Superadiabatic forces in brownian many-body dynamics

Theoretical approaches to nonequilibrium many-body dynamics generally rest upon an adiabatic assumption, whereby the true dynamics is represented as a sequence of equilibrium states. Going beyond this simple approximation is a notoriously difficult problem. For the case of classical Brownian many-body dynamics, we present a simulation method that allows us to isolate and precisely evaluate superadiabatic correlations and the resulting forces. Application of the method to a system of one-dimensional hard particles reveals the importance for the dynamics, as well as the complexity, of these nontrivial out-of-equilibrium contributions. Our findings help clarify the status of dynamical density functional theory and provide a rational basis for the development of improved theories

Particle conservation in dynamical density functional theory

We present the exact adiabatic theory for the dynamics of the inhomogeneous density distribution of a classical fluid. Erroneous particle number fluctuations of dynamical density functional theory are absent, both for canonical and grand canonical initial conditions. We obtain the canonical free energy functional, which yields the adiabatic interparticle forces of overdamped Brownian motion. Using an exact and one of the most advanced approximate hard core free energy functionals, we obtain excellent agreement with simulations. The theory applies to finite systems in and out of equilibrium

Dust Temperatures in the Infrared Space Observatory Atlas of Bright Spiral Galaxies

We examine far-infrared and submillimeter spectral energy distributions for galaxies in the Infrared Space Observatory Atlas of Bright Spiral Galaxies. For the 71 galaxies where we had complete 60-180 micron data, we fit blackbodies with lambda^-1 emissivities and average temperatures of 31 K or lambda^-2 emissivities and average temperatures of 22 K. Except for high temperatures determined in some early-type galaxies, the temperatures show no dependence on any galaxy characteristic. For the 60-850 micron range in eight galaxies, we fit blackbodies with lambda^-1, lambda-2, and lambda^-beta (with beta variable) emissivities to the data. The best results were with the lambda^-beta emissivities, where the temperatures were ~30 K and the emissivity coefficient beta ranged from 0.9 to 1.9. These results produced gas to dust ratios that ranged from 150 to 580, which were consistent with the ratio for the Milky Way and which exhibited relatively little dispersion compared to fits with fixed emissivities.Comment: AJ, 2003, in pres

Quantitative metabolomics analysis of amino acid metabolism in recombinant Pichia pastoris under different oxygen availability conditions

Background: Environmental and intrinsic stress factors can result in the global alteration of yeast physiology, as evidenced by several transcriptional studies. Hypoxia has been shown to have a beneficial effect on the expression of recombinant proteins in Pichia pastoris growing on glucose. Furthermore, transcriptional profiling analyses revealed that oxygen availability was strongly affecting ergosterol biosynthesis, central carbon metabolism and stress responses, in particular the unfolded protein response. To contribute to the better understanding of the effect and interplay of oxygen availability and foreign protein secretion on central metabolism, a first quantitative metabolomic analysis of free amino acids pools in a recombinant P. pastoris strain growing under different oxygen availability conditions has been performed. Results: The values obtained indicate significant variations in the intracellular amino acid pools due to different oxygen availability conditions, showing an overall increase of their size under oxygen limitation. Notably, even while foreign protein productivities were relatively low (about 40-80 μg Fab/gDCW·h), recombinant protein production was found to have a limited but significant impact on the intracellular amino acid pools, which were generally decreased in the producing strain compared with the reference strain. However, observed changes in individual amino acids pools were not correlated with their corresponding relative abundance in the recombinant protein sequence, but to the overall cell protein amino acid compositional variations. Conclusions: Overall, the results obtained, combined with previous transcriptomic and proteomic analyses provide a systematic metabolic fingerprint of the oxygen availability impact on recombinant protein production in P. pastoris

The Walnuts and Healthy Aging study (WAHA): Protocol for a Nutritional Intervention Trial with Walnuts on Brain Aging

Introduction: An unwanted consequence of population aging is the growing number of elderly at risk of neurodegenerative disorders, including dementia and macular degeneration. As nutritional and behavioral changes can delay disease progression, we designed the Walnuts and Healthy Aging (WAHA) study, a two-center, randomized, 2-year clinical trial conducted in free-living, cognitively healthy elderly men and women. Our interest in exploring the role of walnuts in maintaining cognitive and retinal health is based on extensive evidence supporting their cardio-protective and vascular health effects, which are linked to bioactive components, such as n-3 fatty acids and polyphenols. Methods: The primary aim of WAHA is to examine the effects of ingesting walnuts daily for 2 years on cognitive function and retinal health, assessed with a battery of neuropsychological tests and optical coherence tomography, respectively. All participants followed their habitual diet, adding walnuts at 15% of energy (≈30-60 g/day) (walnut group) or abstaining from walnuts (control group). Secondary outcomes include changes in adiposity, blood pressure, and serum and urinary biomarkers in all participants and brain magnetic resonance imaging in a subset. Results: From May 2012 to May 2014, 708 participants (mean age 69 years, 68% women) were randomized. The study ended in May 2016 with a 90% retention rate. Discussion: The results of WAHA might provide high-level evidence of the benefit of regular walnut consumption in delaying the onset of age-related cognitive impairment and retinal pathology. The findings should translate into public health policy and sound recommendations to the general population

Squeezed by a Habitat Split: Warm Ocean Conditions and Old‐forest Loss Interact to Reduce Long‐term Occupancy of a Threatened Seabird

Theory predicts that species requiring multiple habitat types simultaneously should have heightened sensitivity to anthropogenic pressures, yet tests of this prediction are especially rare. We tested whether breeding site occupancy of the threatened marbled murrelet (Brachyramphus marmoratus) was driven by the synergistic effects of nesting habitat loss in forests, and changing ocean condi- tions. We paired 70,700 murrelet surveys at 19,837 sites across 20 years from the Oregon Coast Range with annual data on the extent of old forest and biophysical ocean conditions. Dynamic occupancy models indicated that local murrelet col- onization rates were strongly reduced during warm ocean conditions with low prey availability. Landscapes that contained more old forest and were closer to the ocean showed reduced rates of local extinction. Given predictions of accel- erated ocean warming and increased global timber demand, our results suggest murrelets may continue to be imperiled by deterioration of the two habitats upon which they depend

Comparison of Listeria monocytogenes Exoproteomes from biofilm and planktonic state:Lmo2504, a protein associated with biofilms

The food-borne pathogen Listeria monocytogenes is the causative agent of the severe human and animal disease listeriosis. The persistence of this bacterium in food processing environments is mainly attributed to its ability to form biofilms. The search for proteins associated with biofilm formation is an issue of great interest, with most studies targeting the whole bacterial proteome. Nevertheless, exoproteins constitute an important class of molecules participating in various physiological processes, such as cell signaling, pathogenesis, and matrix remodeling. The aim of this work was to quantify differences in protein abundance between exoproteomes from a biofilm and from the planktonic state. For this, two field strains previously evaluated to be good biofilm producers (3119 and J311) were used, and a procedure for the recovery of biofilm exoproteins was optimized. Proteins were resolved by two-dimensional difference gel electrophoresis and identified by electrospray ionization-tandem mass spectrometry. One of the proteins identified in higher abundance in the biofilm exoproteomes of both strains was the putative cell wall binding protein Lmo2504. A mutant strain with deletion of the gene for Lmo2504 was produced (3119Δlmo2504), and its biofilm-forming ability was compared to that of the wild type using the crystal violet and the ruthenium red assays as well as scanning electron microscopy. The results confirmed the involvement of Lmo2504 in biofilm formation, as strain 3119Δlmo2504 showed a significantly (P < 0.05) lower biofilm-forming ability than the wild type. The identification of additional exoproteins associated with biofilm formation may lead to new strategies for controlling this pathogen in food processing facilities

The rise and fall of the king : the correlation between FO Aquarii's low states and the White Dwarf's Spindown

The intermediate polar FO Aquarii experienced its first-reported low-accretion states in 2016, 2017, and 2018. We establish that these low states occurred shortly after the system's white dwarf (WD) began spinning down, after having spent a quarter-century spinning up. FO Aquarii is the only intermediate polar whose period derivative has undergone a sign change, and it has now done so twice. By combining our spin-pulse timings with previous data, we determine that the WD's spin period has varied quasi-sinusoidally since the system's discovery, and an extrapolation predicts that the white dwarf was spinning down during newly discovered low states in photographic plates from 1964, 1965, and 1974. Thus, FO Aquarii's low states appear to occur exclusively during epochs of spindown. Additionally, our time-series photometry of the 2016-18 low states reveals that the mode of accretion is extremely sensitive to the accretion rate; when the system is fainter than V~14.0, the accretion onto the WD is largely stream-fed, but when it is brighter, it is almost exclusively disk-fed. The system's grazing eclipse remained detectable throughout all observations, confirming the uninterrupted presence of a disk-like structure, regardless of the accretion state. Our observations are consistent with theoretical predictions that during the low states, the accretion disk dissipates into a ring of diamagnetic blobs. Finally, a new XMM-Newton observation from 2017 indicates that the system's anomalously soft X-ray spectrum and diminished X-ray luminosity in the wake of the 2016 low state appear to be long-lasting changes compared to pre-2016 observations.peer-reviewe