• Title/Summary/Keyword: Defect Density

Search Result 461, Processing Time 0.035 seconds

The effect of local application of thymoquinone, Nigella sativa's bioactive component, on bone healing in experimental bone defects infected with Porphyromonas gingivalis

  • Batug, Ayse Yilmaz;Tomruk, Ceyda Ozcakir;Guzel Elif;Ozdemir, İlkay;Duygu, Gonca;Kutan, Esma;Ulker, Gul Merve Yalcin;Arici, Fatma Ozen
    • Journal of Periodontal and Implant Science
    • /
    • v.52 no.3
    • /
    • pp.206-219
    • /
    • 2022
  • Purpose: This study was performed to evaluate the influence of local application of thymoquinone (TQ) on bone healing in experimental bone defects infected with Porphyromonas gingivalis (PG). Methods: Forty-two female rats were randomly divided into 6 groups. A bone defect was created on the right tibia of all animals. The PG, PG/collagen membrane (COL) and PG/TQ/COL groups were infected with PG. In the COL and PG/COL groups, the defects were covered with a COL; in the TQ/COL and PG/TQ/COL groups, the defects were covered with a TQ-containing COL. After 28 days, all animals were sacrificed. Quantitative measurements of new bone formation and osteoblast lining, as well as semiquantitative measurements of capillary density and tissue response, were analyzed. Furthermore, the presence of bacterial infections in defect areas was evaluated. Results: The new bone formation, osteoblast number, and capillary density were significantly higher in the TQ groups than in the control groups (P<0.001, P<0.001, and P<0.01, respectively). In a comparison between the TQ/COL group, with a TQ-containing COL (TQ/COL), and the PG-infected TQ-containing COL (PG/TQ/COL) group, the newly formed bone and capillary density were higher in the TQ/COL group (P<0.01). When the control group was compared to the PG, PG/COL, and PG/TQ/COL groups in terms of tissue response, the differences were statistically significant (P<0.001, P=0.02, and P=0.041, respectively). The intensity of the inflammatory cell reaction was higher in the PG, PG/COL, and PG/TQ/COL groups (P<0.05). Conclusions: Within the limitations of this study, the local application of a TQ-containing COL positively affected bone healing even if the bone defects were infected. The results suggest that TQ increased angiogenesis and showed promise for accelerating bone defect healing. Further research is warranted to support these findings and reach more definitive conclusions.

Cost-Driven Optimization of Defect-Avoidant Logic Mapping Strategies for Nanowire Reconfigurable Crossbar Architecture (Nanowire Reconfigurable Crossbar 구조를 위한 결함 회피형 로직 재할당 방식의 분석과 총 비용에 따른 최적화 방안)

  • Lee, Jong-Seok;Choi, Min-Su
    • Journal of KIISE:Computer Systems and Theory
    • /
    • v.37 no.5
    • /
    • pp.257-271
    • /
    • 2010
  • As the end of photolithographic integration era is approaching fast, numerous nanoscale devices and systems based on novel nanoscale materials and assembly techniques are recently emerging. Notably, various reconfigurable architectures with considerable promise have been proposed based on nanowire crossbar structure as the primitive building block. Unfortunately, high-density sys-tems consisting of nanometer-scale elements are likely to have numerous physical imperfections and variations. Therefore, defect-tolerance is considered as one of the most exigent challenges in nanowire crossbar systems. In this work, three different defect-avoidant logic mapping algorithms to circumvent defective crosspoints in nanowire reconfigurable crossbar systems are evaluated in terms of various performance metrics. Then, a novel method to find the most cost-effective repair solution is demonstrated by considering all major repair parameters and quantitatively estimating the performance and cost-effectiveness of each algorithm. Extensive parametric simulation results are reported to compare overall repair costs of the repair algorithms under consideration and to validate the cost-driven repair optimization technique.

A Study on Point Defect Induced with Neutron Irradiation (중성자 조사에 의해 생성된 점결함 연구)

  • 김진현;이운섭;류근걸;김봉구;이병철;박상준
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.3 no.3
    • /
    • pp.165-169
    • /
    • 2002
  • Silicon wafer is very important accuracy make use semiconductor device substrate. In this research, for the uniformity dopant density distribution obtained to Neutron Transmutation Doping on make use Si in P Doping study work. In this research. we irradiated neutron on FZ silicon wafers which had high resistivity (1000~2000 ${\Omega}$cm), HANARO reactor was utilized resistivity changes due to observed, the generation of neutron irradiation on point defect analyzed, point defect on resistivity changes inquire into the effect. Before neutron irradiation theoretical due to calculated 5 ${\Omega}$-cm, 20.1 ${\Omega}$-cm for HTS hole and 5 ${\Omega}$-cm, 26.5 ${\Omega}$-cm, 32.5 ${\Omega}$-cm for IP3 hole. After neutron irradiation through SRP measurement the designed resistivities were approached, which were 2.1 H-cm for HTS-1, 7.21 ${\Omega}$-cm for HTS-2, 1.79 ${\Omega}$-cm for IP-1, 6.83 ${\Omega}$-cm for IP-2, 9.23 ${\Omega}$-cm for IP-3, respectively. Also after neutron irradiation resistivity changes due to thermal neutron dependent irradiation hole types free.

  • PDF

The Effect of a Hydroxyapatite and 4-hexylresorcinol Combination Graft on Bone Regeneration in the Rabbit Calvarial Defect Model (가토의 두정골 결손부 모델에서 수산화인회석에 4-hexylresorcinol을 혼합하여 만든 인공합성골이식재의 골형성효과에 대한 연구)

  • Kim, Min Keun;Park, Yong Tae;Kim, Seong-Gon;Park, Young-Wook;Lee, Suk-Keun;Choi, Weon-Sik
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.34 no.6
    • /
    • pp.377-383
    • /
    • 2012
  • Purpose: The aim of this study was to evaluate the effect of 4-hexylresorcinol and hydroxyapatite combination graft on bone regeneration in the rabbit calvarial defect model. Methods: Ten New Zealand white rabbits were used for this study. Bilateral round shaped defects (diameter: 8.0 mm) were created on the parietal bone. 4-hexylresorcinol and hydroxyapatite combination graft material was grafted into the right parietal bone defect area (experimental). The left bone defect area was not filled with anything (control). The animals were sacrificed at 4 weeks and 8 weeks after grafting. A micro-computerized tomography of each specimen was taken, and the specimens were stained for histological analysis. Results: The average value of bone mineral density (BMD) and Bone volume (BV) was higher in the experimental group than in the control group at 4 weeks and 8 weeks after surgery. However, the difference was not statistically significant (P>0.05) at 8 weeks after grafting. The BMD and BV in the experimental group at 4 weeks after surgery was significantly higher than those in the control group (P<0.05). Conclusion: 4-hexylresorcinol and hydroxyapatite combination graft material showed higher initial bone formation than the control, however, there was no difference at 8weeks after operation.

An Efficient SLC Transition Method for Improving Defect Rate and Longer Lifetime on Flash Memory (플래시 메모리 상에서 불량률 개선 및 수명 연장을 위한 효율적인 단일 비트 셀 전환 기법)

  • Hyun-Seob Lee
    • Journal of Internet of Things and Convergence
    • /
    • v.9 no.3
    • /
    • pp.81-86
    • /
    • 2023
  • SSD (solid state disk), which is flash memory-based storage device, has the advantages of high density and fast data processing. Therefore, it is being utilized as a storage device for high-capacity data storage systems that manage rapidly increasing big data. However, flash memory, a storage media, has a physical limitation that when the write/erase operation is repeated more than a certain number of times, the cells are worn out and can no longer be used. In this paper, we propose a method for converting defective multi-bit cells into single-bit cells to reduce the defect rate of flash memory and extend its lifetime. The proposed idea distinguishes the defects and treatment methods of multi-bit cells and single-bit cells, which have different physical characteristics but are treated as the same defect, and converts the expected defective multi-bit cells into single-bit cells to improve the defect rate and extend the overall lifetime. Finally, we demonstrate the effectiveness of our proposed idea by measuring the increased lifetime of SSD through simulations.

The effect of deep level defects in SiC on the electrical characteristics of Schottky barrier diode structures (깊은 준위 결함에 의한 SiC SBD 전기적 특성에 대한 영향 분석)

  • Lee, Geon-Hee;Byun, Dong-Wook;Shin, Myeong-Cheol;Koo, Sang-Mo
    • Journal of IKEEE
    • /
    • v.26 no.1
    • /
    • pp.50-55
    • /
    • 2022
  • SiC is a power semiconductor with a wide bandgap, high insulation failure strength, and thermal conductivity, but many deep-level defects. Defects that appear in SiC can be divided into two categories, defects that appear in physical properties and interface traps that appear at interfaces. In this paper, Z1/2 trap concentration 0 ~ 9×1014 cm-3 reported at room temperature (300 K) is applied to SiC substrates and epi layer to investigate turn-on characteristics. As the trap concentration increased, the current density, Shockley-read-Hall (SRH), and Auger recombination decreased, and Ron increased by about 550% from 0.004 to 0.022 mohm.

Progess in Fabrication Technologies of Polycrystalline Silicon Thin Film Transistors at Low Temperatures

  • Sameshima, T.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2004.08a
    • /
    • pp.129-134
    • /
    • 2004
  • The development of fabrication processes of polycrystalline-silicon-thin-film transistors (poly-Si TFTs) at low temperatures is reviewed. Rapid crystallization through laser-induced melt-regrowth has an advantage of formation of crystalline silicon films at a low thermal budget. Solid phase crystallization techniques have also been improved for low temperature processing. Passivation of $SiO_2$/Si interface and grain boundaries is important to achieve high carrier transport properties. Oxygen plasma and $H_2O$ vapor heat treatments are proposed for effective reduction of the density of defect states. TFTs with high performance is reported.

  • PDF

Effect of Metal Oxide of Ceramic Superconductor for Neutron beam Irradiation (중성자 조사용 전기도체의 첨가물 효과)

  • Lee, Sang-Heon;Choi, Yong
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.57 no.3
    • /
    • pp.429-432
    • /
    • 2008
  • Much studies have been concentrated to develop the fabrication technique for high critical current density but still there are a lot of gap which should be overcome for large scale application of superconducting materials at liquid nitrogen temperature. The improvement of the critical current can be achieved by forming the nano size defect working as a flux pinning center inside the superconductor. In this paper, the establishment of fabrication condition and additive effects of second elements were examined so as to improve the related properties to the practical use of superconductor.

Activation for Boron Doped poly-Si films by Hydrogen doping

  • Yang, Joon-Young;Yu, S.H.;Oh, K.M.;Kim, J.I.;Yang, M.S.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2002.08a
    • /
    • pp.171-174
    • /
    • 2002
  • When boron ions are doped into the poly-Si films, the hydrogen ions doped with boron ions compensate the defect sites and suppress to produce damage density. These samples can be easily activated by hydrogen doping at high acceleration voltage($V_{acc}$).

  • PDF