105 research outputs found

    RECICLAGEM AGRÍCOLA DE BIOSSÓLIDOS: ASPECTOS AMBIENTAIS E ACEITAÇÃO PÚBLICA

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    A população humana, enquanto parte do ecossistema terrestre, possui comportamentos que agem em sentido contrĂĄrio Ă  manutenção do equilĂ­brio do meio ambiente. Os principais fatores que alteram este equilĂ­brio estĂŁo relacionados ao consumo de recursos e energia e Ă  produção de resĂ­duos. As ĂĄguas residuais domĂ©sticas sĂŁo, basicamente, compostas por ĂĄguas de banho e lavagem, urina, fezes, restos de alimentos, sabĂ”es e detergentes e o seu tratamento, alĂ©m de ser uma questĂŁo de saĂșde pĂșblica, Ă© uma medida de preservação ambiental. O lodo Ă© produzido nas EstaçÔes de Tratamento de Esgoto em quantidades significativas e sua destinação final Ă© um sĂ©rio problema ambiental. Quanto ao gerenciamento deste resĂ­duo, pode-se optar pelo descarte controlado ou a utilização para outras atividades humanas. As alteraçÔes benĂ©ficas nas caracterĂ­sticas fĂ­sicas, quĂ­micas e biolĂłgicas do solo, o aumento da produtividade agrĂ­cola e os consequentes benefĂ­cios socioeconĂŽmicos tornam a reciclagem agrĂ­cola a prĂĄtica mais adequada dentre as formas de disposição final dos lodos residuais. PorĂ©m, a falta de aceitação pĂșblica da utilização de biossĂłlidos, tanto por parte dos produtores quanto pelos consumidores finais, pode ser um fator de inviabilidade da atividade. O presente trabalho tem como objetivo realizar uma reflexĂŁo sobre a aceitação dos alimentos cultivados em solos tratados com biossĂłlidos por parte da sociedade e possĂ­veis propostas de pesquisas futuras sobre a reciclagem agrĂ­cola

    Quantum Fluctuation Theorems

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    Recent advances in experimental techniques allow one to measure and control systems at the level of single molecules and atoms. Here gaining information about fluctuating thermodynamic quantities is crucial for understanding nonequilibrium thermodynamic behavior of small systems. To achieve this aim, stochastic thermodynamics offers a theoretical framework, and nonequilibrium equalities such as Jarzynski equality and fluctuation theorems provide key information about the fluctuating thermodynamic quantities. We review the recent progress in quantum fluctuation theorems, including the studies of Maxwell's demon which plays a crucial role in connecting thermodynamics with information.Comment: As a chapter of: F. Binder, L. A. Correa, C. Gogolin, J. Anders, and G. Adesso (eds.), "Thermodynamics in the quantum regime - Fundamental Aspects and New Directions", (Springer International Publishing, 2018

    Prenatal hypoxia induces increased cardiac contractility on a background of decreased capillary density.

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    Background: Chronic hypoxia in utero (CHU) is one of the most common insults to fetal development and may be associated with poor cardiac recovery from ischaemia-reperfusion injury,yet the effects on normal cardiac mechanical performance are poorly understood. Methods: Pregnant female wistar rats were exposed to hypoxia (12% oxygen, balance nitrogen)for days 10–20 of pregnancy. Pups were born into normal room air and weaned normally. At 10 weeks of age, hearts were excised under anaesthesia and underwent retrograde 'Langendorff' perfusion. Mechanical performance was measured at constant filling pressure (100 cm H2O) with intraventricular balloon. Left ventricular free wall was dissected away and capillary density estimated following alkaline phosphatase staining. Expression of SERCA2a and Nitric Oxide Synthases (NOS) proteins were estimated by immunoblotting. Results: CHU significantly increased body mass (P < 0.001) compared with age-matched control rats but was without effect on relative cardiac mass. For incremental increases in left ventricular balloon volume, diastolic pressure was preserved. However, systolic pressure was significantly greater following CHU for balloon volume = 50 ÎŒl (P < 0.01) and up to 200 ÎŒl (P < 0.05). For higher balloon volumes systolic pressure was not significantly different from control. Developed pressures were correspondingly increased relative to controls for balloon volumes up to 250 ÎŒl (P < 0.05).Left ventricular free wall capillary density was significantly decreased in both epicardium (18%; P <0.05) and endocardium (11%; P < 0.05) despite preserved coronary flow. Western blot analysis revealed no change to the expression of SERCA2a or nNOS but immuno-detectable eNOS protein was significantly decreased (P < 0.001) in cardiac tissue following chronic hypoxia in utero. Conclusion: These data offer potential mechanisms for poor recovery following ischaemia, including decreased coronary flow reserve and impaired angiogenesis with subsequent detrimental effects of post-natal cardiac performance

    Isolation and characterization of a novel 2-sec-butylphenol-degrading bacterium Pseudomonas sp. strain MS-1

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    A novel bacterium capable of utilizing 2-sec-butylphenol as the sole carbon and energy source, Pseudomonas sp. strain MS-1, was isolated from freshwater sediment. Within 30 h, strain MS-1 completely degraded 1.5 mM 2-sec-butylphenol in basal salt medium, with concomitant cell growth. A pathway for the metabolism of 2-sec-butylphenol by strain MS-1 was proposed on the basis of the identification of 3 internal metabolites—3-sec-butylcatechol, 2-hydroxy-6-oxo-7-methylnona-2,4-dienoic acid, and 2-methylbutyric acid—by gas chromatography-mass spectrometry analysis. Strain MS-1 degraded 2-sec-butylphenol through 3-sec-butylcatechol along a meta-cleavage pathway. Degradation experiments with various alkylphenols showed that the degradability of alkylphenols by strain MS-1 depended strongly on the position (ortho ≫ meta = para) of the alkyl substitute, and that strain MS-1 could degrade 2-alkylphenols with various sized and branched alkyl chain (o-cresol, 2-ethylphenol, 2-n-propylphenol, 2-isopropylphenol, 2-sec-butylphenol, and 2-tert-butylphenol), as well as a dialkylphenol (namely, 6-tert-butyl-m-cresol)

    Acoustic Overexposure Increases the Expression of VGLUT-2 Mediated Projections from the Lateral Vestibular Nucleus to the Dorsal Cochlear Nucleus

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    The dorsal cochlear nucleus (DCN) is a first relay of the central auditory system as well as a site for integration of multimodal information. Vesicular glutamate transporters VGLUT-1 and VGLUT-2 selectively package glutamate into synaptic vesicles and are found to have different patterns of organization in the DCN. Whereas auditory nerve fibers predominantly co-label with VGLUT-1, somatosensory inputs predominantly co-label with VGLUT-2. Here, we used retrograde and anterograde transport of fluorescent conjugated dextran amine (DA) to demonstrate that the lateral vestibular nucleus (LVN) exhibits ipsilateral projections to both fusiform and deep layers of the rat DCN. Stimulating the LVN induced glutamatergic synaptic currents in fusiform cells and granule cell interneurones. We combined the dextran amine neuronal tracing method with immunohistochemistry and showed that labeled projections from the LVN are co-labeled with VGLUT-2 by contrast to VGLUT-1. Wistar rats were exposed to a loud single tone (15 kHz, 110 dB SPL) for 6 hours. Five days after acoustic overexposure, the level of expression of VGLUT-1 in the DCN was decreased whereas the level of expression of VGLUT-2 in the DCN was increased including terminals originating from the LVN. VGLUT-2 mediated projections from the LVN to the DCN are likely to play a role in the head position in response to sound. Amplification of VGLUT-2 expression after acoustic overexposure could be a compensatory mechanism from vestibular inputs in response to hearing loss and to a decrease of VGLUT-1 expression from auditory nerve fibers
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