Thermal analysis, X-ray diffraction, spectroscopy studies and magnetic properties of the new compound Tl2HAsO4.Te(OH)6

The Tl2HAsO4.Te(OH)6 (TlAsTe) compound crystallizes in the triclinic system P1 with unit cell parameters: a= 7.100(10) Å, b= 7.281(13) Å, c= 8.383(11) Å, α= 76.91(1)°, β= 87.16(1)°, γ= 66.96(2)°, Z= 2 and V= 388.19(1) Å3. This new structure can be described as a lamellar one with the atomic arrangement being built by planes of Te(OH)6 octahedra alterning with planes of arsenate tetrahedra. Raman and infrared spectra recorded at room temperature confirm the presence of As  and Te  groups and characterize the hydrogen bonds present in the crystal lattice. Differential scanning calorimerty shows the presence of three-phase transitions at 396 K, 408 K and 430 K present in the title compound. Typical thermal analyses, such as differential thermal analysis and thermogravimetry show that the decomposition of this material starts at about T= 445 K. Magnetization curve of Tl2HAsO4·Te(OH)6 substance have revealed a diamagnetic response overall temperature range studied

Fermentación controlada de aceitunas verdes picholine marroquíes sometidas a choque térmico e inoculadas sin sal

The present work reports the controlled fermentation of heat-shocked, unsalted and inoculated green olives. The effects of heat-shock (60, 70 and 80 °C three times for 5 min), inoculation with the oleuropeinolytic strain of L. plantarum FSO175 (L.p-FSO175) and the addition of Cell-Free Supernatant of C. pelliculosa L18 (CFS of C.p-L18) on the fermentation process of unsalted green olives were examined. The results showed a drastic reduction in the initial indigenous Enterobacteria, and an improvement in the acidification of heat-shocked olives at 70 and 80 °C, when compared to 60 °C. The inoculation with L.p-FSO175 and addition of CFS of C.p-L18 enhanced the fermentation and preservation of unsalted green olives, indicated by a significant decrease in pH, increase in free acidity and total disappearance of Enterobacteria. The heat-shock treatment at high temperature (80 °C), inoculation with L.p-FSO175 and addition of CFS of C.p-L18 led to the best reduction in bitterness, and favorable color changes (L, a, and b) in fermented olives. This sequential method led to more appreciated sensory characteristics (mainly bitterness and color) of fermented olives, lower spoilage incidence in olives, and reduced fermentation time to 50 days, and therefore may be suitable to control the fermentation of unsalted green olives of the Moroccan picholine variety.El presente trabajo reporta la fermentación controlada de aceitunas verdes sometidas a choque térmico, sin salar e inoculadas. Se estudian los efectos del choque térmico (60 °C, 70 °C y 80 °C tres veces durante 5 min), la inoculación con cepa oleuropeinolítica de L. plantarum FSO175 (L.p-FSO175) y la adición de sobrenadante libre de células de C. pelliculosa L18 (CFS de C.p-L18), sobre el proceso de fermentación de aceitunas verdes sin salar. Los resultados mostraron la drástica reducción de las enterobacterias autóctonas iniciales, y la mejora de la acidificación de las aceitunas sometidas a choque térmico de 70 °C y 80 °C, en comparación con 60 °C. La inoculación con L.p-FSO175 y la adición de CFS de C.p-L18 mejoró la fermentación y conservación de las aceitunas verdes sin salar, indicada por una disminución significativa del pH, aumento de la acidez libre y desaparición total de enterobacterias. El choque térmico a alta temperatura (80 °C), la inoculación con L.p-FSO175 y la adición de CFS de C.p-L18 condujeron a una mejor reducción del amargor y cambios de color favorables (L, a y b) en aceitunas fermentadas. Este método secuencial, que permitió apreciar las características sensoriales (principalmente amargor y color) de las aceitunas fermentadas, y una menor incidencia de deterioro en las aceitunas, y redujo el tiempo de fermentación a 50 días, puede ser adecuado para controlar la fermentación de aceitunas verdes sin salar de Marruecos, variedad picholine

New Fisheries-related data from the Mediterranean Sea (April 2015)

In this second Collective Article with fisheries-related data from the Mediterranean Sea we present the evaluation of bony structures in aging of Barbus tauricus, otolith dimensions-body length relationships for two species (Trachinus draco and Synchiropus phaeton), information on the growth of juvenile Thunnus thynnus and of Ruvettus pretiosus, weight-length relationships for three species (Aulopus fiamentosus, Thunnus thynnus and Tylosurus acus imperialis) and data on feeding habits and reproduction of Aulopus fiamentosus

Quantitative localized proton-promoted dissolution kinetics of calcite using scanning electrochemical microscopy (SECM)

Scanning electrochemical microscopy (SECM) has been used to determine quantitatively the kinetics of proton-promoted dissolution of the calcite (101̅4) cleavage surface (from natural “Iceland Spar”) at the microscopic scale. By working under conditions where the probe size is much less than the characteristic dislocation spacing (as revealed from etching), it has been possible to measure kinetics mainly in regions of the surface which are free from dislocations, for the first time. To clearly reveal the locations of measurements, studies focused on cleaved “mirror” surfaces, where one of the two faces produced by cleavage was etched freely to reveal defects intersecting the surface, while the other (mirror) face was etched locally (and quantitatively) using SECM to generate high proton fluxes with a 25 μm diameter Pt disk ultramicroelectrode (UME) positioned at a defined (known) distance from a crystal surface. The etch pits formed at various etch times were measured using white light interferometry to ascertain pit dimensions. To determine quantitative dissolution kinetics, a moving boundary finite element model was formulated in which experimental time-dependent pit expansion data formed the input for simulations, from which solution and interfacial concentrations of key chemical species, and interfacial fluxes, could then be determined and visualized. This novel analysis allowed the rate constant for proton attack on calcite, and the order of the reaction with respect to the interfacial proton concentration, to be determined unambiguously. The process was found to be first order in terms of interfacial proton concentration with a rate constant k = 6.3 (± 1.3) × 10–4 m s–1. Significantly, this value is similar to previous macroscopic rate measurements of calcite dissolution which averaged over large areas and many dislocation sites, and where such sites provided a continuous source of steps for dissolution. Since the local measurements reported herein are mainly made in regions without dislocations, this study demonstrates that dislocations and steps that arise from such sites are not needed for fast proton-promoted calcite dissolution. Other sites, such as point defects, which are naturally abundant in calcite, are likely to be key reaction sites

Antimicrobial Activities of Bacteria Associated with the Brown Alga Padina pavonica

General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. Macroalgae belonging to the genus Padina are known to produce antibacterial compounds that may inhibit growth of human-and animal pathogens. Hitherto, it was unclear whether this antibacterial activity is produced by the macroalga itself or by secondary metabolite producing epiphytic bacteria. Here we report antibacterial activities of epiphytic bacteria isolated from Padina pavonica (Peacocks tail) located on northern coast of Tunisia. Eighteen isolates were obtained in pure culture and tested for antimicrobial activities. Based on the 16S rRNA gene sequences the isolates were closely related to Proteobacteria (12 isolates; 2 Alpha-and 10 Gammaproteobacteria), Firmicutes (4 isolates) and Actinobacteria (2 isolates). The antimicrobial activity was assessed as inhibition of growth of 12 species of pathogenic bacteria (Aeromonas salmonicida, A. hydrophila, Enterobacter xiangfangensis, Enterococcus faecium, Escherichia coli, Micrococcus sp., Salmonella typhimurium, Staphylococcus aureus, Streptococcus sp., Vibrio alginoliticus, V. proteolyticus, V. vulnificus) and one pathogenic yeast (Candida albicans). Among the Firmicutes, isolate P8, which is closely related to Bacillus pumilus, displayed the largest spectrum of growth inhibition of the pathogenic bacteria tested. The results emphasize the potential use of P. pavonica associated antagonistic bacteria as producers of novel antibacterial compounds

Whole genome sequencing,molecular typing and in vivovirulence of OXA-48-producingEscherichia coli isolates includingST131 H30-Rx, H22 and H41subclones

Carbapenem-resistant Enterobacteriaceae, including the increasingly reported OXA-48 Escherichia coli producers, are an emerging public health threat worldwide. Due to their alarming detection in our healthcare setting and their possible presence in the community, seven OXA-48-producing, extraintestinal pathogenic E. coli were analysed by whole genome sequencing as well as conventional tools, and tested for in vivo virulence. As a result, five E. coli OXA-48-producing subclones were detected (O25:H4-ST131/PST43-fimH30-virotype E; O25:H4-ST131/PST9-fimH22-virotype D5, O16:H5-ST131/ PST506-fimH41; O25:H5-ST83/PST207 and O9:H25-ST58/PST24). Four ST131 and one ST83 isolates satisfied the ExPEC status, and all except the O16:H5 ST131 isolate were UPEC. All isolates exhibited local inflammatory response with extensive subcutaneous necrosis but low lethality when tested in a mouse sepsis model. The blaOXA-48 gene was located in MOBP131/IncL plasmids (four isolates) or within the chromosome (three ST131 H30-Rx isolates), carried by Tn1999-like elements. All, except the ST83 isolate, were multidrug-resistant, with additional plasmids acting as vehicles for the spread of various resistance genes. This is the first study to analyse the whole genome sequences of blaOXA-48-positive ST131, ST58 and ST83 E. coli isolates in conjunction with experimental data, and to evaluate the in vivo virulence of blaOXA-48 isolates, which pose an important challenge to patient management

Antioxidant and cytotoxic activities of sulfated polysaccharides from five different edible seaweeds

In recent times, there has been a growing interest in the exploration of antioxidants and global trend toward the usage of seaweeds in the food industries. The low molecular weight up to 14 kDa sulfated polysaccharides of seaweeds (Portieria hornemannii, Spyridia hypnoides, Asparagopsis taxiformis, Centroceras clavulatum and Padina pavonica) were evaluated for in vitro antioxidant activities and cytotoxic assay using HeLa cell line and also characterized by FTIR. The high yield (7.74% alga dry wt.) of sulfated polysaccharide was observed in P. hornemannii followed by S. hypnoides (0.69%), C. clavulaum (0.55%) and A. taxiformis (0.17%). In the brown seaweed P. pavonica, the sulfated polysaccharide yield was 2.07%. High amount of sulfate was recorded in the polysaccharide of A. taxiformis followed by C. clavulaum, P. pavonica, S. hypnoides and P. hornemannii as indicative for bioactivity. The FTIR spectroscopic analysis supports the sulfated polysaccharides of S. hypnoides, C. clavulatum and A. taxiformis are similar to agar polymer whereas the spectral characteristics of P. hornemannii have similarities to carrageenan. The higher DPPH activity and reducing power were recorded in the polysaccharide of brown seaweed P. pavonica than the red seaweeds as follows: DPPH activities: S. hypnoides > A. taxiformis > C. clavulatum > P. hornimanii; Reducing power: A. taxiformis > P. hornimanii > S. hypnoides > C. clavulatum. The polysaccharide fractions contain up to 14 kDa from red seaweeds P. hornemannii and S. hypnoides followed by brown seaweed P. pavonica exhibit cytotoxic activity in HeLa cancer cell line (and are similar to structural properties of carrageenan extracted from P. hornemannii). The low molecular weight agar like polymer of S. hypnoides and alginate like brown seaweed P. pavonica showing better in vitro antioxidant activities that are capable of exhibiting cytotoxicity against HeLa cell line can be taken up further in-depth investigation for nutraceutical study.University of Algarve: DL 57/2016info:eu-repo/semantics/publishedVersio

Recherches sur l’anatomie et la biologie de

La morphologie et l’anatomie de Microcotyle salpae trouvé à Tunis chez Box salpa sont redécrites. La localisation de ces parasites sur les branchies est précisée. Les larves non ciliées ont été obtenues et on donne leur anatomie. L’influence de l’hôte sur les modalités de l’éclosion et de l’infestation est dégagée expérimentalement

n. g. n. sp. (Trematoda, Sanguinicolidae) parasite du système circulatoire de

Description d’un nouveau genre de Sanguinicolidae, Hyperandrotrema parasite d’un Cetorhinus maximus pêché sur les côtes tunisiennes. Ce nouveau genre, placé dans la sous-famille des Chimaerohemecinae, se caractérise par un œsophage court et de longs caecums digestifs en forme de « U » renversé. La diagnose de la sous-famille des Chimaerohemecinae est amendée

n. g.-n. sp.

Les auteurs décrivent Neonchocotyle pastinacae n. g. n. sp. parasite des arcs branchiaux de Dasyatis pastinaca (Linné, 1758) capturé dans le golfe de Tunis, ainsi que la larve non-nageante de cet animal