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Acute mental fatigue, characterized by a transient decline in cognitive efficiency during or following prolonged cognitive tasks, can be managed through adaptive effort deployment. In response to mental fatigue, individuals can employ two main behavioral patterns: engaging a compensatory effort to limit performance decrements, or disengaging effort, leading to performance deterioration. This study investigated the behavioral pattern used by participants in mental fatigue conditions. Fifty participants underwent a sequential-task protocol with counterbalanced sessions who took place in two separate sessions: a 30-min incongruent Stroop task (fatiguing session) or a 30-min documentary viewing task (control session), followed by a time-to-exhaustion (TTE) handgrip task at 13 % of maximal voluntary contraction. Psychophysiological measures included the preejection period, heart rate variability, blood pressure, and respiration. Behavioral results showed deteriorated TTE handgrip performance after the Stroop task compared to after the documentary viewing task. During the Stroop task participants were more conservative and prioritized accuracy over speed. Self-reported fatigue was greater after the Stroop task. Psychophysiological data revealed a gradual decrease in sympathetic activity over time in both tasks, with the Stroop task showing a more pronounced decrease. Taken together, these findings suggest a disengagement of effort for a large proportion of participants (49 %) that could be partly attributed to a habituation to the demands of the Stroop task. This study illustrates the interplay of behavioral patterns of effort investment in the context of mental fatigue and underscores the role of disengagement as a dominant response to this phenomenon among healthy participants., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Mental fatigue can be studied by using either the time-on-task protocol or the sequential task protocol. In the time-on-task protocol, participants perform a long and effortful task and a decrease in performance in this task is generally observed over time. In the sequential task protocol, a first effortful or control task is followed by a second effortful task. The performance in the second task is generally worse after the effortful task than after the control task. The principal aim of the present experiment is to examine the relationship between these two decrements in performance while concomitantly using a sequential task protocol and assessing the performance of the first effortful task as a function of time-on-task. We expect a positive correlation between these two decrements in performance. A total of 83 participants performed a 30-min fatiguing mental task (i.e., a modified Stroop task) or a control task followed by a time-to-exhaustion handgrip task. As expected, this protocol combining the time-on-task and sequential task protocols allowed us to observe (1) a decrease in performance over time during the Stroop task, (2) a worst performance in the handgrip task after the Stroop task by comparison to the control task, (3) a positive correlation between these two effects. The decrease in performance during the Stroop task also correlated with the subjective measures of boredom and fatigue, whereas the detrimental effect observed in the handgrip task did not. Our findings suggest that the two fatigue-related phenomena share a common mechanism but are not completely equivalent., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Mangin, Audiffren, Lorcery, Mirabelli, Benraiss and André.)

During the 18 th century in Naples, Raimondo di Sangro, Prince of Sansevero, gave definitive form to the family chapel, the so-called "Cappella San Severo". The chapel houses not only extraordinarily beautiful and spectacularly detailed statues but also two human skeletons known as anatomical machines ("Macchine Anatomiche") in the basement. These two skeletons, a man and a pregnant woman, are entirely surrounded by their own circulatory system, just as they were suddenly and mysteriously, fixed. Legend, believed as truth until few years ago, tells that Prince Raimondo had prepared and injected an unknown embalming substance in their blood vessels convicting them to eternal fixity. Most recent investigations, however, demonstrated that while the bones are authentic, the blood vessels are actually an extraordinary artifact, even though the perfect reproduction of the coronary vascular tree, including congenital malformations in detail, raises some doubts about the technique used by the Prince. The dreadful aspect of these two skeletons appears to be in strident contrast with the classic beauty of the statues, which glorifies and celebrates the ideal of morphology. Conversely, the two "Anatomical Machines", protagonists of legends and superstitions since centuries, represent a marvelous example of science and art., Competing Interests: Conflict of Interest: None declared.

Unlabelled: We present a 74-year-old male with a chondrosarcoma, who presented with chest pain. The history, electrocardiogram (ECG), and biomarkers established the diagnosis of myocardial infarction (MI); angiography did not show coronary atherosclerosis and, both initial transthoracic echocardiogram and chest computed tomography (CT), did not demonstrate any cardiac abnormalities. A second echocardiogram following a routine ECG showed presence of a mass involving the right ventricle and the cardiac apex that was confirmed by chest CT scan. We underline the importance of considering cardiac tumors in the clinical arena of MI management., Learning Points: Cardiac tumors cause ECG changes similar to ischemic heart diseases.Keep in mind cardiac tumors when performing transthoracic echocardiogram (TTE) in the setting of suspected MI.TTE is the technique of choice in detecting cardiac tumors.

Background: The 64-slice multidetector-row computed tomography (MDCT) is an accurate noninvasive technique for assessing the degree of luminal narrowing in coronary arteries of patients with chronic ischemic disease. Aim of this study was to determine the value of MDCT in comparison to invasive coronary angiography (ICA) for detecting the presence and extent of coronary atherosclerotic plaques in a population of asymptomatic, hypertensive patients considered to be at high risk for cardiovascular events., Methods: We studied 67 asymptomatic, hypertensive patients at high-risk (Euro Score >5%). All patients had negative or nondiagnostic findings at exercise stress testing and therefore underwent both MDCT and ICA., Results: In the per-patient analysis, MDCT correctly identified 16/17 (94%) patients with significant coronary artery disease involving at least 1 vessel and 48/50 (96%) normal subjects. In the per-segment analysis, MDCT correctly detected 21/22 (95%) coronary segments with a stenosis >or=50% and 856/868 (98%) normal segments, with a high negative predictivity of normal scans (100%). There was a good concordance between MDCT and ICA, with a high Pearson correlation coefficient between the coronary narrowings with the two techniques (r=0.84, p<0.01). Mean coronary calcium score was higher for the 17 patients with significant coronary artery disease on ICA than in the 50 patients without (422+/-223 HU vs 72+/-21 HU p<0.001). The ROC curves identified 160 as the best calcium volumetric score cut-off value able to identify >or=1 significant coronary stenosis with sensitivity 88% and specificity 85%., Conclusions: MDCT is an excellent noninvasive technique for early identification of significant coronary stenoses in high risk asymptomatic hypertensive patients and might provide unique information for the screening of this broad population.

Background: The sequence of left ventricular (LV) systolic emptying is not completely understood. Using real-time 3-dimensional echocardiography, we investigated this sequence and LV synchronicity in physiological and pathological conditions., Methods and Results: The study population consisted of 116 healthy volunteers, 20 top-level athletes, 35 patients with LV dysfunction, and 84 patients with LV dysfunction and left bundle-branch block (LBBB). We subdivided the LV into 16 volumetric segments for regional analysis and into apical, middle, and basal regions to calculate the mean of end-systolic times and the time to minimum systolic volume of each region. In healthy volunteers and in top-level athletes, the emptying systolic times increased smoothly from apex to base. These differences determined an apex-to-base time gradient in the LV emptying sequence. In patients with LV dysfunction and without LBBB, this gradient was maintained with a relatively higher LV dyssynchrony. However, in patients with LV dysfunction and LBBB, there was no clear sequence in LV emptying volumes, and this group had the highest LV dyssynchrony., Conclusions: Real-time 3-dimensional echocardiography tomographic slicing of the LV enables accurate analysis of LV emptying in physiological conditions and in conditions of LV dysfunction with and without electrical dyssynchrony. Progressive dilation of LV produces deterioration in LV synchronicity. However, it is the presence of LV dysfunction in combination with LBBB that determines the loss of the apex-to-base time gradient in LV emptying.

Left atrial (LA) enlargement is a negative prognostic factor for survival in patients with stroke, congestive heart failure, and myocardial infarction. In the absence of mitral valvular disease it is also a marker of chronic elevated left ventricular filling pressures. The aim of our study was to examine whether the currently considered factors such as demographic, clinical, and Doppler parameters fully correspond to LA maximal volume measured by real time three-dimensional echocardiography (RT3DE). Two-hundred-twenty-four patients (age 58+/-12 years) were studied. Of these, 66 were healthy volunteers and 158 were patients with more than 2 cardiovascular risk factors (109), documented coronary heart disease (CHD) and normal LV function (33), and patients with (10) and without (6) IHD and LV systolic dysfunction. Two-dimensional Doppler and tissue Doppler (TDI) echocardiographic parameters and LA maximal volume, assessed by RT3DE were analyzed. LA maximal volume values were positively and highly significantly associated, after adjustment for age and sex, with LV mass, mitral flow peak E velocity and E/A ratio, TDI E'/A' ratio and E/e' ratio (P<0.001). There were highly significant inverse associations of LA maximal volume and ejection fraction and peak A' velocity detected by TDI (P<0.0001). LA maximal volume was significantly correlated with the progression of diastolic dysfunction from normal to grade III. In particular, there was a clear difference between the normal and pseudonormal filling patterns (p<0.001) in terms of LA maximal volume. In conclusion, progressive LA volume increase is directly correlated with age, LV mass, and LV diastolic dysfunction, and inversely correlated with LV systolic function.