• Korean Journal of Poultry Science
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• v.40 no.2
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• pp.121-127
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• 2013

This work was carried to evaluate production efficiency factor, carcass yield and meat quality with weeks of Large-type Korean native ducks. Korean native ducks (n = 90) from National Institute of Animal Science (RDA, Korea) were used in this work. Ninety ducks were divided into 6 groups (15 birds/group) and were fed with meat-type duck diets for 8 wk old. When ducks grew at specific wk (6, 7 and 8 weeks), 2 ducks per group were slaughtered at 6, 7 and 8 wk old. Production efficiency factor, carcass yield, partial meat and meat quality were researched in this work. There was no significant difference on livability with weeks, but body weight at 7 and 8 wk old was higher than that at 6 wk old (P<0.05). Feed conversion ratio at 6, 7 and 8 wk old were 2.25, 2.69 and 3.21, respectively, so there was significant difference with weeks (P<0.05). Production efficiency factor at 6, 7 and 8 wk old were 256.6, 199.8 and 153.0, respectively, so there was significant difference with weeks (P<0.05). Carcass yield at 8 wk old was higher than that at 6 and 7 wk old as 73.5% (P<0.05). Lightness at 6, 7 and 8 wk were 41.8, 39.0 and 38.1, respectively, and that at 6 wk old was the higher than other weeks (P<0.05). There was no significant difference on redness at 6, 7, and 8 wk old (P>0.05) and yellowness at 8 wk old was higher compared to other weeks (P<0.05). Cooking loss was the highest at 6 wk old as 31.6%, but water holding capacity was the highest at 8 wk old (P<0.05). There was no significant difference on shear force among weeks. pH at 6 wk old was the lower than that of other weeks as 5.84. Moisture content significantly decreased with weeks (P<0.05) and fat content at 8 wk was the highest as 1.88% (P<0.05). Protein content significantly increased with weeks until 20.9% at the age of 8 wk (P<0.05). Ash content at 7 and 8 wk old was the higher than that at 6 wk old (P<0.05). There was no significant difference on juiciness, tenderness, and flavor with weeks. Finally, these results may provide that shipping time at 7 wk old preferred to that at 6 and 7 wk old, but further research was needed because of deficiency of data.

• Investigative Magnetic Resonance Imaging
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• v.8 no.2
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• pp.79-85
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• 2004

Purpose : To evaluate the usefulness and reproducibility of $^1H$ MRS in different 1.5 T MR machines with different coils to compare the SNR, scan time and the spectral patterns in different brain regions in normal volunteers. Materials and Methods : Localized $^1H$ MR spectroscopy ($^1H$ MRS) was performed in a total of 10 normal volunteers (age; 20-45 years) with spectral parameters adjusted by the autoprescan routine (PROBE package). In all volunteers, MRS was performed in a three times using conventional MRS (Signa Horizon) with 1 channel coil and upgraded MRS (Echospeed plus with EXCITE) with both 1 channel and 8 channel coil. Using these three different machines and coils, SNRs of the spectra in both phantom and volunteers and (pre)scan time of MRS were compared. Two regions of the human brain (basal ganglia and deep white matter) were examined and relative metabolite ratios (NAA/Cr, Cho/Cr, and mI/Cr ratios) were measured in all volunteers. For all spectra, a STEAM localization sequence with three-pulse CHESS $H_2O$ suppression was used, with the following acquisition parameters: TR=3.0/2.0 sec, TE=30 msec, TM=13.7 msec, SW=2500 Hz, SI=2048 pts, AVG : 64/128, and NEX=2/8 (Signa/Echospeed). Results : The SNR was about over $30\%$ higher in Echospeed machine and time for prescan and scan was almost same in different machines and coils. Reliable spectra were obtained on both MRS systems and there were no significant differences in spectral patterns and relative metabolite ratios in two brain regions (p>0.05). Conclusion : Both conventional and new MRI systems are highly reliable and reproducible for $^1H$ MR spectroscopic examinations in human brains and there are no significant differences in applications for $^1H$ MRS between two different MRI systems.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.1
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• pp.42-48
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• 2007

Purpose: The purpose of this study is to image metastaic lung melanoma model with optimal pre-conditions for animal handling by using $[^{18}F]FDG$ small animal PET and clinical CT. Materials and Methods: The pre-conditions for lung region tumor imaging were 16-22 h fasting and warming temperature at $30^{\circ}C$. Small animal PET image was obtained at 60 min postinjection of 7.4 MBq $[^{18}F]FDG$ and compared pattern of $[^{18}F]FDG$ uptake and glucose standard uptake value (SUVG) of lung region between Ketamine/Xylazine (Ke/Xy) and Isoflurane (Iso) anesthetized group in normal mice. Metastasis tumor mouse model to lung was established by intravenous injection of B16-F10 cells in C57BL/6 mice. In lung metastasis tumor model, $[^{18}F]FDG$ image was obtained and fused with anatomical clinical CT image. Results: Average blood glucose concentration in normal mice were $128.0{\pm}23.87$ and $86.0{\pm}21.65\;mg/dL$ in Ke/Xy group and Iso group, respectively. Ke/Xy group showed 1.5 fold higher blood glucose concentration than Iso group. Lung to Background ratio (L/B) in SUVG image was $8.6{\pm}0.48$ and $12.1{\pm}0.63$ in Ke/Xy group and Iso group, respectively. In tumor detection in lung region, $[^{18}F]FDG$ image of Iso group was better than that of Ke/Xy group, because of high L/B ratio. Metastatic tumor location in $[^{18}F]FDG$ small animal PET image was confirmed by fusion image using clinical CT. Conclusion: Tumor imaging in small animal lung region with $[^{18}F]FDG$ small animal PET should be considered pre-conditions which fasting, warming and an anesthesia during $[^{18}F]FDG$ uptake. Fused imaging with small animal PET and CT image could be useful for the detection of metastatic tumor in lung region.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.1
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• pp.9-15
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• 2007

Purpose: Repetitive transcranial magnetic stimulation (rTMS) has recently been clinically applied in the treatment of drug resistant depressed patients. There are mixed findings about the efficacy of rTMS on depression. Furthermore, the influence of rTMS on the physiology of the brain is not clear. We prospectively evaluated changes of regional cerebral blood flow (rCBF) between pre- and post-rTMS treatment in patients with drug resistant depression. Materials and Methods: Twelve patients with drug-resistant depression (7 male, 5 female; age range: $19{\sim}52$ years; mean age: $29.3{\pm}9.3$ years) were given rTMS on right prefrontal lobe with low frequency (1 Hz) and on left prefrontal lobe with high frequency (20 Hz), with 20-minute-duration each day for 3 weeks. Tc-99m ECD brain perfusion SPECT was obtained before and after rTMS treatment. The changes of cerebral perfusion were analyzed using statistical parametric mapping (SPM; t=3.14, uncorrected p<0.01, voxel=100). Results: Following areas showed significant increase in rCBF after 3 weeks rTMS treatment: the cingulate gyrus, fusiform gyrus of right temporal lobe, precuneus, and left lateral globus pallidus. Significant decrement was noted in: the precental and middle frontal gyrus of right frontal lobe, and fusiform gyrus of left occipital lobe. Conclusion: Low-frequency rTMS on the right prefrontal cortex and high-frequency rTMS on the left prefrontal cortex for 3 weeks as an add-on regimen have increased and decreased rCBF in the specific brain regions in drug-resistant depressed patients. Further analyses correlating clinical characteristics and treatment paradigm with functional imaging data may be helpful in clarifying the pathophysiology of drug-resistant depressed patients.

• Journal of Society of Preventive Korean Medicine
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• v.5 no.2
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• pp.40-68
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• 2001

In this study, grade of subjective symptom appealed by laborer of Jeollabuk-do was evaluated using questionary regarding factor made effect on musculoskeletal disease and in addition, studied relationship with health promotion life style of them. Based on the result, relationship of general characteristics of musculoskeletal subjective symptom and life-style of the subjects was concluded as below. 1. General characteristics of study subjects were as following. Ratio of male was higher as 57.7% of male and 42.2% female and age distribution was 5.1% of 20s, 34.99% of 30s, 36.3% of 40s and 23.7% of 50s and therefore, $30{\sim}40$ aged groups showed highest ratio. Most subjects (74.9%) was married status and in case of education level, high-school graduate and dropout (23.3%) and over-college graduate (46.8%) showed highest distribution. $1{\sim}2$ Mil. KRW (29.5%) and $2{\sim}2.99$ Mil. KRW (21.2%) is the main income distribution and however there was high ratio of non-reply (29.0%). In case of employment period, $10{\sim}14$ years (15.3%) and over 15 years (29.6%) showed highest ratio and there were many non-reply (39.4%) and in addition, 67.6% replied as own house and 14.3% as lease on deposit base in question of residence type. 2. Subjects showed high ratio of subjective symptom appeal of 62.79% and many cases (50.23%) appealed 1 or 2 symptoms. Symptom by body region was 29.8% (waist), 27% (shoulder), 21.2% (knee), 15.5% (neck), 9.5% (ankle), 8.1% (wrist) and 5.0% (elbow) in order. In case of relationship with general characteristics, female comparing with male, non-residence of own house, subjects with lower education level and employment period of $10{\sim}14$ years showed higher appeal rate and kind of symptoms than others. Therefore, it was concluded that rate of musculoskeletal symptom appeal have close relationship with gender, level of living, education level, age and employment period. 3. In case of severe pain of upper body except waist and ankle, it was appealed in both or right side and it means that upper body pain is originated from right side and right region pain is transited to both region pain. In addition, there was 39.41% of non-reply to existence of right-left region pain and therefore, it was evaluated that, in may cases, there was no awareness of their own symptom condition even on subjective symptom. 4. Degree of pain was, as pain over middle level, evaluated as 2.79 on full mark of 4.0 and in order of waist (2.97), ankle (2.83), knee (2.82), wrist (2.82), neck (2.79), shoulder (2.70) and elbow (2.62). In addition, 71.97% appealed $2{\sim}3$ cases for the latest 1 week. Owing to subjective symptom, 54.95% drop into hospital or pharmacy, 10.32% made temporary retirement or absence, 7.99% transferred into more comfortable duty and $39.4{\sim}54%$ experienced one or more managing mentioned above. 5. Fulfillment of health promotion life style of subjects was evaluated on full mark of 4.0 and total score was 2.63. Average mark of each area was personal relationship (3.05), self-realization (2.92), stress management (2.63), health control (2.48), physical exercise (2.19) and nutrition management (2.19) and personal relationship was highest and physical exercise and nutrition management were lowest. As general characteristics influencing health promotion life style, gender, residence style and employment period showed significant difference. Male showed higher mark than female and showed higher mark in order of own house, others, lease on deposit base, monthly rent. Subjects with longer employment period showed higher mark with significant difference. 6. Accounting of factor influencing each area of health promotion life style, self-realization showed significance in marriage status, income, residence style and education level and health control in age, residence style and employment period. Physical exercise showed significant difference in gender, age, residence style and employment period and nutrition in gender, age, residence style and employment period. Stress management showed significant difference in residence style and employment period and however not in personal relationship. 7. Health promotion life style relating with existence and kind of pain showed significant difference in all area except personal relationship area. In absence of pain, there was statistically significant high score in all area even in total health promotion life style and all area. Accounting of kind of pain, cases of $1{\sim}2$ kinds of pain and $5{\sim}6$ kinds of pain showed relatively high score and it was lower than mark of subject stated absence of pain. 8. Subjects appeal symptom were classified by symptom region and difference of total and each areas were evaluated. General area (p=0.002), self-realization (p=0.012), health management (p=0.023), physical exercise (p=0.028), nutrition management (p=0.028) and stress control (p=0.001) showed statistically significant difference and not in personal relationship area. Especially, elbow, shoulder and neck area marked high and group appealed pain of knee, arm and elbow, foot and ankle marked low. Based on those results, subjective symptom should be accounted seriously in diagnosis of occupational musculoskeletal disease of laborer and among subjective symptom, general characteristics of gender, age, condition of living, education level and employment period make effect. Generally subject appeal symptom marked lower than subject without symptom appeal and it means that life management of subject appealing musculoskeletal pain make important role in management and treatment of occupational musculoskeletal disease.

• Journal of Society of Preventive Korean Medicine
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• v.4 no.2
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• pp.72-92
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• 2000

This research has conducted studies on an Oriental medicine-based method of diagnosing of occupational musculoskeletal system diseases. This researcher has searched through existing relevant medical literature. Also, this researcher has worked on a moire topography using moire topography. In this course, this researcher has reached the following conclusion in relation to the possibility of using a moire topography as a diagnosing device of musculoskeletal system diseases under Oriental medicine . 1 The Western medicine outlines its criteria of screening occupational musculoskeletal system diseases as follows A. The occupational musculoskeletal diseases must clearly include one or more of the subjective symptoms characterized by pain, hypoesthesia dysaesthesia, anaesthesia. etc . B, There should be clinically admitted objective observations and diagnosis outlining that the disease concerned shows symptoms such as tenderness, induration. and edema that can appear with occupational musculoskeletal system diseases. dyscinesia should be admitted with the disease concerned, or there should be observations and diagnosis outlining that abnormality exists in electric muscular or nervous diagnosis and examination . C. It should be admitted that prior to the occurrence of symptoms or observations and diagnosis on musculoskeletal system-related diseases, a patient has been engaged in works with conditions requiring improper work posture or work movement. That is, this is an approach whereby they see abnormality in the musculoskeletal system come from material and structural defect, and adjust and control abnormality in the musculoskeletal system and secreta . 2. The Oriental medicines sees that a patient develops the pain of occupational musculoskeletal diseases as he cannot properly activate the flow of his life force and blood thus not only causing formation of lumps in the body and blocking the flow of life force and blood in some parts of the body. Hence, The Oriental medicine focuses on resolving the cause of weakening the flow of life force and blood, instead of taking material approach of correcting structural abnormality Furthermore , Oriental medicine sees that when muscle tension builds up, this presses blood vessels and nerves passing by, triggering circulation dyscrasia and neurological reaction and thus leading to lesion. Thus, instead of taking skeletal or neurophysiological approach. it seeks to fundamentally resolve the cause of the flow of the life force and blood in muscles not being activated. As a result Oriental medicine attributes the main cause of musculoskeletal system diseases to muscle tension and its build-up that stem from an individual's long formed chronicle habit and work environment. This approach considers not only the social structure aspect including companies owners and work environment that the existing methods have looked at, but also individual workers' responsibility and their environmental factors. Hence, this is a step forward method. 3 The diagnosis of musculoskeletal diseases under Oriental medicine is characterized by the fact that an Oriental medicine doctor uses not only photos taken by himself, but also various detection devices to gather information and pass comprehensive judgment on it. Thus, it is the core of diagnosis under Oriental medicine to develop diagnosing devices matching the characteristics of information to be induced and to interpret information so induced from the views of Oriental medicine. Diagnosis using diagnosing devices values the whole state of a patient and formal abnormality alike, and the whole balance and muscular state of a patient serves as the basis of diagnosis. Hence, this method, instead of depending on the information gathered from devices under Western medicine, requires devices that provide information on the whole state of a patient in addition to the local abnormality information that X-ray. CT, etc., can offer. This method sees muscle as the central part of the abnormality in the musculoskeletal system and thus requires diagnosing devices enabling the muscular state. 4. The diagnosing device using moire topography under Oriental medicine has advantages below and can be used for diagnosing musculoskeletal system diseases with industrial workers . First, the device can Provide information on the body in an unbalanced state. and thus identify the imbalance and difference of height in the left and right stature that a patient can not notice at normal times. Second, the device shows the twisting of muscles or induration regions in a contour map. This is not possible with existing shooting machines such as X-ray, CT, etc., thus differentiating itself from existing machines. Third, this device makes it possible for Oriental medicine to take its unique approach to the abnormality in the musculoskeletal system. Oriental medicine sees the state and imbalance state in muscles as major factors in determining the lesion of musculoskeletal system, and the device makes it possible to shoot the state of muscles in detail. In this respect, the device is significant. Fourth, the device has an advantage as non-aggression diagnosing device.

• Journal of the Korean Society of Radiology
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• v.7 no.2
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• pp.113-120
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• 2013

Nowadays, the medical system towards patients changes into the medical services. As the human rights are improved and the capitalism is enlarged, the rights and needs of patients are gradually increasing. Also, based on this change, several systems in hospitals are revised according to the convenience and needs of patients. Thus, the cases of mobile portable among examinations are getting augmented. Because the number of mobile portable examinations in patient's room, intensive care unit, operating room and recovery room increases, neighboring patients are unnecessarily exposed to radiation so that the examination is legally regulated. Hospitals have to specify that "In case that the examination is taken out of the operating room, emergency room or intensive care units, the portable medical X-ray protective blocks should be set" in accordance with the standards of radiation protective facility in diagnostic radiological system. Some keep this regulation well, but mostly they do not keep. In this study, we shielded around the Collimator where the radiation is detected and then checked the change of dose regarding that of angles in portable tube and collimator before and after shielding. Moreover, we tried to figure out the effects of shielding on dose according to the distance change between patients' beds. As a result, the neighboring areas around the collimator are affected by the shielding. After shielding, the radiation is blocked 20% more than doing nothing. When doing the portable examination, the exposure doses are increased $0^{\circ}C$, $90^{\circ}C$ and $45^{\circ}C$ in order. At the time when the angle is set, the change of doses around the collimator decline after shielding. In addition, the exposure doses related to the distance of beds are less at 1m than 0.5m. In consideration of the shielding effects, putting the beds as far as possible is the best way to block the radiation, which is close to 100%. Next thing is shielding the collimator and its effect is about 20%, and it is more or less 10% by controlling the angles. When taking the portable examination, it is better to keep the patients and guardians far enough away to reduce the exposure doses. However, in case that the bed is fixed and the patient cannot move, it is suggested to shield around the collimator. Furthermore, $90^{\circ}C$ of collimator and tube is recommended. If it is not possible, the examination should be taken at $0^{\circ}C$ and $45^{\circ}C$ is better to be disallowed. The radiation-related workers should be aware of above results, and apply them to themselves in practice. Also, it is recommended to carry out researches and try hard to figure out the ways of reducing the exposure doses and shielding the radiation effectively.

• Radiation Oncology Journal
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• v.12 no.2
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• pp.151-158
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• 1994

Since Jan. 1992, authors have conducted a pilot study to treat malignant glioma with multiple daily fractionated(MDF) radiation therapy and this paper presents the outcome compared MDF to conventional factionated(CF) radiation therapy Between Sep. 1989 and Jan. 1993, forty three patients with high grade glioma of brain except brain stem glioma were treated: nineteen patients were treated with CF radiation therapy and 24 patients were treated with MDF radiation therapy. In CF radiation therapy, total dose was 6300cGy/35fx in 7 weeks, which 5040cGy was delivered to the initial target volume and 1260cGy to reduced target volume. And in MDF radiation therapy, total dose was 6400cGy/40fx in 4 weeks, which 3200cGy was delivered to the initial target volume as 160cGy 2 times daily 6hr apart. All patients had histologically confirmed anaplastic astrocytoma(AA) of glioblastoma multiforme (GBM) with stereotactic biopsy or craniotomy for subtotal or gross tumor resection. The range of follow-up was 7 months to 4 years with a median follow-up of 9 months. The Median survival from surgery was 9 months for all patients. The median survival was 9 months and 10 months for MDF group and CF group and 10 months and 9.5 months for glioblastoma multiforme and anaplastic astrocytoma, respectively. In 36 patients with follow-up CT scan or MRI scan, disease status was evaluated according to treatment groups, Four patients(GBM:3, AA:1) of 21 patients in MDF group, were alive with no evidence of disease, while none of patient was alive with no evidence of disease in CF group. The progression of disease had occurred in 20 patients, 11 patients and 9 patients in MDF group and CF group, respectively All of these patients showed in-field progression of disease, Four of 11 patients($27\%$) in MDF group showed the new leasion outside of the treatment field, while 5 of 9 patients($56\%$) in CF group. In our study the prognosis was not influenced by age, KPS, grade, extent of surgery and different fractional scheduled radiation therapy. Authors concluded that MDF regimen was well tolerated and shortened the treatment period from 7 weeks to 4 weeks without compromising results. We believe that further follow-up is needed to assess the role of MDF.

• Asia pacific journal of information systems
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• v.20 no.4
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• pp.53-79
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• 2010

The study was originated from recognition that project participants' satisfaction should be Improved to raise project performance and to make progress of a successful project since the above dissatisfaction was operated as a danger factor of the project. The study selected one large-scale sample project and attempted measuring characteristics of the project, participants' satisfaction and project performance with the whole project participants. The study analyzed correlations between individual level (team members) and group level (development team), and examined what effect a sub project manager under complicated hierarchical organization of the large-scale project, namely PL (project leader)'s leadership style had on each individual project participant's satisfaction and what effect project uncertainty in organization/technology environment had on project participants' satisfaction and project performance. The study verified that development team (group) had an effect on team member (individual)-level project participants' satisfaction by disclosing that there was a significant dispersion among groups within project participants' satisfaction by each individual. It is analyzed that it is necessary to make improvement through approach by each pertinent team to raise individual-level project participants' satisfaction. The study also verified PL's ideal leadership under strict methodology and hierarchical control of the large-scale project. Based on the verification of the hypotheses, the results of the analysis were produced as follows. First, the development team affects the satisfaction level that an individual has when he/she participates in a project. This suggests that the satisfaction with project participation should be improved at the team level. In addition, the project management style and leadership orientation of the manager of a sub project who is mostly affected by the team proved to have a direct influence on the satisfaction with project participation and project performances. Second, both the performance-oriented leadership and the relationship-oriented leadership of the PL of the development team were verified to have a significant effect on the satisfaction of the team members associated with project participation. In other words, when the team members recognize that the PL of the development team shows both the performance-oriented leadership and the relationship-oriented leadership, their satisfaction with project participation increases accordingly. Third, it was verified that the uncertainty of the organizational environment significantly affects the satisfaction level when the PL of the development team exerts a relationship-oriented and performance-oriented leadership. The higher the uncertainty of the organizational environment is, the more the satisfaction with project participation decreases whereas the relationship-oriented leadership has a more positive effect on the satisfaction than the performance-oriented leadership style. Fourth, when the PL of the development team exerts the relationship-related and performance-related leadership, the uncertainty of the technological environment has a significant influence on the satisfaction level. The higher the uncertainty of the technological environment is, the more the satisfaction with project participation decreases whereas the performance-oriented leadership has a more positive effect on the satisfaction than the relationship-oriented leadership style. The result of the research on the uncertainty of the project environment suggests that when the development team leader exerts a relationship-oriented and performance-oriented leadership style, the uncertainty of the organizational environment has a significant effect on the satisfaction with project participation; the higher the uncertainty of the organizational environment, the more the satisfaction level decreases, and the relationship-oriented leadership style affects the satisfaction level more positively than the performance-oriented leadership style. In addition, when the development team leader displays a relationship-oriented and performance-oriented leadership style, the uncertainty of the technological environment has a significant effect on the satisfaction with project participation; the higher the uncertainty of the technological environment. the more the satisfaction level decreases. The performance-oriented leadership style as well affects the satisfaction level more positively than the relationship-oriented leadership style. Based on the above results, the research provides the following implications when handling multiple concurrent projects. First, the satisfaction with the participation in the multiple concurrent projects needs to be enhanced at the team (group) level. Second. the manager of the project team, particularly the middle managers should have both a performance-oriented and relationship (task and human)-oriented attitude and exert a consolidated leadership in order to improve the satisfaction of team members with project participation and their performances. Third, as the uncertainty factor of the technological and organizational environment among the characteristics factors of the project has room for methodological improvement depending on one's effort even though there are some complications, we need to continuously prevent and control the risks resulting from the uncertainties of the technological and organizational environment of the project in order to enhance the satisfaction of project participation and project performances. Fourth, the performance (task)-oriented leadership is required when there is uncertainty in a technological environment while the relationship (human)-oriented leadership is required when there is uncertainty in an organizational environment. This research has the following limitations. First, this research intended to select one large-sized sample project and measure the project characteristics, the satisfaction of all the participants associated with project participation, and their performances. Therefore, it is inappropriate to generalize and apply the result of this result onto other numerous projects. Second, as this case study entailed a survey to measure the characteristics factors and performance of the project, since the result value was based on the perception of project team members, the data may have insufficient objectivity. Third, though this research targeted on all the project participants, some development teams did not provide sufficient data and questionnaires were collected from some specific development teams among the 23 development teams, causing a significant deviation in the response rate among the development teams. Therefore, we need to continuously conduct the follow-up researches making comparisons among the multiple projects, and centering on the characteristics factors of the project and its satisfaction level.

• Analytical Science and Technology
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• v.5 no.1
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• pp.41-49
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• 1992

An attempt was made to prepare two series of tetrakis eight-coordinate tungsten(IV) and cerium(IV) complexes containing the 5,7-dichloro-8-quinolinol(N:${\pi}$-acceptor atom, O:${\pi}$-donor atom) ligand. Tetrakis eight-coordinate tungsten(IV) complex of 2-mercaptopyrimidine(N:${\pi}$-acceptor atom, S:${\pi}$-donor atom) ligand have also been prepared. And the new series of mixed-ligand eight-coordinate tungsten(IV) complexes containing bidentate ligands 5,7-dichloro-8-quinolinol and 2-mercaptopyrimidine have been prepared, isolated by TLC and characterized. $W(dcq)_4$, $W(dcq)_3(mpd)_1$, $W(dcq)_2(mpd)_2$, $W(dcq)_1W(dcq)_3$ and $W(mpd)_4$ complexes of MLCT absorption band appeared to 710nm, 680nm, 625nm, 581nm, and 571nm(${\varepsilon}\;max={\sim}>{\times}10^4$) on low-energy respectively. The specific absorption wave length of $Ce(dcq)_4$ is appeared 520nm(${\varepsilon}\;max={\sim}>{\times}10^4$). The Chemical shift values by proton of coordinated position appeared to $W(dcq)_4$ [$H_2:8.9ppm$]; $W(dcq)_3(mpd)_1$ [$H_2:9.3$,$H_6:9.2ppm$]; $W(dcq)_2(mpd)_2$ [$H_2:9.7$,$H_6:8.95ppm$]; $W(dcq)_1(mpd)_3$ [$H_2:9.8$,$H_6:9.4ppm$]; $W(mpd)_4$ [$H_6:8.8ppm$]; $Ce(dcq)_4$ [$H_2:9.3ppm$] with $^1H$-NMR. The inertness of mixed-ligand eight coordinate tungsten(IV) complexes have been investigated by UV-Vis. spectroscopic method in dimethylsulfoxide at $90^{\circ}C$. The inertness of $W(dcq)_n(mpd)_{4-n}$ complexes showed the following order, $W(dcq)_3(mpd)_1;k_{obs.}=3.8{\times}10^{-6}$ > $W(mpd)_4;k_{obs.}=6.0{\times}10^{-6}$ > $W(dcq)_4;k_{obs.}=6.4{\times}10^{-6}$ > $W(dcq)_2(mpd)_2;k_{obs.}=7.0{\times}10^{-6}$ > $W(dcq)_1(mpd)_3;k_{obs.}=1.7{\times}10^{-5}$, which showed the inertness until 16days, 10days, 9days, 8days, and 4days. The $W(mpd)_4$ is very inert as $k_{obs.}=3.6{\times}10^{-6}$(16days) in xylene at $90^{\circ}C$ and $k_{obs.}=6.0{\times}10^{-6}$(10days) in DMSO at $90^{\circ}C$.