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Life cycle assessment (LCA) was combined with primary data from nine forest harvesting operations in New York, Maine, Massachusetts, and Vermont, from 2013 to 2019 where forest biomass (FB) for bioenergy was one of several products. The objective was to conduct a data‐driven study of greenhouse gas emissions associated with FB feedstock harvesting operations in the Northeast United States. Deterministic and stochastic LCA models were built to simulate the current FB bioenergy feedstock supply chain in the Northeast US with a cradle‐to‐gate scope (forest harvest through roadside loading) and a functional unit of 1.0 Mg of green FB feedstock at a 50% moisture content. Baseline LCA, sensitivity analysis, and uncertainty analyses were conducted for three different FB feedstock types—dirty chips, clean chips, and grindings—enabling an empirically driven investigation of differences between feedstock types, individual harvesting process contributions, and literature comparisons. The baseline LCA average impacts were lower for grindings (4.57 kg CO2eq/Mg) and dirty chips (7.16 kg CO2eq/Mg) than for clean chips (23.99 kg CO2eq/Mg) under economic allocation, but impacts were of similar magnitude under mass allocation, ranging from 24.42 to 27.89 kg CO2eq/Mg. Uncertainty analysis showed a wider range of probable results under mass allocation compared to economic allocation. Sensitivity analysis revealed the impact of variations in the production masses and total economic values of primary products of forest harvests on the LCA results due to allocation of supply chain emissions. The high variability in fuel use between logging contractors also had a distinct influence on LCA results. The results of this study can aid decision‐makers in energy policy and guide emissions reductions efforts while informing future LCAs that expand the system boundary to regional FB energy pathways, including electricity generation, transportation fuels, pellets for heat, and combined heat and power.  相似文献   
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Background aimsAdvanced therapy medicinal products (ATMP) have gained considerable attention in academia due to their therapeutic potential. Good Manufacturing Practice (GMP) principles ensure the quality and sterility of manufacturing these products. We developed a model for estimating the manufacturing costs of cell therapy products and optimizing the performance of academic GMP-facilities.MethodsThe “Clean-Room Technology Assessment Technique” (CTAT) was tested prospectively in the GMP facility of BCRT, Berlin, Germany, then retrospectively in the GMP facility of the University of California-Davis, California, USA. CTAT is a two-level model: level one identifies operational (core) processes and measures their fixed costs; level two identifies production (supporting) processes and measures their variable costs. The model comprises several tools to measure and optimize performance of these processes. Manufacturing costs were itemized using adjusted micro-costing system.ResultsCTAT identified GMP activities with strong correlation to the manufacturing process of cell-based products. Building best practice standards allowed for performance improvement and elimination of human errors. The model also demonstrated the unidirectional dependencies that may exist among the core GMP activities. When compared to traditional business models, the CTAT assessment resulted in a more accurate allocation of annual expenses. The estimated expenses were used to set a fee structure for both GMP facilities. A mathematical equation was also developed to provide the final product cost.ConclusionsCTAT can be a useful tool in estimating accurate costs for the ATMPs manufactured in an optimized GMP process. These estimates are useful when analyzing the cost-effectiveness of these novel interventions.  相似文献   
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Species face many threats, including accelerated climate change, sea level rise, and conversion and degradation of habitat from human land uses. Vulnerability assessments and prioritization protocols have been proposed to assess these threats, often in combination with information such as species rarity; ecological, evolutionary or economic value; and likelihood of success. Nevertheless, few vulnerability assessments or prioritization protocols simultaneously account for multiple threats or conservation values. We applied a novel vulnerability assessment tool, the Standardized Index of Vulnerability and Value, to assess the conservation priority of 300 species of plants and animals in Florida given projections of climate change, human land-use patterns, and sea level rise by the year 2100. We account for multiple sources of uncertainty and prioritize species under five different systems of value, ranging from a primary emphasis on vulnerability to threats to an emphasis on metrics of conservation value such as phylogenetic distinctiveness. Our results reveal remarkable consistency in the prioritization of species across different conservation value systems. Species of high priority include the Miami blue butterfly (Cyclargus thomasi bethunebakeri), Key tree cactus (Pilosocereus robinii), Florida duskywing butterfly (Ephyriades brunnea floridensis), and Key deer (Odocoileus virginianus clavium). We also identify sources of uncertainty and the types of life history information consistently missing across taxonomic groups. This study characterizes the vulnerabilities to major threats of a broad swath of Florida’s biodiversity and provides a system for prioritizing conservation efforts that is quantitative, flexible, and free from hidden value judgments.  相似文献   
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Shrub willow has great potential as a dedicated bioenergy crop, but commercialization and adoption by growers and end-users will depend upon the identification and selection of high-yielding cultivars with biomass chemistry and quality amenable to conversion to biofuels and bioenergy. In this study, critical traits for biomass production were evaluated among new genotypes of shrub willow produced through hybrid breeding. This study assessed the variation in yield, pest and disease resistance, biomass composition, and wood density in shrub willow, as well as the impact of genotypic and environmental factors on these particular phenotypes. Analysis of clonal genotypes established on two contrasting sites in New York State, Tully and Belleville, showed statistical differences by site for all of the traits. The greatest yield was observed at Belleville, NY, for two cultivars, ‘Fish Creek’ (41 Mg?ha?1) and ‘Onondaga’ (40 Mg?ha?1). Yields of Salix eriocephala genotypes were lowest, and they displayed susceptibility to rust and beetle damage. Variation in cellulose content in the stem biomass was controlled by environmental factors, with the majority of the genotypes displaying greater cellulose content at Belleville compared with Tully. In contrast, wood density was significantly greater at Tully than Belleville, and cellulose content was correlated with wood density. There were no significant correlations between biomass yield and density or any of the composition traits. These trials demonstrate that new genotypes produce improved yield and pest and disease resistance, with diverse compositional traits that can be matched with conversion technologies.  相似文献   
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Polyphenols contained in food have various positive effects on human health. The absorption and metabolism of polyphenols in the intestinal tract needs to be studied to estimate these effects. The Ussing chamber technique was used to investigate the transport behavior of apple polyphenols through pig small intestinal mucosa, which served as a model for human gastrointestinal mucosa. The identities and concentrations of polyphenols and their metabolites in the half-chambers (luminal and basolateral) within an incubation period of 4 h were determined by HPLC–MS/MS and HPLC–DAD (DAD = diode-array detection). Flux values were also measured. It was found that 5-caffeoylquinic acid and caffeic acid were absorbed and translocated to the basolateral side (1.9 and 3.7%, respectively), but other compounds, including glycosides of phloretin and quercetin, were observed without translocation. A Ussing chamber utilizing pig small intestinal mucosa is a suitable model for assessing the effect of apple polyphenols on mucosal integrity and nutrition absorption across porcine mucosa.  相似文献   
18.
BACKGROUND: The symptom triad of autosomal dominant Currarino syndrome (CS; MIM #176450) consists of anorectal malformation, a sacral bone defect, and presacral masses. Mutations in the homeoboxHLXB9 gene have already been described in a subset of sacrococcygeal anomalies characterized by partial sacral agenesis. CASE: We report a 28-year-old male patient with Currarino syndrome due to a heterozygous novel frame-shift mutation c.336dupG (p.P113fsX224) in the homeoboxHLXB9 gene. CONCLUSIONS: Molecular diagnostics may be helpful in cases of Hirschsprung's disease accompanied by other symptoms suggestive for Currarino syndrome, since it can lead to major complications such as perianal sepsis, meningitis, and malignant transformation.  相似文献   
19.
Prostaglandins (PG) are produced by the enzymatic activity of cyclooxygenase (COX). PGs and COX have been implicated in the pathophysiology of excitotoxicity and neurodegeneration in the central nervous system (CNS). The PGE2 receptor EP3 is the most abundantly expressed PGE2 receptor subtype in the brain. So far, in the innate rat brain EP3 receptors have been found exclusively in neurons. The aim of this study was to investigate whether EP3 expression in the brain changes under neurodegenerative circumstances such as an acute excitotoxic lesion. Intrastriatal injection of quinolinic acid (QUIN) resulted in a loss of EP3-positive striatal neurons, while simultaneously small glial-shaped EP3-positive cells appeared. Five days after lesioning, 63% of the glial-shaped EP3-positive cells could be identified as ED-1 expressing microglial cells. This percentage increased to 82% after 10 days, suggesting that most of the EP3-positive ED-1-negative cells on day 5 may be microglia which did not yet express ED-1. ED-1-positive microglia also expressed COX-1. These experiments show for the first time that activated microglial cells in excitotoxic lesions express in vivo the PGE2 receptor EP3 and the PGE2 synthesizing enzyme COX-1. Activation of EP3 receptor downregulates cAMP formation and may counteract the upregulation of cAMP formation via EP2 receptors, which has been linked to the anti-inflammatory effects of PGs. This change in EP3-receptor expression in microglia might participate in acute or chronic microglial activation in a variety of brain diseases such as ischemia or Alzheimer's disease (AD). Investigation of the expression of different PGE2 receptor subtypes might promote a better understanding of the pathophysiology of these diseases as well as leading to a modulation of microglial activation by a more specific interference with selective EP receptors than can be achieved by inhibiting global PG synthesis by selective or non-selective COX inhibitors.  相似文献   
20.
Drosophila proprioceptors (chordotonal organs) are structured as a linear array of four lineage-related cells: a neuron, a glial cell, and two accessory cells, called cap and ligament, between which the neuron is stretched. To function properly as stretch receptors, chordotonal organs must be stably anchored at both edges. The cap cells are anchored to the cuticle through specialized lineage-related attachment cells. However, the mechanism by which the ligament cells at the other edge of the organ attach is not known. Here, we report the identification of specialized attachment cells that anchor the ligament cells of pentascolopidial chordotonal organs (lch5) to the cuticle. The ligament attachment cells are recruited by the approaching ligament cells upon reaching their attachment site, through an EGFR-dependent mechanism. Molecular characterization of lch5 attachment cells demonstrated that they share significant properties with Drosophila tendon cells and with mammalian proprioceptive organs.  相似文献   
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