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Alterações na ingestão de líquidos em ratas ovariectomizadas alimentadas com dieta hiperlipídica com ou sem reposição de estrógeno
(Universidade Federal de São Carlos, 2022-05-05) Varanda, Tais; Colombari, Débora Simões de Almeida; https://lattes.cnpq.br/1684467594359403; https://lattes.cnpq.br/0455671940971406
In recent decades, obesity, a non-communicable disease, has become a worldwide epidemic. During obesity, reductions in water intake have been described in humans and animals. In addition to obesity, dehydration affects a portion of the Brazilian population, especially in times of warmer weather. Experimentally, dehydration can be induced by water deprivation (WD), which induces thirst, due to the activation of osmoreceptors and the action of ANG II on angiotensin II receptors type 1 (AT1) receptors in the central nervous system (CNS), and ingestion of hypertonic sodium solution, by the action of ANG II on AT1 receptors in the CNS. During menopause, disorders in the water and sodium intake are commonly observed, due to the absence of the hormone estrogen. Experimentally, estrogen treatment in ovariectomized (OVX) rats has been shown to be effective in reducing these changes. Thus, we were aimed to study the daily water and sodium intake in intact females, and in OVX rats lacking 17-β-estradiol (E2) or E2 replacement that were fed a high-fat diet. Possible changes in water and sodium intake induced by 24-hour PH were also studied. In order to study that, Holtzman females (260-300 g) were placed in individual cages, with free access to food, water, and 0.3 M NaCl solution. During one week daily water and sodium intake was registered, while all rats were kept intact and fed with SD, allowing the verification of basal intake values in these animals (baseline week). Last week, the rats underwent OVX or sham surgery (SHAM) and were fed either SD (11% calories from fat) or HFD (46% calories from fat) for 6 weeks. After 3 weeks of diet, part of the OVX rats received treatment with E2 (10μg/day/rat) for the next 4 weeks. Spontaneous ingestion of water and 0.3 M NaCl was recorded daily for 6 weeks, and body weight was assessed weekly. At the end of 6 weeks, for induction of thirst and sodium appetite, the WD-Partial Rehydration (PR) protocol was used. Briefly: the rats were maintained with only chow for 24 h and then, a water burette was offered for 2 h (PR – thirst test), and then an additional burette containing 0.3 M NaCl was offered for another 2 h (sodium appetite test). At the end of the experiments, the analysis of plasma values of insulin, leptin and E2 were performed, and visceral adipose tissue and uterus were collected and weighted. The main findings were: 1) HFD rats, compared to SD rats, had increased body weight gain, visceral adipose tissue and plasma leptin, and all these parameters were potentiated in HFD/OVX rats and reversed by E2 replacement (HFD/ OVX+E2); 2) A reduction in daily water intake was observed in HFD/SHAM or HFD/OVX rats, compared to SD rats with the same treatment, in HFD/OVX+E2 rats the values of spontaneous water intake returned to values similar to those observed at baseline; 3) spontaneous sodium intake was increased in HFD/SHAM rats when compared to SD/SHAM rats; 4) in HFD/OVX rats, E2 treatment (HFD/OVX+E2) restored the increased sodium intake; 5) Compared with SD/SHAM rats, HFD/SHAM rats ingested less water and more sodium when submitted to 24 h of WD; 6) In SD/OVX rats, there was a lower water intake induced by WD, which was not reversed by the E2 treatment; 7) OVX did not change the sodium intake induced by WD in SD rats, but with E2 treatment there was a reduction in sodium intake induced by WD, 8) On the other hand, water intake after WD in HFD/OVX rats was lower than in HFD/SHAM rats, as well as the sodium intake; 9) In HFD rats, E2 treatment restored both water and sodium intake. Therefore, while in SD rats E2 appears to have an inhibitory effect on sodium intake only during WD, in HFD rats the effect appears to be excitatory for both water and sodium intake in spontaneous or WD-induced ingestion.
Influência da textura superficial na indução de vibração por meio de fluxo de ar em sistema piezoelétrico de conversão de energia
(Universidade Federal de São Carlos, 2022-05-05) Rodrigues, André Luis Gunes; Franco, Vitor Ramos; https://lattes.cnpq.br/4590258470207467; https://lattes.cnpq.br/9793420819693280
Piezoelectric Energy Harvesting Systems PZTEH are being used more and more, driven by the development of electronic components called ULP (Ultra Low Power) that demand low energy consumption. This provides the use of energy, previously considered lost. The analysis of vibrational systems with energy conversion by piezoelectric ceramics has been studied and new components developed. This is either in the direct scope of energy conversion with new actuator projects or in the study and development of energy converters, which may act directly with ceramics or their transducer derivatives, with the intention of amplifying the generated energy. Some publications indicate that the use of wind as an inductor or amplifier, in the gain of energy production in a cantilever system exposed to an air flow. Others verified that the physical design interference, analyzing this aerodynamic influence as flutter, galloping effect and vortex, contribute to the amplification of the amplitude of this vibration and, consequently, in the energy generation. The goal of this dissertation is to analyze experimentally and investigative the influence of surface texture on energy gain, by induction and interaction with the wind in a cantilever beam. The drilling of slots, circles holes and surface cavities (same slots and circles figures) will be evaluated in relation to this air interaction (generated turbulence) on the beam, forcing it to vibrate. A piezoelectric transducer, type buzzer (PZT - Titanate Zirconate Lead), will be rigidly attached near the base of the beam, working as an energy transducer. The results obtained showed that the textures applied to the surface of the beams influenced the mechanical properties and the energy generated by each beam. It was concluded that the cantilever beam with lower stiffness and damping is the best choice to be used with systems excited by wind for EH (energy harvesting) produce, and that the texture of surface can be an important factor to increase energy generation.
Manejo de podridões em pós-colheita de atemoia
(Universidade Federal de São Carlos, 2022-05-05) Oliveira, Larissa Vaz de; Yamamoto, Robson Ryu; https://lattes.cnpq.br/2781829944725891; Jesus Junior, Waldir Cintra de; https://lattes.cnpq.br/2614953467362376; https://lattes.cnpq.br/0629873953514837
Atemoya is a hybrid derived from cherimoya (Annona cherimola Mill) and custard apple (Annona squamosa L.), classified as a climacteric fruit (in which the ripening process is maintained after harvest), which makes it very sensitive to post-harvest lesions and injuries. A number of factors can affect the production and quality of the atemoya, rotting has a determining role, causing major losses. Studies has been conducted in order to determine efficient strategies to increase shelf life of fruit. In this sense, use of a modified atmosphere, use of ethylene inhibitor and plastic films, irradiation, edible coatings and thermotherapy can be mentioned. This work had as main objective to present a literature review, as to present existing treatments used for post-harvest management of Atemoya.
Processos oxidativos avançados na produção de água de reúso a partir de efluente sanitário tratado: remoção de contaminantes emergentes
(Universidade Federal de São Carlos, 2022-05-05) Ferreira, Josilei da Silva; Fadini, Pedro Sérgio; https://lattes.cnpq.br/3255060531838427; https://lattes.cnpq.br/8297063619085509
ADVANCED OXIDATION PROCESSES IN THE PRODUCTION OF REUSE WATER FROM TREATED SANITARY SEWAGE: REMOVAL OF CONTAMINANTS OF EMERGING CONCERN. One of the great global challenges nowadays is the maintenance of water supply conditions facing the densification of large population centers and the decline in the availability and quality of freshwater springs. This work focused to study strategies aiming the removal of molecules called contaminants of emerging concern. Investigations were carried out in a pilot system provided by steps such as photochemical oxidation, photoperoxidation and filtration through an activated carbon bed, continuosly fed by a MBR effluent, treating sewage. Preliminary bench studies pointed out great efficiency in the removal of the target compounds (carbamazepine, propranolol, atenolol, caffeine, diclofenac and ibuprofen), when in aqueous solution, using photoperoxidation process, reaching removals treatment greatest than 85% for caffeine and more than 95% for the other compounds. However, these studied compounds were resistant to photochemical oxidation, removing only diclofenac (100%), ibuprofen (64%) and propranolol (24%) and have shown resistance to peroxide oxidation, which did not promote the removal of any of the compounds. Despite promoting consistent oxidation, the photoperoxidation process led to the formation of by-products with potential toxicity when assessed by performing tests with lettuce seeds (L. Sativa). Studies carried out in the pilot system included the use of the activated carbon bed filtration process in addition to the processes pre-evaluated in the bench studies. The photolysis process, very similar to what was witnessed on the bench, was also able to remove diclofenac (100%) and, much less effectively, ibuprofen (9%). Oxidation by hydrogen peroxide and photoperoxidation occurred for all compounds in the order of 60.2 to 83.4%, and higher than 97% when filtered in an activated carbon bed.