Report on a collecting trip of the British Myriapod Group to Hungary in 1994

During a collecting trip participated jointly by the members of the British Myriapod Group and by Hungarian experts in 1994, 34 species of millipedes, 14 of centipedes, 8 of woodlice and 73 of spiders were recorded from Hungary. Two records of the millipede species Boreoiulus tenuis (Bigler, 1913) and Styrioiulus styricus (Verhoeff, 1896) were new to the fauna of Hungary

Evidence for a dynamical ground state in the frustrated pyrohafnate Tb2Hf2O7

We report the physical properties of Tb2Hf2O7 based on ac magnetic susceptibility \chi_ac(T), dc magnetic susceptibility \chi(T), isothermal magnetization M(H), and heat capacity C_p(T) measurements combined with muon spin relaxation (\muSR) and neutron powder diffraction measurements. No evidence for long-range magnetic order is found down to 0.1 K. However, \chi_ac(T) data present a frequency-dependent broad peak (near 0.9 K at 16 Hz) indicating slow spin dynamics. The slow spin dynamics is further evidenced from the \muSR data (characterized by a stretched exponential behavior) which show persistent spin fluctuations down to 0.3 K. The neutron powder diffraction data collected at 0.1 K show a broad peak of magnetic origin (diffuse scattering) but no magnetic Bragg peaks. The analysis of the diffuse scattering data reveals a dominant antiferromagnetic interaction in agreement with the negative Weiss temperature. The absence of long-range magnetic order and the presence of slow spin dynamics and persistent spin fluctuations together reflect a dynamical ground state in Tb2Hf2O7.Comment: 11 pages and 8 figure

Homogenization of Variational Inequalities for the p-Laplace Operator in Perforated Media Along Manifolds

We address homogenization problems of variational inequalities for the p-Laplace operator in a domain of Rn (n ? 3, p ? [2, n)) periodically perforated by balls of radius O(??) where ? > 1 and ? is the size of the period. The perforations are distributed along a (n ? 1)-dimensional manifold ? , and we impose constraints for solutions and their fluxes (associated with the p-Laplacian) on the boundary of the perforations. These constraints imply that the solution is positive and that the flux is bounded from above by a negative, nonlinear monotonic function of the solution multiplied by a parameter ? ?? , ? ? R and ? is a small parameter that we shall make to go to zero. We analyze different relations between the parameters p, n, ?, ? and ?, and obtain homogenized problems which are completely new in the literature even for the case p = 2.This work has been partially supported by the Spanish grant MINECO:MTM2013-44883-P

Human GBP1 is a microbe-specific gatekeeper of macrophage apoptosis and pyroptosis

The guanylate binding protein (GBP) family of interferon-inducible GTPases promotes antimicrobial immunity and cell death. During bacterial infection, multiple mouse Gbps, human GBP2, and GBP5 support the activation of caspase-1-containing inflammasome complexes or caspase-4 which trigger pyroptosis. Whether GBPs regulate other forms of cell death is not known. The apicomplexan parasite Toxoplasma gondii causes macrophage death through unidentified mechanisms. Here we report that Toxoplasma-induced death of human macrophages requires GBP1 and its ability to target Toxoplasma parasitophorous vacuoles through its GTPase activity and prenylation. Mechanistically, GBP1 promoted Toxoplasma detection by AIM2, which induced GSDMD-independent, ASC-, and caspase-8-dependent apoptosis. Identical molecular determinants targeted GBP1 to Salmonella-containing vacuoles. GBP1 facilitated caspase-4 recruitment to Salmonella leading to its enhanced activation and pyroptosis. Notably, GBP1 could be bypassed by the delivery of Toxoplasma DNA or bacterial LPS into the cytosol, pointing to its role in liberating microbial molecules. GBP1 thus acts as a gatekeeper of cell death pathways, which respond specifically to infecting microbes. Our findings expand the immune roles of human GBPs in regulating not only pyroptosis, but also apoptosis

Woodlice (Isopoda: Oniscidea) and the centipede Scutigera coleoptrata (Chilopoda) collected from Hungary by the British Myriapod Group in 1994:

Twenty-seven species of woodlice are recorded from Hungary in 1994 during a joint collecting trip undertaken by the British Myriapod Group and Hungarian experts. Five species, Armadillidium vulgare (LATREILLE, 1804), Protracheoniscus politus (C. KOCH, 1841), Trachelipus rathkii (BRANDT, 1833), Platyarthrus hoffmannseggii BRANDT, 1833 and Trachelipus nodulosus (C.KOCH, 1838), were widely recorded and accounted for 48% of the 1,200 specimens collected. The first Hungarian record of Trichoniscus provisorius RACOVITZA, 1908 is given. Records of the apparently rare species, including Trichoniscus steinboecki VERHOEFF, 1931, Hyloniscus vividus (C. KOCH, 1841), Haplophthalmus montivagus VERHOEFF, 1941 and Lepidoniscus minutus (C. KOCH, 1838) are presented for semi-natural habitats. It is suggested that some of these species, particularly H. montivagus, may have been over looked and consequently may be under recorded. Other apparently rare species, including Androniscus roseus (C. KOCH, 1838), Oniscus asellus Linnaeus, 1758, Porcellio spinicornis SAY, 1818 and Armadillidium nasatum BUDDE-LUND, 1885 are recorded from synanthropic sites. The potential value of synanthropic habitats for Oniscidea is highlighted. A record for the centipede, Scutigera coleoptrata LINNAEUS, 1758 is given

Interaction of Chemistry, Turbulence, and Shock Waves in Hypervelocity Flow

Significant progress was made in the third year of an interdisciplinary experimental, numerical and theoretical program to extend the state of knowledge and understanding of the effects of chemical reactions in hypervelocity flows. The program addressed the key problems in aerothermochemistry that arise from.the interaction between the three strongly nonlinear effects: Compressibility; vorticity; and chemistry. Important new results included: • New data on transition in hypervelocity carbon dioxide flows • New method of free-piston shock tunnel operation for lower enthalpy • Accurate new method for computation of self-similar flows • New experimental data on flap-induced separation at high enthalpy • Insight into mechanisms active in reacting shear layers from comparison of experiment and computation • Extensive new data from Rayleigh scattering diagnostics of supersonic shear layer • Comparison of new experiments and computation of hypervelocity double-wedge flow yielded important differences • Further first-principles computations of electron collision cross-sections of CO, N_2 and NO • Good agreement between EFMO computation and experiment of flow over a cone at high incidence • Extension of LITA diagnostics to high temperature

Gut microbiota and colonization resistance against bacterial enteric infection

The gut microbiome is critical in providing resistance against colonization by exogenous microorganisms. The mechanisms via which the gut microbiota provide colonization resistance (CR) have not been fully elucidated, but they include secretion of antimicrobial products, nutrient competition, support of gut barrier integrity, and bacteriophage deployment. However, bacterial enteric infections are an important cause of disease globally, indicating that microbiota-mediated CR can be disturbed and become ineffective. Changes in microbiota composition, and potential subsequent disruption of CR, can be caused by various drugs, such as antibiotics, proton pump inhibitors, antidiabetics, and antipsychotics, thereby providing opportunities for exogenous pathogens to colonize the gut and ultimately cause infection. In addition, the most prevalent bacterial enteropathogens, including Clostridioides diflicile, Salmonella enterica serovar Typhimurium, enterohemorrhagic Escherichia coli, Shigella flexneri, Campylobacter jejuni, Vibrio cholerae, Yersinia enterocolitica, and Listeria monocytogenes, can employ a wide array of mechanisms to overcome colonization resistance. This review aims to summarize current knowledge on how the gut microbiota can mediate colonization resistance against bacterial enteric infection and on how bacterial enteropathogens can overcome this resistance.Molecular basis of bacterial pathogenesis, virulence factors and antibiotic resistanc

The Frequency Dependent Conductivity of Electron Glasses

Results of DC and frequency dependent conductivity in the quantum limit, i.e. hw > kT, for a broad range of dopant concentrations in nominally uncompensated, crystalline phosphorous doped silicon and amorphous niobium-silicon alloys are reported. These materials fall under the general category of disordered insulating systems, which are referred to as electron glasses. Using microwave resonant cavities and quasi-optical millimeter wave spectroscopy we are able to study the frequency dependent response on the insulating side of the metal-insulator transition. We identify a quantum critical regime, a Fermi glass regime and a Coulomb glass regime. Our phenomenological results lead to a phase diagram description, or taxonomy, of the electrodynamic response of electron glass systems

Relativistic MHD with Adaptive Mesh Refinement

This paper presents a new computer code to solve the general relativistic magnetohydrodynamics (GRMHD) equations using distributed parallel adaptive mesh refinement (AMR). The fluid equations are solved using a finite difference Convex ENO method (CENO) in 3+1 dimensions, and the AMR is Berger-Oliger. Hyperbolic divergence cleaning is used to control the $\nabla\cdot {\bf B}=0$ constraint. We present results from three flat space tests, and examine the accretion of a fluid onto a Schwarzschild black hole, reproducing the Michel solution. The AMR simulations substantially improve performance while reproducing the resolution equivalent unigrid simulation results. Finally, we discuss strong scaling results for parallel unigrid and AMR runs.Comment: 24 pages, 14 figures, 3 table

Passing to the Limit in a Wasserstein Gradient Flow: From Diffusion to Reaction

We study a singular-limit problem arising in the modelling of chemical reactions. At finite {\epsilon} > 0, the system is described by a Fokker-Planck convection-diffusion equation with a double-well convection potential. This potential is scaled by 1/{\epsilon}, and in the limit {\epsilon} -> 0, the solution concentrates onto the two wells, resulting into a limiting system that is a pair of ordinary differential equations for the density at the two wells. This convergence has been proved in Peletier, Savar\'e, and Veneroni, SIAM Journal on Mathematical Analysis, 42(4):1805-1825, 2010, using the linear structure of the equation. In this paper we re-prove the result by using solely the Wasserstein gradient-flow structure of the system. In particular we make no use of the linearity, nor of the fact that it is a second-order system. The first key step in this approach is a reformulation of the equation as the minimization of an action functional that captures the property of being a curve of maximal slope in an integrated form. The second important step is a rescaling of space. Using only the Wasserstein gradient-flow structure, we prove that the sequence of rescaled solutions is pre-compact in an appropriate topology. We then prove a Gamma-convergence result for the functional in this topology, and we identify the limiting functional and the differential equation that it represents. A consequence of these results is that solutions of the {\epsilon}-problem converge to a solution of the limiting problem.Comment: Added two sections, corrected minor typos, updated reference