Adubação nitrogenada e idade de corte na produção de matéria seca do capim-elefante no Cerrado

Propôs-se, com este trabalho, avaliar o efeito da aplicação de N e da idade de corte na produção de biomassa e acúmulo de nitrogênio pelo capim-elefante. O experimento foi realizado com o capim-elefante cv. Paraíso, cultivado em um Latossolo Vermelho-Amarelo distrófico, município de Gurupi, TO, safra 2008/2009. Foram testadas quatro doses de N-uréia (0, 50, 100 e 150 kg ha-1) e três idades de corte do capim (120, 150 e 180 dias após o brotamento). Avaliou-se, em cada idade de corte, a produção de matéria seca da parte aérea (folhas e colmos) e o acúmulo de N na planta. A produção de matéria seca do capim-elefante aumentou com a adição de N porém o efeito foi maior para as plantas cortadas com 180 dias de idade. Encontrou-se um incremento linear na acumulação de matéria seca (R² = 0,75**) e na acumulação de N (R² = 0,96**), permitindo uma produtividade de 34 t ha-1 de matéria seca, que implicou em uma extração de N de 471 kg ha-1. A eficiência de utilização do N pela cultura variou com o aumento da idade da planta, o que significou maior quantidade de biomassa por unidade de N absorvido. O índice de eficiência mostra que o corte tardio pode favorecer a qualidade da biomassa para fins energéticos, por se tratar de um material mais fibroso.The objective of this study was to investigate the effect of the application of N fertilizer and the cutting age on the dry biomass production of elephant grass. The experiment was performed with the variety Paraíso and planted in a Ferralsol in 2008 in the district of Gurupi (State of Tocantins). Four different rates of urea application were tested (0, 50, 100 and 150 kg ha-1) and harvests were made at 120, 150 or 180 days after germination (DAG) of the setts. The dry matter and total N accumulation were evaluated. Dry matter production increased with dose of N, the greatest effect being observed at 180 DAG. There was a linear increase in dry matter (R² = 0.75**) and N accumulation (R² = 0.96**) permitting a productivity of 34 t ha-1 of dry matter and an accumulation of 471 kg N ha-1. The N utilization efficiency (biomass production per unit of applied N) increased with plant age. The higher efficiency of N use favored the quality of biomass production for energy production owing to the higher fibre content

From the lab to the clinic:Advancing pain exposure using principles of functional analysis

In this article, we use the example of pain exposure therapy to illustrate how behavioral pain treatments can be systematically personalized following the principles of functional analysis. Based on the fear-avoidance model, pain exposure therapy has evolved as a mechanistically-based treatment to modify the mechanism of avoidance learning with the aim to reduce disability levels. We first present experimental evidence on avoidance learning from a general psychological perspective. We then illustrate how functional analysis can help therapists understand and address individual drivers of pain avoidance behavior. Finally, we explore how the network theory can translate the principles of functional analysis into statistical parameters using intensive longitudinal data, potentially making exposure experiments more relevant to the daily lives of individuals

Cubic ZnXMg1-XO Thin Films Grown By Plasma-Assisted Molecular-Beam Epitaxy For Optoelectronic Applications

Heteroepitaxial ZnxMg1-xO thin films were grown on lattice-matched MgO (100) substrates using radiofrequency plasma-assisted molecular-beam epitaxy. High-quality epilayers with zinc concentrations ranging from x = 0 (MgO) to x = 0.65 were grown and characterized optically, structurally, and electrically. The ZnxMg1-xO films were found to maintain the rocksalt cubic (81) crystal structure for concentrations z \u3c0.65, with a linear dependence of lattice constant on Zn concentration. X-ray diffraction (XRD) also revealed the emergence of phase segregation into wurtzite (54) phase for the highest concentration film. The band gap energy of the films was successfully varied from 4.9 to 6.2 eV (253-200 nm), showing a linear relationship with Zn concentration. The strictly cubic films exhibit roughness on the order of 10 Å and resistivities of approximately 10 6 ω.cm. © 2010 Materials Research Society

Negative Emotion Differentiation Attenuates the Within-Person Indirect Effect of Daily Stress on Nightly Sleep Quality Through Calmness

The ability to differentiate between negative emotional states [negative emotion differentiation (NED)] has been conceptualized as a trait that facilitates effective emotion regulation and buffers stress reactivity. In the present research, we investigated the role of NED in within-person processes of daily affect regulation and coping during times of stress (the first COVID-19-related pandemic lockdown in April 2020). Using intensive longitudinal data, we analyzed whether daily stress had an indirect effect on sleep quality through calmness in the evening, and we tested whether NED moderated this within-person indirect effect by buffering the link between daily stress and calmness in the evening. A non-representative community sample (n = 313, 15–82 years old) participated in a 21-day ambulatory assessment with twice-daily surveys. The results of multilevel mediation models showed that higher daily stress was related to within-day change in calmness from morning to evening, resulting in less calmness in the evening within persons. Less calmness in the evening, in turn, was related to poorer nightly sleep quality within persons. As expected, higher NED predicted a less negative within-person link between daily stress and calmness in the evening, thereby attenuating the indirect effect of daily stress on nightly sleep quality through calmness. This effect held when we controlled for mean negative emotions and depression. The results provide support for a diathesis-stress model of NED, and hence, for NED as a protective factor that helps to explain why some individuals remain more resilient during times of stress than others.</jats:p