Preclinical evaluation of the immunogenicity of C-type HIV-1-based DNA and NYVAC vaccines in the Balb/C mouse model.

As part of a European initiative (EuroVacc), we report the design, construction, and immunogenicity of two HIV-1 vaccine candidates based on a clade C virus strain (CN54) representing the current major epidemic in Asia and parts of Africa. Open reading frames encoding an artificial 160-kDa GagPolNef (GPN) polyprotein and the external glycoprotein gp120 were fully RNA and codon optimized. A DNA vaccine (DNA-GPN and DNA-gp120, referred to as DNA-C), and a replication-deficient vaccinia virus encoding both reading frames (NYVAC-C), were assessed regarding immunogenicity in Balb/C mice. The intramuscular administration of both plasmid DNA constructs, followed by two booster DNA immunizations, induced substantial T-cell responses against both antigens as well as Env-specific antibodies. Whereas low doses of NYVAC-C failed to induce specific CTL or antibodies, high doses generated cellular as well as humoral immune responses, but these did not reach the levels seen following DNA vaccination. The most potent immune responses were detectable using prime:boost protocols, regardless of whether DNA-C or NYVAC-C was used as the priming or boosting agent. These preclinical findings revealed the immunogenic response triggered by DNA-C and its enhancement by combining it with NYVAC-C, thus complementing the macaque preclinical and human phase I clinical studies of EuroVacc.

Geotecnologias aplicadas à avaliação de parâmetros biofísicos do Pantanal

O objetivo deste trabalho foi avaliar parâmetros biofísicos de superfície do Bioma Pantanal com a aplicação de geotecnologias. Foram utilizados o algoritmo Sebal ("surface energy balance algorithm for land"), imagens do sensor Modis ("moderate‑resolution imaging spectroradiometer") e o mapa de classes de uso e cobertura da terra. Os resultados obtidos para NDVI, temperatura da superfície, albedo, fluxo de calor sensível diário, saldo de radiação diário e evapotranspiração real diária foram consistentes com dados de literatura para os diferentes usos e cobertura da terra, e corroboram a eficiência da capacidade analítica e sinóptica das estimativas do Sebal. Tais resultados mostram o potencial de geotecnologias na implementação de modelos ou algoritmos voltados para a compreensão da dinâmica de processos biofísicos de interação solo‑planta‑atmosfera do Pantanal.

Obstrução do horizonte calculada a partir de modelo digital de elevação

O objetivo deste trabalho foi avaliar a exatidão do cálculo da obstrução do horizonte, a partir de um modelo digital de elevação (MDE), em diferentes situações topográficas. O material utilizado incluiu um MDE disponível para a região da Serra Gaúcha, RS, receptores GPS, câmera digital, lente grande‑angular e os programas Idrisi, Arcview/ArcGIS e Solar Analyst. Foram adquiridas fotografias hemisféricas, e coletadas as coordenadas de 16 locais na área de estudo. As coordenadas e o MDE foram utilizados para calcular a obstrução do horizonte com uso do algoritmo Solar Analyst. Foram comparadas a fração aberta do céu calculada e a obtida pelas fotografias hemisféricas. O coeficiente de determinação foi de 0,8428, tendo-se observado superestimativa média de 5,53% da fração aberta do céu. Os erros são atribuídos principalmente à obstrução pela vegetação, que não pode ser identificada pelo MDE. A obstrução do horizonte, causada pelo relevo na Serra Gaúcha, pode ser calculada satisfatoriamente pelo Solar Analyst, a partir de um MDE interpolado de cartas topográficas na escala 1:50.000.

The three main stumbling blocks for anticancer T cells.

Memory and effector T cells have the potential to counteract cancer progression, but often fail to control the disease, essentially because of three main stumbling blocks. First, clonal deletion leads to relatively low numbers or low-to-intermediate T cell receptor (TCR) affinity of self/tumor-specific T cells. Second, the poor innate immune stimulation by solid tumors is responsible for inefficient priming and boosting. Third, T cells are suppressed in the tumor microenvironment by inhibitory signals from other immune cells, stroma and tumor cells, which induces T cell exhaustion, as demonstrated in metastases of melanoma patients. State-of-the-art adoptive cell transfer and active immunotherapy can partially overcome the three stumbling blocks. The reversibility of T cell exhaustion and novel molecular insights provide the basis for further improvements of clinical immunotherapy.

Efficient self-synchronised blind audio watermarking system based on time domain and FFT amplitude modification

Many audio watermarking schemes divide the audio signal into several blocks such that part of the watermark is embedded into each of them. One of the key issues in these block-oriented watermarking schemes is to preserve the synchronisation, i.e. to recover the exact position of each block in the mark recovery process. In this paper, a novel time domain synchronisation technique is presented together with a new blind watermarking scheme which works in the Discrete Fourier Transform (DFT or FFT) domain. The combined scheme provides excellent imperceptibility results whilst achieving robustness against typical attacks. Furthermore, the execution of the scheme is fast enough to be used in real-time applications. The excellent transparency of the embedding algorithm makes it particularly useful for professional applications, such as the embedding of monitoring information in broadcast signals. The scheme is also compared with some recent results of the literature.

Algoritmos genéticos para la anonimización de grafos

Peer-reviewed

Aproximación al reajuste automático de centroides mediante la heurística de Lloyd para resolver el problema de las K-Medias

Peer-reviewed

A robust audio watermarking scheme based on MPEG 1 Layer 3 Compression

This paper describes an audio watermarking scheme based on lossy compression. The main idea is taken from an image watermarking approach where the JPEG compression algorithm is used to determine where and how the mark should be placed. Similarly, in the audio scheme suggested in this paper, an MPEG 1 Layer 3 algorithm is chosen for compression to determine the position of the mark bits and, thus, the psychoacoustic masking of the MPEG 1 Layer 3compression is implicitly used. This methodology provides with a high robustness degree against compression attacks. The suggested scheme is also shown to succeed against most of the StirMark benchmark attacks for audio.

VoIP: Making Secure Calls and Maintaining High Call Quality

Modern multimedia communication tools must have high security, high availability and high quality of service (QoS). Any security implementation will directly impact on QoS. This paper will investigate how end-to-end security impacts on QoS in Voice over Internet Protocol (VoIP). The QoS is measured in terms of lost packet ratio, latency and jitter using different encryption algorithms, no security and just the use of IP firewalls in Local and Wide Area Networks (LAN and WAN). The results of laboratory tests indicate that the impact on the overall performance of VoIP depends upon the bandwidth availability and encryption algorithm used. The implementation of any encryption algorithm in low bandwidth environments degrades the voice quality due to increased loss packets and packet latency, but as bandwidth increases encrypted VoIP calls provided better service compared to an unsecured environment.

On an IDS Model for Mobile Ad Hoc Networks

Manet security has a lot of open issues. Due to its character-istics, this kind of network needs preventive and corrective protection. Inthis paper, we focus on corrective protection proposing an anomaly IDSmodel for Manet. The design and development of the IDS are consideredin our 3 main stages: normal behavior construction, anomaly detectionand model update. A parametrical mixture model is used for behav-ior modeling from reference data. The associated Bayesian classi¯cationleads to the detection algorithm. MIB variables are used to provide IDSneeded information. Experiments of DoS and scanner attacks validatingthe model are presented as well.

Genetic algorithm for sequencing in midex model non-permutation flowshops using constrained buffers

Este trabajo presenta un Algoritmo Genético (GA) del problema de secuenciar unidades en una línea de producción. Se tiene en cuenta la posibilidad de cambiar la secuencia de piezas mediante estaciones con acceso a un almacén intermedio o centralizado. El acceso al almacén además está restringido, debido al tamaño de las piezas.AbstractThis paper presents a Genetic Algorithm (GA) for the problem of sequencing in a mixed model non-permutation flowshop. Resequencingis permitted where stations have access to intermittent or centralized resequencing buffers. The access to a buffer is restricted by the number of available buffer places and the physical size of the products.

Imputação múltipla livre de distribuição em tabelas incompletas de dupla entrada

O objetivo deste trabalho foi propor um novo algoritmo de imputação múltipla livre de distribuição, por meio de modificações no método de imputação simples recentemente desenvolvido por Yan para contornar o problema de desbalanceamento de experimentos. O método utiliza a decomposição por valores singulares de uma matriz e foi testado por meio de simulações baseadas em duas matrizes de dados reais completos, provenientes de ensaios com eucalipto e cana-de-açúcar, com retiradas aleatórias de valores em diferentes percentagens. A qualidade das imputações foi avaliada por uma medida de acurácia geral que combina a variância entre imputações e o viés quadrático médio delas em relação aos valores retirados. A melhor alternativa para imputação múltipla é um modelo multiplicativo que inclui pesos próximos a 1 para os autovalores calculados com a decomposição. A metodologia proposta não depende de pressuposições distribucionais ou estruturais e não tem restrições quanto ao padrão ou ao mecanismo de ausência dos dados.

Suunnittelun tunnusluvut

Diplomityön tavoitteena oli kehittää Andritzin Kuitulinja-divisioonalle tunnuslukuja, työkaluja sekä menetelmiä projektin johdon jasuunnittelun eri osa-alueiden arviointiin, hinnoitteluun ja seurantaan Työn teoriaosuudessa käsiteltiin projektiliiketoimintaa, suunnitteluaja sen hankintaa, tunnuslukuja sekä mittaamista projektiympäristössä. Työn pääpaino oli kuitenkin empiriaosuudella, jossa aluksi tutustuttiin yksityiskohtaisesti työssä tutkittaviin osa-alueisiin. Tiedonkeruuvaiheessa kerättiin suuri määrätunnuslukujen laskemiseksi tarvittavaa tietoa toteutetuista tai vielä hieman keskeneräisistä projekteista. Työn kirjallinen osuus ja kerätty numeerinen tieto yhdistettiin tunnuslukujen analysointivaiheessa, jossa tutkittiin eri tunnuslukujen soveltuvuutta mittaamiseen. Tunnusluvut soveltuivat hyvin joidenkin osa-alueiden kuten prosessi- ja putkistosuunnittelun mittaamiseen. Joidenkin osa-alueiden, kuten rakennussuunnittelun mittaaminen tunnuslukujen avulla oli vaikeampaa tunnuslukujen suuresta hajonnasta johtuen. Eri osa-alueille saatiin kuitenkin määritettyä parhaat tunnusluvut, projektien luokitteluperusteet ja standardiarvot. Työn lopputuloksina saatiin päätavoitteena ollut tunnuslukumittaristo sekä mittaamisen yhtenäistämiseksi luotu tiedonkeruulomake. Mittaamisen tehostamiseksi ja kehittämiseksi tehtiin useita jatkotutkimus- ja kehitysehdotuksia. Lisäksi työssä esitettiin uusi menetelmä projektinohjauksen ja resurssisuunnittelun tueksi.

Viranomaisvaatimusten mukaisten putkistojen hankinta, asennus ja korjaus

Tämän työn tarkoituksena oli kirjallisuustutkimuksen ja aikaisemmin valmistuneiden putkitöiden avulla määritellä ohjeistus viranomaisvaatimusten mukaisten putkistojen valmistamista varten. Tarkasteluesimerkkeinä oli kolme erilaista putkityötä. Näiden seikkojen kautta vahvistui käsitys ohjeistuksen tarpeellisuudesta, mikä oli jo työn tavoitteissa yhtenä päämääränä. Aluksi selvitetään lainsäädäntöä ja sitä, mitä laki vaati putkistoilta. Seuraavaksi tarkastellaan standardeja valmistuksen näkökannalta ja siitä seurauksena syntyi valmistusohje. Sen jälkeen käsitellään putkistoista tehtyjä dokumentaatioita, joita oli jo valmistettu lainsäädännön vaihtumisen jälkeen. Kokoamalla em. tutkimukset on saatu aikaiseksi ohjeistus, jota seuraamallavalmistaja voi valmistaa putkiston, joka täyttää lain ja asetuksen vaatimuksen.Tässä työssä ei tarkasteltu tuotannon tehostamista asennusolosuhteissa eikä laatutavoitteita. Tuloksena syntyi ohjeistus, joka huomioi erilaiset lait ja asetukset, kun kyseessä on putkistojen hankinta, asennus tai korjaus putkistoissa, joita viranomaismääräykset ja asetukset valvovat. Putkistojen asennuksen ja tuotannon tehostaminen sekä automatisoinnin tai mekanisoinnin käyttö hitsauksessa ja hitsauksen laadun varmistus voivat olla tämän diplomityön jälkeisiä tutkimusaiheita.

Genome-wide prediction of matrix attachment regions that increase gene expression in mammalian cells.

Gene transfer in eukaryotic cells and organisms suffers from epigenetic effects that result in low or unstable transgene expression and high clonal variability. Use of epigenetic regulators such as matrix attachment regions (MARs) is a promising approach to alleviate such unwanted effects. Dissection of a known MAR allowed the identification of sequence motifs that mediate elevated transgene expression. Bioinformatics analysis implied that these motifs adopt a curved DNA structure that positions nucleosomes and binds specific transcription factors. From these observations, we computed putative MARs from the human genome. Cloning of several predicted MARs indicated that they are much more potent than the previously known element, boosting the expression of recombinant proteins from cultured cells as well as mediating high and sustained expression in mice. Thus we computationally identified potent epigenetic regulators, opening new strategies toward high and stable transgene expression for research, therapeutic production or gene-based therapies.