• Journal of the Korean Society for Nondestructive Testing
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• v.18 no.5
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• pp.373-380
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• 1998

The prediction of bone strength by ultrasound velocity and broadband ultrasound attenuation was examined. Ultrasound velocity and broadband attenuation were measured for sixty specimens of human trabecular bone. Samples were divided into two equal groups and loaded in compression at the strain rates of $0.0004\;s^{-1}$ and of $0.08\;s^{-1}$. The ultimate strength was determined for each specimen. Specimens tested at $0.08\;s^{-1}$ had a mean value of strength 63% higher than the specimens tested at $0.0004\;s^{-1}$. Ultrasound velocity and broadband attenuation were significantly associated with compressive strength at both strain rates. Mechanical strength was also correlated strongly with a linear combination of ultrasound velocity and broadband attenuation for both the low and high loading rates. The use of ultrasound parameters may provide good clinical means for assessing the resistance of trabecular bone to both low and high energy trauma.

• Nutrition Research and Practice
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• v.14 no.6
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• pp.606-620
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• 2020

BACKGROUND/OBJECTIVES: Although some juices affect subjective sleep quality, there is a lack of information on the effect of a specific juice on objective sleep quality and heart rate variability (HRV) during sleep; thus the present study investigated whether a blended juice made from natural extracts influenced sleep quality and HRV during sleep in adults with disturbed sleep. SUBJECTS/METHODS: A randomized, crossover study was conducted on twenty-five adults (15/10, female/male) complaining of difficulty initiating or maintaining nighttime sleep (Pittsburgh sleep quality index [PSQI] ≥ 5). During feeding sessions (FS), subjects received sleep-inducing juice made of natural ingredients (250 mL/trial) twice a day for 8 weeks or non-FS (N-FS) for 8 weeks while maintaining normal activities. Sleep quality and parameters were recorded via wearable actigraph for 7 consecutive days, and PSQI scores were assessed before and after the intervention. HRV was also monitored at rest and during sleep. RESULTS: After receiving the sleep-inducing juice intervention (FS), PSQI scores were significantly decreased (P < 0.001) and correlated with a significant decline in fatigue severity scale and visual analogue scale levels (P < 0.05; both). HRV indices of vagal activity were significantly improved during FS (P < 0.05), and no significant differences in N-FS were observed. Sleep efficiency and total sleep time increased significantly (P < 0.05) and sleep latency, total counts, sleep fragmentation index, and movement index, decreased significantly (P < 0.05, all 4) during FS, with no significant differences-observed during N-FS. CONCLUSIONS: This study results demonstrated that an 8-week course of sleep-inducing juice has led to improve sleep quality, suggesting an enhanced cardiac vagal tone during sleep. Thus, it could be a well-tolerated option for adults with disturbed sleep.

• Journal of Korean Academy of Nursing
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• v.30 no.5
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• pp.1368-1378
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• 2000

This study was conducted to explore the nurse's perception of technological development and professional self-concept. The research subjects were 560 clinical nurses in Korea, who worked the general hospitals in Seoul, Kyeonggi, and the Kangwon province. Data sampling was done for the month, of December. 1997. The research tool consisted of 82 items questionnaires which were demographic data, TIQ, PSCNI. The research findings were as follows: 1. Nurses perceived the technological development as slightly positive (Mean =48.8). Also, nurses saw that the fastest developing technological nursing unit was the cardiac care unit, while the lowest technological developing nursing unit was the psychiatric unit. 2. The view of technological development was found to be significantly different according to religion (P=.0109), marital status (P=.0431), and the practical setting (P=.0048). Professional self concept was significantly different according to age (P=.0001), religion (P=.0001), education (P=.0007), marital status (P=.0000), career (P=.0001), and position (P=.0000). 3. The relationship between a nurse's perception of technological development and professional self-concept was highly correlated(r=.26, P=.0001). In the results of the multiple regression, the factors influencing professional self-concept were career, the nurse's perception of technological development, the level of technological development in nursing unit, and education. All these parameters showed the explaining power of 15.4% of the professional self-concept. In conclusion, nurses recognized the technological development was related to the professional self-concept. This study shed light on the meaning of technological development and vision of the nursing profession. Inservice education program should be developed to help the adaptability to technological development and conduct the qualitative research to explore the world of technological development which the nurses are experiencing in nursing.

• Bulletin of the Korean Chemical Society
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• v.27 no.9
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• pp.1297-1304
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• 2006

A systematic study of the structure, energetics and spectral characteristics of substituted aminoketenes $R(NH_2)$C=C=O (R = H, $CH_3$, $NH_2$, OH, $OCH_3$, CH=$CH_2$, C$\equiv$CH, CN, CHO, NO, $NO_2$) which are highly reactive and transient intermediates in synthesis has been conducted by ab initio calculations at the MP2/6- 31G*//MP2/6-31G* level. Twenty four stable isomers of the eleven substituted aminoketenes having dihedral angles $\phi NH_2\sim120{^{\circ}}$ and $60^{\circ}$ have been identified and their optimized geometries and energies obtained. Electrostatic and steric effects on the molecular geometries have been analyzed. While the $\pi$-acceptor groups lead to planar conformations, the electron-donor groups give rise to non-planar conformations. Isodesmic substituent stabilization energies relative to alkenes have been calculated and correlation with group electronegativities established. Role of induction effect by the substituent groups and resonance effects in charge distribution in the molecules has been analyzed. An analysis of the asymmetric stretching frequencies and intensities of the C=C=O group shows that affect of non-$\pi$ acceptor substituents on the frequency is determined by the field effect (F) and resonance effect (R) parameters, the calculated intensities I (km/mol.) are correlated to group electronegativities $x$ of the substituents by the relationship I = 640.2–100.1 $x$ (r = 0.92). The $\pi$-acceptor substituents increase the intensity which may be explained in terms of their delocalizing effect on the negative charge at the $C_{\beta}$ atom.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.5 s.39
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• pp.1-14
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• 2004

The seismic behavior of a 1/3-scale model of a two-story unreinforced masonry (URM) structure typically used in constructing low-rise residential buildings in Korea is studied through a shaking table test. The purposes of this study are to investigate seismic behavior and damage patterns of the URM structure that was not engineered against seismic loading and to provide its experimental test results. The test structure was symmetric about the transverse axis but asymmetric to some degrees about longitudinal axis and had a relatively strong diaphragm of concrete slab. The test structure was subjected to a series of differentlevels of earthquake shakings that were applied along the longitudinal direction. The measured dynamic response of the test structure was analyzed in terms of various global parameters (i.e., floor accelerations, base shear, floor displacements and storydrift, and torsional displacements) and correlated with the input table motion. Moreover, different levels of seismic performance were suggested for performance-based design approach. The results of the shaking table test revealed that the shear failure was dominant on a weak side of the 1stfloor while the upper part of the test model remained as a rigid body. Also, it was found that substantial strength and deformation capacity existed after cracking.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.7291-7294
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• 2015

Purpsoe: To investigate the diagnostic value of quantitative analysis of a tissue diffusion and virtual touch tissue imaging quantification (VTIQ) technique with acoustic radiation force impulse (ARFI) elastography for assessing enlarged cervical lymph nodes. Materials and Methods: Fifty-six enlarged cervical lymph nodes confirmed by pathologic diagnoses were covered in the study. According to the results of pathologic diagnosis, patients were classified into benign and malignant groups. All the patients were examined by both conventional ultrasonography and elastography. AREA% and shear wave velocity (SWV) in ROI of different groups were calculated and compared using ROC curves. Cut-off points of AREA% and SWV were determined with receiver operating characteristic curves. Results: Final histopathological results revealed 21 cases of benign and 35 cases of malignant lymph nodes. The mean values of AREA% and SWV in benign and malignant groups were $45.0{\pm}17.9%$ and $2.32{\pm}0.57m/s$, and $61.3{\pm}21.29%$ and $4.36{\pm}1.25$)m/s, respectively. For the parameters of elastography, "AREA%" and SWV demonstrated significant differences between groups (p=0.002). AREA% was positively correlated with SWV with a correlation coefficient of 0.809 (P<0.001). Conclusions: Stiffness of different lymph node diseases in patients may differ. Elastography can evaluate changes sensitively and provide valuable information to doctors. The study proved that the VTIQ elastography technique can play an important role in differential diagnosis of lymph nodes.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.195-198
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• 2012

To date, there was no controlled-study regarding awareness and knowledge of colorectal cancer in the Turkish population. We therefore designed a questionnaire consisting of items related to socio-demographic parameters, medical and family history and questions of awareness and knowledge about colorectal cancer for use in a descriptive cross-sectional study. An interviewer-administered technique was applied and 450 subjects were interviewed in the outpatient clinics at Near East University Hospital. Among all subjects, 337 were found to be eligible for the study group. Exclusion criteria were age below 18 years, any cancer history, family history of colorectal cancer, current colorectal problems, history of any diagnostic or therapeutic interventions for colorectal diseases. All participants stated that they heard about colorectal cancer. When asked about the lifetime risk of colorectal carcinoma, only 25.4% of women and 37.9% of men estimated correctly. Univariate analysis revealed that the total awareness score was significantly correlated with age, marital status, parenthood and fecal occult blood testing history. On multivariate analysis of independent predictors for awareness of colorectal cancer were found to be history of fecal occult blood testing, age and marital status were found to be the most important determinants. As a conclusion, opportunistic screening with fecal occult blood test by physicians from non-gastrointestinal specialties not only helps to reduce the mortality but also increases the awareness of colorectal cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.2
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• pp.715-718
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• 2012

The current research concerns the clinicopathological significance of MHC class I chain-related protein A (MICA) expression in oral squamous cell carcinomas (OSCCs). The expression and location of MICA protein in 14 normal oral mucous and 45 cancerous and para-cancerous tissues were assessed by immunohistochemistry and levels of MICA mRNA expression in 29 cancerous and para-cancerous tissues were determined by the real-time polymerase chain reaction. Data were analyzed with the SPSS16.0 software package. MICA was found to be located in the cytoplasm and plasma membrane. Expression was higher in para-cancerous than in cancerous tissues (P < 0.05). However, no statistical difference was found between the following: 1) para-cancerous tissue with normal mucosa; 2) normal mucosa with cancerous tissue;and 3) among different clinicopathological parameters in OSCC (P > 0.05). The level of MICA mRNA was higher in OSCCs than in para-cancerous tissues, and was correlated with the regional lymph node status and disease stage (P < 0.05). The levels of MICA protein and mRNA expression differ among normal oral mucosa, para-cancerous tissue, and cancerous tissue. MICA may contribute to the tumorigenesis and progression of OSCC.

• Geomechanics and Engineering
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• v.15 no.5
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• pp.1091-1100
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• 2018

In this study, the relationships between hydraulic conductivity of GCLs and physico-chemical properties of bentonites were assessed. In addition to four factory manufactured GCLs, six artificially prepared GCLs (AP-GCLs) were tested. AP-GCLs were prepared in the laboratory without bonding or stitching. A total of 20 hydraulic conductivity tests were conducted using flexible wall permeameters ten of which were permeated with distilled deionized water (DIW) and the rest were permeated with tap water (TW). The hydraulic conductivity of GCLs and AP-GCLs were between $5.2{\times}10^{-10}cm/s$ and $3.0{\times}10^{-9}cm/s$. The hydraulic conductivities of all GCLs to DIW were very similar to that of GCLs to TW. Then, simple regression analyses were conducted between hydraulic conductivity and physicochemical properties of bentonite. The best correlation coefficient was achieved when hydraulic conductivity was related with clay content (R=0.85). Liquid limit and plasticity index were other independent variables that have good correlation coefficients with hydraulic conductivity (R~0.80). The correlation coefficient with swell index is less than other parameters, but still fairly good (R~0.70). In contrast, hydraulic conductivity had poor correlation coefficients with specific surface area (SSA), smectite content and cation exchange capacity (CEC) (i.e., R < 0.5). Furthermore, some post-test properties of bentonite such as final height and final water content were correlated with the hydraulic conductivity as well. The hydraulic conductivity of GCLs had fairly good correlation coefficients with either final height or final water content. However, those of AP-GCLs had poor correlations with these variables on account of fiber free characteristics.

• Korean Journal of Materials Research
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• v.20 no.6
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• pp.319-325
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• 2010

3-D IC integration enables the smallest form factor and highest performance due to the shortest and most plentiful interconnects between chips. Direct metal bonding has several advantages over the solder-based bonding, including lower electrical resistivity, better electromigration resistance and more reduced interconnect RC delay, while high process temperature is one of the major bottlenecks of metal direct bonding because it can negatively influence device reliability and manufacturing yield. We performed quantitative analyses of the interfacial properties of Al-Al bonds with varying process parameters, bonding temperature, bonding time, and bonding environment. A 4-point bending method was used to measure the interfacial adhesion energy. The quantitative interfacial adhesion energy measured by a 4-point bending test shows 1.33, 2.25, and $6.44\;J/m^2$ for 400, 450, and $500^{\circ}C$, respectively, in a $N_2$ atmosphere. Increasing the bonding time from 1 to 4 hrs enhanced the interfacial fracture toughness while the effects of forming gas were negligible, which were correlated to the bonding interface analysis results. XPS depth analysis results on the delaminated interfaces showed that the relative area fraction of aluminum oxide to the pure aluminum phase near the bonding surfaces match well the variations of interfacial adhesion energies with bonding process conditions.