Comparison of DNS and Reynolds stress modelling of flow around a rotating cylinder

Klaus Bremhorst,Matthew Brennan2,양경수 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.3

The low Reynolds number stress-omega model is applied to flow associated with a rotating cylinder operating in a larger, stationarycylinder. The working fluid fills the gap between the cylinders. Direct numerical simulation data are used to test the predictions by thisturbulence model. Previous work has shown that simpler models are unable to predict with reasonable accuracy the wall shear stressexperienced by the rotating cylinder. The present study with a more complex turbulence model shows that the wall shear stress on therotating cylinder is underestimated significantly. Examination of turbulence velocity fluctuation intensity distributions points to underpredictionof the streamwise turbulence level and excessive values of the wall normal turbulence level. Results are given for no shear anda wall shear at the outer cylinder surface but no effect on the inner cylinder statistics was found. An examination of the Reynolds stressanisotropy tensor components highlights a significant deficiency in this parameter which is an essential component of the pressure-strainmodelling of Reynolds stress models. The most significant aspect is a rapid decrease of the streamwise component of the Reynolds stressanisotropy tensor relative to the direct numerical simulation results and values which are too low for the other two components.

Review : Patient-Reported Outcomes in Gastroenterology; Clinical and Research Applications

( Brennan M R Spiegel ) 대한소화기기능성질환·운동학회(구 대한소화관운동학회) 2013 Journal of Neurogastroenterology and Motility (JNM Vol.19 No.2

Patient-generated reports, also known as Patient-Reported Outcomes (PROs), capture the patients` illness experience in a structured format and may help bridge the gap between patients and providers. PROs measure any aspect of patient-reported health (e.g., physical, emotional or social symptoms) and can help to direct care and improve clinical outcomes. When clinicians systematically collect patient-reported data in the right place at the right time, PRO measurement can effectively aid in detection and management of conditions, improve satisfaction with care and enhance the patient-provider relationship. This review article summarizes the latest approaches to PRO measuring for clinical trials and clinical practice, with a focus on use of PROs in gastroenterology.

A Neutravidin-based Assay for Reverse Transcriptase Suitable for High Throughput Screening of Retroviral Activity

Brennan, Lyndall E.,Sune, Carlos,Klimkait, Thomas 생화학분자생물학회 2002 Journal of biochemistry and molecular biology Vol.35 No.3

A non-isotopic neutravidin-based reverse transcriptase (RT) assay adapted for high throughput screening of HIV activity is described. Using a 96-well microtitre plate, HIV particles are lysed and the RT enzyme released into a reaction mixture containing poly(A) RNA, biotinylated oligo d(T) and fluorescein-labelled dUTP (FI-dUTP). With poly(A) as a template and oligo d(T) as primer, the viron RT incorporates FI-dUTP into an elongating DNA strand. The resulting product is captured on a neutravidin-coated 96-well plate and the unincorporated nucleotides removed by a series of washing steps. A simple ELISA is subsequently performed using a monoclonal antifluorescein antibody conjugated to alkaline phosphatase. Quantification of RT activity is facilitated by a colorimetric readout. The assay was validated in the context of a diagnostic HIV-1 phenotyping assay. Using supernatants from HIV-1 infected lymphocyte cultures the assay was shown to be as sensitive as a radioactive assay and the RT activity correlated well with levels of cell-asociated HIV-p24. Importantly, even minor reductions of RT activity by virus variants with reduced fitness could be distinguished.

An Analysis of the Amihud Illiquidity Premium

Michael Brennan,Sahn-Wook Huh,Avanidhar Subrahmanyam 한국재무학회 2012 한국재무학회 학술대회 Vol.2012 No.05

This paper analyzes the Amihud (2002) measure of illiquidity and its role in assetpricing. It is shown first that the effect of illiquidity on asset pricing is clarified by using the turnover version of the Amihud measure and including firm size as a separate variable. When we decompose the Amihud measure into elements that correspond to positive (up) and negative (down) return days, we find that in general, only the down-day element commands a return premium. Further analysis of the upand down-day elements using order flows shows that a sidedness variable, which captures the tendency for orders to cluster on the sell side on down days, is associated with a more significant return premium than the other components of the Amihud measure.

A Neutravidin - based Assay for Reverse Transcriptase Suitable for High Throughput Screening of Retroviral Activity

(Lyndall E. Brennan),(Carlos Sune),(Thomas Klimkait) 생화학분자생물학회 2002 BMB Reports Vol.35 No.3

A non-isotopic neutravidin-based reverse transcriptase (RT) assay adapted for high throughput screening of HIV activity is described. Using a 96-well microtitre plate, HIV particles are lysed and the RT enzyme released into a reaction mixture containing poly(A) RNA, biotinylated oligo d(T) and fluorescein-labelled dUTP (FI-dUTP). With poly(A) as a template and oligo d(T) as primer, the viron RT incorporates FI-dUTP into an elongating DNA strand. The resulting product is captured on a neutravidin-coated 96-well plate and the unincorporated nucleotides removed by a series of washing steps. A simple ELISA is subsequently performed using a monoclonal antifluorescein antibody conjugated to alkaline phosphatase. Quantification of RT activity is facilitated by a colorimetric readout. The assay was validated in the context of a diagnostic HIV-1 phenotyping assay. Using supernatants from HIV-1 infected lymphocyte cultures the assay was shown to be as sensitive as a radioactive assay and the RT activity correlated well with levels of cell-asociated HIVp24. Importantly, even minor reductions of RT activity by virus variants with reduced fitness could be distinguished.

Bitter Melon (Momordica charantia) Extract Suppresses Adrenocortical Cancer Cell Proliferation Through Modulation of the Apoptotic Pathway, Steroidogenesis, and Insulin-Like Growth Factor Type 1 Receptor/ RAC-a Serine/Threonine-Protein Kinase Signaling

Victoria C. Brennan,Chiung-Min Wang,Wei-Hsiung Yang 한국식품영양과학회 2012 Journal of medicinal food Vol.15 No.4

Adrenocortical carcinomas are rare but present with extremely poor prognosis. One of the approaches to control cancer progression and reduce cancer risk is prevention through diet. Bitter melon is widely consumed as a vegetable and especially as a traditional medicine in many countries. In this study, we have used human and mouse adrenocortical cancer cells as an in vitro model to assess the efficacy of bitter melon extract (BME) as an anticancer agent. The protein concentrations of BME and other extracts were measured before use. First, BME treatment of adrenocortical cancer cells resulted in a significantly dose-dependent decrease in cell proliferation. However, we did not observe an antiproliferative effect in adrenocortical cancer cells treated with extracts from blueberry, zucchini, and acorn squash. Second, apoptosis of adrenocortical cancer cells was accompanied by increased caspase-3 activation and poly(ADP-ribose) polymerase cleavage. BME treatment enhanced cellular tumor antigen p53, cyclin-dependent kinase inhibitor 1A (also called p21), and cyclic AMP–dependent transcription factor-3 levels and inhibited G1/S-specific cyclin D1, D2, and D3, and mitogen-activated protein kinase 8 (also called Janus kinase) expression, suggesting an additional mechanism involving cell cycle regulation and cell survival. Third, BME treatment decreased the key proteins involved in steroidogenesis in adrenocortical cancer cells. BME treatment decreased the level of phosphorylation of cyclin-dependent kinase 7, which is required, at least in part, for steroidogenic factor 1 activation. Finally, we observed that BME treatment significantly reduced the level of insulin-like growth factor 1 receptor and its downstream signaling pathway as evidenced by lower levels of phosphorylated RAC-a serine/threonine-protein kinase. Taken together, these data illustrate the inhibitory effect of bitter melon on cell proliferation of adrenocortical cancer through modulation of diverse mechanisms.

A Convergence of Mobile Device Application Use and Smart Tourism: A Comparison of Korean and Non-Korean Smart Tourists

Bradley S. Brennan 한국인터넷전자상거래학회 2020 인터넷전자상거래연구 Vol.20 No.4

This paper aims to identify mobile device(smartphone) application(apps) usage by Korean and non-Korean tourists within South Korea(Korea); to classify these applications into a taxonomy of mobile device apps used by tourists; to better understand how these tourists utilize these apps while traveling; and to gain insight that can create actionable recommendations for which destinations can use to increase tourist satisfaction. A qualitative methodology approach was used for this paper; consisting of an online electronic survey instrument which asked open-ended questions on which mobile device applications were used. Those results were counted, coded, and then sorted; providing actionable insights to increase tourist satisfaction in pre-departure destination research, online purchases of transportation, accommodation, and entertainment, and tourism spending. Furthermore, valuable tourist trends were identified which could be utilized for eCommerce, smart tourism destinations, and destination marketing organizations(DMOs) to increase tourist satisfaction. A key finding included a significant increase in the use of Korean domestically created apps such as Naver (maps, navigation, transactional, and information), Kakao(maps, social, navigation, communication, taxi, banking, and entertainment), and several other Korean branded apps used by both Korean and non-Korean tourists. Another key finding showed that Koreans are using Facebook and Twitter less and, conversely, Instagram, YouTube, and TikTok, more than before. Therefore, smart destinations and cities must engage and embrace smart tourists on these platforms to promote their destinations to increase tourist satisfaction and intention to revisit and promote Korea as a travel destination.

Online Marketing and Electronic Commerce Integration: A Case Study Examining an International Wine Festival

Bradley S. Brennan,Luo Yiheng,Hyeonu Song 한국인터넷전자상거래학회 2020 인터넷전자상거래연구 Vol.20 No.2

Festival and event attendees are continually seeking unique, authentic, experientially-oriented festivals and events with a greater focus on attendees actively participating in the experience. Festival attendees are seeking more significant personal, meaningful opportunities to participate in wine related activities at wine festivals, but festivals have not capitalized on the sales potential of electronic commerce (e-commerce) post-festival. Examination of a wine festival in South Korea and how through better targeted online marketing - utilizing e-commerce platforms, such as social media, websites and electronic communications (e-communications) - they could significantly increase festival revenue for organizers/vendors while also giving higher attendee satisfaction. An interpretive design approach assisted in obtaining an in-depth understanding of resident, tourist, supplier, non-profit, and local government perspectives. It was then interpreted through an event management and social media marketing perspective. Examining the textual data generated through 24 interviews of festival attendees and suppliers/organizers revealed multiple emergent themes that greatly influenced the attendee’s holistic festival experiences as well as essential insights on how to improve future CIWFs with regards to the event’s online social media marketing, tourism planning, and e-commerce sales post-festival. Findings included festival attendee satisfaction was most realized from entertainment and wine-related activities, desired more wine product information, product education, and product purchasing opportunities. Recommendations will help to improve future CIWF attendance levels, greatly improve revenue generation, and festival management aspects through a multitude of specific, actionable festival management and online marketing activities and initiatives for improved festival attendee satisfaction.

Smart Tourism: A Study of Mobile Application Use by Tourists Visiting South Korea

Bradley S. Brennan,Chul mo Koo,Kyung Mi Bae 인문사회과학기술융합학회 2018 예술인문사회융합멀티미디어논문지 Vol.8 No.10

The purpose of this exploratory study is to identify the mobile phone applications (apps) used by foreign tourists visiting South Korea through a pilot study using focus groups and individual interviews. Concentrating on tourist mobile app use in a smart tourism environment and categorized through a taxonomy of mobile applications lays the framework and determines the factors boosting tourism smartphone app trends by foreign tourists visiting South Korea. Researchers collected data through ethnographic methods and analyzed it through qualitative research to uncover major themes within the smart tourism app use phenomenon. The researchers coded, counted, analyzed, and then divided the findings gleaned from a pilot study and interviews into a taxonomy of seven logical smartphone app categories. The labeling and coding of all the data accounting for similarities and differences can be recognized and are logically discussed in the implications of the apps used by tourists to assist tourist destinations. More specifically these findings will assist smart tourism destinations by better understanding foreign tourist smartphone app use behavior. Tourists visiting South Korea interviewed in this study exhibited significant mastery of Internet of Things (IoT) technologies, craved free WiFi access, and utilized smartphone apps for all facets of their travel. Findings show major concentrations of app use in bookings of accommodations, tourist attractions, online shopping, navigation, wayfinding, augmented reality, information searching, language translation, gaming, and online dating while traveling in South Korea.

Examining the 1st Cheongna International Wine Festival: An Experience Economy Approach

Bradley S. Brennan,구철모 한국인터넷전자상거래학회 2019 인터넷전자상거래연구 Vol.19 No.5

Festival guests are seeking uniquely authentic, experientially-oriented festivals and events with more meaningful opportunities to participate in activities. They simultaneously seek to satisfy desire for education, escaping, and entertainment in esthetically (4E model) desirable locations. The four previously mentioned dimensions or 4E’s form the basis of the “experience economy” theory and subsequent model, as proposed by Gilmore and Pine (1999). The 1st Cheongna International City Wine Festival (CIWF) in South Korea was examined through an interpretive approach to gain an in-depth understanding of the CIWF guests’ experience. Examining the data revealed multiple themes that influenced the overall festival experience where highest satisfaction was obtained from entertainment and wine-related activities. Findings include implications and recommendations for improving the CIWF’s event activities through the 4E realms for greater festival guest satisfaction and to ensure more prosperous future wine festivals.