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Mobile ad hoc networks use the wireless network and have wider applications especially in emergency situation, military combat zones, and the mobility vehicles. The mobile ad hoc network especially poses the problem of security and efficiency as the network is often subject to internal and external attacks. To overcome such problems, different protocols are proposed. In this study, an improved protocol is proposed which makes use of hexacol cluster method and thus provide greater efficiency and security to the network. For validating the proposed method, a stimulation was performed and results were compared with other protocols. The results indicate that the proposed method showed improved performance compare to the other protocol.

This article proposes new historical perspectives arising from the findings in the Sungai Batu Archaeological Complex, Kedah, by the Centre for Global Archaeological Research, Universiti Sains Malaysia in 2009. Excavations in the complex unearthed the remains of iron smelting sites, wharves and other brick structures, dating back to the 2nd/3rd century AD. The discoveries of furnaces, tuyeres and iron slag attest to Sungai Batu's role as the centre for primary iron production, employing the bloomery method. The study suggests that Ancient Kedah appeared as one of the hubs for the trans-Asiatic trade network with the rise of the iron industry, while its economic complexity grew steadily in successive centuries. The early emergence of Ancient Kedah was a development synchronous with the later phase of the Indian-Southeast Asian exchange network between the 2nd to the 4th century AD when inter and intra-regional trade intensified. Due to its favourable geological features, strategic location with a suitable ecozone, as well as being a thriving centre for primary iron production, Ancient Kedah emerged as an important harbour. It was this trading and industrial past, the article will argue, that contributed to the rise of other economic hubs within Ancient Kedah, such as Pengkalan Bujang and Kampung Sungai Mas, which eventually developed into entrepôts after the 5th century AD.

Suna Zhou,1,* Yaoyou Cui,1,* Dequan Yu,1 Jun Liang,1 Mingxin Zhang,2 Wenguang Ye2 1Department of Radiotherapy, 2Department of Gastroenterology, Tangdu Hospital, Fourth Military Medical University, Xi'an, China *These authors contributed equally to this work Background: Increasing evidence indicates that radioresistance remains a major problem in the treatment of patients with esophageal squamous cell carcinoma (ESCC). This study was designed to investigate the expression of microRNA-381 (miR-381) and its function in the radioresistance of ESCC.Methods: In this study, miR-381 expression was first detected in ESCC cell lines and tissue samples by quantitative real-time polymerase chain reaction (qRT-PCR). Then, the effects of miR-381 expression on growth, apoptosis, and radiosensitivity of ESCC cells were analyzed by MTT, colony formation, and flow cytometry, respectively. Dual-luciferase reporter assays were performed to validate the regulation of a putative target of miR-381, in corroboration with qRT-PCR and Western blotting assays.Results: ESCC cell lines or tissues were found to express significantly lower miR-381 than normal esophageal epithelial cells or adjacent normal tissues, respectively. Ectopic expression of miR-381 in ESCC cell lines blocked proliferation, reduced colony formation, enhanced apoptosis, and increased radiosensitivity by enhancing irradiation-induced apoptosis. In addition, dual-luciferase reporter assays showed that miR-381 binds to the 3'-untranslated region of X-linked inhibitor of apoptosis protein (XIAP), suggesting that XIAP should be a direct target of miR-381. Re-expression of miR-381 suppressed XIAP protein expression in ESCC cells, and the effects of miR-381 upregulation on ESCC cells were found to be similar with silencing of XIAP. In addition, XIAP mRNA expression significantly increased in ESCC tissues and was inversely correlated with miR-381 expression.Conclusion: The results of this study suggest that miR-381/XIAP pathway contributed to the growth inhibition, increase in apoptosis, and enhancement of radiosensitivity in ESCC cells Therefore, miR-381 may be a potential therapeutic target in human ESCC. Keywords: miR-381, esophageal squamous cell carcinoma, XIAP, growth, apoptosis