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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.
301

Cloning and Expression of Arabidopsis endo-1,4-£]-glucanase in Pichia pastoris

Chao, Shih-hsien 05 February 2010 (has links)
In recent years. as industrialized society developed. people have made a lot of environment pollution problems owing to overusing fossil fuel, moreover. fossil fuel is going to deplete. As the result. the study of the substitute energy is promoted. Ligonocellulose (lignin, cellulose and hemicelluloses are included) are the most plentiful renewable resources in the nature, and it have high economic values which extensively use on food, paper and energy. Recent years, it is a hot issue that decomposing cellulose into the minimum unit called glucose, and further, fermenting into alcohol to generate biomass energy. This research goal is cloning Arabidopsis endo-1,4-£]-glucanase and transfer to Escherichia coli(DH5£\). Selection pPICZ£\A the success transferr DNA Fragment. Then to sequence and because of cell in pPICZ£\A have expression in Pichia. pastoris. AOX1 promoter have Mass productions Arabidopsis endo-1,4-£]-glucanase gene in Pichia pastoris. Carries on the extracellular expression by the methyl alcohol induction way. Can obtain recombinant DNA protein. However the Western blotting analysis demonstration has this enzyme active protein At4g11050 pellet Molecular weight about 89 KDa. Again by way of congo red and Dye-CMC assay activeness of the examination enzyme protein. The result discovers At4g11050 in the pellet cell activity compares with negative control has the obvious activity.
302

Self-perceptions of volunteer management:: a texas 4-h volunteer needs assessment

Torock, Jodi Lynn 15 May 2009 (has links)
The purpose of this study was to assess the management of volunteers through self-perceptions of Texas 4-H volunteers. This research was an on-line questionnaire designed to assess volunteers’ attitudes toward recruitment, orientation, training, resources, utilization, motivations for continuation of service, and recognition. The population was volunteers enrolled in the Texas 4-H Program during the 2007-2008 program year. The census included 711 Texas 4-H volunteer respondents. This study used a questionnaire designed by the researcher and a team of faculty and staff at a major land grant university and a demographics questionnaire. SPSS® 16.0 for Windows® was used to analyze the data. The study revealed that most Texas 4-H volunteers are oriented and trained in their roles and responsibilities as a volunteer, have additional opportunities for training in their role as club managers or project leaders, have the resources necessary to fulfill their role, and are recognized for their contributions to the Texas 4-H Program. However, as with any program, there is room for improvement. Respondents indicated a need for curriculum development in volunteer and club management. Additionally, 83% of volunteers began volunteering because they had children or family enrolled in the 4-H program; however, volunteers are motivated to continue to serve as volunteers because they want to help youth and support youth development, the 4-H program, agriculture, and family and community development. Respondents indicated they chose to discontinue serving as a 4-H volunteer due to lack of county Extension staff support, lack of time, children aging out of the program, and burnout. The following recommendations for action were based on the findings and conclusions of this study. Volunteer orientation and training programs should become an integral part of all county 4-H volunteer management programs. Curriculum should be developed in the areas of volunteer and club management. In addition, all volunteers should be recognized for their contributions to the program. Orientation, training, and recognition of 4-H volunteers will provide opportunities for volunteers to build an affiliation for the Texas 4-H program, and in turn, motivate volunteers to continue to serve the 4-H youth development program.
303

Implementation of MPEG-4 Video Encoder/Decoder on Microprocessors

Lee, Yu-jen 14 August 2004 (has links)
Digital image data requires large compression ratio in applications like internet, communication and audio-visual environment. In this thesis, we realize the MPEG-4 codec standard on the ARM9-based platform and improve the execution performance by efficient implementations of the core operations such as Motion Estimation and DCT. In the assembly codes obtained by directly compiling the C codes, there exists a lot of redundant checking which causes a large amount of execution time waste. We rewrite some of the compiled assembly codes to improve the execution efficiency using a variety of techniques such as loop-unrolling and data-type optimization. We also analyze the experimental results using several benchmark video sequences with different modes.
304

Analysis on EAC Application of VRV air-conditioning Systems

Su, Lun 26 June 2006 (has links)
In Green Building Evaluation Indexes, the EAC has been adapted as the central HVAC system energy consumption criteria, has been assigned an energy saving factor£\4 of 0.2, despite of the actual power consumption variations existed among various system. In this study, the PILV values of specific VRV systems were utilized, so that actual energy-saving factor £\4 can be evaluated. Furthermore, being lack of the chilled water distribution system, the weighting of power consumption percentages of a VRV system has also been changed into 0.9 vs. 0.1 for the outdoor and indoor units respectively. The methodology established in this study has been justified by suing the actual VRV projects under commercial operations, which can successfully discriminate different energy efficiencies among various systems.
305

Intestinal microflora induce host defense after burn through Toll-like Receptor 4 signaling in mice

Chang, Wei-Jung 23 January 2007 (has links)
The most abundant microflora is present in the distal parts of gut and the majority of the bacteria are Gram-negative anaerobes. Toll-like receptor 4 (TLR4), one of the ¡§pathogen-recognition molecules¡¨, recognize the lipopolysaccharide (LPS), derived from Gram-negative bacteria. TLR4 recognized the intestinal microflora and triggers the inflammatory responses. Although the effect of intestinal microflora on enhancing host to response the challenge from bacteria has been established, the mechanism has not been well studied. In this study, the relationship between TLR4 expression and the inflammatory response under intestinal microflora depletion was investigated. Mice fed with antibiotics for 4 weeks to delete the intestinal commensals and supplemented with or without LPS to stimulate TLR4 at week 3 were under sham or burn treatment. Results showed that thermal injury intestinal permeability, bacterial translocation to mesenteric lymph nodes, and neutrophil deposition in lung. Also, the activation of NF-£MB, expression of HSP70 and TLR4 were induced in intestinal after thermal injury. Moreover, TLR4 expression was increased in lung and peritoneal cells, ICAM and TNF-£\ expression were increased in peritoneal cells after thermal injury. However, NF-£MB activation, expression of TLR4, ICAM, and HSP70 were decreased in intestinal mucosa of mice with microflora depletion after thermal injury. Microflora depletion also significantly decreased the MPO activity in lung, and the phagocytic activity, the TLR4, ICAM, and TNF-£\ expression of peritoneal cells after thermal injury. Interestingly, LPS supplement reversed the effect of microflora depletion, suggest that intestinal microflora can trigger the host defense through TLR4 signaling pathway in thermal injured mice.
306

µL

Su, Min-Chen 26 July 2000 (has links)
none
307

Personal Mobile Communicator

Zheng, Yao-Jei 23 July 2002 (has links)
Increases in bandwidth and computational speed lead to growing interests in real-time audio and video communication over the Internet. With dramatic increase in wireless access recently, a challenging problem associated with audio and video communication lies in how to cope with packet loss and achieve acceptable video quality at the receiver and utilizing the limited wireless bandwidth efficiently. In this paper, we implement a system, Personal Mobile Communicator, to offer video and audio streaming communication. We employ MPEG-4 and GSM to compress video and audio data. MPEG-4 and GSM provide the standardized technological elements to compress video and audio data. MPEG-4 also takes a number of steps to enable robust transmission of compressed video data over noisy communication channels. We implement error resilience tools for reliable transmission and error concealment technologies to provide better video quality when error occurred. The goal of this paper, we design a communication system that is suitable for communication over wireless channel and offer a verification platform for further research.
308

New Intra and Inter Shape Coding Algorithms for MPEG-4

Bian, Shiu-Hong 09 September 2002 (has links)
In this paper, new intra and inter shape coding algorithms are proposed. The new algorithms are based on chain code. Chain code of an object's contour can be divided into several segments by the smooth contour characteristic. By this property, some techniques can be used for the proposed intra and inter shape coding algorithms. In intra mode, each segment is encoded by specific codes, and the decoding result is lossless. Compared with MPEG-4, M4R, DCC and chain code, the compression ratio is improved. Besides, a new coding scheme is proposed for the inter shape coding. It includes finding break points in a series of chain code, correlation between break points and fine scaling with a tolerant threshold between two similar chain code segments. By detecting the segments, break points can be found. The correlation is performed by computing the curvature difference between break points and contour points. The scaling is a technique for extending or shrinking a segment of chain code. Experimental results show that in the condition of high quality or low bit rate our proposed inter shape coding algorithm obtains better performance than MPEG-4 in compression.
309

Service-learning and leadership life skills: an experimental study

Locke, Barbara Darlene 15 November 2004 (has links)
This study examined the effect of service activities on the development of leadership life skills in youth and if having a reflection component as part of the activity makes a difference. Additionally, the study examined the impact of selected demographics including age, gender, type of service completed monthly and 4-H membership on the development of leadership life skills. Participants in the study were from two samples. One group represented the El Paso National Youth Service Day, the other represented the District 11 4-H Leadership Lab in Brenham, Texas. Participants were randomly assigned to a control (no reflection) or treatment (with reflection) group. Youth participants self rated their leadership life skills using a 33-question post-test only questionnaire. Demographics were reported in nine additional questions. The major findings of the study are as follows: 1) Overall, the participants reported their perceived leadership life skills to be high in four of the five subscales; 2) The inclusion of a reflection component did not significantly affect perceived leadership life skills; 3) Type of service, whether direct or indirect, had a significant impact on perceived leadership life skills; 4) 4-H membership had a significant impact on the Personal Leadership Development subscale.
310

Mechanisms of aryl hydrocarbon receptor and estrogen receptor action in breast cancer cells

Lee, Jeong Eun 12 April 2006 (has links)
In MCF7 and T47D cells cotreated with 1 nM 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) plus 0.1-10 μM 3’,4’-dimethoxy flavone (DMF), there was a concentration-dependent decrease in the TCDD-induced ethoxyresorufin O-deethylase (EROD) activity. Gel mobility shift assays showed that 3’,4’-DMF inhibited TCDD-induced aryl hydrocarbon receptor (AhR) transformation in rat liver cytosol and blocked TCDD-induced formation of the nuclear AhR complex in MCF7 and T47D cells. The antiestrogenic activity of TCDD in estrogen-induced transactivation assays in MCF7 cells was reversed by 3’,4’-DMF, confirming the AhR antagonist activity of this compound in breast cancer cells. Cotreatment of T47D and MCF7 cells with TCDD and 10 μM resveratrol inhibited induction of CYP1A1 mRNA and EROD activity. Resveratrol did not inhibit TCDD-induced AhR transformation and reporter gene activity. Actinomycin D chase experiments in T47D cells showed that the mechanism of inhibition of CYP1A1 mRNA and EROD activity is due to an increased rate of CYP1A1 mRNA degradation, suggesting that resveratrol inhibits CYP1A1 via an AhR-independent post-transcriptional pathway. Vitamin D receptor-interacting protein 150 (DRIP150) coactivated estrogen receptor α (ER α)-mediated transactivation and the response was AF2-dependent in ZR75 breast cancer cells. C-and N-terminal NR-boxes (amino acids 1186-1182 and 73-69, respectively) were not necessary for coactivation of ERα. Analysis of DRIP150 deletion mutants identified a 23 amino acid sequence (811-789) required for coactivation. The 23 amino acid contained two regions at amino acids 789-794 and 795-804 which resembled α-helical motifs identified in Lanuguinosa lipase/histamine N-methyl transferase and hepatocyte nuclear factor 1, respectively. A squelching assay using specific point mutations within each α-helix showed that the NIFSEVRVYN (795-804) region was the critical sequence required for the coactivator activity of DRIP150.

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