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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.
81

台灣企業導入阿米巴經營管理之可行性分析 / Assessment of the practicality of Taiwanese enterprises adopting amoeba management

呂怡錦, Lu, Yi Ching Unknown Date (has links)
台灣國內市場小,出口是台灣產業重要發展方向,故全球市場是台灣發展經濟重要的舞台。然而,台灣企業無論是全球主流型企業或是全球利基型企業都鮮少做到在尖端基礎科學、科技領域擁有領先的核心技術,成為該產業的領導者。 在全球激烈的競爭下,台灣企業經營者思維停留在只要繼續獲得大量的訂單,即可以保住獲利,但是台灣企業無法根本性地壓低成本,維持產品價格競爭力,去面對全球性的競爭。 本研究試圖探討京瓷、日本航空、艾訊、研華科技、崇友實業與歐洲三間公司的阿米巴經營管理實施情境,進行台灣企業導入阿米巴經營管理的可行性分析,並參照京瓷打造阿米巴組織的方式與稻盛和夫導入阿米巴經營管理至日本航空的成功案例,從中剖析導入阿米巴經營管理的台灣企業應用上產生之問題並提出適合導入阿米巴經營管理制度的台灣企業特性。 研究發現台灣企業應用上產生問題的原因有兩點,第一點為台灣企業對於阿米巴經營管理運作方式的理解程度較不足,才會產生類阿米巴的運作方式以及將阿米巴組織變動的特性視為矩陣式組織的現象;第二點為台灣的國家文化導致台灣企業長久存在的經營現象,企業認為設立較多組織階層有助於主管指揮與控制員工行為,故阿米巴領導者容易由中高階主管擔任,企業對於財務資訊的揭露仍顯得保守,因此導入阿米巴經營管理容易產生無法讓員工了解公司經營現況。 依據上述問題,分析出適合導入阿米巴經營管理的企業特性——企業領導者能將利他與為了達成崇高目標不斷地努力工作直到成功之想法注入員工思維之台灣企業、內部能精準實施阿米巴經營管理會計制度之台灣企業、資訊系統的運作能導入市場機制的台灣企業及給予員工優於勞動市場薪酬之台灣企業。 然而,真正使阿米巴經營運作得以成功的先決條件還是在於企業本身是否重視員工價值以及企業是否給予能解決艱困挑戰的員工高額薪資,員工在物質條件與心靈精神受到滿足後,為了報答公司而努力工作,才能讓企業在尖端技術領域不斷地進行攻堅與突破、在營運流程中降低不必要的費用。 / Due to the small size of Taiwan’s domestic market, exports play an important role in Taiwan’s economy. However, with limited access to core technologies, Taiwanese enterprises that excel in developing business overseas as global mainstream or niche companies rarely become top players in their respective industries. Moreover, owners of these Taiwanese enterprises tend to rely on bulk orders from overseas clients to gain corporate profits and sustain global competitiveness, but are unlikely to maintain product or service competitiveness in the global market because of failure in fundamental cost reduction. This study investigates the practice of the Amoeba Management System (AMS) when applied to Axiomtek, Advantech, Golden Friends Corporation, and three European companies. By comparing the scenario of Kazuo Inamori’s AMS in Kyocera Corporation and how he applied it to Japan Airlines with the scenario of implementing the AMS in the said Taiwanese (i.e., Axiomtek, Advantech, and Golden Friends Corporation) and European companies while analyzing the problems arising from the implementation in these companies, the study finally identifies the characteristics of Taiwanese companies that are suitable for adopting the AMS. The study findings reveal that the implementation of AMS is effective in four types of Taiwanese enterprises: (1) enterprises whose owners motivate employees toward achieving corporate goals, (2) enterprises that adequately apply the AMS to their accounting management systems, (3) enterprises that apply a market-based approach to developing their enterprise resource planning systems, and (4) enterprises that provide employees with competitive salaries and benefits packages.
82

Trade-offs And Social Behaviour In The Cellular Slime Moulds

Sathe, Santosh 10 1900 (has links) (PDF)
By combining laboratory experiments with field work, I have looked at the following aspects of cellular slime mould (CSM) biology: (a) the genetic structure of social groups (fruiting bodies) in the wild and its relation to the role of large mammals as dispersal agents; (b) social behaviour in clonal, intra-species polyclonal and interspecies social groups and (c) fitness-related trade-offs with respect to life history traits as a possible mechanism for coexistence and cooperative behaviour in CSMs. The major findings of this study are as follows: (a) individuals belonging to different strains of a species, different species and genera occur in close proximity, even on a speck of soil (250µm–1mm) or the same dung pat; (b) social groups formed in the wild by Dictyostelium giganteum and D. purpureum are generally multiclonal; (c) genetically diverse strains can co-aggregate and form chimaeric social groups; (d) in chimaeric social groups, strains differ in their relative sporulation efficiencies; (e) the fact that strains co-exist in spite of this may be attributable in part to trade-offs between various fitness-related traits as can be demonstrated in the case of wild isolates of D. giganteum in pair wise mixes. The Dictyostelids or CSMs are haploid, eukaryotic, soil dwelling social amoebae with an unusual life cycle (Bonner, 1967; Raper, 1984). They exist as single cells in the presence of food (bacteria, yeast, fungal spores). Once the food is exhausted, they enter the social phase of their life cycle. Approximately 102 to 106 amoebae aggregate at a common collection point and form a starvation resistant structure called the fruiting body. In many species a fruiting body is made up of an aerial stalk of dead cells and a ball of viable spores on top. In other CSM species (not part of this study), all amoebae in a fruiting body differentiate into spores and the stalk is an extracellular secretion. The CSM life cycle raises fundamental questions related to the evolution of an extreme form of ‘altruism’ in the form of reproductive division of labour in social groups. The spore–stalk distinction in the CSMs is analogous to the germ–soma distinction in metazoans, although, the CSMs achieve multicellularity not by repeated divisions of a zygote but via the aggregation of many cells which may or may not be clonally related (Bonner, 1982; Kaushik and Nanjundiah, 2003). Social behaviour in the CSMs offers interesting parallels to what is seen in the social insects (Gadagkar and Bonner, 1994). The origin and maintenance of ‘altruism’ has been a long-standing issue in sociobiology. Because of their simple life cycle and experimental tractability, the CSMs are ideal for studying the evolutionary origin and maintenance of social behaviour, in particular of ‘altruistic’ behaviour. By elevating spores above soil level, stalk cells, protect them from noxious compounds and predators present in soil and also facilitate their passive dispersal. In the course of doing so they die. The death of stalk cells appears to be an extreme form of altruism. Knowledge of the genetic structure of social groups and populations including patterns of kinship is essential for modelling the evolution of ‘altruism’. Thus, it is important to understand the genetic structure of CSM social groups in the wild. For this, social groups (fruiting bodies) of CSMs were isolated from undisturbed forest soil of the Mudumalai forest reserve in South India. Soil and animal dung samples were brought to the laboratory and quasi-natural social groups were generated by inoculating the samples on non-nutrient agar. The fruiting bodies from various CSM species were formed by these isolates. Since soil and dung samples were not perturbed in any way, the fruiting bodies were formed as they would have in nature. When compared to soil, dung samples contained a higher CSM diversity and more CSM propagules. The presence of CSMs in fresh animal dung makes it likely that they were transported and dispersed over long distances through the gut of these animals. Such dispersal is likely to be preceded by a thorough mixing of spores in the gut. That increases the probability of co-occurrence of different genotypes in a social group. This possibility was confirmed by genetically characterizing spores in social groups of Dictyostelium giganteum and D. purpureum collected from the wild. Random amplification of polymorphic DNA (RAPD), a simple and reliable molecular technique, was used for genotyping spores within a fruiting body. 17 fruiting bodies (8 from animal dung and 9 from soil) were studied. 15 out of 17 (9 out of 11 of D. giganteum and 6 out of 6 D. purpureum) were polyclonal; the minimum number of distinct clones in a single fruiting body was 3 to 7 (animal dung) and 1 to 9 (soil). Therefore in D.giganteum and D. purpureum, chimaeric social groups seem to be the norm. This suggests that other species of CSMs form intra-species chimaeric social groups in wild, though clonal fruiting bodies occur too. The next objective of this thesis was to test whether genetic heterogeneity had functional consequences. That is, when different strains come together in an aggregate, do they contribute equally to the reproductive (spore) and non-reproductive (stalk) pathways? Amoebae of different clones (strains) of D. giganteum or D. purpureum were mixed and developed together and the number of spores formed by each strain was counted. These experiments confirmed that strains of D. giganteum or D. purpureum can aggregate together and form chimaeric fruiting bodies. The ability to mix (measured as the frequency of chimaerism) depended on the strains used and varied from one mix to another. One strain was often found to ‘exploit’ the other during sporulation, that is, it formed more spores than its expected share. Despite this, strains are found in very close proximity in the soil, which raises an important question: when one strain is more efficient at sporulating than other, how can the two co-exist stably? To investigate what might lie behind the stable co-existence of strains, I studied various fitness-related traits in the life cycle of D. giganteum. They included the rate of cell division, the time taken to go through multicellular development, the efficiency of slug migration through various depths of soil and the probability of differentiation into a spore. Measurements were carried out on strains taken separately and on their pair wise mixes. Five different D. giganteum wild strains (46a3, 46d2, 48.1a1, F5 and F16) were used. All were isolated from the Mudumalai forest (India). 46a3 and 46d2 came from soil within 10 cm of each other, 48.1a1 from soil about 200m away from 46a3; and F5 and F16 from the same fruiting body (Kaushik et al., 2006; Sathe et al., 2010). Members of a pair differed significantly in the measured fitness-related traits. For example, in the case of 48.1a1 and 46d2, 48.a1 grew faster than 46d2 both individually and in a mix. After starvation, 48.1a1 formed fruiting bodies faster than 46d2; a mix of the two developed at the rate of the faster member, implying that the slower one (46d2) gained from the association with 48.1a1. During slug migration, slugs formed by 48.1a1 came up through a higher depth of soil than 46d2 slugs and did so earlier. Chimaeric slugs were like the more efficient member, 48.1a1, in terms of the maximum depth of soil that was covered, but like the less efficient member, 46d2, in terms of the time taken for slugs to be seen on the soil surface. 48.1a1 seems to have an advantage over 46d2 in all these respects. However, during sporulation in chimaeras, 48.1a1 formed relatively fewer spores than 46d2. Similar trade-offs were seen in all mixes. F5 and F16 displayed an unexpected feature during sporulation; the spore-forming efficiency of either strain depended on its proportion in the initial mix in a frequency-dependent manner that was consistent with a stable equilibrium. Thus, trade-offs between different fitness-related traits contribute to the co-existence of strains. Next, I studied interactions between members of different CSM species. Several species of CSMs were isolated from the same environment (Sathe et al., 2010); a question of interest was to see if amoebae of different species came together to form a chimaeric multicellular body. Five strains (two D. purpureum and three D. giganteum) were used in this study. Amoebae of D. giganteum and D. purpureum co-aggregated. However, there were factors that caused amoebae of the two species to sort out thereafter. The extent of segregation differed between strains, a characteristic that inter-species mixes share with intra-species mixes. In conclusion, the ability of cellular slime moulds to form multiclonal social groups in the wild suggests that one should look to factors in addition to close relatedness to understand the evolution of CSM social behaviour. The existence of fitness-related trade-offs between different traits indicates that individual-level selection can also contribute to the maintenance of chimaeric social groups.
83

Étude de la prolifération d'Acanthamoeba castellanii suite à l'infection par Legionella pneumophila / Study of proliferation of Acanthamoeba castellanii upon infection by Legionella pneumophila

Mengue Assoumou Louma, Luce Laétitia 05 April 2017 (has links)
Acanthamoeba castellanii est une amibe libre ubiquiste de l'environnement. Elle se nourrit principalement de micro-organismes par phagocytose. Seulement, certains micro-organismes ont développé des mécanismes de résistances qui leur permettent d'échapper à la digestion et même de se multiplier à l'intérieur des amibes. C'est le cas de Legionella pneumophila, bactérie responsable de la légionellose. Legionella pneumophila, à travers son système de sécrétion Dot/Icm, injecte plusieurs effecteurs à l'intérieur de son hôte. Ces effecteurs interagissent avec les protéines de l'hôte, et induisent une modification de la physiologie de son hôte, à son avantage. Durant ma thèse, nous nous sommes intéressés aux effets de Legionella pneumophila, sur la prolifération de son hôte amibien. Nous avons montré que Legionella pneumophila arrête la prolifération d'Acanthamoeba castellanii. Ce phénotype était associé une modification de la forme, à une perte d'adhérence et à une baisse de motilité de l'amibe. Sur le plan moléculaire, Legionella pneumophila induit une baisse dans l'expression du gène cdc2b, qui présente des similarités avec le gène cdk1 (cyclin dépendant kinase), codant pour la CDK essentielle au déroulement du cycle cellulaire chez les mammifères. L'arrêt de la prolifération d'Acanthamoeba castellanii, qui passe par une réduction d'expression de cdc2b, est certainement induit par un ou plusieurs effecteur(s) de Legionella pneumophila, car le mutant ΔdotA de L. pneumophila, défectueux au niveau de l'appareil de sécrétion Dot/Icm, n'induit pas l'arrêt de la prolifération d'Acanthamoeba castellanii. / Acanthamoeba castellanii is an ubiquitous free-living amoeba of the environment. This amoeba feeds mainly on micro-organisms by phagocytosis. However, some micro-organisms have acquired resistances that allow them to escape digestion and even multiply inside amoebae. This is the case of Legionella pneumophila, the bacterium responsible for legionellosis. Legionella pneumophila, through its Dot/Icm secretion system, injects several effectors into its host. These effectors interact with the proteins of the host, and induce a modification of the physiology of its host, to its advantage. During my phD, we were interested in the effects of Legionella pneumophila infection on the proliferation of its amoebic host. We showed that Legionella pneumophila prevents the proliferation of Acanthamoeba castellanii. This phenotype was associated with a modification of the shape, a loss of adhesion and a decrease in motility of the amoeba. On the molecular level, Legionella pneumophila induces a decrease in the expression of the cdc2b gene, which share similarities with the cdk1 (cyclin dependent kinase) gene, coding for the major CDK of the mammalian cells cycle. The arrest of proliferation of Acanthamoeba castellanii, which involves a reduction in expression of cdc2b, is certainly induced by one or more effector(s) of Legionella pneumophila, because the mutant ΔdotA of L. pneumophila, defective in the Dot/Icm secretion apparatus, does not induce proliferation arrest of Acanthamoeba castellanii.

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