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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

Targeting of Ecosystem Goods and Services:Directing Agri-Environmental Policy Innovation

2013 April 1900 (has links)
There has been active development and implementation of agri-environmental policies dealing with the provision of ecosystem goods and services over the years. However, these policies have often not been directed towards certain lands with the greatest potential for producing environmental benefits and those areas where the benefits are greater relative to cost. The limited budgets allocated to agri-environmental programs, and the often large and heterogeneous nature of agricultural landscapes, makes policy efficiency an important consideration. Incorporating targeting mechanisms in the design of agri-environmental policy instruments could improve the efficiency of such policies. This thesis illustrates the efficiency gains from policy targeting, by applying three targeting protocols and a hybrid method using representative wildlife habitat conservation policy approaches that set-aside land from crop production by purchasing or leasing land. The GIS land selection models developed for this research assessed the net benefits for wildlife based on the opportunity cost of idling land from agricultural production. As indicated by the results, policy delivery using targeting mechanisms selectively enrolls significantly greater areas of wetlands and natural vegetative cover. Thus, targeted policy enrolled land will provide greater wildlife habitat and other environmental benefits compared to the baseline landscape which represents a non-targeted land enrollment and hence increase the environmental benefits of the program for a given budget.
82

The Analysis of Competitive Strategy for Semiconductor Equipment Distributor to Implement New Product into Target Market- A Case Study of A Company

Hsu, Chih-Hsiang 05 February 2009 (has links)
The life cycle of the semiconductor equipment industry has evolved from a fast growth high profit ramp-up phase to one of much slower growth and intense competitiveness that has squeezed profit margins. In this environment, one of the key success factors for semiconductor equipment suppliers is product management. A correct product planning and implementation strategy will generate a healthy market performance and profitable business operations. Semiconductor equipment manufacturers and agents need to consider their product competencies to develop a planning strategy for new product introduction, which includes product positioning, target market selection as well as new product introduction guidance and evaluation procedures. This thesis focuses on industrial data analysis and a case study based on face-to-face interviews with several people at various positions within semiconductor equipment suppliers. The major approach of this study is a description of competitive strategy through a qualitative analysis of the industry, and an analysis the key factors¡Xincluding product management, product lifetime cycle and knowledge management¡Xthat influence the technology service ability of an equipment company. The conclusions of this study are presented as follows: 1. Semiconductor agency has to introduce new product to different market segments for its product life time extension or future business development as well as product competence enhancement. 2. New technology development trends become a threat to existing technology and products, which will replace current products in the market within a short period. 3. Product management needs a procedure to evaluate the new product and the service income potential in order to assess the product¡¦s profit and loss prospects. Then the management can adjust the business priorities to maximize total company revenue through periodic review. Future studies should consider the effect of changes in the industrial structure and/or the market environment and analyze the impact on market development risks and strategies. Keywords: Semiconductor Equipment Agency, Product Management, Targeting Market, Resource Based, Knowledge Management
83

Biomaterials modeling of localized hyperthermia and drug delivery for breast cancer

Mulamba, Peter, January 2009 (has links)
Thesis (Ph. D.)--Ohio State University, 2009. / Title from first page of PDF file. Includes bibliographical references (p. 305-320).
84

Synthesis of water soluble organophosphines and phospine-peptide conjugates : investigations on the biomedical utility of their transition metal complexes /

Pillarsetty, Nagavarakishore, January 2003 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves 186-205). Also available on the Internet.
85

Synthesis of water soluble organophosphines and phospine-peptide conjugates investigations on the biomedical utility of their transition metal complexes /

Pillarsetty, Nagavarakishore, January 2003 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves 186-205). Also available on the Internet.
86

Bacterial gene targeting using group II intron L1.LtrB splicing and retrohoming

Yao, Jun, 1974- 10 September 2012 (has links)
The Lactococcus lactis Ll.LtrB group II intron retrohomes by reverse splicing into one strand of a double-stranded DNA target site, while the intron-encoded protein cleaves the opposite strand and uses it as a primer for reverse transcription of the inserted intron RNA. The protein and intron RNA function in a ribonucleoprotein particle, with much of the DNA target sequence recognized by base pairing of the intron RNA. Consequently, Ll.LtrB introns can be reprogrammed to insert into specific or random DNA sites by substituting specific or random nucleotide residues in the intron RNA. Here, I show that an Escherichia coli gene disruption library obtained using randomly inserted Ll.LtrB introns contains most viable E. coli gene disruptions. Further, each inserted intron is targeted to a specific site by its unique base-pairing regions, and in most cases, could be recovered by PCR and used unmodified to obtain the desired single disruptant. I also demonstrate that Ll.LtrB introns can be used for efficient gene targeting in a variety of Gram-negative and positive bacteria, including E. coli, Pseudomonas aeruginosa, Agrobacterium tumefaciens, Bacillus subtilis, and Staphylococcus aureus. Ll.LtrB introns expressed from a broad-host-range vector or an E. coli-S. aureus shuttle vector yielded targeted disruptions in a variety of test genes in these organisms at frequencies of 1-100% without selection. By using an Ll.LtrB intron that integrates in the sense orientation relative to target gene transcription and thus could be removed by RNA splicing, I disrupted the essential gene hsa in S. aureus. Because the splicing of the Ll.LtrB intron by the intron-encoded protein is temperature-sensitive, this method yields a conditional hsa disruptant that grows at 32oC, but not at 43oC. Finally, I developed high-throughput screens to identify E. coli genes that affect either the splicing or retrohoming of the Ll.LtrB intron. By using these screens, I identified fourteen mutants in a variety of genes that have decreased intron retrohoming efficiencies and additional mutants that have increased intron retrohoming efficiencies, in some cases apparently resulting from increased stability of the intron RNA. / text
87

Effective DNA delivery mediated by pH responsive peptides

Chan, Fu-lun., 陳賦麟. January 2012 (has links)
Non-viral vectors have been used to deliver therapeutic genes to treat different diseases. There are a variety of non-viral vectors such as liposomes, cationic polymers and peptides. Among all, pH responsive peptides showed excellent DNA transfection efficiency in many types of cell. These peptides are capable of changing their structural conformation as pH decreases, adopting a disordered structure which can destabilize endosomal membrane and therefore enhancing the release of DNA from endosomes into cytosol. Traditional pH responsive histidine-rich peptides showed good DNA transfection efficiency and low toxicity to the cells when compared with other non-viral vectors. However, their low pKa value restricted these peptides to be protonated only at late endosomal stage, in which DNA is extremely susceptible to endosomal degradation. This hindered the DNA to be released to the cytosol efficiently and therefore reduced DNA transfection efficiency. In response to this, it is of great interest to probe into the insertion of either 2,3-diaminopropionic acid (Dap) or methylated-2,3-diaminopropionic acid Dap(Me) to the peptide as alternative pH sensitive components. The pKa values for both Dap and Dap(Me) peptides are higher than that of histidine. It is anticipated that the higher pKa value, the protonation of peptide could be happened at an earlier stage of endosomal maturation. Such protonation of peptide destabilizes the endosome membrane rapidly, causing the release of DNA to the cytosol effectively and hence improving DNA transfection efficiency. In this experiment, LADap(Me)4-L1 peptide was the optimal candidate within the series. It showed good DNA transfection efficiency and cell viability in A549 cells among all Dap and Dap(Me) peptides. / published_or_final_version / Pharmacology and Pharmacy / Master / Master of Medical Sciences
88

Gene targeting to study a novel testis-specific gene Vad1.2 in spermatogenesis

Cao, Shanbo, 曹善柏 January 2012 (has links)
Spermatogenesis is regulated by steroid hormones which induce expression of various genes responsible for the growth, proliferation and differentiation of spermatogonia to form mature haploid spermatozoa. The surrounding somatic cells including Leydig and Sertoli cells support the whole process in vivo. Previously, we used the post-vitamin A treated vitamin-A-deficient (PVA-VAD) rat model to study spermatogenesis, and identified 24 genes that are differentially up-regulated after retinol treatment. Vad1.2 is one of the up-regulated transcripts expressed in the rat testis from postnatal day 25. Vad1.2 transcript is localized to the round and elongating spermatids in the adult mouse testis. In silico analyses showed that Vad1.2 transcript is down-regulated in patients with teratozoospermia and non-obstructive azoospermia, suggesting that Vad1.2 may have important roles in spermatogenesis. However, how Vad1.2 affects spermatogenesis remains unclear. Therefore, the present study was designed to study the functional roles of Vad1.2 protein in mice using gene targeting approach and investigate the molecular changes in mice with Vad1.2 deficiency. Vad1.2 polyclonal antibody was raised against the full-length mouse Vad1.2 recombination protein and affinity purified. Vad1.2 protein was localized to the cytoplasm and flagellum of condensing spermatids, specifically to the fibrous sheath (FS) in cauda epididymal spermatozoa. Vad1.2 conditional knockout vector was constructed and used to generate Vad1.2 null mice. Vad1.2-/- male mice developed normally but were subfertile with reduced sperm count and motility. Vad1.2-/- male mice had smaller testis and higher incident of sloughing of immature germ cells into the seminiferous lumens when compared to the wild-type. Yet, the rates of germ cell proliferation and apoptosis were similar between the wild-type and the mutant testis. Interestingly approximately 50% of the mutant cauda epididymal spermatozoa showed deformed flagella and demonstrated structural defects typically associated with bending of flagellum at the principal piece or at the midpiece/principal piece junctions. The acrosome, nucleus and mitochondrial sheath of these spermatozoa appeared normal, while the flagellum displayed structural abnormalities including deformation of the two longitudinal columns of the FS and disruption of a portion of FS, suggesting that Vad1.2 might be involved in the biogenesis of FS in spermatogenesis. Furthermore, Vad1.2 interacted with Akap4 in vivo, and the two proteins were co-immunoprecipitated from the testis or cauda epididymal spermatozoa lysates. Akap4 and Vad1.2 were localized to the tail region of the testicular spermatids and cauda epididymal spermatozoa. The expression levels of pro- and mature Akap4 in Vad1.2-/- testes were markedly increased when compared with the wild-type mice. However, a significant decrease of Akap4 was found in the mutant cauda epididymal spermatozoa, suggesting that most of the mature Akap4 failed to incorporate into the FS. Taken together, Vad1.2 plays an important role in spermatogenesis and Vad1.2 deficiency leads to subfertility in mice with the deformed flagella in mature spermatozoa. Further studies on the regulation of FS formation may uncover the underlying molecular changes associated with Vad1.2 deficiency, and may provide fundamental information for treatment of infertile patients with FS defect in the spermatozoa. / published_or_final_version / Obstetrics and Gynaecology / Doctoral / Doctor of Philosophy
89

Analysis of abnormal phenotypes of Hoxb3 mouse mutants generated by gene targeting

Wong, Kung-yen, Corinne., 黃共欣. January 2003 (has links)
published_or_final_version / abstract / toc / Biochemistry / Master / Master of Philosophy
90

Characterization of Karyopherin Alpha's Relationship with SubH2Bv as Acrosome-Associated Proteins in Spermiogenesis

Tran, MONG HOA 04 September 2008 (has links)
Specialized in form and function, the sperm cell is a unique microsystem unto itself where in the cytoskeletal processes and structures of the somatic cell often find new purpose and characteristics within the sperm. Unlike other cells in the human body, this unique cell polarizes and transforms itself from a line of germ cells to evolve into a functional, hydrodynamic haploid spermatozoon. The success of fertilization is dependent on this haploid cell and its specially designed vesicular structure, the acrosome, which provides the leading edge of oocyte penetration. To date, there is little insight into the mechanics of how acrosomic vesicles are successfully targeted and transported to the nuclear envelope and tether to its surface. Our laboratory has identified a novel 15 kDa sperm specific histone variant, SubH2Bv, which possesses a distinct and functional nuclear localization signal (NLS) that associates with the acrosomic vesicle. This study provides evidence that SubH2Bv’s bipartite NLS (an NLS with two basic domains linked together by 10-12 amino acid residues) is responsible for directing acrosomic vesicles to the nuclear envelope using the somatic import receptor, karyopherin alpha (Kap α). Based on bipartite NLS-receptor conventions, where karyopherin alpha is known to specifically associate with this NLS-type, SubH2Bv would be the karyophilic cargo and karyopherin alpha would act as part of the underlying transport mechanism. Western blot analysis and immunohistochemistry characterized Kap α as a membrane-associated sperm protein that is co-localized with SubH2Bv around the proacrosomic granules and the acrosomic vesicle during spermiogenesis. Their co-expression and co-localization, as demonstrated by immunolabelling, suggested a potential binding relationship that was confirmed by a His-tag-recombinant SubH2Bv-pull-down assay. The co-developmental acrosomic expression of Kap α and SubH2Bv in haploid cells, combined with the pull-down evidence of their binding affinity, provides a compelling argument that these two proteins work in concert to traffic the acrosomic vesicles to the nucleus. The exclusion of these two otherwise nuclear proteins from the nucleus, and their co-localization to the subacrosomal region in elongating spermatids, also implies a contingent role for SubH2Bv and Kap α in acrosomal docking, that may involve the classical bipartite/Kap α nuclear import pathway. / Thesis (Master, Anatomy & Cell Biology) -- Queen's University, 2008-09-02 16:11:17.429

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