Magnon-Phonon Quantum Correlation Thermometry

A large fraction of quantum science and technology requires low-temperature environments such as those afforded by dilution refrigerators. In these cryogenic environments, accurate thermometry can be difficult to implement, expensive, and often requires calibration to an external reference. Here, we theoretically propose a primary thermometer based on measurement of a hybrid system consisting of phonons coupled via a magnetostrictive interaction to magnons. Thermometry is based on a cross-correlation measurement in which the spectrum of back-action driven motion is used to scale the thermomechanical motion, providing a direct measurement of the phonon temperature independent of experimental parameters. Combined with a simple low-temperature compatible microwave cavity readout, this primary thermometer is expected to become a promising alternative for thermometry below 1 K

Características do solo e de pastagens em sistemas de produção leiteira em Uruará, Pará.

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Efeito das auxinas 2,4-D e TDZ na indução da embriogênese somática em Uncaria tomentosa a partir de ápice caulinar.

O objetivo desse trabalho foi avaliar o efeito das auxinas 2,4-D e TDZ na indução da embriogênese somática utilizando ápice caulinar de U. tomentosa

Embriogênese somática em Uncaria tomentosa a partir de folhas imaturas.

O objetivo desse trabalho foi induzir a embriogênese somática a partir de folhas imaturas de U. tomentosa de plântulas germinadas in vitro

Nanoscale NEXAFS for Probing TiO2 B Nanoribbons

TiO2 nanostructures exist in different crystallographic phases including brookite, anatase, rutile, and TiO2 amp; 8722;B bronze . Among these, due to its open channel like crystal structure which can enhance ion mobility, the TiO2 amp; 8722;B phase has been reported as an optimal anode material for lithium ion batteries, particularly in the form of nanowires [1]. In view of device applications, where different phases may coexist and TiO2 amp; 8722;B particles may transform to the thermodynamically stable anatase phase, it is important to identify and understand the structural and electronic differences between these two phases. Here we have studied the electronic structure of TiO2 nanoribbons in TiO2 amp; 8722;B and anatase phases using polarization dependent near edge X ray absorption fine structure spectroscopy NEXAFS in the transmission X ray microscope TXM and density functional theory DFT [2,3]. NEXAFS at both the O K edge and the Ti L edge is very sensitive to the local bonding environment in TiO2 based materials and thus provides diagnostic information about the crystal structures and oxidation states. We report the observation of strong linear dichroism in the O K edge spectra of single TiO2 amp; 8722;B nanoribbons. Using DFT calculations we show that the dichroism is a consequence of the directional Ti amp; 8722;O bonding in the monoclinic crystal structur

Endocast of the Late Triassic (Carnian) dinosaur Saturnalia tupiniquim: implications for the evolution of brain tissue in Sauropodomorpha

The evolutionary history of dinosaurs might date back to the first stages of the Triassic (c. 250-240 Ma), but the oldest unequivocal records of the group come from Late Triassic (Carnian -c. 230 Ma) rocks of South America. Here, we present the first braincase endocast of a Carnian dinosaur, the sauropodomorph Saturnalia tupiniquim, and provide new data regarding the evolution of the floccular and parafloccular lobe of the cerebellum (FFL), which has been extensively discussed in the field of palaeoneurology. Previous studies proposed that the development of a permanent quadrupedal stance was one of the factors leading to the volume reduction of the FFL of sauropods. However, based on the new data for S. tupiniquim we identified a first moment of FFL volume reduction in non-sauropodan Sauropodomorpha, preceding the acquisition of a fully quadrupedal stance. Analysing variations in FFL volume alongside other morphological changes in the group, we suggest that this reduction is potentially related to the adoption of a more restricted herbivore diet. In this context, the FFL of sauropods might represent a vestigial trait, retained in a reduced version from the bipedal and predatory early sauropodomorphs