Quantum Quench of an Atomic Mott Insulator

We study quenches across the Bose-Hubbard Mott-insulator-to-superfluid quantum phase transition using an ultra-cold atomic gas trapped in an optical lattice. Quenching from the Mott insulator to superfluid phase is accomplished by continuously tuning the ratio of Hubbard tunneling to interaction energy. Excitations of the condensate formed after the quench are measured using time-of-flight imaging. We observe that the degree of excitation is proportional to the fraction of atoms that cross the phase boundary, and that the quantity of excitations and energy produced during the quench have a power-law dependence on the quench rate. These phenomena suggest an excitation process analogous to the Kibble-Zurek (KZ) mechanism for defect generation in non-equilibrium classical phase transitions

Juggling Priorities: Female Mating Tactics in P hayre's Leaf Monkeys

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91119/1/ajp22004.pd

Variation in grouping patterns, mating systems and social structure: what socio-ecological models attempt to explain

Socio-ecological models aim to predict the variation in social systems based on a limited number of ecological parameters. Since the 1960s, the original model has taken two paths: one relating to grouping patterns and mating systems and one relating to grouping patterns and female social structure. Here, we review the basic ideas specifically with regard to non-human primates, present new results and point to open questions. While most primates live in permanent groups and exhibit female defence polygyny, recent studies indicate more flexibility with cooperative male resource defence occurring repeatedly in all radiations. In contrast to other animals, the potential link between ecology and these mating systems remains, however, largely unexplored. The model of the ecology of female social structure has often been deemed successful, but has recently been criticized. We show that the predicted association of agonistic rates and despotism (directional consistency of relationships) was not supported in a comparative test. The overall variation in despotism is probably due to phylogenetic grade shifts. At the same time, it varies within clades more or less in the direction predicted by the model. This suggests that the model's utility may lie in predicting social variation within but not across clades

Estudo de avaliação sensorial de pegajosidade de arroz.

O presente estudo consiste da análise estatística de 4 amostras diferentes de arroz irrigado com base em notas atribuídas por um painel sensorial treinado. Três avaliadores atribuíram notas de pegajosidade numa escala hedônica variando de 1 (muito pegajoso) a 7 (muito solto), em diferentes épocas. O objetivo deste trabalho foi verificar se os avaliadores eram consistentes em suas avaliações entre as amostras e entre seus pares

Vertical coupling and transport in high-latitude ionosphere

Various plasma anomalies appear at auroral latitudes, extending across the polar cap as a tongue of ionisation (TOI) and polar patches (PPs). Mechanisms responsible for horizontal and vertical plasma transport include the forcing from above (solar irradiance and geomagnetic activity) and from below (atmospheric waves and tides). The forcing mechanisms balance each other in lower thermosphere, forming the ionospheric transition region. At higher altitudes (the F layer), plasma irregularities can be transported for hours, while in the E layer and below the irregularities recombine within seconds. Incoherent (ISR) and coherent scatter radars can observe vertical coupling and dynamics at various horizontal scales, providing a tool for analysing the transition region. Modelling with GCMs provides a basis for mitigating/forecasting the space weather. Vertical coupling and transport will be addressed in connection to the drifting polar cap anomalies (TOI and PPs). Examples of the vertical coupling and transport with the EISCAT ISR will show relative contributions of the forcing from above and below. Examples of plasma irregularities seen by GNSS receiver networks and SAR radars will be also shown

Structure of the Polycomb Group Protein PCGF1 in Complex with BCOR Reveals Basis for Binding Selectivity of PCGF Homologs

SummaryPolycomb-group RING finger homologs (PCGF1, PCGF2, PCGF3, PCGF4, PCGF5, and PCGF6) are critical components in the assembly of distinct Polycomb repression complex 1 (PRC1)-related complexes. Here, we identify a protein interaction domain in BCL6 corepressor, BCOR, which binds the RING finger- and WD40-associated ubiquitin-like (RAWUL) domain of PCGF1 (NSPC1) and PCGF3 but not of PCGF2 (MEL18) or PCGF4 (BMI1). Because of the selective binding, we have named this domain PCGF Ub-like fold discriminator (PUFD). The structure of BCOR PUFD bound to PCGF1 reveals that (1) PUFD binds to the same surfaces as observed for a different Polycomb group RAWUL domain and (2) the ability of PUFD to discriminate among RAWULs stems from the identity of specific residues within these interaction surfaces. These data show the molecular basis for determining the binding preference for a PCGF homolog, which ultimately helps determine the identity of the larger PRC1-like assembly

Vertical coupling and transport in high-latitude ionosphere

Various ionospheric plasma anomalies appear at auroral latitudes, extending across the polar cap as a tongue of ionisation (TOI) and/or polar patches (PPs). Mechanisms responsible for horizontal and vertical plasma transport include the forcing from above (solar irradiance and geomagnetic activity) and from below (atmospheric waves and tides). The forcing mechanisms balance each other in mesosphere/lower thermosphere, forming the ionospheric transition region. At higher altitudes (in the F layer), plasma irregularities can be transported for hours, while below (in the E layer) the irregularities recombine within seconds. Incoherent (ISR) and coherent scatter radars can observe vertical coupling and dynamics at various horizontal scales, providing a tool for analysing the transition region. Modelling with GCMs provides a basis for mitigating/forecasting the space weather. Vertical coupling and transport will be addressed in connection to the drifting polar cap anomalies (TOI and PPs). Examples of the vertical coupling and transport with the EISCAT ISR, coherent scatter radars, and GNSS receiver networks will show relative contributions of the forcing from above and below

Determining the origin of tidal oscillations in the ionospheric transition region with EISCAT radar and global simulation data

At high-latitudes, diurnal and semidiurnal variations of temperature and neutral wind velocity can originate both in the lower atmosphere (UV or infrared absorption) or in the thermosphere-ionosphere (ion convection, EUV absorption). Determining the relative impact of different forcing mechanisms gives insight to the vertical coupling in the ionosphere. We analyse measurements from the incoherent scatter radar (ISR) facility operated by the EISCAT Scientific Association. They are complemented by meteor radar data and compared to global circulation models. The amplitudes and phases of tidal oscillations are determined by an Adaptive Spectral Filter (ASF). Measurements indicate the existence of strong semidiurnal oscillations in a two-band structure at altitudes ≲ 110 km and ≳ 130 km, respectively. Analysis of several model runs with different input settings suggest the upper band to be forced in situ while the lower band corresponds to upward-propagating tides from the lower atmosphere. This indicates the existence of an unexpectedly strong, in situ forcing mechanism for semidiurnal oscillations in the high-latitude thermosphere. It is shown that the actual transition of tides in the altitude region between 90 and 150 km is more complex than described so far

Ajuste de escalas de classificação de arroz cozido para avaliação de pegajosidade e dureza.

O objetivo deste trabalho foi ajustar e redefinir as notas e padrões da escala sensorial de classificação da textura do arroz cozido, a fim de facilitar a compreensão dos painelistas e aproximar os resultados laboratoriais da análise feita pelas indústria