Liquid-liquid equilibrium data and thermodynamic modeling of systems involved in the biodiesel production in terms of acylglycerols, free fatty acids, ethyl esters, and ethanol at 303.2 and 318.2 K and local pressure

Researches on renewable fuels as biodiesel are being done due to the global concern about the shortage of non-renewable natural energy resources. For the biodiesel production, vegetable oils are transesterified with short-chain alcohols, generating intermediate compounds as monoacylglycerols (MAG) and diacylglycerols (DAG). In order to understand the first stage of the transesterification reaction during the biodiesel production, this study reported experimental liquid-liquid equilibrium (LLE) data and the thermodynamic modeling of systems composed of refined oil (soybean, cottonseed, and rice bran) + commercial mixture of partial acylglycerols (MAG and DAG) + free fatty acids (FFA) + fatty acid ethyl esters (FAEE) + ethanol at T = (303.2 and 318.2) K. The LLE experimental data were thus used to adjust the NRTL model parameters and to evaluate three parameters sets of the UNIFAC model. Calculated results by the NRTL model were well correlated to the experimental ones, with mass deviations up to 0.32%, whereas the deviations calculated for the UNIFAC model ranged from 1.04 to 9.46%. FFA and MAG exhibited preference to the solvent-rich phase, whereas FAEE and DAG preferred the oil-rich phase. New and more complex LLE data considering partial acylglycerols, FFA, besides the FAEE, as here reported, can assist to describe the real behavior of the transesterification step involved in the biodiesel production process and, consequently, its optimization507CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP406856/2013–3; 305870/2014–9; 406963/2016–9; 308924/2017–710890972014/21252–0, 2016/10636–8, 2017/21607–1, 2018/13207–

Suprasellar germ cell tumor in a dog Tumor supra-selar de células germinativas em um cão

A case of suprasellar germ cell tumor is described in a 6-year -old Airedale Terrier bitch that presented behavioral changes and abrupt onset of blindness. The neoplasm compressed the ventral surface of the cerebrum from the level of basal ganglia to the mesencephalon. Histologically the neoplasm consisted of nests and trabeculae of round to polygonal cells that occasionally surround tubules and cysts formed by columnar cells. Neoplastic cells are immunopositive for cytokeratin and alpha-fetoprotein. The diagnosis was based on location, histological appearance and on the immunohistochemical staining.<br>É descrito um caso de tumor de células germinativas supra-selar em numa cadela Airedale Terrier de seis anos de idade, que apresentou transtornos do comportamento e aparecimento abrupto de cegueira. O neoplasma comprimia a superfície ventral do cérebro desde a altura dos núcleos basais até o mesencéfalo. Histologicamente, o neoplasma consistia de ninhos e trabéculas de células redondas ou poligonais que ocasionalmente arranjavam-se ao redor de túbulos e cistos formados por células colunares. As células neoplásicas foram positivas na imunoistoquímica para citoqueratina e a-fetoproteína. O diagnóstico foi feito com base na localização do tumor, no seu aspecto histológico e nos resultados da marcação imunoistoquímica

Avaliação dos resultados clínicos após cirurgia descompressiva em cães com doença de disco intervertebral Evaluation of clinical results of decompressive surgery in dogs with degenerative disk disease

Avaliaram-se os resultados clínicos após realização de cirurgia descompressiva em 45 cães com doença do disco intervertebral cervical ou toracolombar. Após a cirurgia, 35 cães (77,8%) recuperaram-se totalmente, oito (17,8%) parcialmente e dois (4,4%) não apresentaram alteração do quadro inicial. Em oito cães com paraplegia e perda da sensibilidade dolorosa profunda houve completa melhora do quadro clínico, com recuperação total em 62,5% dos casos. Em quatro cães com tetraparesia, a cirurgia foi eficaz. A cirurgia descompressiva (slot cervical e hemilaminectomia toracolombar), com a retirada do material do disco do interior do canal vertebral, foi uma forma efetiva de gerar melhora do quadro funcional.<br>Clinical results after decompressive surgery were evaluated in 45 dogs with cervical or thoracolumbar intervertebral disk disease. After surgery, 35 dogs recovered totally, eight (17.8%) partially, and two (4.4%) did not present any change in clinical findings. Eight dogs with paraplegy and loss of deep pain perception showed improvement, with total recovering in 62.5% of cases. Surgery was effective in four dogs with tetraparesy. Decompressive surgery (cervical slot or hemilaminectomy), with removal of disk material from inside the vertebral canal, was an effective form to produce functional improvement in dogs with this disease