Academic literature on the topic 'Animals life cycles'
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Journal articles on the topic "Animals life cycles"
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Minelli, Alessandro, and Giuseppe Fusco. "Developmental plasticity and the evolution of animal complex life cycles." Philosophical Transactions of the Royal Society B: Biological Sciences 365, no. 1540 (2010): 631–40. http://dx.doi.org/10.1098/rstb.2009.0268.
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Metazoan life cycles can be complex in different ways. A number of diverse phenotypes and reproductive events can sequentially occur along the cycle, and at certain stages a variety of developmental and reproductive options can be available to the animal, the choice among which depends on a combination of organismal and environmental conditions. We hypothesize that a diversity of phenotypes arranged in developmental sequence throughout an animal's life cycle may have evolved by genetic assimilation of alternative phenotypes originally triggered by environmental cues. This is supported by similarities between the developmental mechanisms mediating phenotype change and alternative phenotype determination during ontogeny and the common ecological condition that favour both forms of phenotypic variation. The comparison of transcription profiles from different developmental stages throughout a complex life cycle with those from alternative phenotypes in closely related polyphenic animals is expected to offer critical evidence upon which to evaluate our hypothesis.
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Allen, Richard M., Anna Metaxas, and Paul V. R. Snelgrove. "Applying Movement Ecology to Marine Animals with Complex Life Cycles." Annual Review of Marine Science 10, no. 1 (2018): 19–42. http://dx.doi.org/10.1146/annurev-marine-121916-063134.
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Moran, N. A. "Adaptation and Constraint in the Complex Life Cycles of Animals." Annual Review of Ecology and Systematics 25, no. 1 (1994): 573–600. http://dx.doi.org/10.1146/annurev.es.25.110194.003041.
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Seksenova, D. U., B. K. Esimov, and Z. A. Ibragimova. "SARCOCYSTIS IN SOME RODENTS AND BIRDS." Series of biological and medical 2, no. 338 (2020): 56–61. http://dx.doi.org/10.32014/2020.2519-1629.13.
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Sarkosporidiosis is a chronic animal disease that often results in death. In animals with severe damage to the body by sarkosporidiosis, weakness, tissue depletion and hydremia are observed. Sarcocyst development occurs in muscle cells and tissues. It is known that in vivo predators become infected by eating meat from animals affected by sarcocysts. Sarcocysts secrete toxic substances, sarcocystin and sarcosporiocin, which lead to the death of animals within 5-20 hours. In chronic conditions in animals, salt deposits form around numerous sarcocysts and pronounced skeletal muscle hydremia is also observed. Sarcocystosis can be detected only after the death of animals. The corpses of animals must be examined microscopically, severely damaged corpses should be buried to a depth of 2 meters. When conducting microscopic studies of slices taken from samples of affected animal meat, a diagnosis is established. The proposed work is devoted to study the fauna and cycles of the development of micromorphology of representatives of the genus Sarcocystis of some rodents and birds. To achieve this research, an experiment was conducted with small vertebrates. The goal of our work is to identify the distribution of sarcosporidia of some species of rodents and birds, to study the morphology of the detected sarcosporidia, and their life cycle. The results of the study can be used for the epizootological characterization of sarcocystosis of rodents and birds. The study of the life cycle and specific structure is necessary for the diagnosis of species of the genus Sarcocystis. Yellow ground squirrel, house mouse and chukar can serve as a laboratory example in the study of mammalian and bird sarcocystosis. Ultrastructure materials and the life cycle of sarcosporidia can be used in studying the courses “Parasitology” and “Invertebrate Zoology”. There are 5 articles that were published on materials of this work.
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Payne, Jonathan L., Aviv Bachan, Noel A. Heim, Pincelli M. Hull, and Matthew L. Knope. "The evolution of complex life and the stabilization of the Earth system." Interface Focus 10, no. 4 (2020): 20190106. http://dx.doi.org/10.1098/rsfs.2019.0106.
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The half-billion-year history of animal evolution is characterized by decreasing rates of background extinction. Earth's increasing habitability for animals could result from several processes: (i) a decrease in the intensity of interactions among species that lead to extinctions; (ii) a decrease in the prevalence or intensity of geological triggers such as flood basalt eruptions and bolide impacts; (iii) a decrease in the sensitivity of animals to environmental disturbance; or (iv) an increase in the strength of stabilizing feedbacks within the climate system and biogeochemical cycles. There is no evidence that the prevalence or intensity of interactions among species or geological extinction triggers have decreased over time. There is, however, evidence from palaeontology, geochemistry and comparative physiology that animals have become more resilient to an environmental change and that the evolution of complex life has, on the whole, strengthened stabilizing feedbacks in the climate system. The differential success of certain phyla and classes appears to result, at least in part, from the anatomical solutions to the evolution of macroscopic size that were arrived at largely during Ediacaran and Cambrian time. Larger-bodied animals, enabled by increased anatomical complexity, were increasingly able to mix the marine sediment and water columns, thus promoting stability in biogeochemical cycles. In addition, body plans that also facilitated ecological differentiation have tended to be associated with lower rates of extinction. In this sense, Cambrian solutions to Cambrian problems have had a lasting impact on the trajectory of complex life and, in turn, fundamental properties of the Earth system.
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Overgaauw, Paul A. M. "Parasite risks from raw meat-based diets for companion animals." Companion Animal 25, no. 11 (2020): 261–67. http://dx.doi.org/10.12968/coan.2020.0065.
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In industrialised countries, dogs and cats are more often fed raw meat-based diets. There are microbial hazards associated with raw meat and these can introduce the risk of insufficient nutrition, as a result of nutritional imbalances and deficiencies. A literature review has been carried out to evaluate the risks of parasite infections in companion animals resulting from raw meat-based diets. Parasites present in raw meat use dogs and cats as part of their life cycle, these include protozoa such as Toxoplasma, Sarcocystis, Cystoisospora, Neospora and Hammondia; the nematodes Toxocara spp. and Trichinella; and the tapeworms Taenia spp., Echinococcus granulosus and E. multilocularis. Because of the lack of prevalence data, a valuable risk analysis is difficult. However, the life cycles demonstrate that eating raw meat-based diets and prey animals, can be a route of infection. Such agents can also be present in slaughtered animals. Infections can induce disease in intermediate hosts, but also in humans and other animal species, as an environment can be contaminated with oocysts or eggs. Several parasites can be transmitted via the alimentary route when raw meat-based diets are fed to companion animals. The best prevention method is to feed your companion animals commercial food or to cook meat and organs before feeding.
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Giraud, Tatiana, Lorys M. M. A. Villaréal, Frédéric Austerlitz, Mickaël Le Gac, and Claire Lavigne. "Importance of the Life Cycle in Sympatric Host Race Formation and Speciation of Pathogens." Phytopathology® 96, no. 3 (2006): 280–87. http://dx.doi.org/10.1094/phyto-96-0280.
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Numerous morphological species of pathogenic fungi have been shown to actually encompass several genetically isolated lineages, often specialized on different hosts and, thus, constituting host races or sibling species. In this article, we explore theoretically the importance of some aspects of the life cycle on the conditions of sympatric divergence of host races, particularly in fungal plant pathogens. Because the life cycles classically modeled by theoreticians of sympatric speciation correspond to those of free-living animals, sympatric divergence of host races requires the evolution of active assortative mating or of active host preference if mating takes place on the hosts. With some particular life cycles with restricted dispersal between selection on the host and mating, we show that divergence can occur in sympatry and lead to host race formation, or even speciation, by a mere process of specialization, with strong divergent adaptive selection. Neither active assortative mating nor active habitat choice is required in these cases, and this may explain why the phylo-genetic species concept seems more appropriate than the biological species concept in these organisms.
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Collet, Julie, and Simon Fellous. "Do traits separated by metamorphosis evolve independently? Concepts and methods." Proceedings of the Royal Society B: Biological Sciences 286, no. 1900 (2019): 20190445. http://dx.doi.org/10.1098/rspb.2019.0445.
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Despite the ubiquity of complex life cycles, we know little of the evolutionary constraints exerted by metamorphosis. Here, we present pitfalls and methods to answer whether animals with a complex life cycle can independently adapt to the environments encountered at each life stage, with a specific focus on the microevolution of quantitative characters. We first discuss challenges associated with study traits and populations. We further emphasize the benefits of using a combination of approaches. We then develop how multivariate methods can limit several issues by revealing genetic patterns that are invisible when only considering trait-by-trait genetic correlations. Finally, we detail how Lande's work on sexual dimorphism can be applied in measuring G matrices across life stages. The methods and tools described here will contribute towards building a predictive framework for trait evolution across life stages.
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McLaren, Ian A., Erica Head, and D. D. Sameoto. "Life cycles and seasonal distributions of Calanus finmarchicus on the central Scotian Shelf." Canadian Journal of Fisheries and Aquatic Sciences 58, no. 4 (2001): 659–70. http://dx.doi.org/10.1139/f01-007.
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The life cycle of Calanus finmarchicus on and around Western Bank, 19911992, was essentially annual; the overwintered generation (G0) produced G1 that developed at temperature-dependent rates and then largely disappeared after June to winter as late copepodids at depth. However, a small fraction of G1 matured to spawn a less rapidly developing G2 that outnumbered G1 in the depths of Emerald Basin in autumn 1990. Estimated mortality on the central Scotian Shelf for G1 from egg to copepodid stage 5 in June was ~4%·day1 but subsequently for G1 and G2 was nearly constant at ~1%·day1. Populations on Western Bank mostly derived from reproduction by overwintered G2 on the Scotian Shelf. Larger populations in Emerald Basin in 19871988 were augmented from advected animals enabled to diapause there at depth and on Emerald Bank by inputs from beyond the shelf break, ultimately from farther north. Our observations and analyses match the physical circulation in the region.
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Chang, Hung-Ming, Hsing-Chun Lin, Hsin-Lin Cheng, et al. "Melatonin Successfully Rescues the Hippocampal Molecular Machinery and Enhances Anti-oxidative Activity Following Early-Life Sleep Deprivation Injury." Antioxidants 10, no. 5 (2021): 774. http://dx.doi.org/10.3390/antiox10050774.
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Early-life sleep deprivation (ESD) is a serious condition with severe cognitive sequelae. Considering hippocampus plays an essential role in cognitive regulation, the present study aims to determine whether melatonin, a neuroendocrine beard with significant anti-oxidative activity, would greatly depress the hippocampal oxidative stress, improves the molecular machinery, and consequently exerts the neuro-protective effects following ESD. Male weanling Wistar rats (postnatal day 21) were subjected to ESD for three weeks. During this period, the animals were administered normal saline or melatonin (10 mg/kg) via intraperitoneal injection between 09:00 and 09:30 daily. After three cycles of ESD, the animals were kept under normal sleep/wake cycle until they reached adulthood and were sacrificed. The results indicated that ESD causes long-term effects, such as impairment of ionic distribution, interruption of the expressions of neurotransmitters and receptors, decreases in the levels of several antioxidant enzymes, and impairment of several signaling pathways, which contribute to neuronal death in hippocampal regions. Melatonin administration during ESD prevented these effects. Quantitative evaluation of cells also revealed a higher number of neurons in the melatonin-treated animals when compared with the saline-treated animals. As the hippocampus is critical to cognitive activity, preserving or even improving the hippocampal molecular machinery by melatonin during ESD not only helps us to better understand the underlying mechanisms of ESD-induced neuronal dysfunction, but also the therapeutic use of melatonin to counteract ESD-induced neuronal deficiency.
Dissertations / Theses on the topic "Animals life cycles"
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Distel, Christopher A. "Effects of an Insecticide on Competition in Anurans: Could Pesticide-Induced Competitive Exclusion be a Mechanism for Amphibian Declines?" Miami University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=miami1280363910.
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Ogino, Akifumi. "Life cycle assessment of Japanese animal production systems." Kyoto University, 2007. http://hdl.handle.net/2433/136678.
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Miranda, Edmund Richard. "Morphological constraints on life history evolution in Poecilia reticulata (Cyprinodontiformes: poeciliinae)." CSUSB ScholarWorks, 1999. https://scholarworks.lib.csusb.edu/etd-project/1722.
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Kumati, Osama B. Mohamed. "Virus life cycle and the parthenogenesis of malignant catarrhal fever." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/38034/.
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Malignant catarrhal fever (MCF) is caused by two closely associated gamma herpes viruses namely alcelaphine herpesvirus 1 (AlHV-1) and ovine herpesvirus 2 (OvHV-2) and characterised with lymphocyte infiltration in non-lymphoid tissues, vasculitis and epithelial damage. The mechanism by which the viruses cause the disease is not fully understood. The hypothesis of this project was that MCF is initiated by aberrant gene expression in endothelium, epithelium and infected T cells of susceptible animals, because they are not the natural hosts for the viruses and the viruses will not have evolved in them. The first goal was to examine whether rabbit epithelium and bovine endothelium can be infected in vitro and in vivo with AlHV-1 using q PCR and, if infected whether viral transcripts could be identified in these tissue cells using q PCR and in situ hybridisation (ISH). The results revealed that endothelium and epithelium can be infected and latent infection can be established in them. This suggests the likelihood of establishing a similar type of infection in vivo. Secondly, the trial to identify latency-associated transcripts using 5-azacitidine treatment on bovine turbinate fibroblast (BT) cells and rabbit large granular lymphocytes (LGLs) was only partially successful. However, pan T antigen was expressed in 5-azacitidine treated but not untreated LGLs cells. This may indicate a function of the drug either directly or through the latency state. Transcriptome analysis in the infected and treated LGLs and BT cells showed that several pathways were affected by 5-aza although a possible latency (low transcript levels) was only seen in the BTs. Transcriptome analysis revealed similar pathways to those described for MCF in the tissues in vivo, and an effect of 5-aza on these. Viral transcripts analysis showed that genes related to productive/lytic cycles were higher than latent ones on day 17 of the in vivo experiment demonstrating that the virus may replicate at this stage of the disease. The attempt to localize the viral transcripts on the rabbit infected tissues using ISH was unsuccessful due to a lack of time.
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Cederberg, Christel. "Life cycle assessment (LCA) of animal production : thesis for the degree of doctor of philosophy /." Göteborg : Göteborg University, 2002. http://catalogue.bnf.fr/ark:/12148/cb39984339n.
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Ford, Matthew Jonathan. "Design and implementation of transgenic tools to visualise cell cycle progression in mammalian development." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/23658.
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Cell cycle progression is the series of steps a cell has to take in order to duplicate its DNA and produce two daughter cells. Correct spatial and temporal coordination of the cell cycle is key for the normal development of any organ or tissue and is stringently controlled during embryogenesis and homeostasis. Misregulation of cell cycle progression is causal in many developmental disorders and diseases such as microcephaly and cancer. Fucci (Fluorescent Ubiquitination based Cell Cycle Indicator) is a system that allows for the visualisation of cell cycle progression by the use of two differently coloured fluorescent probes whose abundance is regulated reciprocally during the cell cycle. The probes contain the E3 ligase recognition domains of Cdt1 and Geminin fused to the fluorophores mCherry (red fluorescence) and mVenus (yellow fluorescence) respectively. Cells are therefore labelled red during G1, yellow in the G1/S transition and green during late S/G2 and M phases of the cell cycle. In order to study development and tissue homoeostasis a Fucci expressing mouse line was developed however this has several key limitations: First, the two Fucci probes are expressed from separate loci complicating mouse colony maintenance. Second, the constructs were not inducible, making it impossible to follow cell cycle progression in specific cell lineages and third the mice were generated by random transgenesis which is prone to silencing and can exhibit variation in expression between different tissues. Here I have characterised an improved version of the original Fucci system known as Fucci2a designed by Dr Richard Mort (University of Edinburgh) to overcome these limitations. The Fucci2a genetic construct contains both Fucci probes fused with the Thosea asigna virus self-cleaving peptide sequence T2A. This allows expression of both probes as a single bicistronic mRNA with subsequent cleavage by ribosomal ‘skipping’ during translation to yield separate proteins. A Fucci2a mouse (R26Fucc2aR) was generated by homologous recombination into the ROSA26 locus using the strong, ubiquitous CAG promoter to drive expression and incorporating a floxed-Neo stop cassette. This allows tissue specific activation by Cre recombinase when combined with a second Cre expressing mouse line. Building on the bicistronic Fucci2a technology I have gone on to develop and characterise four new tricistronic reporter constructs which allow for the dual visualisation of cell cycle progression with apoptosis, cytokinesis and ciliogenesis. In each case an additional fluorescent probe was added to the original Fucci2a construct separated by the self-cleaving peptide P2A and the construct characterised in 3T3 stable cell lines. The combination of a dual cilia and cell cycle reporter construct proved fruitful and I have gone on to investigate the relationship between cell cycle progression and ciliogenesis in 3T3 cells and have generated and characterised the R26Arl13b-Fucci2aR mouse line. I have also illustrated the utility of the R26Fucci2aR mouse for generating quantitative data in development research in two development situations; melanocyte development and lung branching morphogenesis. Melanocytes are specialised melanin producing cells responsible for the pigmentation of the hair, skin and eyes. Their precursors, melanoblasts, are derived from the neural crest where they migrate and proliferate before becoming localised to hair follicles and their study provides a good model for understanding the development of other neural crest derived lineages such as the peripheral nervous system. Using time-lapse imaging of ex vivo skin cultures in which melanoblasts are labelled with the Fucci probes I have characterised melanoblast migration and proliferation. In addition, I have shown that Kit signalling, which is necessary for melanoblast migration and survival, controls melanoblast proliferation in a density dependent manner and that melanoblast migration is more persistent in S/G2/M phases of the cell cycle. Lung branching morphogenesis requires constant proliferation at the apical tip of a growing epithelial branch. Loss of epithelial symmetry through an unidentified mechanism (requiring BMP, FgF10, Shh and Wnt signalling) within a branch is required to initiate branching either latterly from the side of a elongating branch by domain branching or by bifurcation of the tip. In the final section of this thesis I performed a comparative analysis of the behaviour of the developing lung epithelium using proliferative status (Fucci2a expression) to categorise each cell. Using a combination of live imaging and immunohistochemistry I have identified a transition zone 100-150μm from the tip of the branching lung epithelium where epithelial cells become stationary and drop out of the cell cycle corresponding with the onset of proximal bronchial progenitor marker Sox2. A comparative gene expression analysis of the proliferating and non-proliferating regions using Fucci2a to distinguish them has eluded to several interesting genes which could influence branching morphogenesis during lung development.
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Nogueira, Alex Rodrigues. "Avaliação do desempenho ambiental de biodiesel produzido a partir de gordura animal segundo diferentes abordagens para situaçõees de multifuncionalidade." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-14032018-151811/.
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O Brasil é um país que se destaca pela pujança da pecuária e como importante ator no mercado de biodiesel. Entretanto, há uma carência de estudos que investiguem o desempenho ambiental do biodiesel produzido a partir de gordura animal segundo uma lógica sistêmica. Trata-se de um tema controverso em função do tratamento dado à gordura pois, embora haja demanda e mercado bem estabelecido, há casos em que esta substância é tratada como um rejeito da produção de carne, desconsiderando-se os impactos ambientais pregressos. Neste contexto, o presente trabalho foi desenvolvido com o objetivo de avaliar a criticidade de diferentes abordagens para as situações de multifuncionalidade da cadeia de produção do biodiesel obtido de gordura animal. Para tanto, fez-se uso da técnica de Avaliação do Ciclo de Vida de produtos segundo o enfoque atribucional com escopo do \"berço-ao-portão\" para se determinar o desempenho do biodiesel produzido nas regiões Sul, Centro-Oeste e Sudeste, e disponibilizado (tanto puro quanto na forma das misturas B15 e B8) para a região metropolitana de São Paulo entre os anos de 2013 e 2015. As situações de multifuncionalidade foram analisadas a partir da aplicação de critérios físicos (proporção mássica e conteúdo energético), de critérios econômicos e do Método Surplus, além da expansão das fronteiras do sistema e substituição de cargas ambientais evitadas. Os resultados foram expressos em termos das categorias de impacto de Mudanças Climáticas, Acidificação terrestre, Eutrofização aquática, Formação fotoquímica de oxidantes, Demanda de Energia Primária. Adicionalmente, foram feitas considerações a respeito do indicador de Energy Return On Investment (EROI) e do balanço de emissões de gases de efeito estufa. Os resultados indicaram que a alocação das cargas ambientais do processo de refino de petróleo - para a produção do diesel fóssil usado em atividades de transporte - mostrou-se irrelevante no contexto do presente estudo. No que diz respeito ao processo de transesterificação, os efeitos das abordagens para as situações de multifuncionalidade foram pouco influentes sobre os resultados. Isto porque a magnitude do impacto da atividade pecuária foi tamanha que a amplitude dos resultados variou cerca de 817 vezes (no caso da categoria de Mudanças Climáticas) ou até 1084 vezes (para a Demanda de Energia Primária).Brazil is a country that stands out for the internal importance of cattle farming and as an important player in the biodiesel market. However, there is a lack of studies focusing the investigation of the environmental performance of biodiesel produced from animal tallow according to a systemic scope. This is a controversial issue, due to the treatment given to tallow as, although there is consistent market demand, there are cases in which this substance is treated as a waste from meat production activities. In this context, this study was conducted aiming the evaluation of the criticality of different approaches to multifunctional situations of the biodiesel production chain from animal tallow. In order to do so, attributional Life Cycle Assessment technique was used according to a \"cradle-to-gate\" scope in order to determine the environmental performance of biodiesel produced in the South, Midwest and Southeast regions, and commercialized (either purely or in the form of B15 and B8 mixtures) at São Paulo metropolitan region between 2013 and 2015. Multifunctionality situations were analyzed based on the application of physical criteria (mass ratio and energy content), economic criteria and the Surplus Method, as well as based on system boundaries expansion and the substitution of avoided environmental burdens. The results were expressed in terms of the following impact categories: Climate Change, Terrestrial Acidification, Aquatic Eutrophication, Photochemical Oxidants Formation, and Primary Energy Demand. In addition, considerations were made regarding the Energy Return On Investment (EROI) indicator and the greenhouse gases emission balance. The results indicated that the allocation of environmental burdens at petroleum refining process - for the production of fossil diesel used in transport activities - proved to be irrelevant in the context of the present study. Regarding the transesterification process, the effects of the approaches for multifunctionality situations were not very influential on the results. This is because the magnitude of the impact of cattle raising activity was such that the results varied by about 817 times (in the case of the Climate Change impact category) or up to 1084 times (considering the Primary Energy Demand).
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Ramos, Daniela Maria Justino Alves. "Intraspecific agonistic behaviour during settlement events of a marine invertebrate with a biphasic life cycle." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/16834.
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Mestrado em Ecologia AplicadaCannibalism is a well-known behaviour among several invertebrate marine species and may play a relevant role in population dynamics and distribution. In this study we tested if this behaviour occurs at key moments of the complex life cycle of a decapod, namely at settlement and early post-metamorphosis. We collected wild megalopae of the brachyuran crab Carcinus maenas at Ria de Aveiro (Portugal) and at laboratory conditions tested the survival of megalopae stocked at different densities and under contrasting conditions of habitat and food availability. We also tested if cannibalism could be observed between megalopae and first, second and third instar juvenile crabs. Our results showed that megalopae only display cannibalism towards conspecifics at the same life stage under high densities scenarios. The occurrence of cannibalism towards megalopae was immediate and more significant with juveniles on the third crab stage (C3) when compared with the first and second juvenile crab stage (C1 and C2). This study allowed to perceived that during high settlement peaks, the performance and survival of megalopae is not affected by possible cannibalistic interactions among other megalopae. However, the structure and number of the adult population may not correspond to the potential settlement of the larvae when conspecifics of previous events, such as juvenile C3 are present in the same place, due to occurrence of cannibalism.
O canibalismo é um comportamento intraespecífico observado entre muitas espécies de invertebrados marinhos, introduzindo alterações na dinâmica e distribuição das populações. Neste estudo pretendemos testar se este comportamento pode ser observado durante o assentamento e pós-assentamento de um decápode com um ciclo de vida complexo. Megalopas selvagens do caranguejo braquiúro Carcinus maenas foram recolhidas na Ria de Aveiro (Portugal) e em condições de laboratório, testou-se a sua sobrevivência quando expostas a diferentes densidades, complexidade de habitat e disponibilidade de alimento. Foi também testada a ocorrência de canibalismo dos três primeiros estágios de juvenis para com conspecíficos no estado larvar de megalopa. Os resultados experimentais revelaram que o canibalismo não é comum entre megalopas, sendo apenas influenciado quando estão presentes em grandes densidades. Os juvenis no terceiro estágio de caranguejo (C3) apresentaram comportamentos canibalísticos imediatos e mais significativos quando comparados com os juvenis do primeiro e segundo estágio de caranguejo (C1 e C2). Os resultados apresentados permitiram deste modo perceber que durante elevados picos de assentamento, o desempenho e sobrevivência das megalopas não é afetado por possíveis comportamentos canibalísticos entre estas. No entanto, a estrutura das populações adultas pode não corresponder ao potencial de assentamento das larvas quando coespecíficos de eventos anteriores, como por exemplo, juvenis C3, se encontram presentes no mesmo local, devido à ocorrência de canibalismo.
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Roffeis, Martin. "Implementing Insect Production in Agricultural Value Chains: An ex-ante life cycle evaluation." Doctoral thesis, Universite Libre de Bruxelles, 2019. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/285521.
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Résumé Une demande croissante sans cesse de produits alimentaires à base d’animaux influence la productivité des systèmes mondiaux de production alimentaire, et des mesures indispensables pour freiner la dégradation de l’environnement promettent des effets similaires. Si les scénarios de demande future peuvent être satisfaits de manière durable, cela dépend notamment de la possibilité de réduire de manière significative l'impact de l'aquaculture et de l'élevage sur l'environnement. Des recherches récentes suggèrent que l'utilisation d'aliments à base d'insectes (IBF) pourrait apporter une contribution significative à cet égard, et des arguments valables sont avancés pour soutenir cette hypothèse. Les larves de mouches, comme celles des mouches domestiques (Musca domestica) ou des mouches soldat noir (Hermetia illucens), sont en mesure de puiser des nutriments dans un large éventail de ressources organiques, y compris celles impropres à la consommation humaine. Cela crée la possibilité de convertir (et de réduire considérablement) les déchets organiques de faible valeur, tels que le fumier ou le sang animal, en protéines de haute qualité et en énergie alimentaire, qui se sont avérés appropriés pour nourrir différents poissons d'aquaculture et du bétail monogastrique.Bien que le concept IBF promet d’importants avantages et ait démontré sa faisabilité technique, il n’existe encore aucun système établi permettant de tester les avantages supposés en termes de durabilité. Dans cette thèse, nous avons essayé de surmonter cette lacune par la modélisation de tels systèmes. Notre objectif central était d'identifier les aspects influençant le potentiel d'application des IBF dans différents contextes géographiques et de définir des voies d'optimisation pour une mise en œuvre durable. En nous basant sur des données expérimentales recueillies lors d'essais d'élevage menés en Europe (Espagne et Slovaquie) et en Afrique de l'Ouest (Ghana et Mali), nous avons formulé la conception d'un ensemble de versions de systèmes améliorés élevant M. domestica et H. illucens sur différents substrats organiques de faible valeur. Les modèles de production génériques ont servi comme base d’une analyse du cycle de vie ex ante, dans laquelle nous avons exploré les performances des systèmes à l’aide d’analyse du cycle de vie environnementale (ACV) et de l’analyse des coûts du cycle de vie (ACCV).Les ACVs et ACCVs ont montré que les performances environnementales et économiques des IBF sont largement fonction de l’efficacité de conversion des systèmes, de l’organisation du processus de production (c’est-à-dire de l’apport de main-d’œuvre et d’équipements technologiques) et du contexte géographique. La combinaison de ces facteurs a fourni des avantages pour les configurations simplistes utilisées dans la production de M. domestica en Afrique occidentale tropicale dans des conditions de ponte naturelle (c'est-à-dire d'inoculation de substrat par le biais de mouches présentes à l'état naturel). L'inoculation artificielle (c'est-à-dire l'inoculation du substrat par le biais de larves nourries provenant d'une colonie d'adultes en captivité), utilisée dans la production de H. illucens en Afrique de l'Ouest et de M. domestica dans le sud de l'Espagne, a favorisé une efficacité de conversion élevée, mais a augmenté les impacts environnementaux et les coûts, parce que le système complexe et l'organisation de processus à forte intensité de main-d'œuvre ont considérablement accru les intrants de main-d'œuvre et d'infrastructures de production.Une comparaison avec des aliments conventionnels riches en protéines a mis en évidence des inconvénients environnementaux et économiques pour les modèles de production actuels des IBF, notamment en ce qui concerne les aliments végétaux (par exemple, le tourteau de soja). Les disparités entre les alimentations IBF et conventionnelles reflètent l’utilisation des capacités sub-optimaux des systèmes (effet d’économie d’échelle insuffisant), ainsi que la perte d’énergie et de biomasse le long de la chaîne trophique (producteurs autotrophes vs consommateurs hétérotrophes). Les résultats soulèvent des doutes légitimes sur les avantages en termes de durabilité d’une mise en œuvre d'insectes dans les chaînes de valeur agricoles actuelles. Le succès commercial dépend en grande partie du niveau de salaire spécifique au contexte, des prix des substrats d'élevage et de la manière dont les marchés évaluent les multiples fonctions que les insectes sont capables de fournir. S'agissant de la performance environnementale, nos résultats nous amènent à conclure que la production d'IBF ne présente aucun avantage par rapport aux aliments conventionnels.L’évaluation de systèmes de production encore hypothétiques impliquait une bonne quantité d’hypothèses et d’approximations. Étant donné ces multiples sources d'incertitude et compte tenu du fait que seul un nombre limité de conceptions de systèmes possibles sont prises en compte, les déclarations sur le potentiel d'application d'IBF n'ont aucune validité universelle et doivent être interprétées avec prudence. Cependant, nos résultats contribuent à une meilleure compréhension des facteurs influant sur le potentiel d’application des systèmes de production d’insectes et constituent un point de référence précieux pour les discussions scientifiques et les activités de recherche et développement futures visant à mettre en place des modes de production alimentaire durables.Bien que nos recherches n’apportent aucun soutien aux avantages environnementaux ou économiques supposés de l’utilisation d’insectes dans l’alimentation animale, il est possible que leur utilisation comme aliment destiné à la consommation humaine directe (c’est-à-dire comme substitut possible aux produits à base de poisson et de viande) constitue une solution durable aux problèmes actuels et futurs. Nous recommandons donc aux recherches futures de se concentrer sur les techniques permettant d'exploiter les insectes comme nourriture.Doctorat en Sciences
There are a few details that I could not specify in the available input fields. I would like to ask you kindly to add the following information: (1) Prof. Erik Mathijs (KUL) is my second co-supervisor; (2) Next to the Jury members listed, there are Prof. Matthias Finkbeiner (TU Berlin) and Prof. Theo Niewold (KU Leuven), which I could not enter manually.
info:eu-repo/semantics/nonPublished
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De, Bruyn Colin. "Modalités fonctionnelles et évolutives des parasitoses développées par les crabes Pinnotheridae aux dépens des échinides fouisseurs." Phd thesis, Université de Bourgogne, 2010. http://tel.archives-ouvertes.fr/tel-00659457.
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Ce travail s'est intéressé aux liens existant entre la stratégie d'exploitation développée par un crustacé ectoparasite et son comportement reproductif. Le crabe Pinnotheridae Dissodactylus primitivus exploite deux espèces Spatangidae vivant dans la Mer des Caraïbes, Meoma ventricosa et Plagiobrissus grandis. Des approches comportementales, démographiques et génétiques ont été adoptées afin de mettre en lumière le fonctionnement et la biologie de cette symbiose. Par son comportement alimentaire, le crabe occasionne des lésions tégumentaires sur ses hôtes. Celles-ci affectent la fitness de M. ventricosa, au travers de son développement gonadique. Dissodactylus primitivus exploite ses deux espèces hôtes de façon asymétrique. La reproduction des parasites se déroule sur les deux hôtes, alors que le recrutement ne s'effectue que sur M. ventricosa. Ce cycle vital asymétrique du crabe serait stabilisé par la qualité et la rareté de P. grandis. En outre, Le comportement sexuel du crabe sur M. ventricosa répondrait aux critères de la polygynandrie à femelles mobiles. Selon ce modèle, les mâles et les femelles se déplacent entre les hôtes à la recherche de partenaires multiples. Lors de ces déplacements, le crabe s'aiderait de son aptitude à localiser chimiquement ses hôtes. Néanmoins, ce mécanisme s'avère plastique et pourrait refléter l'asymétrie du cycle vital. En effet, cette différence n'a pas d'origine génétique, car les crabes vivant au sein du site d'étude constituent la même population quelle que soit l'espèce hôte considérée. Les marqueurs moléculaires microsatellites mis au point dans ce travail permettront lors de futurs travaux d'affiner les observations sur les modalités d'accouplement du crabe et d'estimer sa capacité de dispersion.
Books on the topic "Animals life cycles"
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Ferrari, Marco. Life cycles. Raintree Steck-Vaughn, 1999.
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Rau, Dana Meachen. Animals =: Los animales. Marshall Cavendish Benchmark, 2010.
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Rau, Dana Meachen. Animals. Marshall Cavendish Benchmark, 2009.
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Morgan, Sally. Animals. Franklin Watts, 2012.
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Barbara, Taylor. Slimy spawn and other gruesome life cycles. Crabtree Publishing Company, 2015.
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Day, Trevor. Pets parents hate!: Animal life cycles. Capstone Press, 2009.
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Day, Trevor. Pets parents hate!: Animal life cycles. Capstone Press, 2009.
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Dixon, Richard C. Illustrated life cycles of common parasites in animals. R.C. Dixon, 1987.
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How do animals change? Crabtree Pub., 2011.
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Steve, Parker. Seal: Habitats, life cycles, food chains, threats. Raintree, 2004.
Book chapters on the topic "Animals life cycles"
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Pandian, T. J. "Direct and Indirect Life Cycles." In Evolution and Speciation in Animals. CRC Press, 2021. http://dx.doi.org/10.1201/9781003176381-24.
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Sutton, Julian. "Reproduction in Animal Life Cycles." In Biology. Macmillan Education UK, 1998. http://dx.doi.org/10.1007/978-1-349-15201-8_13.
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Régnière, Jacques, and Jesse A. Logan. "Animal Life Cycle Models." In Phenology: An Integrative Environmental Science. Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-007-0632-3_15.
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Régnière, Jacques, and James A. Powell. "Animal Life Cycle Models (Poikilotherms)." In Phenology: An Integrative Environmental Science. Springer Netherlands, 2013. http://dx.doi.org/10.1007/978-94-007-6925-0_16.
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Bruun, Sander, Marieke T. Hoeve, and Morten Birkved. "Life Cycle Assessment of Manure Management Systems." In Animal Manure Recycling. John Wiley & Sons, Ltd, 2013. http://dx.doi.org/10.1002/9781118676677.ch16.
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Cays, John. "The Energy Essential: Physical Forces Animate All Things." In An Environmental Life Cycle Approach to Design. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-63802-3_2.
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van Middelaar, C. E., H. H. E. van Zanten, and I. J. M. de Boer. "14: Future of animal nutrition: the role of life cycle assessment." In Poultry and pig nutrition. Wageningen Academic Publishers, 2019. http://dx.doi.org/10.3920/978-90-8686-884-1_14.
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Silvenius, F., N. Koskinen, S. Kurppa, T. Rekilä, J. Sepponen, and H. Hyvärinen. "Life cycle assessment of mink and fox pelts produced in Finland." In Proceedings of the Xth International Scientific Congress in fur animal production. Wageningen Academic Publishers, 2012. http://dx.doi.org/10.3920/978-90-8686-760-8_15.
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Oonincx, Dennis G. A. B. "Environmental impact of insect rearing." In Insects as animal feed: novel ingredients for use in pet, aquaculture and livestock diets. CABI, 2021. http://dx.doi.org/10.1079/9781789245929.0007.
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Abstract This chapter discusses the environmental impact of insect rearing. Direct greenhouse gas (GHG) emissions from insects used as feed or food are discussed and data from life cycle assessments (LCAs) on commercially farmed insects are discussed per species. The relevance of the utilized feed on the environmental impact of insects and their derived products, including suggestions to lower this impact are also discussed. It is concluded that land use associated with insect production generally seems low, compared to conventional feed and food products. The EU (expressed as fossil fuel depletion) of insect production is often high compared to conventional products. To a large extent this is because several LCAs have been conducted for systems in temperate climates, which require extensive climate control.
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Heleno, Ruben H. "The effect of non-native plant invasions on the dispersal of native seeds." In Plant invasions: the role of biotic interactions. CABI, 2020. http://dx.doi.org/10.1079/9781789242171.0256.
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Abstract Non-native plants change the communities they integrate in multiple ways, including direct and indirect effects on co-occurring native vegetation. While direct effects are more obvious, indirect effects, i.e. those mediated by biotic interactions with other trophic levels, can also have pervasive consequences for long-term community persistence. Seed dispersal is a critical stage during the life cycle of most plants, as it lays the foundations for plant recruitment patterns and long-term vegetation dynamics. By interacting with seed-dispersing animals, primarily frugivorous birds and mammals, plants can positively or negatively affect the dispersal of co-occurring native seeds. In an increasingly invaded world, it is thus critically important to identify general trends on the direction and magnitude of these effects. This chapter reviews the empirical evidence supporting such changes and the potential underlying mechanisms driving them. While the direct impacts of plant invasions are relatively easy to document, indirect effects are much harder to detect. Nevertheless, the most important consequence of the incorporation of new fruiting plants into native communities seems to be a direct competition for the services provided by the local dispersers, negatively affecting native seed dispersal rates. However, another key message emerging from the literature is that responses are highly idiosyncratic, and usually habitat- and species-specific, and therefore resistant to broad generalizations. Fruiting phenology, and in particular the synchrony/asynchrony between the availability of native and non-native fruits, seems to be a particularly important driver of the direction of the responses (i.e. towards facilitation or competition). However, most evidence is still derived from anecdotal observations and formal community level assessments are largely missing. Similarly, how invasive plants change the emergent structure of seed dispersal networks remains uncertain, with early evidence suggesting that novel seed dispersal networks might be structurally very similar to native ones. Bringing together classic experimental designs and new technical and analytical tools to provide broad synthesis will be vital in the near future to clarify the direction, magnitude and generality of these effects.
Conference papers on the topic "Animals life cycles"
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Aznar, Francisco Javier, Angeles Raduán, and Mercedes Fernández. "UNDERSTANDING THE LIFE CYCLES OF ANIMALS: A PEDAGOGIC PROPOSAL FOR BIOLOGY STUDENTS." In International Technology, Education and Development Conference. IATED, 2016. http://dx.doi.org/10.21125/inted.2016.1977.
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Shafer, Michael W., and Eric Morgan. "Energy Harvesting for Marine-Wildlife Monitoring." In ASME 2014 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/smasis2014-7630.
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Bio-logging devices are systems mounted to an animal that measure parameters associated with the animal or its environment. These devices date back to the 1930’s in their simplest form, while modern devices use suites of digital sensors, microcontrollers, and wireless data communication. Despite these advances, there has always been a fundamental relationship between power consumption and the amount of science that can be conducted. There are now a number of commercially available devices that use solar cells to supplement their daily energy budget, but supplemental solar power is not useful for species that are nocturnal, subterranean, aquatic, or spend significant time beneath dense forest canopies. As such, there have been calls from the marine biology community for devices that could harvest power from their environments. For these marine species, alternative energy harvesting techniques are required. Here we explore a new application for energy harvesting as a power source for marine wildlife bio-logging tags. Marine animals cover wide swaths of the ocean, making tracking and data collection challenging. Tagging these animals with devices that track their location and/or collect data about the animal or its surroundings require large batteries and have limited life spans due to high power requirements for satellite data relays. With limited solar irradiance at depth making solar power less attractive, we review and explore other forms of energy that could be harvested, such as energy from fluid flow and hydrostatic pressure cycles. We investigate the energy potential from a number of sources and compare these values with the requirements of current bio-logging systems to assess required transduction efficiencies. The application of energy harvesting on animal tags could result in nearly indefinite life systems allowing for data collection from a single animal over the course of many years.
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Sullivan, Adam, Xiaopeng Zhao, and Chunlei Su. "Mathematical Modeling of Within-Host Dynamics of Toxoplasma Gondii." In ASME 2011 Dynamic Systems and Control Conference and Bath/ASME Symposium on Fluid Power and Motion Control. ASMEDC, 2011. http://dx.doi.org/10.1115/dscc2011-6133.
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Toxoplasma gondii is a protozoan capable of replicating sexually in cats and asexually in other warm-blooded animals. By using a three dimensional mesh of both the brain and spleen, it is possible to simulate using a computational model to demonstrate the entire life-cycle within an intermediate host of the parasite as it completes the life-cycle using host cells of these organs. A cellular automata model is developed to demonstrate the dynamics of the parasite, where each cell follows the same set of rules for each discrete time-step. This cellular automata model allows for data simulations to be run of the parasite within a mouse and display graphical images and animations.
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Tang, Zhongping, Peng Jin, Dingwei Sun, Shaoming Zhang, and Weimin Liu. "Investigation of Some Base Oil as Biodegradable Water-Cooling Two-Stroke Engine Oil." In ASME 2006 Internal Combustion Engine Division Spring Technical Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/ices2006-1328.
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According to statistics, a large portion of used lubricants remain as potential hazards for the environment. Particularly, about 30 to 50% lubricant used in outboard marine engines is not burned completely and released into the water. As a result, consumers demand environmentally compatible lubricants due to concern about loss of mineral oil-based lubricants to the environment which can result in water contamination and pose a threat to animal and plant life. To prevent bioaccumulation of these materials in aquatic plants and animals, many agencies are considering regulations toward to biodegradable two-stroke outboard marine engines oil. Vegetable oils and ester oils are very suitable to develop “green lubricants”. Ester oils usually show excellent high temperature stability, low temperature fluidity, high viscosity index, very low volatility, good miscibility and biodegradability, but they are expensive and also produce many poisonous materials to environmental during produce process. Vegetable oils are biodegradable, nontoxic and renewable, moreover, their cost is reasonable compared to ester oils. Accordingly, vegetable oils are considered as potential candidates to replace conventional mineral oil-based lubricating oils, but the poor oxidative stability limits their utilization in large scale. Investigation of this work have found that proper percentage rapeseed oil can meet the requirements of biodegradable water-cooling two stroke engine oil, futhermore this two-cycle engine oil has good miscibility without need any miscibility-enhancing solvents. Research results indicate that two-cycle engine oil, which comprised rapeseed oil, ester oil and low viscosity hydrocracked oil as well as functional additives, exhibits good oxidative stability, easy biodegradability and good miscibility.
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Doby, Troy A., Michael Gonzalez, and MaryAnn Curran. "Life Cycle Assessment (LCA) as a Framework for Addressing the Sustainability of Concentrated Animal Feeding Operations (CAFOs)." In World Environmental and Water Resources Congress 2006. American Society of Civil Engineers, 2006. http://dx.doi.org/10.1061/40856(200)321.
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Gu, Xiang, Daniel Leong, Rashal Mahammud, Yong Hui Li, Hui Bin Sun, and Luis Cardoso. "Continuous Passive Motion and Loading System Design for the Study of Pro- and Anti-Inflamatory Mediators in Articular Cartilage." In ASME 2009 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2009. http://dx.doi.org/10.1115/sbc2009-206753.
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Joint diseases are common causes of disability worldwide. Physical activity and weight bearing conditions play an important role in the regulation of joint homeostasis throughout life. The parametric characterization of deleterious and beneficial joint loading regimens influencing the homeostasis of articular cartilage is of great interest from both a basic research and clinical practice point of view. The development of in vivo animal models is critical to investigate the underlying mechanisms mediating the biological response of articular joints to external mechanical stimuli. For this purpose, the design of a device capable of accurately control the joint motion and loading in a small animal is needed. In the present work, an assisted motion system was conceived to perform continuous passive motion (CPM) and continuous loaded motion (CLM) on the knee joint of a small animal in vivo. A major purpose of this system is the study of the inflammatory and anti-inflammatory response of cartilage under several biomechanical environments. Therefore, a key design criterion was to avoid any invasive intervention (i.e. intraskeletal fixators) that may produce an intrinsic inflammatory response and then obscure/mislead the assessment of the biological markers of interest. Other important design criteria include real time control of the knee joint position, angular displacement, cyclic motion frequency and custom load magnitude applied in the axial direction along the tibia.
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Adi, Gayatri, Carrie Hall, David Snyder, et al. "An Experimental and Simulation Study of Increases in Fuel Consumption and NOX Emissions in a Biofueled Diesel Engine." In ASME 2009 Internal Combustion Engine Division Spring Technical Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/ices2009-76104.
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Alternative fuel vehicles are gaining importance as a means of reducing petroleum dependence. One attractive option is biodiesel, a renewable diesel fuel produced from plant or animal fats, since it significantly reduces carbon monoxide, unburned hydrocarbon, and particulate matter emissions as well as carbon dioxide when considered on a full life cycle basis. However, biodiesel combustion also typically results in increased fuel consumption and nitrogen oxide (NOx) emissions relative to petroleum diesel. In order to determine the cause of and develop mitigation strategies for increased biodiesel fuel consumption and NOx emissions, an accurate simulation model was developed and validated. Key fuel properties as well as ignition delay characteristics were implemented in a previously validated whole engine model to reflect soy-biodiesel fuel. The model predictions were within 5% of experimental results for most values at the three operating points. Using this biodiesel model, the “biodiesel NOx effect” was linked to the near stoichiometric equivalence ratios for biodiesel.
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Fernandez, Rajan, and Keith Alexander. "An Experimental Investigation Assessing the Validity of Quasi-Static Calculations for an Oscillating Hydrofoil." In ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2011. http://dx.doi.org/10.1115/omae2011-49440.
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Inspired by animals, flapping wing propulsion has been of interest since the early 1900s. Flapping hydrofoil propulsion has been attempted by designers of human powered watercraft because of the novelty and the apparent high theoretical efficiency, but with limited success. The earliest human powered hydrofoil, the Wasserlaufer, was invented by Julius Schuck in 1953. The first really successful human powered hydrofoil, the Trampofoil, was invented by Alexander Sahlin in 1998. While these craft function adequately the design data for flapping hydrofoils is inadequate or not available. This paper describes an experimental program and initial results for the required data. To design a vehicle with a lifting and thrusting oscillating hydrofoil the force that the hydrofoil will exert on the vehicle through its entire oscillating cycle must ideally be known. The force profiles could be estimated via quasi-static calculations based on steady flow lift and drag coefficients, but these often do not cover the full 360 degree range that can be required and there is doubt that the steady flow coefficients properly represent the dynamic situation of an oscillating hydrofoil. Hence a valuable process would be one that could determine dynamic drag and lift coefficient loops as function of the Strouhal number, heaving and pitching profiles. To work toward the collection of this information, experimental data is being recorded in a towing tank with an oscillating NACA4415 hydrofoil over a range of Strouhal numbers and types of oscillating profiles. While there are still some limitations to the experimental equipment preliminary experimental results show the limitations of using quasi-static calculations and go some way to providing the design data for the hydrofoil section tested. We conclude that quasi-static calculations based on the gliding coefficient curve for for an oscillating hydrofoil are only valid for very small Strouhal numbers (St≪0.05). We have shown that as the Strouhal number increases, the error in such calculations increases very rapidly. We also note that the lift coefficient of the hydrofoil has a strong dependence on the angle of attack and is not affected by the gliding stall.
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Glaude, Pierre A., Rene´ Fournet, Roda Bounaceur, and Michel Moliere. "Gas Turbines and Biodiesel: A Clarification of the Relative NOX Indices of FAME, Gasoil, and Natural Gas." In ASME Turbo Expo 2009: Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-59623.
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There is currently a sustained interest in biofuels as they represent a potential alternative to petroleum derived fuels. Biofuels are likely to help decrease greenhouse gases emissions and the dependence on oil resources. Biodiesels are Fatty Acid Methyl Esters (FAMEs) that are mainly derived from vegetable oils; their compositions depend from the parent vegetables: rapeseed (“RME”), soybean (“SME”), sunflower, palm etc. A fraction of biodiesel has also an animal origin (“tallow”). A key factor for the use of biofuels in gas turbines is their Emissions Indices (NOx, CO, VOC, PM) in comparison with those of conventional “petroleum gasoils”. While biodiesels reduce carbon-containing pollutants, experimental data from diesel engines show a slight increase in NOx. The literature relating to gas turbines is very scarce. Two recent, independent field tests carried out in Europe (RME) and in the USA (SME) showed slightly lower NOx while a lab test on a microturbine showed the opposite effect. To clarify the NOx index of biodiesels in gas turbines, a study has been undertaken, taking gasoil and natural gas (NG) as reference fuels. In this study, a calculation of the flame temperature developed by the 3 classes of fuels has been performed and the effect of their respective compositions has been investigated. The five FAMEs studied were RME, SME and methyl esters of sunflower, palm and tallow; these are representative of most widespread vegetable and animal oil bases worldwide. The software THERGAS has been used to calculate the enthalpy and free energy properties of the fuels and GASEQ for the flame temperature (Tf), acknowledging the fact that “thermal NOx” represents the predominant form of NOx in gas turbines. To complete the approach to structural effects, we have modeled two NG compositions (rich and weak gas) and three types of gasoil using variable blends of eleven linear/branched/cyclic molecules. The results are consistent with the two recent field tests and show that the FAMEs lie close to petroleum gasoils and higher than NG in terms of NOx emission. The composition of the biodiesel and regular diesel fuel influences their combustion heat: methyl esters with double bonds see a slight increase of their Tf and their NOx index while that of gasoil is sensitive to the aromatic content.
Reports on the topic "Animals life cycles"
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Innovative Solutions to Human-Wildlife Conflicts: National Wildlife Research Center Accomplishments, 2014. U.S. Department of Agriculture, Animal and Plant Health Inspection Service, 2015. http://dx.doi.org/10.32747/2015.7206799.aphis.
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The National Wildlife Research Center (NWRC) is the research arm of Wildlife Services (WS), a program within the U.S. Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS). NWRC’s researchers are dedicated to finding biologically sound, practical, and effective solutions to resolving wildlife damage management issues. They seek these solutions using a multiyear, multidisciplinary project management system. NWRC identifies and prioritizes projects based on feedback from WS program leaders, managers, and stakeholders concerning their most pressing wildlife damage management needs. During 2014, five research projects reached the end of their 5-year life cycle. At the final project reviews, project leaders and their staff presented and discussed each project’s accomplishments, challenges, and findings.