706 research outputs found
Analysis of the Socio-Environmental Impacts of the Proposed Transboundary Highway between Pucallpa, Peru and Cruzeiro do Sul, Brazil
As road building across the Amazon continues to be proposed by both Brazilian and Peruvian governments, it becomes increasingly important to consider the effects this infrastructure could have on diverse Amazonian cultures and ecosystems. One proposal being discussed is a 200 km road that would connect the cities of Pucallpa, Peru and Cruzeiro do Sul, Brazil. While promoted as economically beneficial, the road could infringe upon protected conservation areas and indigenous lands, bringing illegal activity with it as well. This research aims to evaluate the potential impacts the Pucallapa-Cruzeiro do Sul road project presents to the ecosystems, societies, and economies of the southwestern Amazon using a mixed methodology including geospatial analysis, remote sensing, and a literature review of previous studies on the impact of roads in tropical forests. These analyses will attempt to express the scale of the repercussions that road construction may bring to the bioculturally rich Amazon borderlands
Inter-Network Policy
Various embodiments associated an inter-network policy that is implemented for use across multiple networks are described. Individual networks can have individual policies that govern how communications are handled, how resources are allocated, and other metrics. When individual networks work together, these networks can experience problems if their individual policies conflict with one another. Therefore, the inter-network policy can be generated that facilitates the individual networks working together
Lipid Droplet Membrane Proteome Remodeling Parallels Ethanol-Induced Hepatic Steatosis and its Resolution
Lipid droplets (LDs) are composed of neutral lipids enclosed in a phospholipid monolayer, which harbors membrane-associated proteins that regulate LD functions. Despite the crucial role of LDs in lipid metabolism, remodeling of LD protein composition in disease contexts, such as steatosis, remains poorly understood. We hypothesized that chronic ethanol consumption, subsequent abstinence from ethanol, or fasting differentially affects the LD membrane proteome content and that these changes influence how LDs interact with other intracellular organelles. Here, male Wistar rats were pair-fed liquid control or ethanol diets for 6 weeks, and then, randomly chosen animals from both groups were either refed a control diet for 7 days or fasted for 48 h before euthanizing. From all groups, LD membrane proteins from purified liver LDs were analyzed immunochemically and by MS proteomics. Liver LD numbers and sizes were greater in ethanol-fed rats than in pair-fed control, 7-day refed, or fasted rats. Compared with control rats, ethanol feeding markedly altered the LD membrane proteome, enriching LD structural perilipins and proteins involved in lipid biosynthesis, while lowering LD lipase levels. Ethanol feeding also lowered LD-associated mitochondrial and lysosomal proteins. In 7-day refed (i.e., ethanol-abstained) or fasted-ethanol-fed rats, we detected distinct remodeling of the LD proteome, as judged by lower levels of lipid biosynthetic proteins, and enhanced LD interaction with mitochondria and lysosomes. Our study reveals evidence of significant remodeling of the LD membrane proteome that regulates ethanol-induced steatosis, its resolution after withdrawal and abstinence, and changes in LD interactions with other intracellular organelles
Lipid droplet membrane proteome remodeling parallels ethanol-induced hepatic steatosis and its resolution
Abstract Lipid droplets (LDs) are composed of neutral lipids enclosed in a phospholipid monolayer, which harbors membrane-associated proteins that regulate LD functions. Despite the crucial role of LDs in lipid metabolism, remodeling of LD protein composition in disease contexts, such as steatosis, remains poorly understood. We hypothesized that chronic ethanol consumption, subsequent abstinence from ethanol, or fasting differentially affects the LD membrane proteome content and that these changes influence how LDs interact with other intracellular organelles. Here, male Wistar rats were pair-fed liquid control or ethanol diets for 6 weeks, and then, randomly chosen animals from both groups were either refed a control diet for 7 days or fasted for 48 h before euthanizing. From all groups, LD membrane proteins from purified liver LDs were analyzed immunochemically and by MS proteomics. Liver LD numbers and sizes were greater in ethanolfed rats than in pair-fed control, 7-day refed, or fasted rats. Compared with control rats, ethanol feeding markedly altered the LD membrane proteome, enriching LD structural perilipins and proteins involved in lipid biosynthesis, while lowering LD lipase levels. Ethanol feeding also lowered LDassociated mitochondrial and lysosomal proteins. In 7-day refed (i.e., ethanol-abstained) or fasted-ethanolfed rats, we detected distinct remodeling of the LD proteome, as judged by lower levels of lipid biosynthetic proteins, and enhanced LD interaction with mitochondria and lysosomes. Our study reveals evidence of significant remodeling of the LD membrane proteome that regulates ethanol-induced steatosis, its resolution after withdrawal and abstinence, and changes in LD interactions with other intracellular organelles
Two DOT1 enzymes cooperatively mediate efficient ubiquitin-independent histone H3 lysine 76 tri-methylation in kinetoplastids
In higher eukaryotes, a single DOT1 histone H3 lysine 79 (H3K79) methyltransferase processively produces H3K79me2/me3 through histone H2B mono-ubiquitin interaction, while the kinetoplastid Trypanosoma brucei di-methyltransferase DOT1A and tri-methyltransferase DOT1B efficiently methylate the homologous H3K76 without H2B mono-ubiquitination. Based on structural and biochemical analyses of DOT1A, we identify key residues in the methyltransferase motifs VI and X for efficient ubiquitin-independent H3K76 methylation in kinetoplastids. Substitution of a basic to an acidic residue within motif VI (G
Powerful AGN jets and unbalanced cooling in the hot atmosphere of IC 4296
We present new Karl G. Jansky Very Large Array (VLA, 1.5 GHz) radio data for
the giant elliptical galaxy IC 4296, supported by archival radio, X-ray
(Chandra, XMM-Newton) and optical (SOAR, HST) observations. The galaxy hosts
powerful radio jets piercing through the inner hot X-ray emitting atmosphere,
depositing most of the energy into the ambient intra-cluster medium (ICM).
Whereas the radio surface brightness of the A configuration image is consistent
with a Fanaroff-Riley Class I (FR I) system, the D configuration image shows
two bright, relative to the central region, large (~160 kpc diameter),
well-defined lobes, previously reported by Killeen et al., at a projected
distance r~>230 kpc. The XMM-Newton image reveals an X-ray cavity associated
with one of the radio lobes. The total enthalpy of the radio lobes is ~7x10^59
erg and the mechanical power output of the jets is ~10^44 erg/s. The jets are
mildly curved and possibly re-brightened by the relative motion of the galaxy
and the ICM. The lobes display sharp edges, suggesting the presence of bow
shocks, which would indicate that they are expanding supersonically. The
central entropy and cooling time of the X-ray gas are unusually low and the
nucleus hosts a warm H\alpha+[NII] nebula and a cold molecular CO disk. Because
most of the energy of the jets is deposited far from the nucleus, the
atmosphere of the galaxy continues to cool, apparently feeding the central
supermassive black hole and powering the jet activity.Comment: Accepted for publication in MNRA
Strain Effects on the Work Function of an Organic Semiconductor
Establishing fundamental relationships between strain and work function (WF) in organic semiconductors is important not only for understanding electrical properties of organic thin films, which are subject to both intrinsic and extrinsic strains, but also for developing flexible electronic devices. Here we investigate tensile and compressive strain effects on the WF of rubrene single crystals. Mechanical strain induced by thermal expansion mismatch between the substrate and rubrene is quantified by X-ray diffraction. The corresponding WF change is measured by scanning Kelvin probe microscopy. The WF of rubrene increases (decreases) significantly with in-plane tensile (compressive) strain, which agrees qualitatively with density functional theory calculations. An elastic-to-plastic transition, characterized by a steep rise of the WF, occurs at ∼0.05% tensile strain along the rubrene π-stacking direction. The results provide the first concrete link between mechanical strain and WF of an organic semiconductor and have important implications for understanding the connection between structural and electronic disorder in soft organic electronic materials
Intraarticular location predicts cartilage filling and subchondral bone changes in a chondral defect: A randomized, blind, long-term follow-up trial involving 82 rabbit knees
Open Access - This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use,
distribution, and reproduction in any medium, provided the source is credited.Background and purpose: The natural history of, and predictive factors for outcome of cartilage restoration in chondral defects are poorly understood. We investigated the natural history of cartilage filling subchondral bone changes, comparing defects at two locations in the rabbit knee. Animals and methods: In New Zealand rabbits aged 22 weeks, a 4-mm pure chondral defect (ICRS grade 3b) was created in the patella of one knee and in the medial femoral condyle of the other. A stereo microscope was used to optimize the preparation of the defects. The animals were killed 12, 24, and 36 weeks after surgery. Defect filling and the density of subchondral mineralized tissue was estimated using Analysis Pro software on micrographed histological sections. Results: The mean filling of the patellar defects was more than twice that of the medial femoral condylar defects at 24 and 36 weeks of follow-up. There was a statistically significant increase in filling from 24 to 36 weeks after surgery at both locations. The density of subchondral mineralized tissue beneath the defects subsided with time in the patellas, in contrast to the density in the medial femoral condyles, which remained unchanged. Interpretation: The intraarticular location is a predictive factor for spontaneous filling and subchondral bone changes of chondral defects corresponding to ICRS grade 3b. Disregarding location, the spontaneous filling increased with long-term follow-up. This should be considered when evaluating aspects of cartilage restoration
The method of educational assessment affects children’s neural processing and performance: behavioural and fMRI Evidence.
Standardised educational assessments are now widespread, yet their development has given comparatively more consideration to what to assess than how to optimally assess students’ competencies. Existing evidence from behavioural studies with children and neuroscience studies with adults suggest that the method of assessment may affect neural processing and performance, but current evidence remains limited. To investigate the impact of assessment methods on neural processing and performance in young children, we used functional magnetic resonance imaging to identify and quantify the neural correlates during performance across a range of current approaches to standardised spelling assessment. Results indicated that children’s test performance declined as the cognitive load of assessment method increased. Activation of neural nodes associated with working memory further suggests that this performance decline may be a consequence of a higher cognitive load, rather than the complexity of the content. These findings provide insights into principles of assessment (re)design, to ensure assessment results are an accurate reflection of students’ true levels of competency
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