Investigating the Impact of Mobility Models on MANET Routing Protocols
INTERNATIONAL JOURNAL OF ADVANCED COMPUTER SCIENCE AND APPLICATIONS
Authors: Abdullah, Ako Muhammad; Ozen, Emre; Bayramoglu, Husnu
Abstract
A mobile ad hoc network (MANET) is a type of multi-hop network under different movement patterns without requiring any fixed infrastructure or centralized control. The mobile nodes in this network moves arbitrarily and topology changes frequently. In MANET routing, protocols play an important role to make reliable communication between nodes. There are several issues affecting the performance of MANET routing protocols. Mobility is one of the most significant factors that have an impact on the routing process. In this paper, FCM, SCM, RWM and HWM mobility models are designed to analyze the performance of AODV, OLSR and GRP protocols, with ten pause time values. These models are based on varying speeds and pause time of MANET participants. Different node parameters such as data drop rate, average end-to-end delay, media access delay, network load, retransmission attempts and throughput are used to make a performance comparison between mobility models. The simulation results showed that in most of the cases OLSR protocol provides better performance than other two routing protocols and it is more suitable for networks that require low delay and retransmission attempts, and high throughput.
Development of an orthotopic canine prostate cancer model expressing human GRPr
PROSTATE
Authors: Tweedle, Michael F.; Ding, Haiming; Drost, William T.; Dowell, Joshua; Spain, James; Joseph, Mathew; Elshafae, Said M.; Menendez, Maria-Isabela; Gong, Li; Kothandaraman, Shankaran; Dirksen, Wessel P.; Wright, Chadwick L.; Bahnson, Robert; Knopp, Michael V.; Rosol, Thomas J.
Abstract
BackgroundAce-1 canine prostate cancer cells grow orthotopically in cyclosporine immunosuppressed laboratory beagles. We previously transfected (human Gastrin-Releasing Peptide Receptor, huGRPr) into Ace-1 cells and demonstrated receptor-targeted NIRF imaging with IR800-G-Abz4-t-BBN, an agonist to huGRPr. Herein, we used the new cell line to develop the first canine prostate cancer model expressing a human growth factor receptor. MethodsDogs were immunosuppressed with cyclosporine, azathioprine, prednisolone, and methylprednisolone. Their prostate glands were implanted with Ace-1(huGRPr) cells. The implantation wounds were sealed with a cyanoacrylic adhesive to prevent extraprostatic tumor growth. Intraprostatic tumors grew in 4-5 week. A lobar prostatic artery was then catheterized via the carotid artery and 25-100nmol IR800-Abz4-t-BBN was infused in 2mL followed by euthanasia in dogs 1-2, and recovery for 24h before euthanasia in dogs 3-6. Excised tissues were imaged optically imaged, and histopathology performed. ResultsDog1 grew no tumors with cyclosporine alone. Using the four drug protocol, Dogs 2-6 grew abundant 1-2mm intracapsular and 1-2cm intraglandular tumors. Tumors grew >5cm when the prostate cancer cells became extracapsular. Dogs 4-6 with sealed prostatic capsule implantation sites had growth of intracapsular and intraglandular tumors and LN metastases at 5 weeks. High tumor to background BPH signal in the NIRF images of sectioned prostate glands resulted from the 100nmol dose (approximate to 8nmol/kg) in dogs 2-4 and 50nmol dose in dog 5, but not from the 25nmol dose in Dog 6. Imaging of mouse Ace-1(huGRPr) tumors required an intravenous dose of 500nmol/kg body wt. A lymph node that drained the prostate gland was detectable in Dog 4. Histologic findings confirmed the imaging data. ConclusionAce-1(huGRPr) cells created viable, huGRPr-expressing tumors when implanted orthotopically into immune-suppressed dogs. Local delivery of an imaging agent through the prostatic artery allowed a very low imaging dose, suggesting that therapeutic agents could be used safely for treatment of early localized intraglandular prostate cancer as adjuvant therapy for active surveillance or focal ablation therapies, or for treating multifocal intraglandular disease where focal ablation therapies are not indicated or ineffective.