The Experts below are selected from a list of 696450 Experts worldwide ranked by ideXlab platform
David Amiel - One of the best experts on this subject based on the ideXlab platform.
-
Articular cartilage repair using allogeneic perichondrocyteseeded biodegradable porous polylactic acid (PLA): A tissue‐Engineering Study
Journal of Biomedical Materials Research, 1995Co-Authors: Richard D. Coutts, Makoto Yoshioka, Frederick L. Harwood, Anna Z. Monosov, David AmielAbstract:Efforts to expand treatment options for articular cartilage repair have increasingly focused on the implantation of cell-polymer constructs. The purpose of this Study is to determine the suitability of porous D,D-L,L-polylactic acid as a carrier for delivering repair cells obtained from rib perichondrium into full-thickness articular cartilage defects. In vitro characterization of perichondrocyte-polylactic acid composite grafts was combined with in vivo assessment of the early articular cartilage repair in a clinically relevant model. Using a fluorescent double-stain protocol to visualize live and dead cells in situ, primary cells cultured from perichondrium were found to be capable of attaching to and surviving within a porous D,D-L,L-polylactic acid matrix. These perichondrocyte-polylactic acid composite grafts were then implanted within osteochondral defects drilled into the left medial femoral condyles of 16 adult New Zealand white rabbits. Experimental animals were sacrificed 6 weeks after implantation and the repair tissue was evaluated grossly, histologically, and biochemically. Grossly, 96% (15/16) of the experimental animals demonstrated repairs consisting of a smooth, firm neocartilage which appeared similar in color and texture to the surrounding articular surface. Matrix staining for cartilaginous protein was seen surrounding chondrocyte-like cells in the cartilage regions of the repair. Cellular alignment was found to be related to scaffold architecture. These results suggest that scaffolds composed of porous D,D-L,L-polylactic acid support the growth of cartilaginous repair tissue and are compatible with both in vitro and in vivo survival of chondrogenic cells.
Selim Senkan - One of the best experts on this subject based on the ideXlab platform.
-
Oxidative coupling of methane with La2O3–CeO2 nanofiber fabrics: A reaction Engineering Study
Journal of Natural Gas Science and Engineering, 2014Co-Authors: Daniel Noon, Bahman Zohour, Selim SenkanAbstract:Abstract The effects of changes in various operating conditions were explored on the performance of an oxidative coupling of methane (OCM) reaction using La 2 O 3 –CeO 2 nanofiber fabric catalysts in a packed bed reactor. The operating conditions were: 1 atm pressure, CH 4 /O 2 ratio 4–7, feed flow rate 80–320 sccm, catalyst loading 5–20 mg, feed gas temperature 300–620 °C. These studies revealed that the rates of the OCM reaction is largely dominated by mass transfer limitations as evidenced by increases in reactor bed temperatures with increasing feed flow rates. C 2+ selectivities and yields of up to 70% and 18% respectively were also attained. Experiments with different catalyst loadings indicated that short catalytic beds are preferred for increasing C 2+ selectivities in OCM reactors.
-
oxidative coupling of methane with la2o3 ceo2 nanofiber fabrics a reaction Engineering Study
Journal of Natural Gas Science and Engineering, 2014Co-Authors: Daniel Noon, Bahman Zohour, Selim SenkanAbstract:Abstract The effects of changes in various operating conditions were explored on the performance of an oxidative coupling of methane (OCM) reaction using La 2 O 3 –CeO 2 nanofiber fabric catalysts in a packed bed reactor. The operating conditions were: 1 atm pressure, CH 4 /O 2 ratio 4–7, feed flow rate 80–320 sccm, catalyst loading 5–20 mg, feed gas temperature 300–620 °C. These studies revealed that the rates of the OCM reaction is largely dominated by mass transfer limitations as evidenced by increases in reactor bed temperatures with increasing feed flow rates. C 2+ selectivities and yields of up to 70% and 18% respectively were also attained. Experiments with different catalyst loadings indicated that short catalytic beds are preferred for increasing C 2+ selectivities in OCM reactors.
Aad Van Moorsel - One of the best experts on this subject based on the ideXlab platform.
-
designed to be broken a reverse Engineering Study of the 3d secure 2 0 payment protocol
Financial Cryptography, 2019Co-Authors: Mohammed Aamir Ali, Aad Van MoorselAbstract:3 Domain Secure 2.0 (3DS 2.0) is the most prominent user authentication protocol for credit card based online payment. 3DS 2.0 relies on risk assessment to decide whether to challenge the payment initiator for second factor authentication information (e.g., through a passcode). The 3DS 2.0 standard itself does not specify how to implement transaction risk assessment. The research questions addressed in this paper therefore are: how is transaction risk assessment implemented for current credit cards and are there practical exploits against the 3DS 2.0 risk assessment approach? We conduct a detailed reverse Engineering Study of 3DS 2.0 for payment using a browser, the first Study of this kind. Through experiments with different cards, from different countries and for varying amounts, we deduct the data and decision making process that card issuers use in transaction risk assessment. We will see that card issuers differ considerable in terms of their risk appetite. We also demonstrate a practical impersonation attack against 3DS 2.0 that avoids being challenged for second factor authentication information, requiring no more data than obtained with the reverse Engineering approach presented in this paper.
Richard D. Coutts - One of the best experts on this subject based on the ideXlab platform.
-
Articular cartilage repair using allogeneic perichondrocyteseeded biodegradable porous polylactic acid (PLA): A tissue‐Engineering Study
Journal of Biomedical Materials Research, 1995Co-Authors: Richard D. Coutts, Makoto Yoshioka, Frederick L. Harwood, Anna Z. Monosov, David AmielAbstract:Efforts to expand treatment options for articular cartilage repair have increasingly focused on the implantation of cell-polymer constructs. The purpose of this Study is to determine the suitability of porous D,D-L,L-polylactic acid as a carrier for delivering repair cells obtained from rib perichondrium into full-thickness articular cartilage defects. In vitro characterization of perichondrocyte-polylactic acid composite grafts was combined with in vivo assessment of the early articular cartilage repair in a clinically relevant model. Using a fluorescent double-stain protocol to visualize live and dead cells in situ, primary cells cultured from perichondrium were found to be capable of attaching to and surviving within a porous D,D-L,L-polylactic acid matrix. These perichondrocyte-polylactic acid composite grafts were then implanted within osteochondral defects drilled into the left medial femoral condyles of 16 adult New Zealand white rabbits. Experimental animals were sacrificed 6 weeks after implantation and the repair tissue was evaluated grossly, histologically, and biochemically. Grossly, 96% (15/16) of the experimental animals demonstrated repairs consisting of a smooth, firm neocartilage which appeared similar in color and texture to the surrounding articular surface. Matrix staining for cartilaginous protein was seen surrounding chondrocyte-like cells in the cartilage regions of the repair. Cellular alignment was found to be related to scaffold architecture. These results suggest that scaffolds composed of porous D,D-L,L-polylactic acid support the growth of cartilaginous repair tissue and are compatible with both in vitro and in vivo survival of chondrogenic cells.
B.a. Williams - One of the best experts on this subject based on the ideXlab platform.
-
TWRS privatization phase 1 monitoring wells Engineering Study
1998Co-Authors: B.a. Williams, D.r. NewcomerAbstract:This Engineering Study provides an evaluation of existing wells and boreholes (wells) within the proposed location for the Tank Waste Remediation System (TWRS) Privatization Phase 1 demonstration site. Phase 1 is part of the TWRS program that was established to manage, retrieve, treat, immobilize, and dispose of high-level waste stored in underground tanks at the Hanford Site. This evaluation is to determine which wells will remain active within the demonstration site based on regulatory, programmatic, or other beneficial use requirements. An initial evaluation of wells within the demonstration site was conducted in 1996. However, changes in construction plans and expansion of the demonstration site necessitated a reevaluation and reclassification of the wells that are within the expanded site. Impacted wells include many of those previously evaluated as well as additional wells identified in or near the expansion areas. Thirty-three wells exist within and immediately adjacent to the identified boundary of the proposed demonstration site. The wells identified for decommissioning will be abandoned according to the well decommissioning plan. Future well requirements within the site include replacement wells for those wells impacted by construction activities, replacements for Resource Conservation and Recovery Act of 1976 (RCRA) wells going dry, and a new characterization well installed to support a TWRS Phase 2 site assessment.
-
TWRS privatization: Phase I monitoring well Engineering Study and decommissioning plan
1996Co-Authors: B.a. WilliamsAbstract:This Engineering Study evaluates all well owners and users, the status or intended use of each well, regulatory programs, and any future well needs or special purpose use for wells within the TWRS Privatization Phase I demonstration area. Based on the evaluation, the Study recommends retaining 11 of the 21 total wells within the demonstration area and decommissioning four wells prior to construction activities per the Well Decommissioning Plan (WHC-SD-EN-AP-161, Rev. 0, Appendix I). Six wells were previously decommissioned.