Comparison of experimental and numerical sloshing loads in partially filled tanks

Sloshing phenomenon consists in the movement of liquids inside partially filled tanks, whichgenerates dynamic loads on the tank structure. Resulting impact pressures are of great importance in assessingstructural strength, and their correct evaluation still represents a challenge for the designer due to the highnonlinearities involved, with complex free surface deformations, violent impact phenomena and influence of airtrapping. In the present paper a set of two-dimensional cases for which experimental results are available areconsidered to assess merits and shortcomings of different numerical methods for sloshing evaluation, namely twocommercial RANS solvers (FLOW-3D and LS-DYNA), and two own developed methods (Smoothed ParticleHydrodynamics and RANS). Impact pressures at different critical locations and global moment induced by watermotion for a partially filled tank with rectangular section having a rolling motion have been evaluated and resultsare compared with experiments

Hydrogen induced optically-active defects in silicon photonic nanocavities

This work was supported by Era-NET NanoSci LECSIN project coordinated by F. Priolo, by the Italian Ministry of University and Research, FIRB contract No. RBAP06L4S5 and by the EPSRC UKSp project. Partial financial support by the Norwegian Research Council is also acknowledged.We demonstrate intense room temperature photoluminescence (PL) from optically active hydrogen- related defects incorporated into crystalline silicon. Hydrogen was incorporated into the device layer of a silicon on insulator (SOI) wafer by two methods: hydrogen plasma treatment and ion implantation. The room temperature PL spectra show two broad PL bands centered at 1300 and 1500 nm wavelengths: the first one relates to implanted defects while the other band mainly relates to the plasma treatment. Structural characterization reveals the presence of nanometric platelets and bubbles and we attribute different features of the emission spectrum to the presence of these different kind of defects. The emission is further enhanced by introducing defects into photonic crystal (PhC) nanocavities. Transmission electron microscopy analyses revealed that the isotropicity of plasma treatment causes the formation of a higher defects density around the whole cavity compared to the ion implantation technique, while ion implantation creates a lower density of defects embedded in the Si layer, resulting in a higher PL enhancement. These results further increase the understanding of the nature of optically active hydrogen defects and their relation with the observed photoluminescence, which will ultimately lead to the development of intense and tunable crystalline silicon light sources at room temperature.Publisher PDFPeer reviewe

Nanoscale magnetic field mapping with a single spin scanning probe magnetometer

We demonstrate quantitative magnetic field mapping with nanoscale resolution, by applying a lock-in technique on the electron spin resonance frequency of a single nitrogen-vacancy defect placed at the apex of an atomic force microscope tip. In addition, we report an all-optical magnetic imaging technique which is sensitive to large off-axis magnetic fields, thus extending the operation range of diamond-based magnetometry. Both techniques are illustrated by using a magnetic hard disk as a test sample. Owing to the non-perturbing and quantitative nature of the magnetic probe, this work should open up numerous perspectives in nanomagnetism and spintronics

Boschi vetusti e riserve forestali nel Veneto: patrimoni di biodiversita\u300

Vengono sintetizzate le criticita\u300 emergenti legate alle dinamiche di cambiamento della biodiversita\u300 nelle foreste del Veneto anche esaminando i dati delle politiche forestali degli ultimi decenni e delle trasformazioni di boschi e foreste di montagna, collina e pianura conseguenti all\u2019abbandono colturale e ad iniziative locali di contrasto alle alterazioni del paesaggio forestale, di miglioramento ambientale ed estetico e di difesa della biodiversita\u300 forestale e naturalistica dei territori del Veneto. Seppur in un confronto europeo l'Italia e\u300 forse uno degli stati piu\u300 virtuosi nella gestione del patrimonio boschivo, sia in termini di risparmio di biomassa (35% di prelievo sull'incremento contro la media europea di oltre 60%) che per modalita\u300 di prelievo (e\u300 uno dei pochi stati dove il taglio a raso e\u300 vietato e, a differenza di molti paesi europei, non ammette l'imboschimento con specie esotiche), in questo approfondimento vengono esaminati gli scenari possibili di riferimento per una programmazione piu\u300 mirata, incisiva ed innovativa delle politiche di tutela della biodiversita\u300 forestale del Veneto, guardando ad alcune esperienze europee volte alla tutela e valorizzazione dei boschi antichi o vetusti. Boschi e foreste si stanno espandendo nel Veneto anche in pianura: ma questo trend e\u300 frutto dell\u2019abbandono colturale e/o conseguenza di una programmazione territoriale adeguata? Si propongono linee guida per iniziative locali di contrasto alla banalizzazione estetica ed ambientale del paesaggio e per contro di miglioramento della difesa della biodiversita\u300 forestale e naturalistica dei territori del Veneto partendo dalla tutela del patrimonio genetico dei \u201cboschi vetusti\u201d

Assessing the genetic diversity of rice originating from Bangladesh, Assam and West Bengal

Acknowledgements This work was funded by BBSRC research project BB/J00336/1. FS and a part of the proportion of the cost of the Illumina genotyping was funded by a Beachell-Borlag International Fellowship. The authors would like to acknowledge the help of Dr MK Sarmah in collecting seed samples of the landraces and improved cultivars from Assam used in this study and Dr. Ma. Elizabeth B. Naredo and Ms. Sheila Mae Q. Mercado for handling of IRGC accessions and preparation of DNAs for genotyping. All rice seeds used here were obtained with MTA agreements and seed and dry leaves imported into the UK under import licence IMP⁄SOIL⁄18⁄2009 issued by Science and Advice for Scottish Agriculture.Peer reviewedPublisher PD

Mutant huntingtin enhances activation of dendritic Kv4 K+ channels in striatal spiny projection neurons

Huntington\u27s disease (HD) is initially characterized by an inability to suppress unwanted movements, a deficit attributable to impaired synaptic activation of striatal indirect pathway spiny projection neurons (iSPNs). To better understand the mechanisms underlying this deficit, striatal neurons in ex vivo brain slices from mouse genetic models of HD were studied using electrophysiological, optical and biochemical approaches. Distal dendrites of iSPNs from symptomatic HD mice were hypoexcitable, a change that was attributable to increased association of dendritic Kv4 potassium channels with auxiliary KChIP subunits. This association was negatively modulated by TrkB receptor signaling. Dendritic excitability of HD iSPNs was rescued by knocking-down expression of Kv4 channels, by disrupting KChIP binding, by restoring TrkB receptor signaling or by lowering mutant-Htt (mHtt) levels with a zinc finger protein. Collectively, these studies demonstrate that mHtt induces reversible alterations in the dendritic excitability of iSPNs that could contribute to the motor symptoms of HD

Initial stages of oxidation at noble metal surfaces: The cases of Ag and Cu

The initial stages of oxide nucleation and surface oxide formation are hot topics at the moment due to the possible application of these materials in many fields of science and technology. The understanding of the parameters controlling these processes is therefore pivotal not only for the fundamental knowledge of the physical phenomenon but also for enabling the growth of better quality oxide phases, with a higher degree of order and/or a lower density of contaminants. Here I will summarize the main results obtained by a collaboration between experimental groups in Genova and Osaka and between the experimentalists in Genova and theoretical groups in Trieste and Ljubljana, on the initial oxidation of the noble metals Ag and Cu. I will show that the local morphology of surface defects and/or the dosing conditions are essential elements to determine the nature of the oxide form which starts to nucleate upon exposure to O2. On stepped Ag we find that, under vacuum conditions, the stoichiometry of the initial oxide nuclei is tuned by the atomic geometry at the low coordination site, while on Cu(410) the oxidation efficiency comes out to be highly enhanced both by the presence of steps and by exposure to hyperthermal oxygen. The relative amount of cuprous and cupric oxide formed depends on oxidation temperature

Divergência genética em híbridos de sorgo cultivados sob diferentes níveis de fósforo, em solução nutritiva.

Os objetivos deste trabalho consistiram em identificar a presença de diversidade genética entre acessos de sorgo, em diferentes condições de disponibilidade de P, em solução nutritiva, e determinar quais as características que mais contribuíram para a discriminação dessa divergência. O experimento foi conduzido em casa-de-vegetação, num arranjo fatorial 9x4, sendo nove híbridos de sorgo e quatro doses de P (3, 32, 97 e 129 µM de P.L-1 de solução nutritiva), sob delineamento em blocos ao acaso, com três repetições. Os dados foram submetidos à análise de variância e, posteriormente, ao estudo de dissimilaridade genética, utilizando a matriz de distância generalizada de Mahalanobis e a contribuição relativa das características para a divergência, pelo método de Singh (1981). Concluiu-se que a dose de 3 µM de P.L-1 de solução apresentou valores discrepantes dos demais, sendo desconsiderados seu valores para análise de variância conjunta. Diferenças significativas para todas as características avaliadas foram observadas entre os híbridos, nas doses de P analisadas (32, 97 e 129 µM de P.L-1 de solução nutritiva). A concentração de 97 µM de P.L-1 gerou o maior número de grupos de genótipos. Entretanto, variabilidade genética foi observada também nas demais doses de P. Sob as concentrações de P avaliadas, verificou-se que a característica massa seca total foi a que mais contribuiu para a expressão da dissimilaridade genética entre os híbridos. O híbrido experimental 0735019 apresentou eficiência e responsividade a utilização de P, demonstrando os maiores valores para as características avaliadas nos diferentes níveis de P estudados

The UK's Global Health Respiratory Network: Improving respiratory health of the world's poorest through research collaborations.

Respiratory disorders are responsible for considerable morbidity, health care utilisation, societal costs and approximately one in five deaths worldwide [1-4]. Yet, despite this substantial health and societal burden – which particularly affects the world’s poorest populations and as such is a major contributor to global health inequalities – respiratory disorders have historically not received the policy priority they warrant. For example, despite causing an estimated 1000 deaths per day, less than half of the world’s countries collect data on asthma prevalence (http://www.globalasthmareport.org/). This is true for both communicable and non-communicable respiratory disorders, many of which are either amenable to treatment or preventable

The comparison of outcomes from tyrosine kinase inhibitor monotherapy in second- or third-line for advanced non-small-cell lung cancer patients with wild-type or unknown EGFR status

Background: Second-line treatment for advanced non-small-cell lung cancer (NSCLC) patients includes monotherapy with a third-generation cytotoxic drug (CT) or a tyrosine kinase inhibitor (TKI). These options are the actual standard for EGFR wild-type (WT) status, as patients with EGFR mutations achieve greater benefit by the use of TKI in first-line treatment. Some clinical trials and meta-analyses investigated the comparison between CT and TKI in second-line, but data are conflicting. Methods: We designed a retrospective trial to gather information about TKI sensitivity in comparison with CT. We selected from clinical records patients treated with at least 1 line of CT and at least 1 line of TKI. We collected data about age, sex, performance status, comorbidity, smoking status, histotype, metastatic sites, EGFR status, treatment schedule, better response and time-to-progression (TTP) for each line of treatment and overall survival (OS). Results: 93 patients met selection criteria. Mean age 66,7 (range: 46-84). M/F ratio is 3:1. 39 EGFR-WT and 54 EGFR-UK. All patients received erlotinib or gefitinib as second-line treatment or erlotinib as third-line treatment. No TTP differences were observed for both second-line (HR:0,91; p = 0,6333) and third-line (HR:1.1; p = 0,6951) treatment (TKI vs CT). A trend of a benefit in OS in favor of 3rd-line TKI (HR:0,68; p = 0,11). Conclusions: This study explores the role of TKIs in EGFR non-mutated NSCLC patients. OS analysis highlights a trend to a benefit in patients who received TKI in third-line, even if this result is statistically non-significant. Further analysis are needed to find an explanation for this observation