• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.7
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• pp.53-61
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• 2008

Consider a typical wireless sensor network in which stem nodes form the backbone network of mesh topology while each stem node together with leaf nodes in its vicinity forms a subnetwork of star topology. In such a wireless sensor network, we must heed the following when we design a MAC scheme supporting the packet delivery from a leaf node to a stem node. First, leaf nodes are usually battery-powered and it is difficult to change or recharge their batteries. Secondly, a wireless sensor network is often deployed to collect and update data periodically. Late delivery of a data segment by a sensor node causes the sink node to defer data processing and the data segment itself to be obsolete. Thirdly, extensive signaling is extremely limited and complex computation is hardly supported. Taking account of these facts, a MAC scheme must be able to save energy and support timeliness in packet delivery while being simple and robust as well. In this paper, we propose a version of ALOHA as a MAC scheme for a wireless sensor network. While conserving the simplicity and robustness of the original version of ALOHA, the proposed version of ALOHA possesses a distinctive feature that a sensor node decides between stop and continuation prior to each delivery attempt for a packet. Such a decision needs a stopping rule and we suggest a Bayes stopping rule. Note that a Bayes stopping rule minimizes the Bayes risk which reflects the energy, timeliness and throughput losses. Also, a Bayes stopping rule is practical since a sensor node makes a decision only using its own history of delivery attempt results and the prior information about the failure in delivery attempt. Numerical examples confirm that the proposed version of ALOHA employing a Bayes stopping rule is a useful MAC scheme in the severe environment of wireless sensor network.

• Korean Journal of Plant Resources
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• v.7 no.1
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• pp.63-66
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• 1994

The experiment was carried out to study the bothanical characteristics of Aconitum charmichaeli Sieb. et Zucc in Korea.The results obtained are summarized as follows ; maximum flowering date was 15 Sep. and plantheight was 65cm, stem diameter was 8.7mm, No. of node was 25 and node of flowering initiation was15th.In flowering, No. of anothers were 52 and No. of flowers were 49.In leaf, length and width was same size, lower leaf size was 2-3 times than upper leaf, lower leafarea was 8.4 times than upper leaf.In tuber, No. of tuber per plant was 8, fresh weight per tuber was 25.4g, total fresh weight per plantwas about 200g.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2000.10b
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• pp.53-59
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• 2000

This study was carried out to determine the effect of sowing time on the flowering, growth and yield of Schizonepeta tenutfozia Briquet. Emergence and flowering dates in the sowing time from March 30 to April 30 were earlier than those of the other sowing times. In the sowing time from March 30 to April 30, length and diameter of main stem, number of node per main stem, number of branch per plant and fresh and dry weight of stem were greater than those of the other sowing times. Yield components such as ear length, main stem length and diameter, branches per plant, number of node and ears per plant, yield of stem in fresh and dry were the highest at the sowing time from March 30 to April 30. Optimum sowing time of Schizonepeta tenuifolia Briquet were from March 30 to April 30 in southern areas of Korea.

• Journal of Plant Biology
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• v.36 no.1
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• pp.29-34
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• 1993

Observation was made on early ontogeny of vascular cambium in the cotyledonary node of Pinus koraiensis seedling in order to clarify the cambial ontogeny of the node which was hardly elongated. In transverse view, the derivatives by the early periclinal divisions at the outer region of the procambial strands differentiated to protophloem with establishing a certain degree of radial seriations. Later, some cells in the central region of the procambial strands begin divide periclinally, eventually the cells, differentiate gradually to the vascular cambium. In tangential view, early procambium is consisted of homogeneous short cells with transverse end walls which are tansformed into the long cells and short cells gradually. The long cells continue intrusive growth and the short cells repeat transverse division. Finally, the long and short cells differentiated to cambial fusiform initials and ray initials respectively. In tangential section, the differentiation pattern of cambial initials resembles that of the stem of Ginkgo biloba. But in transverse view, the characteristics in the origin of vascular cambium of the cotyledonary node resembles that of root. The vascular cambium in cotyledonary node is completed after eleven prophylls were formed.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7491-7496
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• 2015

Background: Biomarkers in breast neoplasms provide invaluable information regarding prognosis and help determining the optimal treatment. We investigated the possible correlation between cancer stem cell (CSC) markers (CD133, and ALDH1) in invasive ductal breast carcinomas with some clinicopathological parameters. Aim: To assess the correlation between expression of cancer stem cell (CSC) markers (CD133, and ALDH1) and clinicopathological parameters of invasive ductal breast carcinomas. Materials and Methods: Immunohistochemical analysis of CD133 and ALDH1 was performed on a series of 120 modified radical mastectomy (MRM) specimens diagnosed as invasive ductal breast carcinoma. Results: Expression of both CD133 and ALDH1 was significantly changed and related to tumor size, tumor stage (TNM), and lymph node metastasis. A negative correlation between CD133 and ALDH1 was found. Conclusions: Detecting the expression of CD133 and ALDH1 in invasive ductal breast carcinomas may be of help in more accurately predicting the aggressive properties and determining the optimal treatment.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.245-248
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• 1997

Excessive stress on the bone-stem interface may cause local micromotion that could produce midthigh pain, interface bone resorption and prevent bony ingrowth. It is important for clinician and prosthetic designer to develop an understanding of the load transfer mechanism, its associated stress pattern and its relationships with the particular mechanical characteristics of the femoral stem designs. Finite element method (FEM) is preeminently suited to provide information in this respect. The authors developed 3-dimensional numerical finite element models implanted with the straight stem which is composed of total 1170 elements of 8 nodes and with the curved stem which is composed of total 885 elements of 8 node, and analysed the relative micromotions between the straight stem and the curved stem in immediate postoperative stage of an uncemented total hip replacement in load simulating the single leg stance. The results showed that the rotational displacement was occupied over 90% of total micromotion in both types of stem and was peak at the proximal medial portion of the stem, but markedly less distally. The curved stem was more stable especially in terms of rotational stability. It is recommended that surgeons do not allow the patient weight bearing until bony ingrowth was achieved. In the future more attention should be drawn to increase initial rotational stability of the two types of femoral stem to prevent loosening from excessive micromotion.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.4
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• pp.364-369
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• 1989

Leaf characteristics of main stem and tiller of IK type maize (IK/ /IRI/B68) were compared with those of Jinjoo Ok hybrid which are not usually tillered. A total of nine leaves from flag leaf to the third or the fourth leaf below ear-bearing node were sampled from each stem or tiller. There was no significant difference in mean leaf length between IK/ /IRI/B68 and Jinjoo Ok. But the mean leaf width of IK/ /IRI/ B68 was about 2 cm narrower than that of Jinjoo Ok. The mean leaf area of the IK/ /IRI/B68 was also smaller than that of Jinjoo Ok due to the narrower leaf width. There were not significant differences in mean leaf characteristics between main stem and tillers of IK/IRI/B68. The longest leaf was the leaf below the ear-bearing node and the widest leaf was the leaf just above the ear-bearing node. Mean length. width and area of leaf on main stem and tillers were similar. Coefficients of variation calculated for individual leaf indicated that the leaves near the ear-bearing node were more uniform than others. The leaf area measured was significantly greater than that estimated by formular, length x width x 0.75. New constant to estimate leaf area of tillering maize was derived as 0.8.

• International Journal of Stem Cells
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• v.15 no.3
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• pp.247-257
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• 2022

Background and Objectives: Although human-induced pluripotent stem cells (hiPSC) can be efficiently differentiated into cardiomyocytes (CMs), the heterogeneity of the hiPSC-CMs hampers their applications in research and regenerative medicine. Retinoic acid (RA)-mediated signaling pathway has been proved indispensable in cardiac development and differentiation of hiPSC toward atrial CMs. This study was aimed to test whether RA signaling pathway can be manipulated to direct the differentiation into sinoatrial node (SAN) CMs. Methods and Results: Using the well-characterized GiWi protocol that cardiomyocytes are generated from hiPSC via temporal modulation of Wnt signaling pathway by small molecules, RA signaling pathway was manipulated during the differentiation of hiPSC-CMs on day 5 post-differentiation, a crucial time point equivalent to the transition from cardiac mesoderm to cardiac progenitor cells in cardiac development. The resultant CMs were characterized at mRNA, protein and electrophysiology levels by a combination of qPCR, immunofluorescence, flow cytometry, and whole-cell patch clamp. The results showed that activation of the RA signaling pathway biased the differentiation of atrial CMs, whereas inhibition of the signaling pathway biased the differentiation of sinoatrial node-like cells (SANLCs). Conclusions: Our study not only provides a novel and simple strategy to enrich SANLCs but also improves our understanding of the importance of RA signaling in the differentiation of hiPSC-CMs.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.2
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• pp.194-200
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• 2014

This study investigated the chemical composition and ruminal degradability of corn stover in three maize-planting regions in Qiqihaer, Heilongjiang Province, China. The whole stover was separated into seven morphological fractions, i.e., leaf blade, leaf sheath, stem rind, stem pith, stem node, ear husk, and corn tassel. The assessment of nutritive value of corn stover and its fractions was performed based on laboratory assays of the morphological proportions, chemical composition, and in situ degradability of dry matter (DM), neutral detergent fiber (NDF), and acid detergent fiber (ADF). The chemical composition of corn stover was significantly different from plant top to bottom (p<0.05). Among the whole corn stover and seven morphological fractions, leaf blade had the highest crude protein (CP) content and the lowest NDF and ADF contents (p<0.05), whereas stem rind had the lowest CP content and the highest ADF and acid detergent lignin (ADL) contents (p<0.05). Ear husk had significantly higher NDF content and relatively lower ADL content than other corn stover fractions. Overall, the effective degradability of DM, NDF, and ADF in rumen was the highest in leaf blade and stem pith, followed by ear husk. The results indicate that leaf blade, ear husk, and stem pith potentially have higher nutritive values than the other fractions of corn stover. This study provides reference data for high-efficiency use of corn stover in feeding ruminants.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.741-743
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• 1998

A bacterial disease of pepper (Capsicum annuum L.) that rooted the stem nodes to black was found in pepper plants which cultivated in plastic house at Chungdo, Kyungpook, Korea in March, 1998. Bacterial isolates derived from the diseased peppers were pathogenic to potato, eggplant and Chinese cabbage but, was not pathogenic to chrysanthemum by artificial inoculation. On the basis of bacteriological characteristics and pathogenicity test on host plants, the causal organism of the node soft rot of pepper is identified as Erwinia carotovora subsp. carotovora and the name of disease is proposed as bacterial node soft rot of pepper.