A photonic-crystal optical antenna for extremely large local-field enhancement

We propose a novel design of an all-dielectric optical antenna based on photonic-band-gap confinement. Specifically, we have engineered the photonic-crystal dipole mode to have broad spectral response (Q ~70) and well-directed vertical-radiation by introducing a plane mirror below the cavity. Considerably large local electric-field intensity enhancement ~4,500 is expected from the proposed design for a normally incident planewave. Furthermore, an analytic model developed based on coupled-mode theory predicts that the electric-field intensity enhancement can easily be over 100,000 by employing reasonably high-Q (~10,000) resonators

ZnO:B back reflector with high haze and low absorption enhanced triple-junction thin film Si solar modules

AbstractWe present our development of a ZnO:B back reflector (BR) with high haze and low absorption for highly efficient triple-junction thin film Si solar modules over a large area (1.1×1.3m2). We try to maximize light trapping by the evaluation of the use of transparent conducting oxide (TCO) and BR for high efficiency. It was verified that the configuration of SnO2:F front TCO and ZnO:B BR shows better optical properties than typical configurations for light trapping due to its high transparency at the front and high haze at the back. In addition, we noticed that the absorption of the BR has a strong influence on the solar modules. We obtained a superior ZnO:B BR with high haze and low absorption by controlling the doping gas ratio (B2H6/DEZ). As the doping gas ratio of ZnO:B BR decreases, the haze increases due to a rougher surface morphology, and the absorption decreases due to reduced free carrier absorption. The solar modules with a ZnO:B BR in a lower doping gas ratio show relatively higher Pmax for the same i-μc-Si layer thickness. This results from an increased Isc due to higher haze and lower absorption. In addition, the ZnO:B BR with a low doping gas ratio was found to be effective in reducing the i-μc-Si layer thickness because there are more chances for trapping the light at the i-μc-Si layer. We could reduce the i-μc-Si layer thickness by about 28% for the equivalent Pmax level by lowering the doping gas ratio. We successfully applied the ZnO:B BR with high haze and low absorption into a triple-junction thin film silicon solar cell and achieved a new record, improving on our previous world record

Entrepreneurial orientation, entrepreneurial education and performance

Purpose - Korean economy is demanding to change from an industrial society to an entrepreneurial society. It is asking for a generational change from the preexisting paradigms of such as labor consciousness, the concept of work and company management. Entrepreneurship is one of the key elements that will lead to a successful business performance under highly uncertain business conditions. The purpose of this paper is to examine the relationship between entrepreneurial orientation and business performance. Also, the authors look for the role of entrepreneurship education in the influence of entrepreneurial orientation on financial and nonfinancial business performance. Design/methodology/approach - To accomplish the purpose of this study, the authors carried out a survey targeting nascent entrepreneurs and total early-stage entrepreneurs with less than seven years of experience. Based on the Miller’s (1983) definition, a group of questions for entrepreneurial orientation, similar to Covin and Slevin (1989), were developed. Findings - First, among the subfactors of entrepreneurial orientation, it was clear that innovative progressiveness affected nonfinancial business performance. Second, risk-taking propensity did not influence both financial business performance and nonfinancial business performance. Third, entrepreneurship education had no connection with entrepreneurial orientation or business performance. Practical implications - Nonfinancial business performances are related with long-term goals and growth potential. Innovative proactiveness affects nonfinancial business performance. Thus, entrepreneurs should look for ways to promote their innovative proactiveness. Entrepreneurship education for experienced entrepreneurs is not as effective as that for students. Originality/value - In the authors’ study, survey questionnaires were sent to 200 nascent and total early-stage entrepreneurs searching for business angel investments or entrepreneurship consultants in Korea. A total of 180 entrepreneurs answered the survey questions online. There are not so many valid studies examining the effect of entrepreneurship education for nascent and total early-stage entrepreneurs in Korea

Immunogenicity and safety of an AS03-adjuvanted H5N1 pandemic influenza vaccine in Korean adults: A phase IV, randomized, open-label, controlled study

AbstractBackgroundAS03-adjuvanted H5N1 pandemic influenza vaccines have been assessed in an extensive clinical development program conducted in North America, Europe, and Asia including children from 6 months of age, adults, and elderly adults. We evaluated AS03-H5N1 in Korean adults 18 through 60 years of age.MethodsThis Phase IV, randomized, study was conducted to assess the immunogenicity, reactogenicity, and safety of two doses (3.75μg of hemagglutinin antigen) of A/Indonesia/5/2005 (H5N1) adjuvanted with AS03 given 21 days apart in Korean adults. Antibody responses were assessed using hemagglutination-inhibition (HI) assays against the vaccine strain and a vaccine-heterologous strain (A/Vietnam/1194/2004) 21 days after the second dose. A control group (safety) received a licensed seasonal inactivated trivalent influenza vaccine (TIV). Reactogenicity was assessed for 7 days after each vaccination, and unsolicited adverse events were assessed for 182 days following vaccination in both study groups (NCT01730378).ResultsAS03-H5N1 was immunogenic and elicited robust HI antibody responses with seroconversion rates of 100% for the vaccine strain and 69.1% for the heterologous strain (N=81). HI antibody responses fulfilled the European licensure criteria for immunogenicity (primary endpoint). The incidence of local and systemic solicited adverse events (reactogenicity) was higher with AS03-H5N1 than TIV. There was no apparent difference in the rate of unsolicited adverse events in the AS03-H5N1 and TIV groups.ConclusionThe results indicate that AS03-H5N1 vaccine is immunogenic with reactogenicity and safety findings that are consistent with the established profile of AS03-H5N1 vaccine

Development of thermal switch using liquid column

Paper presented at the 6th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 30 June - 2 July, 2008.This paper presents the thermal switch which is composed of several switching channels, breathing grooves, reservoirs and actuators to control the liquid column. In the “on” state, a switching channel is filled with liquid supplied by an actuator, which decreases the thermal resistance. In the “off” state, the air fills in the gap of two plates instead of the liquid column and the thermal resistance is increased. Through this switch operation, temperature of the designated hot spot can be controlled locally. In order to realize the desired switch operation, the liquid column should be precisely controlled based on channel design. The switching channel is composed of burst area and path area to achieve the smooth operation. The burst area was geometrically designed to provide the hydrophilic surface geometrically by taking into account of burst area. Experiments were performed on a designed switch for the liquid column control and the heat flow regulation. The results showed that this thermal switch is able to make the “on” and “off” state by controlling liquid column well. Also, the temperature distribution and thermal resistance has been changed according to channel state.vk201

Epigenomic analysis reveals prevalent contribution of transposable elements to cis-regulatory elements, tissue-specific expression, and alternative promoters in zebrafish

Transposable elements (TEs) encode regulatory elements that impact gene expression in multiple species, yet a comprehensive analysis of zebrafish TEs in the context of gene regulation is lacking. Here, we systematically investigate the epigenomic and transcriptomic landscape of TEs across 11 adult zebrafish tissues using multidimensional sequencing data. We find that TEs contribute substantially to a diverse array of regulatory elements in the zebrafish genome and that 37% of TEs are positioned in active regulatory states in adult zebrafish tissues. We identify TE subfamilies enriched in highly specific regulatory elements among different tissues. We use transcript assembly to discover TE-derived transcriptional units expressed across tissues. Finally, we show that novel TE-derived promoters can initiate tissue-specific transcription of alternate gene isoforms. This work provides a comprehensive profile of TE activity across normal zebrafish tissues, shedding light on mechanisms underlying the regulation of gene expression in this widely used model organism

Optic Nerve Injury Secondary to Endoscopic Sinus Surgery: an Analysis of Three Cases

Major orbital complications after the endoscopic sinus surgeries are rare and of these, optic nerve injury is one of the most serious. This study was to undertaken to analyze 3 cases of optic nerve injury after endoscopic sinus surgery. The three cases included one patient with a loss of visual acuity and visual field defect, and two patients with total blindness. In all cases, no improvement of visual acuity was observed despite treatment. It is important to frequently check the location and direction of the endoscope during surgery to avoid optic nerve injury. In addition, surgeons must have a precise knowledge of the detailed anatomy through cadaver dissections, an ability to interpret the PNS CT scan and experienced procedural surgical skills

β-Lapachone Significantly Increases the Effect of Ionizing Radiation to Cause Mitochondrial Apoptosis via JNK Activation in Cancer Cells

β-lapachone (β-lap), has been known to cause NQO1-dependnet death in cancer cells and sensitize cancer cells to ionizing radiation (IR). We investigated the mechanisms underlying the radiosensitization caused by β-lap. cells induced ROS generation, triggered ER stress and stimulated activation of ERK and JNK. Inhibition of ROS generation by NAC effectively attenuated the activation of ERK and JNK, induction of ER stress, and subsequent apoptosis. Importantly, inhibition of ERK abolished ROS generation and ER stress, whereas inhibition of JNK did not, indicating that positive feedback regulation between ERK activation and ROS generation triggers ER stress in response to combined treatment. Furthermore, prevention of ER stress completely blocked combination treatment-induced JNK activation and subsequent apoptotic cell death. In addition, combined treatment efficiently induced the mitochondrial translocation of cleaved Bax, disrupted mitochondrial membrane potential, and the nuclear translocation of AIF, all of which were efficiently blocked by a JNK inhibitor. Caspases 3, 8 and 9 were activated by combined treatment but inhibition of these caspases did not abolish apoptosis indicating caspase activation played a minor role in the induction of apoptosis. cells are treated with combination of IR and β-lap, positive feedback regulation between ERK and ROS leads to ER stress causing JNK activation and mitochondrial translocation of cleaved Bax. The resultant decrease in mitochondrial membrane leads to translocation of AIF and apoptosis