• Journal of the Korean Mathematical Society
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• v.44 no.3
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• pp.511-523
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• 2007

We consider a two parametric family of the planar systems with the form $\dot{x}=P(x,\;y)+{\in}_1p_1(x,\;y)+{\in}_2p_2(x,\;y)$, $\dot{y}=Q(x,\;y)+{\in}_1p_1(x,\;y)+{\in}_2p_2(x,\;y)$, where the unperturbed equation(${\in}_1={\in}_2=0$) is assumed to have at least one periodic solution or limit cycle. Our aim here is to study the behavior of the system under two parametric perturbations; in fact, using the Poincare-Andronov technique, we impose conditions on the system which guarantee persistence of the periodic trajectories. At the end, we apply the result on the Van der Pol equation ; where, we consider the effect of nonlinear damping on the equation. Also the Hopf bifurcation for the Van der Pol equation will be investigated.

• Nuclear Engineering and Technology
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• v.38 no.2
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• pp.129-138
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• 2006

The Gas-cooled Fast Reactor (GFR) is one of the six reactor concepts selected within the framework of the Generation IV initiative and is the reference concept for the Commissariat $\grave{a}$ l'Energie Atomique $(CEA^1)$. Two reactor unit sizes have been considered: 600 MWth and 2400 MWth. As far as thermal-hydraulics is concerned, reactor decay heat removal (DHR) proves to be a major issue. The CEA has conducted exploratory design studies to address this issue and a reference solution for the 600MWth reactor has been recommended.

• Journal of the Korean Chemical Society
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• v.13 no.1
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• pp.41-44
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• 1969

Eine neuentwickelte Methode zur Herstellung von Me${\ss}$praparaten wird fur die Bestmmung der Spurenelemente in Wasser Rontgenfluroreszspektrometrie angewendet. Supuren von Kupfer, Blei, Zink, Nickel, Kobalt und Eisen werden aus großen Mengen von naturlichem Wasser durch Verdampfen konzentriert. Aus der konzentrierten Losung werden die Spurenelemente durch Einleitung von Schwefelwasserstoff bei pH 8 unter Zusatz von Aluminiumsulfat-Trager ausgefallt. Die Niederschlage der Metallsulfide werden durch Membranfilter filtriert, mit Gelatine fixiert und ihre Absolutmengen durch Rontgenfloreszenzanalyze bestimmt. Kupfer, Blei, Zink, Nickel, Kobalt und Eisen werden bei einer Konzentration von 2.5 bis 50.0 p.p.b. mit einer relativen Standardabweichung 14.0% gemesser.

• Clinical and Experimental Pediatrics
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• v.45 no.7
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• pp.917-922
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• 2002

An unbalanced translocation is frequently the result of inheritance of an unbalanced haploid set from a parent with a balanced translocation. Families in which one parent is a balanced translocation carrier fall into the following classes : Those in which none of the possible abnormal offsprings is viable; Those in which one type of offspring, usually the one with the smaller deletion, is born alive; Those in which two types of abnormal offspring are viable. We report a neonate whose karyotype was 46,XX,der(2)t(2;7)(q21;p21.2),der(20)t(2;20)(q21;p13). She was small for her gestational age and had multiple anomalies such as exophthalmos, corneal opacity, short neck, tongue tie, clinodactyly, atrial septal defect, patent ductus arteriosus and ventriculomegaly. Moreover, her mother's karyotype was 46,XX,der(2)t(2;7)(q21;p21.2),del(16)(q22.1),der(20)t(2;20)(q21;p13) but her father had normal karyotype. The same derivative chrosomes were found between mother and her infant, except for del(16)(q22.1) in her mother and these same unbalanced translocations in a two-generation family are extremely rare.

• Biomedical Science Letters
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• v.15 no.1
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• pp.93-96
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• 2009

House dust mites (HDMs) play an important role in the occurrence of allergic diseases such as asthma and atopic dermatitis. Dermatophagoides pteronyssinus (Der p) is one of the most prevalent HDMs. It mediates the activation of T cells and monocytes, and induces the elevation of immunoglobulin E levels in allergic diseases. However, the effects of Der p on human monocytes have not been fully understood. In the present study, we investigated whether or not Der p has a great effect on the chemotactic activity of the human monocytic cell line, THP-1 cells, as induced by CC chemokines. We also show that the Der p extract (DpE) increased the chemotactic activity of THP-1 cells in response to MCP-1, RANTES, MIP-1${\alpha}$, and TARC, but had no effect on the expressions of CC chemokine receptors (CCRs) binding to CC chemokines in THP-1 cells. Protease inhibitors, such as aprotinin and E64, blocked the increased chemotaxis, while cytoplasmic $Ca^{2+}$ influx mediated by these chemokines was inhibited by DpE. These results indicate that DpE increases the chemotactic activity of THP-1 cells in response to CC chemokines by regulating the cells' protease-dependent mechanism. This finding may be useful in identifying the pathogenesis of allergic diseases induced by Der p.

• Architectural research
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• v.9 no.2
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• pp.37-45
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• 2007

The proliferation of the House Dust Mite(HDM) is affected by temperature, humidity, ventilation, etc. Measuring temperature and humidity was performed at the very location where dust samplings take place and where they live in reality together with temperature and humidity of the ambient of the room. There has been discussion over the key environment factor of HDM survival; absolute humidity or relative humidity. It seems that relative humidity is the more important determinant for the mite's survival through the analysis of previous studies. Temperature, humidity, ventilation rate and Der P1 were measured in 4 flats in London. Mite allergen was detected in every house. Levels of Der P1 varied between <100ng/g and 22,778ng/g. Flats with high relative humidity(>50%) and poor ventilation(<0.5ach) showed higher levels of mite allergen than flats with lower humidity and adequate air change rate. Questionnaire survey was conducted and the result helped to confirm the findings from monitoring of environmental factors and the dust sampling.

• IMMUNE NETWORK
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• v.13 no.6
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• pp.295-300
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• 2013

Der f 2 is the group 2 major allergen of a house dust mite (Dermatophagoides farinae) and its function has been recently suggested. To determine the optimal condition of sensitization to recombinant Der f 2 (rDer f 2) in murine model of asthma, we compared the effectiveness with different adjuvants in BALB/c and C57BL/6 mice. Mice from both strains sensitized with rDer f 2 by intraperitoneal injection or subcutaneous injection on days 1 and 14. The dosage was $20{\mu}g$. Freund's adjuvants with pertussis toxin (FP) or alum alone were used as adjuvants. On days 28, 29, and 30, mice were challenged intranasally with 0.1% rDer f 2. We evaluated airway hyperresponsivenss, eosinophil proportion in lung lavage, airway inflammation, and serum allergen specific antibody responses. Naive mice were used as controls. Airway hyperresponsiveness was increased in C57BL/6 with FP, and BALB/c with alum (PC200: $13.5{\pm}6.3$, $13.2{\pm}6.7$ vs. >50 mg/ml, p<0.05). The eosinophil proportion was increased in all groups; C57BL/6 with FP, BALB/c with FP, C57BL/6 with alum, BALB/c with alum ($24.8{\pm}3.6$, $20.3{\pm}10.3$, $11.0{\pm}6.9$, $5.7{\pm}2.8$, vs. $0.0{\pm}0.0$%, p<0.05). The serum allergen specific IgE levels were increased in C57BL/6 with FP or alum (OD: $0.8{\pm}1.4$, $1.1{\pm}0.8$, vs. $0.0{\pm}0.0$). C57BL/6 mice were better responders to rDer f 2 and as for adjuvants, Freund's adjuvant with pertussis toxin was better.

• Journal of Environmental Health Sciences
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• v.38 no.3
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• pp.204-212
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• 2012

Objectives: The purpose of this study was to determine house dust mite concentrations in living rooms and bedding materials in atopic case-control groups. Methods: Fifty four homes with children suffering atopic diseases as cases and fifty one homes without atopic diseases as controls were selected after diagnosis at three elementary schools in Ulsan City. Dust samples were collected from the living rooms and bedding materials in each home during summer and winter with a vacuum cleaner and analyzed for house dust mites using enzyme-linked immunosorbent assay (ELISA). Environmental factors and family history were surveyed during sampling. Results: Both species of house dust mite Dermatophagoides farina (Der f 1) and Dermatophagoides pteronyssinus (Der p 1) were found in all homes. Derf1 concentrations were much higher than Der P1 concentrations, both in atopic homes (1518.9 vs. 27.0 ng/g. dust, respectively) and non-atopic homes (810.8 vs. 44.3 ng/g. dust, respectively). Der f 1 concentrations were significantly higher in the atopic group than in the non-atopic group (atopic: 1518.9 ng/g.dust, non-atopic: 810.8 ng/g.dust, p = 0.035). However, total house dust mite Der p 1 concentrations were significantly higher in the non-atopic group than in the atopic group (atopic: 27.0 ng/g.dust, non-atopic: 44.3 ng/g.dust, p = 0.035). Multiple regression implied that mothers with family history of atopic diseases (OR = 4.79, 95% CI = 1.81-12.69), Der f 1 concentrations (OR = 1.74, 95% CI = 1.07-2.81), and air freshener use (OR = 4.60, 95% CI = 1.72-12.34) had significant associations with atopic children. Conclusion: House dust mite Der f 1 concentrations were associated with atopic children. This study suggests that parents should reduce house dust mite Der f 1 concentrations through environmental controls.

• Journal of Genetic Medicine
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• v.7 no.1
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• pp.82-86
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• 2010

Jumping translocations (JT) are chromosomal rearrangements involving one donor chromosome and several recipient chromosomes. While JTs are frequently observed as acquired chromosomal abnormalities in hematologic malignancies, constitutional JTs are only rarely reported. We report two cases of constitutional JT in chorionic villi derived from the products of conception. The karyotype of the first case was 46,XY,add(18)(p11.1)[61]/45,XY,der(18;21)(q10;q10)[32]/46,XY,-18,+mar[16]/46,XY,i(18)(q10)[9]/45,XY,der(15;18)(q10;q10)[6]/46,XY,+1,dic(1;18)(p22;p11.1)[2]/45,XY,der(13;18)(q10;q10)[1]/46,XY[32]. The donor was a chromosome 18. The recipient chromosomes were chromosomes 1, 13, 15, 18 and 21. In the second case, the karyotype was 46,XY,der(22)t(9;22)(q12;q13)[22]/46,XY,der(22)t(1;22)(q21;q13)[13]/46,XY,add(22)(q13)[5]/46 XY[23]. The donor was a chromosome 22 and recipients were chromosomes 1 and 9. Both cases were de novo. The breakpoints of chromosomes were mostly in centromeric regions, pericentromeric regions, or telomeric regions. Normal cell lines were observed in both cases. This report supports the prior findings that the unstable nature of JT, resulting in chromosomal imbalance, most likely contributed to these early miscarriages.

• Parasites, Hosts and Diseases
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• v.46 no.3
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• pp.187-189
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• 2008

House dust mites produce inhalant allergens of importance to allergic patients, We measured the major group 1 allergens, Der p 1 and Der f 1, from the house dust mites Dermatophagoides pteronyssinus and Dermatophagoides farina, respectively in 100 randomly selected domestic homes from Cheonan, Korea, Dust samples were collected by vacuuming from the living room floor and 1 mattress in each home, Der p 1 and Der f 1 were measured by double mono-clonal ELISA. Der p 1 levels were very low, with geometric mean levels for floors and mattresses being $0.11\;{\mu}g/g$ (range: 0.01-4.05) and $0.14\;{\mu}g/g$ (range: 0.01-30.0), respectively. Corresponding levels of Der f 1 were higher, $7.46\;{\mu}g/g$ (range: 0.01-262.9) and $10.2\;{\mu}g/g$ (range: 0.01-230.9) for floors and mattresses, respectively. D. farinae appears to be the dominant house dust mite in Cheonan.