The occipital alpha rhythm (∼10 Hz) is the most prominent electrophysiological activity in the awake human brain 1, yet its functional role 2–4 and relation to visual perception 5 are little ...understood. Transient stimuli normally elicit a short series of positive and negative deflections lasting between 300 and 500 ms 6–8: the visual-evoked potential (VEP). Alpha oscillations, on the other hand, are generally suppressed by transient visual input 1, 8; they only augment in response to periodic (“steady-state”) inputs around 10 Hz 9, 10. Here, we applied reverse-correlation techniques to the visual presentation of random, nonperiodic dynamic stimulation sequences and found that the brain response to each stimulus transient was not merely a short-lived VEP but also included a strong ∼10 Hz oscillation that lasted for more than 1 s. In other words, the alpha rhythm implements an “echo” or reverberation of the input sequence. These echoes are correlated in magnitude and frequency with the observer's occipital alpha rhythm, are enhanced by visual attention, and can be rendered perceptually apparent in the form of ∼10 Hz flicker. These findings suggest a role for the alpha rhythm in the maintenance of sensory representations over time.
► EEG responses to random visual inputs contain a 10 Hz echo of the stimulation ► These echoes last up to 1 s (much longer than classic visual-evoked potentials) ► The echoes are tied to the occipital alpha rhythm but enhanced by attention ► The alpha rhythm may serve a role in maintaining sensory representations over time
In this article, we establish a new phenomenon of “inattentional deafness” and highlight the level of load on visual attention as a critical determinant of this phenomenon. In three experiments, we ...modified an inattentional blindness paradigm to assess inattentional deafness. Participants made either a low- or high-load visual discrimination concerning a cross shape (respectively, a discrimination of line color or of line length with a subtle length difference). A brief pure tone was presented simultaneously with the visual task display on a final trial. Failures to notice the presence of this tone (i.e., inattentional deafness) reached a rate of 79% in the high-visual-load condition, significantly more than in the low-load condition. These findings establish the phenomenon of inattentional deafness under visual load, thereby extending the load theory of attention (e.g., Lavie,
Journal of Experimental Psychology. Human Perception and Performance, 25, 596–616,
1995
) to address the cross-modal effects of visual perceptual load.
After a brief synopsis of the main avenues of research on the industrial organization of food and agriculture, I introduce and discuss the six articles that make up this Special Issue of the
Review
. ...The articles draw on novel databases to explore price transmission and supply response in processing tomatoes; concentration and competition in the meatpacking industries; communication and collusion in broiler production; concentration and research competition in genetically engineered seeds; price transmission from agricultural commodities through to retail prices; and the effect of store entry on prices for nearby retailers.
The chemical modification of proteins is an enabling technology for many scientific fields, including chemical biology, biophysics, bioengineering and materials science. These methods allow the ...attachment of strategically selected detection probes, polymers, drug molecules and analysis platforms. However, organic reactions that can proceed under conditions mild enough to maintain biomolecular function are limited. Even more rare are chemical strategies that can target a single site, leading to products with uniform properties and optimal function. We present a versatile method for the selective modification of protein N termini that does not require any genetic engineering of the protein target. This reaction is demonstrated for 12 different proteins, including the soluble domain of the human estrogen receptor. The function of this protein was confirmed through the binding of a fluorescent estrogen mimic, and the modified protein was explored as a prototype for the detection of endocrine-disrupting chemicals in water.
There has been a rapid emergence of numerous targeted agents in the oncology community in the last decade. This exciting paradigm shift in drug development lends promise for the future of ...individualized medicine. Given the pace of development and clinical deployment of targeted agents with novel mechanisms of action, dermatology providers may not be familiar with the full spectrum of associated skin-related toxicities. Cutaneous adverse effects are among the most frequently observed toxicities with many targeted agents, and their intensity can be dose-limiting or lead to therapy discontinuation. In light of the often life-saving nature of emerging oncotherapeutics, it is critical that dermatologists both understand the mechanisms and recognize clinical signs and symptoms of such toxicities in order to provide effective clinical management. Part I of this continuing medical education article will review in detail the potential skin-related adverse sequelae, the frequency of occurrence, and the implications associated with on- and off-target cutaneous toxicities of inhibitors acting at the cell membrane level, chiefly inhibitors of epidermal growth factor receptor, KIT, and BCR-ABL, angiogenesis, and multikinase inhibitors.
The Covid-19 pandemic threatens to overwhelm scarce clinical resources. Risk factors for severe illness must be identified to make efficient resource allocations.
To evaluate risk factors for severe ...illness.
Retrospective, observational case series.
Single-institution.
First 117 consecutive patients hospitalized for Covid-19 from March 1 to April 12, 2020.
None.
Intensive care unit admission or death.
In-hospital mortality was 24.8% and average total length of stay was 11.82 days (95% CI: 10.01 to 13.63 days). 30.8% of patients required intensive care unit admission and 29.1% required mechanical ventilation. Multivariate regression identified the amount of supplemental oxygen required at admission (OR: 1.208, 95% CI: 1.011-1.443, p = .037), sputum production (OR: 6.734, 95% CI: 1.630-27.812, p = .008), insulin dependent diabetes mellitus (OR: 11.873, 95% CI: 2.218-63.555, p = .004) and chronic kidney disease (OR: 4.793, 95% CI: 1.528-15.037, p = .007) as significant risk factors for intensive care unit admission or death. Of the 48 patients who were admitted to the intensive care unit or died, this occurred within 3 days of arrival in 42%, within 6 days in 71%, and within 9 days in 88% of patients.
At our regional medical center, patients with Covid-19 had an average length of stay just under 12 days, required ICU care in 31% of cases, and had a 25% mortality rate. Patients with increased sputum production and higher supplemental oxygen requirements at admission, and insulin dependent diabetes or chronic kidney disease may be at increased risk for severe illness. A model for predicting intensive care unit admission or death with excellent discrimination was created that may aid in treatment decisions and resource allocation. Early identification of patients at increased risk for severe illness may lead to improved outcomes in patients hospitalized with Covid-19.
An orange‐red organic light‐emitting diode containing a heptazine derivative exhibits high performance with a maximum external quantum efficiency of 17.5 ± 1.3% and a peak luminance of 17000 ± 1600 ...cd m−2 without any light out‐coupling enhancement. The high electroluminescence performance can be ascribed to the presence of an efficient up‐conversion channel from the lowest triplet state to the lowest singlet state.
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