North Eastern Regional Institute of Science and Technology

About: North Eastern Regional Institute of Science and Technology is a education organization based out in Itanagar, India. It is known for research contribution in the topics: Population & Raman spectroscopy. The organization has 813 authors who have published 1429 publications receiving 16122 citations.

Antimicrobial Potential of Carvacrol against Uropathogenic Escherichia coli via Membrane Disruption, Depolarization, and Reactive Oxygen Species Generation.

Abstract: Bacterial resistance to antibiotics poses a serious threat to cure diseases associated with microbial infection. Among the resistant bacteria, extended-spectrum β-lactamase (ESBL)-producing bacteria are the most concerned one as they encode the enzyme β-lactamase that confers resistance to most β-lactam antibiotics. The present study was carried out to determine the antimicrobial potential and the principle mechanism of action of carvacrol against ESBL Escherichia coli isolated from ascitic fluid of a patient having a urinary tract infection. Carvacrol exhibited a minimum inhibitory concentration (MIC) of 450 μg/ml at which it reduced E. coli cell counts significantly in a time-dependent manner. Carvacrol completely diminished the growth of E. coli after 2 h of incubation at its MIC. Fluorescent imaging displayed the elevated reactive oxygen species level and bacterial membrane depolarization leading to E. coli cell death in presence of carvacrol at its MIC. Furthermore, carvacrol displayed a severe detrimental effect on bacterial membrane disruption and cellular material release. In addition, a significant effect of carvacrol at sub-inhibitory concentration was observed on motility of E. coli cells and invasion of human colon HCT-116 cells in an ex vivo model. Based on the results, we conclude a potential antimicrobial role of carvacrol against ESBL E. coli.

Collaborative techniques for intrusion detection in mobile ad-hoc networks

Abstract: In this paper, we present two intrusion detection techniques for mobile ad-hoc networks, which use collaborative efforts of nodes in a neighborhood to detect a malicious node in that neighborhood. The first technique is designed for detection of malicious nodes in a neighborhood of nodes in which each pair of nodes in the neighborhood are within radio range of each other. Such a neighborhood of nodes is known as a clique[12]. The second technique is designed for detection of malicious nodes in a neighborhood of nodes, in which each pair of nodes may not be in radio range of each other but where there is a node among them which has all the other nodes in its one-hop vicinity. This neighborhood is identical to a cluster as mentioned in [12]. Both techniques use message passing between the nodes. A node called the monitor node initiates the detection process. Based on the messages that it receives during the detection process, each node determines the nodes it suspects to be malicious and send votes to the monitor node. The monitor node upon inspecting the votes determines the malicious nodes from among the suspected nodes. Our intrusion detection system is independent of any routing protocol. We give the proof of correctness of the first algorithm, which shows that it correctly detects the malicious nodes always when there is no message loss. We also show with the help of simulations that both the algorithms give good performance even when there are message losses arising due to unreliable channel.