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The flourish of P2P systems draws a lot of attention of networking researchers. Some research efforts focus on P2P systems, trying to understand the mechanism of various implementations and the behavior pattern of P2P users, and then improve the systems' performance. Others look at the issue from the angle of ISPs, trying to help ISPs solve various issues brought by P2P applications. In this article, we conduct a review study on recent research efforts in these two areas. The first part of this article focuses on several key strategies that have significant influence on the performance of P2P systems. In the second part, we review some important techniques for ISPs to manage P2P traffic, i.e., blocking, caching and localization, and compare their advantages and disadvantages.

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Leukemia represents a spectrum of hematological malignancies threatening human health. Resistance to treatments and metastasis of leukemia are the main causes of death in patients. Leukemia stem cells (LSCs) are the initiating cells of leukemia as well as the main source of drug resistance, invasion and metastasis. Consequently, eliminating LSCs is a prerequisite to eradicate leukemia. Preliminary studies in our laboratory have shown that chemokines and their related receptors play an important role in the drug resistance and metastasis of leukemic cells. In this study, we obtained high migration drug-surviving (short term) MOLT4 cells (hMDSCs-MOLT4) with treatment of doxorubicin (DOX) after Transwell assay. Then we detected stem cell-associated molecular markers on hMDSCs-MOLT4 cells and the parental MOLT4 cells by FCM, QPCR, western blotting, H&E staining and immunohisto-chemistry experimental techniques in vitro and in vivo. Moreover, we explored its impact on drug resistance and tumor formation. Then we found that compared with the parental MOLT4 cells, the mRNA expression levels of stem cell-related factors Sox2, Oct4, C-myc, Klf4, Nanog, Bmi-1, CXCR4 are increased in hMDSCs-MOLT4 cells, together with the protein expression levels of Sox2, Oct4, Klf4, Nanog, CXCR4 and CD34. Our results indicated that hMDSCs-MOLT4 cells exhibited strong drug resistance and certain cancer stem cell-like characteristics. It is the first indication that the targeting stemness factors such as Sox2, Oct4, Klf4, Nanog and CXCR4 may represent plausible options for eliminating T-ALL stem-like cells. The present findings shed light on the relationship between drug-tolerant leukemic cells and cancer stem cells.

As IPv6 has much larger address space than IPv4, investigating the characteristics of IPv6 prefixes is of great benefit to understand and manage IPv6 networks. In this paper, 1) we conduct a case study on prefix-level characteristics in IPv6 world. We find that the number of assigned prefixes and the coverage areas are increasing and expanding. Traffic and packet distribution across prefixes are highly skewed. The sizes of active prefixes are relatively stable over time. These results provide experimental basis for routing cache design in IPv6 world. If we update the routing cache once an hour, we only need to reserve 5184 bytes memory for the worst-case burst changes. 2) In addition, we find that 61% destination prefixes have more than two paths to reach, which shows that multihoming path diversity of the studied IPv6 network is obvious. Therefore, we propose an experimental framework with the ability of measuring the performance of each destination prefix, tuning the path for each destination prefix with the best performance, and evaluating the effect during and after the performance tuning. IPv6 has been experiencing fast development as the next generation network. Hence understanding prefix-level characteristics and enhancing performance management are essential for IPv6 networks.