Quantum Degenerate Mixture of Ytterbium and Lithium Atoms

We have produced a quantum degenerate mixture of fermionic alkali 6Li and bosonic spin-singlet 174Yb gases. This was achieved using sympathetic cooling of lithium atoms by evaporatively cooled ytterbium atoms in a far-off-resonant optical dipole trap. We observe co-existence of Bose condensed (T/T_c~0.8) 174Yb with 2.3*10^4 atoms and Fermi degenerate (T/T_F~0.3) 6Li with 1.2*10^4 atoms. Quasipure Bose-Einstein condensates of up to 3*10^4 174Yb atoms can be produced in single-species experiments. Our results mark a significant step toward studies of few and many-body physics with mixtures of alkali and alkaline-earth-like atoms, and for the production of paramagnetic polar molecules in the quantum regime. Our methods also establish a convenient scheme for producing quantum degenerate ytterbium atoms in a 1064nm optical dipole trap.Comment: 4 pages, 3 figure

Labor Law - National Labor Relations Board - Effect of the NLRB\u27s Refusal to Take Jurisdiction

Appellant corporation was charged by the United Steelworkers of America with unfair labor practices in violation of sections 8(a)(1), (3) and (5) of the National Labor Relations Act. Although appellant\u27s business affected commerce within the meaning of the act, the acting regional director of the NLRB declined to issue a complaint because the company\u27s volume of business did not meet the Board\u27s revised minimum jurisdictional standards. The union then filed substantially the same charges with the Utah Labor Relations Board. The Utah Board\u27s determination that it had jurisdiction was affirmed by the Utah Supreme Court. On certiorari to the Supreme Court of the United States, held, reversed, two justices dissenting. The proviso to section 10(a) of the NLRA offers the exclusive means whereby states may assume jurisdiction over matters which Congress has entrusted to the NLRB. Guss v. Utah Labor Board, 353 U.S. I (1957)

Sympathetic cooling in an optically trapped mixture of alkali and spin-singlet atoms

We report on the realization of a stable mixture of ultracold lithium and ytterbium atoms confined in a far-off-resonance optical dipole trap. We observe sympathetic cooling of 6Li by 174Yb and extract the s-wave scattering length magnitude |a6Li-174Yb| = (13 \pm 3)a0 from the rate of inter-species thermalization. Using forced evaporative cooling of 174Yb, we achieve reduction of the 6Li temperature to below the Fermi temperature, purely through inter-species sympathetic cooling.Comment: 4 pages, 3 figure

Dynamics of Feshbach Molecules in an Ultracold Three-Component Mixture

We present investigations of the formation rate and collisional stability of lithium Feshbach molecules in an ultracold three-component mixture composed of two resonantly interacting fermionic 6-Li spin states and bosonic 174-Yb. We observe long molecule lifetimes (> 100 ms) even in the presence of a large ytterbium bath and extract reaction rate coefficients of the system. We find good collisional stability of the mixture in the unitary regime, opening new possibilities for studies and probes of strongly interacting quantum gases in contact with a bath species.Comment: 5 pages, 3 figure

Are you a caregiver infographic

After our 2018 Nursing-Interprofessional Salon that focused on older adults\u27 wellness, we formed the Are You a Caregiver Initiative. We developed an infographic to help individuals self-identify as a caregiver and to link them with available caregiver support resources. We plan to disseminate this infographic within the UMassMemorial system as well as surrounding environs. The infographic can be adapted for use in other communities as well

Reducing pup litter size alters early postnatal calcium homeostasis and programs adverse adult cardiovascular and bone health in male rats

The in utero and early postnatal environments play essential roles in offspring growth and development. Standardizing or reducing pup litter size can independently compromise long-term health likely due to altered milk quality, thus limiting translational potential. This study investigated the effect reducing litter size has on milk quality and offspring outcomes. On gestation day 18, dams underwent sham or bilateral uterine vessel ligation surgery to generate dams with normal (Control) and altered (Restricted) milk quality/composition. At birth, pups were cross-fostered onto separate dams with either an unadjusted or reduced litter size. Plasma parathyroid hormone-related protein was increased in Reduced litter pups, whereas ionic calcium and total body calcium were decreased. These data suggest Reduced litter pups have dysregulated calcium homeostasis in early postnatal life, which may impair bone mineralization decreasing adult bone bending strength. Dams suckling Reduced litter pups had increased milk long-chain monounsaturated fatty acid and omega-3 docosahexaenoic acid. Reduced litter pups suckled by Normal milk quality/composition dams had increased milk omega-6 linoleic and arachidonic acids. Reduced litter male adult offspring had elevated blood pressure. This study highlights care must be taken when interpreting data from research that alters litter size as it may mask subtle cardiometabolic health effects.Jessica F. Briffa, Rachael O’Dowd, Tania Romano, Beverly S. Muhlhausler, Karen M. Moritz and Mary E. Wlode

The Kinematics of Quasar Broad Emission Line Regions Using a Disk-Wind Model

The structure and kinematics of the broad line region in quasars are still unknown. One popular model is the disk-wind model that offers a geometric unification of a quasar based on the viewing angle. We construct a simple kinematical disk-wind model with a narrow outflowing wind angle. The model is combined with radiative transfer in the Sobolev, or high velocity, limit. We examine how angle of viewing affects the observed characteristics of the emission line. The line profiles were found to exhibit distinct properties depending on the orientation, wind opening angle, and region of the wind where the emission arises. At low inclination angle (close to face-on), we find that the shape of the emission line is asymmetric, narrow, and significantly blueshifted. As the inclination angle increases (close to edge-on), the line profile becomes more symmetric, broader, and less blueshifted. Additionally, lines that arise close to the base of the disk wind, near the accretion disk, tend to be broad and symmetric. Single-peaked line profiles are recovered for the intermediate and equatorial wind. The model is also able to reproduce a faster response in either the red or blue sides of the line profile, consistent with reverberation mapping studies.NFB thanks the STFC for support under Ernest Rutherford Grant ST/M003914/1