Pyrazole-based analogs as potential antibacterial agents against methicillin-resistance staphylococcus aureus (MRSA) and its SAR elucidation

Methicillin-resistant Staphylococcus aureus (MRSA) is becoming lethal to humanity due to easy transmission and difficult-to-treat skin and flimsy diseases. The most threatening aspect is the rapid resistance development of MRSA to any approved antibiotics, including vancomycin. The development of new, efficient, and nontoxic drug candidate to fight against MRSA isolates is the need of the hour. The intriguing molecular structure and versatile bioactive pyrazole core attracting to development required novel antibiotics. This review presents the decade developments of pyrazole-containing derivatives with a broad antibacterial movement against diverged bacterial strains. In specific, we correlated the efficacy of structurally diversified pyrazole analogs against MRSA and discussed different angles of structure-activity relationship (SAR). The current survey highlights pyrazole hybrids' present scenario on MRSA studies, covering articles published from 2011 to 2020. This collective information may become an excellent platform to plan and develop new pyrazole-based small MRSA growth inhibitors with minimal side effects. (C) 2020 Elsevier Masson SAS. All rights reserved

Analisis Perbandingan Performansi Fast Handover pada Proxy Mobile IPv6 (FPMIPv6) dan Hierarchical Mobile IPv6 (FHMIPv6) menggunakan IEEE 802.21 Media Independent Handover Function pada Heterogeneous Network

ABSTRAKSI: Mobile IP adalah protokol internet yang mendukung mobilitas dari host, sehingga setiap host berpindah access point tidak perlu ganti IP, namun masalah yang ada yaitu handover latency dan packet loss akibat proses handover. Dalam Mobile IP ada 2 macam pendekatan untuk penanganan mobilitas, yaitu host-based mobility dan network-based mobility. Pada host-based dibutuhkan keterlibatan mobile node untuk komunikasi dengan home agent melalui network node. Lain halnya dengan network-based, mobile node tidak ikut terlibat dalam proses komunikasi dengan home agent, cukup network node saja yang bertugas mengaturnya. Kondisi jaringan yang ada saat ini ada beberapa lingkungan coverage network seperti WLAN, WiMAX, 3G, LTE. IEEE mengeluarkan standar 802.21 Media Independent Handover Function, pengaturan untuk vertical handover.Pada tugas akhir ini dilakukan simulasi untuk mengetahui pengaruh handover pada performansi Proxy Mobile IPv6 dengan Hierarchical Mobile IPv6 menggunakan 802.21 MIH pada lingkungan jaringan 802.11 dan 802.16 di domain lokal. Parameter yang dianalisa adalah handover latency, packet loss, throughput, dan delay. Pada domain lokal, Proxy Mobile IP memiliki nilai handover latency, packet loss, dan throughput 20% lebih baik dibandingkan dengan Hierarchical Mobile IP. KATA KUNCI: Mobile IPv6, Fast handover, PMIPv6, HMIPv6, mobility management, heterogeneous network, MIHABSTRACT: Mobile IP is an Internet protocol that supports mobility of hosts, so that each host move and change it\u27s access point does not need to change the IP, but the problem is the handover latency and packet loss due to handover process. In Mobile IP there are two kinds of approaches to the handling of mobility, which is host-based and network-based mobility mobility. In host-based mobile node involvement is needed for communication with the home agent via the network nodes. As with the network-based, mobile nodes are not involved in the process of communication with the home agent, sufficient network nodes are tasked to set it. Network conditions that exist at this time there is some coverage of network environments such as WLAN, WiMAX, 3G, LTE. Standard IEEE 802.21 Media Independent Handover Function had been published for arrangements in vertical handover.In this final simulation conducted to determine the effect of handover on the performance of Proxy Mobile IPv6 with Hierarchical Mobile IPv6 using MIH 802.21 at 802.11 and 802.16 network environment. The parameters analyzed were handover latency, packet loss, throughput, and delay. In the local domain, Proxy Mobile IP has a 20% better value for handover latency, packet loss, throughput compared to Hierarchical Mobile IP.KEYWORD: Mobile IPv6, Fast handover, PMIPv6, HMIPv6, mobility management, heterogeneous network, MI

Proposta e Estudo de Soluções para Otimização de Rotas em Ambientes de Mobilidade de Redes

Tese de doutoramento em Engenharia Informática, apresentada à Faculdade de Ciências e Tecnologia da Universidade de CoimbraNo mundo de hoje, no qual se acentua a tendência para que todo o tipo de comunicações recorra à arquitetura TCP/IP e crescem, em número e tipo, os dispositivos que utilizam ligações sem fios, a mobilidade em ambiente IP assume um papel de extrema importância. Por esse facto, tem sido grande a atenção da comunidade científica à proposta e desenvolvimento de soluções de mobilidade IP de nós individuais e de redes. O NEMO Basic Support Protocol, IETF RFC 3963, foi desenvolvido com o objetivo de fornecer mobilidade de redes de forma imediata e transparente para a Internet atual. Contudo, a sua simplicidade está na génese das suas maiores limitações, que resultam em claros problemas de desempenho. Por outro lado, nenhuma das alternativas propostas com o intuito de resolver estas limitações conseguiu reunir consenso. Nesta tese é apresentada uma mudança de paradigma, que consiste em envolver os dispositivos finais nos processos de mobilidade de redes. A proposta Optimised Mobility for Enhanced Networking, OMEN, faculta os mecanismos necessários para que os dispositivos finais tomem consciência da sua condição de mobilidade e possam recorrer aos mecanismos de otimização de rotas já previstos no MIPv6, de forma a não estarem sujeitos às limitações do RFC 3963. Com esta medida consegue-se resolver o problema da decisão da altura ideal para otimizar a rota de um determinado fluxo e, ao mesmo tempo, permitir que os elementos da infraestrutura de rede móvel fiquem dedicados às suas funções de encaminhamento de pacotes, resultando num incremento acentuado do desempenho da rede e num decréscimo do consumo de energia. As simulações realizadas mostram que a proposta OMEN apresenta valores de desempenho de comunicação e de perda de pacotes substancialmente melhores que as restantes soluções existentes, corroborando as vantagens da mudança de paradigma. Para a realização dos diversos estudos de comparação das soluções foi necessário desenvolver um emulador que permitisse resolver as limitações de falta de implementação das soluções de mobilidade de redes e, ao mesmo tempo, permitir simulações de larga escala e de carga na rede. O emulador desenvolvido, denominado mobSim, foi executado num cluster de grandes dimensões, dado o tamanho e complexidade dos cenários de simulação.In the current world, in which there is a growing trend to use the TCP/IP protocol suite in all types of communication networks, and the number and type of devices using wireless connections is growing, IP mobility of both nodes and networks is of extreme importance. This is the main reason why the scientific community has paid and is paying special attention to the proposal and development of IP mobility solutions. The NEMO Basic Support Protocol, IETF RFC 3963, was developed with the objective of readily allowing transparent network mobility in the current Internet. Nevertheless, the simplicity of this solution is at the basis of its limitations, which severely affect its performance. On the other hand, none of the proposed alternatives is gathering enough consensus of the community. In this thesis, a paradigm shift is proposed, consisting of involving end nodes in the network mobility process. The proposal, named Optimised Mobility for Enhanced Networking, OMEN, establishes the necessary means for informing end nodes of their mobility condition, which can then use existing MIPv6 route optimisation mechanisms in order for them not to be subject to the limitations of RFC 3963. In this way, the problem of deciding which and when to optimise flows is left to the end nodes, which are in the best position to decide. At the same time, mobile routers are freed from all tasks concerning the mobility management of a potentially large number of flows, making them lighter and with lower power requirements. The performed simulations show that the OMEN proposal leads to better performance then existing network mobility solutions, confirming the advantages of the paradigm shift. The performed studies were carried out using a specially built network mobility emulator, in order to overcome the lack of support for this type of mobility and the scalability limitations of existing simulators. The developed emulator, named mobSim, ran in a large cluster, due to the size and complexity of the simulated scenarios.IST-FP6-0384239: CONTENT – Network of Excellence on Content Networks and Services for Home UsersFCT PTDC/EIA –EIA/116173/2009: CoFiMoM - Combate a Incêndios com Multihoming e Mobilidad