Reflections on a Measurement of the Gravitational Constant Using a Beam Balance and 13 Tons of Mercury

In 2006, a final result of a measurement of the gravitational constant $G$ performed by researchers at the University of Z\"urich was published. A value of G=6.674\,252(122)\times 10^{-11}\,\mbox{m}^3\,\mbox{kg}^{-1}\,\mbox{s}^{-2} was obtained after an experimental effort that lasted over one decade. Here, we briefly summarize the measurement and discuss the strengths and weaknesses of this approach.Comment: 13 pages, 5 figures accepted for publication in Phil. Trans. R. Soc.

Large-scale Monte Carlo simulations of the three-dimensional XY spin glass

We study the XY spin glass by large-scale Monte Carlo simulations for sizes up to 24^3, down to temperatures below the transition temperature found in earlier work. The data for the larger sizes show more marginal behavior than that for the smaller sizes indicating that the lower critical dimension is close to, and possibly equal to three. We find that the spins and chiralities behave in a very similar manner. We also address the optimal ratio of "over-relaxation" to "Metropolis" sweeps in the simulation.Comment: 6 pages, 6 postscript figures. Replaced by published versio

Mesothelial cells regulate immune responses in health and disease: Role for immunotherapy in malignant mesothelioma

Highlights: Mesothelial and immune cell interactions play a crucial role in tissue homeostasis in the serosal cavities such as the pleura. Mesothelin is viewed as an attractive target for solid tumors, including malignant mesothelioma. Checkpoint inhibitor therapy has shown variable efficacy against malignant mesothelioma. CAR T cell therapies are being evaluated for malignant mesothelioma. Treatment of malignant mesothelioma will require multimodality approaches with immunotherapy central to future therapeutic approaches. The mesothelium when first described was thought to function purely as a non-adhesive surface to facilitate intracoelomic movement of organs. However, the mesothelium is now recognized as a dynamic cellular membrane with many important functions that maintain serosal integrity and homeostasis. For example, mesothelial cells interact with and help regulate the body’s inflammatory and immune system following infection, injury, or malignancy. With recent advances in our understanding of checkpoint molecules and the advent of novel immunotherapy approaches, there has been an increase in the number of studies examining mesothelial and immune cell interaction, in particular the role of these interactions in malignant mesothelioma. This review will highlight some of the recent advances in our understanding of how mesothelial cells help regulate serosal immunity and how in a malignant environment, the immune system is hijacked to stimulate tumor growth. Ways to treat mesothelioma using immunotherapy approaches will also be discussed

A Measurement of Newton's Gravitational Constant

A precision measurement of the gravitational constant $G$ has been made using a beam balance. Special attention has been given to determining the calibration, the effect of a possible nonlinearity of the balance and the zero-point variation of the balance. The equipment, the measurements and the analysis are described in detail. The value obtained for G is 6.674252(109)(54) 10^{-11} m3 kg-1 s-2. The relative statistical and systematic uncertainties of this result are 16.3 10^{-6} and 8.1 10^{-6}, respectively.Comment: 26 pages, 20 figures, Accepted for publication by Phys. Rev.

Magic-Angle Semimetals with Chiral Symmetry

We construct and solve a two-dimensional, chirally symmetric model of Dirac cones subjected to a quasiperiodic modulation. In real space, this is realized with a quasiperiodic hopping term. This hopping model, as we show, at the Dirac node energy has a rich phase diagram with a semimetal-to-metal phase transition at intermediate amplitude of the quasiperiodic modulation, and a transition to a phase with a diverging density of states and sub-diffusive transport when the quasiperiodic hopping is strongest. We further demonstrate that the semimetal-to-metal phase transition can be characterized by the multifractal structure of eigenstates in momentum space and can be considered as a unique "unfreezing" transition. This unfreezing transition in momentum space generates flat bands with a dramatically renormalized bandwidth in the metallic phase similar to the phenomena of the band structure of twisted bilayer graphene at the magic angle. We characterize the nature of this transition numerically as well as analytically in terms of the formation of a band of topological zero modes. For pure quasiperiodic hopping, we provide strong numerical evidence that the low-energy density of states develops a divergence and the eigenstates exhibit Chalker (quantum-critical) scaling despite the model not being random. At particular commensurate limits the model realizes higher-order topological insulating phases. We discuss how these systems can be realized in experiments on ultracold atoms and metamaterials.Comment: 20+4 pages, 24 figures, published versio

Regulation of lamellipodial persistence, adhesion turnover, and motility in macrophages by focal adhesion kinase

Macrophages are a key component of the innate immune system. In this study, we investigate how focal adhesion kinase (FAK) and the related kinase Pyk2 integrate adhesion signaling and growth factor receptor signaling to regulate diverse macrophage functions. Primary bone marrow macrophages isolated from mice in which FAK is conditionally deleted from cells of the myeloid lineage exhibited elevated protrusive activity, altered adhesion dynamics, impaired chemotaxis, elevated basal Rac1 activity, and a marked inability to form stable lamellipodia necessary for directional locomotion. The contribution of FAK to macrophage function in vitro was substantiated in vivo by the finding that recruitment of monocytes to sites of inflammation was impaired in the absence of FAK. Decreased Pyk2 expression in primary macrophages also resulted in a diminution of invasive capacity. However, the combined loss of FAK and Pyk2 had no greater effect than the loss of either molecule alone, indicating that both kinases function within the same pathway to promote invasion

PERANCANGAN SITUS WEB E-COMMERCE LUGOET BAMBU DAN PEMASARANNYA MENUJU GO INTERNATIONAL

Considerable efforts have been made in recent years to theoretically understand quantum phase transitions in Kondo lattice systems. A particular focus is on Kondo destruction, which leads to quantum criticality that goes beyond the Landau framework of order-parameter fl uctuations. This unconventional quantum criticality has provided an understanding of the unusual dynamical scaling observed experimentally. It also predicted a sudden jump of the Fermi surface and an extra (Kondo destruction) energy scale, both of which have been veri fi ed by systematic experiments. Considerations of Kondo destruction have in addition yielded a global phase diagram, which has motivated the current interest in heavy fermion materials with variable dimensionality or geometrical frustration. Here we summarize these developments, and discuss some of the ongoing work and open issues. We also consider the implications of these results for superconductivity. Finally, we address the effect of spin – orbit coupling on the global phase diagram, suggest that SmB 6 under pressure may display unconventional superconductivity in the transition regime between a Kondo insulator phase and an antiferroamgnetic metal phase, and argue that the interfaces of heavy-fermion heterostructures will provide a fertile setting to explore topological properties of both Kondo insulators and heavy- fermion superconductors