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Low frequency noise is a common problem in aircraft and launch vehicles. New technologies must be investigated to reduce this noise while contributing minimal weight to the structure. This thesis investigates passive and active control methods to improve low frequency sound absorption and transmission loss using acoustic metamaterials. The acoustic metamaterials investigated consist of poro-elastic acoustic heterogeneous (HG) metamaterials and microperforated (MPP) acoustic metamaterials. HG metamaterials consist of poro-elastic material with a periodic arrangement of embedded masses acting as an array of mass-spring- damper systems. MPP acoustic metamaterials consist of periodic layers of micro-porous panels embedded in poro-elastic material. This thesis examines analytically, experimentally, and numerically the behavior of acoustic metamaterials compared to a baseline poro-elastic sample. The development of numerical techniques using finite element analysis will aid in understanding the physics behind their functionality and will influence their design. Design studies are performed to understand the effects of varying the density, size, shape, and placement of the embedded masses as well as the location and distribution of microperforated panels in poro- elastic material. An active HG metamaterial is investigated, consisting of an array of active masses embedded within poro-elastic material. Successful tonal and broadband noise control is achieved using a feedforward, filtered-x LMS control algorithm to minimize the downstream sound pressure level. Low-frequency absorption and transmission loss is successfully increased in the critical frequency range below 500 Hz. Acoustic metamaterials are compact compared to conventional materials and find applications in controlling low-frequency sound radiation in aircraft and launch vehicles. / Master of Science

Mitochondrial processing peptidase (MPP) is a heterodimeric enzyme which belongs to M16B subfamily of metaloendopeptidases. A universal function of this enzyme is in recognition and cleavage of great number of mitochondrial preprotein presequences, which differ in length and amino acid sequence. MPP consists of catalytical β-MPP and probably recognizing α-MPP. The most conservative region in α-MPP is GRL - glycine-rich loop. Its function is supposed in primary interaction with preprotein presequence. It is possible to study conformational change of GRL after binding the substrate by fluorescence experiments. In this diploma thesis the constructs coding the α-MPP with the single reporter tryptophan residue in the position 289 or 299 were prepared using site-directed mutagenesis. These forms of α-MPP were produced in E. coli BL21(DE3)+pGroESL. Activities of MPP dimer containing α-MPP with the single tryptophan residue in the reporter position were compared with MPP from wild type of S. cerevisiae. Used substrate was yeast malate dehydrogenase precursor with fused presequence (pMDH) from three organisms (yeast, mouse and melon). These presequences differ in their length. Activities of MPP dimer containing α-MPP with the single reporter tryptophan residue in the position 289 were about 70 % while...

Diante de pesquisas realizadas com o 5Ultra-som pulsado de baixa intensidade na regeneração de pele de ratos submetidos a queimaduras provocadas por calor (ALVES, 1988) e em pacientes portadores de úlceras tróficas de perna (HILÁRIO, 1993) se propôs estudar os efeitos do ultra-Som pulsado de baixa intensidade em pacientes com Mal de Hansen (MH) cujas manifestações cutâneas eram caracterizadas como o Mal Perfurante Plantar (MPP) e úlceras do tegumento, sendo que o emprego do ultra-som pulsado e de baixa intensidade mostrou-se eficaz na reparação das referidas lesões. O presente trabalho foi realizado em pacientes assistidos pelo Sistema Único de Saúde (SUS) na cidade de Bebedouro-SP lotados no setor de Vigilância Epidemiológica. A casuística constitui-se de seis pacientes apresentando MPP nos quais aplicou-se o ultra-som pulsado (U.S.P.) em uma freqüência de três vezes por semana no mesmo período circadiano. Os tratamentos tiveram duração variando entre vinte e quarenta minutos consoante a extensão das lesões cutânea. Independente do tempo das lesões não foi estabelecido previamente o número de aplicações a serem executadas, mas as aplicações foram realizadas até a obtenção da cicatrização total das lesões. A evolução das lesões até a cicatrização foi feita mediante o emprego de um software especialmente desenvolvido para tal finalidade e documentados fotograficamente. Não houve correlação entre o número de aplicações com o tamanho da lesão ou com o tempo decorrido do aparecimento das mesmas, embora a extensão e a forma das diferentes ulcerações não sejam equivalentes, quer no tempo de evolução, quer na profundidade das lesões, os resultados dos tratamentos com U.S.P. e de baixa intensidade mostraram-se segundo a metodologia de avaliação ser altamente satisfatório para o tratamento de lesões cutâneas decorrente da Hanseníase / Based on researches carried out with the low intensity pulsed ultrasound on the regeneration of burned rat skin previously exposed to heat and on legs trophic ulcers we proposed to study the effects of the low intensity pulsed ultrasound on Hansen’s disease patients whose cutaneous manifestations were characterized as the MPP. The study was carried out on six patients supported by the Public Health Care System (SUS/PHCS) in the city of Bebedouro- SP, crowded on the Epidemiological Observation ward. The low intensity pulsed ultrasonic radiation administrations were carried out three times a week on the same circadian. Irradiation time varied from twenty to forty minutes according to the extension of the lesion. The number of the administrations, which were carried out until the complete lesion cicatrisation in all patients, was not previously stipulated. Evaluation of cicatrisation was carried out making use of software and photographs taken at the beginning of the treatment and after every ten administrations of the pulsed ultrasound until the complete ulcers cicatrisation. It was not observed any correlation between number of ultrasound applications and area of the lesion or age of them. Although extension and shape were not equivalent, according to these results, pulsed low intensity ultrasound can be considered as an adjunctive treatment for cutaneous manifestations of Hansen’s disease

Estrogen stimulation of the medial amygdala (MEA) of the brain promotes male rat mating behavior. However, selective stimulation of either of the estrogen receptor subtypes found in the MEA (ERα or ERβ) does not support mating behavior. We tested the hypothesis that dual stimulation of ERα and ERβ is required to activate estrogen-dependant neural circuits in the MEA responsible for mating by local treatment of MEA with a combination of selective estrogenic agonists: propyl pyrazole triol (PPT, an ERα agonist ) and diarylpropionitrile (DPN, an ERβ agonist) administered to castrated, DHT maintained male rats. Estradiol (E2) or cholesterol (Chol) MEA implants served as positive and negative controls respectively. The animals receiving a mixture of PPT and DPN into the MEA displayed higher levels of mating behavior than the Chol treated animals but lower levels of mating behavior than the E2 treated animals.

Diante de pesquisas realizadas com o 5Ultra-som pulsado de baixa intensidade na regeneração de pele de ratos submetidos a queimaduras provocadas por calor (ALVES, 1988) e em pacientes portadores de úlceras tróficas de perna (HILÁRIO, 1993) se propôs estudar os efeitos do ultra-Som pulsado de baixa intensidade em pacientes com Mal de Hansen (MH) cujas manifestações cutâneas eram caracterizadas como o Mal Perfurante Plantar (MPP) e úlceras do tegumento, sendo que o emprego do ultra-som pulsado e de baixa intensidade mostrou-se eficaz na reparação das referidas lesões. O presente trabalho foi realizado em pacientes assistidos pelo Sistema Único de Saúde (SUS) na cidade de Bebedouro-SP lotados no setor de Vigilância Epidemiológica. A casuística constitui-se de seis pacientes apresentando MPP nos quais aplicou-se o ultra-som pulsado (U.S.P.) em uma freqüência de três vezes por semana no mesmo período circadiano. Os tratamentos tiveram duração variando entre vinte e quarenta minutos consoante a extensão das lesões cutânea. Independente do tempo das lesões não foi estabelecido previamente o número de aplicações a serem executadas, mas as aplicações foram realizadas até a obtenção da cicatrização total das lesões. A evolução das lesões até a cicatrização foi feita mediante o emprego de um software especialmente desenvolvido para tal finalidade e documentados fotograficamente. Não houve correlação entre o número de aplicações com o tamanho da lesão ou com o tempo decorrido do aparecimento das mesmas, embora a extensão e a forma das diferentes ulcerações não sejam equivalentes, quer no tempo de evolução, quer na profundidade das lesões, os resultados dos tratamentos com U.S.P. e de baixa intensidade mostraram-se segundo a metodologia de avaliação ser altamente satisfatório para o tratamento de lesões cutâneas decorrente da Hanseníase / Based on researches carried out with the low intensity pulsed ultrasound on the regeneration of burned rat skin previously exposed to heat and on legs trophic ulcers we proposed to study the effects of the low intensity pulsed ultrasound on Hansen’s disease patients whose cutaneous manifestations were characterized as the MPP. The study was carried out on six patients supported by the Public Health Care System (SUS/PHCS) in the city of Bebedouro- SP, crowded on the Epidemiological Observation ward. The low intensity pulsed ultrasonic radiation administrations were carried out three times a week on the same circadian. Irradiation time varied from twenty to forty minutes according to the extension of the lesion. The number of the administrations, which were carried out until the complete lesion cicatrisation in all patients, was not previously stipulated. Evaluation of cicatrisation was carried out making use of software and photographs taken at the beginning of the treatment and after every ten administrations of the pulsed ultrasound until the complete ulcers cicatrisation. It was not observed any correlation between number of ultrasound applications and area of the lesion or age of them. Although extension and shape were not equivalent, according to these results, pulsed low intensity ultrasound can be considered as an adjunctive treatment for cutaneous manifestations of Hansen’s disease

Massive deployment of wireless IoT (Internet of Things) devices makes replacement or recharge of batteries expensive and impractical for some applications. Energy harvesting is a promising solution, and various designs are proposed to harvest power from ambient resources including thermal, vibrational, solar, wind, and RF sources. Among these ambient resources, AC powerlines are a stable energy source in an urban environment. Many researchers investigated methods to exploit this stable source of energy to power wireless IoT devices. The proposed circuit aims to harvest energy from AC powerlines with a wide input range of from 10 to 50 A. The proposed system includes a wake-up circuit and is capable of cold-start. A buck-boost converter operating in DCM is adopted for impedance matching, where the impedance is rather independent of the operation conditions. So, the proposed system can be applied to various types of wireless sensor nodes with different internal impedances. Experimental results show that the proposed system achieves an efficiency of 80.99% under the powerline current of 50 A. / M.S. / Nowadays, with the magnificent growth of IoT devices, a reliable, and efficient energy supply system becomes more and more important, because, for some applications, battery replacement is very expensive and sometimes even impossible. At this time, a well-designed self-contained energy harvesting system is a good solution. The energy harvesting system can extend the service life of the IoT devices and reduce the frequency of charging or checking the device. In this work, the proposed circuit aims to harvest energy from the AC power lines, and the harvested power intends to power wireless sensor nodes (WSNs). By utilizing the efficient and self-contained EH system, WSNs can be used to monitor the temperature, pressure, noise level and humidity etc. The proposed energy harvesting circuit was implemented with discrete components on a printed circuit board (PCB). Under a power line current of 50 A @ 50 Hz, the proposed energy harvesting circuit can harvest 156.6 mW, with a peak efficiency of 80.99 %.

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