389 research outputs found
PREVALENCE RATE DIFFERENCES BASED ON HERDMATE COMPARISONS
A non-random survey of ovine progressive pneumonia (OPP) seropositive prevalence rates among 16,827 sheep in 29 states in the United states revealed large breed differences, a higher prevalence rate among older sheep and an unexplainable female rate that was more that three times the male rate. The herdmate comparison procedure, successfully used in evaluating dairy bulls, was adapted to compare the prevalence of a breed to the rate of its herdmates within herds. Likewise, sex and age differences in OPP prevalence were compared within herds that contained animals of both sexes and several ages. Using herdmate comparisons, breed and age differences in OPP prevalence remained but the sex difference disappeared
Differential Expression of Ovine Innate Immune Genes by Preterm and Neonatal Lung Epithelia Infected with Respiratory Syncytial Virus
Preterm infants have increased susceptibility to severe manifestations of respiratory syncytial virus (RSV) infection. The cause(s) for this age-dependent vulnerability is/are not well-defined, but alterations in innate immune products have been implicated. In sheep, RSV disease severity has similar age-dependent characteristics and sheep have several related innate molecules for study during pulmonary infection including surfactant protein A (SP-A), surfactant protein D (SP-D), sheep beta defensin 1 (SBD1), monocyte chemotactic protein 1 (MCP1), and Toll-like receptor 4 (TLR4). However, the in vivo cellular gene expression as a response to RSV infection is poorly understood. In this study, the effect of RSV infection on expression of these innate immune genes was determined for bovine RSV-infected (bRSV+ fluorescence) epithelial cells, adjacent cells lacking bRSV antigen (adjoining cells lacking fluorescence), and control cells from non-infected lung using laser capture microdissection (LCM) and real-time RT-PCR. Control lambs had increased expression of innate immune molecules in full term (term) compared to preterm epithelia with statistical significance in SBD1, SP-D, and TLR4 mRNA. Infected cells (bRSV+ fluorescent cells) had consistently higher mRNA levels of SP-A (preterm and term), MCP1 (preterm and term), and SP-D (preterm). Interestingly, bRSV- cells of infected term lambs had significantly reduced SP-D mRNA expression compared to bRSV+ and control epithelia, suggesting that RSV infected cells may regulate the adjacent epithelial SP-D expression. This study defines specific innate immune components (e.g., SBD1, SP-D, and TLR4) that have differential age-dependent expression in the airway epithelia. Furthermore, cellular bRSV infection enhanced certain innate immune components while suppressing adjacent cellular SP-D expression in term animals. These in vivo gene expression results provide a framework for future studies on age-dependent susceptibility to RSV and RSV pathogenesis
Heterogeneous CPU/GPU co-execution of CFD simulations on the POWER9 architecture: Application to airplane aerodynamics
High fidelity Computational Fluid Dynamics simulations are generally
associated with large computing requirements, which are progressively acute
with each new generation of supercomputers. However, significant research
efforts are required to unlock the computing power of leading-edge systems,
currently referred to as pre-Exascale systems, based on increasingly complex
architectures. In this paper, we present the approach implemented in the
computational mechanics code Alya. We describe in detail the parallelization
strategy implemented to fully exploit the different levels of parallelism,
together with a novel co-execution method for the efficient utilization of
heterogeneous CPU/GPU architectures. The latter is based on a multi-code
co-execution approach with a dynamic load balancing mechanism. The assessment
of the performance of all the proposed strategies has been carried out for
airplane simulations on the POWER9 architecture accelerated with NVIDIA Volta
V100 GPUs
Pleniglacial dynamics in an oceanic central European loess landscape
Loess–palaeosol sequences (LPSs) of the oceanic-influenced European loess belt underwent frequent post-depositional processes induced by surface runoff or periglacial processes. The interpretation of such atypical LPSs is
not straightforward, and they cannot be easily used for regional to
continental correlations. Within the last few years, however, such sequences
gained increased attention, as they are valuable archives for regional
landscape dynamics. In this study, the Siersdorf LPS was analysed using a
multi-proxy approach using sedimentological, geochemical, and
spectrophotometric methods combined with luminescence dating and tentative
malacological tests to unravel Pleniglacial dynamics of the Lower Rhine
Embayment. A marshy wetland environment for the late Middle Pleniglacial to
the early Upper Pleniglacial was shown by colour reflectance and grain size
distribution. Age inversions from luminescence dating paired with
geochemical and sedimentological data reveal long-lasting erosional
processes during the early Upper Pleniglacial, which were constrained to a
relatively small catchment with short transport ranges. The upper sequence
shows typical marker horizons for the study area and indicate harsh,
cold-arid conditions for the late Upper Pleniglacial. In comparison with
other terrestrial archives, the Siersdorf LPS shows that the Lower Rhine
Embayment was more diverse than previously assumed, regarding not only its
geomorphological settings and related processes but also its ecosystems and
environments.</p
Glycolysis Upregulation Is Neuroprotective As A Compensatory Mechanism In Als
Amyotrophic Lateral Sclerosis (ALS), is a fatal neurodegenerative disorder, with TDP-43 inclusions as a major pathological hallmark. Using a Drosophila model of TDP-43 proteinopathy we found significant alterations in glucose metabolism including increased pyruvate, suggesting that modulating glycolysis may be neuroprotective. Indeed, a high sugar diet improves locomotor and lifespan defects caused by TDP-43 proteinopathy in motor neurons or glia, but not muscle, suggesting that metabolic dysregulation occurs in the nervous system. Overexpressing human glucose transporter GLUT-3 in motor neurons mitigates TDP-43 dependent defects in synaptic vesicle recycling and improves locomotion. Furthermore, PFK mRNA, a key indicator of glycolysis, is upregulated in flies and patient derived iPSC motor neurons with TDP-43 pathology. Surprisingly, PFK overexpression rescues TDP-43 induced locomotor deficits. These findings from multiple ALS models show that mechanistically, glycolysis is upregulated in degenerating motor neurons as a compensatory mechanism and suggest that increased glucose availability is protective
Evolution of a minimal cell.
Na Publicação: D. M. C. Bittencourt
The unexpected resurgence of Weyl geometry in late 20-th century physics
Weyl's original scale geometry of 1918 ("purely infinitesimal geometry") was
withdrawn by its author from physical theorizing in the early 1920s. It had a
comeback in the last third of the 20th century in different contexts: scalar
tensor theories of gravity, foundations of gravity, foundations of quantum
mechanics, elementary particle physics, and cosmology. It seems that Weyl
geometry continues to offer an open research potential for the foundations of
physics even after the turn to the new millennium.Comment: Completely rewritten conference paper 'Beyond Einstein', Mainz Sep
2008. Preprint ELHC (Epistemology of the LHC) 2017-02, 92 pages, 1 figur
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