Programmable Dna Delivery To Cells Using Bioreducible Layer-By-Layer (lbl) Polyelectrolyte Thin Films

Bioreducible, layer-by-layer (LbL) polyelectrolyte films show great promise for use in biomedical implant and gene-delivery applications. These nanometer-scale thin films can easily be coated onto a variety of implantable surfaces or devices. To achieve proof of concept, HEK-293, NIH/3T3, RAW, and MC3T3 cells were transfected using plasmid DNA with the green fluorescent protein reporter gene (GFP-DNA). In order to optimize transfection, a number of polyelectrolytes and biological components were systematically incorporated into the two similar basic LbL structures. Based on our previous degradation assays, it is shown that cellular interactions in vitro can break down the layers of the thin films on substrates, allowing for DNA and future therapeutics to be released gradually over periods of time, or in bulk, depending on modifications to the structure and composition. Using an efficient in vitro polyplex testing method, different bioreducible polycations were examined in order to select a polyelectrolyte with high transfection. Following polyplex testing, thin films were made using the layer-by-layer dip coating method and cells were cultured on the subsequent films in an in vitro setting. The basic LbL structure comprises alternating polycation, GFP-DNA, and polyethylenimine (PEI) as an effective barrier layer. In vitro testing for transfection was monitored using fluorescence microscopy over 10 days, among other evaluation methods. Through these studies, transfection was achieved. This lays the groundwork for future studies using bioreducible thin films to deliver DNA, small molecules, or other therapeutics to cells

Zooplankton community responses to Ocean Acidification

Ocean acidification is affecting marine ecosystems directly through changes in pH, as well as indirectly, via trophic pathways. Thus, to evaluate impacts of ocean acidification on marine communities it is necessary to consider the potential pCO2 effects on population dynamics as well as community trophic interactions. Within the framework of the BIOACID II project (Biological Impacts of Ocean ACIDification), the overarching goal of this thesis was to study the effects of ocean acidification on zooplankton, focusing on copepods and jellyfish. The main results are described in four chapters (CHAPTER I to IV), each of which corresponds to a manuscript. The first part of this thesis evaluated pCO2 effects on natural mesozooplankton communities from a boreal fjord (CHAPTER I) and the subtropical Northeast Atlantic (CHAPTER II). Large-scale pelagic mesocosm units (a Kiel Off-Shore Mesocosms for Future Ocean Simulations : KOSMOS) were artificially enriched in CO2 to simulate future ocean conditions. In both experiments, we detected species-specific sensitivities to ocean acidification in copepods, as well as positive pCO2 effect on total mesozooplankton abundances under high-CO2 bloom conditions, caused by a bottom-up effect. During the Gullmar Fjord KOSMOS2013 experiment (CHAPTER I) species-specific sensitivities to CO2 were detected in copepods, as well as in hydromedusae. However, these effects on single species were not translated into the structure or the diversity of the community, likely due to the overwhelmingly dominance of Pseudocalanus acuspes, which resulted to be more abundant under acidic conditions, especially the younger (copepodite) life stage. In the Gran Canaria KOSMOS2014 study (CHAPTER II) a significant effect of pCO2 on phytoplankton succession was detected, ultimately affecting the development of the plankton community only after a simulated bloom event. The zooplankton community responded to the phytoplankton bloom in all mesocosms, although the response was delayed under high pCO2 conditions. The most abundant mesozooplankters were calanoid copepods, which did not respond to CO2 treatments during the pre-bloom phase of the experiment. However calanoids were more abundant under elevated pCO2 conditions than in low- pCO2 levels in the post-bloom phase. Bottom-up effects of CO2-driven increases in phyto- and microzooplankton standing stocks would explain the increase in copepod abundance during both experiments. These results suggest that, under realistic end-of-century scenarios, the above-mentioned ocean acidification effects detected on copepods could potentially affect biomass transfer to higher trophic levels. As in community experiments it is not possible to separate out the pCO2 direct and indirect effects, mesocosms studies were combined with laboratory experiments in the second part of this thesis work. The aim was to evaluate direct and indirect effects of global change conditions on the two main groups of interest for this thesis: copepods and jellyfish. Apart from direct acidification effects, the increasing carbon availability in the marine environment will likely change primary production and the quality of phytoplankton as food for higher trophic levels, showing higher C:nutrient ratios as CO2 availability increases. Hence, a change in biochemical composition when culturing algae (Rhodomonas salina) in elevated pCO2 levels caused a change in food quality, affecting zooplankton by decreased growth and development. Indirect negative pCO2 effects were observed on the dinoflagellate Oxyrrhis marina and nauplii and copepodite stages of the copepod Acartia tonsa. Direct pH effects on these consumers seem to be of lesser importance than the indirect effects caused by a CO2-associated decrease in algal quality when having only a food source (CHAPTER III), unlike the positive CO2-effect observed in copepods when feeding on natural plankton communities. Direct pH effects on zooplankton, however, must be placed in a global change context, considering that ocean acidification in future oceans will not act alone but in combination with other climate factors such as warming and deoxygenation. The direct effects of these three stressors in conjunction were thus studied on 1-day-old ephyrae of the moon jellyfish (Aurelia aurita) from a North Sea subpopulation off Helgoland Island (Germany). The results obtained during this experiment point that end-of-century pCO2 scenarios will not affect these ephyrae in a substantial way. However, A. aurita may not be robust to larger changes in ocean pH, warming and deoxygenation, especially if simultaneous increases in atmospheric pCO2 levels and seawater temperature occur (CHAPTER IV). A. aurita is an ecologically and economically relevant species due to its interactions with commercially important fish species, hence the tolerance or resilience of this jellyfish to climate change might be detrimental for future fisheries

Slippery brazillian trade union moviment and impact in the working class: the case of pro- fessional secretaries and executive secretaries

Anais das IV Jornadas Internacionais de Problemas Latino-Americanos: Lutas, Experiências e Debates na América Latina - ISBN 978-950-793-223-6 - Orgs. Paulo Renato da Silva ; Mario Ayala ; Fabricio Pereira da Silva ; Fernando José MartinsO Movimento Sindical brasileiro, desde o final do século XX, vive uma crise de identi- dade, ocasionada pela queda do socialismo real e, sobretudo, pelas transformações advindas do novo sistema de produção. Assim, este trabalho se propõe a identificar como se deu o enfraqueci- mento das lutas de classe, ao longo dos anos, bem como a pulverização do sindicato, apontando as repercussões desta fragmentação para o proletariado. Toma-se por base os trabalhadores Secretá- rios e Secretários Executivos, analisados a partir do principal veículo de comunicação da categori- a: a Revista Excelência. A fundamentação teórica se dá por meio de autores como Marx e Engels, Antunes, Mészáros, dentre outros. Os resultados apontam para uma substancial perda de consciên- cia de classe por parte destes profissionais, demandando do Movimento Sindical contemporâneo a renovação de suas estratégias e a retomada histórica de suas lutas, para além do imediatismo.PPG – IELA – UNIL

Can DFT Calculations Provide Useful Information for SERS Applications?

: Density functional theory (DFT) calculations allow us to reproduce the SERS (surface-enhanced Raman scattering) spectra of molecules adsorbed on nanostructured metal surfaces and extract the most information this spectroscopy is potentially able to provide. The latter point mainly concerns the anchoring mechanism and the bond strength between molecule and metal as well as the structural and electronic modifications of the adsorbed molecule. These findings are of fundamental importance for the application of this spectroscopic technique. This review presents and discusses some SERS-DFT studies carried out in Italy as a collaboration between the universities of Modena and Reggio-Emilia and of Florence, giving an overview of the information that we can extract with a combination of experimental SERS spectra and DFT modeling. In addition, a selection of the most recent studies and advancements on the DFT approach to SERS spectroscopy is reported with commentary

DFT and TD-DFT Study of the Chemical Effect in the SERS Spectra of Piperidine Adsorbed on Silver Colloidal Nanoparticles

The surface-enhanced Raman scattering (SERS) spectra of piperidine adsorbed on silver/chloride colloids were studied by a combined density functional theory (DFT)/time dependent DFT (TD-DFT) approach. The mechanism of chemical enhancement on the Raman signals is due to at least two contributions: the first comes from the changes in the molecular force constants and the dynamic polarizabilities of the normal modes, when the molecule is chemisorbed. DFT calculations satisfactorily reproduce the SERS spectra of piperidine adsorbed on silver, showing that the species formed on the silver particle is a complex formed by a deprotonated piperidine linked to a silver cation. A second contribution to the SERS chemical enhancement is due to a resonance Raman effect occurring when the wavelength of the Raman excitation falls within the electronic excitation band of the molecule/metal complex. Actually, the SERS spectra of piperidine show a significant dependence on the wavelength of the laser excitation, with a marked enhancement in the green-light region. TD-DFT calculations on the most-probable complex explain this behavior, because a strong excitation band of the complex is calculated in the green spectral region. This pinpoints that a resonance between the exciting radiation and the absorption band of this complex is responsible for this enhancement effect

Intervenções urbanas em espaços de desvalia. Transformar para valorizar.

The worldwide transformations that took place in the 20th century redefined the cities fate in this new century. The consolidation of urbanization, the technological revolution that fostered globalization, the economic restructuration and informalization, modified space and time concepts, bringing populations closer together and provoking political transformations. They made contemporaries cities protagonists of world events and as a consequence of such processes, worthlessness spaces appeared and cities all over the world started to bet on the strategy of acting in this problematic areas through initiatives aimed at promoting intentional transformations to obtain a multidimensional valorization urban, financial, environmental, cultural and social. In short, such urban initiatives intend to make cities more competitive, sustainable, creative, productive and fair. Also in Brazil, countless worthless spaces appeared in waterfronts, central areas, and deactivated industrial/urbanized areas, as well as in sub-used or misused areas lacking infrastructure and public services where it is imperative and urgent to perform urban initiatives. This research proposes as a thesis that urban initiatives, when carried out based on an adequate politicalinstitutional model, transform and give value to worthless spaces in their multiple dimensions, offering better quality of life to their residents and helping to fulfill the social role of the city. We intend to prove this thesis through the analysis of national and international cases and by introducing thoughts, critique and guidelines as a contribution to the improvement of the urban initiatives implementation processes, in particular to those regarding worthless areas of Brazilian citiesCoordenação de Aperfeiçoamento de Pessoal de Nível SuperiorAs transformações mundiais ocorridas no século XX redefiniram os rumos da cidade neste novo século. A consolidação da urbanização, a revolução tecnológica que impulsionou a globalização, a reestruturação econômica e a informacionalização modificaram conceitos de tempo e espaço, aproximando os povos, e provocaram transformações políticas enfim, tornaram as cidades contemporâneas protagonistas dos acontecimentos mundiais. Em consequência desses processos, também surgiram espaços de desvalia, e no mundo inteiro as cidades começaram a apostar na estratégia de intervir nessas áreas-problema através de intervenções destinadas a promover transformações intencionais para obter valorização multidimensional urbanística, econômica, ambiental, cultural e social. Em síntese, tais intervenções urbanas visam a tornar a cidade contemporânea competitiva, sustentável, criativa, produtiva e justa. Também no Brasil, nos maiores centros urbanos surgiram inúmeros espaços de desvalia em frentes hídricas, em zonas centrais, em áreas industriais/urbanizadas desativadas e em áreas subutilizadas ou de uso indevido, carentes de infraestrutura e de serviços públicos, onde é imprescindível e urgente a realização de intervenção urbana. Esta pesquisa propõe como tese que as intervenções urbanas, quando implantadas a partir de um modelo político-institucional adequado, transformam e valorizam os espaços de desvalia em suas múltiplas dimensões, proporcionando melhor qualidade de vida aos residentes, buscando dar cumprimento à função social da cidade. Pretende-se ver esta tese comprovada na análise de casos internacionais e nacionais ao apresentar reflexões críticas e diretrizes como contribuição para a melhoria dos processos de implementação das intervenções urbanas, especialmente nos espaços de desvalia das cidades brasileira

Assessment of the basis set effect on the structural and electronic properties of organic-protected gold nanoclusters

We have investigated the structural and optical properties of five monolayer-protected gold nanoclusters with a combination of exchange–correlation functionals, namely B-PBE for the geometry relaxation and CAM-B3LYP for the time-dependent calculations. We have tested the accuracy of five different basis sets in reproducing the experimental structures of these nanoclusters, and we have found that even a rather small basis set (single zeta) can outperform a significantly larger one (double zeta) if some selected atoms are treated with polarization functions. Namely, the sulfur and phosphorous atoms of the capping thiols and phosphines usually are hypervalent when bonded to the gold inner core; therefore, polarization functions allow them significantly more structural flexibility. With the two best performing basis sets, we carried out optical calculations and found that the resulting UV–Vis profiles are largely similar, in particular the energy and orbital contributions of the optical gaps are very close. The results support the use of the small basis set proposed here to investigate larger nanoclusters with general hybrid and range-corrected hybrid functionals

Schistosoma-associated chronic septicemic salmonellosis : evolution of knowledge and immunopathogenic mechanisms

A salmonelose septicêmica prolongada é uma entidade clinicamente individualizada caracterizada por febre prolongada com hepatoesplenomegalia que ocorre em indivíduos esquistossomóticos coinfectados com salmonelas. Os mecanismos imunopatogênicos são vários e dependem das peculiaridades das interações entre as salmonelas e várias espécies do gênero Schistosoma. As modificações ocasionadas no sistema imunitário pela infecção parasitária são responsáveis pela evolução do quadro da doença. Nesta revisão, analisamos a evolução do conhecimento sobre a entidade e discutimos os possíveis mecanismos imunofisiopatogênicos que concorrem para seu desenvolvimento. _______________________________________________________________________________ ABSTRACTChronic septicemic salmonellosis is an individualized clinical entity characterized by prolonged fever with enlargement of the liver and spleen that occurs in Schistosoma-infected individuals who are coinfected with Salmonella. Several immunopathogenic mechanisms are involved, and they depend on the peculiarities of the interactions between Salmonella and various species of the genus Schistosoma. The modifications to the immune system that are caused by parasite infection are responsible for the evolution of the disease. In this review, we analyze the evolution of the knowledge on this entity and discuss the possible immuno-physiopathogenic mechanisms that contribute towards its development

Las redes de la supervivencia oncológica: con la vida de nuevo

Este trabalho tem origem na tese de doutorado que objetivou compreender a experiência da radioterapia oncológica para os pacientes sob referencial teórico-metodológico da antropologia interpretativa e do método etnográfico. Os informantes foram 10 pacientes de ambos os sexos, na faixa etária de 34 a 80 anos. Os dados foram coletados de março a agosto de 2007 por entrevistas semiestruturadas e observações participantes. Pela análise interpretativa proposta por Hammersley e Atkinson, construímos os núcleos de significados - Alterações na vida do sobrevivente ao câncer e à radioterapia e O sobrevivente controlando a sua vida e tecendo as teias do futuro. Entendemos que a enfermagem ultrapassa a dimensão biológica do cuidar quando compreende as teias tecidas pelos sobreviventes oncológicos para o ajuste à nova vida, pois eles percebem os limites existenciais, incorporam a doença e o tratamento, inserindo-os num processo liminar que persiste para o resto da vida.This study originates from a doctoral dissertation that aimed to better understand patients' oncological radiotherapy experience, given the theoretical and methodological reference of interpretative anthropology and the ethnographic method. The informants were 10 patients of both sexes, aged 34 to 80. The data was collected from March to August of 2007 through semi-structured interviews and participant observations. Through the interpretative analysis proposed by Hammersley and Atkinson, we constructed the clusters of meanings - Life alterations for the cancer and radiation survivor, and The survivor controlling their lives and weaving webs of the future. We understand nursing to go beyond the biological dimension of care when it includes the webs woven by cancer survivors to adjust to a new life, as they realize their existential limits, incorporate the disease and treatment, and insert them in a preliminary process which persists for the rest of their lives.Este trabajo proviene de la tesis que objetivó comprender la experiencia de radioterapia para pacientes con cáncer, a partir del referencial teórico y metodológico de la antropología interpretativa y del método etnográfico. Los informantes fueron 10 pacientes de ambos sexos, entre 34 a 80 años. Los datos fueron recolectados de marzo a agosto de 2007, por entrevistas semiestructuradas y observaciones participantes. A través del análisis interpretativo propuesto por Hammersley y Atkinson, construimos los siguientes grupos de significados - Cambios en la vida del sobreviviente del cáncer y la radiación, y, El sobreviviente controlando su vida y tejiendo las redes del futuro. Creemos que la enfermería ultrapasa la dimensión biológica de la atención cuando incluye las redes tejidas por los sobrevivientes de cáncer para adaptarse a la nueva vida, porque ellos perciben los límites existenciales, la incorporación de la enfermedad y el tratamiento, colocándolos en un proceso limítrofe, persistente para el resto de la vida

Reduction of the transverse effective charge of optical phonons in ZnO under pressure

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Appl. Phys. Lett. 96, 231906 (2010) and may be found at https://doi.org/10.1063/1.3447798."From Raman scattering on a-plane wurtzite ZnO crystals we obtained a decreasing splitting between longitudinal and transversal optical phonons with A1 and E1 symmetry as a function of hydrostatic pressure up to 5.5 GPa. Consequently, the transverse effective charge (e∗T) exhibits a strong reduction with increasing pressure, yielding 2.17–14.6×10−3 P/GPa and 2.04–13.7×10−3 P/GPa (in units of the elementary charge) for the A1 and E1 phonons, respectively. We find a clear systematic in the linear pressure coefficient of e∗T with bond polarity for the series of wide-band gap semiconductors SiC, AlN, GaN, and ZnO.DFG, 43659573, SFB 787: Halbleiter - Nanophotonik: Materialien, Modelle, Bauelement