Implementing Institute of Electrical and Electronics Engineers (IEEE) 802.11 Standard Medium Access Control Protocol for Wireless Local Area Networks (LANS) on a Laboratory Hardware Prototype

Wireless Local Area Networks (LANs) are extremely convenient, flexible, and easy to deploy. All LANs in which multiple hosts must access the same medium use a Medium Access Control (MAC) protocol to coordinate channel access. The MAC is part of the Data Link Layer of the Open Systems Interconnection (OSI) Reference Model. One MAC protocol in extensive use today is the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard. Since IEEE 802.11 devices are so prevalent in today s world, many researcher are exploring modifications and enhancements to the protocol. There are several well developed analytical and simulation models for IEEE 802.11 available to researchers, yet one significant obstacle remains: the lack of a means to obtain experimental data based on proposed protocol changes. Without real world experimental data, researchers lack the ability to test out their proposals in a real world environment. To fill this need, this thesis created a hardware prototype from which researchers can obtain experimental data about IEEE 802.11. This hardware prototype can now be used by researchers to gain real world data on their proposed modifications to IEEE 802.11

Conjugated materials containing dithienometalloles

The development of new semiconducting conjugated polymers has been an important aspect of plastic electronics research since the early days of the field, as it allows the optoelectronic properties to be tuned for various applications. Dithienometalloles, which consist of a 2,2’-bithiophene fused with a bridging heteroatom, have been an important class of monomers for some time. The heteroatom serves an important role, both in holding the bithiophene unit rigidly coplanar and also in tuning the energetics of the system. In addition, these moieties often possess alkyl chains located on the bridging heteroatom that serve to confer solubility and processability to the final polymers. In this thesis we report the synthesis and properties of a number of dithienometallolecontaining polymers, in which the necessary solubilising groups have been moved from the bridging heteroatom to the adjacent thiophene backbone of the dithienometallole. This enabled the preparation of novel, soluble arsole-containing conjugated polymers. These dithienoarsole containing materials were used in both organic field effect transistors and organic photovoltaic devices, showing promising performances as well as significantly improved air stability over their phosphorus-containing analogues. The effect of changing the bridging heteroatom in dithienometalloles was also studied by comparing the optoelectronic properties and device performances of polymers with carbonyl, silicon, germanium, and nitrogen bridging groups. Finally, dithienopyrrole-based sensors were developed that showed substantial colour changes on exposure to basic solutions, as well as potential for use as readily dopable materials for electronic applications.Open acces

New therapies and management strategies in the treatment of asthma: patient-focused developments

It is increasingly recognized that large proportions of patients with asthma remain poorly controlled with daily symptoms, limitation in activities, or severe exacerbations despite traditional treatment with inhaled corticosteroids and other agents. This suggests that there is considerable scope for the refinement of traditional guidelines on the use of inhaled therapies in asthma and also a need for the development of novel therapeutic agents, particularly for the treatment of severe asthma. This review aims to discuss a range of emerging treatment approaches in asthma. Firstly, we will set the scene by highlighting the importance of achieving good asthma control in a patient-focused manner and discussing recent work that has furthered our understanding of asthma phenotypes and paved the way for patient-specific treatments. Secondly, we will review new strategies to better use the existing therapies such as inhaled corticosteroids and long-acting β2-agonists that remain the mainstay of treatment for most patients. Finally, we will review the novel therapies that are becoming available, both pharmacological and interventional, and discuss their likely place in the management of this complex disease