Subjective Beat Perception in Musical Rhythms in Adult Listeners

Synchronization to rhythmic stimuli is an everyday experience, whether it is exercising to the beat of music, dancing salsa, or rocking a baby to sleep. Commonly, humans synchronize their movements with the frequency of the beat (a quasi-isochronous pattern of prominent time points). Previous research has shown that the intended beat periodicity of a rhythmic stimulus can be observed in periodic neural activity; however, the extent to which this reflects robust perception of musical rhythm versus purely stimulus-driven activity is unknown. In Experiment 1 and 2, I investigated how long listeners can maintain a percept of the beat once the stimulus evidence becomes beat-ambiguous. In Experiment 3, I used electroencephalography (EEG) to investigate whether steady state-evoked potentials (SS-EPs, the electrocortical activity from a population of neurons resonating at the frequency of a periodic stimulus) arising from auditory cortex reflect beat perception when the physical information in the stimulus is ambiguous and supports two possible beat patterns. In both experiments, participants listened to a musical excerpt that strongly supported a particular beat pattern (context), followed by an ambiguous rhythm consistent with either beat pattern (ambiguous phase). During the final probe phase, listeners indicated whether a superimposed drum matched the beat. We found that participants perceived probes that matched the beat of the context as better fitting the ambiguous rhythm, compared to probes that did not match the beat of the context. We also found that SS-EPs during the ambiguous phase had higher amplitudes at frequencies corresponding to the beat of the preceding context. These findings support the idea that SS-EPs arising from auditory cortex reflect perception of musical rhythm and not just stimulus encoding of temporal features

Accurate Ritz wavelengths of parity-forbidden [Fe II], [Ti II] and [Cr II] infrared lines of astrophysical interest

With new astronomical infrared spectrographs the demands of accurate atomic data in the infrared have increased. In this region there is a large amount of parity-forbidden lines, which are of importance in diagnostics of low-density astrophysical plasmas. We present improved, experimentally determined, energy levels for the lowest even LS terms of Fe II, Ti II and Cr II, along with accurate Ritz wavelengths for parity-forbidden transitions between and within these terms. Spectra of Fe II, Ti II and Cr II have been produced in a hollow cathode discharge lamp and acquired using high-resolution Fourier Transform (FT) spectrometry. The energy levels have been determined by using observed allowed ultraviolet transitions connecting the even terms with upper odd terms. Ritz wavelengths of parity-forbidden lines have then been determined. Energy levels of the four lowest Fe II terms (a$^{6}$D, a$^{4}$F, a$^{4}$D and a$^{4}$P) have been determined, resulting in 97 different parity-forbidden transitions with wavelengths between 0.74 and 87 micron. For Ti II the energy levels of the two lowest terms (a$^{4}$F and b$^{4}$F) have been determined, resulting in 24 different parity-forbidden transitions with wavelengths between 8.9 and 130 micron. Also for Cr II the energy levels of the two lowest terms (a$^{6}$S and a$^{6}$D) have been determined, in this case resulting in 12 different parity-forbidden transitions with wavelengths between 0.80 and 140 micron.Comment: Accepted for publication in A&A, 13 pages, 6 figures, 9 table

Transport Properties of a spinon Fermi surface coupled to a U(1) gauge field

With the organic compound $\kappa$-(BEDT-TTF)$_2$-Cu$_2$(CN)$_3$ in mind, we consider a spin liquid system where a spinon Fermi surface is coupled to a U(1) gauge field. Using the non-equilibrium Green's function formalism, we derive the Quantum Boltzmann Equation (QBE) for this system. In this system, however, one cannot a priori assume the existence of Landau quasiparticles. We show that even without this assumption one can still derive a linearized equation for a generalized distribution function. We show that the divergence of the effective mass and of the finite temperature self-energy do not enter these transport coefficients and thus they are well-defined. Moreover, using a variational method, we calculate the temperature dependence of the spin resistivity and thermal conductivity of this system.Comment: 12 page

Grazing Corn Produced Under Living Mulch Systems in Tennessee

The use of living mulch (LM) in the Southeastern U.S. has yet to be assessed for its potential for grazing operations to increase land use efficiency. Therefore, the need to determine the viability of the system is warranted. The objective of this study was to evaluate the benefits of white clover LM and crimson-clover cereal rye annual mulch in corn silage and grain production, and to evaluate the potential of LM grazing before and after the corn growing season in spring and fall. The study was conducted at the Middle Tennessee AgResearch and Education Center (MTREC), University of Tennessee, in Spring Hill, TN (35.68o N, 86.91o W, 810 ft altitude), from October 2018 to April 2021. The experimental design was comprised of 12 large paddocks (0.7 ha-1). Paddocks were arranged in a complete randomized design (CRD) in triplicate, totaling 12 plots (2 corn treatments x 2 cover crop treatments x 3 replicates). The paddocks contained either corn silage or grain, grown with either perennial “Durana” white clover (Trifolium repens L.) [WC] or with a mixture of crimson clover (“AU Sunrise” Trifolium incarnatum L.) and cereal rye (“Wintergrazer” Secale cereale L.) [CCCR]). Grazing was performed in spring and fall of 2020 and 2021 before and after corn planting and harvest, respectively. In spring of both years, the LM proportion was greater in CCCR than WC, and a greater proportion of broadleaf weeds (BLW) were observed in WC. In the fall of 2020, LM proportion was greater in WC than CCCR, but no differences were observed in the fall of 2021. Meanwhile, the greatest MM was observed in WC at the beginning of the grazing period. White clover can reduce weed pressure under grazing systems. White clover as a LM also showed positive applications in grazing systems with greater MM

A decision support system framework to track consumer sentiments in social media

With the evolution of web 2.0 and social networks, customers and companies’ online interaction is growing at a fast pace, containing valuable insights about consumers’ expectations that should be monitored and explored in a day-to-day basis. However, such information is highly unstructured and difficult to analyze. There is an urgent need to set up transparent methods and processes to integrate such information in the tourism industry technological infrastructure, especially for small firms that are unable to pay for expensive services to monitor their online reputation. The current paper uses a text mining and sentimental analysis technique to structure online reviews and present them on a decision support system with two different dashboards to assist in decision-making. Such system may help managers develop new insights and strategies aligned with consumers’ expectations in a much more flexible and sustainable pace.info:eu-repo/semantics/acceptedVersio

Sedimentos marinhos : caracterização química expedita por espectrometria de fluorescência de raios X = Marine sediments : an easy-and-quick chemical characterization through X-ray fluorescence spectrometry

Com o objectivo de obter dados químicos sobre sedimentos marinhos em tempo reduzido e por uma via expedita, desenvolveu-se uma metodologia analítica baseada em espectrometria de fluorescência de raios X por dispersão em comprimentos de onfa (FRX-DCO). Descreve-se esta metodologia expedita não destrutiva e apresentam-se os primeiros resultados relativos a uma secção de uma sondagem de sedimentos marinhos, testados com sucesso por comparação com dados obtidos por uma técnica analítica de aplicação corrente