a vulnerable group, belief in ARVs strengthening the body's immune system, views of people living with HIV on the risk of transmitting COVID-19, PLHIV's views on health protocols, activities that strengthen the immune system, social support, adaptation of Puskesmas services during a pandemic, PLHIV's perception of vaccination. The results of the study show that people living with HIV are a vulnerable population that needs more attention, especially during this COVID-19 pandemic. Cooperation between health care workers and policy makers should be increased to reach and protect the population of PLWHIV.

The spectrum of hearing abnormalities in patients living with diabetes mellitus.

Diabetes mellitus (DM) causes both micro- and macrovascular complications. The cochlea and auditory nerves are therefore at increased risk from DM-related complications due to microangiopathy, neuropathy or mitochondrial damage. Limited data are available from Africa detailing the association between DM and hearing impairment (HI). To describe the prevalence and spectrum of and associations with HI in patients living with DM (PLWD) with and without HIV infection. This was an analytical cross-sectional study conducted between 1 October and 31 December 2019 at the Edendale Hospital diabetes and audiology clinics in Pietermaritzburg, South Africa. PLWD had an audiological assessment using pure-tone audiometry together with a questionnaire enquiring about tinnitus, vertigo, dizziness and HI. A total of 296 PLWD (89.2% with type 2 DM) were enrolled, of whom 154 (52.0%) had HI. Type 2 PLWD had a significantly higher prevalence of reported symptoms and confirmed audiological HI, which was most often bilateral. The most frequent HI categories were mild to moderate, mild, and moderate to severe (33.8% v. 25.9% v. 23.9%, respectively). Significant associations were noted between dizziness (p=0.045), reported hearing loss (p&lt;0.001) and objective evidence of HI (all categories except mild). HI was significantly associated with age &gt;50 years, DM duration ≤10 years, female gender, hypertension, increased low-density lipoprotein and total cholesterol (TC), lower high-density lipoprotein cholesterol, suboptimal glycaemic control, non-proliferative retinopathy, sensory neuropathy and obesity (p&lt;0.05). Approximately half (48.9%) of PLWD and HIV infection had HI, and they were significantly younger and had higher TC levels than PLWD without HIV (p&lt;0.05). We showed that HI occurs in over half of PLWD, usually within the first 10 years after diagnosis of DM. Symptoms of HI were shown to have positive associations with all HI categories except mild. A high level of vigilance for HI must be maintained in PLWD.