Tesis sobre el tema "BL1600"

The thesis is focused on the calculation of electrodynamic forces that counterwork on moving contacts of compact circuit breaker BL1600 from the company OEZ Letohrad. The thesis is divided into separates chapters that build on themselves. In the introduction the reason why we deal with calculation of dynamic forces and structural arrangement of current carrying path is described. In the following chapter there is a theoretical analysis of electrodynamic forces that conterwork on individual parts of circuit breaker´s element. The third part is devoted to structural arrangement of the circuit breaker BL1600. In this part we can find an example of using the circuit broker Modeion in practice. Two next chaptures deal with adjustment of the model of current carrying path which then serves for the calculation of electrodynamic forces. The rest of the thesis is devoted to my own calculations. These calculations are mainly stationary where we try to find the forces that conterwork on the contacts in a steady current and in a point in time. There are also dynamics calculation when we can watch the forces that counterwork on contacts in a certain time interval. The last chapter is devoted to a stationary calculation of forces that counterwork on the electrical arc which arises while turning the short-circuit current off. The obtained results are evaluated in partial conclusions of this thesis.

This study explores how the corporal punishment experienced by learners in Nepalese schools can impact upon multiple aspects of their lives. I examine how these short and long-term effects can extend into adulthood using an auto/biographical methodology; from a perspective influenced by my own encounters as a corporal punishment survivor from Nepal. Corporal punishment continues to be used in Nepalese schools, with the support of many teachers, parents and school management committees, despite several government policy initiatives and court rulings against it. In contrast to worldwide developments (notably in Scandinavia and America), research into corporal punishment in Nepal tends to be rare, quantitative and focused upon the prevalence and short-term effects as described by group participants and newspaper articles. This study addresses the urgent need to increase public awareness, using personal accounts describing the long-term outcomes of corporal punishment, with a depth of detail facilitated by an auto/biographical research methodology. Participants in the study expressed feelings of relief and increased self-understanding, although for myself at least, these were accompanied by feelings of grief and confusion. The lives of five corporal punishment survivors are explored through a series of interviews carried out in the Devchuli municipality of Nawalparasi, Nepal, between November 2015 and January 2016. The first is my own story, the second is a pilot interview and the other three are discussed under the themes of immediate compliance, severing dichotomies, disempowered bodies and the spiritual threat of spatio-temporal appropriation. The participants, whose identities are protected, look back, as adults, upon their experiences of corporal punishment at school and consider possible links between these and their current social, political, economic and spiritual challenges. Simultaneously, the study questions whether ‘effects’ can ever be conceptually or temporally contained within ‘multi-faceted’ and ‘becoming’ identities, using examples from the participants’ self-appraisals. I examine literature from the global debate on the effects of corporal punishment upon children, including the contrasting methodologies of Murray Straus, Alice Miller and Elizabeth Gershoff. The impact of corporal punishment upon notions of personhood is explored using Theodor Adorno’s interpretation of reification and comparable notions of objectification challenged by Andrea Dworkin, Martha Nussbaum and Paolo Freire. Corporal punishment is discussed in relation to power, conflict and the Holocaust, using Adorno and Bauman’s descriptions of authoritarian behaviours and immediate compliance, and Nietzsche and Foucault’s notions of punishment as a spectacle. Conditions for the possibility of corporal punishment are located to traditions deifying teachers, judgement-based belief systems and neo-liberal ideologies of competition and performativity. These are contrasted with alternative, non-punitive pedagogical and theological resources. Participants explore the ways in which healing and holistic self-development can be blocked by everyday vocabularies of violence and conditionality, triggering destructive individual and collective over-determined reactions. My study ‘concludes’ with reflections upon how corporal punishment has affected my participants’ lives: with their social roles hampered by defensive masks and evasive dances; their political lives blocked by fears of punishment; their economic lives stilted by caution and low self-esteem and their spiritual lives distorted by disenchantment and disappointment. Methodology and theory converge as my study rejects inherently disciplinarian, Enlightenment-led demands fo**r rational or scientific ‘proof’ of psychological effects, by presenting auto/biography itself, especially ‘child-standpoint’ narratives, as valid revolutionary praxis, effervescent with resistance to punitive ideologies and practices and dedicated to the liberation of our present from a painful past.

碩士
國立成功大學
生物科技研究所
102
Aurantiochytrium sp. strain L-BL10 is a eukaryotic microalgae that incurs lower culture costs, displays higher growth, and has lower rates of cell wall generation (amoeba cells) than other eukaryotes currently being used to express foreign proteins. The objective of this study was thus to construct a transgenic platform for exogenous gene expression in L-BL10. For this, we first designed nucleic acid constructs. L-BL10 genome databases were accessed during platform design to predict and correct codon usage bias within the gene sequences. We obtained housekeeping genes, which included: (1) the promoter and terminator sequences of the elongation factor 1-α (EF-1α) and (2) the sequences of 18s ribosomal DNA. Next, we selected green fluorescent protein (GFP) gene, red fluorescent protein (RFP) gene, and neomycin phosphotransferase II (NPT II) gene. Those genes replaced sequences of the elongation factor, thereby serving as the reporter genes or selection markers in gene cassettes. For these, we coated the nucleic acids with different proportions of Lipofectamine or performed electroporation under different pulsed conditions. From the 16 predicted gene sequences of L-BL10, we recorded 16,788 instances of codon usage bias, among which the usage rates of UUA, CUA, AUA, and CGA in corresponding codons of the same amino acid were less than 1%. We had already completed gene cassettes during nucleic acid construction. Finally, we successfully transferred GFP gene sequences into cells using electroporation and Lipofectamine, and we detected the mRNA of exogenous genes. In addition, we observed green fluorescent signals in the algal cells transformed using Lipofectamine.

碩士
國立成功大學
生物科技研究所
102
Unlike other eukaryotes, which primarily possess unsaturated fatty acids, Aurantiochytrium sp. strain L-BL10 is characterized by docosahexaenic acid (DHA). Previous researchers have found that incubating L-BL10 with cerulenin failed to decrease the amount of DHA, indicating that palmatic acid is not the precursor of DHA. After analysis of the draft genome of L-BL10 revealed a number of partial genes resembling segments of the polyketide synthase (pks) gene, which is responsible for synthesizing DHA in Schizochytrium sp. During L-BL10 cultivation, DHA were observed accumulating soon after the up-regulation of pks genes. Those findings suggest that PKS enzyme involved in the synthesis of DHA in L-BL10. However, the amount of protein products produced in the various stages of DHA synthesis remains unclear. This study prepared a PKS antibody to elucidate the changes in polyketide synthase protein product. We designed epitopes and then used template-repeated polymerase chain reaction (TR-PCR) and adapter polymerase chain reaction (AD-PCR) to create linear array epitopes (LAE). And produce antibody by rabbit and mice. Finally, we used western blot and LC-MS/MS to identify and analyze PKS. LC-MS/MS results revealed that PKS A, B, and C comprised 18%, 58% and 24% coverage, respectively, compared with the L-BL10 polyketide synthase database. Western blot showed that PKS B and C produced strong signals at 20-28 hours. Finally, we suggested that L-BL10 use PKS to produce DHA. It is able to withstand stress in nitrogen deficient.

碩士
國立成功大學
生物科技研究所碩博士班
101
Aurantiochytrium sp. BL10 is one of the few thraustochytrid strains that exist as amoeboid cells at some point during their life cycle. Thus, we sought to identify the bio-functions of amoeboid cells and investigate the molecular mechanisms which underlie the transition between vegetative and amoeboid phases. Previous observations related to the formation and migration of amoeboid cells led to hypotheses about these possible mechanisms. This current study found that amoeboid cells only exist when the culture is in the exponential stage of growth, such that extensive cell division significantly decreases oxygen levels, leading to a sudden expansion of the amoeboid cell population. When BL10 was cultivated on agar plates, amoeboid cells always formed in the border region of a colony, moving away from areas of greater cell densities where the accumulation of various macromolecules acted as a chemorepellent. Autocrine substances were extracted from the cultured agar using water and then separated using a molecular sieve or gel filtration column. Certain substances were observed to affect the formation of amoeboid cells, the molecular weight of which should be between 30 and 100 kDa. Other substances affected the migration of amoeboid cells. According to the results of a cell migration assay, the extract should have both chemorepellent and chemoattractant ,and their molecular size should be between 30-100kDa and 10-30kDa. Our results confirm that the formation of BL10 amoeboid cells is affected by the amount of dissolved oxygen, such that lower levels of dissolved oxygen within the medium resulted in a higher proportion of amoeboid cells. The formation and migration of amoeboid cells was also affected by autocrine signaling. So far, an active-test platform and a method of separating substances have been established, and the identification of these autocrine substances has been initiated.

碩士
國立成功大學
生物科技與產業科學系
106
Our objective in this study was to establish a protocol by which to achieve the stable expression of foreign genes in the Aurantiochytrium strain BL10. To confirm the presence and expression of foreign genes in BL10 cells, we constructed 15 linear or circular expression cassettes, which were then transformed into BL10 via electroporation and then selected on antibiotic agar plates. The cassette with the P1 promoter and yeast-maintain-sequence, CEN6-ARSH4-HIS3 (CAH), presented the highest transformation efficiency, the transformants of which stably expressed the foreign gene after being subcultured four times. This may be attributable to the pronounced activity of the P1 promoter and CAH sequence, which makes it possible for the foreign gene to be maintained as an episome rather than undergoing integration into the chromosome. Subsequent confirmation will confirm whether the foreign gene is maintained as episome.

碩士
國立成功大學
生物科技研究所碩博士班
101
Aurantiochytrium sp. strain L-BL10 is rich in C22 polyunsaturated fatty acids (PUFAs), DHA (C22:6n-3), and DPA (C22:5n-6); however, this species contains very few PUFAs with 18 and 20 carbons. Previous studies in our laboratory demonstrated that adding fatty acid synthase (FAS) inhibitor to a L-BL10 culture failed to decrease the percentages of DHA and DPA. These earlier results revealed that, in addition to the standard pathway, a secondary biosynthesis pathway is involved in the production of these two PUFAs in L-BL10. The purpose of our current research was to identify enzymes capable of catalyzing the synthesis of PUFAs along this specific biosynthetic pathway. First, several genes suspected of being involved in PUFA production were synthesized from the L-BL10 genome sequence and NCBI database. We then predicted the functional domains using SMART (Simple Modular Architecture Research Tool) software and investigated the enzyme classification according to functional domain arrangement and phylogenetic analysis. In addition, we examined gene expression over various incubation times using real-time PCR. These efforts revealed that 8 polyketide synthase (PKS)-like genes may be involved in the production of DHA and DPA in Schizochytrium sp. ATCC 20888. Previous researchers confirmed that the polyketide synthase of ATCC 20888 comprises three genes, pksA, pksB, and pksC. The results of this current study further demonstrated that L-BL10 has three complete polyketide synthase genes, which are similar to Schizochytrium sp. ATCC 20888. The lengths of these genes are 10068, 6117, and 4386 base pairs, respectively. We also identified the functional domains capable of synthesizing PUFAs, such as ketoacyl synthase, malonyl-CoA:ACP acyl transferase, acyl carrier protein, ketoacyl-ACP reductase, enoyl reductase, chain length factor, acyl transferase, and dehydratase functional domain. These results indicate that L-BL10 should have the ability to synthesize PUFAs. Moreover, the PKS of L-BL10 was shown to belong to Type I iterative PKS according to its arrangement of functional domains and the results of phylogenetic analysis related to KS domains. Conversely, we found that PKS gene expression reached the culminating point when L-BL10 was in the last stage of log phase (after culturing for 20 hours). At this point, the nitrogen source on the culture plate was depleted and L-BL10 began using the carbon source. Thus, we surmise that the PKS gene may be regulated by its nutrient source, such that the co-existence of a carbon source and nitrogen source on the culture plate prevents induction of the PKS gene. Nonetheless, these conditions could promote the accumulation of DHA and DPA when induced by only a carbon source on the culture plate.

碩士
國立成功大學
生物科技研究所碩博士班
100
BL10 is a marine heterotrophic microalga that isolated from the stream outlet of northern Taiwan, it has many unique characteristics, including (1) euryhaline, it able to grow within the salinity range from 2 to 35 ppt; (2) saccharophilic, its growth not inhibited when the cell cultured in medium containing high glucose concentrations (140 gL-1); (3) oleaginous, its oil accumulated more than 80% of the dry biomass; (4) culture easily, the biomass can reach 120 gL-1 at 72 hour that inoculated with the initial cell concentrations of 0.01gL-1; (5) unique lipid metabolism pathway, and (6) special life cycle in BL10 that contains mobile zoospores and irregular-shaped amoeboid cells (the cell with crawling ability), making BL10 a nice candidate to become a new model organism, which can be used to study osmotic regulation, the production and accumulation of lipid, the long chain polyunsaturated fatty acids synthetic pathway of microalgae, and cell migration. However, the available information is insufficient to establish a model organism, including (1) the taxonomy of BL10 (2) the genome size and karyotype of BL10 (3) gene manipulation of BL10. Therefore, the purpose of this study is to resolve the above issues. First, in order to identify the species of BL10, the 18S rDNA sequence were used to construct the phylogenetic tree. The results of a molecular phylogenetic analysis showed that BL10 belongs to the genus Aurantiochytrium and closely relates to A. limacinum. From the results of morphological observation, we found that BL10 can be easily observed the formation of amoeboid cells, and the amoeboid cells can divide into numerous zoospores after the cell settlement down. The above results showed that BL10 is similar to A. limacinum, while BL10 is unable to form the sporangium that significant different with A. limacinum.However, we consider that these results can not support the taxonomy of BL10. On the other hand, we found that amoeboid cell with thin cell wall (or without cell wall), and the percentage of amoeboid cells could be enhanced up to 16% of total cells by regulating the medium composition and acquired at specific time. Those results provide information that it's possible to do gene transformation or dsRNA delivery for genomic functional analysis of BL10. Then we established the genome size by flow cytometry, and used Saccharomyces cerevisiae W303-1A (12 Mbp) as control to calculate the genome size of BL10 (40.5 Mbp) that based on FL3 intensity. And in the karyotype analysis experiment, we used 8-hydroxyquinoline to arrest the cell cycle at the metaphase, and the chromosomes of BL10 were stained with DAPI and observed by fluorescence microscopy. The experimental results showed that BL10 has three chromosomes. Then we proved that the BL10 is a haploid using fluorescence in situ hybridization with a 45S rDNA probe. According to our results, we believe that the work of whole genome sequencing is possible.

碩士
國立成功大學
微生物及免疫學研究所
105
Non-typhoid Salmonella (NTS) is not only a zoonotic disease, but also an important food-borne disease, usually causing diarrhea, gastroenteritis. With the spread of drug resistance, multiple drug resistant strains have caused a major public health concerns. In order to clarify the relationship between animal and human resistance distribution, we used next generation sequencing (NGS) to carry out the whole genome sequence of a multiple drug resistant strain BL10, and determined that the genome of BL10 have more than 20 drug-resistant genes, all of which located on plasmids. In addition, we also use BL10 as reference strain to analyze similar genes from four other multi-drug resistant strains. We found that all five strains have the constant resistance genes and plasmids, showing that the drug resistance genes might have spread between humans and animals. Results here suggest that if we do not effectively control the use of antibiotics, drug resistance will become a great threat to human health and the economy. Only from the perspective of “One Health” (environmental, animal and human) to control antibiotics, will we able to ensure the health of public.

碩士
國立成功大學
生物科技研究所碩博士班
101
Aurantiochytrium sp. L-BL10, an oleaginous microalgal strain rich in DHA, is a promising candidate for the production of vegetative DHA. The sole concern limiting the use of L-BL10 is the co-existence of palmitic acid (PA), an undesirable fatty acid which counteracts the human health effects of DHA. In the past, PA production was reduced through treatment with cerulenin, an inhibitor of fatty acid synthase. Unfortunately, cerulenin is an antibiotic that can negatively affect food safety. The purpose of this research was to reduce PA production in L-BL10 through RNA interference (RNAi) of the fatty acid synthase gene (fas), inhibits the synthesis of fatty acid synthase (FAS) proteins and mutagenesis. In this study, we first sequenced fas and then designed real-time PCR primers in order to analyze gene expression patterns over various durations following incubation. These results provided a foundation for the following investigation. After ascertaining the appropriate timing, we conducted RNAi analysis on fas dsRNA and treated this gene with morpholino in order to inhibit FAS protein synthesis. For mutagenesis, we first determined the correct dose of MNNG mutagen and then treated L-BL10 with MNNG to obtain mutant lines. The fatty acid composition of the mutant lines was analyzed using GC/MS. fas sequencing was completed to a length of 13257 bps. fas expression was up-regulated after 16 hrs of incubation, representing the late logarithmic phase of cell growth. At this point, dsRNA was combined with Lipofetamine to induce RNA interference; however, these treatments did not significantly inhibit FAS gene expression. Regarding the inhibition of protein synthesis, the efficiency of transfection was found to be only 0.2 %. In order to facilitate inhibition tests, it would be necessary to modify the conditions of transfection. Regarding mutagenesis, a concentration of 0.68 mM MNNG caused a 1.35 % reduction in cell survival rate. Under these conditions, we selected 150 lines of mutant strains, 5 of which were identified as having low PA accumulation compared with the original line. In the mutant line M48, the reduced PA ratio was as high as 8.38 %. These results suggest that mutagenesis has the potential to reduce PA production.