Energy-aware Ad Hoc on-demand distance vector routing protocol and optimizing the blocking problem induced in wireless Ad Hoc networks

The purpose of this thesis was to investigate some of the issues related to routing and medium access control protocol in ad hoc networks. In routing protocol, the goal is to tackle the power consumption problem and to present a case for using new cost energy-aware metric for Ad Hoc On-Demand Distance Vector (AODV). The idea of the new cost metric is to be able to avoid routes with a low energy capacity. By using this approach, high efficiency in energy consumption can be achieved in Ad-Hoc networks. The second goal of this thesis was to investigate the blocking problem induced by Request-to-Send/Clear-to-Send (RTS/CTS) mechanism in detail and provide a solution to overcome that problem. To do so, a new parameter is proposed by which the Medium Access control (MAC) protocol will decide when to switch between RTS/CTS mechanism (the 4-way-handshaking) and the Basic Access method (the 2-way-handshaking) in order to reduce the effect of the blocking problem in Ad Hoc networks

Space division multiple access for wireless sensor networks

This dissertation proposed a self-organizing medium access control protocol (MAC) for wireless sensor networks (WSNs). The proposed MAC protocol, space division multiple access (SDMA), relies on sensor node position information and provides sensor nodes access to the wireless channel based on their spatial locations. SDMA divides a geographical area into space divisions, where there is one-to-one map between the space divisions and the time slots. Therefore, the MAC protocol requirement is the sensor node information of its position and a prior knowledge of the one-to-one mapping function. The scheme is scalable, self-maintaining, and self-starting. It provides collision-free access to the wireless channel for the sensor nodes thereby, guarantees delay-bounded communication in real time for delay sensitive applications. This work was divided into two parts: the first part involved the design of the mapping function to map the space divisions to the time slots. The mapping function is based on a uniform Latin square. A Uniform Latin square of order k = m 2 is an k x k square matrix that consists of k symbols from 0 to k-1 such that no symbol appears more than once in any row, in any column, or in any m x in area of main subsquares. The uniqueness of each symbol in the main subsquares presents very attractive characteristic in applying a uniform Latin square to time slot allocation problem in WSNs. The second part of this research involved designing a GPS free positioning system for position information. The system is called time and power based localization scheme (TPLS). TPLS is based on time difference of arrival (TDoA) and received signal strength (RSS) using radio frequency and ultrasonic signals to measure and detect the range differences from a sensor node to three anchor nodes. TPLS requires low computation overhead and no time synchronization, as the location estimation algorithm involved only a simple algebraic operation

Anti-inflammatory potential of Capparis spinosa L. in vivo in mice through inhibition of cell infiltration and cytokine gene expression

Abstract Background Several chronic inflammatory diseases are characterized by inappropriate CD4+ T cell response. In the present study, we assessed the ability of Capparis spinosa L. (CS) preparation to orientate, in vivo, the immune response mediated by CD4+ T cells towards an anti-inflammatory response. Methods The in vivo study was carried out by using the contact hypersensitivity (CHS) model in Swiss mice. Then we performed a histological analysis followed by molecular study by using real time RT-PCR. We also realized a phytochemical screening and a liquid-liquid separation of CS preparation. Results Our study allowed us to detect a significantly reduced edema in mice treated with CS preparations relative to control. CS effect was dose dependent, statistically similar to that observed with indomethacin, independent of the plant genotype and of the period of treatment. Furthermore, our histology studies revealed that CS induced a significant decrease in immune cell infiltration, in vasodilatation and in dermis thickness in the inflammatory site. Interestingly, we showed that CS operated by inhibiting cytokine gene expression including IFN\u3b3, IL-17 and IL-4. Besides, phytochemical screening of CS extract showed the presence of several chemical families such as saponins, flavonoids and alkaloids. One (hexane fraction) out of the three distinct prepared fractions, exhibited an anti-inflammatory effect similar to that of the raw preparation, and would likely contain the bioactive(s) molecule(s). Conclusions Altogether, our data indicate that CS regulates inflammation induced in vivo in mice and thus could be a source of anti-inflammatory molecules, which could be used in some T lymphocyte-dependent inflammatory diseases

Additional file 3: of Anti-inflammatory potential of Capparis spinosa L. in vivo in mice through inhibition of cell infiltration and cytokine gene expression

Raw data relative to Fig. 3. (XLSX 11 kb

Additional file 3: of Capparis Spinosa L. promotes anti-inflammatory response in vitro through the control of cytokine gene expression in human peripheral blood mononuclear cells

Raw data Figure 3. (XLSX 10 kb

Additional file 4: of Capparis Spinosa L. promotes anti-inflammatory response in vitro through the control of cytokine gene expression in human peripheral blood mononuclear cells

Raw data Figure 4 and supplementary figure. (XLSX 50 kb

Additional file 5: Figure S1. of Capparis Spinosa L. promotes anti-inflammatory response in vitro through the control of cytokine gene expression in human peripheral blood mononuclear cells

Effects of Capparis Spinosa’s aqueous fraction on IL-4, IL-17, IL-10, TGF-β and TNF-α expressions in stimulated PBMCs with PHA (5 μg/ml) in culture. (G) IL-4, (H) IL-17, (I) IL-10, (J) TGF-β, (K) TNF-α. incubated for 18 h, doses used 100 and 500 μg/ml. Data represent the mean ± S.D. Data from n = 5 separate experiments. (DOCX 108 kb

Additional file 2: of Capparis Spinosa L. promotes anti-inflammatory response in vitro through the control of cytokine gene expression in human peripheral blood mononuclear cells

Raw data Figure 2. (XLSX 20 kb