• 제목/요약/키워드: Del-1

검색결과 385건 처리시간 0.022초

A note on buckling and vibration of clamped orthotropic plates under in-plane loads

  • Felix, D.H.;Bambill, D.V.;Rossit, C.A.
    • Structural Engineering and Mechanics
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    • 제39권1호
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    • pp.115-123
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    • 2011
  • The present work deals with obtaining the critical buckling load and the natural frequencies of clamped, orthotropic, rectangular thin plates subjected to different linear distributed in-plane forces. An analytical solution is proposed. Using the Ritz method, the dependence between in-plane forces and natural frequencies are estimated for various plate sizes, and some results are compared with finite element solutions and where possible, comparison is made with previously published results. Beam functions are used as admissible functions in the Ritz method.

수리논리학의 역사적 배경과 괴델 (A Historical Background of Mathematical Logic and $G{\ddot{o}}del$)

  • 박창균
    • 한국수학사학회지
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    • 제21권1호
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    • pp.17-28
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    • 2008
  • 이 글의 목적은 수리논리학의 역사적 배경을 소개하려는 것이다. 각각 발전해온 수학과 논리학이 19세기 중엽에 하나로 합쳐지면서 엄청난 시너지 효과를 가져왔다. 그 후 논리학의 '수학화'는 탄력을 받아 진행되었고, 다른 한편으로는 수학도 논리로 환원시키려는 움직임이 일어났다. 이러한 흐름 속에서 괴델은 산수를 포함하는 무모순인 형식체계는 불완전하다는 것을 증명함으로써 형식주의의 한계를 보여주었다.

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Alagille 증후군에서 Jagged1 돌연변이 (Jagged1 mutation analysis in Alagille syndrome patients)

  • 고재성;양혜란;김경모;서정기
    • Clinical and Experimental Pediatrics
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    • 제49권5호
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    • pp.519-522
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    • 2006
  • 목 적 : Alagille 증후군은 간, 심장, 눈, 척추, 얼굴 모양 등 여러 장기에 이상을 일으키며 상염색체 우성으로 유전되는 질환이다. Alagille 증후군의 유전자인 JAG1은 Notch 수용체에 대한 리간드를 만든다. 이 연구의 목적은 우리나라 Alagille 증후군 환자에서 JAG1 유전자의 돌연변이를 찾아내는 것이다. 방 법 : Alagille 증후군으로 확진 받은 6명의 말초혈액 백혈구에서 DNA를 추출하여 JAG1 유전자에 대하여 중합효소연쇄 반응 및 정제 후 직접 염기서열 분석하였다. 결 과 : 2개의 새로운 frameshift 돌연변이가 발견되었다. 4세에 간세포암이 발생한 환자에서 엑손 2에서 118delC이 발견되었다. 한 환자에서는 엑손 7에서 999-1000delTG이 발견되었는데, 2개 돌연변이들은 정지코돈을 만들었다. 결 론 : 우리나라 Alagille 증후군 환자에서 단백이 잘라져 기능을 못하는 frameshift 돌연변이를 찾아내었다.

Identification of Germline BRCA1 Mutations among Breast Cancer Families in Northeastern Iran

  • Kooshyar, Mohammad Mahdi;Nassiri, Mohammadreza;Mahdavi, Morteza;Doosti, Mohammad;Parizadeh, Amirreza
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권7호
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    • pp.4339-4345
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    • 2013
  • Background: The purpose of this study was to evaluate the prevalence of BRCA1 (MIM: 113705) founder mutations in familial breast cancer (BC) patients with high risks in Iran. BRCA1 is among the cancer susceptibility genes best known for high penetrance mutations. BRCA1 genotyping is now used to determine patient counseling, management decisions, and prognosis of this syndrome. Materials and Method: Thirty nine patients with clinical BC and 29 high risk healthy women, related to the patients, participated in the study. DNA from blood samples was extracted and analyzed by PCR and SSCP methods in order to find 185delAG and 5382insC founder mutations. In addition, a 251bp fragment of BRCA1's exon 11 was amplified and analyzed for determination of new mutations. Results: The data indicated the presence of 185delAG and 5382insC founder mutations in both groups studied. Two out of 39 BC patients (5.1%) and one out of 29 relatives (3.4%) were suspected to be carriers of 185delAG mutations. However, we found only one patient (2.6%) to be a carrier of a 5382insC mutation. Also, 2 women (5.1%) of the patient group and 3 n (10.3%) of relatives group were identified as carriers of unclarified mutations in the 251bp fragment of the BRCA1 gene. The carriers of BRCA1 founder mutations have a high lifetime risk of breast cancer. Conclusions: Therefore, these data are useful in counseling of individuals with a significant family history of breast cancer.

Breast Cancer Association with CYP1A2 Activity and Gene Polymorphisms - a Preliminary Case-control Study in Tunisia

  • Ayari, I;Arnaud, MJ;Mani, A;Pavanello, S;Saguem, S
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권8호
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    • pp.3559-3563
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    • 2015
  • The aim of the present study was to evaluate the relative contribution of CYP1A2 isoforms (-3860 G/A, -2467T/delT and -163C/A) in control subjects and breast cancer patients to the metabolism of caffeine in human liver. Restriction fragment length polymorphism analysis of PCR-amplified Fragments (PCR-RFLP) was used for the genotyping of CYP1A2 SNPs and HPLC allowed the phenotyping through the measurement of CYP1A2 activity using the 17X + 13X + 37X/137X urinary metabolite ratio (CMR) and plasma caffeine half life (T1/2). The CYP1A2 -3860A genotype was associated with a decreased risk of breast cancer. In contrast, distributions of the CYP1A2 -2467T/delT or -2467delT/delT and -163A/C or A/A genotypes among breast cancer patients and controls were similar. When the genotype and phenotype relationship was measured by comparing the mean CMR ratios and caffeine half life within the genotype groups between subjects and breast cancer patients, there were no significant differences except for -3860 A, most of them being homozygous for the -3860 G/G SNP and had a significant higher mean CMR ratio and half life than those with -3860 G/A (P=0.02). The results of this preliminary study show a significant association between CP1A2 -3860 G variant and CYP1A2 phenotype which must be confirmed by further large-size case-control studies.

Current Evidence on the Relationship Between Two Polymorphisms in the NBS1 Gene and Breast Cancer Risk: a Meta-analysis

  • Zhang, Zhi-Hua;Yang, Lin-Sheng;Huang, Fen;Hao, Jia-Hu;Su, Pu-Yu;Sun, Ye-Huan
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권11호
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    • pp.5375-5379
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    • 2012
  • Introduction: Published studies on the association between Nijmegen breakage syndrome 1(NBS1) gene polymorphisms and breast cancer risk have been inconclusive, and a meta-analysis was therefore performed for clarification. Methods: Eligible articles were identified by a search of MEDLINE and EMBASE bibliographic databases for the period up to March 2012. The presence of between-study heterogeneity was investigated using the chi-square-based Cochran's Q statistic test. When there was statistical heterogeneity, the random effects model was chosen; otherwise, fixed effects estimates were reported as an alternative approach. Results: A total of 11 eligible articles (14 case-control studies) were identified, nine case-control studies were for the 657del5 mutation (7,534 breast cancer cases, 14,034 controls) and five case-control studies were for the I171V mutation (3,273 breast cancer cases, 4,004 controls). Our analysis results indicated that the 657del5 mutation was associated with breast cancer risk (carriers vs. non-carriers: pooled OR =2.63, 95% CI: 1.76-3.93), whereas the I171V mutation was not (carriers vs. non-carriers: pooled OR =1.52, 95% CI: 0.70-3.28). Conclusion: The present meta-analysis suggests that the 657del5 gene mutation in the NBS1 gene plays a role in breast cancer risk, while the I171V mutation does not exert a significant influence.

ON PILLAI'S PROBLEM WITH TRIBONACCI NUMBERS AND POWERS OF 2

  • Bravo, Jhon J.;Luca, Florian;Yazan, Karina
    • 대한수학회보
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    • 제54권3호
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    • pp.1069-1080
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    • 2017
  • The Tribonacci sequence ${\{T_n}\}_{n{\geq}0}$ resembles the Fibonacci sequence in that it starts with the values 0, 1, 1, and each term afterwards is the sum of the preceding three terms. In this paper, we find all integers c having at least two representations as a difference between a Tribonacci number and a power of 2. This paper continues the previous work [5].

GENERALIZED PADOVAN SEQUENCES

  • Bravo, Jhon J.;Herrera, Jose L.
    • 대한수학회논문집
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    • 제37권4호
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    • pp.977-988
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    • 2022
  • The Padovan sequence is the third-order linear recurrence (𝓟n)n≥0 defined by 𝓟n = 𝓟n-2 + 𝓟n-3 for all n ≥ 3 with initial conditions 𝓟0 = 0 and 𝓟1 = 𝓟2 = 1. In this paper, we investigate a generalization of the Padovan sequence called the k-generalized Padovan sequence which is generated by a linear recurrence sequence of order k ≥ 3. We present recurrence relations, the generalized Binet formula and different arithmetic properties for the above family of sequences.

카니발의 광장: 알모도바르 영화 속의 마드리드 (La plaza pública carnavalesca: Madrid en el cine de Pedro Almodóvar)

  • 임호준
    • 이베로아메리카
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    • 제12권1호
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    • pp.349-374
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    • 2010
  • En realidad ningún otro cineasta español que Pedro Almodóvar ha centrado tan obsesivamente en Madrid. Casi todas sus obras se ocupan de la capital de España como espacio cinematográfico. Como uno de los protagonistas de La Movida, Almodóvar es un producto de Madrid de la Transición que dió luz a la nueva sociedad democrática. En principio, Madrid en las películas de Almodóvar se convierte en un espacio carnavalesco desde la perspectiva bajtiniana. El crítico ruso ha exaltado la plaza pública de los pueblos medievales europeos como el espacio carnavalesco en el que los contactos libres y familiares se realizan y el principio de lo corporal y lo material predomina. Para Bajtín, el carnaval es básicamente un rito político en el que el individuo parece dotado de una segunda vida que le permite establecer nuevas relaciones verdaderamente humanas con sus semejantes sin ninguna represión. Así que en el mundo carnavalesco todo lo sagrado, lo oficial y lo privilegiado se destronan, y en cambio lo grosero, lo extra-oficial y lo bajo se reivindican. Como los participantes del carnaval, los personajes de Almodóvar disfrutan de una segunda vida en un Madrid del mundo al revés. Por otra parte, la representación carnavalesca de Madrid tiene una tradición rica y larga en el arte español. Entre muchos artistas Goya, Arniches, Valle-Inclán y Buñuel son los antecedentes destacados de esta tradición. Así pues se puede concluir que la estética del cine de Almodóvar está anclada en la tradición hispánica del carnavalismo más bien que la estética global de la posmodernidad.

Population-Based Newborn Hearing Impairment Screening Test Using GJB2 Mutation Analysis

  • Lee, Kyung-Ok;Jeong, Su-Jin;Byun, Ji-Young;Kim, Jeong-Sook;Lee, Hye-Jung;Seong, Hye-Soon;Kim, Kyung-Tae
    • 대한임상검사과학회지
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    • 제39권2호
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    • pp.113-121
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    • 2007
  • 선천성난청은 비교적 흔한(1/1,000) 유전성질환으로 여러 유전자와 관련이 있으며, 최근에는 connexin 26 단백질내의 GJB2 유전자 돌연변이와의 관련성이 보고되고 있다. 유전질환을 예측하기 위한 유전자선별검사를 임상에 적용하기 위해서는 각 해당 국가별로 정상인에서 유전자돌연변이의 빈도를 구하고, 환자의 결과를 비교하여 활용성을 검토한 후 사용하여야 한다. 본 연구에서는 청력검사(TEOAE)가 정상인 신생아에서 GJB2 유전자 돌연변이 빈도를 구하여 screening test를 위한 한국인의 database를 수립하고자 하였다. 검체로는 437 명의 건강한 신생아의 발꿈치를 천자하여 얻은 혈액을 이용하였고, DNA는 Intron 사의 킷트를 사용하여 추출하였으며, GJB2 PCR을 실시한 후 증폭산물(783 bps)은 2% agarose gel로 전기영동을 실시하였고, DNA 자동염기서열분석기를 이용하여 분석을 실시하였다. 총 437명의 한국인 신생아에서 GJB2 유전자 중 8곳의 돌연변이(35delG, 167delT, 235delC, V27I, V37I, M34T, E114G, I203T)를 분석하였으며, 이 중 5곳에서 돌연변이가 발견되었다. 총 437명 중 301명(68.9%)에서 GJB2 유전자돌연변이가 발견되었는데, 그 중 154명이 단일돌연변이였다. V27I 변이가 271명으로 가장 많이 발견되었으며, 대부분의 V27I 변이는 E114G 변이와 함께 나타났다. E114G 변이는 총 146명, I203T 변이는 17명, V37I 변이는 14명, 235delC 변이는 1명의 순으로 나타났다. 이중돌연변이의 대부분은 V27I/E114G였으며, V27I/I203T는 3명에서 나타났고, 삼중돌연변이 V27I/E114G/I203T는 1명에서 발견되었다. 본 연구결과, PCR을 이용한 자동염기분석검사는 GJB2 유전자의 돌연변이 검출에 매우 유용하며, 본 결과는 향 후 신생아 난청선별검사를 위한 한국인의 database로 활용될 수 있을 것으로 사료된다.

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