• Molecules and Cells
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• 제41권8호
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• pp.753-761
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• 2018

Tumor necrosis factor receptor-associated factor 6 (TRAF6) is identified as a signaling adaptor protein that regulates bone metabolism, immunity, and the development of several tissues. Therefore, its functions are closely associated with multiple diseases. TRAF6 is also involved in the regulation of hematopoiesis under steady-state conditions, but the role of TRAF6 in modulating hematopoietic stem and progenitor cells (HSPCs) during the developmental stages remains unknown. Here, we report that the deletion of TRAF6 in hematopoietic lineage cells resulted in the upregulation of HSPCs in the fetal liver at the prenatal period. However, in the early postnatal period, deletion of TRAF6 drastically diminished HSPCs in the bone marrow (BM), with severe defects in BM development and extramedullary hematopoiesis in the spleen being identified. In the analysis of adult HSPCs in a BM reconstitution setting, TRAF6 played no significant role in HSPC homeostasis, albeit it affected the development of T cells. Taken together, our results suggest that the role of TRAF6 in regulating HSPCs is altered in a spatial and temporal manner during the developmental course of mice.

• 한국컴퓨터정보학회논문지
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• 제15권10호
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• pp.113-120
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• 2010

본 논문에서는 비디오 프록시 서버의 제한된 저장 공간을 효율적으로 활용하기 위한 시간 제약 다중 요청 기법을 제안한다. 제안하는 기법은 요청된 동영상 데이터를 전송받아 사용자에게 전송하고 비디오 프록시 서버에 일시적으로 저장한다. 이때 일시적으로 저장된 동영상 데이터는 설정된 시간 내에서 발생되는 사용자의 요청의 상태에 따라 저장장치에서 삭제되거나 저장된다. 또한 새롭게 요청된 동영상의 저장 공간을 확보하기 위해서 저장장치에 저장되어 있는 동영상 세그먼트 중 요청 가능성이 가장 낮은 세그먼트를 선정하고 제거한다. 이를 위해 사용자에 의해 주로 요청되는 동영상 세그먼트 부분인 전방 클래스와 요청되지 않았거나 요청될 가능성이 적은 세그먼트 부분인 후방 클래스로 분리한다. 분리된 클래스 중 후방 클래스에서 가장 오래전에 요청된 세그먼트를 선정하여 삭제함으로써 제한된 공간을 효율적으로 활용한다. 실험을 통해 제안하는 방법이 기존의 방법들 보다 높은 적중률을 보이는 동시에 보다 적은 삭제 횟수를 보인다는 것을 확인한다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권4호
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• pp.1286-1306
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• 2022

Searchable symmetric encryption (SSE) provides a safe and effective solution for retrieving encrypted data on cloud servers. However, the existing SSE schemes mainly focus on single keyword search in single client, which is inefficient for multiple keywords and cannot meet the needs for multiple clients. Considering the above drawbacks, we propose a scheme enabling dynamic multi-client and Boolean query in searchable symmetric encryption for cloud storage system (DMC-SSE). DMC-SSE realizes the fine-grained access control of multi-client in SSE by attribute-based encryption (ABE) and novel access control list (ACL), and supports Boolean query of multiple keywords. In addition, DMC-SSE realizes the full dynamic update of client and file. Compared with the existing multi-client schemes, our scheme has the following advantages: 1) Dynamic. DMC-SSE not only supports the dynamic addition or deletion of multiple clients, but also realizes the dynamic update of files. 2) Non-interactivity. After being authorized, the client can query keywords without the help of the data owner and the data owner can dynamically update client's permissions without requiring the client to stay online. At last, the security analysis and experiments results demonstrate that our scheme is safe and efficient.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권2호
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• pp.558-579
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• 2021

The cloud storage provides flexible data storage services for data owners to remotely outsource their data, and reduces data storage operations and management costs for data owners. These outsourced data bring data security concerns to the data owner due to malicious deletion or corruption by the cloud service provider. Data integrity verification is an important way to check outsourced data integrity. However, the existing data verification schemes only consider the case that a verifier launches multiple data verification challenges, and neglect the verification overhead of multiple data verification challenges launched by multiple verifiers at a similar time. In this case, the duplicate data in multiple challenges are verified repeatedly so that verification resources are consumed in vain. We propose a duplicate data verification algorithm based on multiple verifiers and multiple challenges to reduce the verification overhead. The algorithm dynamically schedules the multiple verifiers' challenges based on verification time and the frequent itemsets of duplicate verification data in challenge sets by applying FP-Growth algorithm, and computes the batch proofs of frequent itemsets. Then the challenges are split into two parts, i.e., duplicate data and unique data according to the results of data extraction. Finally, the proofs of duplicate data and unique data are computed and combined to generate a complete proof of every original challenge. Theoretical analysis and experiment evaluation show that the algorithm reduces the verification cost and ensures the correctness of the data integrity verification by flexible batch data verification.

• 지능정보연구
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• 제9권2호
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• pp.51-63
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• 2003

Collaborative filtering is one of the methodologies that are most widely used for recommendation system. It is based on a data matrix of each customer's preferences of products. There could be a lot of missing values in such preference data matrix. This incomplete data is one of the reasons to deteriorate the accuracy of recommendation system. There are several treatments to deal with the incomplete data problem such as case deletion and single imputation. Those approaches are simple and easy to implement but they may provide biased results. Multiple imputation method imputes m values for each missing value. It overcomes flaws of single imputation approaches through considering the uncertainty of missing values. The objective of this paper is to suggest multiple imputation-based collaborative filtering approach for recommendation system to improve the accuracy in prediction performance. The experimental works show that the proposed approach provides better performance than the traditional Collaborative filtering approach, especially in case that there are a lot of missing values in dataset used for recommendation system.

• Journal of Genetic Medicine
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• 제5권1호
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• pp.15-20
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• 2008

목 적 : 듀시엔/베커형 근이영양증(Duchenne and Becker type muscular dystrophy; DMD/BMD)은 남아에게 나타나는 일반적인 X 염색체 연관 유전성 근육 질환으로 DMD(dystrophin) 유전자의 돌연변이로 인해 생긴다. 그 중 큰 exon 결실이 전체 DMD 환자의 약 50-60%에서 발견된다. 이 유전자의 돌연변이를 찾기 위해 여러 방법들이 사용되고 있지만 결실 돌연변이를 찾아내기 위한 가장 일반적인 방법으로 복합적 중합효소연쇄반응을 이용하고 있다. 하지만 이 방법의 단점은 하나의 시험관 안에 복합적인 시발체가 존재하여 정확한 반응 조건을 찾기 힘들 뿐 아니라 시발체 상호간의 간섭으로 중합효소 연쇄반응의 비특이적 생성물을 빈번하게 일으켜 잘못된 음성 또는 양성 결과를 가져올 수 있다. 이런 문제를 보완하고자 Dual Primer Oligonucleotide(DPO) 방법을 도입하였다. DPO는 polydeoxyinosine 연결에 의해 두 영역으로 분리된 올리고뉴클레오티드(oligonucleotide)로 표적 DNA 염기서열과의 교잡반응에 높은 특이적 반응을 보여 복합 중합효소 연쇄반응의 정확도를 높여준다. 본 연구에서는 3 그룹을 대상군으로 DMD 유전자의 결실돌연변이 검색을 위한 DPO-복합 중합효소 연쇄반응법의 특이성과 민감성을 알아보고자 하였다. 방 법 : 50명의 건강한 남자 대조군, 50명의 결실 돌연변이를 갖고 있는 양성반응 환자그룹 그리고 20명의 결실 돌연변이를 가지고 있지 않은 음성반응 환자 그룹으로 구성된 3 그룹을 대상으로 DPO-복합 중합효소 연쇄반응법을 이용하여 실험하였다. 이들 120명의 실험군 모두 PMter영역과 exon 3, 4, 6, 8, 12, 13, 17, 19, 43-48, 50-52, 60을 포함하는 18개의 exon에서의 결실의 여부와 결실 범위를 확인하였다. 결 과 : DPO-복합 중합효소 연쇄반응법은 결실 여부를 발견하는데 100%의 특이성과 민감성을 보였다. 하지만 결실 범위의 결정에는 97.1%의 민감성과 특이성을 보였다. 결 론 : DPO-복합 중합효소 연쇄반응법은 기존의 복합 중합효소 연쇄반응법 보다 높은 분석 확실성을 보일뿐 아니라 빠르고 저렴한 비용으로 쉽게 할 수 있기 때문에 듀시엔/베커형 근이영양증 환자의 DMD 유전자의 결실돌연변이 여부를 확인하는데 유용한 방법이다.

• Journal of Crop Science and Biotechnology
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• 제10권4호
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• pp.237-242
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• 2007

Genome duplication(i.e. polyploidy) is a common phenomenon in the evolution of plants. The objective of this study was to achieve a comprehensive understanding of genome duplication for SNP discovery by Thymine/Adenine(TA) cloning for confirmation. Primer pairs were designed from 793 EST contigs expressed in the roots of a supernodulating soybean mutant and screened between 'Pureunkong' and 'Jinpumkong 2' by direct sequencing. Almost 27% of the primer sets were failed to obtain sequence data due to multiple bands on agarose gel or poor quality sequence data from a single band. TA cloning was able to identify duplicate genes and the paralogous sequences were coincident with the nonspecific peaks in direct sequencing. Our study confirmed that heterogeneous products by the co-amplification of a gene family member were the main cause of obtaining multiple bands or poor quality sequence data in direct sequencing. Counts of amplified bands on agarose gel and peaks of sequencing trace suggested that almost 27% of nonrepetitive soybean sequences were present in as many as four copies with an average of 2.33 duplications per segment. Copy numbers would be underestimated because of the presence of long intron between primer binding sites or mutation on priming site. Also, the copy numbers were not accurately estimated due to deletion or tandem duplication in the entire soybean genome.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제17권4호
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• pp.257-262
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• 2014

Severe combined immunodeficiency (SCID) is a life-threatening syndrome of recurrent infections and gastro-intestinal alterations due to severe compromise of T cells and B cells. Clinically, most patients present symptoms before the age of 3 months and without intervention SCID usually results in severe infections and death by the age of 2 years. Its association with intestinal anomalies as multiple intestinal atresias (MIA) is rare and worsens the prognosis, resulting lethal. We describe the case of a four year-old boy with SCID-MIA. He presented at birth with meconium peritonitis, multiple ileal atresias and underwent several intestinal resections. A targeted Sanger sequencing revealed a homozygous 4-bp deletion ($c.313{\Delta}TATC$; p.Y105fs) in tetratricopeptide repeat domain 7A (TTC7A). He experienced surgical procedures including resection and stricturoplasty. Despite parenteral nutrition-associated liver disease, the patient is surviving at the time of writing the report. Precocious immune system assessment, scrutiny of TTC7A mutations and prompt surgical procedures are crucial in the management.

• 한국화재소방학회논문지
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• 제28권2호
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• pp.69-75
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• 2014

본 연구에서는 방화발생에 영향을 미치는 요인을 도출하기 위하여 발생건수를 종속변수로 하고 경제 인구 사회적 요인을 독립변수로 하는 다중회귀분석을 실시하였다. 다중회귀분석은 선형함수, 준로그함수, 역준로그함수, 이중로그함수 4가지 함수형태에 대해 적용하였으며, 각 단계별로 변수의 선택과 제외를 고려하는 단계적선택 방식을 적용하였다. 다중공선성 문제와 자기상관 문제를 해결하기 위하여 분산확대지수(VIF)와 Durbin-Watson 계수 이용하였으며, 4가지 함수모형에 대하여 수정된 R 제곱(설명력) 값이 0.935 (93.5%)로 가장 값이 높고 통계적으로 유의한 선형함수모형을 최적의 모형으로 결정하고 모형에 대한 해석을 진행하였다. 선형함수모형 결과 방화발생에 영향을 미치는 요인은 범죄발생건수(0.829), 일반이혼율(0.151), 재정자주도(0.149), 소비자물가상승률(0.099) 순으로 도출되었다.

• 대한두경부종양학회지
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• 제14권1호
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• pp.20-26
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• 1998

Objectives: Deletion in the short arm of chromosome 3 is common in many human cancers, including sporadic and hereditary renal carcinomas, small cell lung carcinomas, non-small cell lung carcinomas, and carcinomas of the ovary, breast, and cervix. A high frequency of chromosomal aberrations in head and neck cancers involving chromosome 3p has also been reported. These findings suggest that multiple tumor suppressor genes may be present on the short arm of chromosome 3. Materials and Methods: To investigate the possibility of chromosome 3p deletions in the Korean head and neck cancer patients, we applied a polymerase chain reaction(PCR)-based Restriction Fragment Length Polymorphism analysis to the DNA samples of matched normal mucosa and head and neck squamous cell carcinomas from 19 patients. Results: In the 19 normal samples heterozygosity at the polymorphic loci varied: 6 at the D3F15S2 locus(on telomeric 3p21), 2 at the D3S32 locus(on centromeric 3p21), and 4 at the THRB locus(on centromeric 3p24). In 12 matched carcinoma specimens, LOH(loss of heterozygosity) was observed at D3F15S2 in 1 of 6(17%), D3S32 in 1 of 2(50%), and at THRB in 2 of 4 cases(50%). Conclusion: The frequency of chromosome 3p deletion in the Korean head and neck carcinomas appear as other country did.