목적 : 운동학습은 신체적인 연습과 경험의 결과로 동작에 대한 기술 습득의 과정으로 표현된다. 최근 정신적 훈련을 통해 운동 기술의 습득이 이루어질 수 있다는 연구가 많이 보고되고 있다. 본 연구는 시열반응과제를 통하여 실제 훈련과 정신 훈련의 효과에 대해 연구하고자 하였다. 연구방법 : 50명의 정상 성인을 대상으로 정신 훈련군, 실제 훈련군, 대조군으로 무선적 배치하였다. 측정된 시열반응과제는 컴퓨터 화면에 제시되는 네 가지의 색깔에 대응하는 반응패드를 손가락을 이용하여 최대한 빨리 정확히 누르도록 하고, 반응 시간을 측정하였다. 정신 훈련군과 실제 훈련군은 정신 및 실제 훈련을 하루 30분, 2주 동안 훈련하였고, 훈련 시간은 동일하게 설계하였다. 결과 : 이요인 반복 측정 공분산 분석의 집단 간의 주 효과 검정에서 통계학적으로 유의한 차이가 관찰되었으며, 집단×훈련 전·후 간의 상호작용에서도 유의한 차이가 관찰되었다(p<.05). 또한 사후 검정에서 정신 훈련군과 대조군, 실제 훈련군과 대조군에서 유의한 차이를 보였다(p<.05). 이러한 결과는 훈련 후 대조군에서의 시간의 감소보다 정신 훈련군과 실제 훈련군에서의 과제 수행 시 시간의 감소가 더 크게 나타났다. 결론 : 본 연구에서는 정신 훈련군에서 실제 훈련군과 같이 운동 학습의 효과가 나타났으며, 정신 훈련은 효과적인 운동학습을 위한 방법임이 입증되었다. 그러므로 운동제어와 인지학습을 시켜야 하는 재활 영역에서 뇌손상 환자에게 학습을 시키기 위한 방법으로 정신 훈련을 채택할 수 있으며, 마비측의 실제 훈련을 수행하기에 어려운 상황에서는 정신 훈련이 더 효과적일 수 있고, 실제 훈련과 비슷한 효과를 기대할 수 있을 것으로 생각된다.

Aging causes thymus involution, and genes in thymus play an important role in the development of the immune system. In this study, we compared genes expressed in thymus of neonatal and peripubertal rats using annealing control primers (ACPs)-based GeneFishing polymerase chain reaction (PCR) and semiquantitative reverse transcription (RT)-PCR. We identified 10 differentially expressed genes (DEGs) with 20 ACPs. Of 10 DEGs, bystin-like, collagen type V alpha 1 (COL5A1), and T-cell receptor beta-chain segment 2 (TCRB2) that are related to immune-function were detected in rat thymus. Bystin-like and TCRB2 were up-regulated, while COL5A1 was down-regulated in peripubertal thymus. Semiquantitative RT-PCR confirmed postnatal changes in expression of bystin-like, COL5A1, and TCRB2. These results suggest that bystin-like, COL5A1, and TCRB2 could regulate immune function controlled in thymus as age increases.

The purpose of this study was to observe the histopathologic tissue reaction in vital bone in applying the various treated implants. For this purpose, twelve New Zealand Albino rats, weighing 3.3 to 4 kg were used as experimental animals. All the experimental groups divided into four groups; Machined surface as control, RBM(resorbable blast media), Hydroxyapatite-sand and Porous coating groups. All the experimental implants were examined under the scannning electron microscope. All the experimental rabbits were implanted in the tibial metaphyses of rabbits under the general anesthesia with Ketamine HCl(2.5ML /kg.body wt.) injections. For prevention of infection after implant, prophylactic erythromycine injections, 250mg/body wt.(Aldrich Co. USA) were performed on each. On the sixth week after implant, all the experimental rabbits were sacrificed with over dose of Sedaject(Samwoo Pharm .Co. Korea). All the tissues containing each experimental materials were fixed in ethyle alcohol, and embedded in spurr resin(Polytechnic Co. USA) as usual manner. sectioned in 12 um thickness, grinded , stained with the Vulenueva's osteochrome stain methed and examined histopatholgically. For measuring the distances between the implant and bone without any connective tissue interface, all the distances were calculated the length of the implant direct contact to bones. using the view analyzer program( Korea Optical Co.) and the statistical analysis were performed using the one-way ANOVA test. The statistical differences were considered significant below 5% level. Following results were obtained. On the scanning electron microscopic examination, dull cracked continuous linear indentations were revealed on the machined surface implant, irregular sharp indentation on the resorbabale blast, irregular thin exophytic or indentated leaflets on the hydroxyapatite-sand implant, and long ovoid globular particles were revealed on the porous coating implant surface respectively. On the histopathologic examination, complete osseointegation was noted between the implant and cortex bone on the collar and the apex lesion and in parts, small newley formed bone spicules attached to the screws in marrow tissues with compatibility in all experimental groups, but on the aspect of the tissue compatibility to the various implant materials, the superiority of the materials could not identified. The ratio of drect contact between the bone and implant, the HA sand gorup was the most superior among the gorups and followed by the machine surface, but on RBM and porous coating groups were inferior compared to that on the experimental groups. With these results, the superiority of tissue compatibility among the experimental implant group could not be identified

목적 : 편마비 환자에서 손상된 대뇌반구의 동측은 정상으로 인식되었으나 운동장애가 있음이 보고되고 있다. 본 연구는 편마비 환자의 동측 상지를 이용한 연속반응시간과제에서 동측운동결함 여부를 정상군과 비교 관찰하였다. 연구방법 : 편마비 환자 18명(오른쪽 편마비 10명, 왼쪽 편마비 8명)을 대상으로 손상된 대뇌반구의 동측 손가락을 이용한 연속반응시간과제를 수행하는 동안 환자군과 연령과 성별이 일치하는 정상군 18명과 비교하여 반응시간을 분석하였다. 연속반응시간과제는 구획설계와 무작위설계로 구성하였고 자극은 4가지 색깔(빨강, 노랑, 초록, 파랑)의 원모양이 하나씩 연속적으로 컴퓨터 모니터에 제시되었고, 연구대상자는 일련의 자극과 색깔이 일치하는 반응패드의 버턴을 가능한 빠르고 정확하게 누르도록 하여 반응시간을 측정하였다. 각 설계단위 당 10회 반복하는 것을 1블록으로 설정하여 총 3블록을 수행하였고, 수집된 자료는 이원분산분석으로 통계 처리하였다. 결과 : 구획설계와 무작위설계 모두에서 집단간 주효과 검증결과 집단 간에는 통계학적으로 유의한 차이가 관찰되었다(p<0.001). 그러나 오른손·왼손간 주효과 검증결과 및 집단×왼쪽·오른쪽간 상호작용에는 통계학적으로 유의한 차이가 관찰되지 않았다(p>0.001). 결론 : 환자군에서 연속반응시간과제의 반응시간이 정상군보다 느리게 나타나 편측 대뇌반구 손상으로 인한 편마비 환자의 동측 상지에 동측운동결함이 발견되었다.

In this investigation, based ceramic composites were fabricated by in-situ reaction hot pressing using , TiC SiC powder as starting materials. The reaction synthesized composites by hot pressing at was found to posses very high relative density. The reaction synthesized composites comprise , , SiC and graphite by the reaction between TiC and . The newly formed and graphite was embedded both inside grain and at grain boundary . The mechanical properties of reaction synthesized -graphite composites were more enhanced compared to those of monolithic .

Theoretical framework of motor learning is used to enhance perceptual motor skill in physical therapy intervention, which can be subdivided into two main types-explicit and implicit. The purpose of this study was to examine whether stroke patients with unilateral brain damage learn implicitly a motor skill using the arm ipsilateral to the damaged hemisphere. Speculation then followed as to the formation of therapeutic plans and instructions provided to patients with stroke. 20 patients with stroke and 20 normal participants were recruited. All the subjects practiced serial reaction time tasks for 30 minutes a day and retention tests on the following day. The tasks and tests involved pressing the corresponding buttons to 4 colored circles presented on a computer screen as quickly and accurately as possible. Patients with stroke responded more slowly than controls. However, both groups showed decreased reaction time in the experimental and retention periods. Also, there was no significant difference between both groups regarding explicit knowledge of consecutive order. Therefore, patients with stoke had the ability to learn implicitly a perceptual motor skill. Prescriptive instruction using implicit and explicit feedback may be beneficial for motor skill learning in physical therapy intervention for patients with brain damage.

The purpose of this study was to assess the influence of spine orthosis and sit-to-stand motor strategies on ground reaction force (GRF) and lower extremity muscle activity. Twenty healthy adult men participated, and subjects randomly performed sit-to-stand motions in three different conditions: Momentum-transfer strategy (MTS); MTS with spine orthosis; and zero-momentum strategy (ZMS) with spine orthosis. GRF data, onset time, and muscle activity were determined and compared using force plate and electromyography. Data were statistically analyzed by the SPSS version 13.0. One-way repeated analysis of variance (ANOVA) was used to determine the statistical significance, and least significant difference was used as a post hoc test. The level of significance was .05. The results of this study were as follows: 1. Peak GRF and relative time to peak GRF were not significantly different in the three different conditions (p>.05). 2. Onset time of four muscles, tibialis anterior, gastrocnemius, biceps femoris and rectus femoris, in the three different conditions were significantly different (p<.05). 3. The tibialis anterior and rectus femoris muscle activity before hip-off and tibialis anterior, gastrocnemius, and rectus fermoris muscle activity after hip-off were significantly different in the three different conditions (p<.05).

Yttrium aluminum garnet (YAG) powders were synthesized via mechanochemical solid reaction using with three types of aluminum compounds. reacted mechanochemically with all A1 compounds and formed YAM (yttrium aluminum monoclinic), YAG and YAP (yttrium aluminum perovskite) phases depending on the starting materials. The ground samples containing showed the best reactivity, whereas the ground sample containing A100H, which had the largest surface area, exhibited pure YAG after calcination at . The sample containing Al had the least reactivity, producing YAP along with YAG at . The types and grinding characteristics of the starting materials and grinding time are believed to be important factors in the mechanochemical synthesis of YAG.

Muscle weakness in the hemiplegia following stroke is an important factor which determines the quality of life in the future. Therefore, muscle strengthening exercise is essential for functional recovery in hemiplegic patients. Even though the popular conception is that muscle strengthening exercise causes spasticity and associated reaction that hemiplegia patients don't want, and that it disturbs functional recovery, recently there have been many new reports against that opinion. Therefore, the effects of strengthening exercise programs on functional recovery in hemiplegic patients are still controversial. The purpose of this study was to determine the effects of strengthening exercise programs for the knee joint using isokinetic exercise on the associated reaction of the upper extremities. Comparing the muscle activities of biceps brachii and triceps brachii during, before, and immediately after 2 and 5 minute intervals of isokinetic exercise, we examined the increase and decrease of associated reaction. Twenty stroke inpatients participated in this study. Surface electromyography was used to get muscle activity data from biceps brachii and triceps brachii. The major findings of this study were as follows: 1. The flexor and extensor peak torque were significantly higher on the sound side than the affected side (p<.05). 2. Before and after strengthening exercise, there was no significant difference in muscle activities (surface electromyographic root mean square values) between the sound and affected side. 3. Muscle activities were examined during, before, and immediately after 2 and 5 minute intervals of isokinetic exercise. There were significant differences in muscle activities between, before and during the exercises, during exercise and 5 minutes after exercise in the biceps brachii (p<.05), and during exercise and 5 minutes after exercise in the triceps brachii (p<.05). In conclusion, there was no relation between strengthening exercise and associated reaction in the upper extremities. Rather, muscle activities after exercise had a tendency to decrease relative to before the exercise. Thus, it is considered that intensive strengthening exercise contributes to improvement of functional recovery without increase in associated reaction in hemiparetic patients.

In the present study, the focus is on the synthesis of nanosized WC powder by the chemical vapor condensation proces. The synthesized W-C system powder by the CVC process shows W2C, W, WO3 phases and can not shows WC phase. After recarburization heat treatment under mixture gas atmosphere of argon and hydrogen gases, the synthesized W-C system powder fully transformed to the pure WC. The synthesized WC powder after recarburization heat treatment has an average particle size of 20 nm. The nano-sized WC powder can be prepared by the combination of the CVC process and heat treatment methods.

Monodispersed and nano-sized Ni powders were synthesized from aqueous nickel sulfate hexahydrate inside nonionic polymer network by using wet chemical reduction process. The sucrose was used as a nonionic polymer network source. The effect of reaction conditions such as the amount of sucrose and a various reaction temperature, nickel sulfate hexahydrate molarity. The influence of a nonionic polymer network on the particle size of the prepared Ni powders was characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), and particle size analysis (PSA). The results showed that the obtained Ni powders were strong by dependent of the reaction conditions. In particular, the Ni powders prepared inside a nonionic polymer network had smooth spherical shape and narrow particle size distribution.

We have demonstrated that textured nanocomposites can be fabricated by slip casting followed by partial oxidation. reaction sintering of mixed suspensions of and SiC powders in a high magnetic field. The sintered density was changed by the degree of oxidation at 1200C and 1300C. The degree of orientation of alumina in the nanocomposite was examined on the basis of the X-ray diffraction patterns and scanning electron micrographs. It is confirmed that aluminaoriented nanocomposites were fabricated. The three-point bending strength at room temperature was observed for the nanocomposites.

We have demonstrated that textured nanocomposites can be fabricated by slip casting followed by partial oxidation - reaction sintering of mixed suspensions of and SiC powders in a high magnetic field. The sintered density was changed by the degree of oxidation at 1200C and 1300C. The degree of orientation of alumina in the nanocomposite was examined on the basis of the X-ray diffraction patterns and scanning electron micrographs. It is confirmed that alumina-oriented nanocomposites were fabricated. The three-point bending strength at room temperature was observed for the nanocomposites.