South Korean strategy for agricultural technology transfer to developing countries

노트 : - Paper prepared for U.S.-Korea Dialogue on Strategies for Effective Development Cooperation - Hosted by the Asia Foundation Korea Center for U.S.-Korea Policy October 17-18, 2011 행사명 : U.S.-Korea Dialogue on Strategies for Effective Development Cooperatio

Singular perturbation analysis of AOTV-related trajectory optimization problems

The problem of real time guidance and optimal control of Aeroassisted Orbit Transfer Vehicles (AOTV's) was addressed using singular perturbation theory as an underlying method of analysis. Trajectories were optimized with the objective of minimum energy expenditure in the atmospheric phase of the maneuver. Two major problem areas were addressed: optimal reentry, and synergetic plane change with aeroglide. For the reentry problem, several reduced order models were analyzed with the objective of optimal changes in heading with minimum energy loss. It was demonstrated that a further model order reduction to a single state model is possible through the application of singular perturbation theory. The optimal solution for the reduced problem defines an optimal altitude profile dependent on the current energy level of the vehicle. A separate boundary layer analysis is used to account for altitude and flight path angle dynamics, and to obtain lift and bank angle control solutions. By considering alternative approximations to solve the boundary layer problem, three guidance laws were derived, each having an analytic feedback form. The guidance laws were evaluated using a Maneuvering Reentry Research Vehicle model and all three laws were found to be near optimal. For the problem of synergetic plane change with aeroglide, a difficult terminal boundary layer control problem arises which to date is found to be analytically intractable. Thus a predictive/corrective solution was developed to satisfy the terminal constraints on altitude and flight path angle. A composite guidance solution was obtained by combining the optimal reentry solution with the predictive/corrective guidance method. Numerical comparisons with the corresponding optimal trajectory solutions show that the resulting performance is very close to optimal. An attempt was made to obtain numerically optimized trajectories for the case where heating rate is constrained. A first order state variable inequality constraint was imposed on the full order AOTV point mass equations of motion, using a simple aerodynamic heating rate model

Effects on the transcriptome upon deletion of a distal element cannot be predicted by the size of the H3K27Ac peak in human cells.

Genome-wide association studies (GWAS) have identified single nucleotide polymorphisms (SNPs) associated with increased risk for colorectal cancer (CRC). A molecular understanding of the functional consequences of this genetic variation is complicated because most GWAS SNPs are located in non-coding regions. We used epigenomic information to identify H3K27Ac peaks in HCT116 colon cancer cells that harbor SNPs associated with an increased risk for CRC. Employing CRISPR/Cas9 nucleases, we deleted a CRC risk-associated H3K27Ac peak from HCT116 cells and observed large-scale changes in gene expression, resulting in decreased expression of many nearby genes. As a comparison, we showed that deletion of a robust H3K27Ac peak not associated with CRC had minimal effects on the transcriptome. Interestingly, although there is no H3K27Ac peak in HEK293 cells in the E7 region, deletion of this region in HEK293 cells decreased expression of several of the same genes that were downregulated in HCT116 cells, including the MYC oncogene. Accordingly, deletion of E7 causes changes in cell culture assays in HCT116 and HEK293 cells. In summary, we show that effects on the transcriptome upon deletion of a distal regulatory element cannot be predicted by the size or presence of an H3K27Ac peak

THE PERSUASION PROCESSES IN VIRTUAL REALITY IN THE CONTEXT OF TECHNOLOGY ACCEPTANCE

This dissertation investigates the extent to which a media audience’s degree of technology acceptance (as a mediator) and interactivity of the media influence the user’s sense of presence, enjoyment, and message engagement, and finally lead to attitude change (persuasion). The study also explores how the user processes a message and changes the individuals’ attitude, guided by the Heuristic-Systematic Model (HSM) of information processing. To test hypotheses, two different types of media as stimuli sorted by levels of stereoscopic dimension (2D screen versus 3D virtual reality) describing a Syrian Refugee crisis were used for an experiment in the study. Stimuli were randomly assigned to 105 university students to 1) watch (screen) or 2) experience (VR). After the experiment, participants were asked to complete a set of questionnaires, which included items to assess the amount of heuristic and systematic processing; the level of presence; message engagement; enjoyment; message-consistent attitude change; and behavioral intention. The results showed VR (high interactivity) induced participants’ higher level of telepresence, social presence, message engagement, and enjoyment than a screen (low interactivity), and finally led to message-consistent attitude and behavioral intention. Heuristic processing was primarily worked in VR, where Systematic processing was mainly shown in the 2D condition. In addition, it was found that Technological Acceptance significantly worked as a mediator between interactivity and message engagement. Limitations and suggestions for future research were discussed with implications for both academic and business field

Non-specific physiological background effects of acupuncture revealed by proteomic analysis in normal rats

BACKGROUND: The total effects of adequate real acupuncture treatment consist of pathologic-specific and non-specific physiological effects. The latter may be the fundamental component of the therapeutic effects of acupuncture. This study investigated the physiological background effects of acupuncture in normal rats treated with acupuncture. METHODS: Manual acupuncture was performed on normal rats at experienced acupoints, GV14 (Dazhui), BL12 (Fengmen) and BL13 (Feishu), once every other day for two weeks. The proteomic profile of rat lung tissue was examined using 2-DE/MS-based proteomic techniques. Gene Ontology (GO) enrichment and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway were analyzed for differentially expressed proteins using the WebGestalt toolkit. RESULTS: In total, 25 differentially expressed protein spots were detected in the 2-DE gels. Among these spots, 24 corresponded to 20 unique proteins that were successfully identified using mass spectrometry. Subsequent GO and KEGG pathway analyses demonstrated that these altered proteins were mainly involved in biological processes, such as ‘protein stabilization’, ‘glycolysis/gluconeogenesis’ and ‘response to stimulus’. CONCLUSIONS: Our study indicated the non-specific background effects of acupuncture at acupoints GV14, BL12 and BL13 likely maintained internal homeostasis via regulation of the local stimulus response, energy metabolism, and biomolecule function balance, which may be important contributors to the therapeutic effects of acupuncture

Modeling, Fabrication and Characterization of Scalable Electroless Gold Plated Nanostructures for Enhanced Surface Plasmon Resonance

The scientific and industrial demand for controllable thin gold (Au) film and Au nanostructures is increasing in many fields including opto-electronics, photovoltaics, MEMS devices, diagnostics, bio-molecular sensors, spectro-/microscopic surfaces and probes. In this study, a novel continuous flow electroless (CF-EL) Au plating method is developed to fabricate uniform Au thin films in ambient condition. The enhanced local mass transfer rate and continuous deposition resulting from CF-EL plating improved physical uniformity of deposited Au films and thermally transformed nanoparticles (NPs). Au films and NPs exhibited improved optical photoluminescence (PL) and surface plasmon resonance (SPR), respectively, relative to batch immersion EL (BI-EL) plating. Suggested mass transfer models of Au mole deposition are consistent with optical feature of CF-EL and BI-EL films. The prototype CF-EL plating system is upgraded an automated scalable CF-EL plating system with real-time transmission UV-vis (T-UV) spectroscopy which provides the advantage of CF-EL plating, such as more uniform surface morphology, and overcomes the disadvantages of conventional EL plating, such as no continuous process and low deposition rate, using continuous process and controllable deposition rate. Throughout this work, dynamic morphological and chemical transitions during redox-driven self-assembly of Ag and Au film on silica surfaces under kinetic and equilibrium conditions are distinguished by correlating real-time T-UV spectroscopy with X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) measurements. The characterization suggests that four previously unrecognized time-dependent physicochemical regimes occur during consecutive EL deposition of silver (Ag) and Au onto tin-sensitized silica surfaces: self-limiting Ag activation; transitory Ag NP formation; transitional Au-Ag alloy formation during galvanic replacement of Ag by Au; and uniform morphology formation under controlled hydraulic conditions. A method to achieve the time-resolved optical profile of EL Au plating was devised and provided a new transitional EL Au film growth model which validated mass transfer model prediction of the deposited thickness of ¡Ü100 nm thin films. As a part of the project, validation of mass transfer model, a spectrophotometric method for quantitative analysis of metal ion is developed that improves the limit of detection comparable to conventional instrumental analysis. The present work suggests that modeling, fabrication and characterization of this novel CF-EL plating method is performed to achieve an ultimate purpose: developing a reliable, inexpensive wet chemical process for controlled metal thin film and nanostructure fabrication

Appearance-Related Messages in YouTube Workout Videos: A Content Analysis

Prior to the COVID-19 pandemic, many individuals exercised in gyms or attended in-person workout classes. As the pandemic led to shutdowns, many turned to online workout programs to maintain activity levels. The purpose of this analysis was to examine the prevalence of appearance-related messages in 297 popular workout videos on YouTube. Among these videos, 64.3% of the main instructors were women. Instructors were likely to promote beauty ideals, as 100% of the instructors had features consistent with cultural beauty ideals (e.g., clear skin, white teeth, straight hair) and 90.3% had thin or athletic bodies. Additionally, 68.4% of the videos were unlikely to portray instructors who did not have visibly toned or athletic body types, and only 10.1% of the videos included an instructor with features not aligned with Western beauty ideals (e.g., stretch marks, scars, less taunt skin, acne). In addition, 54.5% of the videos depicted instructors wearing tight-fitting workout attire to accentuate various features of the body. In terms of body positivity messaging, 40.1% of the videos included comments related to body appreciation and functionality of the body, as well as underlining the importance of body care (36.0%) and preserving inner positivity (30.3%). Also, only a small percentage of videos in the sample included examples of objectification of the body (6.4%). In contrast to the positive messages emphasizing body appreciation and care, 46.5% of the videos encouraged viewers to work out to lose weight, and 4 videos (1.3%) employed strategies to induce shame or guilt around eating or exercise habits. These findings suggest further examination of the influence of appearance-related messages on social media platforms is warranted