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Sousa T Domingos T Poggiale JC Kooijman SA 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2010,365(1557):3413-3428
We present the state of the art of the development of dynamic energy budget theory, and its expected developments in the near future within the molecular, physiological and ecological domains. The degree of formalization in the set-up of the theory, with its roots in chemistry, physics, thermodynamics, evolution and the consistent application of Occam's razor, is discussed. We place the various contributions in the theme issue within this theoretical setting, and sketch the scope of actual and potential applications. 相似文献
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对产业生态学的基本概念、研究方法和研究热点进行了总结与评述,认为产业生态学是研究人类产业活动与自然环境相互关系的一门综合性、垮学科的应用科学。它采用工业代谢、生命周期评价和区域生态建设的方法对产业活动全过程(包括原材料采掘、原材料生产、产品制造、产品使用、产品用后处理)进行定性描述和定量模拟。产业生态学着眼于人类和生态系统的长远利益,追求经济效益、生态效益和社会效益的统一。 相似文献
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In the past decades a wide variety of tools have been developed to assess the sustainability performance of farms. Although multiple studies have compared tools on a theoretical basis, little attention has been paid to the comparing tools in practice. This research compared indicator-based sustainability assessment tools to gain insight in practical requirements, procedures and complexity involved in applying sustainability assessment tools. In addition, the relevance of the tools, as perceived by farmers, was evaluated. An overview of 48 indicator-based sustainability assessment tools was developed to, subsequently, select tools that address the environmental, social and economic dimension of sustainability, are issued in a scientific publication and suitable for assessing the sustainability performance of livestock and arable farms in Denmark. Only four tools (RISE, SAFA, PG and IDEA) complied with the selection criteria and were used to assess the sustainability performance of five Danish farms. The tools vary widely in their scoring and aggregation method, time requirement and data input. The farmers perceived RISE as the most relevant tool to gain insight in the sustainability performance of their farm. The findings emphasize the importance of context specificity, user-friendliness, complexity of the tool, language use, and a match between value judgements of tool developers and farmers. Even though RISE was considered as the most relevant tool, the farmers expressed a hesitation to apply the outcomes of the four tools in their decision making and management. Furthermore, they identified limitations in their options to improve their sustainability performance. Additional efforts are needed to support farmers in using the outcomes in their decision making. The outcomes of sustainability assessment tools should therefore be considered as a starting point for discussion, reflection and learning. 相似文献
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产业生态学的回顾与展望 总被引:30,自引:2,他引:30
对产业生态学的基本概念、研究方法和研究热点进行了总结与评述,认为产业生态学是研究人类产业活动与自然环境相互关系的一门综合性、垮学科的应用科学.它采用工业代谢、生命周期评价和区域生态建设的方法对产业活动全过程(包括原材料采掘、原材料生产、产品制造、产品使用、产品用后处理)进行定性描述和定量模拟.产业生态学着眼于人类和生态系统的长远利益,追求经济效益、生态效益和社会效益的统一. 相似文献
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Thomas Hartmann 《Plant Systematics and Evolution》1985,150(1-2):15-34
Plant metabolism may be devided in two functional levels: The level of primary metabolism, indispensible for growth and development, and the level of secondary metabolism covering the chemical interactions between organisms, indispensible for survival and maintaining of a species in its ecosystem. Arguments and evidence from various fields of biology are presented in favour of the idea that plant secondary metabolism has most important functions shaped by evolution: historical backgrounds; the difference between plant and animal organisation in respect to defense strategies; the main strategies of plant chemical defense against competitors, predators, and pathogens; complexity of secondary biosynthesis and metabolic integration; variability and richness of structures as essential attributes of secondary metabolism; differences between secondary and primary metabolism are functional not structural.
Vorgetragen auf der Tagung der Deutschen Botanischen Gesellschaft in Wien, September 1984. 相似文献
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Assessment of energetic condition is a critical tool for behavioral and reproductive ecologists. However, accurate quantification of energy intake and expenditure is labor-intensive, and it can be problematic for field scientists to obtain regular data on individual animals. C-peptide, a polypeptide segment of the proinsulin molecule that is secreted along with insulin in an equimolar relationship, can be measured in urine, and thus offers a potential means for the non-invasive assessment of energy balance in wild animals. Here, we validate C-peptide for the quantification of energetic condition, with specific application to wild orangutans (Pongo pygmaeus). We determined that application of urine to filter paper results in significantly lower C-peptide recoveries versus fresh samples. However, concentrations in filter paper samples were significantly correlated with fresh urine and were stable over various storage conditions and durations. We compared the C-peptide concentrations from wild orangutan urine samples with three independent measures of energetic condition: ketone bodies (urinalysis), caloric intake (nutritional biochemistry), and food availability (phenology). As expected, C-peptide concentrations were significantly lower in samples that tested positive for ketones in the field. Monthly average C-peptide concentrations of both male and female orangutans were significantly correlated with monthly determinations of energy intake and food availability. Therefore, we conclude that the collection and preservation of urine samples for C-peptide analysis are feasible under most field conditions and, in this species, presents a useful tool for assessing changes in energy balance. 相似文献
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Engel S Biebach H Visser GH 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2006,176(5):415-427
The metabolic costs of flight at a natural range of speeds were investigated in Rose Coloured Starlings (Sturnus roseus, Linnaeus) using doubly labelled water. Eight birds flew repeatedly and unrestrained for bouts of 6 h at speeds from 9 to 14 m s−1 in a low-turbulence wind tunnel, corresponding to travel distances between 200 and 300 km, respectively. This represents the widest speed range where we could obtain voluntarily sustained flights. From a subset of these flights, data on the wing beat frequency (WBF) and intermittent flight behaviour were obtained. Over the range of speeds that were tested, flight costs did not change with velocity and were on an average 8.17±0.64 W or 114 W kg−1. Body mass was the only parameter with a significant (positive) effect on flight costs, which can be described as EEf=0.741 M 0.554. WBF changed slightly with speed, but correlated better with body mass. Birds showed both types of intermittent flight, undulating and bounding, but their frequencies did not systematically change with flight speed. 相似文献
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This paper aims to highlight the considerable potential of a better integration of ecological theory in aquatic ecotoxicology. It outlines how community ecology, studies on trophic interaction and disturbance ecology could provide an enhanced theoretical basis for aquatic ecotoxicology and increase ecological relevance in environmental risk assessment of chemicals. Based on the literature and own research, approaches from aquatic ecotoxicology are presented, which are based on ecological considerations and address a higher level of biological complexity for risk assessment strategies of chemicals. The concepts of species-sensitivity distribution (SSD), pollution-induced community tolerance (PICT), the use of model ecosystems and the sediment quality triad (SQT) in ecological risk assesment as well as inputs from ecotoxicology into landscape ecology are illustrated. These examples aim to evidence aquatic ecotoxicology as a rewarding field of ecological research. 相似文献
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Abstract: The effects of nitroprusside and S -nitrosocysteine, compounds that generate nitric oxide (NO), on synaptosomal energy-producing pathways and energy level were investigated. The decrease in respiration was much faster and more pronounced with S -nitrosocysteine than with nitroprusside. S -Nitrosocysteine, at 10 µ M , inhibited by 80% respiration with glucose and succinate (plus rotenone) in intact synaptosomes and with ascorbate/cytochrome c in broken preparations. Oxygenated hemoglobin reversed and/or prevented the inhibition, whereas glutathione (GSH) prolonged it. Under aerobic conditions, the synaptosomal energy level (creatine phosphate/creatine and ATP/ADP ratios) was reduced by the presence of S -nitrosocysteine, whereas lactate generation was enhanced. The effects on energy parameters were greater at 5 min than at 15 min of incubation and were more pronounced in the presence of GSH. Under strictly anaerobic conditions, lactate production was reduced by the NO-generating compounds in a concentration-dependent manner. It is concluded that (a) inhibition of oxidative phosphorylation by NO leads to a fall in the synaptosomal energy level, which in turn stimulates glycolysis; (b) glycolysis can be inhibited by higher concentrations of the radical; and (c) inhibitory effects on the energy-generating pathway and ATP level could contribute to NO toxicity under some in vivo situations. 相似文献
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Synergistic protective effect of ischemic preconditioning and allopurinol on ischemia/reperfusion injury in rat liver 总被引:4,自引:0,他引:4
This study examined the effects of ischemic preconditioning (IPC), allopurinol (Allo) or a combination of both on the extent of mitochondrial injury caused by hepatic ischemia/reperfusion (I/R). I/R increased the serum aminotransferase activity and the level of mitochondrial lipid peroxidation, whereas it decreased the mitochondrial glutathione level. Either IPC or Allo alone attenuated these changes with Allo+IPC having a synergistic effect. Allo increased the serum nitrite and nitrate level after brief ischemia. The significant peroxide production observed after 10 min of reperfusion after sustained ischemia was markedly attenuated by Allo+IPC. The mitochondria isolated after I/R were swollen, which was reduced by Allo+IPC. At the end of ischemia, the hepatic ATP level was lower and there was significant xanthine accumulation, which was attenuated by Allo+IPC. These results suggest that IPC and Allo act synergistically to protect cells against mitochondrial injury and preserve the hepatic energy metabolism during hepatic I/R. 相似文献
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Michael Weisberg 《Biology & philosophy》2006,21(5):623-645
This paper is an interpretation and defense of Richard Levins’ “The Strategy of Model Building in Population Biology,” which
has been extremely influential among biologists since its publication 40 years ago. In this article, Levins confronted some
of the deepest philosophical issues surrounding modeling and theory construction. By way of interpretation, I discuss each
of Levins’ major philosophical themes: the problem of complexity, the brute-force approach, the existence and consequence
of tradeoffs, and robustness analysis. I argue that Levins’ article is concerned, at its core, with justifying the use of
multiple, idealized models in population biology.
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Michael WeisbergEmail: |
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Brittany Beauchamp A.?Brianne Thrush Jessica Quizi Ghadi Antoun Nathan McIntosh Osama?Y. Al-Dirbashi Mary-Elizabeth Patti Mary-Ellen Harper 《Bioscience reports》2015,35(3)
Intrauterine growth restriction (IUGR) is associated with an increased risk of developing obesity, insulin resistance and cardiovascular disease. However, its effect on energetics in heart remains unknown. In the present study, we examined respiration in cardiac muscle and liver from adult mice that were undernourished in utero. We report that in utero undernutrition is associated with impaired cardiac muscle energetics, including decreased fatty acid oxidative capacity, decreased maximum oxidative phosphorylation rate and decreased proton leak respiration. No differences in oxidative characteristics were detected in liver. We also measured plasma acylcarnitine levels and found that short-chain acylcarnitines are increased with in utero undernutrition. Results reveal the negative impact of suboptimal maternal nutrition on adult offspring cardiac energy metabolism, which may have life-long implications for cardiovascular function and disease risk. 相似文献
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Katrina R. Whitlow Francesco Santini Christopher E. Oufiero 《Journal of evolutionary biology》2019,32(1):76-88
Convergent evolution of a novel locomotor strategy implies that a fitness benefit may be associated with the new gait. Opportunities to study this phenomenon are often constrained by a lack of transitional taxa, but teleost fishes offer examples of extant species across such evolutionary shifts in gait. For instance, one species from Osteoglossiformes and the entire order of Gymnotiformes independently evolved a novel gait, gymnotiform locomotion, where thrust is produced by the undulation of an elongate anal fin. Here, we investigate whether this convergence in gait is also associated with similarities in shape, burst swimming abilities, and/or steady‐swimming energetics. Specifically, we measured body and fin morphology of fish within Gymnotiformes and Osteoglossiformes, along with closely related Siluriformes and Cypriniformes, to examine the link between gymnotiform locomotion and morphology in a phylogenetic context. Second, we tested the burst swimming capabilities and oxygen consumption during endurance swimming of a subset of the same gymnotiform, osteoglossiform, and cypriniform species, including “transitional” Osteoglossiformes that exhibit intermediate gaits, to determine whether the evolution of this specialized gait is associated with a change in either of these performance metrics. Our results suggest that convergence on the gymnotiform gait is associated with morphological convergence, but does not constrain a fish's maximum sprinting speeds or their energetic demands during steady swimming. 相似文献
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用量子力学观点阐明了生物的颜色和发光,讨论了生物的各种光化学和物理过程。这包括环境对发光的影响;分子内部的质子转移和异构化;血红蛋白的变构效应;激发态电荷转移的合成物;分子间的能量转移和电子转移;光分解和复合等。讨论了超快过程激光生物学的研究方法,这包括激光拉曼光谱法;荧光光谱法;吸收光谱法及偏振光谱法 相似文献
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Brain energy metabolism and mitochondrial dysfunction in acute and chronic hepatic encephalopathy 总被引:1,自引:0,他引:1
One proposed mechanism for acute and chronic hepatic encephalopathy (HE) is a disturbance in cerebral energy metabolism. It also reviews the current status of this mechanism in both acute and chronic HE, as well as in other hyperammonemic disorders. It also reviews abnormalities in glycolysis, lactate metabolism, citric acid cycle, and oxidative phosphorylation as well as associated energy impairment. Additionally, the role of mitochondrial permeability transition (mPT), a recently established factor in the pathogenesis of HE and hyperammonemia, is emphasized. Energy failure appears to be an important pathogenetic component of both acute and chronic HE and a potential target for therapy. 相似文献
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己酮可可碱对非酒精性脂肪性肝炎大鼠肝脏超微结构和酶组织化学的影响 总被引:1,自引:0,他引:1
目的研究己酮可可碱(PTX)对非酒精性脂肪性肝炎(NASH)大鼠肝脏超微结构和酶组织化学的影响。方法高脂饮食建立大鼠非酒精性脂肪性肝炎模型。取SD大鼠40只,分为对照组、12w模型组、16w模型组和治疗组,每组10只。腹主动脉采血,测ALT、AST、血糖等水平。取肝组织做电镜和SDH、CCO、ATPase、LDH的酶组织化学染色。结果两个模型组均比对照组ALT、AST、血糖升高,LDL降低(P<0.05)。治疗组血糖、AST比16w模型组降低(P<0.05)。电镜显示16w模型组线粒体肿大,嵴排列紊乱,基质密度降低。治疗组结构改善。酶组织化学显示四种酶的活性16w模型组均较对照组降低(P<0.05),治疗组活性均较16w模型组升高(P<0.05)。结论NASH时存在肝细胞能量代谢障碍,经PTX治疗后能量代谢障碍得到改善。 相似文献
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