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991.
992.
Inclusion of carbonation during the life cycle of built and recycled concrete: influence on their carbon footprint 总被引:1,自引:0,他引:1
Frank Collins 《The International Journal of Life Cycle Assessment》2010,15(6):549-556
Background, aim, and scope
When the service life (or primary life) of built concrete infrastructure has elapsed, a common practice is that the demolished concrete is crushed and recycled, then incorporated into new construction. LCA studies of CO2 emissions focus on the manufacturing and construction and occupancy/utilization phases, without consideration of the demolition and application of recycled concrete into a secondary construction application. Concrete has a documented ability to chemically react with airborne carbon dioxide (CO2); however, carbon capture (or carbonation) by concrete during the primary and secondary life, is not considered in LCA models. This paper incorporates CO2 capture during both primary and secondary life into an LCA model for built concrete. 相似文献993.
Reinout Heijungs Raymond R. Tan 《The International Journal of Life Cycle Assessment》2010,15(9):1014-1019
Background, aim, and scope
Propagation of parametric uncertainty in life cycle inventory (LCI) models is usually performed based on probabilistic Monte Carlo techniques. However, alternative approaches using interval or fuzzy numbers have been proposed based on the argument that these provide a better reflection of epistemological uncertainties inherent in some process data. Recent progress has been made to integrate fuzzy arithmetic into matrix-based LCI using decomposition into α-cut intervals. However, the proposed technique implicitly assumes that the lower bounds of the technology matrix elements give the highest inventory results, and vice versa, without providing rigorous proof. 相似文献994.
995.
Sergio Rodríguez 《Biosemiotics》2016,9(2):169-184
This article addresses the semiotic problem of how meaning is agentially grounded: how actual meaning is possible and is justifiably supported by agents’ capabilities and purposes. This article is particularly focused on human agential grounding; however, to a great degree, insights presented here can be extended to other living beings. Specifically, agential meaning is examined here inside the framework of agentive semiotics and embodied, situated and enactive cognition theories, in line with the mind-life continuity general thesis (which intends to naturalize mind and experience). To offer clarity and methodological precision about agential grounding, three explanation categories (called recurrences) are proposed: phylogenetic recurrence, the evolutionary basis for corporal/embodied grounding; ontogenetic recurrence, the developmental basis for individual meaning grounding; and collective recurrence, the basis for meaning recognized, attributed and assigned inside social contexts. These recurrences are conceived as three types of general processes that constantly enclose possibilities for purpose and meaning emergence in humans. As a result of these types of recurrences, two categories of human agendas or purposes are also proposed: individual and collective. Finally, remarks about how these categories can be useful for semiotic analysis and further research are suggested. 相似文献
996.
997.
Journal of Mathematical Biology - Host heterogeneity can be modeled by using multi-group structures in the population. In this paper we investigate the existence and nonexistence of traveling waves... 相似文献
998.
Autophagy induction by xanthoangelol exhibits anti‐metastatic activities in hepatocellular carcinoma
Xiuwei Yang Jing Xie Xiaoxiao Liu Zichao Li Kun Fang Luying Zhang Mei Han Zhuang Zhang Zhi Gong Xuezhu Lin Xianzhou Shi Hui Gao Kui Lu 《Cell biochemistry and function》2019,37(3):128-138
Xanthoangelol (XAG), a prenylated chalcone isolated from the Japanese herb Angelica keiskei Koidzumi, has been reported to exhibit antineoplastic properties. However, the specific anti‐tumor activity of XAG in human hepatocellular carcinoma (HCC), and the relevant mechanisms are not known. Herein, we evaluated the effect of XAG against HCC in vitro and in vivo. Although XAG treatment did not significantly reduce the viability of the Hep3B and Huh7 cell lines, it suppressed cell migration, invasion, and EMT. This anti‐metastatic effect of XAG was due to induction of autophagy, because treatment with the autophagy inhibitor 3‐methyadenine (3‐MA) or knockdown of the pro‐autophagy Beclin‐1 effectively abrogated the XAG‐induced suppression of metastasis. Mechanistically, XAG induced autophagy via activation of the AMPK/mTOR signaling pathway, and XAG treatment dramatically increased the expression of p‐AMPK while decreasing p‐mTOR expression. In addition, blocking AMPK/mTOR axis with compound C abrogated the autophagy‐mediated inhibition of metastasis. The murine model of HCC metastasis also showed that XAG effectively reduced the number of metastatic pulmonary nodules. Taken together, our results revealed that autophagy via the activation of AMPK/mTOR pathway is essential for the anti‐metastatic effect of XAG against HCC. These findings not only contribute to our understanding of the anti‐tumor activity of XAG but also provide a basis for its clinical application in HCC. Before this study, evidence of XAG on HCC was purely anecdotal; present study provides the first comprehensive assessments of XAG on HCC metastasis and investigates its underlying mechanism. Results suggest that XAG exerts anti‐metastatic properties against HCC through inducing autophagy which is mediated by the activation of AMPK/mTOR signaling pathway. This research extends our knowledge about the antineoplastic properties of XAG and suggests that induction autophagy may represent future treatment strategies for metastatic HCC. 相似文献
999.
Jorge F. Toro-Vazquez Juan Morales-Rueda V. Ajay Mallia Richard G. Weiss 《Food biophysics》2010,5(3):193-202
In this research, we studied the relationship between the molecular structure of (R)-12-hydroxyoctadecanamide, (R)-N-propyl-12-hydroxyoctadecanamide, and (R)-N-octadecyl-12-hydroxyoctadecanamide and the thermo-mechanical properties of their 2% (wt/wt) organogels developed using safflower
oil high in oleic acid (HOSFO) as the liquid phase. Candelilla wax (CW), a well-known edible gelling additive whose main component
is hentriacontane, also was studied for comparative purposes. The results obtained show that the attractive interactions (i.e.,
hydrogen bonding and dipolar interactions) between amide groups and between hydroxyl groups present in the amides resulted
in organogels with higher melting temperature, heat of melting, and crystallization parameters than those found in the CW
organogel. The rheological parameters associated to the strength of the amide or CW-based gels developed in HOSFO (i.e., yield
stress and elastic modulus) seem to be associated with the nature of amide groups (i.e., primary or secondary amide) and the
increase in the length of the self-assembly molecular unit (i.e., L value determined by X-ray diffraction) and therefore to the extent of London dispersion forces along the hydrocarbon chain.
The creep and recovery measurements allowed an evaluation among the internal structures of the different organogels and demonstrated
that independent of the hydrogen bonding and dipolar interaction provided by the amide and the hydroxyl groups, the increase
in the hydrocarbon chain length results in higher organogel resistance to deformation and higher instant recovery capacity.
However, the stabilization of the self-assembly unit through polar groups (i.e., –CONH2 in HOA) reduces organogel elasticity but provides a higher extended recovery capacity. The results reported in this investigation
showed some relationships between gelator structure and the thermo-mechanical properties of low-molecular-mass organic gelator
amides. Our long-term objective is to understand the organogelation process to eventually develop trans-free vegetable oil-based food products with novel textures for the consumers. 相似文献
1000.
Karl-Erik Hammarberg 《Acta veterinaria Scandinavica》2002,43(Z1):S17
The new EU-regulations on organic farming (1804/1999) are also influencing the animal welfare. A lot of positive regulations is to find, but also regulations that seen to mind more about the general public and customer and their view on organic farming, than the health and welfare of the animals.The paper specially focus on the impact of the regulations and the recommendations that phytotherapeutic essences and homeopathic products take precedence over the so called chemically-synthesised allopatic veterinary medical products, and that the use of the same is prohibited for preventive treatments. Key questions here are the lack of scientific evidence concerning homeopathy in animals, and that Swedish veterinarians are not allowed to work with homeopathy.Differences in interpretation of the regulations between animal owners and veterinarians will also be discussed. What is a disease that needs treatment? Who is to decide about the treatment? Parasitic infections are discussed as an illustrative example.Other consequences of the regulations concerning the animal welfare are problems in certain geographical zones, for instance subarctic areas where necessary crops are impossible to grow.Animal transports and splitting mother-offspring are briefly discussed as future problems to be handled in the regulations, and the paper ends by presenting the need of regulated herd health control programs in organic husbandry, which can detect and focus on welfare and production problems. The organic movement is not static, and must not be so. 相似文献