Simultaneous consonance is a salient perceptual phenomenon corresponding to the perceived pleasantness of simultaneously sounding musical tones. Various competing theories of consonance have been ...proposed over the centuries, but recently a consensus has developed that simultaneous consonance is primarily driven by harmonicity perception. Here we question this view, substantiating our argument by critically reviewing historic consonance research from a broad variety of disciplines, reanalyzing consonance perception data from 4 previous behavioral studies representing more than 500 participants, and modeling three Western musical corpora representing more than 100,000 compositions. We conclude that simultaneous consonance is a composite phenomenon that derives in large part from three phenomena: interference, periodicity/harmonicity, and cultural familiarity. We formalize this conclusion with a computational model that predicts a musical chord's simultaneous consonance from these three features, and release this model in an open-source R package, incon, alongside 15 other computational models also evaluated in this paper. We hope that this package will facilitate further psychological and musicological research into simultaneous consonance.
We experimentally demonstrate coherence recovery of singlet-triplet superpositions by interlacing qubit rotations between Carr-Purcell (CP) echo sequences. We then compare the performance of Hahn, ...CP, concatenated dynamical decoupling (CDD), and Uhrig dynamical decoupling for singlet recovery. In the present case, where gate noise and drift combined with spatially varying hyperfine coupling contribute significantly to dephasing, and pulses have limited bandwidth, CP and CDD yield comparable results, with T(2)∼80 μs.
The superconductor–insulator transition in two dimensions has been widely investigated as a paradigmatic quantum phase transition. The topic remains controversial because many experiments exhibit a ...metallic regime with saturating low-temperature resistance, which is at odds with conventional theory. Here, we explore this transition in a highly controllable system, a semiconductor heterostructure with epitaxial aluminium, patterned to form a regular array of superconducting islands connected by a gateable quantum well. Spanning nine orders of magnitude in resistance, the system exhibits regimes of superconducting, metallic and insulating behaviour, along with signatures of flux commensurability and vortex penetration. An in-plane magnetic field eliminates the metallic regime, restoring the direct superconductor–insulator transition; it also improves the scaling behaviour while strongly altering the scaling exponent.
We have measured carbon nanotube quantum dots with multiple electrostatic gates and used the resulting enhanced control to investigate a nanotube double quantum dot. Transport measurements reveal ...honeycomb charge stability diagrams as a function of two nearly independent gate voltages. The device can be tuned from weak to strong interdot tunnel-coupling regimes, and the transparency of the leads can be controlled independently. We extract values of energy-level spacings, capacitances, and interaction energies for this system. This ability to control electron interactions in the quantum regime in a molecular conductor is important for applications such as quantum computation.
Epitaxial semiconductor-superconductor hybrid materials are an excellent basis for studying mesoscopic and topological superconductivity, as the semiconductor inherits a hard superconducting gap ...while retaining tunable carrier density. Here, we investigate double-quantum-dot structures made from InAs nanowires with a patterned epitaxial Al two-facet shell that proximitizes two gate-defined segments along the nanowire. We follow the evolution of mesoscopic superconductivity and charging energy in this system as a function of magnetic field and voltage-tuned barriers. Interdot coupling is varied from strong to weak using side gates, and the ground state is varied between normal, superconducting and topological regimes by applying a magnetic field. We identify the topological transition by tracking the spacing between successive co-tunnelling peaks as a function of axial magnetic field and show that the individual dots host weakly hybridized Majorana modes.
In 2003 and 2004, U.S. and European regulators issued public health warnings about a possible association between antidepressants and suicidal thinking and behavior. The authors assessed whether ...these warnings discouraged use of antidepressants in children and adolescents and whether they led to increases in suicide rates as a result of untreated depression.
The authors examined U.S. and Dutch data on prescription rates for selective serotonin reuptake inhibitors (SSRIs) from 2003 to 2005 in children and adolescents (patients up to age 19), as well as suicide rates for children and adolescents, using available data (through 2004 in the United States and through 2005 in the Netherlands). They used Poisson regression analyses to determine the overall association between antidepressant prescription rates and suicide rates, adjusted for sex and age, during the periods preceding and immediately following the public health warnings.
SSRI prescriptions for youths decreased by approximately 22% in both the United States and the Netherlands after the warnings were issued. In the Netherlands, the youth suicide rate increased by 49% between 2003 and 2005 and shows a significant inverse association with SSRI prescriptions. In the United States, youth suicide rates increased by 14% between 2003 and 2004, which is the largest year-to-year change in suicide rates in this population since the Centers for Disease Control and Prevention began systematically collecting suicide data in 1979.
In both the United States and the Netherlands, SSRI prescriptions for children and adolescents decreased after U.S. and European regulatory agencies issued warnings about a possible suicide risk with antidepressant use in pediatric patients, and these decreases were associated with increases in suicide rates in children and adolescents.
Purpose
Cytomegalovirus (CMV) reactivation occurs frequently in patients with the acute respiratory distress syndrome (ARDS) and has been associated with increased mortality. However, it remains ...unknown whether this association represents an independent risk for poor outcome. We aimed to estimate the attributable effect of CMV reactivation on mortality in immunocompetent ARDS patients.
Methods
We prospectively studied immunocompetent ARDS patients who tested seropositive for CMV and remained mechanically ventilated beyond day 4 in two tertiary intensive care units in the Netherlands from 2011 to 2013. CMV loads were determined in plasma weekly. Competing risks Cox regression was used with CMV reactivation status as a time-dependent exposure variable. Subsequently, in sensitivity analyses we adjusted for the evolution of disease severity until onset of reactivation using marginal structural modeling.
Results
Of 399 ARDS patients, 271 (68 %) were CMV seropositive and reactivation occurred in 74 (27 %) of them. After adjustment for confounding and competing risks, CMV reactivation was associated with overall increased ICU mortality (adjusted subdistribution hazard ratio (SHR) 2.74, 95 % CI 1.51–4.97), which resulted from the joint action of trends toward an increased mortality rate (direct effect; cause specific hazard ratio (HR) 1.58, 95 % CI 0.86–2.90) and a reduced successful weaning rate (indirect effect; cause specific HR 0.83, 95 % CI 0.58–1.18). These associations remained in sensitivity analyses. The population-attributable fraction of ICU mortality was 23 % (95 % CI 6–41) by day 30 (risk difference 4.4, 95 % CI 1.1–7.9).
Conclusion
CMV reactivation is independently associated with increased case fatality in immunocompetent ARDS patients who are CMV seropositive.
Background. Systemic reactivations of herpesviruses may occur in intensive care unit (ICU) patients, even in those without prior immune deficiency. However, the clinical relevance of these events is ...uncertain. Methods. In this study we selected patients admitted with septic shock and treated for more than 4 days from a prospectively enrolled cohort of consecutive adults in the mixed ICUs of 2 tertiary care hospitals in the Netherlands. We excluded patients who had received antiviral treatment in the week before ICU admission and those with known immunodeficiency. We studied viremia episodes with cytomegalovirus (CMV), Epstein–Barr virus (EBV), human herpesvirus 6 (HHV-6), herpes simplex virus types 1 (HSV-1) and 2 (HSV-2), and varicella zoster virus (VZV) by weekly polymerase chain reaction in plasma. Results. Among 329 patients, we observed 399 viremia episodes in 223 (68%) patients. Viremia with CMV, EBV, HHV-6, HSV-1, HSV-2, and VZV was detected in 60 (18%), 157 (48%), 80 (24%), 87 (26%), 13 (4%), and 2 (0.6%) patients, respectively; 112 (34%) patients had multiple concurrent viremia events. Crude mortality in the ICU was 36% in this latter group compared to 19% in remaining patients (P < .01). After adjustment for potential confounders, time-dependent bias, and competing risks, only concurrent CMV and EBV reactivations remained independently associated with increased mortality (adjusted subdistribution hazard ratio, 3.17; 95% confidence interval, 1.41–7.13). Conclusions. Herpesvirus reactivations were documented in 68% of septic shock patients without prior immunodeficiency and frequently occurred simultaneously. Concurrent reactivations could be independently associated with mortality. Clinical Trials Registration. NCT01905033.
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