Marcos Paulo Gomes Pinheiro

Feeding Preferences of Lutzomyia longipalpis (Diptera: Psychodidae), the Sand Fly Vector, for Leishmania infantum (Kinetoplastida: Trypanosomatidae)

ABSTRACT Leishmania infantum, the causative agent of visceral leishmaniasis (VL) in Brazil, is spread mostly by the bite of the sand fly Lutzomyia longipalpis (Lutz & Neiva). We trapped sand flies in endemic neighborhoods near Natal, Brazil, where cases of human and dog VL were documented. Amplification of species-specific cytochrome b (Cyt b) genes by polymerase chain reaction revealed that sand flies from rural and periurban areas harbored blood from different sources. The most common source of bloodmeal was human, but blood from dog, chicken, and armadillo was also present. We tested the preference for a source of bloodmeal experimentally by feeding L. longipalpis F1 with blood from different animals. There were significant differences between the proportion of flies engorged and number of eggs laid among flies fed on different sources, varying from 8.4 to 19 (P < 0.0001). Blood from guinea pig or horse was best to support sand fly oviposition, but human blood also supported sand fly oviposition well. No sand flies fed on cats, and sand flies feeding on the opossum Monodelphis domestica Wagner produced no eggs. These data support the hypothesis that L. longipalpis is an eclectic feeder, and humans are an important source of blood for this sand fly species in periurban areas of Brazil.

Ecological interactions among phlebotomines (Diptera: Psychodidae) in an agroforestry environment of northeast Brazil.

ABSTRACT: Phlebotomine vectors transmit parasites and can cause visceral leishmaniasis (VL) or cutaneous leishmaniasis (TL). Phlebotomine females are hematophagous but need to ingest carbohydrates, possibly promoting the development of protozoan parasites in their digestive tract. The present study evaluated the species composition and abundance across several habitats in a metropolitan landscape, as well as associations among phlebotomines, plants, and local climatic parameters. Three consecutive monthly collections were carried out in an Atlantic Forest fragment, using CDC light traps in peridomestic areas and cashew, coconut, and mango tree.plantations. Eight species of phlebotomine were captured: Evandromyia evandroi, Lutzomyia longipalpis, Psathyromyia shannoni, Sciopemyia sordellii, Evandromyia walkeri, Psychodopygus wellcomei, Nyssomyia whitmani, and Nyssomyia intermedia, primarily from the forest environment. L. longipalpis was confirmed as a species adapted to anthropic environments, while P. wellcomei was shown to be predominately forest-dwelling. Phlebotomines exhibited diversified food consumption patterns in relation to carbohydrate sources. They fed on both native and exotic species of arboreal and shrubby vegetables and gramineous plants.

Anthropophily of Lutzomyia wellcomei (Diptera: Psychodidae) in an Atlantic Forest Conservation Unit in Northeast Brazil

Abstract Lutzomyia wellcomei (Fraiha, Shaw & Lainson) (Diptera: Psychodidae) can act as an important vector of Leishmania (Viannia) braziliensis. This study presents the results of collections carried out in a fragment of Atlantic Forest in a Conservation Unit of Rio Grande do Norte state. Collections occurred over 12 consecutive months using Shannon and CDC traps. A total of 777 sand flies from eight species were collected: Lutzomyia walkeri (Newstead), Lutzomyia evandroi (Costa Lima & Antunes), Lutzomyia wellcomei (Fraiha, Shaw & Lainson), Lutzomyia sordellii (Shannon & Del Ponte), Lutzomyia brasiliensis (Costa Lima), Lutzomyia lenti (Mangabeira), Lutzomyia longipalpis (Lutz & Neiva), and Lutzomyia abonnenci (Floch & Chassignet). Lutzomyia wellcomei was the most abundant species using the Shannon trap (97%) and L. walkeri in the CDC trap (81%). It is important to note the abundance of L. wellcomei in Shannon trap collections, which favors the capture of anthropophilic species. Lutzomyia wellcomei was only present in months where rainfall was above 100mm, confirming it as a species adapted to wetter months.

A new approach to deploy a self-adaptive distributed firewall

Abstract■■■Distributed firewall systems emerged with the proposal of protecting individual hosts against attacks originating from inside the network. In these systems, firewall rules are centrally created, then distributed and enforced on all servers that compose the firewall, restricting which services will be available. However, this approach lacks protection against software vulnerabilities that can make network services vulnerable to attacks, since firewalls usually do not scan application protocols. In this sense, from the discovery of any vulnerability until the publication and application of patches there is an exposure window that should be reduced. In this context, this article presents Self-Adaptive Distributed Firewall (SADF). Our approach is based on monitoring hosts and using a vulnerability assessment system to detect vulnerable services, integrated with components capable of deciding and applying firewall rules on affected hosts. In this way, SADF can respond to vulnerabilities discovered in these hosts, helping to mitigate the risk of exploiting the vulnerability. Our system was evaluated in the context of a simulated network environment, where the results achieved demonstrate its viability.

LVWNet: an hybrid simulation architecture for wireless sensor networks

Internet of Things (IoT) is a reality right now and IoT applications has being applied for many different scenarios. Every IoT scenario has stringent requirements and each new developed application must be tested before being embedded on real devices. There are two main approaches for testing IoT applications, real testbeds and network simulators. Real testbeds are the most accurate test environments, although creating scenarios with a high density of devices or analyze complex wireless sensor networks data (e.g. mobility) can be very costly. Due to limitations of real testbeds, wireless networks simulators are the most used tool for testing new wireless applications. Despite of relying on mathematical models to simulate securely IoT scenarios, it increases the development effort by the need of implementing a different version of the application for testing purposes. Also, the available simulators lacks some important features for prototyping IoT applications. Thus, this work presents the Linux Virtual Wireless Network, a hybrid simulation environment for wireless networks that provides flexibility by virtualization of wireless nodes and topology of the network, also the possibility of connecting real devices to the virtual topology, creating a hybrid scenario that can be used to achieve better analysis and validation of IoT applications.

A Hybrid Architecture for Experimentation in Wireless Sensor Networks

Wireless sensor networks is an emerging technology which can be applied for many scenarios. However, many of them have stringent requirements since performance is a limitation for deployment. The solution for this challenge can be carried out by costly and reliable testbeds for conducting tests on prototypes. On the other hand, a more cost-effectiveness approach based on simulation can achieve similar results with the drawback of using non-real firmware. Thus, this work aims to purpose a new hybrid architecture Based on Linux kernel modules for virtualization and emulation of real Wireless sensor networks. This approach assumes that the devices are in conformance with IEEE 802.11, however, other protocols can be used, like IEEE 802.15.4. Real firmware found in a typical IEEE 802.11 devices is adopted to achieve more accurate results.