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121.
Birth defects in infants born to employees of a microelectronics and business machine manufacturing facility 下载免费PDF全文
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E. Gregory McPherson Alissa Kendall 《The International Journal of Life Cycle Assessment》2014,19(9):1653-1665
Purpose
This study seeks to answer the question, “Will the Million Trees LA (Million Trees Los Angeles, MTLA) program be a carbon dioxide (CO2) sink or source?” Because there has never been a full accounting of CO2 emissions, it is unclear if urban tree planting initiatives (TPIs) are likely to be effective means for reaching local reduction targets.Methods
Using surveys, interviews, field sampling, and computer simulation of tree growth and survival over a 40-year time period, we developed the first process-based life cycle inventory of CO2 for a large TPI. CO2 emissions and reductions from storage and avoided emissions from energy savings were simulated for 91,786 trees planted from 2006 to 2010, of which only 30,813 (33.6 %) were estimated to survive.Results and discussion
The MTLA program was estimated to release 17,048 and 66,360 t of fossil and biogenic CO2 over the 40-year period, respectively. The total amount emitted (83,408 t) was slightly more than the ?77,942 t CO2 that trees were projected to store in their biomass. The MTLA program will be a CO2 sink if projected 40-year-avoided fossil fuel CO2 emissions from energy savings (?101,679 t) and biopower (?1,939 t) are realized. The largest sources of CO2 emissions were mulch decomposition (65.1 %), wood combustion (14.5 %), and irrigation water (9.7 %).Conclusions
Although trees planted by the MTLA program are likely to be a net CO2 sink, there is ample opportunity to reduce emissions. Examples of these opportunities include selecting drought-tolerant trees and utilizing wood residue to generate electricity rather than producing mulch. 相似文献123.
Abstract. Ultrastructural characteristics of the epidermis of 5 deep-sea vestimentiferan tube worms and an orbiniid worm were similar to those described from other organisms inhabiting sulfidic environments. The integument was composed of a simple or pseudostratified layer of columnar or cuboidal cells, covered by a cuticle of varying thickness, and rested on an extracellular matrix. Unusual mitochondrial morphology was observed in the peripheral region of the epidermis, characterized by an electron-dense matrix and granules. The abnormal size, shape, and reduced array of cristae in these mitochondria may have resulted from environmental stress. Mitochondria in the inner epidermal layers, where they are more protected from sulfide exposure, displayed normal morphology. The seep vestimentiferans ( Seepiophila jonesi and Lamellibrachia cf. luymesi ) exhibited numerous electron-dense organelles, similar in morphology to cytolysosomes and previously described as sulfide oxidizing bodies, while in the 3 vent vestimentiferans ( Riftia pachyptila, Tevnia jerichonana , and Oasisia alvinae ) and the seep orbiniid Methanoaricia dendrobranchiata , fewer of these organelles were observed. Energy dispersive x-ray microanalysis of these electron-dense organelles indicated the presence of sulfur, iron, zinc, and copper, as well as lesser amounts of other elements. We propose that these epidermal cytolysosomes are morphologically similar to previously described sulfide oxidizing bodies that have been hypothesized to play a role in maintaining aerobically poised animal metabolism in sulfide-enriched habitats. 相似文献
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Lung cancer is the leading cause of cancer deaths worldwide. If we can define and detect preneoplastic lesions, we might have a chance of improving survival. The World Health Organization has defined three preneoplastic lesions of the bronchial epithelium: squamous dysplasia/carcinoma in situ; atypical adenomatous hyperplasia; and diffuse idiopathic pulmonary neuroendocrine cell hyperplasia. These lesions are believed to progress to squamous cell carcinoma, adenocarcinoma and carcinoid tumors, respectively. In this review we summarize the data supporting the preneoplastic nature of these lesions, and delve into some of the genetic changes found in atypical adenomatous hyperplasia and squamous dysplasia/carcinoma in situ. 相似文献
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An array of emerging technologies, from electric vehicles to renewable energy systems, relies on large‐format lithium ion batteries (LIBs). LIBs are a critical enabler of clean energy technologies commonly associated with air pollution and greenhouse gas mitigation strategies. However, LIBs require lithium, and expanding the supply of lithium requires new lithium production capacity, which, in turn, changes the environmental impacts associated with lithium production since different resource types and ore qualities will be exploited. A question of interest is whether this will lead to significant changes in the environmental impacts of primary lithium over time. Part one of this two‐part article series describes the development of a novel resource production model that predicts future lithium demand and production characteristics (e.g., timing, location, and ore type). In this article, part two, the forecast is coupled with anticipatory life‐cycle assessment (LCA) modeling to estimate the environmental impacts of producing battery‐grade lithium carbonate equivalent (LCE) each year between 2018 and 2100. The result is a normalized life‐cycle impact intensity for LCE that reflects the changing resource type, quantity, and region of production. Sustained growth in lithium demands through 2100 necessitates extraction of lower grade resources and mineral deposits, especially after 2050. Despite the reliance on lower grade resources and differences in impact intensity for LCE production from each deposit, the LCA results show only small to modest increases in impact, for example, carbon intensity increases from 3.2 kg CO2e/kg LCE in 2020 to 3.3 kg CO2e/kg LCE in 2100. 相似文献
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Julian D Statile JL Wohlgemuth SE Arp AJ 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2002,133(1):105-115
At least some mammalian tissues produce H2S in vitro from L-cysteine at rates sufficient to have physiological effects. To determine whether tissues of macrofaunal invertebrates have the same capacity, we measured H2S production in tissue homogenates of the Manila clam Tapes philippinarum and the lugworm Arenicola marina. Tissue homogenates from both animals produced significant quantities of H2S gas upon addition of L-cysteine and the enzyme cofactor pyridoxal-5PRIME;-phosphate (10 mmol l(-1) and 2 mmol l(-1), respectively), while only tissues from T. philippinarum produced measurable H2S in the absence of added substrate or cofactor. In T. philippinarum tissues, H2S production was completely inhibited by the cystathionine beta-synthase (CBS) inhibitor aminooxyacetic acid (AOAA), suggesting that the majority of H2S production was via CBS pathways, while in A. marina body wall, AOAA inhibited only half of the total H2S production, indicating that the CBS pathway was not the only major source of H2S production. H2S production in tissues of T. philippinarum but not A. marina was doubled by the addition of a second thiol substrate (2.5 mmol l(-1) 2-mercaptoethanol), suggesting the presence of an 'activated serine sulfhydrase pathway', which had previously been demonstrated only in some microfauna. 相似文献
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