4,685 research outputs found
Momentum-resolved lattice dynamics of parent and electron-doped SrIrO
The mixing of orbital and spin character in the wave functions of the
iridates has led to predictions of strong couplings among their lattice,
electronic and magnetic degrees of freedom. As well as realizing a novel
spin-orbit assisted Mott-insulating ground state, the perovskite iridate
SrIrO has strong similarities with the cuprate LaCuO,
which on doping hosts a charge-density wave that appears intimately connected
to high-temperature superconductivity. These phenomena can be sensitively
probed through momentum-resolved measurements of the lattice dynamics, made
possible by meV-resolution inelastic x-ray scattering. Here we report the first
such measurements for both parent and electron-doped SrIrO. We find
that the low-energy phonon dispersions and intensities in both compounds are
well described by the same nonmagnetic density functional theory calculation.
In the parent compound, no changes of the phonons on magnetic ordering are
discernible within the experimental resolution, and in the doped compound no
anomalies are apparent due to charge-density waves. These measurements extend
our knowledge of the lattice properties of (SrLa)IrO
and constrain the couplings of the phonons to magnetic and charge order.Comment: 8 pages, 6 figures (+ 12 pages, 6 figures of supplemental material
Crossover from 2D to 3D in a weakly interacting Fermi gas
We have studied the transition from two to three dimensions in a low
temperature weakly interacting Li Fermi gas. Below a critical atom number,
, only the lowest transverse vibrational state of a highly anisotropic
oblate trapping potential is occupied and the gas is two-dimensional. Above
the Fermi gas enters the quasi-2D regime where shell structure
associated with the filling of individual transverse oscillator states is
apparent. This dimensional crossover is demonstrated through measurements of
the cloud size and aspect ratio versus atom number.Comment: Replaced with published manuscrip
Health-related quality of life and psychological features in post-stroke patients with chronic pain: A cross-sectional study in the neuro-rehabilitation context of care
This study aims at exploring disability, health-related quality of life (HrQoL), psychological distress, and psychological features in post-stroke patients with chronic pain. An observational cross-sectional study involving 50 post-stroke patients (25 with chronic pain and 25 without pain) was conducted. The primary outcome was the self-reported level of disability and HrQoL which were both assessed through the Stroke Impact Scale 3.0. Both psychological distress and specific psychological features (i.e., self-efficacy, coping strategies, psychological flexibility, perceived social support) were examined. Post-stroke patients with chronic pain reported statistically significant higher levels of disability and worse HrQoL, higher psychological distress and inflexibility, as well as a lower level of self-efficacy and problem-oriented coping strategies than patients without pain (p < 0.001). Finally, correlation analysis in the group of stroke survivors with pain showed that higher levels of disability were significantly related to higher psychological distress. This study con-firms the negative influence of chronic pain on disability and HrQoL in post-stroke patients and presents preliminary insights on the association between chronic pain, disability, HrQoL, psychosocial distress, and the patient’s approach in dealing with personal difficulties and emotions. These findings carry further implications for multidisciplinary management of post-stroke patients with chronic pain
Seleção genômica ampla para os componentes da eficiência no uso de fósforo em milho.
O objetivo deste trabalho foi verificar a eficácia do método da seleção genomica ampla (GWS) no melhoramentode milho para os componentes da eficiência no uso de fósforo (EUP). Para isto, foram avaliadas 41 combinações híbridas de milho, em alta e baixa disponibilidade de P, em casa de vegetação pertencente ao Departamento de Fitotecnia da Universidade Federal de Viçosa, em outubro de 2010. As plantas foram coletadas no estádio V6. Foram estimados os dois componentes da EUP, que são as eficiências de absorção e de utilização de N. Os dados obtidos foram submetidos a análises estatísticas via metodologia REML/BLUP. Na genotipagem da população de estimação, foram utilizados 80 marcadores microssatélites (SSR). A predição dos valores genéticos genômicos dos híbridos foi obtida via RR-BLUP/GWS. Para os caracteres em que a GWS apresentou altos valores de acurácia seletiva, ela foi comparada com a seleção recorrente intrapopulacional. Com o uso da GWS houve um aumento significativo na acurácia seletiva, nos ganhos estimados por unidade de tempo
MHz Unidirectional Rotation of Molecular Rotary Motors
A combination of cryogenic UV-vis and CD spectroscopy and transient absorption spectroscopy at ambient temperature is used to study a new class of unidirectional rotary molecular motors. Stabilization of unstable intermediates is achieved below 95 K in propane solution for the structure with the fastest rotation rate, and below this temperature measurements on the rate limiting step in the rotation cycle can be performed to obtain activation parameters. The results are compared to measurements at ambient temperature using transient absorption spectroscopy, which show that behavior of these motors is similar over the full temperature range investigated, thereby allowing a maximum rotation rate of 3 MHz at room temperature under suitable irradiation conditions
Tecnologias Embrapa para a cultura da mamoneira.
bitstream/item/57750/1/Folder-Cultivares-de-Mamona-da-Embrapa-Algodao.pd
Efeito da concentração de sacarose na germinação in vitro do pólen de cinco acessos de bacurizeiro (Platonia insignis Mart.).
O bacurizeiro é uma das espécies fruteiras nativas de maior importância socioeconômica das regiões Norte e Meio-Norte do Brasil. No entanto, ainda há carência de conhecimentos científicos sobre a espécie, especialmente sobre sua biologia floral, mecanismos reprodutivos e viabilidade do pólen. O conhecimento sobre a viabilidade do pólen é fundamental para o melhoramento genético, especialmente quando se tem em mente a realização de hibridizações controladas. O objetivo deste trabalho foi avaliar o efeito da sacarose e de acessos na viabilidade do pólen de bacurizeiro por meio da germinação in vitro
Unidade de intervenção técnica: uma estratégia de difusão e transferência de tecnologia para o pequeno agricultor.
Percepcao do agricultor versus adocao de inovacoes; Transferencia de tecnologia versus adocao; modelo de difusao utilizado pela Embrapa Algodao, na transferencia de tecnologia; Estrategia operacional;: Principais resultados.bitstream/item/33386/1/UNIDADE-DE-INTERVENCAO.pd
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