Global ETD Search

161	Chip-Calorimetric Monitoring and Biothermodynamic Analysis of Biofilm Growth and Interactions with Chemical and Biological Agents Mariana, Frida 21 July 2015 (has links) Over the last years, varieties of technologies for biofilm analysis were developed and established. They work on different principles and deliver information about biofilms on different information levels. In this work, chip-calorimetry was applied as an analytical tool that measures heat produced from biofilms. Any change of metabolism in biofilms is reflected by a changed heat flow. The heat, which is the integral of the heat flow vs. time, is quantitatively related to the growth stoichiometry of the biofilm, as described by the Hess’ Law. The heat flow is related to the growth kinetics with the reaction heat as proportionality factor. The results from the calorimetric measurement thus, deliver general information about growth stoichiometry and kinetics. The other interpretation of calorimetric results bases on the assumed proportionality between heat flow and oxygen consumption rate (- 460 kJ/mol ). This ratio is called oxycaloric equivalent. Because in case of aerobic growth the majority of oxygen is consumed in catabolic processes during the electron transport phosphorylation, calorimetry is assumed to provide information about the catabolic side of the metabolism. The newly developed chip-calorimeter applied in this work is much more suitable for biofilm studies compared to conventional microcalorimeters due to the flow-through design of the calorimetric chamber. The measurement of undisturbed growing biofilms and the comparison with conventional biofilm analysis tools (i.e. plate counts, confocal laser scanning microscopy (CLSM), and the determination of intermediates’ concentrations (e.g. ATP)) demonstrate the proper functionality of the calorimetric method and the related cultivation procedure by delivering measurement results in the range of literature values. However, when the biofilms were challenged with antimicrobial agents i.e. antibiotics, bacteriophage, and predatory bacteria, the calorimetric results surprisingly deviated from the reference analyses. By combining the results of the calorimetric and reference analyses, additional information about the antimicrobial effects on biofilms can be acquired. Combination of heat measurement and plate counts, which is one of the most conventional approaches, demonstrated that antimicrobials (especially the bactericidal acting kanamycin) could cause the loss of culturability while the cells were still metabolically active. The measurement of ATP content resulted in values out of the typical range, which indicated that antimicrobial treatments disturbed the cellular ATP regulation and the ATP concentration was no longer linearly correlated to the cell number. ATP measurements are therefore not suitable for antimicrobial susceptibility testing. The comparison of heat profiles with the biovolume determined by quantification of microscopic images shows an elevated cell specific heat production rate after the introduction of some antimicrobials (antibiotics and bacteriophage). In case of antibiotics, this can be explained as a consequence of the bacterial defense mechanisms. Most of the described defense mechanisms against antibiotics need biological energy and therefore drive the electron transport phosphorylation (ETP). In case of biofilm treatments with bacteriophage, the trigger of increasing ETP might be the synthesis of phage proteins, hull material, and genetic information molecules. In aerobic conditions, oxygen is used as terminal electron acceptor. Elevated ETP leads therefore to an increase in oxygen consumption, which correlates to the heat production using oxycaloric equivalent as a factor. These correlations explain the increase of cell specific heat productions as biofilms were challenged by antibiotics and bacteriophage. However, also a decrease of specific heat production was observed (in case of predatory bacteria). Here, the predatory bacteria activity caused various damages in host cells, including the interruption of ETP. With these experiments, chip-calorimetry was demonstrated as a promising complementary tool in biofilm research, which provides deeper insights about metabolic activity and alterations. It benefits from the noninvasive handling and the online, real-time measurement that allow the method to be applied for monitoring purposes. Furthermore, its miniaturized dimension allows easy integration in more complex analytic systems and also reduces experiment costs with minimal media/chemical consumption. This thesis also demonstrates the potential development of chip-calorimetry to be more suitable for routine analyses. The use of superparamagnetic beads as matrix to grow biofilms allows regulated transfer of biofilm samples into and from the measurement chamber. This was an initial step towards automation and higher-throughput analysis. One further outcome of the thesis is based on the highly interesting fact about the elevated heat production rate of the host cells induced by the phage infection observed in the chip- calorimetric experiments. The volume specific detection limit of the chip-calorimeter is lower compared to a commercial microcalorimeter. Thus, the infection effect of phages was additionally measured in microcalorimeter to get better quantitative information about the thermal effect of the infection. The results showed that the immediate heat increase after the addition of phage into the solution of the host cells appeared to be quantitatively related to the infection factor, MOI (Multiplicity of Infection). Unfortunately, microcalorimetric measurements in closed ampoules are often subjected to the oxygen limitation. Thus, this problem of microcalorimetric measurement has been addressed. The combination of experimental results and mathematical modeling showed that the rate of metabolism in the static ampoules is defined by the diffusion rate of oxygen into media. This factor has to be considered while designing biological experiments in closed calorimetric measuring chambers and interpreting the calorimetric results for their biological meaning. Some possible solutions to overcome the oxygen bioavailability problem are e.g. to design the experiments with low biomass, or by using media with elevated density to float the biomass at the interface to air and thus to reduce the diffusion path. info:eu-repo/classification/ddc/620 ddc:620
162	Pivovar ve městě, město v pivovaru - architektonicko urbanistická studie přestavby znojemského pivovaru / Brewery in the city, the city in the brewery - architectural and urban redevelopment of a brewery in Znojmo Balážová, Zuzana January 2012 (has links) Brewery premises waiting for its time once again to raise their fate. The proposal deals with thinning adequate space for the return of the former grandeur of the castle courtyard. Take the power of its current and cumbersome, and bring back into the historic character of the former in the form of vertical predatory towers and all the socio-eco-logical aspects.
163	Action antidumping et droit de la concurrence dans l’Union européenne / Anti-Dumping action and competition law in the european union Reymond, Damien 08 July 2014 (has links) Le droit de l’Union européenne appréhende les comportements d’entreprises en matière de prix par des règles antitrust et par une législation contre le dumping. Ces deux réglementations diffèrent à de nombreux égards. Elles poursuivent des objectifs différents : défense des intérêts de certains concurrents européens versus promotion de la libre concurrence au bénéfice des consommateurs. Cependant, toutes deux contribuent à protéger la loyauté de la concurrence (i.e. promotion d’une certaine homogéniété des conditions de concurrence). Elles appréhendent des pratiques tarifaires différentes : les marchés concernés sont définis différemment (produit concerné exporté depuis un pays tiers et produit similaire fabriqué par l’industrie de l’Union versus marché de produit et marché géographique en cause) et les caractéristiques des entreprises concernées sont également différentes (aucune forme d’accord entre entreprises ou de pouvoir de marché minimum requis par la législation antidumping) ; le dumping discriminatoire n’équivaut à aucun prix discriminatoire anticoncurrentiel, et le dumping à perte n’est pas l’équivalent du prix prédateur ni de tout autre prix bas anticoncurrentiel. Nonobstant leurs différences, les deux réglementations doivent coexister paisiblement. Pourtant, les opportunités de biais protectionnistes dans la détermination du dumping préjudiciable sont toujours nombreuses dans la législation antidumping et la pratique de la Commission. En outre, la mise en oeuvre de la législation antidumping peut être néfaste pour la concurrence dans le marché intérieur via l’incidence des procédures et des mesures antidumping et les effets anticoncurrentiels de certains comportements d’entreprises dans le cadre des procédures antidumping ou environnant ces dernières. De telles incidences nocives pour la concurrence sont déjà réduites par des dispositions telles que la règle du droit moindre et la clause d’intérêt public (intérêt de l’Union), mais pourraient et devraient l’être davantage. / European Union law addresses pricing practices of undertakings through antitrust provisions and an anti-dumping legislation. These two sets of regulations differ in many respects. They pursue different aims: protection of the interest of some European competitors versus promotion of free competition for the benefit o f consumers. However, they both hept to ensure fair competition (i.e. promotion of alevel playing field). They address different pricing practices: the markets concerned are differently defined (concerned product exported from one third country andsimilar product produced by the Union industry versus relevant product and geographic markets) and the characteristics of the undertakings concerned are also different (no sort of agreement between undertakings and no minimum market power required in anti-dumping law); price discrimination dumping in not equivalent to any anti-competitive price discrimination and below cost dumping is not equivalent to predatory pricing or to any other low anti-competitive price. Not with standing their differences, both sets of regulations have to coexist peacefully. Yet, opportunities of protectionist biases in the determination of injurious dumping are still numerous in the anti-dumping legislation and Commission’s practice. Moreover, the enforcementof the anti-dumping legislation may negatively affect competition in the internal market through the impact of the anti-dumping proceedings and measures and the anti-competitive effects of some undertakings’ behaviors within the ambit of, or surrounding the anti-dumping proceedings. Such harmful effects on competition of the anti-dumping action are already reduced by provisions such as the lesser duty rule and the public interest clause (Union interest), but could and should be further reduced. Union européenne Action antidumping Droit de la concurrence Dumping discriminatoire/à perte Prix discriminatoire/prédateurs Intérêt de l'Union Biais protectionnistes Dumping -- Droit européen European Union Anti-dumping action Competition law Price discrimination /delow cost dumping Discriminatory/predatory pricing Union interest Protectionist biases 340
164	An assessment of community understanding of the Human Animal Conservancy Self-Insurance Scheme and the impact of human-wildlife conflicts : a case study from the Kwandu conservancy, north-east Namibia. Kasaona, Marthin Kaukaha. January 2006 (has links) The research problem of this mini-dissertation involves the conflicts between human and wildlife populations and the trialing of ‘compensation’ payouts that are emerging as a critical test within the conservancy. Crop raiders such as elephants, buffaloes, hippopotamus, bush pigs and small rodents, diminish farmers’ resource bases and cash crops, while carnivores are responsible for livestock losses. The aim of the research is to assess the level of community understanding of the compensation scheme and the impact of human wildlife interaction within the conservancy. This mini-dissertation investigated the level of community understanding about the Human Animal Conservancy Self-Insurance Scheme (HACSIS), and the impact of human-wildlife conflicts within the Kwandu Conservancy. Some of the research data were obtained from the conservancy game guards’ event book system, and the actual field research data were collected from the 1st August to 20th August 2006. The researcher conducted a total of 35 interviews, whereby 32 involved face-to-face interviews with single individuals, and 3 separate focus group discussions that consisted of four, five and two conservancy members. The interviews averaged 30 minutes in length. Each interview was preceded by a careful explanation of the purposes of the work, stressing that the intent was to evaluate their understanding and perceptions on HACSIS, the impact of human-wildlife conflicts and to explore better management strategies. The researcher has taken into account that the communities might exaggerate the wildlife problem based on his previous experience with the adjacent conservancy, in the hopes of gaining more compensation – they also use the researcher as a way to vent their frustration at the problem. On the assumption that there may be an element of exaggeration verification of these was obtained from the Event Book System (a manual book used by the Community Game Guards for recording both crops and livestock incidents on daily basis). This mini-dissertation reveals that 74.3 % (n = 26) of respondents are aware of the existence of the HACSIS program and its role, while 17.1 % of respondents had no idea about the scheme’s presence and its involvement to minimize the impact felt by communities when they lose livestock to predators. The percentage of respondents who claimed that they had heard of the scheme’s existence but had no knowledge of its role was 8.6 %. In addition, most respondents (n = 15) claimed that the conservancy committee did not explain to them why their claim forms were rejected. In contrast, some respondents (n = 6) did received feedback on rejected claim forms. HACSIS was not formed to compensate livestock losses based on market value, nor was it intended as a ‘compensation’ scheme. Its aim was to test a conservancy-run process – local verification of claims and monitoring by conservancy committee and traditional authority. In addition, the authorization of payments for a type of ‘self-insurance’ is drawn from conservancy income to partially offset the losses of conservancy members versus the overall gains that wildlife brings to the conservancy (direct conservancy income and local jobs through tourism, trophy hunting, own use game harvesting). Conservancy committees and the support NGO, IRDNC, agreed on the amount to be refunded for animal losses before the scheme was started, initially using donor funding in the trial phases. The amount was deliberately kept low as it was acknowledged from the start that conservancies themselves would take over the repayments from their own income. Once the conservancy was used to its own income to finance the scheme, conservancy members could vote to increase amounts paid for predator losses. The crucial aspect, according to IRDNC, was that the process itself be tested and that the scheme be run by the conservancy, with Ministry of Environment and Tourism and IRDNC merely monitoring and providing assistance as needed. Compensation is based on this pre-determined amount that is less than the livestock value. However, the research reveals that respondents (n = 19) were dissatisfied with the amount paid (N$ 800-00 per ox killed), because they claim that the amount paid to relieve the immediate impact from wildlife is too little to sustain the affected member. In contrast, some respondents (n = 8) were satisfied with the amount paid as compensation. Despite criticisms about the amount paid for livestock losses, none of the respondents (n = 22) who were familiar with the scheme wanted it to be abolished. The respondents emphasized the need for the conservancy committee to review the amount paid as compensation, especially for cattle. They suggested an increase from the current N$ 800-00 to N$ 1000-00 per ox loss. The research reveals that community livestock management practices have not changed to deliberately benefit from the compensation. In fact community management strategies have improved because of the condition set by the review committee dealing with the compensation scheme. Wildlife incidents have increased because animals are habituated to techniques used by communities to deter them and this has contributed to high livestock incidents. For human-wildlife conflicts, the research acknowledges that the conflict exists. Between 2003-2005, the Kwandu Conservancy reported 1508 incidents of damage to crops by wildlife. Species that were responsible included elephants with 30.2 % damage, bush pigs (29.8 %), hippopotamus (12.7%), antelopes (12.7 %), porcupine (7.5 %), and baboons/monkeys (7.2 %). Most of the crops destroyed by crop raiders, as suggested by the respondents, were maize (30 %), sorghum (26 %), millet (17 %), groundnuts (14 %), pumpkins (8 %) and beans (5%). During the same period of crop losses, the conservancy reported 98 livestock incidents. Animals responsible for livestock incidents were crocodile with 32 incidents (32.7 %), then hyena (23 incidents, 23.5 %), leopard (22 incidents, 22.4 %) and lion (21 incidents, 21.4%). The role of community game guards was found to be extensive. From a total 35 responses, 74.3 % (n = 26) of members stated that community game guards effectively record incidents, chased problem-causing animals from the community crop fields by shouting or shooting in the air, and assessed or verified killed livestock for compensation purposes. In addition, community game guards conduct crop assessment for record-keeping purposes. The scheme for crop compensation is to be introduced in 2007. Currently there is no proper formula to use in assessing the value of crops and the method to use to compensate the affected members. Other methods used by communities to deter wildlife include sleeping in the field to guard crops, cracking a whip, construction of human statues, hanging tins on the fence, chilli coils, watchtowers and digging trenches. Respondents had different views on the best management practices for problem-causing animals. The response was generally based on the degree of threat that the animal posed. Most (43.8 %, n = 14) preferred the monitoring of problem-causing animals that are sighted in an area as a best practice, while 40.6 % (n = 13) of respondents preferred the animal to be captured and relocated to parks. Only 25.6 % (n = 5) of respondents preferred that the animal be destroyed. The management practices preferred by respondents when an animal kills a person are different from when an animal is simply sighted in the area. If an animal kills a person, only 12.5 % (n = 4) of respondents preferred that the animal be captured and relocated to parks, while 87.5 % (n = 28) of respondents preferred the problem-causing animal to be destroyed. None of the respondents suggested monitoring as the best management option for this degree of threat. In conclusion, the research revealed that Human Animal Conservancy Self Insurance Scheme does not treat the cause of the problem but the symptom. This approach does not decrease the level of the problem given that the cause of the problem is not addressed. Therefore, the researcher stressed the need to fully explore and implement the recent piloted lion, crocodile fencing, and elephant proof fencing and elephants chilli coil to address and reduce the problem within Kwandu Conservancy. In addition, the research revealed that the scheme has very lengthy delays before compensation is paid and the review panel does not arrange meetings on the stipulated dates. This causes a back-log in the number of claims that need to be reviewed and approved. On Human Wildlife Conflict the research findings recommend the need to strengthen and improve existing problem-causing animal management strategies that are in place. Innovative strategies include reducing the number of stray livestock at night and developing static fences. Communities should be advised, as is being done by IRDNC, to herd their livestock during the day and to build strong kraals. This is the most effective and cheapest way to prevent livestock from being taken by predators at night. Further more the research revealed that the combination and rotation of the methods yield high success rather than deploying a single method over a long period, for the prevention of crop losses methods include guarding the crop field, cracking a whip, shooting in the air, watchtowers, human statues and beating drums. / Thesis (M.Env.Dev.)-University of KwaZulu-Natal, Pietermaritzburg, 2006. Livestock--Losses--Namibia. Livestock--Losses--Economic aspects. Predatory animals--Control--Namibia. Wildlife pests--Control--Namibia. Crop losses--Namibia. Crop losses--Namibia. Wildlife conservation--Namibia. Human-animal relationships--Namibia. Theses--Environmental science.
165	Nanocontamination d'organismes aquatiques par des particules inorganiques : transfert trophique et impacts toxiques / Nano-contamination of aquatic organisms by inorganic particles : trophic transfers and toxic impacts Perrier, Fanny 21 December 2017 (has links) En raison d’une utilisation croissante et massive, les nanoparticules manufacturées apparaissentcomme de potentiels contaminants émergents pour l’environnement, incluant notammentles écosystèmes aquatiques. Alors que le transfert trophique semble constituer unevoie d’exposition majeure pour les organismes, une connaissance lacunaire dans la littératurescientifique persiste, résultant pour partie des difficultés expérimentales inhérentes àce type d’exposition. Pour ce travail en conditions contrôlées de laboratoire, les nanoparticulesd’or (sphériques, 10 nm, fonctionnalisées aux PEG-amines), stables en solution, ontété choisies pour l’étude du transfert trophique et des impacts toxiques sur des organismesaquatiques. Ce continuum trophique considère la base des réseaux trophiques (biofilms naturels,algues), des niveaux intermédiaires (poissons brouteurs, bivalves suspensivores), jusqu’auxorganismes de haut de chaînes trophiques, avec l’anguille européenne. Avec des expositionsréalisées à de relatives faibles doses, ce travail tend à la représentativité environnementale.Des approches méthodologiques intégratives des niveaux subcellulaire à tissulaire(RT-qPCR, séquençage haut-débit, histologie) ont permis d’évaluer les impacts toxiques.Les résultats indiquent une importante capacité de rétention des nanoparticules par les biofilmsnaturels. À la suite d’une exposition de 21 jours, les dosages d’or révèlent un transfertdes biofilms aux poissons brouteurs, avec une distribution de l’or dans tous les organes. Deplus, ce transfert est associé à une réponse inflammatoire au regard des lésions histologiquesobservés dans les foies, rates et muscles des poissons exposés. Une chaîne alimentaire « naturelle» à trois maillons trophiques, impliquant algues - bivalves - anguilles européennes,atteste d’un transfert significatif jusqu’au poisson prédateur. Enfin, l’analyse du transcriptome,par une approche de séquençage haut-débit, des foies et cerveaux d’anguilles exposéesaux nanoparticules par nourriture enrichie, a permis de mettre en évidence une réponseconjointe à ces deux organes dans des processus biologiques associés au système immunitaireet sa régulation, dont des récepteurs NOD-like impliqués dans l’inflammasome.L’ensemble des résultats expérimentaux interpellent quant aux effets délétères à long-termequ’engendreraient les nanoparticules sur les écosystèmes aquatiques, illustrant par ailleursla propension de ces contaminants à être transférés dans les chaînes trophiques. / Due to an increasing and massive use, engineered nanoparticles are raising as potentialemerging contaminants in the environment, including aquatic ecosystems. While trophictransfer appears to constitute a major exposure route for organisms, scientific literature hasdifficulties to respond to the questions raised to explore the range of the interactions existingbetween nanoparticles and living organisms at different scales from the trophic interactionsto the cellular impacts. This problem is partly due to experimental difficulties inherent tothis exposure type. For this work performed in controlled laboratory conditions, sphericalgold nanoparticles (10 nm, coated with PEG-amines, positively charged) were chosen tostudy the trophic transfer and toxic effects on aquatic organisms. Trophic chains concernedseveral trophic levels (up to three) with a variety of species considered : the basis of thetrophic web with natural biofilms or microalgae, intermediate levels with grazing fish orsuspensivorous bivalves, and up to top food chain organisms, with the European eel, a carnivorousfish.With relatively low doses for exposures, this work tends to represent environmentalconditions. Integrative methodological approaches from subcellular to tissue levels(RT-qPCR, RNA-sequencing, histology) were performed in order to assess toxic impacts.The results indicate a high retention capacity of nanoparticles by natural biofilms. Followinga 21-day exposure, gold quantifications reveal a transfer from biofilms to grazing fish, witha gold distribution in all organs. Moreover, this transfer is associated with an inflammatoryresponse according to the histological lesions observed in the liver, spleen and muscle ofexposed fish. A longer food chain, with three trophic levels involving microalgae - bivalves- European eels, is set up to give a better representation of the complexity of trophic interactionsin the aquatic environment. It shows a significant transfer to the predatory fish.Transcriptomic analyses, using the RNA-sequencing approach, for the liver and the brain ofexposed eels by nanoparticles’ enriched food, highlight a joint response for these two organsin the biological processes associated with the immune system and its regulation, includingNOD-like receptors involved in inflammasome.All the experimental results suggest long-term harmful effects that nanoparticles would generatein aquatic ecosystems, emphasizing the ability of these contaminants to be transferredthroughout trophic chains. Nanoparticules d’or Expositions chroniques Transfert trophique Écosystème aquatique Algues-biofilms naturels Bivalve-poisson brouteur Poisson prédateur Histologie Transcriptomique Séquençage haut-débit Gold nanoparticles Chronic exposure Trophic transfer Aquatic ecosystem Algae - natural biofilms Bivalve - grazer fish Predatory fish Histology Transcriptomic High throughput sequencing
166	An assessment of caracal population density and human-predator conflict in the Winterberg, Eastern Cape, South Africa Smith, Emma Ruth January 2012 (has links) Human-wildlife conflict frequently involves carnivores, mainly because of their large home ranges and dietary requirements. As such, carnivores tend to be the first animals to be lost in human-dominated ecosystems. This is significant because the removal of carnivores can alter the functionality of ecosystems. However, the conservation of carnivores depends as much on the socio-political and socio-economic landscapes as it does on the ecological one. The consolidation of vast, un-fragmented conservation areas in Africa and the world is unlikely. Thus, unravelling the factors (both biological and sociological) responsible for and influencing human-predator conflict is critical for carnivore conservation. The Winterberg district in the Eastern Cape, South Africa has been a sheep (Ovis aries) farming stronghold for nearly 200 years. Consequently, conflict between farmers and predators is commonplace and depredation of livestock by caracals (Caracai caracal) remains a perennial problem. However, the extent of this human-predator conflict (including a reliable assessment of caracal density) has not been quantified. This study used camera trapping to estimate the density of caracals (a nonindividually recognisable species) in the Winterberg and a structured questionnaire to gauge the general attitudes of the farmers of the region. Caracal density was estimated to be 0.20 caracals/km². This estimate equates to a population of approximately 54 caracals across the entire district. Therefore, caracals do not appear to occur at high densities in the Winterberg. However, the survey of the residents of the Winterberg Conservancy revealed that predators were rated as the greatest problem faced by farmers in the area. Although not significant, it also showed that the size of a respondent's property and sheep mortality due to caracals had the greatest probability of affecting attitudes towards predators. The farmers lost less than 10% of their stock to caracal depredation on an annual basis. Therefore, the general perception that predators were the most important factor in stock loss in the area does not appear to be fully supported by my data. The Winterberg is a male-dominated, multigenerational society and it is likely this propagates certain perceptions towards predators which are a reflection of long-held family traditions and beliefs. Such situations can result in reactions which are disproportionate to the actual scale of the problem. However, my study was limited to a sub-set of the landowners in the Winterberg. Thus, more intensive assessments of caracal space use and community attitudes towards predators are recommended. Felis -- South Africa -- Eastern Cape Human-animal relationships Animal populations -- Estimates
167	Effects of prenatal stress on sepia officinalis / Les effets du stress prénatal sur la seiche sepia officinalis O brien, Caitlin 08 December 2017 (has links) Le stress prénatal est un sujet d'intérêt éthologique croissant en raison de ses effets sur la santé humaine et le bien-être des animaux. Cette thése de doctorat s’intéresse à la seiche Sepia officinalis, un modèle pratique dans lequel la progéniture en développement peut être séparée de leurs mères pour examiner diverses sources potentielles de stress en isolement expérimental. Plusieurs catégories de facteurs de stress ont été appliquées aux embryons et aux juvéniles et la progéniture résultante a été testée dans une série d'épreuves physiologiques et comportementales. L'objectif était de déterminer si différents types de stress prénatal affectent la seiche et, dans l'affirmative, comment ces effets se transmettent. Les données présentées démontrent que les stresseurs appliqués aux femelles reproductrices (stress maternel), ainsi que les stresseurs appliqués directement aux embryons (stress embryonnaire), affectent le comportement postnatal (y compris la structuration corporelle, la latéralisation cérébrale, la prédation et les schémas d'activité) la mémoire et / ou la neurobiologie (y compris les concentrations et le renouvellement de la monoamine, la taille des différents lobes cérébraux et la division cellulaire). Les résultats mettent en évidence la présence de trois voies par lesquelles le stress peut exercer des effets: sur le nombre de descendants produits par la femelle, la transmission de la femelle à sa progéniture et directement sur la progéniture elle-même. Les expériences ont également démontré qu'un facteur de stress complètement artificiel (lumière forte) affectait un éventail plus large de comportements chez la progéniture qu’un stress naturel (odeur de prédateur). Enfin, les données ont montré que l'environnement d'incubation et d’élevage peuvent également affecter la progéniture et méritent donc une attention particulière dans la formulation et l'interprétation des expériences avec cette espèce. Ces découvertes informent à la fois les pratiques de bien-être des seiches et d'autres céphalopodes (par exemple, réduisent la manipulation pour maximiser la reproduction) et élucident et renforcent les principes éthologiques qui s'appliquent au stress animal en général (par exemple la transmission des effets de stress de la mère à la progéniture). Compte tenu des informations fournies ici et dans de nombreuses autres études, la seiche et d'autres céphalopodes devraient continuer à servir de modèles comportementaux en éthologie et en biologie en général. / Prenatal stress is a subject of growing ethological interest due to its effects on human health and animal welfare. This Ph.D. thesis utilizes the cuttlefish Sepia officinalis, a convenient model in which developing offspring can be separated from their mothers to examine various potential sources of stress in experimental isolation. Several categories of stressors were applied to cuttlefish and cuttlefish eggs and the resulting offspring were tested in a range of physiological and behavioral tests. The goal was to determine if various types of prenatal stress affect cuttlefish, and if so, how these effects are transmitted. The data presented demonstrate that both stressors applied to reproducing females (maternal stress), as well as stressors applied directly to embryos (embryonic stress), affected post-natal behavior (including body patterning, brain lateralization, predation and activity patterns), learning, memory and/or neurobiology (including monoamine concentrations and turnover, the size of various brain lobes and cell division). The results highlight the presence of three pathways by which stress can exert effects: on the number of offspring produced by the female, transmission from the female to her offspring and directly on the offspring themselves. The experiments also demonstrated that a completely artificial stressor (bright light) affected a wider range of behaviors in offspring than a natural-occurring one (predator odor). Finally, the data showed that incubation and spawning environment can also affect offspring, and thus deserve attention in the formulation and interpretation of experiments with this species. These findings inform both welfare practices for cuttlefish and other cephalopods (e.g. reduce handling to maximize reproduction) as well as elucidating and reinforcing ethological principles that apply to animal stress in general (e.g. the transmission of stress effects from mother to offspring). Given the insight provided here and in numerous other studies, cuttlefish and other cephalopods should continue to serve as behavioral models in ethology and biology in general. Odeur de prédateur Stress maternel Facteur de stress artificiel Structuration du corps Latéralisation cérébrale Activité Réponse à une menace Omportement prédateur Test PIT, Monoamine Volumétrie Marquage phosphohistone Predator odor Maternal stress Artificial stressor Body patterning, Brain lateralization Activity Threat response Predatory behavior, learning PIT test Monoamine Volumetry Phosphohistone labeling
168	Fake Science und was Bibliotheken dagegen tun können Schmidt, Christian 30 March 2020 (has links) »Fake Science« ist eine von vielen Bezeichnungen für gefälschte oder manipulierte Wissenschaft. Wie andere Begriffe, die auf das Attribut »Fake« zurückgreifen, ist auch dieser jüngst von Umdeutungen betroffen. So machte sich die breit inszenierte Medienberichterstattung des Jahres 2018 zu unseriösen Zeitschriftenverlagen den Fake-Science-Begriff für das Phänomen »Predatory Publishing« großzügig zu eigen. Diese rhetorische Aneignung trägt zu sprachlicher Unschärfe bei, lenkt vom Kern des Problems ab und macht den Begriff für seine politische Vereinnahmung anfällig. In Bibliotheken sind die Kompetenzen vorhanden, sowohl gegen die angesprochenen Phänomene im wissenschaftlichen Publikationssystem selbst etwas zu tun als auch solche terminologischen Nebelkerzen zu löschen. / »Fake science« is one of many names for bogus or manipulated science. Like other terms that use the attribute »fake«, it has recently been subject to misinterpretation. For example, the broad media coverage of the year 2018 on dubious journal publishers generously adopted the »fake science« term for the phenomenon known as »predatory publishing«, which is, however, a very different problem. This rhetorical appropriation contributes to terminological imprecision, distracts from the core of the problem and makes the term vulnerable to political usurpation. Academic libraries have the competence not only to do something about the phenomena addressed in the academic publication system itself, but also to remove such terminological smoke candles. info:eu-repo/classification/ddc/020 ddc:020 info:eu-repo/classification/ddc/302.23 ddc:302.23
169	Biodiversity of predatory beetle groups, carabidae and coccinellidae and their role as bioindicators in wheat agroecosystems Makwela, Maria Mammolawa 11 1900 (has links) Predatory Ground beetles (Coleoptera: Carabidae) and Lady beetles (Coleoptera: Coccinellidae) are two of the most diverse groups found in wheat agroecosystems, globally. These groups are important from both an economic and ecological perspective due to their natural services provision. The effect of wheat agroecosystem management on species diversity, abundance, biomass and composition in South Africa is not yet documented, and there is no existing data indicating which predatory carabid and coccinellid species provides essential ecosystem services and bioindicator roles. Therefore, we examined the effects of organic, conventional and intercropped agroecosystems on ground beetle and lady beetle abundance, dried weight (biomass), composition and diversity. Sampling of wheat agroecosystems was conducted in three systems i.e. organic, conventional and organic intercropped. Post-hoc Tukey test indicated a statistically significant difference between species diversity, biomass and abundance in organic and intercropped systems compared to the conventional systems. Regression analysis indicated significant positive correlation between aphid’s density and predatory carabid and coccinellid beetles in the intercropped systems. Amongst the weather factors temperature influenced aphid density and carabid and coccinellid beetles’ abundance. PCA (Principal Component Analysis) revealed significant positive correlation between individual biomass and cropping system. Conventional system showed a negative correlations with carabid and coccinellid individual biomass. We found that some carabid and coccinellid species can be used to measure the quality of agroecosystems. This study provides a fundamental basis for identification and monitoring of carabid and coccinellid species and their role as bioindicators of ecological disturbance. The identified bioindicator species in this study can assist in developing conservation and biomonitoring strategies within agroecosystems. / Agriculture and  Animal Health / M. Sc. (Agriculture) Aphids Biodiversity Bioindicators Biomass Carabid beetles Coccinellid beetles Wheat agroecosystems 632.760968 Predatory insects -- South Africa Aphids -- Host plants -- South Africa Indicators (Biology) -- South Africa Ladybugs -- Research -- South Africa Agricultural ecology -- South Africa Agrobiodiversity -- South Africa
170	Birds, bats and arthropods in tropical agroforestry landscapes: Functional diversity, multitrophic interactions and crop yield Maas, Bea 20 November 2013 (has links) No description available. 630 birds bats arthropods multitrophic interactions agroforestry tropical landscape forest margin landscape functional diversity crop yield exclosure experiments experimental exclusion arthropod suppression avian predation ecosystem services mist netting point counts artificial plasticine caterpillar dummy experiment biological control monitoring mapping Lemon-bellied White-eye Grosbeak Starling Zosterops chloris Scissiostrum dubium Theobroma cacao cacao agroforestry cacao diseases cacao harvest cacao pests flying vertebrates aerial insectivores volant vertebrates logging breeding colony flower herbivory mesopredator release predatory insects ants spiders aphids Lepidoptera Coleoptera Lepidopteran larvae sustainable agriculture sustainable agroforestry management implications management recommendations applied managament extensive land use management landscape management conservation biodiversity-friendly dbh distance to forest forest proximity habitat conversion herbivory Indonesia insectivorous bats insectivorous birds invertebrates Central Sulawesi Napu valley leaf gleaning leaf herbivory pests insects phytophagous insects plant productivity remnant forest trees shade tree managament South-east Asia Paleotropics tropical landscape tree height landscape gradient local shade management Cacao Pod Borer Cherelle Wilt fruit abortion Helopeltis sulawesi deforestation habitat fragmentation land use intensification forest margin species critical decline predation experiment species-specific functions Southeast Asia biodiversity conservation mesopredators food security human welfare human well-being poverty alleviation poverty reduction smallholder cacao smallholder plantation cacao farmers sustainable cacao management landscape perspective landscape scale large scale field experiment long term field experiment human wellbeing economic importance economic value valuation ecosystem services landscape matrix yield quality yield quantity fruit productivity species identity species diversity species richness ecosystem functioning pesticide use chemical compounds complex food web tritrophic interactions wildlife-friendly rural livelihoods endangered bird species endangered bat species endemic endemic birds endemic bats beneficial impact IUCN Lore Lindu National Park bioindicator indicator species forest margin agricultural habitat agroforestry systems population density predation activity species activity cacao flower cacao pod Orthoptera linear mixed effect models Tukey Post Hoc Test AICc model selection generalized least squares restricted maximum likelihood model simplification species richness estimator species accumulation linear mixed-effects models Likelihood Ratio Test Maximum Likelihood nocturnal insects diurnal arthropods nocturnal arthropods diurnal insects landscape context Land- und Forstwirtschaft (PPN621302791)

Search results