Metastatic carcinoma of the oral region : an analysis of 21 cases

Metastatic carcinoma to the jaws and oral region are very rare, representing less than 1% of all oral tumors. Unfortunately, oral metastasis is usually manifestation of an advanced stage of primary cancer, and indicates widespread disease and poor prognosis. In this retrospective study, a total of 2039 patients with history of oral malignant tumor between 1980 and 2012 at Seoul National University Dental Hospital were evaluated. We analyzed the dental and medical records, and histopathological database of 2039 patients to assess the prevalence of oral metastasis of carcinoma in terms of sex and age, as well as, the most common origin of primary cancer, and prevalent site and histopathological type of metastatic carcinoma. Among 2039 patients, 21 (1.03%) were finally diagnosed with metastatic carcinoma of the jaws and oral region. Among the 21 patients, only 11 had a working diagnosis as oral metastasis upon clinical evaluation before performing a biopsy. The mean age at the time of diagnosis with a metastatic carcinoma was 56.86, and there was a male preponderance. Metastatic carcinoma was more frequent in the jaws than in the soft tissue, especially in the mandible compared to the maxilla. The most frequent primary site was the lungs, followed by the liver and breasts. The predominant histopathological types were hepatocellular carcinoma and adenocarcinoma. Patient outcomes indicated a poor prognosis with the time from the appearance of the metastasis to death was only 12 months. According to these cases, oral metastases of carcinoma were exceedingly rare in Koreans. It can allow the clinicians take into account the possible presence of metastases and lead to early diagnosis

Collapse transition of a square-lattice polymer with next nearest-neighbor interaction

We study the collapse transition of a polymer on a square lattice with both nearest-neighbor and next nearest-neighbor interactions, by calculating the exact partition function zeros up to chain length 36. The transition behavior is much more pronounced than that of the model with nearest-neighbor interactions only. The crossover exponent and the transition temperature are estimated from the scaling behavior of the first zeros with increasing chain length. The results suggest that the model is of the same universality class as the usual theta point described by the model with only nearest-neighbor interaction.Comment: 14 pages, 5 figure

TED Talk Recommender Using Speech Transcripts

Nowadays, online video platforms mostly recommend related videos by analyzing user-driven data such as viewing patterns, rather than the content of the videos. However, content is more important than any other element when videos aim to deliver knowledge. Therefore, we have developed a web application which recommends related TED lecture videos to the users, considering the content of the videos from the transcripts. TED Talk Recommender constructs a network for recommending videos that are similar content-wise and providing a user interface.Comment: 3 page

Technical Efficiency in the Iron and Steel Industry: A Stochastic Frontier Approach

In this paper we examine the technical efficiency of firms in the iron and steel industry and try to identify the factors contributing to the industry's efficiency growth, using a time-varying stochastic frontier model. Based on our findings, which pertain to 52 iron and steel firms over the period of 1978-1997, POSCO and Nippon Steel were the most efficient firms, with their production, on average, exceeding 95 percent of their potential output. Our findings also shed light on possible sources of efficiency growth in the industry. If a firm is government-owned, its privatization is likely to improve its technical efficiency to a great extent. A firm's technical efficiency also tends to be positively related to its production level as measured by a share of the total world production of crude steel. Another important source of efficiency growth identified by our empirical findings is adoption of new technologies and equipment. Our findings clearly indicate that continued efforts to update technologies and equipment are critical in pursuit of efficiency in the iron and steel industry.

Effects of emotional labor on musculoskeletal disorders among physical therapists in Seoul

Introduction: Health care workers, including physical therapists, have some of the most important roles in the health care system as shown during the COVID-19 pandemic. Physical therapists encounter emotionally and physically vulnerable patients, experience emotional labor, and are exposed to conditions that can lead to job stress and musculoskeletal disorders. We aimed to examine the relationship between physical therapists’ emotional labor and its effect on perceived job stress and risk of musculoskeletal disorders. Methods: We conducted a 30-day survey among 230 physical therapists working in various settings from October 2 to November 1, 2019. Questionnaires, including questions on musculoskeletal symptoms, perceived job stress, and emotional labor, were administered to the participants. Results: The physical therapist's surface behavior affected the body burden. Job burnout experienced by physical therapists had an effect on their interpersonal relationships. The physical therapist's emotional law affects the degree of compensation. Conclusion: To prevent the long-term consequences of work-related strain, physical therapists should receive support in terms of maintaining a healthy lifestyle and developing effective methods of communication with patients. Encouragement of activities for psychological rejuvenation with colleagues with whom they can share emotional difficulties is also desirable. It is also necessary to establish a communication channel that can directly convey the grievances of physical therapists to hospitals

k-Space Deep Learning for Reference-free EPI Ghost Correction

Nyquist ghost artifacts in EPI are originated from phase mismatch between the even and odd echoes. However, conventional correction methods using reference scans often produce erroneous results especially in high-field MRI due to the non-linear and time-varying local magnetic field changes. Recently, it was shown that the problem of ghost correction can be reformulated as k-space interpolation problem that can be solved using structured low-rank Hankel matrix approaches. Another recent work showed that data driven Hankel matrix decomposition can be reformulated to exhibit similar structures as deep convolutional neural network. By synergistically combining these findings, we propose a k-space deep learning approach that immediately corrects the phase mismatch without a reference scan in both accelerated and non-accelerated EPI acquisitions. To take advantage of the even and odd-phase directional redundancy, the k-space data is divided into two channels configured with even and odd phase encodings. The redundancies between coils are also exploited by stacking the multi-coil k-space data into additional input channels. Then, our k-space ghost correction network is trained to learn the interpolation kernel to estimate the missing virtual k-space data. For the accelerated EPI data, the same neural network is trained to directly estimate the interpolation kernels for missing k-space data from both ghost and subsampling. Reconstruction results using 3T and 7T in-vivo data showed that the proposed method outperformed the image quality compared to the existing methods, and the computing time is much faster.The proposed k-space deep learning for EPI ghost correction is highly robust and fast, and can be combined with acceleration, so that it can be used as a promising correction tool for high-field MRI without changing the current acquisition protocol.Comment: To appear in Magnetic Resonance in Medicin

The sociocultural environment, maternal employment status and Korean children's awareness of sex-trait stereotypes

The awareness of sex-trait stereotypes among 120, eight-year-old children from intact families in both rural and urban areas in Korea were investigated. The rural sample included 20 boys and 20 girls attending the Damyang-Dong Primary School in Damyang-Eup, Korea. These subjects came primarily from farm families of the upper-lower and lower-middle classes. The urban sample included 40 boys and 40 girls attending the Bokwang Primary School in a residential area of Seoul, the capital city of Korea. These subjects came from families of the lower-middle and upper-middle classes. Twenty boys and 20 girls in the urban sample had mothers who were employed on a full-time basis outside of the home for one year or more. The remaining 20 boys and 20 girls had mothers who were not employed. The Sex Stereotype Measure II (SSM II) was translated into Korean and used to assess subjects' awareness of sex-trait stereotypes. Results revealed that eight-year-old Korean children were aware of the sex-trait stereotypes found in the SSM II. Their scores were comparable to the mean sex - trait stereotype scores of similar aged children in the United States, England, and Ireland. In addition, urban children were significantly more aware of the sex-trait stereotypes than rural children. No significant difference was found between the awareness of sex-trait stereotypes among children whose mothers were employed and those whose mothers were not employed. Children were significantly more aware of the male- than the female-trait stereotypes. Furthermore, while boys were significantly more aware of the male- than female-trait stereotypes, there was no significant difference between girls' awareness of these sex-trait stereotypes. Findings were discussed on the basis of previous theory and research

Developmental aspects of the awareness of sex-trait stereotypes among Korean children

A Korean Sex Stereotype Measure (KSSM) was developed to assess the awareness of sex-trait stereotypes among Korean children. The KSSM contains 32 descriptions of psychological characteristics, 16 of which represent the male-trait stereotypes, and 16 of which represent the female-trait stereotypes. In a test situation, subjects were asked to associate the sex-trait stereotypes with either a male, female or "both" a male and a female silhouette figure drawing. Reliability assessments, including internal consistency and stability estimates, indicated the KSSM to be a highly reliable instrument, particularly among third- and sixth-grade Korean children. The KSSM was applied to 130 first-, third-, and sixth-grade Korean boys and girls, using four different scoring procedures. These scoring procedures represented different concepts of sex roles identified as (1) sex-trait awareness-cultural, (2) sex-trait stereotyping-association, (3) sex-trait awareness-egalitarian, and (4) sex-trait awareness-confirmation. The following general results were obtained when considering all scoring procedures together. Korean children's awareness of the sex-trait stereotypes increased with age from the first- to the sixth-grades. In addition, these children were more aware, and sex-typed more male- than female-traits. Furthermore, while boys were more aware, and sex-typed more male- than female-traits, there were no differences between girls' awareness and sex-typing of male- and female-traits. Finally, sixth-grade children appeared to sex-type more opposite sex-traits as appropriate for "both" males and females than their own sex-traits. Findings were interpreted on the basis of previous theory and research. Discussion also occurred regarding the advantages and disadvantages of using the different scoring procedures in assessing children's awareness of the sex-trait stereotypes. Emphasis was placed on the importance of understanding the concept of sex role being assessed when using these different scoring procedures. Although certain findings were obtained which cut across different scoring procedures, other results obtained appeared to be characteristic of a particular scoring procedure. Therefore, future studies might wish to further clarify the conceptual differences between these scoring procedures in assessing children's awareness of the sex-trait stereotypes

Epidemiology of Foodborne Norovirus Outbreak in Incheon, Korea

On June 14, 2008, an outbreak of gastroenteritis occurred among elementary school students in Incheon. We conducted an investigation to identify the source and described the extent of the outbreak. We performed a retrospective cohort study among students, teachers and food handlers exposed to canteen food in the elementary school. Using self-administered questionnaires we collected information on symptoms, days of canteen food eaten, food items consumed. Stool samples were collected from 131 symptomatic people and 11 food handlers. The catering kitchen was inspected and food samples were taken. Of the 1,560 people who ate canteen food, 117 were symptomatic cases, and the attack rate was 7.5%. Consumption of cucumber-crown daisy salad (RR=2.71), fresh cabbage mix (RR=2.23), dried radish salad (RR=3.04) and young radish kimchi (RR=2.52) were associated with illness. Sixty-four (45%) of the 142 stool specimens were positive for Norovirus. Norovirus was detected in 2 food handlers. Interviews with kitchen staff indicated the likelihood of contamination from an infected food handler to the dried radish salad during food processing. The excretion of Norovirus from asymptomatic food handlers may be an infection source of Norovirus outbreaks