• Title/Summary/Keyword: (n, k) -way System

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Quantification of the tug-back by measuring the pulling force and micro computed tomographic evaluation

  • Jeon, Su-Jin;Moon, Young-Mi;Seo, Min-Seock
    • Restorative Dentistry and Endodontics
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    • v.42 no.4
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    • pp.273-281
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    • 2017
  • Objectives: The aims of this study were to quantify tug-back by measuring the pulling force and investigate the correlation of clinical tug-back pulling force with in vitro gutta-percha (GP) cone adaptation score using micro-computed tomography (${\mu}CT$). Materials and Methods: Twenty-eight roots from human single-rooted teeth were divided into 2 groups. In the ProTaper Next (PTN) group, root canals were prepared with PTN, and in the ProFile (PF) group, root canals were prepared using PF (n = 14). The degree of tug-back was scored after selecting taper-matched GP cones. A novel method using a spring balance was designed to quantify the tug-back by measuring the pulling force. The correlation between tug-back scores, pulling force, and percentage of the gutta-percha occupied area (pGPOA) within apical 3 mm was investigated using ${\mu}CT$. The data were analyzed using Pearson's correlation analysis, one-way analysis of variance (ANOVA) and Tukey's test. Results: Specimens with a strong tug-back had a mean pulling force of 1.24 N (range, 0.15-1.70 N). This study showed a positive correlation between tug-back score, pulling force, and pGPOA. However, there was no significant difference in these factors between the PTN and PF groups. Regardless of the groups, pGPOA and pulling force were significantly higher in the specimens with a higher tug-back score (p < 0.05). Conclusions: The degree of subjective tug-back was a definitive determinant for master cone adaptation in the root canal. The use of the tug-back scoring system and pulling force allows the interpretation of subjective tug-back in a more objective and quantitative manner.

The Relaxant Effect of Propofol on Isolated Rat Intrapulmonary Arteries

  • Zhang, Guangyan;Cui, Jianxiu;Chen, Yijing;Ma, Jue
    • The Korean Journal of Physiology and Pharmacology
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    • v.18 no.5
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    • pp.377-381
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    • 2014
  • Propofol is a widely used anesthetic. Many studies have shown that propofol has direct effects on blood vessels, but the precise mechanism is not fully understood. Secondary intrapulmonary artery rings from male rats were prepared and mounted in a Multi Myograph System. The following constrictors were used to induce contractions in isolated artery rings: high $K^+$ solution (60 mmol/L); U46619 solution (100 nmol/L); 5-hydroxytryptamine (5-HT; $3{\mu}mol/L$); or phenylephrine (Phe; $1{\mu}mol/L$). The relaxation effects of propofol were tested on high $K^+$ or U46619 precontracted rings. Propofol also was added to induce relaxation of rings preconstricted by U46619 after pretreatment with the nitric oxide synthase inhibitor $N^G$-nitro-L-arginine methyl ester (L-NAME). The effects of propofol on $Ca^{2+}$ influx via the L-type $Ca^{2+}$ channels were evaluated by examining contraction-dependent responses to $CaCl_2$ in the absence or presence of propofol (10 to $300{\mu}mol/L$). High $K^+$ solution and U46619 induced remarkable contractions of the rings, whereas contractions induced by 5-HT and Phe were weak. Propofol induced dose-dependent relaxation of artery rings precontracted by the high $K^+$ solution. Propofol also induced relaxation of rings precontracted by U46619 in an endothelium-independent way. Propofol at different concentrations significantly inhibited the $Ca^{2+}$-induced contractions of pulmonary rings exposed to high $K^+$-containing and $Ca^{2+}$-free solution in a dose-dependent manner. Propofol relaxed vessels precontracted by the high $K^+$ solution and U46619 in an endothelium-independent way. The mechanism for this effect may involve inhibition of calcium influx through voltage-operated calcium channels (VOCCs) and receptor-operated calcium channels (ROCCs).

Removal Behavior of Biological Nitrogen and Phosphorus and Prediction of Microbial Community Composition with Its Function, in an Anaerobic-Anoxic System form Weak Sewage

  • LEE, JIN WOO;EUI SO CHOI;KYUNG IK GIL;HAN WOONG LEE;SANG HYON LEE;SOO YOOUN LEE;YONG KEUN PARK
    • Journal of Microbiology and Biotechnology
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    • v.11 no.6
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    • pp.994-1001
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    • 2001
  • An easier way of understanding the BNR system was proposed from the study on substrate, nutrient removal tendency, microbial community and its metabolic function by applying the municipal settled sewage. During the anaerobic period, the phosphorus release rate per VFACOD we varied depending on the phosphorus content in the sludge. When the phosphorus content in the sludge was $6\%$ VSS, according to influent VFACOD, the phosphorus release rate and PHA production were $0.35 gPO_4P/gVFACOD$ and 1.0 gPHA/gVFACOD, respectively. The $NO_3N$ requirement for the phosphorus uptake as an electron acceptor was about $0.5 gNO_3N/gPO_4P_{uptake}$ based on the proposed equation with PHA, biomass, production, and the concentration of phosphorus release/uptake. Bacterial-community analysis of the sludge, as determined by FISH and 16SrDNA characterization FISH, revealed that the beta-subclass proteobacteria were the most abundant group ($27.9\%$ of the proteobacteria-specific probe EUB338), and it was likely that representative of the beta-subclass played key roles in activated sludge. The next dominant group found was the gamma-protebacteria ($15.4\%$ of probe EUB338). 16S rDNA clone library analysis showed that the members of${\beta}$- and ${\gamma}$-proteobacteria were also the most abundant groups, and $21.5\%$ (PN2 and PN4) and $15.4\%$ (PN1 and PN5) of total clones were the genera of denitrifying bacteria and PAO, respectively. Prediction of the microbial community composition was made with phosphorus content (Pv, $\%$ P/VSS) in wasted sludge and profiles of COD, PHA, $PO_4P,\;and\;NO_3N$ in an anaerobic-anoxic SBR unit. Generally, the predicted microbial composition based upon metabolic function, i.e., as measured by stoichiometry, is fairly similar to that measure by the unculturable dependent method. In this study, a proposal was made on he microbial community composition that was more easily approached to analyze the reactor behavior.

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USN Secure Communication Design Using Chaotic System Feedback Synchronization (혼돈계의 피드백 동기화를 이용한 USN 보안통신 설계)

  • Yim, Geo-Su
    • The Journal of the Korea institute of electronic communication sciences
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    • v.13 no.5
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    • pp.1011-1016
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    • 2018
  • Ubiquitous services for the convenience and safety of human beings along with the development of society are being realized through RFID technology and sensor network, and its application range of fields is also broaden. However, since the USN contains all the information of individuals and things, all of its private spaces can be attacked by external attacks; so, that the problem of security continues to arise. We designed a one-way chaotic feedback synchronization method as a secure communication method to fit the USN composed of one sync node and n number of sensor nodes. We designed the method by which the sensor node is synchronized in one direction of the sync node. This method solves the problem that all sensor nodes need to be resynchronized when the sync node is changed, which is shown in bidirectional synchronization. This is a security method that can be effectively applied to 1:n communication such as USN.

A Study on the Knowledge-Based T.P.N. System (1) (지식 구조화 경정맥 완전 영양공급 시스템의 개발에 관한 연구 (I))

  • Jeon, Gye-Rok;Choe, Sam-Gil;Byeon, Geon-Sik
    • Journal of Biomedical Engineering Research
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    • v.11 no.2
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    • pp.305-314
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    • 1990
  • In this paper we have implemented and tested TPN which is system to supply sufficent nutrition to nutritionally deficient patient by means of ES (expert system) a kind of A.1 (artificial intelligence) . This system affords to evaluation of nutritional state of patient which is essential to physi- cian. who performs TPN, decision of performing TPN and management of patient-data & calculation of information needing to making TPN fluid. The features were as follolv 1. we input data, take ideal weight of patient and 24hr's creatlnln In urine according to chart in system compare TSF (triceps skin fold), MAC (mid-arm circumference), AMC (arm muscle circumference) to 5th, 15th, 50th percentile and evaluate the nutritional state of patient. 2. Calculation of protein & nonprotein calorie needing to treament of patient can be made exactly by stress factor, activity factor and body temperature. 3. patient's personal recording needing to management of patient date name of chief doc- tor, name of department of admission, chart number, history can by taken very easily. 4. The way of system operating is pull-down Menu one, It can be processing very efficiently. 5. Date processing in system, we can manage memory volume of computer verlr efficiently using of dynamic allocation variables. 6. We can make it very easy to edit & revise the input data, processed data is saved to diskette in 2 files (TDF, THF) , these are semipermanent preservation.

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Quantified Analyses of Musk Deer Farming in China: A Tool for Sustainable Musk Production and Ex situ Conservation

  • Meng, Xiuxiang;Gong, Baocao;Ma, Guang;Xiang, Leilei
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.10
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    • pp.1473-1482
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    • 2011
  • Adult male musk deer (Moschus spp.) secrete musk, a widely used ingredient in traditional Asian medicine and the international perfume industry. Musk deer are endangered due to historic over-utilization of musk and habitat loss. Musk deer farming, provides an important way of conserving musk deer and ensuring a sustainable musk supply. For over 50 years musk deer farming has been conducted in China with the endangered Alpine musk deer (Moschus sifanicus) the predominant farmed musk deer species. To date, few studies have examined the musk production of captive musk deer. This study analyzed musk-extraction data collected from 1997 to 2009 at Xinglongshan Musk Deer Farm, Gansu, China. The musk-extraction ratio (MER) of captive male musk deer was 90.30% (n = 732), while the annual average musk extraction (AME) per animal was $7.90{\pm}0.17\;g$ with the range from 0.00 g to 34.20 g (n = 732). The origin of the deer had an influence on AME and MER production, with male wild-captured (WC) individuals recording higher values (AME, $8.76{\pm}0.27\;g$, n = 272; MER, 93.75%, n = 272) than those of captive breeding (CB) males (AME: $7.39{\pm}0.22\;g$, n = 460; MER: 88.26%, n = 460). The origin of an individual's parents, however, did not influence AME and MER. Age also influenced musk production with the MER of 1.5-year-old males being 87.5% with an average musk production of $8.27{\pm}0.47\;g$ (n = 96). The peak period for musk production was from 1.5 to 8.5 years of age. The results of our study demonstrate musk deer farming could work as an effective measure to protect musk deer and provide sustainable musk resources, however, the musk production including MER and AME could be improved through optimizing the managing and breeding system in endangered musk deer farming.

The Effect of Thoracic Joint Mobilization on Pain, Proprioception and Static Balance in Patients With Chronic Low Back Pain (흉추 관절가동술이 만성요통환자의 통증, 고유수용감각 및 균형수준에 미치는 효과)

  • Yang, Jin-mo;Kim, Suhn-yeop
    • Physical Therapy Korea
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    • v.22 no.3
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    • pp.1-11
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    • 2015
  • The purpose of this study was to investigate the effect of lumbar stabilization training and additional thoracic mobilization on pain, proprioception and static balance in patients with chronic low back pain. The subjects of this study were 48 chronic low back pain patients who were randomly allocated to an experimental group 1 ($n_1=16$, lumbar stabilization and thoracic mobilization, thoracic hypomobility), experimental group 2 ($n_2=16$, lumbar stabilization and thoracic mobilization, thoracic normal mobility), and a control group ($n_3=16$, lumbar stabilization, thoracic hypomobility) after a thoracic mobility test. Both experimental groups underwent lumbar stabilization training and additional thoracic mobilization. The control group underwent only lumbar stabilization training. The intervention was performed 3 times per week, 30 minutes each time, for a total of 6 weeks. Thoraco-lumbar joint reposition error was measured using an electrogoniometer and static balance ability was measured using the Tetrax posture analysis system. Subjects' pain level was measured using a 100 mm visual analogue scale. Statistical analyses were performed using a one-way analysis of variance and a paired t-test. Post-hoc testing was carried out with a Bonferroni test. The pain level was significantly lower in both experimental groups compared to the control group. Both experimental groups showed significant reductions in joint reposition error angle (flexion, extension, and side bending) compared to the control group. The static balance level was significantly lower in both experimental groups than in the control group. In summary, lumbar stabilization exercises and additional thoracic mobilization significantly improved the pain level, proprioception, and static balance in patients with chronic low back pain.

Comparison of Decision System in both Differentiation of Syndromes and Treatments(辨證論治) and Divination by Achillea sibirica(蓍草占) (변증논치(辨證論治)와 시초점(蓍草占)의 의사결정(意思決定) 체계(體系) 비교)

  • Jo, Hak-Jun
    • Journal of Korean Medical classics
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    • v.25 no.4
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    • pp.39-55
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    • 2012
  • Objective : In order to find the decision system in differentiation of syndromes and treatments, I paid attention to divination by Achillea sibireca. Method : I pulled out the elements of differentiation of syndromes and treatments in Zh$\bar{o}$ng y$\bar{i}$n$\grave{e}$i k$\bar{e}$ xu$\acute{e}$(中醫內科學), Uihagipmun Sanghan(醫學入門 傷寒), Donguibogam Japbyeong(東醫寶鑑 雜病) and compared them with the horoscope in The Book of Changes(周易) from the relativity of both eight principles(八綱) etc and subdivision in the entity of the cosmos (太極內 分化). Result : From this viewpoint, the decision system that has relative references in differentiation of syndromes & treatments on cold diseases(傷寒病) and complexed diseases(雜病) by eight principles etc can be compared with the decision system in divination by Achillea sibireca that the entity of the cosmos(太極) gradually can be breakdown into the positive and negative(陰陽), the positive and negative can be breakdown into four phases(四象), four phases can be breakdown into eight signs of divination(八卦), eight signs of divination can be breakdown into 64 divination signs(64卦). Conclusion : I had found that differentiation of syndromes and treatments and divination by Achillea sibireca have similarity to each other in side of decision system. Those decision systems for clinical use and telling the future has many relative references and are made of multiple structures. Clinician can easily, exactly distinguish similar syndromes of many another diseases through this way.

INFLUENCE OF APPLICATION METHODS OF A DENTIN ADHESIVE ON SHEAR BOND STRENGTH AND ADHESIVE PATTERN (상이질 접착제의 적용방법에 따른 전단결합강도와 접착양상에 관한 연구)

  • Park, Sung-Taek;Moon, Joo-Hoon;Cho, Young-Gon;Ohn, Yeong-Suck
    • Restorative Dentistry and Endodontics
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    • v.24 no.2
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    • pp.381-391
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    • 1999
  • A new 5th generation adhesive system(ONE-STEP) has been supplied which operators can apply to conditioned tooth surfaces by one simplified step. The purpose of this study was to determine whether different methods of adhesive application and various air drying duration after applying adhesive affect the shear bond strength of composite resin to dentin, and to evaluate the adhesive pattern of composite resin and dentin under SEM. Seventy-seven extracted human molar teeth were cleaned and mounted in palstic test tubes. The occlusal dentin surfaces were exposed with Diamond Wheel Saw and smoothed with Lapping and Polishing Machine (South Bay Technology Co., U.S.A.). Teeth were randomly divided into 7 groups (n=11), In experimental A group, adhesive was applied to dentin with agitation for 20 sec. In experimental N-A group, adhesive were continuously applied to dentin for 20 sec. Also control and experimental 1, 2, 3, 4 groups were dried for 10, 0, 5, 20, 30 seconds after applying adhesive, respectively, Adhesives were light cured for 10 sec. A gelatin capsule 5mm in diameter was filled with Aelitefil$^{TM}$ composite resin, placed on the treated dentin surface and light cured for 40 see, from three sides, All specimens were stored in distilled water at room temperature for 24 hours. The shear bond strengths were measured using a universal testing machine(AGS-1000 4D, Japan) at a crosshead speed of 5mm/min. An one-way ANOVA and LSD test were used for statistical analysis of the data. For SEM evaluation, seven specimens were made and sectioned. Representive postfracture and seven specimens were mounted on brass stubs, sputter-coated with gold and observed under SEM. The results were as follows : 1. The shear bond strength of experimental A group which adhesive were applied to dentin with agitation was higher than that of experimental N-A group (continuous application), and there was significant difference between two groups (p<0.01). 2. The interface between composite and dentin according to different application methods showed close adaptation in experimental A group and showed tinny gap in experimental N-A group. 3. The shear bond strength accoding to various air drying duration was the lowest value(7.57${\pm}$2.60 MPa) in experimental 1 group, so there was significant difference between experimental 1 group and other four groups (p<0.05). But there was no significant difference of shear bond strength between four groups (p>0.05). 4. The interface between composite and dentin according to various air drying duration showed close adaptation in control group and tinny gap in experimental 3 and 4 groups. But experimental 1 and 2 groups showed $30{\mu}$ and 6 - $10{\mu}m$ thick gaps, respectively.

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Solid Phase Synthesis of N-(3-hydroxysulfonyl)-L-homoserine Lactone Derivatives and their Inhibitory Effects on Quorum Sensing Regulation in Vibrio harveyi (고체상 합성법에 의해 합성된 N-(3-hydroxysulfonyl)-L-homoserine Lactone 유사체들의 Vibrio harveyi 쿼럼 센싱에 대한 저해 효과)

  • Kim, Cheol-Jin;Park, Hyung-Yeon;Kim, Jae-Eun;Park, Hee-Jin;Lee, Bon-Su;Choi, Yu-Sang;Lee, Joon-Hee;Yoon, Je-Yong
    • Microbiology and Biotechnology Letters
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    • v.37 no.3
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    • pp.248-257
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    • 2009
  • The inhibitors against Vibrio harveyi quorum sensing (QS) signaling were developed by modifying the molecular structure of the major signal, N-3-hydroxybutanoyl-L-homoserine lactone (3-OH-$C_4$-HSL). A series of structural derivatives, N-(3-hydroxysulfonyl)-L-homoserine lactones (HSHLs) were synthesized by the solid-phase organic synthesis method. The in vivo QS inhibition by these compounds was measured by a bioassay system using the V. harveyi bioluminescence, and all showed significant inhibitory effects. To analyze the interaction between these compounds and LuxN, a 3-OH-$C_4$-HSL receptor protein of V. harveyi, we tentatively determined the putative signal binding domain of LuxN based on the sequence homology with other acyl-HSL binding proteins, and predicted the partial 3-D structure of the putative signal binding domain of LuxN by using ORCHESTRA program, and further estimated the binding poses and energies (docking scores) of 3-OH-$C_4$-HSL and HSHLs within the domain. In comparison of the result from this modeling study with that of in vivo bioassay, we suggest that the in silica interpretation of the interaction between ligands and their receptor proteins can be a valuable way to develop better competitive inhibitors, especially in the case that the structural information of the protein is limited.