Video Watermarking Based on Interactive Detection of Feature Regions

International audienceVideo watermarking is very important in many areas of activity and especially in multimedia applications. Therefore, security of video stream has recently become a major concern and has attracted more and more attention in both the research and industrial domains. In this perspective, several video watermarking approaches are proposed but, based on our knowledge, there is no method which verified the compromise between invisibility and robustness against all usual attacks. In our previous work, we proposed a new video watermarking approach based on feature region generated from mosaic frame and multi-frequential embedding. This approach allowed obtaining a good invisibility and robustness against the maximum of usual attacks. In our future work, we propose to optimize the choice of the region of interest by using crowdsourcing technique. This last one is an emerging field of knowledge management that involves analyzing the behavior of users when the

Candidalysin crucially contributes to Nlrp3 inflammasome activation by Candida albicans hyphae

Candida albicans is an opportunistic fungal pathogen that can cause life-threatening infections, particularly in immunocompromised patients. C. albicans induced activation of the Nlrp3 inflammasome, leading to secretion of bioactive interleukin 1β (IL-1β) is a crucial myeloid cell immune response needed for antifungal host defense. Being a pleiomorphic fungus, C. albicans can provoke Nlrp3 inflammasome responses only upon morphological transformation to its hyphal appearance. However, the specific hyphal factors that enable C. albicans to activate the Nlrp3 inflammasome in primary macrophages remain to be revealed. Here, we identify candidalysin, a peptide derived from the hypha-specific ECE1 gene, as a fungal trigger for Nlrp3 inflammasome-mediated maturation and secretion of IL-1β from primary macrophages. Direct peptide administration experiments showed that candidalysin was sufficient for inducing secretion of mature IL-1β from macrophages in an Nlrp3 inflammasome-dependent manner. Conversely, infection experiments using candidalysin-deficient C. albicans showed that candidalysin crucially contributed to the capacity of this fungus to induce maturation and secretion of IL-1β from primary macrophages. These complementary observations identify the expression of candidalysin as one of the molecular mechanisms by which hyphal transformation equips C. albicans with its proinflammatory capacity to elicit the release of bioactive IL-1β from macrophages.IMPORTANCE Candidiasis is a potentially lethal condition that is caused by systemic dissemination of Candida albicans, a common fungal commensal residing mostly on mucosal surfaces. The transition of C. albicans from an innocuous commensal to an opportunistic pathogen goes hand in hand with its morphological transformation from a fungus to a hyphal appearance. On the one hand, the latter manifestation enables C. albicans to penetrate tissues, while on the other hand, the expression of many hypha-specific genes also endows it with the capacity to trigger particular cytokine responses. The Nlrp3 inflammasome is a crucial component of the innate immune system that provokes release of the IL-1β cytokine from myeloid cells upon encountering C. albicans hyphae. Our study reveals the peptide candidalysin as one of the hypha-derived drivers of Nlrp3 inflammasome responses in primary macrophages and, thus, contributes to better understanding the fungal mechanisms that determine the pathogenicity of C. albicans

Susceptibility of Candida glabrata biofilms to echinocandins: alterations in the matrix composition

Candidiases are the most recurrent fungal infections, especially among immunosuppressed patients. Although Candida albicans is still the most widespread isolated species, non-Candida albicans Candida species have been increasing. The goal of this work was to determine the susceptibility of C. glabrata biofilms to echinocandins and to evaluate their effect on the biofilm matrix composition, comparing the results with other Candida species. Drug susceptibilities were assessed through the determination of minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC) and minimum biofilm eradication concentration (MBEC) of caspofungin (Csf) and micafugin (Mcf). The -1,3 glucans content of the matrices was assessed after contact with the drugs. The data suggest that, generally, after contact with echinocandins, the concentration of -1,3 glucans increased. These adjustments in the matrix composition of C. glabrata biofilms and the chemical differences between Csf and Mcf, seem responsible and may determine the effectivity of the drug responses.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 [POCI-01–0145-FEDER-006684] and BioTecNorte operation [NORTE-01–0145-FEDER-000004] funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte, Célia F. Rodrigues’ [SFRH/BD/93078/2013] PhD grant and M. Elisa Rodrigues [SFRH/BPD/95401/2013] post-doctoral grant.info:eu-repo/semantics/publishedVersio

Adhesion of Candida albicans and Candida dubliniensis to acrylic and hydroxyapatite

The aim of this work was to compare the ability of strains of Candida albicans and Candida dubliniensis to adhere to acrylic and hydroxyapatite (HAP). In order to interpret the adhesion results, the surface properties of cells and materials were determined. Surface tension components (polar and apolar) and hydrophobicity were calculated through contact angle measurement and the elemental composition was determined by X-ray photoelectron spectroscopy (XPS). The results showed no significant differences in the number of adhered cells of both species to acrylic and hydroxyapatite. This was corroborated by the similarities in their surface properties and elemental composition. For both species, the adhesion to acrylic increased in the presence of artificial saliva due to the increase in the electron-donor capacity of this material. In the absence of artificial saliva, the number of adhered cells to HAP was greater than to acrylic, on account of the higher number of electron-donor groups of HAP. Hydrophobicity played a minor role in the adhesion process of both candidal species. Conversely, Lewis acid–base interactions seamed to govern this phenomenon.Fundação para a Ciência e a Tecnologia (FCT) - BD3195/2000, Programa Operacional “Ciência, Tecnologia, Inovação” (POCTI) POCTI/BIO/42638/2001

Effect of farnesol on structure and composition of staphylococcus epidermidis biofilm matrix

Staphylococcus epidermidis is the most frequent cause of nosocomial sepsis and catheter-related infections in which biofilm formation is considered to be one of the main virulence mechanisms. Moreover, their increased resistance to conventional antibiotic therapy enhances the need to develop new therapeutical agents. Farnesol, a natural sesquiterpenoid present in many essential oils, has been described as impairing bacterial growth. The aim of this study was to evaluate the effect of farnesol on the structure and composition of biofilm matrix of S. epidermidis. Biofilms formed in the presence of farnesol (300 μM) contained less biomass, and displayed notable changes in the composition of the biofilm matrix. Changes in the spacial structure were also verified by confocal scanning laser microscopy (CSLM). The results obtained by the quantification of extracellular polymers and by wheat germ agglutinin (WGA) fluorescent detection of glycoproteins containing β(1→4)-N-acetyl-d-glucosamine support the hypothesis that farnesol causes disruption of the cytoplasmic membrane and consequently release of cellular content.Fernanda Gomes and Pilar Teixeira fully acknowledge the financial support of Fundacao para a Ciencia e Tecnologia (FCT) through the grants SFRH/BD/32126/2006 and SFRH/BPD/26803/2006, respectively

Conflicts in Energy Transitions : Eine Reflexion über das online-Seminar für Master-studierende vom SoSe 2020

Das Seminar „Conflicts in Energy Transitions“, welches im Sommersemester 2020 von Prof. Dr. Michael Böcher und Dr. Ulrike Zeigermann angeboten wurde, stellte sich - in digitaler Form - den aktuellen Diskussionen über erneuerbare Energien, deren Konfliktpotenzialen und Zukunftsausblicken. Das Seminar wurde in drei Themenabschnitte unterteilt, um Struktur in die Komplexität des Themenfeldes zu bringen, sowie das asynchrone Lernen zu fördern. Diese Themenfelder werden im Folgenden vorgestellt und diskutiert, inwiefern dieser Aufbau den Studierenden das selbstverantwortliche Bearbeiten der Module, welche alle vier Wochen in synchroner - und aufgrund der Covid-19-Pandemie in digitaler Form - besprochen wurden, ermöglichte

PENGARUH NET PROFIT MARGIN (NPM), RETURN ON ASSET (ROA), RETURN ON EQUITY (ROE), DEBT TO EQUITY RATIO (DER), PRICE TO BOOK VALUE (PBV) DAN PRICE EARNING RATIO (PER) TERHADAP HARGA SAHAM SYARIAH PERUSAHAAN YANG TERDAFTAR DI JAKARTA ISLAMIC INDEX (JII) PERIODE 2016 – 2018

ABSTRAK PENGARUH NET PROFIT MARGIN (NPM), RETURN ON ASSET (ROA), RETURN ON EQUITY (ROE), DEBT TO EQUITY RATIO (DER), PRICE TO BOOK VALUE (PBV) DAN PRICE EARNING RATIO (PER) TERHADAP HARGA SAHAM SYARIAH PERUSAHAAN YANG TERDAFTAR DI JAKARTA ISLAMIC INDEX (JII) PERIODE 2016 – 2018 OLEH: Gandhi Jabra Adista Pesatnya perkembangan pasar modal kini menarik perhatian masyarakat dan pemilik modal untuk berinvestasi di pasar modal. Selama tahun 2016-2018, harga rata-rata harga saham perusahaan yang terdaftar di Jakarta Islamic Index mengalami kondisi yang berfluktuasi. Rasio keuangan yang diduga mempengaruhi naik turunnya harga saham adalah NPM, ROA, ROE, DER, PBV dan PER. Penelitian ini bertujuan untuk mengetahui pengaruh Net Profit Margin (NPM), Return On Asset (ROA), Return On Equity (ROE), Debt to Equity Ratio (DER), Price to Book Value (PBV) dan Price Earning Ratio (PER) terhadap harga saham syariah perusahaan yang terdaftar di Jakarta Islamic Index tahun 2016-2018 baik secara parsial maupun secara simultan. Metode penelitian yang digunakan dalam penelitian ini adalah metode penelitian kuantitatif sedangkan jenis data yang digunakan adalah data sekunder. Populasi dalam penelitian ini berjumlah sebanyak 30 perusahaan, sedangkan sampel sebanyak 9 perusahaan, dengan periode data dari tahun 2016-2018. Pengambilan sampel menggunakan metode purposive sampling. Analisis data yang digunakan dalam penelitian ini menggunkan metode regresi linear berganda dengan bantuan program Eviews 10 for windows. Hasil penelitian menyimpulkan bahwa secara parsial variabel Net Profit Margin (NPM) (X1), Return On Asset (ROA) (X2), Price to Book Value (PBV) (X5) dan Earning Ratio (PER) (X6) berpengaruh signifikan terhadap harga saham syariah pada perusahaan yang terdaftar di Jakarta Islamic Index tahun 2016-2018 sedangkan variabel Return On Equity (ROE) (X3), Debt to Equity Ratio (DER) (X4) tidak berpengaruh signifikan. Kemudian berdasarkan uji secara simultan menyimpulkan bahwa variable Net Profit Margin (NPM) (X1), Return On Asset (ROA) (X2), Return On Equity (ROE) (X3), Debt to Equity Ratio (DER) (X4), Price to Book Value (PBV) (X5) dan Price Earning Ratio (PER) (X6) secara simultan berpengaruh signifikan terhadap harga saham syariah pada perusahaan yang terdaftar di Jakarta Islamic Index tahun 2016-2018. Kata Kunci: Net Profit Margin (NPM), Return On Asset (ROA), Return On Equity (ROE), Debt to Equity Ratio (DER), Price to Book Value (PBV), Price Earning Ratio (PER), Harga Saham Syaria

Effect of farnesol on planktonic and biofilm cells of Staphylococcus epidermidis

Staphylococcus epidermidis is now amongst the most important pathogenic agents responsible for bloodstream nosocomial infections and for biofilm formation on indwelling medical devices. Its increasing resistance to common antibiotics is a challenge for the development of new antimicrobial agents. Accordingly, the goal of this study was to evaluate the effect of farnesol, a natural sesquiterpenoid, on Staphylococcus epidermidis planktonic and biofilm cells. Farnesol displayed a significant inhibitory effect on planktonic cells. Small concentrations (100 μM) were sufficient to exhibit antibacterial effect on these cells. In biofilm cells the effect of farnesol was not so pronounced and it seems to be strongly dependent on the cells metabolic activity and amount of matrix. Interestingly, the effect of farnesol at 200 μM was similar to the effect of vancomycin at peak serum concentration either in planktonic or biofilm cells. Overall, the results indicate a potential antibacterial effect of farnesol against S. epidermidis, and therefore the possible action of this molecule on the prevention of S. epidermidis related infections.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/32126/2006, SFRH/BPD/26803/200

Spectroscopic Study of Ni(II)-4, 4’, 4’’, 4’ ’’ – Tetrasulfophthalocyanine In Aqueous Solution

It was determined spectrally that a monomer-dimer equilibrium exists in aqueous solutions of Ni-TSPC4- over a concentration range of 5 x 10-8 – 10-4 M. Equilibrium measurements were made under natural ionic strength conditions at 29°, 39° and 49°C. The values obtained for the equilibrium constants at 29°, 39° and 49°C were 2.4 x 108, 6.6 x 107 and 2.9 x 107 M-1, respectively. These results indicated that the equilibrium strongly favors dimer formation. This study also showed that nickel is second to copper in enhancing the dimerization of metallotetrasulfophthalocyanine complexes. However, metals in general inhibit dimer formation relative to the free ligand. The dimerization reaction of Ni-TSPC4- is exothermic with thermodynamic parameters of ΔG° = -11.6 kcal/mole, ΔH = -20.9 kcal/mole, and ΔS = -31 e.u. The dimerization process is thus favored from an energetic point of view despite the unfacorable entropy change. Spectral measurements made on Ni-TSPC4- in aqueous pyridine solutions in the concentration range of .05 - 6.0% pyridine (by volume) indicated a dipyridinated dimer complex of Ni-TSPC4- was formed. Using a modified version of the Benesi-Hildebrand equation, the following equilibrium was proposed : D + 2Py = D(Py)2. The overall equilibrium constants for this system at 15°, 21°, 30° and 40°C were 1.7, 1.9, 2.8, 3.6 and 4.4 M-2, respectively. The equilibrium reaction is endothermic with thermodynamic parameters of: ΔG=6.2 kcal/mole, ΔH =6.9 kcal/mole, and ΔS=25 e.u. Thus, the equilibrium reaction was favored thermodynamically due to the favorable entropy change associated with the process. Ligand studies indicated that only pyridine and polupyridine ligands bind to Ni-TSPC4- and cause a spectral change. This study also showed that Ni-TSPC4- cannot be used as an oxygen carrier in biological systems