Optical properties of zirconium oxynitride films: the effect of composition, electronic and crystalline structures

tThis work is devoted to the investigation of zirconium oxynitride (ZrOxNy) films with varied opticalresponses prompted by the variations in their compositional and structural properties. The films wereprepared by dc reactive magnetron sputtering of Zr, using Ar and a reactive gas mixture of N2+ O2(17:3).The colour of the films changed from metallic-like, very bright yellow-pale and golden yellow, for low gasflows to red-brownish for intermediate gas flows. Associated to this colour change there was a significantdecrease of brightness. With further increase of the reactive gas flow, the colour of the samples changedfrom red-brownish to dark blue or even to interference colourations. The variations in composition dis-closed the existence of four different zones, which were found to be closely related with the variationsin the crystalline structure. XRD analysis revealed the change from a B1 NaCl face-centred cubic zirco-nium nitride-type phase for films prepared with low reactive gas flows, towards a poorly crystallizedover-stoichiometric nitride phase, which may be similar to that of Zr3N4with some probable oxygeninclusions within nitrogen positions, for films prepared with intermediate reactive gas flows. For highreactive gas flows, the films developed an oxynitride-type phase, similar to that of -Zr2ON2with someoxygen atoms occupying some of the nitrogen positions, evolving to a ZrO2monoclinic type structurewithin the zone where films were prepared with relatively high reactive gas flows. The analysis carriedout by reflected electron energy loss spectroscopy (REELS) revealed a continuous depopulation of thed-band and an opening of an energy gap between the valence band (2p) and the Fermi level close to 5 eV.The ZrN-based coatings (zone I and II) presented intrinsic colourations, with a decrease in brightness anda colour change from bright yellow to golden yellow, red brownish and dark blue. Associated to thesechanges, there was also a shift of the reflectivity minimum to lower energies, with the increase of thenon-metallic content. The samples lying in the two last zones (zone III, oxynitride and zone IV, oxide films)revealed a typical semi-transparent-optical behaviour showing interference-like colourations only dueto the complete depopulation of the d band at the Fermi level. The samples lying in these zones presentedalso an increase of the optical bandgap from 2 to 3.6 eV.

Postpartum depression in Recife - Brazil: prevalence and association with bio-socio-demographic factors

OBJECTIVE:To use a semi-structured interview to detect depression in postpartum women according to the criteria proposed by the DSM in child health care clinics in the city of Recife, together with the proper association of this disorder to bio-socio-demographic data. METHODS: The study used a cross-section method and contained a convenience sample of 400 women that were between 2 and 26 weeks of postpartum in child health care clinics. A bio-socio-demographic questionnaire and the Portuguese version of the Structured Clinical Interview for DSM-IV Axis I Disorders were used. RESULTS: Twenty nine of the mothers (7.2%) were diagnosed as suffering from postpartum depression. Women with a past history of psychiatric disorders, a family history of psychiatric disorder and some sort of clinical complication presented a higher prevalence of depression. The same happened to those with a past history of spontaneous abortion, those who had a transpelvic birth and those over 8 weeks of puerperium. CONCLUSION: The rate of postpartum depression in this sample, 7.2%, was lower than that reported by other Brazilian studies. It probably occurred because the other researchers used screening scales to assess this estimate instead of a clinical interview.

A bio-inspired computational model for motion detection

Tese de Doutoramento (Programa Doutoral em Engenharia Biomédica)

HPV DNA testing with cytology triage in cervical cancer screening: Influence of revealing HPV infection status

BACKGROUND: Knowledge of cervical human papillomavirus (HPV) status might influence a cytotechnician's assessment of cellular abnormalities. The authors compared original cytotechnicians' Papanicolaou (Pap) readings for which HPV status was concealed with Pap rereads for which HPV status was revealed separately for 3 screening populations. METHODS: Previously collected cervical Pap smears and clinical data were obtained from the Canadian Cervical Cancer Screening Trial (study A), the Democratic Republic of Congo Community-Based Screening Study (study B), and the Brazilian Investigation into Nutrition and Cervical Cancer Prevention (study C). Smears were reread with knowledge of HPV status for all HPV-positive women as well as a sample of HPV-negative women. Diagnostic performance of Pap cytology was compared between original readings and rereads. RESULTS: A total of 1767 Pap tests were reread. Among 915 rereads for HPV-positive women, the contrast between "revealed" and "concealed" Pap readings demonstrated revisions from negative to positive results for 109 women (cutoff was atypical squamous cells of undetermined significance or worse) and 124 women (cutoff was low-grade squamous intraepithelial lesions [LSIL] or worse). For a disease threshold of cervical intraepithelial neoplasia of grade 2 or worse, specificity significantly declined at the atypical squamous cells of undetermined significance cutoff for studies A (86.6% to 75.3%) and C (42.5% to 15.5%), and at the LSIL cutoff for study C (61.9% to 37.6%). Sensitivity remained nearly unchanged between readings, except in study C, in which reread performance was superior (91.3% vs 71.9% for the LSIL cutoff). CONCLUSIONS: A reduction in the diagnostic accuracy of Pap cytology was observed when revealing patients' cervical HPV status, possibly due to a heightened awareness of potential abnormalities, which led to more false-positive results. Cancer (Cancer Cytopathol) 2015. (c) 2015 American Cancer Society.

Fueling the bio-economy: european culture collections and microbiology education and training

A survey of European Microbial Biological Resource Centers and their users provided an overview on Microbiology education and training. The results identified future increases in demand despite several shortcomings and gaps in the current offer. Urgent adjustments are needed to match users' needs, integrate innovative programs, and adopt new technologies.

Status de fragilidade entre idosos com indicativo de depressão segundo o sexo

Objetivos : Descrever as variáveis socioeconômicas de idosos com indicativo de depressão segundo o sexo, verificar a associação entre o status de fragilidade e o sexo, e descrever o componente do fenótipo de fragilidade mais impactado entre os idosos com indicativo de depressão pré-frágeis e frágeis. Métodos Estudo observacional, transversal e analítico, conduzido com 418 idosos com indicativo de depressão residentes no município de Uberaba, MG. Utilizaram-se a Escala de Depressão Geriátrica Abreviada e o Fenótipo de Fragilidade de Fried. Foram utilizados análise descritiva e o teste Qui-quadrado (p < 0,05). Resultados Verificou-se que, entre os idosos com indicativo de depressão, 27,8% eram frágeis e 51,7%, pré-frágeis. O status de fragilidade não esteve associado ao sexo (p = 0,910). Dentre os pré-frágeis, os componentes do fenótipo mais impactados foram o autorrelato de exaustão/fadiga para as mulheres e diminuição da força muscular para os homens. Nos frágeis, prevaleceu a diminuição da força muscular para ambos os sexos. Conclusão Mediante os achados deste estudo, conclui-se que, embora não tenha ocorrido associação entre a síndrome de fragilidade e o sexo, a identificação dos componentes do fenótipo de fragilidade mais impactados pode favorecer o atendimento multiprofissional, considerando as especificidades dos grupos. O diagnóstico precoce contribui para o estabelecimento de condutas e prevenção de agravos.

La carte postale et la représentation des espaces public et intime

La carte postale est un kaléidoscope de vues, d’ornements et de couleurs, qui consacre un tout petit espace au message. C’est à la photographie et aux procédés de reproduction photomécaniques que revient le mérite d’avoir industrialisé la production de la carte postale. Et ce sont les clichés de villes, avec leurs monuments et leurs paysages, qui confèrent à la carte postale son statut de moyen de communication de masse et qui lui concèdent une affinité avec l’industrie du tourisme. La carte postale s’est ainsi emparée de l’ambition photographique de reproduire le monde, s’alliant aux « besoins de l’exploration, des expéditions et des relevés topographiques » du médium photographique à ses débuts. Ayant comme point de départ la carte postale, notre objectif est de montrer les conséquences culturelles de la révolution optique, commencée au milieu du XIXe siècle, avec l’invention de l’appareil photo, et consumée dans la seconde moitié du XXe siècle, avec l’apparition de l’ordinateur. En effet, depuis l’apparition de l’appareil photographique et des cartes postales jusqu’au flux de pixels de Google Images et aux images satellite de Google Earth, un entrelacement de territoire, puissance et technique a été mis en oeuvre, la terre devenant, en conséquence, de plus en plus auscultée par les appareils de vision, ce qui impacte sur la perception de l’espace. Nous espérons pouvoir montrer avec cette étude que la lettre traditionnelle est à l’email ce que la carte postale est au post que l’on publie dans un blog ou dans des réseaux comme Facebook et Twitter. À notre sens, les cartes postales correspondent à l’ouverture maximale du système postal moderne, qui d’universel devient dépendant et partie intégrante des réseaux télématiques d’envoi. Par elles sont annoncés, en effet, la vitesse de transmission de l’information, la brièveté de la parole et l’hégémonie de la dimension imagétique du message, et pour finir, l’embarras provoqué par la fusion de l’espace public avec l’espace privé.

New bio-strategies for ochratoxin A detoxification using lactic acid bacteria

The occurrence of mycotoxigenic moulds such as Aspergillus, Penicillium and Fusarium in food and feed has an important impact on public health, by the appearance of acute and chronic mycotoxicoses in humans and animals, which is more severe in the developing countries due to lack of food security, poverty and malnutrition. This mould contamination also constitutes a major economic problem due the lost of crop production. A great variety of filamentous fungi is able to produce highly toxic secondary metabolites known as mycotoxins. Most of the mycotoxins are carcinogenic, mutagenic, neurotoxic and immunosuppressive, being ochratoxin A (OTA) one of the most important. OTA is toxic to animals and humans, mainly due to its nephrotoxic properties. Several approaches have been developed for decontamination of mycotoxins in foods, such as, prevention of contamination, biodegradation of mycotoxins-containing food and feed with microorganisms or enzymes and inhibition or absorption of mycotoxin content of consumed food into the digestive tract. Some group of Gram-positive bacteria named lactic acid bacteria (LAB) are able to release some molecules that can influence the mould growth, improving the shelf life of many fermented products and reducing health risks due to exposure to mycotoxins. Some LAB are capable of mycotoxin detoxification. Recently our group was the first to describe the ability of LAB strains to biodegrade OTA, more specifically, Pediococcus parvulus strains isolated from Douro wines. The pathway of this biodegradation was identified previously in other microorganisms. OTA can be degraded through the hydrolysis of the amide bond that links the L-β-phenylalanine molecule to the ochratoxin alpha (OTα) a non toxic compound. It is known that some peptidases from different origins can mediate the hydrolysis reaction like, carboxypeptidase A an enzyme from the bovine pancreas, a commercial lipase and several commercial proteases. So, we wanted to have a better understanding of this OTA degradation process when LAB are involved and identify which molecules where present in this process. For achieving our aim we used some bioinformatics tools (BLAST, CLUSTALX2, CLC Sequence Viewer 7, Finch TV). We also designed specific primers and realized gene specific PCR. The template DNA used came from LAB strains samples of our previous work, and other DNA LAB strains isolated from elderberry fruit, silage, milk and sausages. Through the employment of bioinformatics tools it was possible to identify several proteins belonging to the carboxypeptidase family that participate in the process of OTA degradation, such as serine type D-Ala-D-Ala carboxypeptidase and membrane carboxypeptidase. In conclusions, this work has identified carboxypeptidase proteins being one of the molecules present in the OTA degradation process when LAB are involved.

Novas bio-estratégias para a destoxificação de ocratoxina A utilizando bactérias do ácido láctico

A ocorrência de bolores micotoxigénicos pertencentes aos géneros Aspergillus, Penicillium e Fusarium em alimentos para consumo Humano e animal, tem um impacto importante sobre a saúde pública e constitui também um importante problema económico. Isto é devido à síntese por este tipo de fungos filamentosos de metabolitos altamente tóxicos conhecidos como micotoxinas. A maioria das micotoxinas são substâncias cancerígenas, mutagénicas, neurotóxicas e imunossupressoras, sendo a ocratoxina A (OTA) uma das mais importantes. A OTA é uma micotoxina, tóxica para os animais e Humanos principalmente devido às suas propriedades nefrotóxicas. Alguns grupos de bactérias gram positivas nomeadamente as bactérias do ácido láctico (BAL) são capazes de controlar o crescimento de fungos, melhorando e aumentando a vida útil de muitos produtos fermentados e, assim, reduzir os riscos para a saúde provocados pela exposição às micotoxinas. Algumas BAL são, também, capazes de destoxificar certas micotoxinas. Em trabalhos anteriores do nosso grupo foi observada a biodegradação da OTA por estirpes de Pediococcus parvulus isoladas de vinhos do Douro. Assim, com este trabalho, pretendeu-se compreender com maior detalhe o processo de biodegradação da OTA pelas referidas estirpes e identificar quais as enzimas que estão associadas à sua biodegradação. Para atingir este objetivo utilizaram-se algumas ferramentas ioinformáticas (BLAST, CLUSTALX2, CLC Sequence Viewer 7, Finch TV), desenharam-se primers específicos e realizaram-se PCR específicos para os genes envolvidos. Através da utilização de ferramentas de bioinformática, foi possível identificar várias proteínas que pertencem à família das carboxipeptidases e que podem eventualmente participar no processo da degradação da OTA, tais como D-Ala-D-Ala carboxipeptidase serínica e carboxipeptidase membranar. Estas BAL podem desempenhar um papel importante na destoxificação da OTA, sendo as carboxipeptidases uma das enzimas envolvidas na sua biodegradação.

A comunicação online: a página Web como o BIO Empresarial: estratégias de comunicação visual e web design

Dissertação de mestrado em Ciências da Comunicação (área de especialização em Audiovisuais e Multimédia)

Vermiculite bio-barriers for Cu and Zn remediation: an eco-friendly approach for freshwater and sediments protection

The increase in heavy metal contamination in freshwater systems causes serious environmental problems in most industrialized countries, and the effort to find ecofriendly techniques for reducing water and sediment contamination is fundamental for environmental protection. Permeable barriers made of natural clays can be used as low-cost and eco-friendly materials for adsorbing heavy metals from water solution and thus reducing the sediment contamination. This study discusses the application of permeable barriers made of vermiculite clay for heavy metals remediation at the interface between water and sediments and investigates the possibility to increase their efficiency by loading the vermiculite surface with a microbial biofilm of Pseudomonas putida, which is well known to be a heavy metal accumulator. Some batch assays were performed to verify the uptake capacity of two systems and their adsorption kinetics, and the results indicated that the vermiculite bio-barrier system had a higher removal capacity than the vermiculite barrier (?34.4 and 22.8 % for Cu and Zn, respectively). Moreover, the presence of P. putida biofilm strongly contributed to fasten the kinetics of metals adsorption onto vermiculite sheets. In open-system conditions, the presence of a vermiculite barrier at the interface between water and sediment could reduce the sediment contamination up to 20 and 23 % for Cu and Zn, respectively, highlighting the efficiency of these eco-friendly materials for environmental applications. Nevertheless, the contribution of microbial biofilm in open-system setup should be optimized, and some important considerations about biofilm attachment in a continuous-flow system have been discussed.

Development of active bio-based multilayer systems: encapsulation of cinnamaldehyde and their physicochemical characterization

[Excerpt] In this work, different multilayer structures, using a polyhydroxybutyrate-co-valerate film with a valerate content of 8% (PHBV8) as support, were developed aiming the development of active bio-based multilayer systems. An interlayer based on zein nanofibers with and without cinnamaldehyde were electrospun in the PHBV8 film and three multilayer systems were developed: 1) without an outer layer; 2) using a PHBV8 film as outer layer; and 3) using an alginate-based film as outer layer. Their physico-chemical properties were evaluated through: water vapour and oxygen permeabilities and colour measurements, Fourier Transform Infrared Spectroscopy (FTIR) and thermal analyses. Results showed that the presence of different outer layers affected the water vapour permeability and transparency of the multilayer films. (...)

In-line rheo-optical microstructural characterization of complex polymer systems

Tese de Doutoramento em Ciência e Engenharia de Polímeros e Compósitos.

Minería de Datos en Bio-Ciencias

El campo de las Bio-Ciencias está en pleno desarrollo y expansión. La variedad de tecnologías disponibles y aplicaciones están generando una cantidad abrumadora de datos que necesitan de protocolos, conceptos y métodos que permitan un análisis uniforme y asequible. Otra característica distintiva de estos ámbitos es su condición multidisciplinaria, donde interactúan (y cada vez más) disciplinas como la biología, la matemática, la estadística, la informática, la inteligencia artificial, etc. por lo que cualquier esfuerzo tendiente a aumentar el nivel de comunicación y entendimiento entre las disciplinas redundará en beneficios. La Minería de Datos, concepto que aglutina una variedad de metodologías analíticas, proporciona un marco conceptual y metodológico para el abordaje del análisis de datos y señales de distintas disciplinas. Sin embargo, cada campo de aplicación presenta desafíos específicos que deben ser abordados particularmente desde la racionalización de conceptos específicos del ámbito. La multidisiplinaridad es particularmente importante en aplicaciones biomédicas y biotecnológicas, donde se modelan fenómenos biológicos y se desarrollan métodos analíticos para generar nuevas estrategias diagnósticas, predictivas a partir de los datos recogidos. En este proyecto se integrarán las experiencias y criterios de distintas disciplinas que están involucradas en el desarrollo experimental en bio-ciencias, desde la biología molecular y la bioingeniería hasta la bioinformática y la estadística. La finalidad es elaborar protocolos que permitan extraer conocimiento en problemas biotecnológicos (particularmente experimentos genómicos) que se basan en la investigación sólida de los procedimientos estadísticos / bioinformáticos relevante para el manejo de datos experimentales. EL objetivo general de este proyecto es contribuir a la instauración de un Proceso Unificado de Análisis en Biotecnología generando conocimiento que permita el desarrollo de nuevas metodologías de análisis, con especial énfasis en métodos lineales y no-lineales de clasificación / predicción. La comprensión y estandarización de los requerimientos y etapas de experimentos en bio-ciencias es imprescindible para el éxito de proyectos biotecnológicos / biomédicos.

Situación poblacional del cóndor andino (Vultur gryphus) en las sierras de Córdoba. Population status of the Andean Condor (Vultur gryphus) in Sierras de Córdoba mountain range.

Existe una clara necesidad de obtener información científica y comprensible sobre la distribución actual, abundancia y el estado de conservación del cóndor andino (Vultur gryphus) en Córdoba. Las justificaciones de ello incluyen: 1) la información disponible es muy limitada y fragmentada, y es insuficiente para las decisiones de manejo, 2) el aparente aislamiento de la población de cóndor andino de Córdoba respecto a la principal distribución de la especie a lo largo de los Andes sudamericanos, hecho que merece especial consideración, 3) indicaciones de que la especie muestra signos de declinación a lo largo de su rango de distribución, y 4) el valor de la especie como ave carismática y componente clave de atracción turística en la provincia de Córdoba. Esta propuesta pretende llenar el vacío de información existente mediante los siguientes objetivos específicos: 1) relevar la distribución del cóndor andino en Córdoba, 2) evaluar el tamaño poblacional de la especie a través de relevamientos en sus colonias no reproductivas, y 3) obtener la información disponible de la literatura publicada, material arqueológico y de informantes calificados. Los métodos incluyen: a) relevamientos sistemáticos a campo, b) conteos poblacionales en aquellos sitios identificados como colonias no reproductivas de la especie, c) revisión bibliográfica, y d) entrevistas a informantes selectos como ornitólogos, guías turísticos, pobladores rurales locales clave, etc. La información obtenida proveerá una línea de base de la situación actual del cóndor andino en Córdoba, como así también los criterios necesarios y la metodología para un monitoreo continuado de la especie en el territorio provincial.