Improved functionalization of oleic acid-coated iron oxide nanoparticles for biomedical applications

Superparamagnetic iron oxide nanoparticles can providemultiple benefits for biomedical applications in aqueous environments such asmagnetic separation or magnetic resonance imaging. To increase the colloidal stability and allow subsequent reactions, the introduction of hydrophilic functional groups onto the particles’ surface is essential. During this process, the original coating is exchanged by preferably covalently bonded ligands such as trialkoxysilanes. The duration of the silane exchange reaction, which commonly takes more than 24 h, is an important drawback for this approach. In this paper, we present a novel method, which introduces ultrasonication as an energy source to dramatically accelerate this process, resulting in high-quality waterdispersible nanoparticles around 10 nmin size. To prove the generic character, different functional groups were introduced on the surface including polyethylene glycol chains, carboxylic acid, amine, and thiol groups. Their colloidal stability in various aqueous buffer solutions as well as human plasma and serum was investigated to allow implementation in biomedical and sensing applications.status: publishe

Banal interculturalism. Latin Americans in Elephant & Castle

This paper discusses banal interculturalism as produced in an interview situation with migrants of Latin American background in London. Banal interculturalism emerges within discursive semiotic processes that allow the participants to display their (cultural) knowledge about co-ethnics and their practices, to position themselves in opposition to the ‘others’ within diaspora, and to justify their, typically negative, views towards other migrants. Sources of that knowledge can be experiential, though in most cases consist of hearsay evidence. This notion may assist intercultural communication scholars in understanding how intra-group relations are conceived and the consequences for migrants of the discourses they themselves spread within the wider group

Rastreabilidade da farinha de carne e ossos bovinos em ovos de poedeiras comerciais pela técnica dos isótopos estáveis do carbono e nitrogênio Traceability of bovine meat and bones meal in eggs of commercial laying hens through carbon and nitrogen stable isotopes technique

Objetivou-se com este estudo rastrear a inclusão de farinha de carne e ossos bovinos em dietas para poedeiras comerciais, por meio da análise dos ovos e de suas frações (gema e albúmen), pela técnica dos isótopos estáveis do carbono e nitrogênio e avaliar o índice analítico mínimo detectável. Foram utilizadas 240 galinhas poedeiras da linhagem Shaver White de 73 semanas de idade, distribuídas em delineamento inteiramente casualizado, com cinco tratamentos e seis repetições. Foram avaliados cinco níveis de inclusão (0; 1,5; 3,0; 4,5 e 6,0%) de farinha de carne e ossos bovinos em uma dieta à base de milho e farelo de soja. No 35º dia, foram tomados aleatoriamente 24 ovos por tratamento: 12 serviram para amostragem de gema e albúmen e os outros 12 para amostragem do ovo (gema + albúmen). Os resultados isotópicos foram submetidos à análise multivariada de variância e, a partir das matrizes de erro, com 95% de confiança, foram determinadas elipses para identificar as diferenças entre os resultados obtidos com o fornecimento das dietas experimentais e a dieta controle, sem farinha de carne e ossos bovinos. No ovo e na gema, a partir do par isotópico da dieta com 3,0% de farinha de carne e ossos, houve diferenciação do par do tratamento controle, enquanto, no albúmen, a diferenciação ocorreu a partir do nível de 1,5% de farinha de carne e ossos bovinos na dieta. Pela técnica dos isótopos estáveis, é possível rastrear o uso de farinha de carne e ossos bovinos na alimentação de poedeiras; no albúmen, o nível mínimo de inclusão detectável é de 1,5% e, no ovo e na gema, 3,0%.<br>The objective of this study was to trace the inclusion of bovine meat and bones meal in diets of laying hens analyzing eggs and theirs fractions (yolk and albumen), by carbon and nitrogen stable isotopes, as well as to evaluate the detectable analytical minimal index. Two hundred and forty (240) Shaver White laying hens aging 73 weeks were distributed in a completely randomized design, with five treatments and six replicates. Five increasing levels (0; 1.5; 3.0; 4.5 and 6.0%) of bovine meat and bones meal in a diet based on corn and soybean meal were evaluated. On the 35th day, 24 eggs per treatment were randomly collected, twelve for yolk and albumen sampling and another twelve for egg (yolk + albumen) sampling. The isotopic results were analyzed in a multivariate analysis of variance. Through an error matrix (95% confidence) the ellipses were determined to identify the differences between results obtained with supply of experimental diets and control diet, without 3% bovine meat and bones meal. In egg and yolk, from the isotopes pair of the diet with 3% bovine meat and bones meal, there was differentiation in the pair of the control treatment, whereas in the albumen it was possible to detect the 1.5 bovine meat and bones meal. The stable isotopes technique is able to trace the use of bovine meat and bones meal in laying hens feed; the minimal traceable level of inclusion is 1.5% in the albumen and 3.0% in the egg and yolk

The traceability of animal meals in layer diets as detected by stable carbon and nitrogen isotope analyses of eggs

The aim of this study was to trace the inclusion of animal meals in layer diets by analyzing eggs and their fractions (yolk and albumen) using the technique of carbon and nitrogen isotopes. Two-hundred and eighty-eight (288) 73-week-old Shaver White layers, never fed animal ingredients, were randomly distributed in six treatments with six replicates each. The treatments were: control - corn and soybean meal based diet and five other experimental diets including bovine meat and bone meal (MBM); poultry offal meal (POM); feather meal (FM); feather meal and poultry offal meal (OFM), and poultry offal meal, feather meal, and meat and bone meal (MBOFM). The isotopic results were submitted to multivariate analysis of variance. Ellipses were determined through an error matrix (95% confidence) to identify differences between treatments and the control group. In the albumen and yolk of all experimental treatments were significantly different from the control diet (p < 0.05). In summary, the stable isotope technique is able to trace the animal meals included in layer feeds in the final product under these experimental conditions