Hydrological and erosion response at micro-plot to -catchment scale following forest wildfire, north-central Portugal

Wildfires can have important impacts on hydrological and soil erosion processes, due to the destruction of vegetation cover and changes to soil properties. According to Shakesby and Doerr (2006), these wildfire effects are: i) much better known at small spatial scales (especially erosion plots) than at the scale of catchments; ii) much better studied with respect to overland flow and streamflow (and, then, especially peak discharges) than to soil erosion. Following up on a precursor project studying runoff generation and the associated soil losses from micro-plot to slope-scale in Portuguese eucalypt forests, the EROSFIRE-II project addresses the connectivity of these processes across hillslopes as well as within the channel network. This is done in the Colmeal study area in central Portugal, where the outlet of an entirely burnt catchment of roughly 10 ha was instrumented with a gauging station continuously recording water level and tubidity, and five slopes were each equipped with 4 runoff plots of < 0,5 m2 (“micro-plot”) and 4 slope-scale plots as well as 1 slope-scale sediment fence. Starting one month after the August 2008 wildfire, the plots were monitored at 1- to 2-weekly intervals, depending on the occurrence of rainfall. The gauging station became operational at the end of November 2008, since the in-situ construction of an H-flume required several weeks. A preliminary analysis of the data collected till the end of 2008, focusing on two slopes with contrasting slope lengths as well as the gauging station: revealed clear differences in runoff and erosion between: (i) the micro-plot and slope-scale plots on the same hillslope; (ii) the two slopes; (iii) an initial dry period and a subsequent much wetter period; (iv) the slopes and the catchment-scale, also depending on the sampling period. These results suggest that the different processes govern the hydrological and erosion response at different spatial scales as well as for different periods, with soil water repellency playing a role during the initial post-fire period. The current presentation will review these preliminary results based on the data collected during the first year after the wildfire

Estudio experimental del Sistema de Albañilería Integral en la construcción de viviendas sismorresistentes. Experimental study of the Integral Masonry System in the construction of earthquake resistant houses

This paper presents the application of the Integral Masonry System (IMS) to the construction of earthquake resistant houses and its experimental study. To verify the security of this new type of building in seismic areas of the third world two prototypes have been tested, one with adobe and the other with hollow brick. In both cases it’s a two-story 6x6x6 m3 house built to scale 1/2. The tests are carried out at the Laboratory of Antiseismic Structures of the Department of Engineering, Pontifical Catholic University of Peru in Lima, in collaboration with the UPM (Technical University of Madrid). This article shows the design process of the prototypes to test, including the sizing of the reinforcements, the characteristics of the tests and the results obtained. These results show that the IMS with adobe or brick remains stable with no significant cracks faced with a severe earthquake, with an estimated acceleration of 1.8 g. Este artículo presenta una aplicación del Sistema de Albañilería Integral (SAI) a la construcción de viviendas sismorresistentes y su estudio experimental. Para verificar su seguridad para su construcción en zonas sísmicas del tercer mundo se han ensayado dos prototipos, uno con adobe, y otro con ladrillo hueco. Se trata de una vivienda de 6x6x6 m3 y dos plantas que se construyen a escala 1/2. Los ensayos se realizaron en el Laboratorio de Estructuras Antisísmicas del Departamento de Ingeniería de la Pontificia Católica Universidad del Perú (PUCP) de Lima en colaboración con la UPM (Universidad Politécnica de Madrid). Este artículo muestra el proceso de diseño de los prototipos a ensayar, incluido el dimensionado de los refuerzos, las características de los ensayos y los resultados obtenidos. Estos resultados muestran que el SAI con adobe o ladrillo permanece estable sin grietas significativas ante un sismo severo, con una aceleración estimada de 1,8 g

Mineralization of layer-by-layer ultrathin films containing microfluidic-produced hydroxyapatite nanorods

We describe the assembly of layer-by-layer (LbL) ultrathin films containing bioactive hydroxyapatite (HAp) rod-shaped nanoparticles with mineralizing capacity. Monodisperse 96 nm long and 9 nm wide HAp nanorods with a surface charge of â 14 mV were produced with a microfluidic system. The negatively charged HAp nanorods were assembled with the polycation poly-L-lysine (PLL) in LbL fashion. The successful deposition of alternating layers was confirmed by quartz-crystal microbalance with dissipation monitoring. The Voigt-based viscoelastic model demonstrated steady film growth where three PLL/HAp bilayers reached a thickness of 70 nm. The bioactivity of [PLL/HAp]3 was evaluated in vitro by following the formation of a mineralized hydroxyapatite layer in simulated body fluid (SBF). X-ray diffraction, energy-dispersive X-ray spectroscopy and scanning electron microscopy (SEM) demonstrated formation of a crystalline hydroxyapatite layer and complete surface coverage within 7 days. SaOs-2 osteoblasts-like cells attached to the mineralized surfaces and developed longer filopodia extensions when compared to non-mineralized samples. Our results showed that [PLL/HAp]3 films are feasible osteoconductive coatings applicable to orthopedic implants and fixation devices.The authors acknowledge Fundación Ramón Areces, Xunta de Galicia (ED431B 2017/21, ED41E2018/08), Programa Iacobus, financial support from “Fundação para a Ciência e Tecnologia” (grant CEECIND/02842/2017 to R. R. C. and project Norte-01-0145-FEDER-022190) and the EC H2020 programme through the projects ELASTISLET (NMP-2014-646075

A novel hanging spherical drop system for the generation of cellular spheroids and high throughput combinatorial drug screening

We propose a novel hanging spherical drop system for anchoring arrays of droplets of cell suspension based on the use of biomimetic superhydrophobic flat substrates, with controlled positional adhesion and minimum contact with a solid substrate. By facing down the platform, it was possible to generate independent spheroid bodies in a high throughput manner, in order to mimic in vivo tumour models on the lab-on-chip scale. To validate this system for drug screening purposes, the toxicity of the anti-cancer drug doxorubicin in cell spheroids was tested and compared to cells in 2D culture. The advantages presented by this platform, such as feasibility of the system and the ability to control the size uniformity of the spheroid, emphasize its potential to be used as a new low cost toolbox for high-throughput drug screening and in cell or tissue engineering.The authors thank the precious help of Alessandra Zonari and Rui Domingues for capturing the confocal images. The authors acknowledge the financial support from the FCT-Fundacao para a Ciencia e para a Tecnologia through the Ph.D. grants with the references SFRH/BD/73119/2010, SFRH/BD/69529/2010 and SFRH/BD/71396/2010. We acknowledge the financial support of FEDER through the program Operacional Factores de Competitividade - COMPETE and from FCT - the Fundacao para a Ciencia e a Tecnologia under the project PTDC/CTM-BIO/1814/2012. We also thank the support by the European Research Council grant agreement ERC-2012-ADG 20120216-321266 for the project ComplexiTE

Development of a cryogenic APPLE CPMUE15 at BESSY II

Building on the innovative design of the In Vacuum APPLE IVUE32, a design for a 15mm period cryogenic elliptical undulator CPMUE15 is proposed. The undulator is to be developed under the ATHENA collaboration. Initially designed to provide a radiator for the SINBAD facility at DESY, a comparison is made for a design to provide an Afterburner device for FLASH

Quinazoline-Based Antivirulence Compounds Selectively Target Salmonella PhoP/PhoQ Signal Transduction System

The rapid emergence of multidrug resistance among bacterial pathogens has become a significant challenge to human health in our century. Therefore, development of next-generation antibacterial compounds is an urgent need. Two-component signal transduction systems (TCS) are stimulus-response coupling devices that allow bacteria to sense and elaborate adaptive responses to changing environmental conditions, including the challenges that pathogenic bacteria face inside the host. The differential presence of TCS, present in bacteria but absent in the animal kingdom, makes them attractive targets in the search for new antibacterial compounds. In Salmonella enterica, the PhoP/PhoQ two-component system controls the expression of crucial phenotypes that define the ability of the pathogen to establish infection in the host. We now report the screening of 686 compounds from a GlaxoSmithKline published kinase inhibitor set in a high-throughput whole-cell assay that targets Salmonella enterica serovar Typhimurium PhoP/PhoQ. We identified a series of quinazoline compounds that showed selective and potent downregulation of PhoP/PhoQ-activated genes and define structural attributes required for their efficacy. We demonstrate that their bioactivity is due to repression of the PhoQ sensor autokinase activity mediated by interaction with its catalytic domain, acting as competitive inhibitors of ATP binding. While noncytotoxic, the hit molecules exhibit antivirulence effect by blockage of S. Typhimurium intramacrophage replication. Together, these features make these quinazoline compounds stand out as exciting leads to develop a therapeutic intervention to fight salmonellosis.Fil: Carabajal, María Ayelén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Asquith, Christopher R. M.. University of North Carolina; Estados UnidosFil: Laitinen, Tuomo. University of North Carolina; Estados UnidosFil: Tizzard, Graham J.. University of North Carolina; Estados UnidosFil: Yim, Lucía. Universidad de la República; UruguayFil: Rial, Analía. Universidad de la República; UruguayFil: Chabalgoity, José A.. Universidad de la República; UruguayFil: Zuercher, William J.. University of North Carolina; Estados UnidosFil: Garcia Vescovi, Eleonora. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentin

The Joint Action of Sesquiterpene Lactones from Leaves as an Explanation for the Activity of Cynara cardunculus

The work described herein is a continuation of a previous study centered on the bioprospect of cardoon (Cynara cardunculus) leaf extracts through the isolation of secondary metabolites with phytotoxic activity. Chromatographic fractionations of the ethyl acetate extract and spectroscopic analysis showed that the majority of the components were sesquiterpene lactones. Of these compounds, aguerin B, grosheimin, and cynaropicrin were very active on etiolated wheat coleoptile, standard target species, and weed growth. The joint action of binary mixtures of these three active sesquiterpene lactones and one nonactive compound (11,13-dihydroxy-8-desoxygrosheimin) was studied. The activities of fixed-ratio mixtures were assessed on wheat coleoptile. The results can be interpreted with respect to a reference model by considering dose−response analyses and isobolograms with linear regression analyses. A total of 17 binary mixtures at different levels of inhibition (ED25, ED50, and ED75) were studied, and predominantly they responded additively (25). Deviations from additivity included seven synergistic responses and two antagonistic responses. The joint action of major sesquiterpene lactones isolated from C. cardunculus can explain the activities observed in extracts and fractions. The results reported here reiterate the utility of the wheat coleoptile bioassay as a quick tool to detect potential synergistic effects in binary mixtures

UC Updatable Databases and Applications

We define an ideal functionality \Functionality_{\UD} and a construction \mathrm{\Pi_{\UD}} for an updatable database (\UD). \UD is a two-party protocol between an updater and a reader. The updater sets the database and updates it at any time throughout the protocol execution. The reader computes zero-knowledge (ZK) proofs of knowledge of database entries. These proofs prove that a value is stored at a certain position in the database, without revealing the position or the value. (Non-)updatable databases are implicitly used as building block in priced oblivious transfer, privacy-preserving billing and other privacy-preserving protocols. Typically, in those protocols the updater signs each database entry, and the reader proves knowledge of a signature on a database entry. Updating the database requires a revocation mechanism to revoke signatures on outdated database entries. Our construction \mathrm{\Pi_{\UD}} uses a non-hiding vector commitment (NHVC) scheme. The updater maps the database to a vector and commits to the database. This commitment can be updated efficiently at any time without needing a revocation mechanism. ZK proofs for reading a database entry have communication and amortized computation cost independent of the database size. Therefore, \mathrm{\Pi_{\UD}} is suitable for large databases. We implement \mathrm{\Pi_{\UD}} and our timings show that it is practical. In existing privacy-preserving protocols, a ZK proof of a database entry is intertwined with other tasks, e.g., proving further statements about the value read from the database or the position where it is stored. \Functionality_{\UD} allows us to improve modularity in protocol design by separating those tasks. We show how to use \Functionality_{\UD} as building block of a hybrid protocol along with other functionalities

Unprecedented tuning of the in-plane easy axis in (100) magnetite films grown by IR-PLD

Conference paper presented at the IEEE International Magnetics Conference, held in Beijing (China) on May 11-15th, 2015.Magnetite (Fe3O4) is attracting much interest in the last years due to its robust ferrimagnetism down to nanometer thickness, good electrical conductivity and presumed half-metal character. In particular, Fe3O4 films are studied as ideal cases for the design of improved bulk magnets [1] and have been tentatively used in spin-valves and spin-LEDs. Fe3O4 presents a low-temperature metal-insulator transition, the Verwey transition (TV) which has also been proposed for spintronic applications. An open question is to what extent the preparation of Fe3O4 films can affect their detailed magnetic properties, such as the magnetic anisotropy axis. This information is required to efficiently apply Fe3O4 in technological multiphase magnets and spintronic applications [1]. Most of studies dealing with bulk and Fe3O4 thin film systems show room temperature (RT) in-plane magnetic easy axis. By contrast, we show in this work the preparation of pure stoichiometric Fe3O4 thin films with RT easy axes along the in-plane directions [2], i.e. rotated by 45º respect to previous studies. Fe3O4 films have been grown by ablation from a sintered hematite target using a nanosecond infrared (IR) laser at 1064 nm and a substrate temperature of 750 K [3]. Single crystal substrates of SrTiO3, MgAl2O4 and MgO have been used. The films were characterized using XRD, AFM, Raman and Mössbauer spectroscopies, vectorial magneto-optical Kerr effect microscopy (v-MOKE) and SQUID magnetometry. All films consisted of stoichiometric Fe3O4 and presented a Verwey transition at TV=115-118 K. RT in-plane hysteresis loops were measured by vectorial-MOKE as a function of the direction of the applied magnetic field in the 0º-360º range with an angular step of 5º. For all epitaxial films under study, the highest coercivity and remanence are found at 0º, 90º, 180º and 270º (i.e. directions), thus orthogonal to each other, while the lowest coercivity values are found between them [Figures 1(a) and 1(b), respectively]. This results in a well-defined four-fold symmetry indicative of biaxial magnetic anisotropy [2]. In order to verify this result, ferromagnetic resonance (FMR) experiments have been carried out at 9.4 GHz frequency. The angular dependence of the in-plane resonance field at RT for the Fe3O4 layers proves that the easy axes are indeed the in-plane directions (Fig. 2). Furthermore, spin-polarized low-energy electron microscopy (SPLEEM) has allowed imaging the individual magnetic domains at the surface of the films [2]. The magnetic domains present magnetization vectors along the in-plane ¿100¿ directions, while the domain walls are aligned with the in-plane ¿110¿ directions. The most probable cause for the observed magnetization easy-axis direction is the orientation of the anti-phase domain boundaries (APBs). It is known that depending on the orientation of the APBs, they can couple both ferromagnetically or antiferromagnetically the magnetite grains that lie across the boundary. We thus propose that the particular distribution and orientation of APBs that our growth conditions promote are responsible for the observed easy-axis directions of our films. Consequently, all angular studies here shown in addition to SPLEEM experiments demonstrate easy-axis orientation along in-plane directions, i.e., differing from that of bulk magnetite or films prepared by other techniques, and thus demonstrating the possibility of tuning the easy axis orientation in Fe3O4 films

A Novel Approach to Resonant Absorption of the Fast MHD Eigenmodes of a Coronal Arcade

The arched eld lines forming coronal arcades are often observed to undulate as magne- tohydrodynamic (MHD) waves propagate both across and along the magnetic eld. These waves are most likely a combination of resonantly coupled fast magnetoacoustic waves and Alfv\' en waves. The coupling results in resonant absorption of the fast waves, converting fast wave energy into Alfv\' en waves. The fast eigenmodes of the arcade have proven difficult to compute or derive analytically, largely because of the mathematical complexity that the coupling introduces. When a traditional spectral decomposition is employed, the discrete spectrum associated with the fast eigenmodes is often subsumed into the continuous Alfv \'en spectrum. Thus fast eigenmodes, become collective modes or quasi-modes. Here we present a spectral decomposition that treats the eigenmodes as having real frequencies but complex wavenumbers. Using this procedure we derive dispersion relations, spatial damping rates, and eigenfunctions for the resonant, fast eigenmodes of the arcade. We demonstrate that resonant absorption introduces a fast mode that would not exist otherwise. This new mode is heavily damped by resonant absorption, only travelling a few wavelengths before losing most of its energy