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211.
Advances in digital technology and the growth of information networks are revolutionizing human activity. The Internet has been championed as a new tool for environmental improvement. A life-cycle energy analysis of digital libraries, a growing application of information technology, was conducted to test this premise.
Life-cycle models were compared for journal collections in digital and traditional formats. The basis for analysis was the amount of information in a typical scientific journal article (∼12 pages), which is equivalent to 0.97 hr of on-screen reading time. Digital system elements such as servers, routers, laser printers, and computer workstations were modeled. Journal production, delivery, storage, binding, interlibrary loan, and photocopying were examined for the traditional system. Building-related infrastructure, office paper, and personal transportation of the library patron were analyzed for both cases. In all, the study incorporated nearly 30 model elements, 90 input variables, and numerous fixed parameters.
Five primary scenarios were constructed to consider increasing levels of complexity. Scenario 1 assumes only one reading per article (unit of analysis). Additional scenarios assume 1,000 readings and vary the following: laser printing, photocopying, and personal transportation. Energy consumed by the digital collection ranged between 4.10 and 216 MJ. The traditional system realized burdens from 0.55 to 525 MJ. Four significant effects were uncovered: (1) Energy consumption per unit was highly influenced by the number of readings per article. (2) Networking infrastructure by itself had a relatively small effect on total energy consumed by the digital system. (3) When personal transportation was considered, its effects tended to dominate. (4) The impact of making personal copies varied. Photocopying always increased energy consumption, whereas laser printing actually saved energy when it substituted for on-screen reading. 相似文献
Life-cycle models were compared for journal collections in digital and traditional formats. The basis for analysis was the amount of information in a typical scientific journal article (∼12 pages), which is equivalent to 0.97 hr of on-screen reading time. Digital system elements such as servers, routers, laser printers, and computer workstations were modeled. Journal production, delivery, storage, binding, interlibrary loan, and photocopying were examined for the traditional system. Building-related infrastructure, office paper, and personal transportation of the library patron were analyzed for both cases. In all, the study incorporated nearly 30 model elements, 90 input variables, and numerous fixed parameters.
Five primary scenarios were constructed to consider increasing levels of complexity. Scenario 1 assumes only one reading per article (unit of analysis). Additional scenarios assume 1,000 readings and vary the following: laser printing, photocopying, and personal transportation. Energy consumed by the digital collection ranged between 4.10 and 216 MJ. The traditional system realized burdens from 0.55 to 525 MJ. Four significant effects were uncovered: (1) Energy consumption per unit was highly influenced by the number of readings per article. (2) Networking infrastructure by itself had a relatively small effect on total energy consumed by the digital system. (3) When personal transportation was considered, its effects tended to dominate. (4) The impact of making personal copies varied. Photocopying always increased energy consumption, whereas laser printing actually saved energy when it substituted for on-screen reading. 相似文献
212.
EDC3 phosphorylation regulates growth and invasion through controlling P‐body formation and dynamics
Jeremiah J Bearss Sathish KR Padi Neha Singh Marina CardoVila Jin H Song Ghassan Mouneimne Nikita Fernandes Yang Li Matthew R Harter Jaime MC Gard Anne E Cress Wolfgang Peti Andrew DL Nelson J Ross Buchan Andrew S Kraft Koichi Okumura 《EMBO reports》2021,22(4)
Regulation of mRNA stability and translation plays a critical role in determining protein abundance within cells. Processing bodies (P‐bodies) are critical regulators of these processes. Here, we report that the Pim1 and 3 protein kinases bind to the P‐body protein enhancer of mRNA decapping 3 (EDC3) and phosphorylate EDC3 on serine (S)161, thereby modifying P‐body assembly. EDC3 phosphorylation is highly elevated in many tumor types, is reduced upon treatment of cells with kinase inhibitors, and blocks the localization of EDC3 to P‐bodies. Prostate cancer cells harboring an EDC3 S161A mutation show markedly decreased growth, migration, and invasion in tissue culture and in xenograft models. Consistent with these phenotypic changes, the expression of integrin β1 and α6 mRNA and protein is reduced in these mutated cells. These results demonstrate that EDC3 phosphorylation regulates multiple cancer‐relevant functions and suggest that modulation of P‐body activity may represent a new paradigm for cancer treatment. 相似文献
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The results of bioassay and colony evaluation demonstrated that British and Texas Buckfast honey bee stocks had one-third to one-half the mean prevalence and abundance of tracheal mites as Canadian standard stock, indicating that Buckfast stocks are less susceptible to tracheal mites than Canadian standard stock. Hybrid Canadian and Buckfast stocks exhibited resistance characteristics similar to only one of their parental stocks, suggesting the colony has an unknown effect on the expression of a bee's resistance to mites. A high correlation (r
s=0.66) between abundance values from the bioassay and colony evaluations indicates that the bioassay can be used to screen bees for mite resistance. 相似文献
217.
P Locci R Evangelisti C Lilli E Becchetti P Carinci 《Cell biology international reports》1990,14(7):641-648
Incorporation of 3H glucosamine and 35SO4 into glycosaminoglycans and proteoglycans produced and secreted by 7, 11 and 14 day chick embryo fibroblasts in vitro after concanavalin A treatment has been determined. Lectin differently affects 3H and 35SO4 incorporation. It enhances 3H labelled GAG accumulation in both cellular and extracellular compartments. Total incorporation of 35SO4 remains unchanged whereas the intracellular one is stimulated and the extracellular is reduced. All the effects are more relevant in the early stages of development. HA and PG cellular and extracellular accumulation seems to be independently regulated. 相似文献