Bioturbation experiments in the Venice Lagoon

Short experiments (14–21 days) were carried out during autumn 1998 and spring 1999 at one selected site of the Venice Lagoon to measure bioturbation activities and mixing rates, as well as to obtain quantitative information on benthos functionality. Fluorescent sediment particles (luminophores, 63–350 μm) were introduced as pulse inputs at the sediment surface. The concentration–depth profiles of the tracer were simulated with a new advection– diffusion–non local model applied under non-steady state conditions. This allowed the quantification of the mixing parameters associated with different mechanisms: biodiffusion (Db), bioadvection (W) and non-local mixing (Ke,z1, z2). A parameter RS (removed sediment) was also calculated to account for the flux of sediment due to nonlocal transport. Results show that bioturbation was dominated by biodiffusion in autumn and by bioadvection in spring. Mean mixing parameters Db, W, and RS changed from 3.09 to 0.87 cm2 y−1, from 0.93 to 15.50 y−1 and from 5.85 to 7.79 g cm−2 y−1, respectively

Crystal-chemistry of sulfates from apuan alps (Tuscany, Italy). i. Crystal structure and hydrogen bond system of melanterite, Fe(H2O)6(SO4)·H2O

Melanterite, ideally Fe(H2O)6SO4·H2O, from the pyrite+iron oxide ore deposit of Fornovolasco (Apuan Alps, Tuscany, Italy) has been fully characterized through electron microprobe analysis, micro-Raman spectroscopy, and X-ray diffraction. Melanterite occurs as cm-sized greenish fibrous efflorescences on pyrite or rare pseudo-octahedral colorless crystals, up to 5 mm in size. Electron microprobe analysis (in wt% - average of ten spot analyses normalized to 100 wt% without H2O) gave: SO3 52.98, FeO 45.53, MgO 1.49, sum 100.00. Assuming the occurrence of 7 H2O groups per formula unit, the chemical formula can be written as (Fe0.95Mg0.06)Σ1.01(SO4)·7H2O. The Raman spectrum of melanterite is characterized by bending and stretching modes of (SO4) and H2O groups. Melanterite crystallizes in the space group P21/c, with unit-cell parameters a=14.0751(8), b=6.5014(4), c=11.0426(6) Å, β=105.632(3)°, V=973.11(10) Å3, Z=4. The crystal structure of melanterite refined to R1 = 0.024 on the basis of 3457 unique reflections with Fo>4σ(Fo) and 179 refined parameters. It can be described as formed by undulating layers showing the alternation, along a, of SO4 groups and Fe-centered octahedra coordinated by H2O groups. The occurrence of a complex hydrogen bond system plays a fundamental role in the crystal structure of melanterite

Crystal-chemistry of sulfates from the Apuan Alps, Tuscany, Italy. VIII. New data on khademite, Al(SO4)F(H2O)5

AbstractKhademite, ideally Al(SO4)F(H2O)5, from the Monte Arsiccio mine, Apuan Alps, Tuscany, Italy, has been characterised through quantitative electron microprobe analysis, micro-Raman spectroscopy and single-crystal X-ray diffraction. Khademite occurs as colourless to whitish tabular crystals, up to 5 mm. Electron microprobe analysis (in wt.%, average of 20 spot analyses) gave: SO3 35.43, Al2O3 21.27, F 6.92, H2Ocalc 39.73, sum 103.35, –O = F 2.92, total 100.43. On the basis of 10 anions per formula unit, assuming the occurrence of 5 H2O groups and 1 (F+OH) atom per formula unit, its chemical formula can be written as Al0.96S1.02O4[F0.84(OH)0.16]Σ1.00⋅5H2O. The Raman spectrum of khademite is characterised by the occurrence of vibrational modes of SO4 groups and by broad and strong bands due to the O–H stretching modes. Khademite is orthorhombic, space group Pcab, with unit-cell parameters a = 11.1713(2), b = 13.0432(3), c = 10.8815(2) Å, V = 1585.54(5) Å3 and Z = 8. The crystal structure refinement converged to R1 = 0.0293 on the basis of 2359 unique reflections with Fo > 4σ(Fo) and 152 refined parameters. The crystal structure of khademite is characterised by the alternation, along b, of two distinct kinds of {010} layers, one formed by [001] rows of isolated Al-centred octahedra, connected to each other through H bonds, and the other showing isolated SO4 groups. Along b, oxygen atoms belonging to SO4 groups act as acceptor of H bonds from H2O groups coordinating Al atoms. The new data improved the description of the H bonds in khademite and led us to discuss about the possible existence of its (OH)-analogue, rostite. In addition, Raman spectroscopic data were collected on the same crystal used for the crystal-chemical characterisation, allowing a comparison with previous results

Secondary Sulfates from the Monte Arsiccio Mine (Apuan Alps, Tuscany, Italy): Trace-Element Budget and Role in the Formation of Acid Mine Drainage

A suite of sulfate minerals from the Monte Arsiccio mine (Apuan Alps, Northern Tuscany, Italy), previously identified by using both X-ray diffraction and micro-Raman spectroscopy, was studied through inductively coupled plasma mass spectrometry (ICP-MS), in order to determine their trace-element content. Several elements (Tl, Rb, As, Sb, Co, Ni, Cu, Zn, and Cr) were found above the detection limits. Among them, some are important from an environmental perspective and may reach relatively high concentrations (e.g., Tl = 1370–2988 μg/g; As = 505–1680 μg/g). Thus, these sulfates may act as transient sinks for some of these potentially toxic elements, as well as for sulfate ions and acidity. Indeed, dissolution experiments revealed the ability of these secondary minerals to produce a significant pH decrease of the solutions, as well as the release of Fe, Al, and K as major ions. This work discusses the relation between the budget of trace elements and the crystal chemistry of sulfate minerals and provides new insights about the environmental role played by the sulfate dissolution in controlling the quality of water in acid mine drainage systems

A simplified constitutive model for a SEBS gel muscle simulant - Development and experimental validation for finite elements simulations of handgun and rifle ballistic impacts

An original simplified constitutive model is proposed to simulate the effects of ballistic impacts on blocks of synthetic muscle simulant based on mineral oil and styrene ethylene-butylene styrene polymers (SEBS) as a convenient substitute for Fackler ballistic gelatin. The model is based on a quasi-static elastic-plastic model associated with hydrodynamic properties regulated by a polynomial equation of state. The paper illustrates the development and experimental validation of the model to simulate 9x21mm FMJ round-nose, 7.62x39 mm FMJ, and 5.56x45 mm NATO bullets penetrating 145x145x400 mm gel blocks. All material parameters are provided to be implemented in built-in LS-Dyna keywords. The validation confirms the effectiveness of the model and suggests possible further developments. The work also confirms the tested synthetic gel as a valid and convenient substitute for Fackler 10% ballistic gelatin at 4 °C

Diseño del trazado de una nueva línea ferroviaria entre Gandia y Denia

[ES] En este trabajo fin de Grado se realizara la definición del diseño geométrico de un tramo de ferrocarril entre dos poblaciones costeras como son Gandia (Valencia) y Denia (Alicante). Esta línea existió y fue cerrada hace más de 40 años. En este trabajo se pretende realizar un estudio experimental para recuperar esa línea de comunicación ferroviaria con un nuevo y moderno trazado. Para ello, y tras obtener la cartografía digital de la zona, se definirá mediante el programa informático ISTRAM ISPOL un nuevo diseño de planta y rasante para ver la viabilidad de este tramo con la normativa ferroviaria actual[EN] In this final project, definition of the geometric design of a section of railway between two coastal towns (Gandia and Denia) will be carried out. This line existed and was closed more than 40 years ago. In this work we intend to carry out an experimental study to recover that line of railway communication with a new and modern layout. For this, and after obtaining the digital cartography of the area, a new plant design will be defined through the ISTRAM ISPOL software to see the viability of this section with the current railway normativeGaray Sánchez, CM. (2019). Diseño del trazado de una nueva línea ferroviaria entre Gandia y Denia. http://hdl.handle.net/10251/127018TFG

Alternating flow filtration as an alternative to internal spin filter based perfusion process: Impact on productivity and product quality

The application of an alternating flow filtration (ATF) system adapted to a stirred tank bioreactor as an alternative to internal spin filter was studied using CHO cells producing a fusion protein. As expected, it was possible to reach higher cell densities (maximum 50 x 106 vs 20 x 106 cells/ml) and achieve longer runs with the ATF device (50 days vs 30 days), since it is known that this cell retention device is less affected by fouling. Even tough specific cell yield was similar for both systems; volumetric production of the reactor using the ATF was almost 70% higher than the production achieved using the internal spin filter due to higher cell density and a two fold increase in the perfusion rate. Taking into consideration that it was observed certain degree of retention of the product at the end of the run we assume that this difference in the volumetric production could be even higher working with a bigger pore size or changing the hollow fiber cartridge around day 35. The later can also have a positive impact on the length of the process increasing the average daily production and overall yield. Cell specific perfusion rate was optimized for both the internal spin filter and ATF. A lower rate was achieved for the ATF, resulting in a harvest with a higher product concentration, which supposes a benefit for downstream processing. Several quality attributes were studied, including misfolded, clipped forms and product glycosylation profile. Differences between both systems were detected only for glycosylation profile, resulting in a decrease of fucosylated glycoforms. These results constitute valuable data for the optimization of recombinant protein production in perfusion processes since a two fold increase in the chronological productivity of a production facility could be easily achieved as long as downstream scale up is possible

Criterios para resolver casos de operaciones no reconocidas efectuadas mediante el uso de tarjetas de crédito o débito

El presente trabajo se enfoca en analizar determinados pronunciamientos por parte de la Sala de Protección al Consumidor del Instituto Nacional de Defensa de la Competencia y de la Protección de la Propiedad Intelectual (INDECOPI) en materia de operaciones no reconocidas efectuadas mediante la utilización de tarjetas de crédito o débito. En ese sentido, tiene como objetivo analizar qué criterios deben ser considerados por las entidades financieras -al implementar sus sistemas de monitoreo- y por la autoridad resolutiva de INDECOPI al ordenar la devolución del monto por operaciones no reconocidas realizadas con tarjeta de crédito o débito. Se partirá por exponer los criterios que han sido utilizados por los órganos resolutivos de INDECOPI al ordenar la devolución del monto por operaciones no reconocidas realizadas con tarjeta de crédito o débito. Así, se encontrará que existe una sostenida discrepancia de criterios por parte del voto mayoritario y el voto en discordia en las resoluciones emitidas relativas a este tipo de operaciones. En segundo lugar, se describirá el sentido de la perspectiva constitucional del derecho de protección al consumidor financiero del cual se tendrá que una tutela efectiva de protección al consumidor financiero implica tomar en consideración la vulnerabilidad de determinados usuarios. Finalmente, en base a lo analizado en los dos capítulos precedentes, se planteará a algunas propuestas normativas las cuales apuntan a mejorar el tratamiento actual de las operaciones no reconocidas realizadas con tarjetas de crédito o débitoTrabajo académic