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Diagnosing and treating acute severe and recurrent antivenom-related anaphylaxis (ARA) is challenging and reported experience is limited. Herein, we describe our experience of severe ARA in patients with neurotoxic snakebite envenoming in Nepal. Patients were enrolled in a randomised, double-blind trial of high vs. low dose antivenom, given by intravenous (IV) push, followed by infusion. Training in ARA management emphasised stopping antivenom and giving intramuscular (IM) adrenaline, IV hydrocortisone, and IV chlorphenamine at the first sign/s of ARA. Later, IV adrenaline infusion (IVAI) was introduced for patients with antecedent ARA requiring additional antivenom infusions. Preantivenom subcutaneous adrenaline (SCAd) was introduced in the second study year (2012). Of 155 envenomed patients who received ≥ 1 antivenom dose, 13 (8.4%), three children (aged 5−11 years) and 10 adults (18−52 years), developed clinical features consistent with severe ARA, including six with overlapping signs of severe envenoming. Four and nine patients received low and high dose antivenom, respectively, and six had received SCAd. Principal signs of severe ARA were dyspnoea alone (n=5 patients), dyspnoea with wheezing (n=3), hypotension (n=3), shock (n=3), restlessness (n=3), respiratory/cardiorespiratory arrest (n=7), and early (n=1) and late laryngeal oedema (n=1); rash was associated with severe ARA in 10 patients. Four patients were given IVAI. Of the 8 (5.1%) deaths, three occurred in transit to hospital. Severe ARA was common and recurrent and had overlapping signs with severe neurotoxic envenoming. Optimising the management of ARA at different healthy system levels needs more research. This trial is registered with NCT01284855.

Wireless charging of electric vehicle (EV) batteries by inductive power transfer (IPT) offers unique advantages compared to conventional conductive chargers. Due to the absence of a galvanic connection, the charging process requires no user interaction and no moving of mechanical components. For public transport systems, e.g., public buses or tramways, this makes possible a fully automated opportunity charging at bus stations, taxicab stands, or traffic lights. The schematic of wireless battery charger (WBC) is made of two stages, one is transmitter stage and another one is receiver stage. Both the stages include coils and capacitors to resonate at the supply frequency along with power conversion circuits. The transmitter coil is buried in the ground while receiving coil is situated in the vehicle. Based on the connection of resonating capacitors four topologies are possible which can be divided into two arrangements i) transmitter capacitor in series while receiver capacitor is in either series or in parallel, giving rise to SS and SP topologies, ii) transmitting capacitor in parallel while receiving capacitor is in either series or in parallel, giving rise to PS and PP topologies. In the thesis, these topologies have been studied in detail in terms of efficiency, power sizing of supply inverter and resonating coils, behavior under the extreme condition of open and short circuit of the receiver. Power conversion circuitry of a WBC system includes a diode rectifier to supply the load with a direct voltage and resorts to different solutions for charging the battery. The two most used solutions are either in a straightforward manner through the diode rectifier or through a chopper in cascade to the diode rectifier. These two arrangements have been discussed and compared in terms of efficiency and power sizing of supply inverter and transmitting and receiving coil, including the selection of the optimum chopper input voltage. Due to aging and thermal effect, the parameters of the reactive components of a WBC system may change and this can deviates the resonance frequency from the supply frequency. In this thesis the impact of such mismatch on efficiency and supply inverter power sizing factor of WBC with SS topology has been studied. Three supply frequency updating techniques to keep in resonance either the transmitter stage or the receiver stage or the impedance seen from power supply have been investigated. The thesis continues with the study of high power WBC systems which includes power supply architecture, core material and coil geometry. A review of different power supply architectures such as single phase with two stage and parallel topologies including their merits and demerits have been presented. Reviewing some paper on coil geometry, DD coil is found to be suitable for high power application. Using JMAG simulation tool, a transmitter track of three DD coils and a receiver with one DD coil has been analyzed when receiver is moving on the transmitting track. Due to disfavor of ferrite as a core material for high-power WBC system, a varieties of different powdered magnetic materials have been considered here and compared in terms of saturated value of the magnetic flux density, magnetic properties -like dependency of their permeability on temperature, magnetic field strength and frequency-, power losses and cost. At last, two methods to model the WPT system have been considered. The methods model the system by considering the envelop of the signals.