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Maternal separation during early life causes psychiatric and neurologi-cal disorders such as anxiety and depression. Depression or anxiety is closely associated with memory impairment. The purpose of this study was to investigate the effect of treadmill exercise on activity, short-term memory, vascular dysfunction using maternal separation-induced de-pression model. Maternal separation started on 15-day-old rats. The rats in the maternal separation and fluoxetine injection group received intraperitoneal injection of 5 mg/kg of fluoxetine one time daily for 15 days from 21 to 35 days. The rats performed treadmill exercise once a day during 15 days from 21 to 35 days. There was low activity and short-term memory was decreased in the maternal separation rats. Treadmill exercise and fluoxetine injection increased activity and ameliorated memory impairment. The number of rat endothelial cells antigen-1 (RECA-1) of microvessels was decreased in the maternal separation rats. The number of RECA-1was increased by treadmill exercise and fluoxetine injection. Expression of matrix metalloproteinase-9 (MMP-9) was increased and expressions of zonula occludens-2 (ZO-2) and oc-cludin were decreased in the maternal separation rats. Treadmill exer-cise and fluoxetine injection suppressed MMP-9 expression and en-hanced ZO-2 and occludin expressions in the maternal separation rats. The present study shows treadmill exercise and antidepressant treat-ment ameliorates depressive symptom and short-term memory impair-ment by protecting from blood-brain barrier damage.

The finite element method using the damage model has been increasingly used to predict the failure of various structures. Thus, various damage models were presented, and recently, a phenomenological model called the local fracture strain model was presented, making it easy and accurate to predict the damage of the structure. This model has the advantage of defining fracture strain as a function of stress triaxiality with only a few notched tensile tests but has a limitation because it does not consider the damage evolution because of the void growth. This study presents an enhanced damage model that improves the accuracy of the failure simulation of defected structures by adding a parameter that considers stiffness degradation according to void growth to the damage model based on the fracture strain. Therefore, loading–unloading tests were conducted and the damage index of fracture was identified using a three-dimensional digital image correlation system. The failure simulation results using the proposed damage model were compared with experimental, such as notched tensile, single edge notched tension (SENT), and full-scale burst tests.

The purpose of this study was to investigate the effect of a stretching program, based on the Janda approach and compared with a static stretching program, on range of motion (ROM), muscle strength and pain. Subjects for this study were 11 middle-aged women with self-reported muscular skeletal symptoms. The subjects were randomly divided into six women as an experimental group (stretching based on Janda approach group, SJAG) and five women as the comparison group (traditional static stretching group, TSSG). Static stretching program in both groups consisted of 14 types of exercise and strength program in SJAG was comprised of five isometric contractions. The stretching program was performed 3 times per week for 6 weeks. The ROM and muscle strength of the neck and shoulder region were measured and a numerical rating scale was used for measuring pain. Significant differences between groups were determined with two-way repeated analysis of variance and paired t-test. As a result of this study, the ROM did not show generally significant changes but was affirmatively improved in both groups. SJAG showed significant improvement in muscle strength and pain reduction compared to the TSSG. Consequently, a stretching program based on the Janda approach would be more effective on self-reported muscular skeletal symptoms caused by posture misalignment than a static stretching program.

The purpose of this study was to investigate the effect of group jump rope exercise on health-related fitness, growth hormone (GH), and insulin growth factor-Ⅰ(IGF-Ⅰ) in male middle school students. Twenty students were randomly selected as study subjects. This study is divided into two groups: the jump rope exercise group (n=10) and the control group (n=10). The exercise group performed a 50-minute group jump rope exercise program 3 times a week for 12 weeks. And the jump rope exercise consisted of long 8-figure marathon, long 4-leap, and long hopping in and jump the roping together. The control group only performed their regular daily activities. Repeated measures ANOVA was used to analyze the difference according to the group and the exercise period. The results showed that the right grip strength and back strength in the jump rope exercise group were further increased when compared to the control group. Jump rope exercise not only significantly decreased body mass index (BMI) and body fat percentage(%BF) but also increased left grip strength, muscle endurance, cardiovascular endurance, and flexibility. In the result of the hormone analysis, jump rope exercise increased GH concentration in the blood but there is no significant between two groups. IGF-Ⅰ in the jump rope exercise group showed significant increase compared to the control group. In conclusion, this study indicates that a 12 weeks of group jump rope exercise may has positive effects on health-related fitness, GH and IGF-Ⅰ in male middle school students.

The purpose of this study was to investigate the effect of a 12-week circuit training program on health-related physical fitness and metabolic syndrome risk factors in obese female college students. Twenty subjects with over 30% of accumulated body fat voluntarily participated and were randomly allocated to the control group (n=10) or circuit training group (n=10). The circuit training program consisted of 10 types of resistance and aerobic exercise and was performed 3 times per week for 12 weeks. Health-related physical fitness and metabolic syndrome risk factors were analyzed to elucidate the effect of the circuit training. Significant differences between groups were determined with two-way repeated analysis of variance and paired t-test. As a result of this study, body weight, % body fat, and body mass index in the circuit training group was significantly decreased compared to the control group. All health-related physical fitness indicators such as back strength, sit-up, sit-and-reach, and 1,600 m running time showed relative effects between groups or over time. Among the metabolic syndrome risk factors, waist measurement, triglyceride, and total cholesterol were significantly decreased but blood glucose, high-density lipo-protein cholesterol and low-density lipoprotein cholesterol did not show any significant difference. Therefore, the present data suggested that circuit training for 12 weeks may be effective in improving physical fitness and preventing metabolic diseases.

Diabetes mellitus is associated with the impairment of sexual function including desire and orgasmic dysfunction. Sexual dysfunction in the diabetes mellitus is due to a selective defect of the nitric oxide synthase (NOS) within paraventricular nucleus (PVN). c-Fos is an immediate ear-ly gene and c-Fos expression represents neuronal activity in response to various stimuli. In the present study, we investigated the effects of treadmill exercise on sexual behaviors and the expressions of NOS and c-Fos in the PVN were evaluated using streptozotocin (STZ)-induced diabetic rats. Diabetes mellitus was induced by intraperitoneal injection of STZ. The rats in the treadmill exercise groups were made to run on a treadmill for 30 min once a day during 4 weeks. Male sexual behaviors were evaluated by recording the number of mounting, intromission, and ejaculation frequency. The present results revealed that treadmill exer-cise ameliorated sexual dysfunction in the STZ-induced diabetic rats. Treadmill exercise restored the contents of NOS and c-Fos in the PVN. The improving effect of treadmill exercise on sexual function can be considered as the neuronal activating effect of exercise through in-creasing expressions of NO and c-Fos.

Social isolation is known to induce emotional and behavioral changes in animals and humans. The effect of treadmill exercise on depression was investigated using social isolated rat pups. The rat pups in the social isolation groups were housed individually. The rat pups in the exercise groups were forced to run on treadmill for 30 min once a day from postnatal day 21 to postnatal day 34. In order to evaluate depression state of rat pups, forced swimming test was performed. Newly generated cells in the hippocampal dentate gyrus were determined by 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry. We examined the expression of 5-hydroxytryptamine (5-HT) and tryptophan hydroxylase (TPH) in the dorsal raphe using immunofluorescence. The expression of brain-derived neurotrophic factor (BDNF) and tyrosine kinase B (TrkB) was detected by Western blot analysis. The present results demonstrated that social isolation increased resting time and decreased mobility time. Expression of 5-HT and TPH in the dorsal raphe and expression of BDNF and TrkB in the hippocampus were decreased by social isolation. The number of BrdU-positive cells in the hippocampal dentate gyrus was suppressed by social isolation. Treadmill exercise decreased resting time and increased mobility in the social isolated rat pups. Expression of 5-HT, TPH, BDNF, and TrkB was increased by treadmill exercise. The present results suggested that treadmill exercise may ameliorates social isolation-induced depression through increasing neuronal generation.

Hydrogen usually penetrates metals through defects such as dislocations, vacancies, and crystalline imperfections and causes embrittlement, leading to cleavage fracture and intergranular fracture. Synthetic natural gas produced by coal gasification, biogas, and landfill gas inevitably contain hydrogen. Therefore, hydrogen embrittlement of pipeline materials should be considered when they are mixed with conventional natural gas and supplied to customers. To analyze hydrogen embrittlement of base metals and girth weld metals of API 5L X70 and X65 gas pipelines, a specimen was treated in 100 % hydrogen environment at 10 MPa to determine the hydrogen concentration in it. Small punch (SP) tests were performed under various gaseous components and pressures. When SP tests were performed at very low speed, hydrogen embrittlement could be observed. Specimens became very susceptible to hydrogen embrittlement with increasing hydrogen partial pressure in the hydrogen/methane gas mixture, and the SP energy also decreased dramatically.

Mobile X-ray device is widely employed because it is useful for diagnosis in patients having mobility difficulties and in medical emergencies. As various devices for X-ray generation have continued to be developed, X-ray devices can now be used more safely and effectively. However, mobile X-ray devices generate relatively low X-ray doses due to the limitation of the power input. Therefore, the use of mobile X-ray devices is limited to thin parts of body. In this study, a new device was designed in order to increase the usefulness of mobile X-ray devices by offsetting the weaknesses of the existing mobile X-ray devices, rendering them useable independently. A supercapacitor and battery were used as the internal power source for the X-ray generation in the manufactured device. The pulse width modulation (PWM) method is applied to control the tube voltage and current required for generating the X-ray, and the pulse frequency modulation (PFM) method is applied to the control to generate the high voltage in order to enhance the precision and efficiency. The manufactured X-ray device was used to evaluate the control signal, frequency, and output characteristics according to changes in tube voltage and current. Based on the results of X-ray generation, it is confirmed that precise control was achieved by X-ray generation increases linearly with increasing tube voltage and tube current. This means that precise control of the manufactured mobile X-ray device is passible. In addition, the study confirmed that stable output was achieved by checking the tube voltage, tube current and exposure rate during the exposure times by high power condition.

The technology development of pipeline transportation of natural gas at artic and northern ice environments should be considered with unique characteristics of permafrost territory as a very interesting and challenging area. This work is to investigate bottleneck techniques and major impact factors through a literature search to figure out the core technology of the transport pipeline. Especially, theoretical approach themes could be determined to develop the technology flow assurance for permafrost regions through documentary survey on the considerations of thermo-fluid. Also, basic results through theoretical approaches could be achieved.

It is known that there is no demand for building the arctic environment in Korea. However, it is important to use the different energy source instead of fuel source due to global warming. It is now demanded of using gas of Alaska and Siberia for long term developing the natural gas. The design of gas pipelines in Korea is very different from the arctic region. The operation of gas in arctic region have to consider of arctic region such as permafrost and active regions. It is needed to understand of gas pipeline design with different arctic soil properties. Nowadays, the pipelines is designed with stress-based and but there is demanded for strain based design with more deformed pipeline. We study of arctic environment with different active region using Finite Element Method of thermal elasto-plastic analysis.

Periventricular leukomalacia (PVL) is a common white matter lesion affecting the neonatal brain. PVL is closely associated with cerebral palsy (CP) and characterized by increase in the number of astrocytes, which can be detected by positivity for glial fibrillary acidic protein (GFAP). Change in myelin basic protein (MBP) is an early sign of white matter abnormality. Maternal or placental infection can damage the neonatal brain. In the present study, we investigated the effects of treadmill walking exercise on GFAP and MBP expressions in rats with maternal lipopolysaccharide (LPS)-induced PVL. Immunohistochemistry was performed for the detection of GFAP and MBP. The present results showed that intracervical maternal LPS injection during pregnancy increased GFAP expression in the striatum and decreased MBP expression in the corpus callosum of rats. The results also showed that treadmill walking exercise suppressed GFAP expression and enhanced MBP expression in the brains of rats with maternal LPS-induced PVL. The present study revealed that treadmill walking exercise is effective for the suppressing astrogliosis and hypomyelination associated with PVL. Here in this study, we showed that treadmill walking exercise may be effective therapeutic strategy for alleviating the detrimental effects of CP.

In the present study, we investigated the effects of maternal exercise before pregnancy on lipopolysaccharide (LPS)-induced hypomyelination and astrogliosis in neonatal rats. Female Sprague-Dawley rats (180 ± 10 g, 8 weeks old, n = 45) were used for maternal rats in this experiment. Before pregnancy, rats were randomly divided into three groups: the non-ex-control (CON) group, non-ex-LPS (LPS) group, and the Pre-ex-LPS (Ex-LPS) group (n = 15 in each group). The rats in the Ex-LPS group were forced to run on a motorized treadmill for 30 min once a day for 4 weeks. After the completion of exercise, all rats were allowed to mate with male rats for a period of 24 h. After conforming of pregnancies (n = 5 in each group), the maternal rats were treated with 0.15 mg/kg LPS and/or the same amount of pyrogen-free saline (PFS) on the 15th, 17th, and 20th day of pregnancy. The expression of Cyclooxygenasee-2 (COX-2) and Tumor necrosis factor-α (TNF-α) in brain was analyzed by RT-PCR. Immunohistochemistry for the glial fibrillary acidic protein (GFAP) and myelin basic protein (MBP) in the corpus callosum were conducted. In results, the expressions of COX-2, TNF-α and GFAP was significantly increased while the expression of MBP was significantly decreased in the neonatal rat brain of the LPS group compared to those of the CON group (p

The behavior of the load bearing capacity of a pipeline with unequal wall thickness was evaluated using finite element analyses. Pipelines with a wall thickness ratio of 1.22-1.89 were adopted to investigate plastic collapse under tensile, internal pressure, or bending stress. A parametric study showed that the tensile strength and moment of a pipeline with a wall thickness ratio less than 1.5 were not influenced by the wall thickness ratio and taper angle; however, those of a pipeline with a wall thickness ratio more than 1.5 decreased considerably at a low taper angle. The failure pressure of a pipeline with unequal wall thickness was not influenced by the wall thickness ratio and taper angle.

The purpose of this study was attempted to to identify the effects of combined resistance exercise and aerobic exercise course on health-related, and energy substrates. This study divided 24 healthy college students into the group of aerobic exercise after resistance exercise(n=8), the group of resistance exercise after aerobic exercise(n=8), and the control group(n=8) and thereby conducted a combined exercise program of different order for 12 weeks. Resistance exercise was conducted 4 times a week with the intensity of 60~70% of 1RM during the 1st through 8th week and the intensity of 70~80% of 1RM during the 9th through 12th week. Aerobic exercise was conducted 4 times a week with the intensity of 60~70% of maximum heart rate during the 1st through 8th week and the intensity of 70~80% of maximum heart rate during the 9th through 12th week. The results are as follows. 1. Changes of the health-related physical fitness In the changes of body composition through which we can know the degree of obesity. Body fat significantly decreased in both groups after 8 weeks and the decreased values were similar in each other group. However, the group of aerobic exercise after resistance exercise showed a significant increase of LBM after 8 weeks. We think that the method of aerobic exercise after resistance exercise was more effective than the other type of program. In the changes of physical fitness, flexibility, muscular endurance, muscular strength, and cardiovascular endurance of both exercised groups significantly increased compared to a control group. However, the increased values in both exercised groups showed similar results. 2. The changes of energy substrates There were no significant differences in glucose and free fatty acid being used by elements of energy substrates between the group of aerobic exercise after resistance exercise and the group of resistance exercise after aerobic exercise. Lactic acid, however, significantly decreased in the group of aerobic exercise after resistance exercise(0>12 weeks) and in the group of resistance exercise after aerobic exercise (0> 8, 12 weeks) compared to control group, respectively. Ultimately, this study provides evidence that the program which conducted aerobic exercise after resistance exercise is more effective than the program which conducted resistance exercise after aerobic exercise in the aspect of improving body composition. However, the both exercised groups showed a similar effect regardless of the order of execution of exercise in the elements of physical fitness and energy metabolism.

The objective of this study was to investigate the effect of the dent magnitude on the collapse behavior of a dented pipe subjected to a combined internal pressure and in-plane bending. The plastic collapse behavior and bending moment of the dented pipe containing several dent dimensions were evaluated using elastic–plastic finite element (FE) analyses. The indenters used to manufacture the dents on the API 5L X65 pipe were hemispherical rods with diameters of 40, 80, 160 and 320 mm. Dent depths of 19, 38, 76, 114 and 152 mm were introduced to the pipe with a diameter of 762 mm and a wall thickness of 17.5 mm. A closing or opening in-plane bending load was applied to the dented pipes pressurized under an internal pressure equivalent to atmospheric pressure as well as pressures of 4, 8, and 16 MPa. The FE analyses results showed that the plastic collapse behavior of the dented pipes was significantly governed by the bending mode and the dent geometry. Moment-bending angle curves for the dented pipe were obtained from computer simulations and evaluated with a variety of factors in the FE analyses. The load bearing capacity of the dented pipes under the combined load was evaluated by TES (Twice Elastic Slope) moments. The load bearing capacity of the pipe containing up to a 5% dent depth of the outer diameter was not reduced in comparison to that of the plain pipe. The opening bending mode had a higher load bearing capacity than the closing bending mode under the combined load regardless of dent depth. The TES moment decreased with increasing dent depth and internal pressure regardless of the bending modes.

The objective of this study was to investigate the effect of the thickness eccentricity on the collapse pressure of a subsea pipeline subjected to external pressure. The collapse behavior of the subsea pipeline containing initial imperfection was evaluated using elastic-plastic finite element (FE) analyses. API 5L X65 and API 5L X80 Pipelines with the thickness eccentricity values between 4~16% were adopted to investigate the plastic collapse under hydrostatic pressure. A parametric study was shown that the plastic collapse pressure decreased when either the thickness eccentricity or the ratio of diameter to thickness increased.

This paper proposes a new method to simulate ductile failure using finite element analysis based on the stress-modified fracture strain model. A procedure is given to determine the stress-modified fracture strain as a function of the stress triaxiality from smooth and notched bar tensile tests with FE analyses. For validation, simulated results using the proposed method are compared with experimental data for cracked bar (tensile and bend) tests, extracted from API X65 pipes, and for full-scale burst test of gouged pipes, showing overall good agreements. Advantages in the use of the proposed method for practical structural integrity assessment are discussed.

Medical X-ray has been brought many changes according to the rapid development of high technology. Especially, for high-voltage generator which is the most important in X-ray generation the traditional way is to use high-voltage electric transformers primarily. However, since it is large and heavy and the ripple rate of DC high-voltage applied to X-ray tube is too big, it has a disadvantage of low X-ray production efficiency. To solve these problems, the studies about high-voltage power supply are now proceeding. At present, the high-voltage generator that generates high-voltage by making high frequency using inverter control circuit consisting of semiconductor device is mainly used. High-voltage generator using inverter has advantages in the diagnosis using X-ray including high performance with short-term use, miniaturization of power supply and ripple reduction. In this study, the X-ray high-voltage device with inverter type using pulse width modulation scheme to the control of tube voltage and tube current was designed and produced. For performance evaluation of produced device, the control signal analysis, irradiation dose change and beam quality depending on the load variation of tube voltage and tube current were evaluated.

X-ray system which is usefully used in diagnosis of the patient, being bombed of radioactivity is a big weak point when irradiates a X-ray to the human body so that ICRP restricted the radiation exposure tolerance of the human body. In order to reduce being bombed, the many research and development is now advanced. A lots of diagnostic X-ray machines have currently used due to the increase of occurrence efficiency of X-ray and precisely the output control by using the inverter which is a high speed switching semiconductors. For getting the confidence of the X-ray machine, the same radiation occurrence, same evaluation, and same irradiation condition are necessary when evaluates X-ray irradiation. It is the most important part for the accuracy of the test result and the patient safety. This research has produced the high voltage occurrence system of full-wave rectification method by using the LC resonance inverter, and evaluated the irradiation reproducibility in order to use it in diagnosis of the patient.

A local failure criterion for API X65 steel is applied to predict ductile failure of full-scale API X65 pipes with simulated corrosion and gouge defects under internal pressure. The local failure criterion is the stress-modified fracture strain as a function of the stress triaxiality (defined by the ratio of the hydrostatic stress to the effective stress). Based on detailed finite element (FE) analyses with the proposed local failure criterion, burst pressures of defective pipes are estimated and compared with experimental data. For pipes with simulated corrosion defects, FE analysis with the proposed local fracture criterion indicates that predicted failure takes place after the defective pipes attain maximum loads for all cases, possibly due to the fact that the material has sufficient ductility. For pipes with simulated gouge defects, on the other hand, it is found that predicted failure takes place before global instability, and the predicted burst pressures are in good agreement with experimental data, providing confidence in the present approach.

A local failure criterion for the API X65 steel is applied to predict ductile failure of full-scale API X65 pipes with simulated corrosion and gouge defects under internal pressure. The local failure criterion is the stress-modified fracture strain for the API X65 steel as a function of the stress triaxiality (defined by the ratio of the hydrostatic stress to the effective stress). Based on detailed FE analyses with the proposed local failure criteria, burst pressures of defective pipes are estimated and compared with experimental data. The predicted burst pressures are in good agreement with experimental data. Noting that an assessment equation against the gouge defect is not yet available, parametric study is performed, from which a simple equation is proposed to predict burst pressure fur API X65 pipes with gouge defects.

This study aims to identify the visitor expenditure pattern and estimate the economic impact of the 2004 Boryeong Mud Festival. The average expenditure of food & beverage, shopping, transportation, accommodation, entertainment and the other costs were calculated based on the collected data. Among the five major categories, the accommodation expenditure was the highest followed by food & beverage, entertainment, transportation, and retail shopping. The retail shopping expenditure was found distinguishably low compared with that of other festivals or events sponsored by the Ministry of Culture & Tourism. Induced multipliers derived from Input-Output Analysis were adjusted and utilized for the sales (output) measure of economic impact. The economic impact on sales brought by the 2004 Boryeong Mud Festival was estimated at $33.3 million US dollar, which is almost 20 percent more than the previous year.

This study presents a probabilistic methodology for estimation of the remaining life of pressurized pipelines containing active corrosion defects. A reliability assessment was carried out using extreme value distribution of the corroded defects instead of the already published failure pressure model like NG18 or ASME B31G. The failure probability of pipelines depends on the number of corroded defects, and it was calculated directly as the area exceeded a defined LV(Limited Value of corrosion depth). The remaining life of pressurized pipelines can also be estimated by the PDF of extreme value distribution as calculating the exceeded area with a defined failure probability.

The failure assessment for the defects in multiple corroded region has been considered with the real-size pipeline burst tests and the associated Finite Element Method. The corroded gas pipeline made of X65 steel with various types of artificially machined pits has been used for a number of series of burst tests on gas pipeline. The failure pressures for the designed multiple corroded defect on gas pipelines have been measured by using in-situ burst testing and classified with respect to each designed defect sizes - length, width and depth - and distance between defects. The result from the experiments has been modeled and compared with Finite Element Method. As the result of FEM simulation, the failure pressure in multiple defects is lower than that in single defect, and closer to failure pressure in single defect of total length of defects in multiple defects as the distance between each defect is closer.

c-Fos has been used as a neuronal activity marker. Here, we examined the influence of age on the treadmill running-induced c-Fos expression in rat hippocampus. Rats of exercise groups were forces to run on treadmill for 30 min. once a day for 5 consecutive days. Without exercise, c-Fos expression was highest in 8-week old rats. Treadmill exercise significantly enhanced the c-Fos expression in the hippocampus of rats in all ages. In the CA region, the increase of the c-Fos expression by treadmill exercise was highest in 4-week old rats. In the dentate gyrus, the increase of the c-Fos expression by treadmill exercise was highest in 62-week old rats. The data show that age is an important factor for the regulation of the c-Fos expression in the hippocampus and that the ability of the treadmill exercise enhancing the c-Fos expression is dependent on age status.

Nitric oxide (NO) is a free radical synthesized from L-arginine by nitric oxide synthase (NOS). NO is crucially involved in the regulation of food intake and it is also closely implicated in the abnormalities of food intake such as hyperphagia. In the present study, the effects of treadmill exercise on the expressions of NOS and neuronal nitric oxide synthase (nNOS) in the hypothalamus of streptozotocin-induced diabetic rats were investigated. Sprague-Dawley rats were divided into four groups; the control-rest group, the control-exercise group, the diabetes-rest group, and the diabetes-exercise group. Rats in the exercise groups were put on the treadmill to run for 30 minutes once a day for 6 consecutive days. The results of the present study is that treadmill exercise suppressed diabetes-induced increase of NOS and nNOS expressions in the hypothalamus. These results suggest the possibility that treadmill exercise may reduce the increased appetite induced by diabetes.

Nitric oxide (NO) is synthesized from L-arginine by nitric oxide synthase (NOS). Alternation of NOS expression is implicated in the pathogenesis of numerous secondary complications of diabetes. Aqueous extract of Ginseng radix has traditionally been used for the various disorders including diabetes. In this study, the effect of Ginseng radix on the NOS expression in the hippocampus of streptozotocin (STZ)-induced diabetic rats was investigated via nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) histochemistry. Enhanced NOS expression was detected in the hippocampus of diabetic rats and administration of Ginseng radix suppressed NOS expression. Ginseng radix may aid the treatment of central nervous system complications in diabetes.

Diabetes mellitus is a common and serious metabolic disorder in humans. Streptozotocin (STZ)-induced diabetic rats were shown to produce a significant reduction in the number of proliferating cells in the dentate gyrus. In the present study, the effect of treadmill exercise on cell proliferation in the dentate gyrus of rats with STZ-induced diabetes was investigated via immunohistochemistry. Male Sprague-Dawley rats were divided into four groups: the control-rest group, the control-exercise group, the diabetes-rest group, and the diabetes-exercise group. Each of the animals of the diabetes groups was given a single injection of STZ (50 mg/kg) intraperitoneally. All animals were injected with 5-bromo-2'-deoxyuridine (50 mg/kg) for six consecutive days, starting on the second day after STZ injection, and rats of the exercise groups were made to run on treadmill for 30 min each day over the same period. On the eighth day of the experiment, all animals were sacrificed. In the present results, it was shown that cell proliferation in the dentate gyrus is suppressed under diabetic conditions, and that treadmill is effective in enhancing hippocampal granular cell proliferation in rats with STZ-induced diabetes. These results raise the possibility that treadmill exercise is of help in the alleviation of the central neural sequelae of diabetes mellitus.

In the present study, the effect of acupuncture at Zusanli acupoint on nitric oxide synthase (NOS) expression in the hippocampus of streptozotocin (STZ)-induced diabetic rats was investigated via nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) histochemistry. Animals were divided into four groups: the control group, the nondiabetic and acupunctured group, the STZ-induced diabetes group, and the STZ-induced diabetes and acupunctured group. From the results, NADPH-d-positive neurons in the hippocampus were decreased in STZ-induced diabetic rats, while acupuncture increased NOS expression significantly under diabetic conditions. In the present study, it can be suggested that acupuncture treatment may modulate NOS activity in the hippocampus under diabetic conditions.

The effects of forced treadmill exercise on cell proliferation and apoptosis in the hippocampal dentate gyrus in Sprague-Dawley rats were investigated. The animals were classified into three groups: the control group, the easy exercise group, and the moderate exercise group. In the control group, rats were left on the treadmill without running for 30 min per day, while rats in the exercise groups were made to run on the treadmill for the same duration. All rats were injected intraperitoneally with 5-bromo-2′-deoxyuridine (BrdU) one-hour prior to exercise once a day for 7 consecutive days beginning at the start of the exercise regimens. Each of the rats was sacrificed 2 h after the last exercise. Both the easy and moderate exercise groups revealed increased number of BrdU-positive cells in the dentate gyrus compared to the control group. The terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay revealed very few apoptotic cells, with no statistically significant differences among the groups. These results showed that treadmill exercise increases cell proliferation without altering of apoptosis in the dentate gyrus of the hippocampus.

In the present study, the effect of Ginseng radix on cell proliferation in the dentate gyrus of rats with streptozotocin-induced diabetes was investigated via immunohistochemistry. Aqueous extract of Ginseng radix was shown to exert no significant effect on weight in normal rats, while it prevented weight loss in rats with streptozotocin-induced diabetes. Cell proliferation in the dentate gyrus of diabetic rats was increased by Ginseng radix treatment, but it had no effect on cell proliferation in normal rats. These results suggest that Ginseng radix may help in improve the central nervous system complications of diabetes mellitus.

Utilization of panoramic X-ray device is getting wider. Panoramic X-ray has low resolution than general X-ray device and it occurs to distortion by deviation of image synthesis. Due to structural problems, it has been used restrictively to identify of tooth structure, not for whole head. Therefore, it designed and produced panoramic X-ray device which is possible to diagnostic coverage can be extended and had to be adjusted interval control between X-ray generator and image processing for whole of Maxillofacia's diagnosis. Produced panoramic X-ray device is composed basically of short image synthesis. In addition, it was confirmed the results by used the device which was applied deviation of the brightness of the image, filter to improve the location of the deviation and interpolation method. In this study, it was used 13 images including the front. It occurs to brightness deviation, position deviation, and geometric correction when synthesis of image, but it had been solved by deviation improvement software and a change of CCD camera's scan line which is used for image acquisition. Therefore, it confirmed expansion possibility of utilization range to commonly used panoramic X-ray device.

에너지 배관 건설에서 가장 핵심 부분은 배관 원주용 접이다. 배관과 배관을 연결하는 작업이 공사 진척도를 결정하기 때문에, 이를 얼마나 경제적으로 신속하게 신 뢰성을 확보하면서 수행하는 지 여부가 건설기간 및 건 설비용을 결정하는 핵심 요소이다. 가스배관 시공 원주 용접 방법은 수동, 반자동, 자동 등 여러 가지 있는데, 현재 국내에서는 완전 수동용접(SMAW) 공정을 채택 하고 있다. 이 방법은 국내 고압 가스배관을 건설한 초 기부터 적용해온 것으로, 우수한 품질을 확보할 수 있 으며 취약한 국내 자동화기술과 열악한 배관 시공여건 환경에서 적용하기 용이하기 때문에 현재까지 사용되고 있다. 그러나 우수한 용접기량을 보유한 용접사가 점차 부 족해지고, 국내 천연가스 미공급지역에서 가스배관 시 공이 동시다발적으로 진행되면서 가스배관 시공을 적기 에 완료하기 위해 시간을 단축하고 비용을 줄이는 방안 이 필요한데, 이를 해결할 수 있는 기술이 자동원주용 접방안이다. 이 기술들은 해외 가스배관에 다양한 방법 으로 적용되어 용접부위 신뢰성과 품질 우수성을 확보 하고 시공비용절감을 달성하고 있다. 자동용접을 적용 하기 위해서는 용접절차를 수립하여 절차인증시험을 수 행하여 기존 방안과 동등 이상 품질이 확보되고 효율성 이 겸비됨을 검증해야만 한다. 가스배관 시공은 국가 기본에너지의 안정적인 공급을 위해 적기 시공이 필요하다. 또한 1 km당 10 억 원 이상이 소요되는 배관시공비용 중 약 1/3이 용접비파 괴검사 비용인 점을 감안할 때 품질이 확보되면서 경제 적인 시공방안이 있다면 이를 적용하는 것이 국가 산업 경제적 측면에서도 필요한 일이다. 이와 관련된 국내 가스배관 원주용접에 적용 가능한 자동용접 공정을 검토하고, 용접절차를 수립하여 절차 인증시험을 수행하였으며, 추가로 배관 원주 자동용접 부위에 대한 기계적 특성 평가를 실시하였다. 본 자료 에서는 자동용접 공정개발 과정과 원주용접부위 기계적 특성을 검토한 결과를 요약하였다.