RESUMO
Um dos desafios das mudanças e evoluções das tecnologias de informação e comunicação (TIC) em corporações é a preservação das informações digitais. Entre as corporações com grande geração de informações digitais estão as universidades. Neste artigo, é apresentada uma estratégia para se elaborar uma política de preservação digital no bojo de uma política arquivística direcionada para a manutenção da autenticidade dos documentos de arquivo. O objetivo é expor um modelo para elaboração de políticas de preservação digital de documentos de arquivo por instituições de ensino superior (IES), com os elementos que devem compô-las, a partir da literatura estudada e da política elaborada e aprovada na Universidade Estadual Paulista (Unesp). São apresentados os conceitos relacionados à política arquivística para a preservação digital de documentos de arquivo, sua definição, seus aspectos e elementos. Concluiu-se que o modelo pode ser adaptado para outros objetos digitais, bem como para outras instituições.
One of the challenges of the changes and evolutions of the information and communication technology (ICT) in corporations is the preservation of digital information. The universities are among the corporations with a large generation of digital information. This article presents a strategy for the elaboration of a digital preservation policy, in the context of an archival policy which is aimed at maintaining the authenticity of archival documents. The objective of this article is to present a model so that the higher education institutions could making policies for the digital preservation of their archival documents, showing the elements that must compose each one, based on the studied literature and on the policy elaborated in Unesp and which was officially approved by that institution. Concepts related to archival policy for the digital preservation of archival documents, their definition, aspects and elements are presented here. It was concluded that the model can be adapted for other digital objects, as well as for other institutions.
Uno de los desafíos de los cambios y la evolución de las TIC en las corporaciones es la preservación de informaciones digitales. Entre las corporaciones con una gran generación de información digital se encuentran las universidades. En este artículo, se presenta una estrategia para elaborar una política de preservación digital, en medio de una política de archivo dirigida a mantener la autenticidad de los documentos de archivo. El objetivo del artículo es presentar un modelo para la elaboración de políticas de preservación digital de documentos de archivo por instituciones de enseñanza superior, con los elementos que deben componerlas, basado en la literatura estudiada y en la política desarrollada y aprobada en la Unesp. Se presentan conceptos relacionados con la política de archivo para la preservación digital de documentos de archivo, su definición, aspectos y elementos. Se concluyó que este modelo puede adaptarse para otros objetos digitales, así como para otras instituciones.
Assuntos
Humanos , Registros , Tecnologia da Informação , Políticas , Arquivamento , Cultura Organizacional , Armazenamento e Recuperação da Informação , Administração das Tecnologias da InformaçãoRESUMO
We report a new type of magnetic nanofluids, which is based on a hybrid composite of nanodiamond and nickel (ND-Ni) nanoparticles. We prepared the nanoparticles by an in-situ method involving the dispersion of caboxylated nanodiamond (c-ND) nanoparticles in ethylene glycol (EG) followed by mixing of nickel chloride and, at the reaction temperature of 140°C, the use of sodium borohydrate as the reducing agent to form the ND-Ni nanoparticles. We performed their detailed surface and magnetic characterization by X-ray diffraction, micro-Raman, high-resolution transmission electron microscopy, and vibrating sample magnetometer. We prepared stable magnetic nanofluids by dispersing ND-Ni nanoparticles in a mixture of water and EG; we conducted measurements to determine the thermal conductivity and viscosity of the nanofluid with different nanoparticles loadings. The nanofluid for a 3.03% wt. of ND-Ni nanoparticles dispersed in water and EG exhibits a maximum thermal conductivity enhancement of 21% and 13%, respectively. For the same particle loading of 3.03% wt., the viscosity enhancement is 2-fold and 1.5-fold for water and EG nanofluids. This particular magnetic nanofluid, beyond its obvious usage in heat transfer equipment, may find potential applications in such diverse fields as optics and magnetic resonance imaging.
RESUMO
Nano-GO is a graphene derivative with a 2D atomic layer of sp² bonded carbon atoms in hexagonal conformation together with sp³ domains with carbon atoms linked to oxygen functional groups. The supremacy of nano-GO resides essentially in its own intrinsic chemical and physical structure, which confers an extraordinary chemical versatility, high aspect ratio and unusual physical properties. The chemical versatility of nano-GO arises from the oxygen functional groups on the carbon structure that make possible its relatively easy functionalization, under mild conditions, with organic molecules or biological structures in covalent or non-covalent linkage. The synergistic effects resulting from the assembly of well-defined structures at nano-GO surface, in addition to its intrinsic optical, mechanical and electronic properties, allow the development of new multifunctional hybrid materials with a high potential in multimodal cancer therapy. Herein, a comprehensive review of the fundamental properties of nano-GO requirements for cancer therapy and the first developments of nano-GO as a platform for this purpose is presented.
Assuntos
Grafite/química , Nanopartículas/química , Animais , Antineoplásicos/administração & dosagem , Complexos de Coordenação/química , Portadores de Fármacos/química , Grafite/uso terapêutico , Humanos , Lipossomos/química , Lipossomos/uso terapêutico , Nanopartículas/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Óxidos/química , Polietilenoglicóis/química , RadiografiaRESUMO
In this paper, we report a novel method for the synthesis of L-Lysine (lys) amino acid coated maghemite (gamma-Fe2O3) magnetic nanoparticles (MNPs). The facile and cost effective method permitted preparation of the high-quality superparamagnetic gamma-Fe2O3 MNPs with hydrophilic and biocompatible nature. For this work, first we synthesized magnetite phase Fe3O4/lys by wet chemical method and oxidized to y-Fe2O3 in controlled oxidizing environment, as evidenced by XRD and VSM magnetometry. The crystallite size and magnetization of gamma-Fe2O3/lys MNPs was found to be 14.5 nm, 40.6 emu/gm respectively. The surface functionalization by L-lysine amino acid and metal-ligand bonding was also confirmed by FTIR spectroscopy. The hydrodynamic diameter, colloidal stability and surface charge on MNPs were characterized by DLS and zeta potential analyser.
Assuntos
Aminoácidos/síntese química , Materiais Biocompatíveis , Compostos Férricos/química , Lisina/química , Magnetismo , Nanopartículas Metálicas , Aminoácidos/química , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios XRESUMO
As interest in using carbon nanotubes for developing biologically compatible systems continues to grow, biological inspiration is stimulating new directions for in vivo approaches. The ability to integrate nanotechnology-based systems in the body will provide greater successes if the implanted material is made to mimic elements of the biological milieu especially through tuning physical and chemical characteristics. Here, we demonstrate the highly successful capacity for in vivo implantation of a new carbon nanotube-based composite that is, itself, integrated with a hydroxyapatite-polymethyl methacrylate to create a nanocomposite. The success of this approach is grounded in finely tailoring the physical and chemical properties of this composite for the critical demands of biological integration. This is accomplished through controlling the surface modification scheme, which affects the interactions between carbon nanotubes and the hydroxyapatite-polymethyl methacrylate. Furthermore, we carefully examine cellular response with respect to adhesion and proliferation to examine in vitro compatibility capacity. Our results indicate that this new composite accelerates cell maturation through providing a mechanically competent bone matrix; this likely facilitates osteointegration in vivo. We believe that these results will have applications in a diversity of areas including carbon nanotube, regeneration, chemistry, and engineering research.