• Clinical and Experimental Reproductive Medicine
• /
• v.44 no.4
• /
• pp.224-231
• /
• 2017

Objective: We studied the association between sperm DNA fragmentation (SDF) and several clinical in vitro fertilization outcomes. Methods: We retrospectively analyzed 169 consecutive fresh IVF cycles. Semen was collected on the day of oocyte retrieval, and we assessed standard semen parameters and the SDF level (by terminal deoxynucleotidyl transferase dUTP nick-end labeling). Poor ovarian response (POR) was defined as the collection of three or fewer mature oocytes. Oocytes were inseminated by the conventional method or intracytoplasmic sperm injection. Results: SDF did not affect the fertilization or pregnancy rate, but did have a significant effect on the miscarriage rate. In the miscarriage group (n = 10), the SDF level was significantly higher (23.9% vs. 14.1%) and number of mature oocytes was significantly lower (4.3 vs. 7.6) than in the live birth group (n = 45). Multiple regression analysis showed that SDF was an independent predictor of miscarriage (odds ratio, 1.051; 95% confidence interval, 1.001-1.104). The cutoffs for the SDF level and number of mature oocytes that could predict miscarriage were > 13% and ${\leq}3$, respectively. In the low-SDF group (${\leq}13%$), the miscarriage rate was similar in POR patients and those with a normal ovarian response (NOR; 14.2% vs. 4.3%). In the high-SDF group ( > 13%), the miscarriage rate was significantly higher in the POR group than in the NOR group (60.0% vs. 13.3%, p= 0.045). Conclusion: Our study demonstrated that a high SDF level ( > 13%) was associated with a high miscarriage rate, and that it mainly contributed to miscarriage in the POR group. The results suggest that SDF measurements should be considered in couples with POR in order to predict the prognosis of the pregnancy.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.47 no.4
• /
• pp.406-415
• /
• 2020

Silver diamine fluoride (SDF) is an effective and efficient agent for arresting dental caries. It can be useful in treating children with behavioral or medical limitations. The purpose of this study was to evaluate the antimicrobial effect of SDF by using salivary biofilm. Pellicle-like saliva coated structure was prepared by using unstimulated saliva. For developing cariogenic biofilm, Streptococcus mutans was added to the mixture of pooled saliva and inoculated into a saliva coated glass or chamber. SDF was applied to cariogenic biofilm to evaluate the antimicrobial effect of SDF. As time passed, total bacteria and S. mutans were reduced after application of SDF (p < 0.000). Confocal laser scanning microscope also showed the increment of the ratio of dead cell. As a result of experiment using enamel and dentin of primary teeth, it was confirmed that the growth of cariogenic biofilm was inhibited when the SDF was treated (p = 0.029 each). This study showed excellent anti-microbial effect of SDF. And anti-caries effect in clinical practice can be expected.

• The Journal of the Korea Contents Association
• /
• v.4 no.4
• /
• pp.205-213
• /
• 2004

In this paper, we proposed a wavelet phase-only filter modulation synthetic discriminant function joint transform correlator(WPOfSDF-JTC) for scale invariant pattern recognition, and an improved algorithm to reduce the filter synthesis time. Computer simulation showed that the proposed filter has better SNR than CWMF if input image has random noise and the improved synthesis algorithm can reduce the iteration time. We used frequency selective JTC to solve the problem of the optical alignment and eliminate the autocorrelation and crosscorrelation between each input image.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.22 no.2
• /
• pp.392-400
• /
• 1997

In this paper we porposed WCHF-fSDF filter to obtain a roration and scale-invariant correlation output. WCHF-fSDF filter is synthesized by each single CHF exttracted from scale-changed and wavelet tranformed imagesfor a refereence image as tranining images. The wavelet transform is defined as the correlation of an input image with a wavelet function. Therefore two 4f optical correlation systems are needed for pattern recognition using wavelet transform. We here include the wavelet function for the input image in the process of the proposed filter design and substitute the two 4f optical correlation system with a single 4f optical correlation system. The Performances of the proposed filter are compared with conventional CHF-SDF, POCHF-SDF filters through the computer simulation. The results of computer simulation show that the proposed filter has the rotation and scale-invariant correlation output and it has better performances than thoseof the conventioanl filters.

• Molecules and Cells
• /
• v.22 no.3
• /
• pp.308-313
• /
• 2006

Stromal cell-derived factor (SDF-1) is a CXC chemokine that selectively activates the CXCR4 chemokine receptor. Fibronectin is an intracellular matrix component that binds integrin and mediates cell-matrix adhesion. Activation of the integrin receptor can occur in two ways: by ligand binding (outside-in signaling), and in response to intracellular events (inside-out signaling). In the current study we showed that SDF-$1{\alpha}$ inhibited adhesion of T lymphocyte Jurkat cells resulting from binding high concentrations of fibronectin as well as that of THP-1 monocytes. The effect of SDF-$1{\alpha}$ on fibronectin-mediated adhesion was partly reversed by the CXCR4 receptor antagonist T140. Our results suggest that an SDF-1/CXCR4 signal pathway modulates fibronectin-mediated lymphocytes adhesion.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2024.01a
• /
• pp.371-374
• /
• 2024

본 논문에서는 PBD(Position-based dynamics)를 이용한 옷감 시뮬레이션에서 페이스(Face) 및 에지(Edge)의 충돌/접촉을 처리할 때 나타나는 표면 떨림 문제를 SDF(Signed Distance Field) 접근법을 통해 안정적으로 해결할 수 있는 기법을 제안한다. 충돌 제약 조건을 이용한 충돌처리에서 나타나는 옷감 시뮬레이션의 떨림 현상을 개선하기 위해 본 논문에서는 페이스 및 에지 내부에 존재하는 충돌 지점의 속도를 충돌 법선 방향과 접선 방향으로 나누어 계산하는 과정을 거치며, 그 운동량을 페이스 및 에지에 포함된 연결된 정점(Vertex)에 전달한다. 본 논문에서 제안하는 기법은 일반적인 SDF 기반 충돌 처리에서 나타나는 충돌 시 떨림 현상을 개선하며, 기존의 방법보다 안정적인 SDF 충돌처리가 가능하기 때문에 다양한 변형체 재질을 시뮬레이션 할 때 활용될 수 있다.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.3
• /
• pp.570-576
• /
• 2004

In this paper, we design the IFFT/FFT (Inverse fast Fourier Transform/Fast Fourier Transform) modules for IEEE 802.11a-1999, which is a standard of the High-speed Wireless LAN using the OFDM (Orthogonal Frequency Division Multiplexing). The designed IFFT/FFT is the 64-point FFT to be compatible with IEEE 802.11a and the pipelined architecture which needs neither serial-to-parallel nor parallel-to-serial converter. We compare four types of IFFT/FFT modules for the hardware complexity and operation : R22SDF (Radix-2 Single-path Delay feedback), the R2SDF (Radix-2 Single-path Delay feedback), R2SDF (Radix-4 Single-path Delay Feedback), and R4SDC (Radix-4 Single-path Delay Commutator). In order to minimize the error, we design the IFFT/FFT module to operate with additional decimal parts after butterfly operation. In case of the R22SDF, the IFFT/FFT module has 44,747 gate counts excluding RAMs and the minimized error rate as compared with other types. And we know that the R22SDF has a small hardware structure as compared with other types.

• Journal of Korea Society of Industrial Information Systems
• /
• v.9 no.2
• /
• pp.81-88
• /
• 2004

For scale and rotation invariant pattern recognition of images with noise, an optical wavelet CHF-fSDF filter is proposed. Wavelet CHF-fSDF filter is synthesized by each single CHF extracted from scale-changed and wavelet transformed images for a referene image as training images. The proposed optical wavelet CHF-fSDF filter is the type of the matched filter so that it can use the structure of 4f optical correlation system. The results of computer simulation show that the proposed filter has the rotation and scale-invariant correlation output and it is useful in the noisy input.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.4 no.6
• /
• pp.1023-1041
• /
• 2010

In cognitive radio networks, cooperative spectrum sensing schemes are proposed to improve the performance of detecting licensees by secondary users. Commonly, the cooperative sensing can be realized by means of hard decision fusion (HDF) or soft decision fusion (SDF) schemes. The SDF schemes are superior to the HDF ones in terms of the detection performance whereas the HDF schemes are outperforming the SDF ones when the traffic overhead is taken into account. In this paper, a hybrid SFD-HDF cluster-based approach is developed to jointly exploit the advantages of SFD and HDF schemes. Different SDF schemes have been proposed and compared within a given cluster whereas the OR-rule base HDF scheme is applied to combine the decisions reported by cluster headers to a common receiver or base station. The computer simulations show promising results as the performance of the proposed scenario of hybridizing soft and hard fusion schemes is significantly outperforming other different combinations of conventional SDF and HDF schemes while it noticeably reduces the network traffic overhead.

• IMMUNE NETWORK
• /
• v.2 no.2
• /
• pp.86-90
• /
• 2002

Background: Host genetic polymorphisms in the HIV-1 co-receptor CCR5 and CCR2b and SDF-1, ligand for co-receptor CXCR4, have been known to be associated with the resistance of HIV infection and/or the delayed disease progression in HIV-infected patients. Methods: We examined the frequencies of SDF1-3'A and CCR2b-64I alleles of 354 Koreans including 100 HIV-uninfected persons, 13 discordant spouses of HIV-infected persons, and 241 HIV-infected persons. The genotyping assays of SDF1 and CCR2b genes were carried out by polymerase chain reaction-restriction fragment length polymorphism. Results: The frequencies of CCR2b-64I and SDF1-3'A alleles in Koreans were very high compared with Caucasians and blacks. Observed frequencies of CCR2b-64I and SDF1-3'A allelic variants were 25.1% and 28.7%, respectively. The frequency of the CCR2b-64I allele in Koreans was 2~4 times higher than those of other ethnic groups with the exception of Asian. The frequencies of CCR2b-64I and SDF1-3'A genotypes did not show the significant difference between HIV-infected and uninfected Koreans. However, the prevalence of CCR2b-64I genotype of the LTNP group was about two times higher than that of the remainder group (P< 0.05). Four (45%) out of 9 LTNPs (long-term nonprogressors) showed having the SDF1-3'A allele and 7 (78%) out of 9 LTNPs carried the CCR2b-64I allele. 3 (33%) out of 9 LTNPs had both SDF1-3'A and CCR2b-64I alleles. But none of 5 RPs (rapid progressors) appeared to have both SDF1-3'A and CCR2b-64I alleles. Conclusion: The different genetic backgrounds in study populations may affect the disease progression and the AIDS epidemic in each country. Further studies need to define whether high frequencies of CCR2b-64I and SDF1-3'A allelic variants may affect the HIV disease progression.