• Title/Summary/Keyword: Bearing Number

Search Result 652, Processing Time 0.025 seconds

Incubation Time Required for Hatching, and Ecological Characteristics of the Mode of Life Related with Total Numbers of the Suckers on Each Short Arm of the Hatched Juvenile Larvae of Octopus ocellatus (Cephallopoda: Octopodidae), in Western Korea

  • Kim, Sung Han;Jun, Je-Cheon
    • The Korean Journal of Malacology
    • /
    • v.32 no.2
    • /
    • pp.133-139
    • /
    • 2016
  • The incubation time required for hatching of O. ocellatus were investigated through the processes of egg and embryonic developments by the dissecting microscopic and visual observations. And differences in ecological characteristics of the plankton mode of life or the benthic mode of life according to total numbers of the suckers on each short arm of the hatched juvenile larvae of O. ocellatus were studied by comparisons with other octopodidae species. Compared with the recent a few results reported by other researchers associated with the incubation time required for hatching by female adult mother of O. minor (73-90 days after spawning at $20.9-21.5^{\circ}C$ ranges), in this study, the incubation time required for hatching by female adult mother of O. ocellatus was 56-57 days after spawning at $11.0-20.4^{\circ}C$. Therefore, the incubation time required for hatching by female adult mother varied with Octopodidae species. In this studies, each ovarian egg laid by a female was connected to an egg string attaching to the surface of the wall or bottom of vacunt shell of Rapana venosa. Egg and embryonic developments of this species were studied in the indoor aquaria, in the specific gravity ranging 1.024-1.025. the hatched juvenile of O. ocellatus is 10.3 mm in the mean total length and 4.5 mm in mantle length, and each of its short arms has 18-20 suckers. The just hatched juvenile larvae of O. ocellatus enter the benthic mode of life (benthic larval stage) after hatching. In particular, regarding differences in ecological characteristics of the mode of life according to total numbers of the suckers, O. vulgaris may not need to have many suckers because they enter the planktonic mode of life after hatching, however O. ocellatus may need to have many suckers, because they should adapt to the benthic mode of life. And also the just hatched juvenile larvae of O. minor (bearing many suckers more than O. ocellatus) enter the benthic mode of life (benthic larval stage) after hatching. Therefore, the total number of the suckers on each short arm of the hatched juvenile larvae can be used for determining whether an octopus species has planktonic larval stages or benthic larval stage (benthic mode of life). In particular, The intracohort cannibalism phenomena appeared at the hatched juvenile larval stage because the larval stage of O. ocellatus and O. minor enter into the benthic larval stage in the early stage, unlike entering into the plaktonic larval stage in other Octopus species such as O. vulgaris: at this time, the early hatched larvae fed the late hatched larvae (they are the same species and almost same ages). Therefore, the intracohort cannibalism pheneomena occur in the just hatched juvenile stage of only O. ocellatus and O. minor.

Derivation and verification of electrical resistivity theory for surrounding ground condition prediction of TBM (TBM 주변 지반상태예측을 위한 전기비저항 이론식 유도 및 검증)

  • Hong, Chang-Ho;Lee, Minhyeong;Cho, Gye-Chun
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.22 no.1
    • /
    • pp.135-144
    • /
    • 2020
  • Since the depth of tunneling with tunnel boring machine (TBM) becomes deeper and deeper, the expense for site investigation for coring and geophysical survey increases to obtain the sufficient accuracy. The tunnel ahead prediction methods have been introduced to overcome this limitation in the stage of site investigation. Probe drilling can obtain the core and borehole images from a borehole. However, the space in TBM for the probe drilling equipment is restricted and the core from probe drilling cannot reflect the whole tunnel face. Seismic methods such as tunnel seismic prediction (TSP) can forecast over 100 m ahead from the tunnel face though the signal is usually generated using the explosive which can affect the stability of segments and backfill grout. Electromagnetic methods such as tunnel electrical resistivity prospecting system (TEPS) offer the exact prediction for a conductive zone such as water-bearing zone. However, the number of electrodes installed for exploration is limited in small diameter TBM and finally the reduction of prediction ranges. In this study, the theoretical equations for the electrical resistivity survey whose electrodes are installed in the face and side of TBM to minimize the installed electrodes on face. The experimental tests were conducted to verify the derived equations.

The Study on Modification Methods of Residents Registration Number System (재가방문 요양보호사의 대인관계스트레스가 이직의도에 미치는 영향 - 소진의 매개효과 검증)

  • Lee, Youn-Suk;Park, Kyung-il
    • The Journal of the Korea Contents Association
    • /
    • v.16 no.11
    • /
    • pp.369-383
    • /
    • 2016
  • This study aims for strengthening the ability of home visiting care giver by figuring out interpersonal stress of bearing hardships which affect turnover intentions of home visiting care givers and by focusing on mediating effect of burnout. First, in summary, the analysis result was that the age of care givers and the presence of spouse are in relational factors correlated with burnout. Also age and experience of turnover have some connection with turnover intentions. Second, interpersonal stress of burnout and turnover intentions have static correlation. Third, the interpersonal stress represents increasing level of stress of burnout and the intervention of burnout shows static effects on turnover intentions of care givers. Suggestions of this study's results are, first, solution of interpersonal stress which home visiting care givers are facing should be improved by families' support or encouragement. In addition, the more professional and organized job training should be advanced to improve the understanding of various situations and coping skills. Second, the more interest should be need on business characteristics and environmental limitation. Also many centers that support care givers should reinforce their role. Third, to decrease the turnover intention which comes from interpersonal stress, doing some burnout research could be helpful and especially the legal regime which supports the research of burnout is essential.

Effects of Gunleetang Gagambang Extract on Antitumoral Immunological Response and the Side Effect Induced by Antitumoral Agents (군리탕가감방(君理湯加減方)이 항종양(抗腫瘍) 면역반응(免疫反應)과 항암제로 유발(誘發)한 부작용(副作用)에 미치는 영향(影響))

  • Yui, Guyng-Tea;Moon, Suk-Jae;Moon, Goo;Won, Jin-Hee
    • THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
    • /
    • v.4 no.1
    • /
    • pp.71-87
    • /
    • 1998
  • Even though appropriate immune response is necessary for the survival of the individual, excessive or insufficient immune Response might cause autoimmune or allergic disease. So the immune response must be controlled to the degree that is beneficial for the well being of the individual. This study was undertaken to know the effects of Gunleetang Gagambang on the immune system of the mouse. Gunleetang Gagambang has been used for cure of tumor as a traditional medicine without any experimental evidence to support the rational basis for its clinical use. This study was carried out to evaluate the possible therapeutic or antitumoral effects of Gunleetang Gagambang extract against tumor, and to carry out some mechanisms responsible for its effect. Some kinds of tumor were induced by the typical application of 3-methylcholanthrene(MCA) or by the implantation(s.c) of malignant tumor cells such as leukemia cells(3LL cells) or sarcoma cells(S180 cells). Treatment of the Gunleetang Gagambang on water-extract(dailly 1mg/mouse, i. p.) was continued for 7 days prior to tumor induction and after that the treatment was lasted for 20 days. Against squamous cell carcinoma induced by MCA, Gunleetang Gagambang decreased not only the frequency of tumor production but also the number and the weight of tumors per tumor bearing mice(TBM). Gunleetang Gagambang on also significantly suppressed the development of 3LL cell and S180 cell-implanted tumors in occurrence-frequency and their size. and some developed tumors were regressed by the continuous treatment of Gunleetang Gagambang extract into TBM. In vitro, treatment of Gunleetang Gagambang extract had no effect on the growth of some kinds of cell line such as FsaII, A431 strain but significantly inhibited the proliferation of 3LL, S180 cells and augmented the DNA synthesis of mitogen-activated lymphocytes. Gunleetang Gagambang also stimulated the migrative ability of leukocyte, the MIF and IL-2 production of T lymphocytes, but not IL 6 production of B cells. Gunleetang Gagambang administration to mice enhanced NK cells activities. These results demonstrated that Gunleetang Gagambang extract exhibited a significant prophylactic benefits against tumors and its antitumor activity was manifested depending on the type of tumor cells. And these results also suggested that effect of Gunleetang Gagambang might be chiefly due to nonspecitie enhancement of NK cell activities and cell-mediated immune responses.

  • PDF

Perfect stage of Microsphaera polygoni (DC.) Sawada on Robinia pseudoacasia and its phylogenetic relationship to Gen Erysiphe (아카시아흰가루병균(病菌)의 완전시대(完全時代) 및 Erysiphe 속(屬)과의 계통관계(系統關係))

  • Kim, Ki Chung
    • Journal of Korean Society of Forest Science
    • /
    • v.9 no.1
    • /
    • pp.81-86
    • /
    • 1969
  • In present paper, the morphological characters in perfect stage of Microsphaera polygoni(DC.) Sawada on Robinia pseudoacasia were investigated and the phylogenetic relationship between Gen. Erysiphe and Microsphaera was discussed with variation of appendages. The results are summarized as follows: 1. The perithecia of the powdery mildew fungus on Robinia pseudoacasia were rarely formed on the surface of the leaves just before difoliation in late autumn and their forming period was very short. 2. Powdery mildew fungus on R. pseudoacasia was identified as Microsphaera polygoni(DC.) Sawada in Korea. 3. Appendage of the fungus are both Erysiphe and Microsphaera types in shape, and plenty of intercalary types are intervened between both types. Number of perithecia bearing upper various appendages appears the normal distribution with both poles of typical Erysiphe and Microsphaera types 4. If Blumer's theory on the phylogenetic relationship of Erysiphaceae is right, variation of the appendages of the fungus might be evolved from Gen. Erysiphe to Gen. Microsphaera.

  • PDF

Prediction Model for Reduced Bone mass in Women using Individual Characteristics & Life Style Factors (여성의 개인적 특성과 생활양식요인을 이용한 골량감소 예측모형)

  • Lee, Eun-Nam;Lee, Eun-Ok
    • Journal of muscle and joint health
    • /
    • v.5 no.1
    • /
    • pp.83-109
    • /
    • 1998
  • This study was carried out to identify the Important modifiable risk factors for reduced bone mass and to construct prediction model which can classify women with either low or high bone mass. Through the literature review, individual characteristics such as age, body weight, height, education level, family history, age of menarche, postmenopausal period, gravity, parity, menopausal status, and breast feeding period were identified and factors of life style such as past milk consumption, past physical activity, present daily activity, present calcium intake, alcohol intake, cigarette smoking, coffee consumption were identified as influencing factors of reduced bone mass in women. Four hundred and eighty women aged between 28 and 76 who had given measurement bone mineral density by dual energy x-ray absortiometry in lumbar vertebrae and femur from July to October, 1997 at 4 general hospitals in Seoul and Pusan were selected for this study. Women were excluded if they had a history of any chronic illness such as rheumatoid arthritis, diabetes mellitus, hyperthroidism, & gastrointestinal disorder and any medication such as calcium supplements, calcitonin, estrogen, thyroxine, antacids, & corticosteroids known affect bone. As a result of these exclusion criteria, four hundred and seventeen women were used for analysis. Multiple logistic regression model was developed for estimating the likelihood of the presence or absence of reduced bone mass. A SAS procedure was used to estimate risk factor coefficient. The results are as follows For lumbar spine, the variables significant were age, body weight, menopause status, daily activity, past milk consumption, and past physical activity(p<0.01), while for femoral Ward's triangle, age, body weight, level of education, past milk consumption, past physical activity(p<0.001). Past physical activity, present daily activity and past milk consumption are the most powerful modifiable predictors in vertebrae and femur among the predictors. When the model performance was evaluated by comparing the observed outcome with predicted outcome, the model correctly identified 74.1% of persons with reduced bone mass and 84.5% of persons with normal bone mass in the lumbar vertebrae and 82.9% of persons with reduced bone mass and 75.0% of persons with normal bone mass in the femoral Ward's triangle. On the basis of these results, a number of recommendations for the management of reduced bone mass may be made : First, those woman who are classified as high risk group of the reduced bone mass in the prediction model should examine the bone mineral density to further examine the usefulness of this model. Second, the optimal amount of milk consumption and a regular weight bearing exercise in childhood, adolescence, and early adult should be ensured.

  • PDF

A Study on the Characteristics of High-Tension Bolted Joints' Behavior due to Surface Condition (표면상태에 따른 고장력볼트 마찰이음부의 거동특성에 관한 연구)

  • Cho, Sun Kyu;Hong, Sung Wook
    • Journal of Korean Society of Steel Construction
    • /
    • v.9 no.3 s.32
    • /
    • pp.421-430
    • /
    • 1997
  • In this study, the static and the fatigue tests were performed with high tension bolted joints, of which the surfaces were spread with inorganic zinc-primer after shot-blast, and milling surface, and steel-natural surface, difference of friction surface condition were examined by comparing the esults of tests. From the result of synthetical investigation of this study. it is proper that using the torque management method in order to introduce design axial force to blots, and the provision of specifications that initial axial forces must be 110% of design axial forces is proper. Decreasing ratio of axial forces to initial force is proportional to common lorgarithms of time progress, it converge constant value after 20 hours, and decreasing ratio is little related to the roughness of friction surface. Sliding coefficient of milling, spreading inorganic zinc-primer, just producting is great in order and sliding forces are dependent on the applied axial forces, but if the applied axial forces are great, sliding coefficient become small by a loss of roughness. So it is confirmed that relation between the applied axial forces and the sliding forces are not proportional linearly. From the result of estimation on fatigue strength, all specimens satisfy the specifications with B-grade and milling surface is lower than the others about 14% in fatigue strength because in milling surface lose the function of friction-types joints at lower number of cycles. From the result of eximination for the distribution area of compressive force, friction area near to inside bolt is wider in the direction of stress than near to outside. It is guessed that this situation occurs because outside bolts firstly change from the friction connection to the bearing connection.

  • PDF

Tumor-Derived Transforming Growth Factor-β is Critical for Tumor Progression and Evasion from Immune Surveillance

  • Li, Zheng;Zhang, Li-Juan;Zhang, Hong-Ru;Tian, Gao-Fei;Tian, Jun;Mao, Xiao-Li;Jia, Zheng-Hu;Meng, Zi-Yu;Zhao, Li-Qing;Yin, Zhi-Nan;Wu, Zhen-Zhou
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.13
    • /
    • pp.5181-5186
    • /
    • 2014
  • Tumors have evolved numerous mechanisms by which they can escape from immune surveillance. One of these is to produce immunosuppressive cytokines. Transforming growth factor-${\beta}$(TGF-${\beta}$) is a pleiotropic cytokine with a crucial function in mediating immune suppression, especially in the tumor microenvironment. TGF-${\beta}$ produced by T cells has been demonstrated as an important factor for suppressing antitumor immune responses, but the role of tumor-derived TGF-${\beta}$ in this process is poorly understood. In this study, we demonstrated that knockdown of tumor-derived TGF-${\beta}$ using shRNA resulted in dramatically reduced tumor size, slowing tumor formation, prolonging survival rate of tumor-bearing mice and inhibiting metastasis. We revealed possible underlying mechanisms as reducing the number of myeloid-derived suppressor cells (MDSC) and $CD4^+Foxp3^+$ Treg cells, and consequently enhanced IFN-${\gamma}$ production by CTLs. Knockdown of tumor-derived TGF-${\beta}$ also significantly reduced the conversion of na$\ddot{i}$ve $CD4^+$ T cells into Treg cells in vitro. Finally, we found that knockdown of TGF-${\beta}$ suppressed cell migration, but did not change the proliferation and apoptosis of tumor cells in vitro. In summary, our study provided evidence that tumor-derived TGF-${\beta}$ is a critical factor for tumor progression and evasion of immune surveillance, and blocking tumor-derived TGF-${\beta}$ may serve as a potential therapeutic approach for cancer.

KNEE: Basic Science and Injury of Bone (슬관절 주위 글격의 기초과학 및 스포츠 손상)

  • Kim Hee-Chun
    • Journal of Korean Orthopaedic Sports Medicine
    • /
    • v.2 no.2
    • /
    • pp.77-81
    • /
    • 2003
  • Purpose: The biomechanics and kinematics of knee joint were reviewed in this article. And then the common sports injuries were presented. Anatomy and Kinetics: None of the pairs of bearing surfaces in the knee joint is exactly congruent This allows the knee six degrees of freedom of motion. Tibiofemoral Kinematics: In flexion and extension, the axis of motion is not perpendicular to the medial-lateral plane of the joint, nor is it perpendicular to the axis of longitudinal rotation. This results in coupled varus angulation and internal rotation with flexion and in valgus angulation and external rotation with extension. Patellofemoral Articulation: Loads across the patellofemoral joint are indirectly related to the angle of knee flexion and directly related to the force generated within the quadriceps mechanism. Fractures of the Patella: Nonoperative treatment is indicated if the extensor mechanism is intact and if displacement of fragment is minimal. The specific type of internal fixation depends on the fracture pattern. It is important to repair retinaculum. Acute and Recurrent Patellar Instability: The degree of dysplasia and the extent of the instability play a large part in determining the success of nonoperative treatment. Patients who experience recurrent dislocations and patients with major anatomic variations require surgery to minimize their instability. Sports Injuries in School-age Atheletes: Patellar pain in young athletes groups a number of conditions, including Idiopathic Adolescent Anterior Knee Pain, Osgood- Schlatter Disease, and Sinding-Larsen-Johansson Disease.

  • PDF

Experimental Study on the Load Transfer Behavior of Steel Grid Composite Deck Joint (격자형 강합성 바닥판 이음부의 하중전달 거동에 관한 실험적 연구)

  • Shin, Hyun-Seop
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.18 no.4
    • /
    • pp.10-21
    • /
    • 2014
  • The joint of prefabricated steel grid composite deck is composed of concrete shear key and high-tension bolts. The flexural and shear strength of the joint were experimentally evaluated only by the bending and push-out test of the joint element. In this study the lateral load transfer behavior of the joint in deck structure system is experimentally evaluated. Several decks connected by the joint are prefabricated and loaded centrically and eccentrically. In the case of centrically loaded specimens, the analysis results show that for the same loading step the rotation angle of the joint with 4 high-tension bolts is larger than the case of the joint with 9 high-tension bolts. Consequently, flexural stiffness of deck and lateral load transfer decrease in the case of specimen with 4 high-tension bolts. But, in the case of eccentrically loaded specimens, it is found that there are no significant differences in the load transfer behavior. The further analysis results about the structural behavior of the joint show that lateral load transfer can be restricted by the load bearing capacity of the joint as well as punching shear strength of the slab. Furthermore, considering that high-tension bolts in the joint didn't reach to the yielding condition until the punching shear failure, increase in the number of high-tension bolts from 4 to 9 has a greater effect on the flexural stiffness of the joint and deck system than the strength of them.