Parabolic groups acting on one-dimensional compact spaces

Given a class of compact spaces, we ask which groups can be maximal parabolic subgroups of a relatively hyperbolic group whose boundary is in the class. We investigate the class of 1-dimensional connected boundaries. We get that any non-torsion infinite f.g. group is a maximal parabolic subgroup of some relatively hyperbolic group with connected one-dimensional boundary without global cut point. For boundaries homeomorphic to a Sierpinski carpet or a 2-sphere, the only maximal parabolic subgroups allowed are virtual surface groups (hyperbolic, or virtually $\mathbb{Z} + \mathbb{Z}$).Comment: 10 pages. Added a precision on local connectedness for Lemma 2.3, thanks to B. Bowditc

Metatarsophalangeal joint pain in psoriatic arthritis: a cross-sectional study

Methods. Thirty-four consecutive patients with PsA (mean age 45.3 years, 65% female, mean disease duration 9.9 years) and 22 control participants (mean age 37.9 years, 64% female) underwent clinical and US examination to determine the presence of pain, swelling, synovitis, erosions, effusions and submetatarsal bursae at the MTP joints. Mean barefoot peak plantar pressures were determined at each MTP joint. Levels of pain, US-determined pathology and peak pressures were compared between groups. Binary logistic regression was used to identify demographic, clinical examination-derived, US-derived and plantar pressure predictors of pain at the MTP joints in the PsA group. Results. The presence of pain, deformity, synovitis, erosions (P < 0.001) and submetatarsal bursae and peak plantar pressure at MTP 3 (P < 0.05) were significantly higher in the PsA group. MTP joint pain in PsA was independently predicted by high BMI, female gender and the presence of joint subluxation, synovitis and erosion. Conclusion. These results suggest local inflammatory and structural factors, together with systemic factors (gender, BMI), are predominantly responsible for painful MTP joints in PsA, with no clear role for plantar pressure characteristics

Optical shield: measuring viscosity of turbid fluids using optical tweezers

The viscosity of a fluid can be measured by tracking the motion of a suspended micron-sized particle trapped by optical tweezers. However, when the particle density is high, additional particles entering the trap compromise the tracking procedure and degrade the accuracy of the measurement. In this work we introduce an additional Laguerre–Gaussian, i.e. annular, beam surrounding the trap, acting as an optical shield to exclude contaminating particles

Fiscal policies and the prices of labor: a comparison of the U.K. and U.S.

This paper measures the 2007-13 evolution of employment tax rates in the U.K. and the U.S. The U.S. changes are greater, in the direction of taxing a greater fraction of the value created by employment, and primarily achieved with new implicit tax rates. Even though both countries implemented a temporary "fiscal stimulus," their tax rate dynamics were different: the U.S. stimulus increased rates, whereas the U.K. stimulus reduced them. The U.K. later increased the tax on employment during its "austerity" period. Tax rate measurements are a first ingredient for cross-country comparisons of labor markets during and after the financial crisis

Trust, Familiarity, Optimism, and Pleasure: Australian Gay Men Accounting for Inconsistent HIV Prevention Practices in the PrEP Era

Despite an increase in the range of effective HIV risk reduction strategies that are available, some gay and bisexual men (GBM) do not use any of them consistently. Understanding why GBM do not always use a protective strategy may help develop more effective responses. Semi-structured interviews with 24 sexually active GBM in Sydney, Australia were conducted and analyzed using thematic analysis. The main characteristics of encounters featuring little or no use of HIV risk reduction strategies were familiarity and trust with partners, pleasure and intoxication, expectations that partners were using HIV pre-exposure prophylaxis or treatment as prevention, and in some cases feelings of inevitability about acquiring HIV. An increase in pleasure and a reduction in anxiety about sex were noted by some GBM who had commenced PrEP. Encouraging GBM to adopt a strategy such as PrEP and to use it consistently may be easier by emphasizing benefits to mental health and the quality of sex and intimacy it can offer. However, even with the increased availability of effective biomedical HIV risk reduction strategies, not all GBM are able to consistently manage HIV risk and some continue to hold optimistic and potentially inaccurate beliefs about sexual partners that may increase HIV risk

Estimates of economic and environmental damages from tipping points cannot be reconciled with the scientific literature

Peer reviewe