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In everyday life, we are continuously struggling at focusing on our current goals while at the same time avoiding distractions. Attention is the neuro-cognitive process devoted to the selection of behaviorally relevant sensory information while at the same time preventing distraction by irrelevant information. Distraction can be prevented proactively, by strategically prioritizing task-relevant information at the expense of irrelevant information, or reactively, by suppressing the ongoing processing of distractors. The distinctive neuronal signature of these suppressive mechanisms is still largely unknown. Thanks to machine-learning decoding methods applied to prefrontal cortical activity, we monitor the dynamic spatial attention with an unprecedented spatial and temporal resolution. We first identify independent behavioral and neuronal signatures for long-term (learning-based spatial prioritization) and short-term (dynamic spatial attention) mechanisms. We then identify distinct behavioral and neuronal signatures for proactive and reactive suppression mechanisms. We find that while distracting task-relevant information is suppressed proactively, task-irrelevant information is suppressed reactively. Critically, we show that distractor suppression, whether proactive or reactive, strongly depends on the implementation of both long-term and short-term mechanisms of selection. Overall, we provide a unified neuro-cognitive framework describing how the prefrontal cortex deals with distractors in order to flexibly optimize behavior in dynamic environments., (© The Author(s) 2021. Published by Oxford University Press.)

Recent studies suggest that attention samples space rhythmically through oscillatory interactions in the frontoparietal network. How these attentional fluctuations coincide with spatial exploration/displacement and exploitation/selection by a dynamic attentional spotlight under top-down control is unclear. Here, we show a direct contribution of prefrontal attention selection mechanisms to a continuous space exploration. Specifically, we provide a direct high spatio-temporal resolution prefrontal population decoding of the covert attentional spotlight. We show that it continuously explores space at a 7-12 Hz rhythm. Sensory encoding and behavioral reports are increased at a specific optimal phase w/ to this rhythm. We propose that this prefrontal neuronal rhythm reflects an alpha-clocked sampling of the visual environment in the absence of eye movements. These attentional explorations are highly flexible, how they spatially unfold depending both on within-trial and across-task contingencies. These results are discussed in the context of exploration-exploitation strategies and prefrontal top-down attentional control.

The role of norepinephrine (NE) in visuo-spatial attention remains poorly understood. Our goal was to identify the attentional processes influenced by atomoxetine (ATX) injections, a NE-reuptake inhibitor that boosts the level of NE in the brain, and to characterize these influences. We tested the effects of ATX injections, on seven monkeys performing a saccadic cued task in which cues and distractors were used to manipulate spatial attention. We found that when the cue accurately predicted the location of the upcoming cue in 80% of the trials, ATX consistently improved attentional orienting, as measured from reaction times (RTs). These effects were best accounted for by a faster accumulation rate in the valid trials, rather than by a change in the decision threshold. By contrast, the effect of ATX on alerting and distractor interference was more inconsistent. Finally, we also found that, under ATX, RTs to non-cued targets were longer when these were presented separately from cued targets. This suggests that the impact of NE on visuo-spatial attention depends on the context, such that the adaptive changes elicited by the highly informative value of the cues in the most frequent trials were accompanied by a cost in the less frequent trials., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The Tunisian health care system is experiencing a significant period of change and needs reforms so as to adapt. The nursing profession, which is the main actor of this system, in terms of number and function, is barely known or utterly unknown. The present paper's authors, who are paramedical teachers, aim to shed light on the specificity of the nursing and the nursing profession based on data collecting, and rare articles and legislation texts. In four sections, the paper will discuss the following issues: the nursing population demography, providing several indicators, their training throughout the reforms period, their training which has been "hooked" to university studies, their job profile and career plan. This presentation will also address the situation in Algeria and Morocco, based on data available on the Web. The acquisition of "core" skills and skills "shared with other caregivers" represents the roadmap for the drafters of the training benchmarks currently under drafting. The higher institutes of nursing are looking of ways to secure the required trainers and resources needed to the opening of departments, prior to the launch of a 'doctoral school', which represents the only incubator of future teachers and researchers. Private training institutions representing a new investment sector are to be assessed in terms of overall employability. Perspectives, in 12 points, should be planned for a pedagogically accredited, professionally performing and socially responsible profession.

Cytotoxic chemotherapy suppresses the haematopoietic system, febrile neutropenia is the most serious haematological toxicity associated with the risk of life-threatening infections. We present a retrospective study of 200 episodes of febrile neutropenia in 128 patients treated in department of medical oncology. The aim of this study was to determinate the clinical, therapeutic and evolutive characteristics in patients treated essentially for solid tumors. Among these patients, 72% of them have at least two episodes, the median age was 34 years with extremes six and 75 years. It has been noticed that 26.3% of patients have diabetes, the dominate neoplasm was solid tumors in 79.7%, 65% of patients have received preventive colony-stimulating factors, 83% have received preventive buccal disinfection with antifungic. The median duration of hospitalisation was 12 days, the median delay of febrile neutropenia was 10 days with extremes two and 31 days, median duration of febrile neutropenia was 5.45 days with extremes one and 24 days. Among these cases, 9.45% of them have nadir zero, 68% of patients have clinical documented infections, ORL in 47% of cases. According to the study, 12% of cases have documented microbiological fever, the sites was urinary in 33% of cases, blood in 33% of cases, derm in 30% of cases. The microbe was staphylococcus negative coagulase in 37.5% essentially in blood and derm, the Escherichia coli in 20.8% essentially in urinary and blood. First line antibiotherapy was cefotaxim associated with amikacine in 93.5%, second line antibiotherapy was association of imipenam and amikacine in 82% of cases. Among these cases,7% of them have received anti-staphylococcus, and antifungic treatment in 50% of cases. The thermic defervescence was obtained in median delay of 2.8 days. We have noted nine deaths (22% of cases). Recent surveys indicate that neutropenia remains a prevalent problem associated with substantial morbidity, mortality and costs. The colony-stimulating have used effectively in a variety of clinical settings to prevent or treat febrile neutropenia and to assist patients receiving dose-intensive chemotherapy.