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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
281

Have you heard the rumor about the connected consumer? : En kvantitativ studie om digital natives värderingar och förväntningar gentemot företag inom detaljhandeln.

Wikström, Katrin, Szabo Jönsson, Isabell January 2018 (has links)
Syfte: Studien ämnar undersöka skillnader mellan digital natives och digital immigrants i strävan efter att identifiera huruvida de förstnämnda kan anses vara en enskild målgrupp med unika karaktärsdrag. Vidare syftar studien till att kartlägga de två gruppernas värderingar i förhållande till företag inom detaljhandeln med huvudfokus på digital natives. Resultatet förväntas mynna ut i teoretiska och praktiska implikationer om vilka förväntningar digitala konsumenter har på företag inom detaljhandeln. Studien utförs ur ett konsumentperspektiv där konsumenterna undersöks. Frågeställningar: -Hur särskiljer sig digital natives från digital immigrants i värderingar gentemot företag inom detaljhandeln? och -Hur påverkar den digitala disruptionen digital natives förväntningar på företag inom detaljhandeln? Metod: Studien har en deduktiv ansats där en kvantitativ metod använts i form av en enkätundersökning. I undersökningen deltog 206 respondenter vars svar jämfördes mellan digital natives och digital immigrants i databearbetningssystemet SPSS för att hitta likheter och skillnader grupperna emellan. Även en förundersökning av exempelfallet Giraffen har genomförts i syfte att sätta resultatet i relation till verkligheten. Resultat och Slutsats: Studien påvisar att digital natives och digital immigrants skiljer sig åt till viss del, men inte i den utsträckning teorin förklarar. Vidare antyder resultatet att digital natives inte kan ses som en unik målgrupp när de besitter många liknande värderingar som digital immigrants. Därmed kan påstås att förväntningarna på företag är gemensamma för båda grupperna som kan samlas under benämningen digitala konsumenter.
282

Sömnförändringar, sömnpåverkande faktorer samt sömnförbättrande omvårdnadsåtgärder för IVA-patienter : - en litteraturstudie

Björk, Ingela, Leitzig, Andrea January 2010 (has links)
<p><strong>Bakgrund:</strong> Människan tillbringar en tredjedel av sitt liv i sömn det är ett behov vilket hon inte kan vara utan. Patienter som vårdas på IVA drabbas frekvent av sömnstörningar och därmed sömnbrist. Tidigare gjorda studier tyder på att IVA patienter upplever sömnstörningar som ett stort problem.<strong> Syfte:</strong> Att beskriva sömnförändringar, sömnpåverkande faktorer och sömnförbättrande omvårdnadsåtgärder för IVA-patienter.<strong> Metod:</strong> Databassökning gjordes och nyckelord har identifierats. Studier som inkluderar vuxna patienter som vårdats på en IVA har valts för denna beskrivande litteraturstudie.<strong> Resultat:</strong> IVA-patienter drabbas av fragmenterad sömn uppdelad i korta abnorma perioder. Sömnen påverkas av mänsklig intervention, diagnostiska tester samt miljöbetingad ljus och ljud. Minskning av ljud- och ljusnivån samt sammanhängande vilotid utan intervention var de främst undersökta sömnfrämjande omvårdnadsåtgärder i de granskande artiklarna.<strong> Slutsats: </strong>Alla IVA-patienter upplevde störd sömnrytm. I vilken utsträckning sömnrytm stördes berodde på ålder, sjukdom, erfarenhet av IVA-vård och respiratorvård. Omvårdnadsåtgärder som planerad vilotid, sänkningar av ljud och ljus förbättrade sömnmönstret och skapade möjlighet till förbättrad sömn.</p>
283

Environmental pollutants and the reproductive system in birds : Developmental effects of estrogenic compounds

Berg, Cecilia January 2000 (has links)
<p>A number of environmental pollutants have been shown to mimick the action of the female sex hormone estrogen and are, therefore, suspected to be responsible for reproductive abnormalities seen in wildlife. Test systems which can be used in hazard and risk assessment of chemicals with estrogenic effects are consequently needed. In this thesis, I propose the avian egg as an <i>in vivo</i> test system for estrogenic compounds. I conclude that malformation of the left testis and the Müllerian ducts (MDs: embryonic oviducts) in avian embryos can be used as endpoints to examine estrogenic activity of chemicals. MD malformation is more easily determined and thereby faster to use as an endpoint than histologically observed feminization of the testis. The usefulness of MD/oviduct malformations as biomarkers for estrogenic effects in wild birds should be considered. </p><p>The environmental pollutants bisphenol A (BPA) and <i>o,p´</i>-DDT induced similar effects as the synthetic estrogens, ethynylestradiol and diethylstilbestrol. BPA caused MD malformations in quail embryos and ovotestis formation in chicken embryos. <i>o,p´</i>-DDT induced MD malformations in both quail and chicken embryos and ovotestis in chicken embryos. The flame retardant, tetrabromobisphenol A did not induce estrogen-like effects in quail or chicken embryos, but showed a relatively high embryolethality. </p><p>Embryonic exposure to estrogen caused persisting malformations of the oviduct, as well as a changed distribution pattern of the enzyme carbonic anhydrase in the shell gland of adult females. Considering the crucial role of carbonic anhydrase in shell formation, such changes could result in decreased shell quality. I propose that eggshell thinning in avian wildlife could reflect a functional malformation in the shell gland that is induced by xeno-estrogens during embryonic development, rather than being caused by exposure of the adult bird to environmental pollutants. This hypothesis opens new possibilities for studying the mechanisms behind contaminant-induced eggshell thinning in birds.</p>
284

Environmental pollutants and the reproductive system in birds : Developmental effects of estrogenic compounds

Berg, Cecilia January 2000 (has links)
A number of environmental pollutants have been shown to mimick the action of the female sex hormone estrogen and are, therefore, suspected to be responsible for reproductive abnormalities seen in wildlife. Test systems which can be used in hazard and risk assessment of chemicals with estrogenic effects are consequently needed. In this thesis, I propose the avian egg as an in vivo test system for estrogenic compounds. I conclude that malformation of the left testis and the Müllerian ducts (MDs: embryonic oviducts) in avian embryos can be used as endpoints to examine estrogenic activity of chemicals. MD malformation is more easily determined and thereby faster to use as an endpoint than histologically observed feminization of the testis. The usefulness of MD/oviduct malformations as biomarkers for estrogenic effects in wild birds should be considered. The environmental pollutants bisphenol A (BPA) and o,p´-DDT induced similar effects as the synthetic estrogens, ethynylestradiol and diethylstilbestrol. BPA caused MD malformations in quail embryos and ovotestis formation in chicken embryos. o,p´-DDT induced MD malformations in both quail and chicken embryos and ovotestis in chicken embryos. The flame retardant, tetrabromobisphenol A did not induce estrogen-like effects in quail or chicken embryos, but showed a relatively high embryolethality. Embryonic exposure to estrogen caused persisting malformations of the oviduct, as well as a changed distribution pattern of the enzyme carbonic anhydrase in the shell gland of adult females. Considering the crucial role of carbonic anhydrase in shell formation, such changes could result in decreased shell quality. I propose that eggshell thinning in avian wildlife could reflect a functional malformation in the shell gland that is induced by xeno-estrogens during embryonic development, rather than being caused by exposure of the adult bird to environmental pollutants. This hypothesis opens new possibilities for studying the mechanisms behind contaminant-induced eggshell thinning in birds.
285

Effects of Polycyclic Aromatic Hydrocarbons, Metals and Polycyclic Aromatic Hydrocarbon/Metal Mixtures on Rat Corpus Luteal Cells and Placental Cell Line, JEG-3

Nykamp, Julie Ann January 2007 (has links)
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants that can be modified to oxygenated PAH (oxyPAHs) derivatives. It is well known that oxyPAHs tend to be much more reactive than their parent compounds. Toxicity can be attributed to direct interaction with target molecules or generation of reactive oxygen species (ROS). Metals are another class of contaminant found ubiquitously throughout the environment. Some metals are toxic at levels below the 1:1 ratio predicted by the biotic ligand model and are thought to manifest toxicity through ROS generation. Often metals and PAHs occur as co-contaminants in industrialized environments, yet little is known about their potential co-toxicity or mechanisms of action in mammalian reproductive function. Previously, we described that a PAH, 9, 10-phenanthrenequinone (PHEQ), inhibited LH-stimulated progesterone secretion in dispersed rat corpus luteal (CL) cells (Nykamp et al., 2001). Viability was decreased in CL cells exposed to PHEQ and 1,2-dihydroxy-anthraquinone (1,2-dhATQ), but not their parent compounds phenanthrene (PHE) or anthracene (ANT). Similarly, LH-stimulated progesterone production in CL cells was inhibited by PHEQ and 1,2-dhATQ, but not PHE. Further investigation revealed that PHEQ, but not PHE, ANT nor 1,2-dhATQ generated ROS in CL cells. Viability experiments were repeated using the choriocarcinoma cell line JEG-3 with similar results. Various metals were assessed for their toxicity to both CL and JEG-3 cells. The endpoints used to measure viability were metabolic activity and membrane integrity. In general, metabolic activity was a more sensitive indicator of toxicity than membrane integrity. The order of toxicity for metals in CL cells was Hg2+ > Cd2+ > Zn2+ > Ni2+ > Cu2+ for metabolic activity and Hg2+ ≈ Zn2+ > Cd2+ > Cu2+ > Ni2+ for membrane integrity. Only Hg2+ and Cu2+ were tested in JEG-3 cells. While Cu2+ was non-toxic, EC50s for Hg2+ metabolic activity and membrane integrity were 20 mM and 23 mM, respectively. Experiments were designed to study the mixtures of metals and PAHs on viability, ROS production, and LH-stimulated progesterone production in CL cells. Mixtures of each metal with either PHEQ or 1,2-dhATQ were incubated with CL cells and their effect on metabolic activity and membrane integrity assessed. Generally, most metal/oxyPAH mixtures displayed only additive toxicity. However, mixtures of Cu2+ and PHEQ showed synergistic toxicity to both metabolic activity and membrane integrity. Mixture studies in JEG-3 cells used only combinations of Cu2+ or Hg2+ with PHEQ or 1,2-dhATQ. Similar results to metabolic activity and membrane integrity in CL cells were observed. Mixtures of Cu2+ and PHEQ or 1,2-dhATQ were tested in CL cells for their effect on LH-stimulated progesterone secretion and ROS production. Additive effects were observed in both LH-stimulated progesterone secretion and ROS production for Cu2+/1,2-dhATQ mixtures while synergistic effects for both parameters were seen with Cu2+/PHEQ. Efforts to determine the site of action for mixtures of Cu2+/PHEQ involved adding the cholesterol analogue, 22-OH cholesterol (22-OHC) to CL cells in the absence of LH. Cytochrome P450 side-chain cleavage (CYP450scc) enzyme operates constitutively and the addition of 22-OHC to CL cells resulting in a 5-fold increase in progesterone production without added LH. Kinetic assays with 22-OHC show that while progesterone secretion was inhibited with PHEQ addition alone, a further significant reduction with both Cu2+ and PHEQ was not observed. The use of forskolin, an activator of adenylate cyclase, did not show any significant enhancement of progesterone secretion with the addition of Cu2+/PHEQ compared to PHEQ alone. The potential targets of Cu2+/PHEQ mixture include any step in the steroidogenic cascade from activation of protein kinase A onward with the proteins of the mitochondria, cytochrome P450 side chain cleavage enzyme and steroidogenic acute regulatory protein, being the most likely. Differential display polymerase chain reaction (ddPCR) was a molecular approach taken to determine the effect of PHEQ on JEG-3 gene expression. The genes whose expression appeared to be up-regulated with PHEQ exposure were serine protease inhibitor, Alu repeat sequence, heterogeneous ribonuclear ribonucleoprotein C (hnRNP C), eukaryotic translation initiation factor 3 (eIF3), nucleoporin-like protein, eukaryotic translation elongation factor 1a1 (eEF1 a 1), autophagy-linked FYVE domain (Alfy), spectrin, and proteasome. Apparent down-regulated genes in JEG-3 cells after PHEQ exposure included poly(ADP-ribose) polymerase 10 (PARP10), polyglutamine binding protein-1 (PQBP-1), heterogeneous ribonuclear ribonucleoprotein C (hnRNP C), eukaryotic translation initiation factor 5A (eIF5A), and keratin. In both cell types, oxyPAHs were more toxic than their parent compounds. Metals showed greater toxicity to metabolic activity than to membrane integrity. Of the combinations tested, only PHEQ and Cu2+ exhibited synergistic toxicity. ROS generation was the likely mechanism behind PHEQ/Cu2+ toxicity. Both cell types used represent critical roles in human reproductive health. The proper production of progesterone, a critical hormone for the maintenance of pregnancy in mammals, represents a unique endpoint for the assessment of toxicity. These results illustrate the need to study modified oxyPAHs, metals and metal/oxyPAH mixtures for their potential impact on human reproductive health.
286

Effects of Polycyclic Aromatic Hydrocarbons, Metals and Polycyclic Aromatic Hydrocarbon/Metal Mixtures on Rat Corpus Luteal Cells and Placental Cell Line, JEG-3

Nykamp, Julie Ann January 2007 (has links)
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants that can be modified to oxygenated PAH (oxyPAHs) derivatives. It is well known that oxyPAHs tend to be much more reactive than their parent compounds. Toxicity can be attributed to direct interaction with target molecules or generation of reactive oxygen species (ROS). Metals are another class of contaminant found ubiquitously throughout the environment. Some metals are toxic at levels below the 1:1 ratio predicted by the biotic ligand model and are thought to manifest toxicity through ROS generation. Often metals and PAHs occur as co-contaminants in industrialized environments, yet little is known about their potential co-toxicity or mechanisms of action in mammalian reproductive function. Previously, we described that a PAH, 9, 10-phenanthrenequinone (PHEQ), inhibited LH-stimulated progesterone secretion in dispersed rat corpus luteal (CL) cells (Nykamp et al., 2001). Viability was decreased in CL cells exposed to PHEQ and 1,2-dihydroxy-anthraquinone (1,2-dhATQ), but not their parent compounds phenanthrene (PHE) or anthracene (ANT). Similarly, LH-stimulated progesterone production in CL cells was inhibited by PHEQ and 1,2-dhATQ, but not PHE. Further investigation revealed that PHEQ, but not PHE, ANT nor 1,2-dhATQ generated ROS in CL cells. Viability experiments were repeated using the choriocarcinoma cell line JEG-3 with similar results. Various metals were assessed for their toxicity to both CL and JEG-3 cells. The endpoints used to measure viability were metabolic activity and membrane integrity. In general, metabolic activity was a more sensitive indicator of toxicity than membrane integrity. The order of toxicity for metals in CL cells was Hg2+ > Cd2+ > Zn2+ > Ni2+ > Cu2+ for metabolic activity and Hg2+ ≈ Zn2+ > Cd2+ > Cu2+ > Ni2+ for membrane integrity. Only Hg2+ and Cu2+ were tested in JEG-3 cells. While Cu2+ was non-toxic, EC50s for Hg2+ metabolic activity and membrane integrity were 20 mM and 23 mM, respectively. Experiments were designed to study the mixtures of metals and PAHs on viability, ROS production, and LH-stimulated progesterone production in CL cells. Mixtures of each metal with either PHEQ or 1,2-dhATQ were incubated with CL cells and their effect on metabolic activity and membrane integrity assessed. Generally, most metal/oxyPAH mixtures displayed only additive toxicity. However, mixtures of Cu2+ and PHEQ showed synergistic toxicity to both metabolic activity and membrane integrity. Mixture studies in JEG-3 cells used only combinations of Cu2+ or Hg2+ with PHEQ or 1,2-dhATQ. Similar results to metabolic activity and membrane integrity in CL cells were observed. Mixtures of Cu2+ and PHEQ or 1,2-dhATQ were tested in CL cells for their effect on LH-stimulated progesterone secretion and ROS production. Additive effects were observed in both LH-stimulated progesterone secretion and ROS production for Cu2+/1,2-dhATQ mixtures while synergistic effects for both parameters were seen with Cu2+/PHEQ. Efforts to determine the site of action for mixtures of Cu2+/PHEQ involved adding the cholesterol analogue, 22-OH cholesterol (22-OHC) to CL cells in the absence of LH. Cytochrome P450 side-chain cleavage (CYP450scc) enzyme operates constitutively and the addition of 22-OHC to CL cells resulting in a 5-fold increase in progesterone production without added LH. Kinetic assays with 22-OHC show that while progesterone secretion was inhibited with PHEQ addition alone, a further significant reduction with both Cu2+ and PHEQ was not observed. The use of forskolin, an activator of adenylate cyclase, did not show any significant enhancement of progesterone secretion with the addition of Cu2+/PHEQ compared to PHEQ alone. The potential targets of Cu2+/PHEQ mixture include any step in the steroidogenic cascade from activation of protein kinase A onward with the proteins of the mitochondria, cytochrome P450 side chain cleavage enzyme and steroidogenic acute regulatory protein, being the most likely. Differential display polymerase chain reaction (ddPCR) was a molecular approach taken to determine the effect of PHEQ on JEG-3 gene expression. The genes whose expression appeared to be up-regulated with PHEQ exposure were serine protease inhibitor, Alu repeat sequence, heterogeneous ribonuclear ribonucleoprotein C (hnRNP C), eukaryotic translation initiation factor 3 (eIF3), nucleoporin-like protein, eukaryotic translation elongation factor 1a1 (eEF1 a 1), autophagy-linked FYVE domain (Alfy), spectrin, and proteasome. Apparent down-regulated genes in JEG-3 cells after PHEQ exposure included poly(ADP-ribose) polymerase 10 (PARP10), polyglutamine binding protein-1 (PQBP-1), heterogeneous ribonuclear ribonucleoprotein C (hnRNP C), eukaryotic translation initiation factor 5A (eIF5A), and keratin. In both cell types, oxyPAHs were more toxic than their parent compounds. Metals showed greater toxicity to metabolic activity than to membrane integrity. Of the combinations tested, only PHEQ and Cu2+ exhibited synergistic toxicity. ROS generation was the likely mechanism behind PHEQ/Cu2+ toxicity. Both cell types used represent critical roles in human reproductive health. The proper production of progesterone, a critical hormone for the maintenance of pregnancy in mammals, represents a unique endpoint for the assessment of toxicity. These results illustrate the need to study modified oxyPAHs, metals and metal/oxyPAH mixtures for their potential impact on human reproductive health.
287

Sömnförändringar, sömnpåverkande faktorer samt sömnförbättrande omvårdnadsåtgärder för IVA-patienter : - en litteraturstudie

Björk, Ingela, Leitzig, Andrea January 2010 (has links)
Bakgrund: Människan tillbringar en tredjedel av sitt liv i sömn det är ett behov vilket hon inte kan vara utan. Patienter som vårdas på IVA drabbas frekvent av sömnstörningar och därmed sömnbrist. Tidigare gjorda studier tyder på att IVA patienter upplever sömnstörningar som ett stort problem. Syfte: Att beskriva sömnförändringar, sömnpåverkande faktorer och sömnförbättrande omvårdnadsåtgärder för IVA-patienter. Metod: Databassökning gjordes och nyckelord har identifierats. Studier som inkluderar vuxna patienter som vårdats på en IVA har valts för denna beskrivande litteraturstudie. Resultat: IVA-patienter drabbas av fragmenterad sömn uppdelad i korta abnorma perioder. Sömnen påverkas av mänsklig intervention, diagnostiska tester samt miljöbetingad ljus och ljud. Minskning av ljud- och ljusnivån samt sammanhängande vilotid utan intervention var de främst undersökta sömnfrämjande omvårdnadsåtgärder i de granskande artiklarna. Slutsats: Alla IVA-patienter upplevde störd sömnrytm. I vilken utsträckning sömnrytm stördes berodde på ålder, sjukdom, erfarenhet av IVA-vård och respiratorvård. Omvårdnadsåtgärder som planerad vilotid, sänkningar av ljud och ljus förbättrade sömnmönstret och skapade möjlighet till förbättrad sömn.
288

The interaction of environmentally relevant pollutants with nuclear hormone receptors of European flounder (Platichthys flesus)

Colliar, Louise January 2012 (has links)
Nuclear hormone receptors (NHRs) are ligand-activated transcriptions factors which transduce the effects of various hormones as well as nutritional and other environmental signals. They thus function to maintain physiological homeostasis by integrating the tissue expression of specific target genes to regulate a wealth of biological processes including reproduction, development, metabolism and environmental adaptation. Mounting evidence indicates NHRs are the target of endocrine disrupting compounds (EDCs), exogenous chemicals, often of anthropogenic origin, which disrupt NHRs and thus the processes under their control. EDCs can interfere with NHR signalling by activating receptors (agonists), by inhibiting the actions of the receptor (antagonists), or by disrupting endogenous hormone synthesis, secretion, transport or metabolism. Much of the focus to date has been on the risk of EDCs to reproductive functions, via estrogen and androgen NHRs in humans, and also in aquatic organisms. However environmental pollutants also have the potential to interact with other NHRs, particularly in aquatic environments, and cause dysregulation of other critical physiological processes, including energy homeostasis, immune functions and the stress response. To address this possibility a reporter gene assay was developed, allowing the high-throughput screening of pollutants for their interactions with piscine NHRs with critical roles in energy homeostasis, stress reponse and immune functions, namely the peroxisome proliferator-activated receptors (PPARs) and corticosteroid receptors (CRs) from European plaice (Pleuronectes platessa) and European flounder (Platichthys flesus), respectively. Complementary DNA (cDNA) sequences encoding the ligand-binding domains of PPARs and CRs, critical for receptor-ligand interactions and receptor activation, were ligated to the DNA-binding domain (DBD) of the yeast Gal4 transcription activator protein to create experimental expression plasmid constructs. Co-transfection of these expression plasmids into the fathead minnow (FHM) cell line with an upstream-activating sequence (UAS)-firefly luciferase reporter gene plasmid increased luciferase expression in the presence of known PPAR and CR ligands. Several aquatic pollutants including pharmaceuticals, industrial by-products and biocides were tested for their potential to disrupt PPAR and CR functions by interacting with these receptors in an agonistic or antagonistic manner. Several fibrates, a group of pharmaceutical compounds used to treat dyslipidemia in humans by targeting the PPARs, were able to activate plaice Gal4-PPARα and Gal4-PPARβ in the reporter gene assay, indicative of an interaction with PPAR receptors in non-target species. Fibrates which did not activate Gal4-PPARα were able to inhibit the activation of Gal4-PPARα by the PPARα-specific agonist, Wy14643, suggesting differential effects of fibrates on human and flounder PPARs. In addition some metabolites of widespread phthalate ester pollutants were also agonists of the Gal4-PPARα and Gal4-PPARβ constructs. The Gal4-PPARγ construct was unresponsive to almost all the compounds tested, including the mammalian PPARγ agonist, rosiglitazone. The exception to this was the phthalate metabolite monobenzylphthalate, which induced a small increase in firefly luciferase in Gal4-PPARγ transfected cells. All of the above effects required concentrations of at least 10 µM, which are unlikely to be encountered in the aquatic environment. In contrast bis(tributyltin) oxide (TBTO), a notorious environmental pollutant, inhibited Gal4-PPARα and Gal4-CR constructs at concentrations as low as 1 nM and 100 nM, respectively. These concentrations are lower than those reported in aquatic environments, or in fish tissues, making TBTO a candidate endocrine disruptor in fish by inhibiting PPARα and CR signalling. A European flounder cDNA microarray was used to investigate the trasnscriptional responses of flounder hepatocytes to TBTO (10 nM) exposure. Exposure to TBTO and Wy14643, both alone and in combination, indicated a TBTO-driven downregulation of several potential PPARα-target genes with functions in the immune system, the proteasome, and lipid metabolism, although, based on mammalian comparisons, some potential PPARα-target genes were also upregulated, indicating differences in mammalian and fish PPAR-target genes or reflecting the complexity of organisms at a higher organisational level than cell-based assay systems. However, the microarray-based approach was useful in formulating further hypotheses about the effects of TBTO on PPARα signalling. Overall, these results indicate that exogenous chemicals entering the aquatic environment can interfere with NHRs with functions in energy homeostasis, immune functions and stress, in non-target organisms. The cell-based reporter gene assay is a useful tool for identifying potential endocrine disruptors which target PPARs and CRs and would be a useful method in a first tier testing approach, limiting the use of live animal models and enabling investigation into specific receptors which are targets of endocrine disrupting compounds. Although more work is required to confirm the physiological consequences of TBTO inhibition of PPARα, the results presented here indicate that organisms inhabiting TBTO-polluted environments may experience suppression of the immune system, an increase in non-functional or misfolded proteins through suppression of genes involved in the ubiquitin/proteasome system and a disruption in lipid homeostasis.
289

Olfactory communication in the codling moth, Cydia pomonella L. /

Bäckman, Anna-Carin, January 1900 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniv. / Härtill 6 uppsatser.
290

La résilience du réseau logistique : une étude exploratoire dans le secteur de la production à grande échelle des produits assemblés / Supply chain network resilience : an exploratory study in the context of large-scale production of assembled products

Yao, Yuan 16 December 2014 (has links)
Cette thèse porte sur la conceptualisation de la résilience au sein du réseau logistique. La résilience a été initialement définie comme la capacité du métal à rebondir et à revenir à l'état initial face à un choc. Nous avons essayé de transposer et d'appliquer cette notion dans le réseau logistique, qui est confronté inévitablement à des aléas et subit souvent des ruptures. Après une étude conceptuelle multidisciplinaire de la résilience, nous avons tenté de définir la capacité de résilience au sein du réseau logistique dans une perspective de la Resource Based View. Selon nous, la résilience est constituée par trois caractéristiques formant un processus rétroactif: absorption, réponse et capitalisation. Une série de mécanismes qui favorisent la résilience a été identifiée à partir d'une revue de la littérature. Notre étude exploratoire prend appui sur le contexte de la production à grande échelle des produits assemblés en Chine, par une recherche empirique de vingt-deux entreprises internationales. A cette fin, nous avons réalisé des enquêtes avec des industriels et deux études de cas dans le secteur automobile et dans le secteur électronique grand public. Sur le terrain, nous avons confirmé et complété la signification de la résilience, synthétisé un processus de son fonctionnement, identifié les mécanismes qui favorisent cette capacité, les facteurs influençant sa formation et ses avantages compétitifs stratégiques. / This PhD dissertation works on the conceptualization of resilience of supply chain network. The initial definition of resilience is the quality of metal of rebounding and returning to its original shape after bending. Our study tries to transpose and apply this concept into the supply chain network, which confronts inevitably with accidents and suffers disruptions. Based on multidisciplinary literature, we have tried to develop a definition of the resilience capacity of supply chain network in the perspective of Resource Based View. In our opinion, the resilience comprises three characteristics, which form a retroactive process, absorption, response, and capitalization. We have synthesized a set of mechanisms, which are favorable for the improvement of resilience. Our exploratory and empirical study is implemented in the field of large scale production of assembling products in China, data gathered by twenty two international companies. We have carried out survey and two case studies in automotive and consumer electronics industries. By the field study, we have validated and complemented the signification of resilience, synthesized its implementation process, identified the enhancing mechanisms, and indicated the influential factors and strategic competitive advantages.

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