Spectral mapping of brain functional connectivity from diffusion imaging.

Understanding the relationship between the dynamics of neural processes and the anatomical substrate of the brain is a central question in neuroscience. On the one hand, modern neuroimaging technologies, such as diffusion tensor imaging, can be used to construct structural graphs representing the architecture of white matter streamlines linking cortical and subcortical structures. On the other hand, temporal patterns of neural activity can be used to construct functional graphs representing temporal correlations between brain regions. Although some studies provide evidence that whole-brain functional connectivity is shaped by the underlying anatomy, the observed relationship between function and structure is weak, and the rules by which anatomy constrains brain dynamics remain elusive. In this article, we introduce a methodology to map the functional connectivity of a subject at rest from his or her structural graph. Using our methodology, we are able to systematically account for the role of structural walks in the formation of functional correlations. Furthermore, in our empirical evaluations, we observe that the eigenmodes of the mapped functional connectivity are associated with activity patterns associated with different cognitive systems

Lorenza Böttner: Requiem for the Norm

"Lorenza Böttner: Requiem for the Norm, curated by philosopher Paul B. Preciado is the first major monographic survey of Chilean/German artist Lorenza Böttner’s lifework. A trans person without arms, Böttner worked in painting, dance, performance, photography and installation to generate a body of work that celebrated her standpoint and gender expression, resolutely transgressing and refusing any and all ableist and gender-normative prescriptions. Over sixteen years she produced more than two hundred works working with her mouth and feet and performing in the public arena of the street. The exhibition presents her work along with documentary videos as well as correspondence and photographs from her archive." -- Publisher's website

Prótese, mon amor

Tradução do texto "Prótesis, mon amour", de Paul B. Preciado. Publicado nos "Anexos" do livro "Manifiesto contrasexual", 2000, Barcelona: Editorial Anagrama. Paul B. Preciado é um filósofo trans español; foi aluno de Jacques Derrida e é professor na Universidade de Paris VIII. Desde o início do século tem contribuido com os estudos queer e escreveu alguns livros como "Testo yonqui", "Pornotopía: arquitectura y sexualidad en 'Playboy' durante la guerra fría" e "Un apartamento en Urano". Pouquíssimos textos seus estão traduzidos ao português

Combined electrical transport and capacitance spectroscopy of a MoS2−LiNbO3{\mathrm{MoS_2-LiNbO_3}} field effect transistor

We have measured both the current-voltage ($I_\mathrm{SD}$-$V_\mathrm{GS}$) and capacitance-voltage ($C$-$V_\mathrm{GS}$) characteristics of a $\mathrm{MoS_2-LiNbO_3}$ field effect transistor. From the measured capacitance we calculate the electron surface density and show that its gate voltage dependence follows the theoretical prediction resulting from the two-dimensional free electron model. This model allows us to fit the measured $I_\mathrm{SD}$-$V_\mathrm{GS}$ characteristics over the \emph{entire range} of $V_\mathrm{GS}$. Combining this experimental result with the measured current-voltage characteristics, we determine the field effect mobility as a function of gate voltage. We show that for our device this improved combined approach yields significantly smaller values (more than a factor of 4) of the electron mobility than the conventional analysis of the current-voltage characteristics only.Comment: to appear in Applied Physics Letter

Parametric and sensitivity analysis for a proposed filtered tailings storage facility in challenging topography

Parametric and sensitivity analyses were performed for a proposed filtered tail- ings storage facility in challenging topography from the Southern Peru region. The purpose was to identify elements which are likely to dictate performance and stability, and to understand the risk profile for the facility. The analyses were performed varying: foundation material physical and hydraulic properties, tailings physical and hydraulic properties, foundation configuration, seismicity, and staged construction. The physical properties of the foundation material were varied by changing the Mohr-Coulomb strength parameters c’ and φ’, whereas the hydraulic properties were varied by moving the groundwater table upwards or saturating a larger amount of the foundation material. A similar approach was adopted in order to vary the physical and hydraulic properties of the tailings. The foundation configuration was varied by hypothetically moving the starter buttress closer to the edge of steep slopes further downhill from the facility. Staged construction stability analyses were simulated by analyzing filtered tailings fill configurations, which followed the overall design slope but varied in height. All analyses presented herein were conducted for the most critical failure mode for each scenario. The results from these parametric analyses showed that the design of the facility was highly sensitive to tailings potential saturation. In the simulation scenarios, saturation of the tailings caused instability in both static and seismic conditions. This sensitivity to moisture conditions highlighted the importance of properly defining the unsaturated filtered tailings parameters and simulating water infiltration processes through the vadose zone.Fil: Preciado, H. F. AMEC S.A; Perú.Fil: Ale, J. AMEC S.A; Perú.Fil: Byler, B. AMEC Englewood; USA.Fil: Perez, F. AMEC S.A; Perú.Fil: Mejía, V. AMEC S.A; Perú.Fil: McIver, D. Minera IRL SA; Perú.Otras Ingeniería Civi

Translucent perovskite photovoltaics for building integration

Transparent photovoltaics provide diverse levels of average visible transmittance (AVT) along with concurrent light harvesting, making glass façades and windows accessible for photovoltaics. However, improvements in power conversion efficiency (PCE) and aesthetics are required to enhance commercial viability and public acceptance. This work presents the scalable fabrication of efficient micro-patterned translucent perovskite photovoltaics at optical qualities suited for building integration. Optimized laser-scribed transparent areas (25 μm) mitigate detrimental effects on electrical performance, featuring perovskite solar cells with 44% AVT and demonstrating industrial glass quality through neutral color rendering (CRI 97) and only 3% haze. Highlighting scalability, submodules yield PCEs of 9.0% at 32% AVT (4 cm2 aperture area). The transfer to two-terminal perovskite–perovskite tandem solar cells exhibiting PCEs of 17.7% at 12% AVT and 11.1% at 31% AVT demonstrates the first translucent perovskite tandem photovoltaics. Lastly, the novel concept of transmittance gradients with 7% cm−1 absolute change in AVT and 12.0% PCE for submodules is presented, providing a foundation for architectural individualizations

Is juvenile anchovy a feeding resource for the demersal community in the Bay of Biscay? On the availability of pelagic prey to demersal predators

The role that juvenile anchovy (Engraulis encrasicolus) play as a food resource for the demersal community in the southern Bay of Biscay is assessed using 21 years of anchovy abundance data and demersal predator diets. During the study period, a total of 26 fish and elasmobranch species preyed on anchovy either frequently or occasionally. Predators with a crustacean-based diet targeted the smaller anchovy individuals. The size range of anchovy juveniles (centred at 7.5–8.9 cm) was comparable to that of the largest nektonic–benthic crustaceans, but generally smaller than other demersal and pelagic fish prey. Hake (Merluccius merluccius) and megrim (Lepidorhombus whiffiagonis) were the predators that consumed the highest number of anchovy, one of the main prey items driving the variability of their diets. Anchovy consumption conformed only partially to the abundance of anchovy in the southern Bay of Biscay, suggesting that factors other than abundance might condition its availability to demersal predators. Prey size could be one of them, as the size of the anchovy preyed on proved to be significantly smaller than the individuals collected with bottom trawls. However, other factors, such as the vertical position of the shoals of anchovy juveniles, could also constrain anchovy availability to demersal predators

Analysis and classification of the breathing pattern in patients on weaning trial process

La estimación del momento óptimo de retirar la ventilación asistida de un paciente en cuidado intensivo sigue siendo fundamental en la práctica clínica. En este trabajo se estudia el patrón respiratorio a partir de la señal de flujo respiratorio de pacientes en proceso de extubación teniendo en cuenta las siguientes etapas: caracterización de la señal a partir de la identificación de los ciclos respiratorios, análisis del patrón respiratorio a partir del modelado matemático de las series, y clasificación del mismo con el objetivo de identificar patrones de pacientes con posible éxito en el proceso. Se analizaron 153 pacientes clasificados en los grupos éxito, fracaso y reintubados, de acuerdo con el resultado de la prueba de extubación de tubo en T. Se seleccionaron las series temporales de tiempo de espiración, tiempo de inspiración, duración del ciclo respiratorio e índice de respiración superficial dado que presentaron diferencias significativas en los parámetros de valor medio, orden del modelo, primer coeficiente y error final de predicción. Con ellas se obtuvo una exactitud de clasificación del 86% (sensibilidad 0,86 – especificidad 0,84) utilizando un clasificador tipo discrimante lineal. Se analizaron otros clasificadores como regresión logística y máquinas de soporte vectorial.Estimating the optimal time to remove the ventilatory support from a patient in intensive care remains essential in clinical practice. In this work we study the breathing pattern from the respiratory flow signal in the process of weaning considering the following stages: characterization of the signal from the identification of respiratory cycles, respiratory pattern analysis from mathematical modeling of the resulting series, and classification in order to identify patterns of patients with possible success in the process. We analyzed 153 patients classified into three groups: success, failure and reintubated, according to results of T-tube test. The time series for breathing duration, inspiratory time, expiratory time, and shallow breathing index that resulted in significant differences in the mean, model order, first coefficient and final error of prediction were selected. With them we obtained a classification accuracy of 86% (sensitivity 0.84 - specificity 0.86) using a linear classifier discriminate type. Other classifications were analyzed, such as logistic regression and support vector machines