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Environmental Impacts of Wild Caught Cod and Farmed Salmon - A Comparison with Chicken (7 pp) 总被引:1,自引:0,他引:1
Harald Ellingsen Svein Aanond Aanondsen 《The International Journal of Life Cycle Assessment》2006,11(1):60-65
Goal, Scope and Background The objective of this study was to assess environmental impacts of Norwegian cod fishing and salmon farming and compare these
with chicken farming in order to find reference levels for environmental performance and identify problem areas and potentials
for improvements.
Methods A Life Cycle Screening following the production of 0.2 kg fillets as a functional unit through the respective food chains
is performed for all 3 products. The analysis is partly quantitative and qualitative focusing on energy use, antifouling and
land use impacts. Case studies are performed to investigate potentials for improvements within the fisheries and aquaculture
industry.
Results and Conclusions It can be concluded that the fishing phase for the cod and the feeding phase for both salmon and chicken dominate for all
environmental impacts considered. Chicken is most energy effective followed by salmon and cod, which are almost on the same
level. The area of sea floor affected by bottom trawling is around 100 times larger than the land area needed to produce the
chicken feed for production of the 0.2 kg fillet.
- The case studies show potentials for improvement of environmental performance, both for salmon farming and cod fishing, especially
when it comes to energy use. The environmental impacts on the sea floor imposed by bottom trawling are not fully explored,
but based on the precautionary principle a reasonable conclusion is that bottom trawls with less impact on the sea floor should
be developed.
Recommendation and Perspective LCA methods have initially been developed for land based industrial applications. More effort should be given to adapt these
to fishing applications in order to obtain more accurate assessment of environmental impacts from seafood products. It is
recommended to put more emphasis in finding improved indicators for impacts imposed by over-fishing, fuel emission from combustion
at sea, use of antifouling and seafloor ecosystem disturbance. 相似文献
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The formation of membraneless organelles (MLOs) by phase separation has emerged as a new way of organizing the cytoplasm and nucleoplasm of cells. Examples of MLOs forming via phase separation are nucleoli in the nucleus and stress granules in the cytoplasm. The main components of these MLOs are macromolecules such as RNAs and proteins. In order to assemble by phase separation, these proteins and RNAs have to undergo many cooperative interactions. These cooperative interactions are supported by specific molecular features within phase-separating proteins, such as multivalency and the presence of disordered domains that promote weak and transient interactions. However, these features also predispose phase-separating proteins to aberrant behavior. Indeed, evidence is emerging for a strong link between phase-separating proteins, MLOs, and age-related diseases. In this review, we discuss recent progress in understanding the formation, properties, and functions of MLOs. We pay special attention to the emerging link between MLOs and age-related diseases, and we explain how changes in the composition and physical properties of MLOs promote their conversion into an aberrant state. Furthermore, we discuss the key role of the protein quality control machinery in regulating the properties and functions of MLOs and thus in preventing age-related diseases. 相似文献
3.
V. Sholukha B. Bonnechere P. Salvia F. Moiseev M. Rooze S. Van Sint Jan 《Journal of biomechanics》2013
Modeling tools related to the musculoskeletal system have been previously developed. However, the integration of the real underlying functional joint behavior is lacking and therefore available kinematic models do not reasonably replicate individual human motion. In order to improve our understanding of the relationships between muscle behavior, i.e. excursion and motion data, modeling tools must guarantee that the model of joint kinematics is correctly validated to ensure meaningful muscle behavior interpretation. This paper presents a model-based method that allows fusing accurate joint kinematic information with motion analysis data collected using either marker-based stereophotogrammetry (MBS) (i.e. bone displacement collected from reflective markers fixed on the subject's skin) or markerless single-camera (MLS) hardware. This paper describes a model-based approach (MBA) for human motion data reconstruction by a scalable registration method for combining joint physiological kinematics with limb segment poses. The presented results and kinematics analysis show that model-based MBS and MLS methods lead to physiologically-acceptable human kinematics. The proposed method is therefore available for further exploitation of the underlying model that can then be used for further modeling, the quality of which will depend on the underlying kinematic model. 相似文献
4.
A wide range of cell types depend on mechanically induced signals to enable appropriate physiological responses. The skeleton is particularly dependent on mechanical information to guide the resident cell population towards adaptation, maintenance and repair. Research at the organ, tissue, cell and molecular levels has improved our understanding of how the skeleton can recognize the functional environment, and how these challenges are translated into cellular information that can site-specifically alter phenotype. This review first considers those cells within the skeleton that are responsive to mechanical signals, including osteoblasts, osteoclasts, osteocytes and osteoprogenitors. This is discussed in light of a range of experimental approaches that can vary parameters such as strain, fluid shear stress, and pressure. The identity of mechanoreceptor candidates is approached, with consideration of integrins, pericellular tethers, focal adhesions, ion channels, cadherins, connexins, and the plasma membrane including caveolar and non-caveolar lipid rafts and their influence on integral signaling protein interactions. Several mechanically regulated intracellular signaling cascades are detailed including activation of kinases (Akt, MAPK, FAK), β-catenin, GTPases, and calcium signaling events. While the interaction of bone cells with their mechanical environment is complex, an understanding of mechanical regulation of bone signaling is crucial to understanding bone physiology, the etiology of diseases such as osteoporosis, and to the development of interventions to improve bone strength. 相似文献
5.
Lagrangian Coherent Structures (LCS) of tandem wings hovering in an inclined stroke plane is studied using ImmersedBoundary Method (IBM) by solving two dimensional (2D) incompressible Navier-Stokes equations.Coherent structures responsible for the force variation are visualized by calculating Finite Time Lyapunov Exponents (FTLE),and vorticity contours.LCS is effective in determining the vortex boundaries,flow separation,and the wing-vortex interactions accurately.The effects of inter-wing distance and phase difference on the force generation are studied.Results show that in-phase stroking generates maximum vertical force and counter-stroking generates the least vertical force.In-phase stroking generates a wake with swirl,and counter stroking generates a wake with predominant vertical velocity.Counter stroking aids the stability of the body in hovering.As the hindwing operates in the wake of the forewing,due to the reduction in the effective Angle of Attack (AoA),the hindwing generates lesser force than that of a single flapping wing. 相似文献
6.
基于Web of Science数据库的检索结果,利用Histcite、Bibexcel和Netdraw对国际植被物候研究文献进行计量分析。结果表明:1 060篇相关文献刊载于288种期刊,平均载文3.68篇; 共分33个研究方向; 3 380位作者(第一作者904位)、69个国家或地区、1 172个组织参与; 国际合作发文310篇,占比29.25%; 其中中美合作居第一(19次)。分析还表明:2002~2007年是该领域重要发展期; 国际植被物候研究热点主要集中在基于气候(climate)-物候的田间局地观测和基于遥感(remote sensing)的大尺度物候研究。 相似文献
7.
Ezeji TC Qureshi N Blaschek HP 《Journal of industrial microbiology & biotechnology》2007,34(12):771-777
A potential industrial substrate (liquefied corn starch; LCS) has been employed for successful acetone butanol ethanol (ABE)
production. Fermentation of LCS (60 g l−1) in a batch process resulted in the production of 18.4 g l−1 ABE, comparable to glucose: yeast extract based medium (control experiment, 18.6 g l−1 ABE). A batch fermentation of LCS integrated with product recovery resulted in 92% utilization of sugars present in the feed.
When ABE was recovered by gas stripping (to relieve inhibition) from the fed-batch reactor fed with saccharified liquefied
cornstarch (SLCS), 81.3 g l−1 ABE was produced compared to 18.6 g l−1 (control). In this integrated system, 225.8 g l−1 SLCS sugar (487 % of control) was consumed. In the absence of product removal, it is not possible for C. beijerinckii BA101 to utilize more than 46 g l−1 glucose. A combination of fermentation of this novel substrate (LCS) to butanol together with product recovery by gas stripping
may economically benefit this fermentation.
Mention of trade names of commercial products in this article/publication is solely for the purpose of providing scientific
information and does not imply recommendation or endorsement by the United States Department of Agriculture. 相似文献
8.
Water is clearly important for the functioning of Photosystem II (PSII). Apart from being the very substrate that needs to be transported in this water oxidation enzyme, water is also vital for the transport of protons to and from the catalytic center as well as other important co-factors and key residues in the enzyme. The latest crystal structural data of PSII have enabled detailed analyses of the location and possible function of water molecules in the enzyme. Significant progress has also been made recently in the investigation of channels and pathways through the protein complex. Through these studies, the mechanistic significance of water for PSII is becoming increasingly clear. An overview and discussion of key aspects of the current research on water in PSII is presented here. The role of water in three other systems (aquaporin, bacteriorhodopsin and cytochrome P450) is also outlined to illustrate further points concerning the central significance that water can have, and potential applications of these ideas for continued research on PSII. It is advocated that water be seen as an integral part of the protein and far from a mere solvent. 相似文献
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