A stochastic vortex structure method for interacting particles in turbulent shear flows

In a recent study, we have proposed a new synthetic turbulence method based on stochastic vortex structures (SVSs), and we have demonstrated that this method can accurately predict particle transport, collision, and agglomeration in homogeneous, isotropic turbulence in comparison to direct numerical simulation results. The current paper extends the SVS method to non-homogeneous, anisotropic turbulence. The key element of this extension is a new inversion procedure, by which the vortex initial orientation can be set so as to generate a prescribed Reynolds stress field. After validating this inversion procedure for simple problems, we apply the SVS method to the problem of interacting particle transport by a turbulent planar jet. Measures of the turbulent flow and of particle dispersion, clustering, and collision obtained by the new SVS simulations are shown to compare well with direct numerical simulation results. The influence of different numerical parameters, such as number of vortices and vortex lifetime, on the accuracy of the SVS predictions is also examined

Life-Cycle Impacts of Forest Resource Activities in the Pacific Northwest and Southeast United States

A more intensive management alternative was created for each region by reallocating acres to higher management intensity classes. Harvesting activities were segmented into five stages to allow development of all inputs and outputs: (1) felling, (2) processing (bucking, limbing, cutting to length), (3) secondary transportation (skidding and yarding), (4) loading, and (5) hauling to a process point. The costs and consumption rates of energy and materials for these activities drove the log outputs, emissions, and carbon pools. Logs are allocated to wood product facilities, the primary product of the analysis, or pulp and paper mills as a co-product from the forest. Non-merchantable slash is generally left on site and is disposed of through site preparation activities. Transportation-related activities and the required diesel fuel produce by far the largest contribution to emission outputs. However, fertilizer use contributes to much of the change in emissions as acreage shifts to higher intensity management alternatives

The Solar-System-Scale Disk Around AB Aurigae

The young star AB Aurigae is surrounded by a complex combination of gas-rich and dust dominated structures. The inner disk which has not been studied previously at sufficient resolution and imaging dynamic range seems to contain very little gas inside a radius of least 130 astronomical units (AU) from the star. Using adaptive-optics coronagraphy and polarimetry we have imaged the dust in an annulus between 43 and 302 AU from the star, a region never seen before. An azimuthal gap in an annulus of dust at a radius of 102 AU, along with a clearing at closer radii inside this annulus, suggests the formation of at least one small body at an orbital distance of about 100 AU. This structure seems consistent with crude models of mean motion resonances, or accumulation of material at two of the Lagrange points relative to the putative object and the star. We also report a low significance detection of a point source in this outer annulus of dust. This source may be an overdensity in the disk due to dust accreting onto an unseen companion. An alternate interpretation suggests that the object's mass is between 5 and 37 times the mass of Jupiter. The results have implications for circumstellar disk dynamics and planet formation.Comment: 11 pages, 5 figures, accepted for publication in Astrophysical Journal, V. 680, June 10, 200

Grief and Avoidant Death Attitudes Combine to Predict the Fading Affect Bias

The fading affect bias (FAB) occurs when unpleasant affect fades faster than pleasant affect. To detect mechanisms that influence the FAB in the context of death, we measured neuroticism, depression, anxiety, negative religious coping, death attitudes, and complicated grief as potential predictors of FAB for unpleasant/death and pleasant events at 2 points in time. The FAB was robust across older and newer events, which supported the mobilization-minimization hypothesis. Unexpectedly, complicated grief positively predicted FAB, and death avoidant attitudes moderated this relation, such that the Initial Event Affect by Grief interaction was only significant at the highest 3 quintiles of death avoidant attitudes. These results were likely due to moderate grief ratings, which were, along with avoidant death attitudes, related to healthy outcomes in past research. These results implicate complicated grief and death avoidant attitudes as resiliency mechanisms that are mobilized during bereavement to minimize its unpleasant effects

microRNA-219 Reduces Viral Load and Pathologic Changes in Theiler's Virus-Induced Demyelinating Disease

Analysis of microRNA (miR) expression in the central nervous system white matter of SJL mice infected with the BeAn strain of Theiler's murine encephalomyelitis virus (TMEV) revealed a significant reduction of miR-219, a critical regulator of myelin assembly and repair. Restoration of miR-219 expression by intranasal administration of a synthetic miR-219 mimic before disease onset ameliorates clinical disease, reduces neurogliosis, and partially recovers motor and sensorimotor function by negatively regulating proinflammatory cytokines and virus RNA replication. Moreover, RNA sequencing of host lesions showed that miR-219 significantly downregulated two genes essential for the biosynthetic cholesterol pathway, Cyp51 (lanosterol 14-α-demethylase) and Srebf1 (sterol regulatory element-binding protein-1), and reduced cholesterol biosynthesis in infected mice and rat CG-4 glial precursor cells in culture. The change in cholesterol biosynthesis had both anti-inflammatory and anti-viral effects. Because RNA viruses hijack endoplasmic reticulum double-layered membranes to provide a platform for RNA virus replication and are dependent on endogenous pools of cholesterol, miR-219 interference with cholesterol biosynthesis interfered virus RNA replication. These findings demonstrate that miR-219 inhibits TMEV-induced demyelinating disease through its anti-inflammatory and anti-viral properties. MicroRNAs (miRs) are small noncoding RNAs that regulate a myriad of biological processes by controlling gene expression. In the latest issue of Molecular Therapy, Moyano et al. show that intranasal delivery of miR-219 in a mouse model of viral demyelination reduces neurological burden and improves life quality through anti-inflammatory and anti-viral mechanisms.Fil: Moyano, Ana Lis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Instituto Universitario de Ciencias Biomédicas de Córdoba; Argentina. University of Illinois; Estados UnidosFil: Steplowski, Jeffrey. University of Illinois; Estados UnidosFil: Wang, Haibo. Cincinnati Children's Hospital Medical Center; Estados UnidosFil: Son, Kyung No. University of Illinois; Estados UnidosFil: Rapolti, Diana I.. University of Illinois; Estados UnidosFil: Marshall, Jeffrey. University of Illinois; Estados UnidosFil: Elackattu, Vince. University of Illinois; Estados UnidosFil: Marshall, Michael S.. University of Illinois; Estados UnidosFil: Hebert, Amy K.. University of Illinois; Estados UnidosFil: Reiter, Cory R.. University of Illinois; Estados UnidosFil: Ulloa, Viviana. University of Illinois; Estados UnidosFil: Pituch, Katarzyna C.. University of Illinois; Estados UnidosFil: Givogri, Maria I.. University of Illinois; Estados UnidosFil: Lu, Q. Richard. Cincinnati Children's Hospital Medical Center; Estados UnidosFil: Lipton, Howard L.. University of Illinois; Estados UnidosFil: Bongarzone, Ernesto R.. University of Illinois; Estados Unidos. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Biológica; Argentin

Gemini Planet Imager Observational Calibrations VI: Photometric and Spectroscopic Calibration for the Integral Field Spectrograph

The Gemini Planet Imager (GPI) is a new facility instrument for the Gemini Observatory designed to provide direct detection and characterization of planets and debris disks around stars in the solar neighborhood. In addition to its extreme adaptive optics and corona graphic systems which give access to high angular resolution and high-contrast imaging capabilities, GPI contains an integral field spectrograph providing low resolution spectroscopy across five bands between 0.95 and 2.5 $\mu$m. This paper describes the sequence of processing steps required for the spectro-photometric calibration of GPI science data, and the necessary calibration files. Based on calibration observations of the white dwarf HD 8049B we estimate that the systematic error in spectra extracted from GPI observations is less than 5%. The flux ratio of the occulted star and fiducial satellite spots within coronagraphic GPI observations, required to estimate the magnitude difference between a target and any resolved companions, was measured in the $H$-band to be $\Delta m = 9.23\pm0.06$ in laboratory measurements and $\Delta m = 9.39\pm 0.11$ using on-sky observations. Laboratory measurements for the $Y$, $J$, $K1$ and $K2$ filters are also presented. The total throughput of GPI, Gemini South and the atmosphere of the Earth was also measured in each photometric passband, with a typical throughput in $H$-band of 18% in the non-coronagraphic mode, with some variation observed over the six-month period for which observations were available. We also report ongoing development and improvement of the data cube extraction algorithm.Comment: 15 pages, 6 figures. Proceedings of the SPIE, 9147-30

α-Synuclein interacts directly but reversibly with psychosine: implications for α-synucleinopathies

Aggregation of α-synuclein, the hallmark of α-synucleinopathies such as Parkinson´s disease, occurs in various glycosphingolipidoses. Although α-synuclein aggregation correlates with deficiencies in the lysosomal degradation of glycosphingolipids (GSL), the mechanism(s) involved in this aggregation remains unclear. We previously described the aggregation of α-synuclein in Krabbe´s disease (KD), a neurodegenerative glycosphingolipidosis caused by lysosomal deficiency of galactosyl-ceramidase (GALC) and the accumulation of the GSL psychosine. Here, we used a multi-pronged approach including genetic, biophysical and biochemical techniques to determine the pathogenic contribution, reversibility, and molecular mechanism of aggregation of α-synuclein in KD. While genetic knock-out of α-synuclein reduces, but does not completely prevent, neurological signs in a mouse model of KD, genetic correction of GALC deficiency completely prevents α-synuclein aggregation. We show that psychosine forms hydrophilic clusters and binds the C-terminus of α-synuclein through its amino group and sugar moiety, suggesting that psychosine promotes an open/aggregation-prone conformation of α-synuclein. Dopamine and carbidopa reverse the structural changes of psychosine by mediating a closed/aggregation-resistant conformation of α-synuclein. Our results underscore the therapeutic potential of lysosomal correction and small molecules to reduce neuronal burden in α-synucleinopathies, and provide a mechanistic understanding of α-synuclein aggregation in glycosphingolipidoses.Fil: Abdelkarim, Hazem. University of Illinois; Estados UnidosFil: Marshall, Michael S.. University of Illinois; Estados UnidosFil: Scesa, Giuseppe. University of Illinois; Estados UnidosFil: Smith, Rachael A.. University of Illinois; Estados UnidosFil: Rue, Emily. University of Illinois; Estados UnidosFil: Marshall, Jeffrey. University of Illinois; Estados UnidosFil: Elackattu, Vince. University Of Illinois Chicago; Estados UnidosFil: Stoskute, Monika. University Of Illinois Chicago; Estados UnidosFil: Issa, Yazan. University Of Illinois Chicago; Estados UnidosFil: Santos, Marta. University Of Illinois Chicago; Estados UnidosFil: Nguyen, Duc. University Of Illinois Chicago; Estados UnidosFil: Hauck, Zane. University Of Illinois Chicago; Estados UnidosFil: Van Breemen, Richard B.. University Of Illinois Chicago; Estados UnidosFil: Celej, Maria Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Química Biológica de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Centro de Investigaciones en Química Biológica de Córdoba; ArgentinaFil: Gaponenko, Vadim. University Of Illinois Chicago; Estados UnidosFil: Bongarzone, Ernesto R.. University Of Illinois Chicago; Estados Unido

Control of an outbreak of carbapenem-resistant Acinetobacter baumannii in Australia after introduction of environmental cleaning with a commercial oxidizing disinfectant

In the midst of an outbreak, carbapenem-resistant Acinetobacter baumannii was grown from samples of multiple environmental sites in an intensive care unit. A commercial oxidizing disinfectant (potassium peroxomonosulphate 50%, sodium alkyl benzene sulphonate 15%, and sulphamic acid 5%) was introduced throughout the intensive care unit, and its use coincided with cessation of the outbreak