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1	Effects of isolation methods on proliferation and GD2 expression by porcine umbilical cords stem cells Walker, Kristen Elizabeth January 1900 (has links) Master of Science / Department of Animal Sciences and Industry / Duane L. Davis / Cell isolation method may have effects on the characteristics of the cells isolated from porcine umbilical cords. As stem cells age or approach senescence, it is hypothesized that their properties change. We expect that isolation method and age of cells will have effects on the phenotype of porcine umbilical cord (PUC) cells during in vitro expansion. We investigated the effects of three isolation methods on PUC population doublings, ability to produce colony forming units (CFU), and amount of ganglioside GD2 (GD2) expression over eleven passages. Isolation methods were explant (Exp) in which the Wharton's Jelly was removed from cords, minced and plated, enzyme digest (Dig), and stomacher assisted enzyme digestion (Stom). Cell isolates were analyzed for GD2 expression, CFU, and population doublings at early (3), middle (7), and late (11) passage. The Exp method produced greater (P<0.05) population doublings and more (P<0.05) CFU at passage 7. Explant isolates also were numerically more likely to survive to passage 11 (9/9 isolates vs 5/9 for Dig and 7/9 for Stom). In contrast, the percent cells expressing GD2 was greater (P<0.05) for Stom isolates than Exp isolates at passage 11. There were no trends for increased passage number to decreased population doubling, CFU formation, or percent GD2 positive cells. In summary, our results indicate that the Exp isolation method produced the greatest number of population doublings over 11 passages and there were minimal effects of isolation method on CFU and GD2 expression. Although Exp may be more difficult to scale up to isolate all of the PUCs in a cord, it provided greater in vitro expansion than the enzyme methods in our experiment and may provide the most cells for biotechnological and biomedical applications. GD2 Wharton's Jelly PUCs Explant Enzyme digest Biology, Cell (0379)
2	Changing from the silo model to the horizontal layers model in public policy regulations: the implications and potential for the telecommunications industry Spencer Logan, Lemuella C. 12 1900 (has links) The end of the Twentieth Century and the start of the Twenty First Century has been a tumultuous time for the Telecommunications Industry. Even as it moves forward to embrace the new technologies the Industry finds itself embroiled in issues of governance. The Industry finds itself in a dilemma since innovations increase at a rate faster than the laws can be changed and these render its existing laws and policies to be in some cases obsolete and inappropriate for the reality of the present. In the past, the United States of America has relied on vertically integrated top down laws and methods of regulating all the different parts in its Telecommunications Industry. These laws are contained in the different numbered Titles of this Countrys Legal Codes. Since the inception of these laws, emphasis was placed in creating and documenting policies structured by industry, sector and type of content. This form of regulation is usually referred to as the Silo Method. However, in recent years, especially in the regulation of the Telephony industry, the method of law and rule formulation moved from content regulation to one in which the technologies are getting regulated in what has been described as a Layers Method. This paper first considered whether the Silo Method of regulation is in actuality the same as using the Horizontal Layers method and showed that this is the case. Then it determined that Enhanced Services are the same as Basic Services and that Telecommunications Services are the same as Information services and showed that given that the pair sets as noted were the same, it went on to conclude that all these services were essentially the same. While studying to some detail the technologies of VoIP, the paper also showed that VoIP although an Internet technology is similar to traditional telephony, and is both a Telecommunications Service and Information Service based on the definition as given in the law as well as the technologies that are used and that as a result of this, the current regulatory environment for this service with regards to telephony is inconsistent. It concluded that Telecommunications policies though now adequate may need to be modified. Telecommunication/Internet Issues Telecommunications regulations Cable networks Cellular networks Common carriers Competitive carriers Computer inquiries Convergence Deregulation Digital networks FCC Federal Communications Commission Fiber optics Gatekeepers Gateways H.323 Horizontal Layers Model ICANN ILECs Information services Intelligent Network Architecture ISDN LAN LECs Loops LRN Call Flow MAN Network speed Networks NTIA OSI Model OSS Packet networks Packet switches Policies Protocols PSTN Networks PUCs Regulation SIP Spam SPY ACT Switched networks TC/IP Protocol Telecommunications Act of 1996 Telecommunications regulations Unbundled access UNCTAD UNICITRAL Vertical Silo Model VoIP VPN WAN Wireless Telecommunication Law and legislation Telecommunication Law and legislation

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Effects of isolation methods on proliferation and GD2 expression by porcine umbilical cords stem cells

Changing from the silo model to the horizontal layers model in public policy regulations: the implications and potential for the telecommunications industry