Evidence for a continuum limit in causal set dynamics

We find evidence for a continuum limit of a particular causal set dynamics which depends on only a single ``coupling constant'' $p$ and is easy to simulate on a computer. The model in question is a stochastic process that can also be interpreted as 1-dimensional directed percolation, or in terms of random graphs.Comment: 24 pages, 19 figures, LaTeX, adjusted terminolog

Clearance of the mutant androgen receptor in motoneuronal models of spinal and bulbar muscular atrophy.

Spinal and bulbar muscular atrophy (SBMA) is an X-linked motoneuron disease caused by an abnormal expansion of a tandem CAG repeat in exon 1 of the androgen receptor (AR) gene that results in an abnormally long polyglutamine tract (polyQ) in the AR protein. As a result, the mutant AR (ARpolyQ) misfolds, forming cytoplasmic and nuclear aggregates in the affected neurons. Neurotoxicity only appears to be associated with the formation of nuclear aggregates. Thus, improved ARpolyQ cytoplasmic clearance, which indirectly decreases ARpolyQ nuclear accumulation, has beneficial effects on affected motoneurons. In addition, increased ARpolyQ clearance contributes to maintenance of motoneuron proteostasis and viability, preventing the blockage of the proteasome and autophagy pathways that might play a role in the neuropathy in SBMA. The expression of heat shock protein B8 (HspB8), a member of the small heat shock protein family, is highly induced in surviving motoneurons of patients affected by motoneuron diseases, where it seems to participate in the stress response aimed at cell protection. We report here that HspB8 facilitates the autophagic removal of misfolded aggregating species of ARpolyQ. In addition, though HspB8 does not influence p62 and LC3 (two key autophagic molecules) expression, it does prevent p62 bodies formation, and restores the normal autophagic flux in these cells. Interestingly, trehalose, a well-known autophagy stimulator, induces HspB8 expression, suggesting that HspB8 might act as one of the molecular mediators of the proautophagic activity of trehalose. Collectively, these data support the hypothesis that treatments aimed at restoring a normal autophagic flux that result in the more efficient clearance of mutant ARpolyQ might produce beneficial effects in SBMA patients

Leptospirosis followed by Kawasaki-like disease: case report from an adult Swiss patient and review of the literature

Kawasaki disease (KD) is a vasculitis that mostly occurs in children, but rare cases in adults have been reported. We describe the case of a 43-year-old Swiss male who developed symptoms compatible with KD 7 weeks after leptospirosis, which was presumably acquired after swimming in a creek in the Swiss Alps. We performed a literature review and identified 10 other cases (all in children), in which Kawasaki-like disease was diagnosed in the context of leptospirosis. Outcome was favourable in most cases, including our patient. This exceptional case demonstrates both the possibility of autochthonous cases of leptospirosis in Switzerland as well as a possible association of leptospirosis with Kawasaki-like disease

Stochastic Lagrangian Particle Approach to Fractal Navier-Stokes Equations

In this article we study the fractal Navier-Stokes equations by using stochastic Lagrangian particle path approach in Constantin and Iyer \cite{Co-Iy}. More precisely, a stochastic representation for the fractal Navier-Stokes equations is given in terms of stochastic differential equations driven by L\'evy processes. Basing on this representation, a self-contained proof for the existence of local unique solution for the fractal Navier-Stokes equation with initial data in \mW^{1,p} is provided, and in the case of two dimensions or large viscosity, the existence of global solution is also obtained. In order to obtain the global existence in any dimensions for large viscosity, the gradient estimates for L\'evy processes with time dependent and discontinuous drifts is proved.Comment: 19 page

Neuroimaging in cannabis use: a systematic review of the literature

Background We conducted a systematic review to assess the evidence for specific effects of cannabis on brain structure and function. The review focuses on the cognitive changes associated with acute and chronic use of the drug. Method We reviewed literature reporting neuroimaging studies of chronic or acute cannabis use published up until January 2009. The search was conducted using Medline, EMBASE, LILACS and PsycLIT indexing services using the following key words: cannabis, marijuana, delta-9-tetrahydrocannabinol, THC, cannabidiol, CBD, neuroimaging, brain imaging, computerized tomography, CT, magnetic resonance, MRI, single photon emission tomography, SPECT, functional magnetic resonance, fMRI, positron emission tomography, PET, diffusion tensor MRI, DTI-MRI, MRS and spectroscopy. Results Sixty-six studies were identified, of which 41 met the inclusion criteria. Thirty-three were functional (SPECT/PET/fMRI) and eight structural (volumetric/DTI) imaging studies. The high degree of heterogeneity across studies precluded a meta-analysis. The functional studies suggest that resting global and prefrontal blood flow are lower in cannabis users than in controls. The results from the activation studies using a cognitive task are inconsistent because of the heterogeneity of the methods used. Studies of acute administration of THC or marijuana report increased resting activity and activation of the frontal and anterior cingulate cortex during cognitive tasks. Only three of the structural imaging studies found differences between users and controls. Conclusions Functional neuroimaging studies suggest a modulation of global and prefrontal metabolism both during the resting state and after the administration of THC/marijuana cigarettes. Minimal evidence of major effects of cannabis on brain structure has been reporte

Towards InSAR Everywhere, All the Time, With Sentinel-1

Sentinel-1A was launched in April 2014, and has been collecting data routinely over more than one year. Sentinel-1B is set for launch on 22 April 2016. The Sentinel-1 constellation has several advantages over previous radar missions for InSAR applications: (1) Data are being acquired systematically for tectonic and volcanic areas, (2) Images cover a wide footprint, 250 km from near to far range in Interferometric Wide Swath (TOPS) mode, (3) Small perpendicular and temporal baselines greatly improve interferometric coherence at C-band, (4) Data are freely available to all users, (5) The mission is planned to be operational for 20 years, with 1C and 1D planned for future launches. These features enable us to map geological processes occurring in any place at anytime using InSAR.We will review progress within COMET towards our ultimate goal of building a fully-automated processing system that provides deformation results and derived products to the wide InSAR and Geophysics communities. In addition to high-resolution-ECMWF-based atmospheric correction model, we will show results of a systematic analysis of interferometric coherence in tectonic and volcanic areas, and discuss the future goals and timeline for the COMET InSAR automated processing system

Pretransplantation 18F-Fluorodeoxyglucose positron emission tomography scan predicts outcome in patients with recurrent Hodgkin lymphoma or aggressive non-hodgkin lymphoma undergoing reduced-intensity conditioning follone by allogeneic stem cell transplantation

Background: The use of positron emission tomography (PET) scanning in Hodgkin lymphoma (HL) and aggressive non-Hodgkin lymphoma (HG-NHL) has recognized prognostic value in patients who are receiving chemotherapy or undergoing autologous stem cell transplantation (SCT). In contrast, the role of PET before reduced-intensity conditioning (RIC) and followed by allogeneic SCT has not been investigated to date. Methods: PET was used to assess 80 patients who had chemosensitive disease (34 patients with HG-NHL and 46 patients with HL) before they underwent allogeneic SCT: 42 patients had negative PET studies, and 38 patients had positive PET studies. Patients underwent allograft from matched related siblings (n = 41) or alternative donors (n = 39). Results: At the time of the last follow-up, 48 patients were alive (60%), and 32 had died. The 3-year cumulative incidence of nonrecurrence mortality and disease recurrence was 17% and 40%, respectively. The cumulative incidence of disease recurrence was significantly lower in the PET-negative patients (25% vs 56%; P =.007), but there was no significant difference between the patients with or without chronic graft-versus-host disease (P =.400). The patients who had negative PET studies before undergoing allogenic SCT also had significantly better outcomes in terms of 3-year overall survival (76% vs 33%; P =.001) and 3-year progression-free survival (73% vs 31%; P =.001). On multivariate analysis, overall survival was influenced by PET status (hazard ratio [HR], 3.35), performance status (HR, 5.15), and type of donor (HR, 6.26 for haploidentical vs sibling; HR, 1.94 for matched unrelated donor vs sibling). Conclusions: The current results indicated that PET scanning appears to be an accurate tool for assessing prognosis in patients who are eligible for RIC allografting