Using Polycarbonate Membranes as Templates for the Preparation of Au Nanostructures for Surface-Enhanced Raman Scattering

Polycarbonate membranes (PCM) of various pores sizes (400, 200, 100 and 50 nm) were used as templates for gold deposition. The electrodeposition from gold ions resulted in the formation of gold nanotubes when large pores size PCMs (400 and 200 nm) were used. On the other hand, gold nanowires were predominant for the PCMs with smaller pores size (100 and 50 nm). Surface-enhanced Raman scattering (SERS) from the probe molecule 4-mercaptopyridine (4-MPy) was obtained from all these nanostructures. The SERS efficiency of the substrates produced using the PC M templates were compared to two commonly used SERS platforms: a roughened gold electrode and gold nanostructures electrodeposited through organized polystyrene spheres (PSS). The SERS signal of the probe molecule increased as the pore diameter of the PCM template decreased. Moreover, the SERS efficiency from the nanostructures produced using 50 nm PCM templates was four and two times better than the signal from the roughened gold electrode and the PSS template, respectively. The SERS substrates prepared using PCM templates were more homogenous over a larger area (ca. 1 cm(2)), presented better spatial and sample to sample reproducibility than the other substrates. These results show that SERS substrates prepared using PCM templates are promising for the fabrication of planar SERS platforms for analytical/bioanalytical applications.

Quenching of excited states of red-pigment zinc protoporphyrin IX by hemin and natural reductors in dry-cured hams

Zinc protoporphyrin IX (ZnPP), the major red pigment in hams dry-cured without nitrates/nitrites, is an efficient photosensitizer, which upon absorption of visible light forms short-lived excited singlet state ((1)ZnPP*) and by intersystem crossing yields the very reactive triplet-excited state ((3)ZnPP*). Using nano-second laser flash photolysis and transient absorption spectroscopy NADH, ascorbic acid, hemin and dehydroascorbic acid were each found to be efficient quenchers of (3)ZnPP*. The deactivation followed, in homogeneous dimethyl sulfoxide (DMSO) or DMSO:water (1:1) solutions, second-order kinetics. The rate constant for ascorbic acid and NADH for reductive quenching of (3)ZnPP* was at 25 A degrees C found to be 7.5 +/- A 0.1 x 10(4) L mol(-1) s(-1) and 6.3 +/- A 0.1 x 10(5) L mol(-1) s(-1), respectively. The polyphenols catechin and quercetin had no effect on (3)ZnPP*. The quenching rate constant for oxidative deactivation of (3)ZnPP* by dehydroascorbic acid and hemin was at 25 A degrees C: 1.6 +/- A 0.1 x 10(5) L mol(-1) s(-1) and 1.47 +/- A 0.1 x 10(9) L mol(-1) s(-1), respectively. Oxidized glutathione did not act as an oxidative quencher for (3)ZnPP*. After photoexcitation of ZnPP to (1)ZnPP*, fluorescence was only found to be quenched by the presence of hemin in a diffusion-controlled reaction. The efficient deactivation of (3)ZnPP* and (1)ZnPP* by the metalloporphyrin (hemin) naturally present in meat may accordingly inherently protect meat proteins and lipids against ZnPP photosensitized oxidation.

Histopathological and histomicrobiological study of root canal therapy medication, comparison of calcium hydroxide versus gutta-percha with zinc oxide/eugenol in the teeth of dogs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Organic and inorganic sources of zinc, copper and selenium in diets for dairy cows: intake, blood metabolic profile, milk yield and composition

The present study was carried out with the objective of evaluating the effects of feeding dairy cows with organic or inorganic sources of zinc (Zn), copper (Cu) and selenium (Se) on blood concentrations of these minerals, blood metabolic profiles, nutrient intake and milk yield and composition. Nineteen Holstein cows were selected and randomly assigned to two groups for receiving organic (n = 9) or inorganic (n = 10) sources of Zn, Cu and Se from 60 days before the expected date of calving to 80 days of lactation. Samples of feed, orts and milk were collected for analysis. Body condition score (BCS) was determined and blood samples were collected for analysis of Zn, Cu and Se concentrations, as well as for metabolic profile. Supplying organic or inorganic sources of Zn, Cu, and Se did not affect dry matter and nutrient intake, blood metabolic profile, milk yield and composition, plasma concentration of these minerals, and BCS or change the BCS in cows from 60 days before the expected date of calving to 80 days of lactation. An effect of time was observed on all feed intake variables, plasma concentrations of Zn and Se, milk yield, milk protein content, BCS and change in BCS.

Biomass and minerals distribution in family of banana 'prata-ana' fertilized with zinc through thinned sprout

In the North of Minas Gerais it is cultivated basically 'Prata-Ana' banana, a cultivar that requires mainly Zn. The possibility of zinc supply, without this nutrient getting in contact with the soil, it is important for the region, since several factors take to the low availability of the element supplied by the soil, as: elevated organic matter content on the surface (from cultural residues); maintenance of high pH of the soil - above 6,00 - as strategy contrary to the proliferation of the causal agent of the Fusarium Wilt; frequent fertilizations with potassium and magnesium that, besides converting the medium into base, they reduce the participation of Zn in the balance cation/anion of the soil, hindering the absortion of this micronutrient by the plant. For determining the distribution of biomass and minerals in the Prata-Ana" banana, cultivated under irrigation in the North of Minas Gerais, when the zinc was supplied through thinned sprout, an experiment was carried out in the Irrigated Perimeter of Jaiba. The plants were fertilized with 0,00; 1,66 and 3,33 g.family-(1) of Zn, through thinned sprout. One month after the fertilizations from October 2007 and February 2008, the production of fresh mass (FM) and dry mass (DM) were evaluated, the contents and meanings of minerals in all the bananas "family" bodies composed by mother-plant with bunch + tall daughter-plant + granddaughter-plant. The doses of Zn did not influence on the production of FM and DM of the plants in the first evaluation, while in the second evaluation positive effect of the treatment was observed just for MF accumulated in the inferior leaves, in the portions of the medium third and inferior of the pseudostem, and in the mother-plant's rhizome. As much the content as the accumulation of nutrients in the mother-plants presented the following decreasing order: K > N > Ca > Mg > P > S > Fe > Zn > B > Cu. The Zn contents were affected by the dose of that micronutrient in the most of the studied situations. The zinc supplied through thinned sprout increased in the mother-plant, and then it was redistributed in the banana's "family".

Egg quality during storage and deposition of minerals in eggs from quails fed diets supplemented with organic selenium, zinc and manganese

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Response of wheat to foliar application of zinc

Wheat is grown in Brazil, mostly in no-till, a system in which the zinc can become potentially deficient, due to excessive application of acidity corrective and phosphate fertilizers in surface and, or at shallow depths. This study aimed to evaluate the effect of foliar application of zinc in agronomic characteristics and yield of wheat. The experimental design was randomized blocks with five replications. Treatments consisted of four doses of zinc (0, 54, 108 and 216g ha(-1) Zn), divided into two foliar applications, the first at tillering (18 days after plant emergence) and the second at the boot stage (65 days after emergence). Foliar application of zinc increased the number of fertile tillers and yield of wheat, however, have little effect on the agronomic characteristics of no-tilled crop with high nutrient content in soil.

Pyrolysis and auto-gasification of black liquor in presence of ZnO: An integrated process for Zn/ZnO nanostructure production and bioenergy generation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Preparation and structural characterization of vulcanized natural rubber nanocomposites containing nickel-zinc ferrite nanopowders

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Optical properties of polydisperse submicrometer aggregates of sulfur-containing zinc oxide consisting of spherical nanocrystallites

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Surface-enhanced raman scattering: metal nanostructures coated with langmuir-blodgett films

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Structural and Electric-Optical Properties of Zinc Phthalocyanine Evaporated Thin Films: Temperature and Thickness Effects

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Altered plasma response to zinc and iron tolerance test after Roux-en-Y gastric bypass

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Splice variants of the human ZC3H14 gene generate multiple isoforms of a zinc finger polyadenosine RNA binding protein

The human ZC3H14 gene encodes an evolutionarily conserved Cys(3)His zinc finger protein that binds specifically to polyadenosine RNA and is thus postulated to modulate post-transcriptional gene expression. Expressed sequence tag (EST) data predicts multiple splice variants of both human and mouse ZC3H14. Analysis of ZC3H14 expression in both human cell lines and mouse tissues confirms the presence of multiple alternatively spliced transcripts. Although all of these transcripts encode protein isoforms that contain the conserved C-terminal zinc finger domain, suggesting that they could all bind to polyadenosine RNA, they differ in other functionally important domains. Most of the alternative transcripts encode closely related proteins (termed isoforms 1, 2. 3, and 3short) that differ primarily in the inclusion of three small exons, 9, 10, and 11, resulting in predicted protein isoforms ranging from 82 to 64 kDa. Each of these closely related isoforms contains predicted classical nuclear localization signals (cNLS) within exons 7 and 11. Consistent with the presence of these putative nuclear targeting signals, these ZC3H14 isoforms are all localized to the nucleus. In contrast, an additional transcript encodes a smaller protein (34 kDa) with an alternative first exon (isoform, 4). Consistent with the absence of the predicted cNLS motifs located in exons 7 and 11, ZC3H14 isoform 4 is localized to the cytoplasm. Both EST data and experimental data suggest that this variant is enriched in testes and brain. Using an antibody that detects endogenous ZC3H14 isoforms 1-3 reveals localization of these isoforms to nuclear speckles. These speckles co-localize with the splicing factor, SC35, suggesting a role for nuclear ZC3H14 in mRNA processing. Taken together, these results demonstrate that multiple transcripts encoding several ZC3H14 isoforms exist in vivo. Both nuclear and cytoplasmic ZC3H14 isoforms could have distinct effects on gene expression mediated by the common Cys(3)His zinc finger polyadenosine RNA binding domain. (C) 2009 Elsevier B.V. All rights reserved.