• Title/Summary/Keyword: description mechanism

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Chronic Subdural Hematoma in the Aged, Trauma or Degeneration?

  • Lee, Kyeong-Seok
    • Journal of Korean Neurosurgical Society
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    • v.59 no.1
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    • pp.1-5
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    • 2016
  • Chronic subdural hematomas (CSHs) are generally regarded to be a traumatic lesion. It was regarded as a stroke in 17th century, an inflammatory disease in 19th century. From 20th century, it became a traumatic lesion. CSH frequently occur after a trauma, however, it cannot occur when there is no enough subdural space even after a severe head injury. CSH may occur without trauma, when there is sufficient subdural space. The author tried to investigate trends in the causation of CSH. By a review of literature, the author suggested a different view on the causation of CSH. CSH usually originated from either a subdural hygroma or an acute subdural hematoma. Development of CSH starts from the separation of the dural border cell (DBC) layer, which induces proliferation of DBCs with production of neomembrane. Capillaries will follow along the neomembrane. Hemorrhage would occur into the subdural fluid either by tearing of bridge veins or repeated microhemorrhage from the neomembrane. That is the mechanism of hematoma enlargement. Trauma or bleeding tendency may precipitate development of CSH, however, it cannot lead CSH, if there is no sufficient subdural space. The key determinant for development of CSH is a sufficient subdural space, in other words, brain atrophy. The most common and universal cause of brain atrophy is the aging. Modifying Virchow's description, CSH is sometimes traumatic, but most often caused by degeneration of the brain. Now, it is reasonable that degeneration of brain might play pivotal role in development of CSH in the aged persons.

Do Long Term Savings Motives Foster Household Participation and Contribution to Savings Mechanisms in Rural Vietnam?

  • HA, Van Dung
    • The Journal of Asian Finance, Economics and Business
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    • v.6 no.2
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    • pp.75-82
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    • 2019
  • The paper aims to investigate the impacts of long-term savings motives on fostering household participation and contribution to savings mechanisms in rural Vietnam. The paper is organized in five parts: introduction, data description, methodology, empirical results, and conclusion. The quantitative methodology is employed and three simultaneous estimation methods, including instrumental variable model, two-step model, and Heckman model are used to test these impacts as well as the robustness of results. In each model, the paper examines the impacts of independent factors on both household participation and household contribution to savings mechanisms. Two sets of independent variables: long-term savings motives (profit-making investment, accumulation for big expenditure, providing for old age, and cost of educations) and control variables (dependency rate, number of people in household, and household wealth) are in each model. A set of dataset of 2,314 households for analysis is obtained from household survey in rural Vietnam. Robust statistical findings indicate that profit-making investment emerged to be the strongest motive fostering household participation to savings mechanisms while other long-term savings motives have little or no impact on fostering household participation to savings mechanisms. In addition, education investment encourages household contribution to savings mechanisms in rural Vietnam.

Effects of Message Types on the Intention to Purchase Luxury Fashion Products Online (온라인 웹사이트 내에서의 럭셔리 브랜드의 상품 메시지 유형에 따른 구매 의도 연구)

  • Choi, Dayeon;Ko, Eunju
    • Fashion & Textile Research Journal
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    • v.23 no.4
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    • pp.448-457
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    • 2021
  • This study aimed to identify messages that induce positive product attitudes and purchase intentions among luxury consumers in online luxury sales. Message types elicited from luxury products were classified as quantity-limited, time-limited, sustainability, and personalization. A total of 150 participants were recruited through a Google survey, and all respondents were randomly assigned to respond to one of five stimuli (quantity-limited, time-limited, sustainability, personalization, and control). Participants were informed that they would be engaging in luxury online shopping and read a description about it. Results showed that message attitude, product attitude, and purchase intention were positively formed with the quantity-limited and personalization message types. Furthermore, we discovered the underlying mechanism for quantity-limited and personalization messages increasing favorable message attitudes and it affected the product attitude. Finally, it increased the purchase intention of the product. By confirming purchase intentions according to message types for luxury brands, we have expanded the scope of advertising research to include online luxury sales platforms. Since luxury online shopping is inevitable, this study suggests that the effective use of message types such as quantitylimited and personalization would improve online sales.

Mathematical model and sensitivity analysis for describing emulsification in ASP flooding

  • Zhang, Chengli;Wang, Peng;Song, Guoliang
    • Geosystem Engineering
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    • v.21 no.6
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    • pp.335-343
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    • 2018
  • Alkali-surfactant polymer flooding has become an important technique to improve oil recovery following the development of oil fields while the function of emulsification in enhanced oil recovery is rarely considered in the existing mathematical model for numerical simulation. In this paper, the mechanism of improving the recovery of the emulsification was analyzed in ASP flooding, and a relatively perfect mathematical model with deep filtration-theory was established, in which oil-water volume equation, saturation equation, viscosity equation, and permeability reduction equation are included. The new model is used to simulate the actual block of an oil field; the simulated results of the new model and an old model without considering the emulsification are compared with the actual well history. It is found that new model which is easy to be realized in numerical simulation has a high precision fitting, and the effect of adding oil and decreasing water is obvious. The sensitivity of emulsification was analyzed, and the results show that the water reducing funnel becomes wider and the rate of water cut decreases rapidly with the increase of emulsifying capacity, and then the rate of recovery slows down. The effect of increasing oil and decreasing water is better, and the degree of recovery increases. The emulsification of the ASP flooding is maintained at a moderate level, which corresponds to ${\Phi}=0.2$ in the new model, and the emulsification is applied to realize the general mathematical quantitative description, so as to better guide the oilfield development.

Snake Venom Phospholipase A2 and its Natural Inhibitors

  • Singh, Pushpendra;Yasir, Mohammad;Khare, Ruchi;Tripathi, Manish Kumar;Shrivastava, Rahul
    • Natural Product Sciences
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    • v.26 no.4
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    • pp.259-267
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    • 2020
  • Snakebite is a severe medical, economic, and social problem across the world, mostly in the tropical and subtropical area. These regions of the globe have typical of the world's venomous snakes present where access to prompt treatment is limited or not available. Snake venom is a complex mixture of toxin proteins like neurotoxin and cardiotoxin, and other enzymes like phospholipase A2 (PLA2), haemorrhaging, transaminase, hyaluronidase, phosphodiesterase, acetylcholinesterase, cytolytic and necrotic toxins. Snake venom shows a wide range of biological effects like anticoagulation or platelet aggregation, hemolysis, hypotension and edema. Phospholipase A2 is the principal constituent of snake venom; it catalyzes the hydrolysis of the sn-2 position of membrane glycerophospholipids to liberate arachidonic acid, which is the precursor of eicosanoids including prostaglandins and leukotrienes. The information regarding the structure and function of the phospholipase A2 enzyme may help in treating the snakebite victims. This review article constitutes a brief description of the structure, types, mechanism occurrence, and tests of phospholipase A2 and role of components of medicinal plants used to inhibit phospholipase A2.

The pharmacological role of Ginsenoside Rg3 in liver diseases: A review on molecular mechanisms

  • Wenhong Wang;Ke Li;Weihua Xiao
    • Journal of Ginseng Research
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    • v.48 no.2
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    • pp.129-139
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    • 2024
  • Liver diseases are a significant global health burden and are among the most common diseases. Ginssennoside Rg3 (Rg3), which is one of the most abundant ginsenosides, has been found to have significant preventive and therapeutic effects against various types of diseases with minimal side effects. Numerous studies have demonstrated the significant preventive and therapeutic effects of Rg3 on various liver diseases such as viral hepatitis, acute liver injury, nonalcoholic liver diseases (NAFLD), liver fibrosis and hepatocellular carcinoma (HCC). The underlying molecular mechanism behind these effects is attributed to apoptosis, autophagy, antioxidant, anti-inflammatory activities, and the regulation of multiple signaling pathways. This review provides a comprehensive description of the potential molecular mechanisms of Rg3 in the development of liver diseases. The article focuses on the regulation of apoptosis, oxidative stress, autophagy, inflammation, and other related factors. Additionally, the review discusses combination therapy and liver targeting strategy, which can accelerate the translation of Rg3 from bench to bedside. Overall, this article serves as a valuable reference for researchers and clinicians alike.

An Efficient Bitmap Indexing Method for Multimedia Data Reflecting the Characteristics of MPEG-7 Visual Descriptors (MPEG-7 시각 정보 기술자의 특성을 반영한 효율적인 멀티미디어 데이타 비트맵 인덱싱 방법)

  • Jeong Jinguk;Nang Jongho
    • Journal of KIISE:Computer Systems and Theory
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    • v.32 no.1
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    • pp.9-20
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    • 2005
  • Recently, the MPEG-7 standard a multimedia content description standard is wide]y used for content based image/video retrieval systems. However, since the descriptors standardized in MPEG-7 are usually multidimensional and the problem called 'Curse of dimensionality', previously proposed indexing methods(for example, multidimensional indexing methods, dimensionality reduction methods, filtering methods, and so on) could not be used to effectively index the multimedia database represented in MPEG-7. This paper proposes an efficient multimedia data indexing mechanism reflecting the characteristics of MPEG-7 visual descriptors. In the proposed indexing mechanism, the descriptor is transformed into a histogram of some attributes. By representing the value of each bin as a binary number, the histogram itself that is a visual descriptor for the object in multimedia database could be represented as a bit string. Bit strings for all objects in multimedia database are collected to form an index file, bitmap index, in the proposed indexing mechanism. By XORing them with the descriptors for query object, the candidate solutions for similarity search could be computed easily and they are checked again with query object to precisely compute the similarity with exact metric such as Ll-norm. These indexing and searching mechanisms are efficient because the filtering process is performed by simple bit-operation and it reduces the search space dramatically. Upon experimental results with more than 100,000 real images, the proposed indexing and searching mechanisms are about IS times faster than the sequential searching with more than 90% accuracy.

A Design-phase Quality Model for Ubiquitous Service Ontology (유비쿼터스 서비스 온톨로지를 위한 설계 품질 모델)

  • Lee, Mee-Yeon;Park, Seung-Soo;Lee, Jung-Won
    • Journal of KIISE:Software and Applications
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    • v.37 no.6
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    • pp.430-445
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    • 2010
  • Effective service description and modeling methodologies are essential for dynamic service composition to provide autonomous services for users in ubiquitous computing environments. In our previous research, we proposed a 'u-Service' as an abstract and structured concept for operations of devices in ubiquitous environments. In addition, we established the mechanism to structure u-Services as an ontology and the description specification to represent attributes of u-Services. However, it did not provide enough methods or standards to analyze and evaluate the effectiveness of the u-Service ontology in the design time. Since existing quality models for software products or computing systems cannot consider characteristics of ubiquitous services, they are not suitable for ubiquitous service ontology. Therefore, in this paper, we propose a quality evaluation model to design and modeling a good ubiquitous service ontology, based on our u-Service ontology building process. We extract modeling goals and evaluation indicators according to characteristics of ubiquitous service ontology, and establish quality metrics to quantify each quality sub-characteristics. The experiment result of the proposed quality evaluation model for u-Service ontologies which are constructed for our previous works shows that we can analyze the design of ubiquitous service ontology from various angles, and indicate recommendations for improvement.

Recent Studies of Breast Cancer in Traditional Chinese Medicine Journals (중의학 논문에 나타난 유방암의 연구 동향에 대한 고찰 - 중의학 논문을 중심으로 -)

  • Jerng, Ui-Min;Jeong, Jong-Soo;Park, Jae-Woo;Jung, Hyun-Sik;Yoon, Seong-Woo
    • The Journal of Korean Obstetrics and Gynecology
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    • v.22 no.1
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    • pp.263-278
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    • 2009
  • Purpose: The purpose of this study is to research trends in the study of breast cancer in Traditional Chinese Medicine (TCM) and to establish the further direction for its study. Methods: We reviewed TCM papers published in the last 29 years (1979-2008). Results: 1. We researched 49 papers and the patterns of study were as follows: in vitro studies were 27 papers (55.1%), in vivo studies were 9 papers (18.4%) and clinical studies were 19 papers (38.8%). 2. In vitro studies on breast cancer research in TCM were focused on cytotoxicity (17 papers) and apoptosis (8 papers). Most of in vivo studies (6 papers) were done for the purpose of inducing growth suppression of tumor cell after administration of the test drug. Each drug acted on this effect through various types of mechanism. 3. Unlike in vitro and in vivo studies, clinical studies on growth suppression of tumor cell were rare (4 papers). Most of the studies were focused on reduction of side effect of chemotherapy or synergistic effect with chemotherapy (7 papers), immune regulation (7 papers), and improvement of quality of life (6 papers). 4. Among the treatment method we reviewed, 'Runing Ⅱ(Ⅱ號方)' was the only medication that further studied as clinical trial after experimental study. 5. Since almost all studies have defects like poorly designed model or insufficient data description, it was difficult to make any definite conclusion about these studies. Conclusion: More subsequent clinical studies based on experimental study will be needed afterwards. Strict and high-level study design with detailed description will be needed in further study.

Efficient Image Retrieval using Minimal Spatial Relationships (최소 공간관계를 이용한 효율적인 이미지 검색)

  • Lee, Soo-Cheol;Hwang, Een-Jun;Byeon, Kwang-Jun
    • Journal of KIISE:Databases
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    • v.32 no.4
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    • pp.383-393
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    • 2005
  • Retrieval of images from image databases by spatial relationship can be effectively performed through visual interface systems. In these systems, the representation of image with 2D strings, which are derived from symbolic projections, provides an efficient and natural way to construct image index and is also an ideal representation for the visual query. With this approach, retrieval is reduced to matching two symbolic strings. However, using 2D-string representations, spatial relationships between the objects in the image might not be exactly specified. Ambiguities arise for the retrieval of images of 3D scenes. In order to remove ambiguous description of object spatial relationships, in this paper, images are referred by considering spatial relationships using the spatial location algebra for the 3D image scene. Also, we remove the repetitive spatial relationships using the several reduction rules. A reduction mechanism using these rules can be used in query processing systems that retrieve images by content. This could give better precision and flexibility in image retrieval.