• Journal of Chest Surgery
• /
• 제53권6호
• /
• pp.361-367
• /
• 2020

Background: Malignant primary cardiac tumors are extremely rare, but have a poor prognosis. This study evaluated the surgical outcomes of patients with this disease. Methods: Forty patients who underwent surgery for malignant primary cardiac tumors between January 1998 and December 2018 were enrolled. Participants were divided into 3 groups based on resection margins (R0, 14 patients; R1, 11 patients; and R2, 11 patients) and their surgical outcomes were compared. Heart transplantation was performed in 4 patients with unresectable tumors. Results: Early mortality was reported in 2 cases (5%) due to postoperative bleeding and cerebral hemorrhage secondary to brain metastasis. The 1- and 2-year survival rates were 67.5% and 42.5%, respectively. The median survival time of the patients was 20.3 months (range, 9.2-37.6 months). The median survival time was 48.7, 20.3, and 4.8 months in patients with R0, R1, and R2 resections, respectively (p=0.023). Tumor recurrence occurred in 21 patients (61.7%), including 4 cases of local recurrence and 17 cases of distant metastasis. In patients who underwent heart transplantation, the median survival time was 29.5 months, with 3 cases of distant metastasis. Conclusion: Although surgery for malignant primary cardiac tumors has a poor prognosis, complete resection of the tumor may improve surgical outcomes.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권17호
• /
• pp.7535-7540
• /
• 2015

Background: Early initiation of smoking and chewing of diverse forms of tobacco among youth in India is a significant driver for tobacco epidemic in India. Several socio-demographic factors are predictors of tobacco use in populations, especially among youth. Interventions which address these socio-demographic factors can help policy makers to curb new initiations and avert morbidity and mortality due to tobacco use. Objective: To study the various sociodemographic variables associated with tobacco use among youth in India. Materials and Methods: Secondary analysis of data from the Global Adult Tobacco Survey-India 2009-10 for the age group of 15-24 years was performed and predictors of smoking and smokeless tobacco were analyzed using data on occupation, education, and other sociodemographic factors. Results: In India there are a total of 51.3 million (22.1%) youth (15-24 years) tobacco users. Of these 35.1 million consumes chewable tobacco (15.1%), 16.2 million smoke (7%) and 1.6 million are dual users (3.1%). Males, urban, less educated, un-employed and those belonging to middle class preferred smoking over chewing; whereas, females, rural, students and those belonging to low socio-economic class are predictors of smokeless tobacco use. The major determinants of dual users are male sex, poor socio-economic strata and student class. The overall tobacco use was higher among males, rural populations, lower socioeconomic strata and un-employed class. Conclusions: India's youth is more susceptible to the tobacco addiction, especially of smokeless tobacco. Youth from rural India especially students, girls and those from poor socio-economic strata prefer to use smokeless tobacco products whereas urban, male and those less educated prefer smoking tobacco products. More population-based and region-focused research is needed to understand initiation patterns into tobacco use among youth so as to inform policymakers to devise new policy measures to curb the growing epidemic.

• 대한정형외과학회지
• /
• 제56권2호
• /
• pp.117-124
• /
• 2021

비록 수술적 치료의 발전에 의해 부정유합의 발생은 감소하였으나 복합적 골절 또는 동반된 손상 등으로 인하여 드물지 않은 합병증이다. 관절 연골에 과한 하중이나 관절의 불안정성이 예상되는 부정유합이 있다면 교정 절골술이 필요하다. 부정유합에 대한 절골술을 시행하기 위해서는 수술 전 계획이 매우 중요하다. 적절한 계획이 없을 경우 의인성 부정정렬, 수술중 골절, 변형의 재발, 연부조직의 손상과 같은 심각한 합병증이 따르게 된다. 또한 적절한 환자를 선택하지 않았을 경우 불량한 기능적 결과가 나타날 수 있다. 본 종설은 부정유합을 치료하기 위하여 수술적 적응증, 수술 전 계획, 그리고 수술방법과 고정물 종류에 따른 다양한 교정 절골술의 방법에 대하여 기술하였다.

• Plant Resources
• /
• 제3권3호
• /
• pp.163-172
• /
• 2000

We compared microstructural features of the ordered cell and disordered leaves in Citrus junos Sieb. by electron microscopy. In the cell of the ordered leaves, many chloroplasts and large vacuoles were particularly observed. Also a lot of vessel, companion cell and big nucleus were presented in vascular bundle regions. The mitochondria and the other organelles were interspersed among the chloroplasts in a thin, peripheral layer of cytoplasm. The chloroplast possessed typical grana and intergranal lamellae, numerous starch grains and a few small osmophilic globules. Besides, microbodies were closely associated with the mitochondria and the chloroplast. The process of the formation of the secondary cell wall from primary cell wall was observed the vessel elements, the tonoplast wall and the secondary cell wall. It was observed that the oil sac with the unique perfume distributed the adjacent cell wall. In the cell of disordered leaves, the all of the organelles were thrust toward the cell wall due to the fusion of vacuoles in the cells. It was observed that a lot of the very small particles spreaded in the cytoplasm. The loss of unique perfume of the leaves was resulted in the destruction of the oil sac. Also, there was not observed grana, lamellae, starch and osmophillic globules in the chloroplast. The small distributed organelles was not observed but the elongation of the cell wall was proceed no longer. Therefore, the plasma membrane diverged from the cell wall. All of organelles in the cell had poor function and deformation. A massive vacuole was fulfilled in single cell and the vacuole contains a lot of large and small particles. The organelles were presented on the side of the cell wall according to the enlargement of vacuole and they were observed to be breakdown.

• Nuclear Engineering and Technology
• /
• 제40권1호
• /
• pp.49-68
• /
• 2008

The purpose of this paper is to extensively review the condition monitoring (CM) techniques using empirical models in an effort to reduce or eliminate unexpected downtimes in general industry, and to illustrate the feasibility of applying them to the nuclear industry. CM provides on-time warnings of system states to enable the optimal scheduling of maintenance and, ultimately, plant uptime is maximized. Currently, most maintenance processes tend to be either reactive, or part of scheduled, or preventive maintenance. Such maintenance is being increasingly reported as a poor practice for two reasons: first, the component does not necessarily require maintenance, thus the maintenance cost is wasted, and secondly, failure catalysts are introduced into properly working components, which is worse. This paper first summarizes the technical aspects of CM including state estimation and state monitoring. The mathematical background of CM is mature enough even for commercial use in the nuclear industry. Considering the current computational capabilities of CM, its application is not limited by technical difficulties, but by a lack of desire on the part of industry to implement it. For practical applications in the nuclear industry, it may be more important to clarify and quantify the negative impact of unexpected outcomes or failures in CM than it is to investigate its advantages. In other words, while issues regarding accuracy have been targeted to date, the concerns regarding robustness should now be concentrated on. Standardizing the anticipated failures and the possibly harsh operating conditions, and then evaluating the impact of the proposed CM under those conditions may be necessary. In order to make the CM techniques practical for the nuclear industry in the future, it is recommended that a prototype CM system be applied to a secondary system in which most of the components are non-safety grade. Recently, many activities to enhance the safety and efficiency of the secondary system have been encouraged. With the application of CM to nuclear power plants, it is expected to increase profit while addressing safety and economic issues.

• Bulletin of the Korean Chemical Society
• /
• 제31권5호
• /
• pp.1199-1203
• /
• 2010

Second-order rate constants ($k_N$) have been measured spectrophotometrically for Michael-type reactions of 1-(X-substituted phenyl)-2-propyn-1-ones (2a-f) with a series of alicyclic secondary amines in MeCN at $25.0{\pm}0.1^{\circ}C$. The $k_N$ value increases as the incoming amine becomes more basic and the substituent X changes form an electron-donating group (EDG) to an electron-withdrawing group (EWG). The Br${\o}$nsted-type plots are linear with ${\beta}_{nuc}$ = 0.48 - 0.51. The Hammett plots for the reactions of 2a-f exhibit poor correlations but the corresponding Yukawa-Tsuno plots result in much better linear correlations with ${\rho}$ = 1.57 and r = 0.46 for the reactions with piperidine while ${\rho}$ = 1.72 and r = 0.39 for those with morpholine. The amines employed in this study are less reactive in MeCN than in water for reactions with substrates possessing an EDG, although they are ca. 8 pKa units more basic in the aprotic solvent. This indicates that the transition state (TS) is significantly more destabilized than the ground state (GS) in the aprotic solvent. It has been concluded that the reactions proceed through a stepwise mechanism with a partially charged TS, since such TS would be destabilized in the aprotic solvent due to the electronic repulsion between the negative-dipole end of MeCN and the negative charge of the TS. The fact that primary deuterium kinetic effect is absent supports a stepwise mechanism in which proton transfer occurs after the rate-determining step.

• 인간식물환경학회지
• /
• 제24권2호
• /
• pp.195-207
• /
• 2021

Background and objective: While response measures to particulate matters in rural areas are limited due to poor inventory record keeping in the agricultural sector, it is necessary to control agricultural waste vinyl and the emission of precursors released from open burning and the secondary generation of particulate matters. Currently, the open burning emission calculation method uses the definition prescribed in CAPSS by the National Institute of Environmental Research. Methods: This study presented an open burning emission calculation formula for agricultural waste vinyl, which is included as agricultural waste. As for activity data, the open burning ratio of agricultural waste vinyl, and the annual incineration volume provided in the Status Survey by the Ministry of Agriculture, Food, and Rural Affairs were applied. The emission factor was generated through incineration tests on three agricultural plastic film samples collected by the Korea Environment Corporation. Results: Among precursors, SOx and NOx were selected and their emission features were monitored with incineration experiment infrastructure based on the EPA 5G method. The highest emission concentration by agricultural waste type was concentrated in the first and second quarters. As for emission factor of SO₂, it was calculated at 98.25 g/kg for mulching-use LDPE, 52.31 g/kg for greenhouse-use LDPE, and 14.40 g/kg for HDPE. As for NOx, it was calculated at 18.21 g/kg for mulching-use LDPE, 16.49 g/kg for greenhouse-use LDPE, and 10.67 g/kg for HDPE. Conclusion: This test confirmed the incineration features of PE-based plastics, ascertained the SOx emission factor that had not been included in open burning in the past, and established that low NOx emission concentration is interfered by soil mixed with livestock excretions. The findings from this study are expected to contribute to improving the system for controlling air pollutants in rural environments.

• 한국학교ㆍ지역보건교육학회지
• /
• 제18권2호
• /
• pp.1-25
• /
• 2017

Objectives: There is higher rates of experience of suicide ideation and suicide attempt of adolescents in the Lima and Callao region compared with the results of the epidemiological study (2013) conducted by Peru National Institute of Mental Health and the Global School-based Student Health Survey (2010) which is was conducted among adolescents across all regions of Peru. Based on the PRECEDE model, this study analyzed the prevalence and the factor associated with the suicide attempt among the adolescent in a poor urban area in Peru. Methods: A stratified random sampling was used for the survey to select study participants from the 6 secondary schools based in Comas or Callao. The survey was conducted November 25th and December 4th in 2015 and a total of 738 individuals included in the analysis. In order to analyze factors influencing suicide attempt, comparison of predisposing factor, reinforcing factor, enabling factor, behavioral factor, environmental factor, psychological factors by suicide attempt and suicide risk group were identified through the chi-square test and hierarchical logistic regression. Results: Results showed that those who reported having less parental understanding, less time spent with parents, and 'almost none/none' for parental affection had more experience of suicide attempt and were more likely to sort into the high suicide risk group. Also, a greater proportion of those with the experience of suicide attempt had more experience of smoking and alcohol consumption, and experience of physical abuse and feeling insulted and depression in comparison to that of those without experience of suicide attempt. Variables that had a significant effect on suicide attempt included depression, subjective happiness, smoking experience, sexual intercourse, involvement in fight, parental affection, and gender (male). Conclusions: The results of the current study can serve as grounds for the necessity of acknowledging that adolescent suicide does not simply depend on a couple of factors, but arises from situations in which individual, home, school, social factors influence one another, and therefore adolescent suicide should be prevented and addressed through a multi-dimensional and integrated approach.

• 한국수소및신에너지학회논문집
• /
• 제20권6호
• /
• pp.505-511
• /
• 2009

The hydriding and electrochemical characteristics of Zr-based $AB_2$ alloy produced by gas atomization have been extensively examined. For the particle morphology of the as-cast and gas-atomized powders, it can be seen that the mechanically crushed powders are irregular, while the atomized powder particles are spherical. The increase of jet pressure of gas atomization process results in the decrease of hydrogen storage capacity and the slope of plateau pressure significantly increases. TEM and EDS studies showed the increase of jet pressure in the atomization process accelerated the phase separation within grain of the gas-atomized alloy, which brought about a poor hydrogenation property. However, the gas-atomized $AB_2$ alloy powders produced by jet pressure of 50 bar kept up the reversible $H_2$ storage capacity and discharge capacity similar to the mechanically crushed particles. In addition, the electrode of gas-atomized Zr-based $AB_2$ alloy of 50 bar showed improved cyclic stability over that of the cast and crushed particulate, which is attributed to the restriction of crack propagation by grain boundary and dislocation with ch/discharging cycling.

• Safety and Health at Work
• /
• 제5권3호
• /
• pp.140-146
• /
• 2014

Background: Young male and female workers are over-represented in statistics concerning negative outcomes of poor work environment and risky work. Young workers often have low awareness of risk, a lack of safety training, and inadequate introduction to the work. The aim of this study was to identify the knowledge and experiences of pupils of vocational schools concerning potential work environment risks in their future work. Methods: The study design was a dual one, and included a questionnaire and focus group interviews. The study group consisted of 239 pupils from 10 upper secondary schools, who were graduating pupils in four vocational programs: the Industrial Technology Programme, the Restaurant Management and Food Programme, the Transport Programme, and the Handicraft Programme (in which students specialize in wood products). The upper secondary schools were located in the central region of Sweden. Results: The pupils had limited knowledge that employers must, by law, conduct risk analyses and prevent risks. Many felt that they themselves are mainly responsible for performing their tasks safely. Pupils in all programs mentioned acute risk as the greatest risk at work. The theoretical education about safety at work was provided in the $1^{st}$ year of the 3-year vocational programs. Conclusion: A systematic approach to pupils' training in work environment, which is a basis for a safe and healthy workplace, is lacking. The study findings indicate that pupils are offered knowledge far from that intended by laws and by state-of-the-art occupational health risk research.