2,125 research outputs found

    Life-Cycle impacts of Inland Northwest and Northeast/North central forest resources

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    Determining the life-cycle inventory (LCI) and impact of forest harvest, regeneration, and growth is necessary in conducting a life-cycle assessment of wood products. This publication provides quantitative assessments of the economic and environmental impacts of forest management activities covering portions of the Inland Northwest (INW), including Montana, Idaho, and eastern Washington, and of the Northeastern and North Central (NE/NC) forests from Minnesota to Maine and south as far as Missouri, West Virginia, and Pennsylvania. The management scenarios provide the inputs needed to develop an LCI on all the inputs and outputs for wood products as impacted by forest treatments and the harvesting of logs in the region. Productive timberlands were grouped according to forest type, productivity, management intensity, and ownership into three broad forest types in the west: cold, dry, and moist; and four in the east: spruce/fir, northern hardwoods, oak/hickory, and aspen/birch. Spruce/fir represented the feedstock to softwood lumber and a composite of northern hardwoods and oak/hickory the feedstock to hardwood lumber. Simulations used the US Forest Service Forest Vegetation Simulator to estimate standing and harvested biomass and log volumes passed on as resources to the manufacturing segments for lumber, plywood, or oriented strandboard. The combinations of ownership, management intensity, and forest type were stratified and averaged to produce a single estimate of yield and the corresponding harvesting impacts. Both historic harvest rates and increased management intensity scenarios were simulated for each region. In the INW, the shift to the higher intensity scenario increased the average production of merchantable volume at harvest to 249 - 399 m3/ha when averaged across the forested land in each ownership class. For the NE/NC region, the production of merchantable volume averaged 263 m3/ha for softwood and 328 m3/ha for hardwood forests with an insignificant volume response from shifting land into more intensive management. Average growth varied widely for INW forest categories from a low on federal land for the base case of 0.7 - 6.7 m3/haha·yr for moist state and private land under the intensive management alternative. Current condition estimates of softwood log and bark carbon exported for mill processing in the INW and NE/NC regions were 751 and 988 kg/ha·yr, respectively

    The AP-2 adaptor β2 appendage scaffolds alternate cargo endocytosis

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    The independently folded appendages of the large α and β2 subunits of the endocytic adaptor protein (AP)-2 complex coordinate proper assembly and operation of endocytic components during clathrin-mediated endocytosis. The β2 subunit appendage contains a common binding site for β-arrestin or the autosomal recessive hypercholesterolemia (ARH) protein. To determine the importance of this interaction surface in living cells, we used small interfering RNA-based gene silencing. The effect of extinguishing β2 subunit expression on the internalization of transferrin is considerably weaker than an AP-2 α subunit knockdown. We show the mild sorting defect is due to fortuitous substitution of the β2 chain with the closely related endogenous β1 subunit of the AP-1 adaptor complex. Simultaneous silencing of both β1 and β2 subunit transcripts recapitulates the strong α subunit RNA interference (RNAi) phenotype and results in loss of ARH from endocytic clathrin coats. An RNAi-insensitive β2-yellow fluorescent protein (YFP) expressed in the β1 + β2-silenced background restores cellular AP-2 levels, robust transferrin internalization, and ARH colocalization with cell surface clathrin. The importance of the β appendage platform subdomain over clathrin for precise deposition of ARH at clathrin assembly zones is revealed by a β2-YFP with a disrupted ARH binding interface, which does not restore ARH colocalization with clathrin. We also show a β-arrestin 1 mutant, which engages coated structures in the absence of any G protein-coupled receptor stimulation, colocalizes with β2-YFP and clathrin even in the absence of an operational clathrin binding sequence. These findings argue against ARH and β-arrestin binding to a site upon the β2 appendage platform that is later obstructed by polymerized clathrin. We conclude that ARH and β-arrestin depend on a privileged β2 appendage site for proper cargo recruitment to clathrin bud sites

    Outpatient facility-based order variation in combined imaging.

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    OBJECTIVE: Combined computed tomography (CT) occurs when one anatomical area is simultaneously imaged both without and with contrast, or two overlapping anatomical areas are imaged concurrently. While this has been studied in a Traditional Medicare population, it has not been studied in other populations subject to prior authorization. This study explores between-facility variation in ordering and receiving orders to render combined CT in a mixed commercial and Medicare Advantage population. METHODS: Orders for CT abdomen (without/with contrast), CT thorax (without/with contrast), and concurrent CT brain and sinus authorized by a prior authorization company from 2013-2017, pertaining to patients with commercial or Medicare Advantage health plans from one national insurer, were extracted. Orders were issued and rendered by both hospitals and nonhospitals. The analysis was performed separately for each anatomical area in two ways: orders were grouped by ordering facility, and by designated rendering facility. For each facility, the ratio of combined to total orders was calculated, and analysis of variance was used to determine whether there were significant differences in this rate by year. The association between health plan type and combined imaging rates was assessed. RESULTS: Combined rates [ratio±standard deviation] for abdomen, thorax, and brain/sinus were 0.306±0.246, 0.089±0.142, and 0.002±0.01 respectively when the analysis was conducted according to ordering facility, and 0.311±0.178, 0.096±0.113, and 0.001±0.006 when the analysis was conducted according to designated rendering facility. Combined CT abdomen and CT thorax rates decreased monotonically from 2013 to 2017, decreases that were significant (P \u3c .01) regardless of whether orders were grouped by ordering or rendering facility. Combined CT abdomen and CT thorax rates significantly differed between orders pertaining to people with commercial and Medicare Advantage plans. DISCUSSION: Variability was greater when orders were grouped by ordering facility, rather than rendering facility. Health plan type may influence whether a patient receives combined CT

    Apathy Is Associated With Ventral Striatum Volume in Schizophrenia Spectrum Disorder

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    Apathy is prevalent in schizophrenia, but its etiology has received little investigation. The ventral striatum (VS), a key brain region involved in motivated behavior, has been implicated in studies of apathy. We therefore evaluated whether apathy is associated with volume of the VS on MRI in 23 patients with schizophrenia using voxel-based morphometry. Results indicated that greater self-reported apathy severity was associated with smaller volume of the right VS even when controlling for age, gender, depression, and total gray matter volume. The finding suggests that apathy is related to abnormality of brain circuitry subserving motivated behavior in patients with schizophrenia
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