Antibacterial Activities of Actinomycete Isolates Collected from Soils of Rajshahi, Bangladesh

This study was performed to isolate actinomycete colonies having antibacterial activity from soil samples collected from different places around Rajshahi, Bangladesh. Thirty actinomycete colonies were isolated in pure culture from five soil samples using Starch-casein-nitrate-agar medium. The isolates were grouped in five color series based on their aerial mycelia color and screened for their antibacterial activity against a range of test bacteria. Sixteen isolates (53.3%) were found to have moderate to high activity against four gram-positive and four gram-negative bacteria. Since many isolates showed inhibitory activity against indicator bacteria, it is suggestive that Bangladeshi soil could be an interesting source to explore for antibacterial secondary metabolites

Water-soluble Fraction of Abelmoschus esculentus L Interacts with Glucose and Metformin Hydrochloride and Alters Their Absorption Kinetics after Coadministration in Rats

This study was done to investigate the effects of water-soluble fraction (WSF) of the fruits of Abelmoschus esculentus L (okra/lady's fingers) on absorption of oral glucose as well as metformin from the gastrointestinal tract in the Long Evans rats. WSF of A. esculentus significantly (P < 0.05) reduced the absorption of glucose as studied in the 24 hrs fasting rats. The effect of WSF of A. esculentus on metformin absorption was studied in alloxan-induced diabetic rats. Significant differences (P < 0.05) were observed in the average blood glucose level from 2 to 24 hours after metformin therapy in presence (33.6 to 34.2 mmol/L) or absence (15.2 to 20.2 mmol/L) of oral WSF of A. esculentus. In both of the experiments, Na-carboxymethylcellulose (CMC) was used as positive control. The results of this study indicate that A. esculentus may improve glycemic control but should not be taken concurrently with metformin hydrochloride in controlling diabetes mellitus

Manifestation and mitigation of node misbehaviour in adhoc networks

Mobile adhoc network is signified as a boon for advance and future wireless communication system. Owing to its self-establishing network features and decentralization, the system can actually establish a wireless communication with vast range of connectivity with the other nodes. However, the system of MANET is also beheld with various technical impediments owing to its inherent dynamic topologies. Although there are abundant volume of research work, but very few have been able to effectively address the node misbehavior problems in MANET. The paper initially tries to draw a line between different types of nodes in MANETs based on their behavior characteristics, then reviews some of the significant contribution of the prior researches for addressing node misbehavior issues. A major emphasis is laid on is the researches which use game theory as a tool to study and address the misbehavior problems. The manuscript is developed considering some of the latest and standard evidences of past 5 years and finally discusses the open issues related to the problems

Offline OTP based solution for secure internet banking access

Numerous applications are available on the Internet for the exchange of personal information and money. All these applications need to authenticate the users to confirm their legitimacy. Currently, the most commonly employed credentials include static passwords. But people tend to behave carelessly in choosing their passwords to avoid the burden of memorizing complex passwords. Such frail password habits are a severe threat to the various services available online especially electronic banking or e-banking. For eradicating the necessity of creating and managing passwords, a variety of solutions are prevalent, the traditional ones being the usage of One- Time-Password (OTP) that refers to a single session/transaction password. However, a majority of the OTP-based security solutions fail to satisfy the usability or scalability requirements and are quite vulnerable owing to their reliance on multiple communication channels. In this study, the most reliable and adoptable solution which provides better security in online banking transactions is proposed. This is an initiative to eradicate the dependency on Global System for Mobile communication (GSM) that is the most popular means of sending the One- Time-Passwords to the users availing e-banking facilities

A survey on MANETs: architecture, evolution, applications, security issues and solutions

Mobile ad hoc networks or MANETs, also referred to as mobile mesh networks at times, are self-configuring networks of mobile devices that are joined using wireless channels. These represent convoluted distributed systems comprising of wireless mobile nodes which are free to move and self-organise dynamically into temporary and arbitrary, ad hoc topologies. This makes it possible for devices as well as people to internetwork seamlessly in such regions that have no communication infrastructure in place. Conventionally, the single communication networking application following the ad hoc concept had been tactical networks. Lately, new technologies have been introduced such as IEEE 802.11, Hyperlan and Bluetooth that are assisting in the deployment of commercial MANETs external to the military realm. Such topical evolutions infuse a new and rising interest in MANET research and development. This paper provides an overview of the dynamic domain of MANETs. It begins with the discussion on the evolution of MANETs followed by its significance in various fields. Besides, the MANETs have been analysed from the security perspective, particularly the work performed in the node misbehaviour paradigm has been elaborated

Effectiveness of integrated weed management in five varieties of aromatic rice in Bangladesh

An experiment was carried out at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh, Bangladesh to evaluate the efficacy, rice selectivity and cost-effectiveness of some integrated weed control methods on the productivity of aromatic rice under randomized complete block design with three replications. The experiment consisted of five aromatic rice varieties; Kalijira, BRRI dhan34, BRRI dhan37, BRRI dhan38 and Binadhan-13, and six different weed management practices comprising no weeding, weed free, mechanical + manual weeding, pre–emergence herbicide + manual weeding, post–emergence herbicide + manual weeding, pre– + post–emergence herbicide. Ten weed species belonging to five families infested the experimental plots. Herbicide treatments provided excellent weed control efficiency and produced much higher net benefit and cost benefit ratio than weedy plot. Among the herbicidal and mechanical treatments, sequential application of Bensulfuran methyl + Acetachlor at early growth stage (pre-emergence herbicide) followed by Pyrazosulfuran ethyl at mid growth stage (post-emergence herbicide) provided the highest weed control efficiency, productivity and net benefit. Single application of Pyrazosulfuran ethyl at mid growth stage followed by one hand weeding performed very close to the pre– + post–emergence herbicide application in terms of productivity and net benefit but in terms of weed control efficiency at 45 days after transplanting application of Bensulfuran methyl + Acetachlor at early growth stage followed by one hand weeding performed very close to pre– + post–emergence herbicide application. Mechanical weeding followed by one hand weeding and application of Bensulfuran methyl + Acetachlor at early growth stage followed by one hand weeding also provided satisfactory results in terms of productivity and economic return. Since manual weeding was less economic, sequential application of pre- and post-emergence herbicides may be recommended for effective weed management in aromatic rice

Game theory for resource allocation in heterogeneous wireless networks - a review

In next-generation wireless networks, a user can be connected through MultiMode Device (MMD) to the multiple wireless networks in Heterogeneous Wireless Networks (HWN) considering several factors; including network technology, data service type, available bandwidth, Quality of Service (QoS), monetary cost, etc. To deal with all these multi attributes, game theory based models have been used to point out a better solution. This paper evaluates the techniques, methods, advantages, limitations of some game theory-based models for wireless resource allocation in HWN. Finally, it concludes that the Shapley Value method can be used for further research activities for its efficiency

A novel multi-agent and multilayered game formulation for Intrusion Detection in Internet of Things (IoT)

The current era of smart computing and enabling technologies encompasses the Internet of Things (IoT) as a network of connected, intelligent objects where objects range from sensors to smartphones and wearables. Here, nodes or objects cooperate during communication scenarios to accomplish effective throughput performance. Despite the deployment of large-scale infrastructure-based communications with faster access technologies, IoT communication layers can still be affected with security vulnerabilities if nodes/objects do not cooperate and intend to take advantage of other nodes for fulfilling their malevolent interest. Therefore, it is essential to formulate an intrusion detection/prevention system that can effectively identify the malicious node and restrict it from further communication activities—thus, the throughput, and energy performance can be maximized to a significant extent. This study introduces a combined multi-agent and multilayered game formulation where it incorporates a trust model to assess each node/object, which is participating in IoT communications from a security perspective. The experimental test scenarios are numerically evaluated, where it is observed that the proposed approach attains significantly improves intrusion detection accuracy, delay, and throughput performance as compared to the existing baseline approaches