2,958 research outputs found
A chromophoric study of 2-ethylhexyl p-methoxycinnamate
AbstractUltraviolet absorption spectra of 2-ethylhexyl p-methoxycinnamate have been recorded in different solvents and calculated using the time dependent density functional theory. The calculations were performed with the aid of B3LYP, PBE1PBE, M06, and PBEPBE functionals and 6-31+G(2d) basis set. The geometries were initially optimized using PM5 semiempirical method for the conformational search. The calculations of excited states were carried out using the time dependent with IEF-PCM solvent reaction field method. The experimental data were obtained in the wavelength range from 200 to 400nm using 10 different solvents. The TD-PBE1PBE method shows the best agreement to the experimental results
Microencapsulation of tomato (Solanum lycopersicon L.) pomace ethanolic extract by spray drying: optimization of process conditions
Microencapsulation by spray-drying is a process used in the stabilization of active
compounds from various natural sources, such as tomato by-products, with the purpose to be
used as additives in the food industry. The aim of this work was to study the effects of wall material
and spray drying conditions on physicochemical properties of microcapsules loaded with lycopene
rich extract from tomato pomace. The assays were carried out with ethanolic tomato pomace extract
as core material and arabic gum or inulin as wall materials. A central composite rotatable design was
used to evaluate the effect of drying air inlet temperature (110–200 C) and concentration of arabic
gum (5–35 wt %) or inulin (5–25 wt %) on the antioxidant activity, encapsulation efficiency, loading
capacity, and drying yield. SEM images showed that the produced particles were in the category of
skin-forming structures. The most suitable conditions, within the ranges studied, to obtain lycopene
loaded microparticles were a biopolymer concentration of 10 wt % for both materials and an inlet
temperature of 200 and 160 C for arabic gum and inulin, respectively. Arabic gum and inulin
possessed a good performance in the encapsulation of tomato pomace extract by spray drying. It is
envisaged that the capsules produced have good potential to be incorporated in foods systems with
diverse chemical and physical propertiesinfo:eu-repo/semantics/publishedVersio
Origin of Spin Incommensurability in Hole-doped S=1 Chains
Spin incommensurability has been recently experimentally discovered in the
hole-doped Ni-oxide chain compound (G. Xu {\it
al.}, Science {\bf 289}, 419 (2000)). Here a two orbital model for this
material is studied using computational techniques. Spin IC is observed in a
wide range of densities and couplings. The phenomenon originates in
antiferromagnetic correlations ``across holes'' dynamically generated to
improve hole movement, as it occurs in the one-dimensional Hubbard model and in
recent studies of the two-dimensional extended t-J model. The close proximity
of ferromagnetic and phase-separated states in parameter space are also
discussed.Comment: RevTex, 4 pages, 4 figures (eps
Myofibroma of the oral cavity. A rare spindle cell neoplasm
Myofibroma is an uncommon spindle cell neoplasm rarely found in oral cavity. Typically, this lesion is seen in neonates and infants with few cases reported in adults patients. In the oral cavity, myofibroma occurs within the submucosal or intramuscular tissue and has a predilection by the tongue, buccal mucosa and lips. Microscopically, a typical biphasic pattern can be observed. Misdiagnosis included benign and malignant spindle cell lesions of nerve tissue or smooth muscle origin, such as neurofibroma, leiomyoma and sarcomas. Thus, immunohistochemical staining is a useful tool to identify the nature of neoplastic cells and to reach an accurate diagnosis. An immunohistochemical panel consisting of antibodies to vimentin, SMA, HHF-35, S-100p and desmin must be achieved. In most cases, positivity for vimentin, SMA and HHF-25 can be observed. Our report describes a solitary myofibroma of the tongue of a 23-year-old man with emphasis in clinical, histopathological and immunohistochemical features of this lesion
Low-Protein Diet during Lactation and Maternal Metabolism in Rats
Some metabolic alterations were evaluated in Wistar rats which received control or low-protein (17%; 6%) diets, from the pregnancy until the end of lactation: control non-lactating (CNL), lactating (CL), low-protein non-lactating (LPNL) and lactating (LPL) groups. Despite the increased food intake by LPL dams, both LP groups reduced protein intake and final body mass was lower in LPL. Higher serum glucose occurred in both LP groups. Lactation induced lower insulin and glucagon levels, but these were reduced by LP diet. Prolactin levels rose in lactating, but were impaired in LPL, followed by losses of mammary gland (MAG) mass and, a fall in serum leptin in lactating dams. Lipid content also reduced in MAG and gonadal white adipose tissue of lactating and, in LPL, contributed to a decreased daily milk production, and consequent impairment of body mass gain by LPL pups. Liver mass, lipid content and ATP-citrate enzyme activity were increased by lactation, but malic enzyme and lipid: glycogen ratio elevated only in LPL. Conclusion. LP diet reduced the development of MAG and prolactin secretion which compromised milk production and pups growth. Moreover, this diet enhanced the store of lipid to glycogen ratio and suggests a higher risk of fatty liver development
Evaluation of the productivity, content and nutrient use efficiency in genotypes of Eucalyptus spp. in Jequitinhonha valley, MG
A hibrida\ue7\ue3o de esp\ue9cies de eucalipto possibilita a
obten\ue7\ue3o de h\uedbridos mais produtivos e com alta
efici\ueancia de absor\ue7\ue3o e/ou utiliza\ue7\ue3o de
nutrientes, dependendo das esp\ue9cies combinadas. Neste contexto, o
presente trabalho, conduzido na regi\ue3o do Vale do Jequitinhonha,
Minas Gerais, teve por objetivos: determinar a produtividade, o
conte\ufado e a efici\ueancia de utiliza\ue7\ue3o de N, P, K,
Ca e Mg de h\uedbridos interespec\uedficos de Eucalyptus spp.
Para tanto, mediu-se o di\ue2metro \ue0 altura do peito (DAP) de
todas as \ue1rvores presentes em cada parcela, e abateram-se
tr\ueas \ue1rvores com di\ue2metro correspondente ao da
\ue1rvore m\ue9dia. Procedeu-se \ue0 cubagem das \ue1rvores
pelo m\ue9todo de Smallian, utilizando a altura, o di\ue2metro e a
espessura de casca na base e a 25, 50, 75 e 100 % da altura comercial.
O peso de material fresco do lenho, da casca, das folhas e dos galhos
foi determinado no campo, e desses componentes se coletaram amostras
para determina\ue7\ue3o do peso da mat\ue9ria seca. As amostras
do tronco consistiram de discos coletados, com casca, na base e a 25,
50, 75 e 100% da altura comercial. As amostras de tecido vegetal foram
analisadas para: N, P, K, Ca e Mg. Os resultados obtidos n\ue3o
indicaram diferen\ue7as significativas para a produ\ue7\ue3o de
biomassa de copa entre os h\uedbridos de eucalipto em
conseq\ufc\ueancia de apresentarem mesma idade. Entretanto, a
produ\ue7\ue3o de biomassa de tronco apresentou diferen\ue7as
significativas sendo os h\uedbridos de Eucalyptus urophylla S. T.
Blake proveniente de poliniza\ue7\ue3o natural mais produtivo em 50
e 69% em compara\ue7\ue3o aos h\uedbridos de Eucalyptus urophylla
W. Hill. Ex Maiden com Eucalyptus grandis Dehnh.e de Eucalyptus
urophylla com descendentes do cruzamento de Eucalyptus camaldulensis
com Eucalyptus grandis respectivamente. Al\ue9m disso, aqueles
h\uedbridos foram os que alocaram maior quantidade de biomassa no
tronco (92,3%) em rela\ue7\ue3o \ue0 copa (7,7%), e ainda foram
os mais eficientes na absor\ue7\ue3o e utiliza\ue7\ue3o de N,
P, K, Ca e Mg. Concluiu-se que: 1) h\uedbridos de Eucalyptus
urophylla provenientes de poliniza\ue7\ue3o natural ou controlada
n\ue3o apresentam diferen\ue7a na produ\ue7\ue3o de biomassa de
copa quando avaliados numa mesma idade; 2) a poliniza\ue7\ue3o
controlada de Eucalyptus urophylla com Eucalyptus grandis e com
descendentes do cruzamento de Eucalyptus camaldulensis com Eucalyptus
grandis reduz a produ\ue7\ue3o de biomassa de tronco; 3)
h\uedbridos de Eucalyptus urophylla provenientes de
poliniza\ue7\ue3o natural s\ue3o mais produtivos e mais
eficientes na absor\ue7\ue3o e utiliza\ue7\ue3o de N, P, K, Ca
e Mg e 4) h\uedbridos de Eucalyptus urophylla provenientes de
descendentes do cruzamento de Eucalyptus camaldulensis com Eucalyptus
grandis s\ue3o menos produtivos e menos eficientes na
absor\ue7\ue3o e utiliza\ue7\ue3o de N, P, K, Ca e Mg.The hybridization of eucalyptus species can provide more productive
hybrids and with a high efficiency of nutrient absorption and, or,
nutrient use, depending on the combined species. In this context, the
present work was undertaken in the Jequitinhonha Valley region, Minas
Gerais, and its objectives were: to determine the productivity, content
and use efficiency of N, P, K, Ca and Mg in interspecific hybrids of
Eucalyptus spp. In each plot, the diameters were measured at breast
height (DBH) in all the trees, and three trees with diameter similar to
the average mean were felled. The volume of the trees was estimated by
the Smallian method, using the height, diameter and the bark thickness
at the base and at 25, 50, 75 and 100 % of the commercial height. The
fresh weight of the wood, bark, leaves and branches was determined in
the field, and samples from them were collected for the determination
of dry matter. The log samples consisted of collected disks with bark,
from the base and at 25, 50, 75 and 100 % of the commercial height. The
samples of vegetable tissues were analyzed for: N, P, K, Ca and Mg. The
results obtained did not show significant differences for the
production of crown biomass between the eucalyptus hybrids of the same
age. However, the production of log biomass presented significant
differences and the naturally pollinated hybrids of Eucalyptus
urophylla were 50.0 % and 69.0 % more productive compared with the
hybrids of Eucalyptus urophylla with Eucalyptus grandis and
Eucalyptus urophylla with descendants of the crossing of Eucalyptus
camaldulensis with Eucalyptus grandis, respectively. Also, these
hybrids allocated larger amount of biomass in the log (92.3 %) in
relation to the crown (7.7 %), and they were more efficient in the
absorption and use of N, P, K, Ca and Mg. The conclusions were that: 1)
same aged hybrids of Eucalyptus urophylla from natural or controlled
pollinations did not differ in their crown biomass; 2) log biomass was
reduced in the hybrids from controlled pollination between Eucalyptus
urophylla with Eucalyptus grandis and Eucalyptus urophylla with
descendants of the crossing of Eucalyptus camaldulensis with
Eucalyptus grandis; 3) hybrids of Eucalyptus urophylla from natural
pollination were more productive and more efficient in the absorption
and efficiency of use of N, P, K, Ca and Mg and 4) hybrids of
Eucalyptus urophylla with descendants of the crossing of Eucalyptus
camaldulensis with Eucalyptus grandis are less productive and less
efficient in the absorption and use of N, P, K, Ca and Mg
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