A História da Alimentação: balizas historiográficas

Os M. pretenderam traçar um quadro da História da Alimentação, não como um novo ramo epistemológico da disciplina, mas como um campo em desenvolvimento de práticas e atividades especializadas, incluindo pesquisa, formação, publicações, associações, encontros acadêmicos, etc. Um breve relato das condições em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biológica, a econômica, a social, a cultural e a filosófica!, assim como da identificação das contribuições mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histórica, foi ela organizada segundo critérios morfológicos. A seguir, alguns tópicos importantes mereceram tratamento à parte: a fome, o alimento e o domínio religioso, as descobertas européias e a difusão mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rápido balanço crítico da historiografia brasileira sobre o tema

Effect of plasticizers on a PVC sensing phase for evaluation of water contamination by aromatic hydrocarbons and fuels using infrared spectroscopy

a b s t r a c t The effects of di-2-ethylhexylsebacate (DOS), di-2-ethylhexylphthalate (DOP) and 2-nitro-phenyloctylether (NPOE) plasticizers on a PVC sensing phase for evaluation of water contamination by aromatic hydrocarbons and fuels were investigated. The performance of each film was assessed by means of figures of merit obtained from analytical curves constructed in different wavenumbers. A mixture design (simplex centroid) with the BTEX compounds was performed in order to evaluate cross-interferences and interaction effects. For preparation of the sensing phase, a mixture of PVC with 25% of the plasticizer and 0.3% of the stabilizer Tinuvin P (2-2 -hydroxy-5-tert-octylphenyl-benzotriazol) dissolved in THF was used. The results show that NPOE and DOP plasticizers present similar performances, while DOS provides better values of sensitivity and detection limit for all compounds. With the use of DOS the detection limits were 2.4, 0.4, 1.5 and 1.2 mg L −1 for BTEX, respectively. Regarding the study of multi-component interactions, it was observed that benzene and xylenes do not show interferences from the other analytes of the mixture at the wavenumbers of 676 and 1522 cm −1 , respectively. Ethylbenzene and toluene undergo spectral interferences and interaction effects in all peaks evaluated, requiring a multivariate calibration for their determination. In the analysis of water contaminated by fuels, a 3-D plot as a function of benzene, toluene and xylenes concentrations as well as the principal component analysis of the spectral data presented well-defined groups for each kind of contamination (gasoline A, gasoline C, diesel and diesel with 2% of biodiesel). These results demonstrate the potential of the proposed method, employing a PVC sensing phase, with transmittance measurements in the mid-infrared, for determination of contamination of waters by aromatic hydrocarbons. In conclusion, PVC films plasticized with DOS can be useful for studies of water contamination based on transmittance measurements in the mid-infrared region, avoiding the drawbacks of ATR methods

A PVC sensing phase for determination of BTEX in water employing mid-infrared spectroscopy

Abstract The evaluation of PVC films, cast with 2-(2-hydroxy-5-tert-octylphenyl)benzotriazol (Tinuvin) as stabiliser (0.3%) and di-2-ethylhexyl phthalate (DOP) as plasticiser (25 or 40%), for use as sensing phases for benzene, toluene, ethylbenzene and xylene (BTEX) determinations, based on transmittance measurements in the mid-infrared (MIR) region, is described. Measurements were carried out by inserting a PVC sensing phase into a vial, which was then completely filled with the hydrocarbon sample solution. Afterwards, the sensing phase was removed from the vial and placed in the optical path of a spectrophotometer for acquiring absorbance spectra from 12,800 to 650 cm À1 . Kinetic measurements showed that the films reached saturation within 180 min for all BTEX compounds. Analytical curves were constructed for BTEX compounds in the 0-80 mg L À1 concentration range, showing, respectively, detection limits and sensitivities (expressed as the slope of the analytical curves) of 5.0 mg L À1 and 2.6 Â 10 À5 L mg À1 for benzene (measured at 688 cm À1 ), 6.9 mg L À1 and 3.6 Â 10 À5 L mg À1 for toluene (at 728 cm À1 ), 9.0 mg L À1 and 4.7 Â 10 À5 L mg À1 for ethylbenzene (at 695 cm À1 ), and 4.0 mg L À1 and 3.7 Â 10 À5 L mg À1 for xylene (at 778 cm À1 ), when PVC film with 25% plasticiser was employed. The sensitivity was increased when 40% of plasticiser was used in the film preparation. These results demonstrate the feasibility of using transmittance measurements in the mid-infrared region for determining BTEX compounds in water, after their extraction by a PVC film.

Evaluation of a PVC sensing phase for determination of chlorinated hydrocarbons in water by mid-infrared spectroscopy

In this work, mid-infrared spectroscopy has been employed to investigate the effect of amount (25 or 40%) and type of plasticiser (di-2-ethylhexyl sebacate (DOS), di-2-ethylhexyl phthalate (DOP) and 2-nitrophenyl octyl ether (NPOE)) on the analytical response of a poly(vinylchloride) (PVC) sensing phase for the determination of the chlorinated hydrocarbons (chlorobenzene (ClB), trichloroethylene (TCE) and trichlorobenzene (TCB)) in water. It was observed that films with 40% of plasticiser provided higher sensitivity and lower limits of detection than those with 25%, although the later films are easier to handle. A similar behaviour was also observed for sensing phases prepared with the plasticisers NPOE and DOS. By employing a DOS-based PVC sensing phase and extraction time of 60 min, limits of detection of 0.3, 0.6, and 0.5 mg L-1 were obtained for chlorobenzene, trichloroethylene and trichlorobenzene, respectively.Neste trabalho, a espectroscopia no infravermelho médio foi utilizada para investigar o efeito da quantidade (25 ou 40%) e do tipo de plastificante (di-2-etilhexil ftalato (DOP), di-2-etilhexil sebacato (DOS) e 2-nitrofenil octil éter (NPOE)) na resposta analítica de uma fase sensora de poli(cloreto de vinila) (PVC) para a determinação de hidrocarbonetos clorados (clorobenzeno (ClB), tricloroetileno (TCE) e triclorobenzeno(TCB)) em água. Foi observado que os filmes com 40% de plastificante geraram maior sensibilidade e menores limites de detecção que aqueles preparados com 25%, embora esses últimos sejam de manipulação mais fácil. Um comportamento similar foi também observado para fases sensoras preparadas com os plastificantes NPOE e DOS. Com o uso da fase sensora de PVC-DOS e um tempo de extração de 60 min, foram obtidos limites de detecção de 0,3, 0,6 e 0,5 mg L-1 para clorobenzeno, tricloroetileno e triclorobenzeno, respectivamente.14701477Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Diet compounds, glycemic index and obesity-related cardiac effects

Background: Diet compounds may influence obesity-related cardiac oxidative stress and metabolic sifting. Carbohydrate-rich diet may be disadvantageous from fat-rich diet to cardiac tissue and glycemic index rather than lipid profile may predict the obesity-related cardiac effects.Materials and methods: Male Wistar rats were divided into three groups (n=8/group): (C) receiving standard chow (3.0 kcal/g); (CRD) receiving carbohydrate-rich diet (4.0 kcal/g), and (FRD) receiving fat-rich diet (4.0 kcal/g). Rats were sacrificed after the oral glucose tolerance test (OGTT) at 60 days of dietary treatments. Lipid profile and oxidative stress parameters were determined in serum. Myocardial samples were used to determine oxidative stress, metabolic enzymes, glycogen and triacylglycerol.Results: FRD rats showed higher final body weight and body mass index than CRD and C. Serum cholesterol and low-density lipoprotein were higher in FRD than in CRD, while triacylglycerol and oxidized low-density lipoprotein cholesterol were higher in CRD than in FRD. CRD rats had the highest myocardial lipid hydroperoxide and diminished superoxide dismutase and catalase activities. Myocardial glycogen was lower and triacylglycerol was higher in CRD than in C and FRD rats. Although FRD rats had depressed myocardial-reducing power, no significant changes were observed in myocardial energy metabolism. Myocardial beta-hydroxyacyl coenzyme-A dehydrogenase and citrate synthase, as well as the enhanced lactate debydrogenase/citrate synthase ratio indicated that fatty acid degradation was decreased in CRD rats. Glycemic index was positively correlated with obesity-related cardiac effects.Conclusions: Isoenergetic carbohydrate-rich and fat-rich diets induced different degree of obesity and differently affected lipid profile. Carbohydrate-rich diet was deleterious relative to fat-rich diet in the heart enhancing lipoperoxidation and shifting the metabolic pathway for energy production. Glycemic index rather than dyslipidemic profile may predict the obesity effects on cardiac tissue. (C) 2007 Elsevier B.V. All rights reserved

Erratum: stematic review and meta-analysis of individual participant data (Clin Epidemiol. 2018, 10, 363–379)

Page 363, affiliations section, “On behalf of the ICARA Study Group” should instead read “and the ICARA study group”