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The wrinkle pattern exhibited upon stretching a rectangular sheet has attracted considerable interest in the “extreme mechanics” community. Nevertheless, key aspects of this notable phenomenon remain elusive. Specifically-what is the origin of the compressive stress underlying the instability of the planar state? what is the nature of the ensuing bifurcation? how does the shape evolve from a critical, near-threshold regime to a fully developed pattern of parallel wrinkles that permeate most of the sheet? In this paper we address some of these questions through numerical simulations and analytic study of the planar state in Hookean sheets. We show that transverse compression is a boundary effect, which originates from the relative extension of the clamped edges with respect to the transversely contracted, compression-free bulk of the sheet, and draw analogy between this edge-induced compression and Moffatt vortices in viscous, cavity-driven flow. Next, we address the instability of the planar state and show that it gives rise to a buckling pattern, localized near the clamped edges, which evolves-upon increasing the tensile load-to wrinkles that invade the uncompressed portion of the sheet. Crucially, we show that the key aspects of the process-from the formation of transversely compressed zones, to the consequent instability of the planar state and the emergence of a wrinkle pattern-can be understood within a Hookean framework, where the only origin of nonlinear response is geometric, rather than a non-Hookean stress-strain relation.The Subdural Hematoma in the Elderly (SHE) score was developed as a model to predict 30-day mortality from acute, chronic, and mixed subdural hematoma in the elderly population after minor or no trauma. Emerging evidence suggests frailty to be predictive of mortality and morbidity in the elderly. In this study, we aim to externally validate the SHE for chronic subdural hematoma (CSDH) alone, and we hypothesize that the incorporation of frailty into the SHE may increase its predictive power. A retrospective cohort of elderly patients with CSDH after minor or no trauma being treated at our institution was evaluated with the SHE. Thirty-day mortality and outcome were documented. Patients were assessed with the Clinical Frailty Scale (CFS), which was incorporated into a modified SHE (mSHE). Both the SHE and the mSHE were then assessed in their predictive powers through receiver operating characteristic statistics. We included 168 patients. Most (n = 124, 74%) had a favorable outcome at 30 days. Mortality was low at n = 7, 4%. The SHE failed to predict mortality (AUC = .564, p = .565). Contrarily, the mSHE performed well in both mortality (AUC = .749, p = .026) and outcome (AUC = .862, p  less then  .001). A threshold of mSHE = 3 is predictive of mortality with a sensitivity of 50% and a specificity of 75% and of poor outcome with a sensitivity of 88% and a specificity of 64%. Frailty should be routinely evaluated in elderly individuals, as it can predict outcome and mortality, providing the possibility for medical, surgical, nutritional, cognitive, and physical exercise interventions.Superstitions and the placebo effect have each been found to influence human behaviour. The present study aimed to determine whether there is a relationship between superstition and the placebo effect, and whether this relationship affects human cognition and behaviour. We hypothesized that more superstitious people would be more prone to the placebo effect and that it would improve their performance on cognitive tasks. Results showed that in the placebo condition, more superstitious people memorized more words than less superstitious people. ALKBH5 inhibitor 2 cost However, in the control condition, less superstitious people memorized more words than more superstitious people. Overall, the findings supported our hypothesis. The findings of the study are important, as they draw a link between the placebo effect and superstition, and further show that these two elements impact human performance in cognitive ability tasks.As part of this Special Issue of International Microbiology celebrating the 75th anniversary of the founding of the Spanish Society for Microbiology (SEM), Guest Editor Rafael Giraldo invited us to contribute an opinion article on the topic of 75 years of joint scientific ventures between Latin American microbiologists and Spanish microbiologists. Since the creation of SEM in 1945 (Pérez Prieto, NoticiaSEM 981, 2016) Latin American microbiologists have been participants, both as individuals and as members of the national associations that are currently integrated into the Latin American Association for Microbiology (ALAM). Thus, the histories of Spanish and Latin American microbiology (Chica and Skinner, Int Microbiol 13159-164, 2010; Chica, Int Microbiol 11221-225, 2008) have been closely linked over the last 75 years. In order to provide our perspective on the topic, we decided to provide answers to three questionsWhat are key aspects of the history of Spanish and Latin American Microbiology interactions? What have been some of our personal experiences in which these interactions shaped our careers? What is our outlook for the future of such interactions?

Sleep apnea-hypopnea syndrome (SAHS) is an independent risk factor for various cardiovascular and cerebrovascular diseases, but the underlying relationship of its physiological subsystems remains unclear. Thus, we aimed to investigate the effect of SAHS on central and autonomic nervous system (CNS-ANS) interactions during sleep.

Thirty-five patients with SAHS and 19 healthy age-matched controls underwent overnight polysomnography. The absolute spectral powers of five frequency bands from six EEG channels and ECG morphological features (HR, PRinterval, QTinterval) were calculated. Multivariable transfer entropy was applied to analyze the differences of the CNS-ANS network interactions between patients withSAHS of different severities and healthy controls during deep, light, and rapid eye movement sleep.

The CNS-ANS network interacted bidirectionally in all researched groups, with the cardiac information modulating the brain activity. The information strength from QT to most EEG components and PR to some EEG components was significantly affected by SAHS severity during light sleep, which indicates the coupling features of QT-brain nodes are important indicators.