1,591 research outputs found
May a standard VOF numerical simulation adequately complete spillway laboratory measurements in an operational context? The case of Sa Stria Dam
The present work aims to assess whether a standard numerical simulation (RANS-VOF
model with k e closure) can adequately model experimental measurements obtained in a dam
physical model. The investigation is carried out on the Sa Stria Dam, a roller compacted concrete
gravity dam currently under construction in Southern Sardinia (Italy). The original project, for which
a physical model was simulated, included a downstream secondary dam. However, due to both
economic and technical reasons, the secondary dam may not be built. Hence, it is important to
assess the flood discharge routing and energy dissipation in the modified plan. Numerical validation
is performed adopting the same laboratory configuration, in presence of the downstream dam,
and results show a good agreement with mean experimental variables (i.e., pressure, water level).
An alternative configuration without the downstream dam is here numerically tested to understand
the conditions of flood discharge and assess whether its results can give relevant information for
the design of mitigation measures. The topic is of interest also from a more general perspective.
Indeed, the feasibility to integrate numerical models with existing laboratory measurements can
be very useful not only for new constructions but also for existing dams, which may need either
maintenance or upgrading works, such as in case of flood discharge increment
Pseudococcus affinis MASK., new vector of grapevine trichoviruses A and B
Research Note
Grapevine trichovirus A (GVA) and grapevine trichovirus B (GVB) were successfully transferred with bulk transmission trials under controlled conditions, from infected grapevines to herbaceous hosts by Pseudococcus affinis MASK., a pseudococcid mealybug that may attack grapevines. P. affinis is the fourth mealybug species capable of vectoring GVA and GVB, confirming that transmission by mealybugs of grapevine trichoviruses may not be species-specific
On the possible relationship between Kober stem grooving and grapevine virus A
Investigations were carried out to establish possible correlations of two diseases of the rugose wood complex, i.e. Rupestris stem pitting (RSP) and Kober stem grooving (KSG) with grapevine virus A (GVA) and grapevine leafroll associated viruses I (GLRaV I) and III (GLRaV III). To this purpose 84 clonal accessions of different wine grape cultivars were analyzed by ELISA and by indexing onto the indicators Vitis rupestris, Kober 5BB and LN 33. The results obtained clearly indicated that none of the viruses taken into consideration is apparently involved in the etiology of RSP. Conversely, a remarkably close association of GVA with KSG was discovered
Analysis of hybrid separation schemes for levulinic acid separation by process intensification and assessment of thermophysical properties impact
From the time levulinic acid was listed as one of the top-12 building blocks for the sugars-high value compounds conversion, the interest in this compound increased. As part of its possible production route, the definition of viable separation schemes appears of paramount importance in the overall development of levulinic acid exploitation. Hybrid sequences where liquid-liquid extraction is followed by distillation were considered proving how the direct and direct-indirect separation schemes appeared to be the best alternatives in terms of total annual cost and environmental impact. These alternatives were further analyzed to improve their design by complementing the process simulator database with thermophysical experimental values. After obtaining a reliable design for the hybrid direct and direct-indirect configurations used as benchmarks, two intensified al-ternatives were generated. The first intensified configuration is classified as thermodynamically equivalent sequence, while the second one includes a divided wall column. For both, it was achieved a reduction of the total annual cost of 11% without any penalty for the environmental impact compared to the reference case
Photographic detection of Cadmium(II) and Zinc(II) ions
The binding properties of two 2,8-dithia-5-aza-2,6-pyridinophane-based ligands, bearing respectively coumarin (HNCum) and naphthol-benzoxaazole (HNBO) optically active units as pendant arms, were studied with the aim of transition metal cations selective detection. The novel all-solid-state optodes were obtained by inclusion of fluorophores inside PVC-based polymeric films. The influence of lipophilic sites incorporation and plasticizer nature on pyridinophane-based optodes response was investigated. An enhanced selectivity of the ligands towards Cadmium(II) and Zinc(II) ions was detected. Light Emitting Diode, LED 380 nm, was used as light source, and a digital camera as a signal detector. The results obtained demonstrated the suitability of the developed optodes to perform fast and low cost simultaneous monitoring of Zn2+and Cd2+ ions by means of familiar devices and chemometrics. © 2016 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license
Production of monoclonal antibodies to Grapevine virus D and contribution to the study of its aetiological role in grapevine diseases
Six stable hybridoma cell lines secreting monoclonal antibodies (MAbs) to Grapevine virus D (GVD) were obtained by fusing spleen cells of immunized BALB/c mice with mouse myeloma cell line Sp 2/0-Ag 14, In ELISA all MAbs detected the virus in Nicotiana leaf extracts or cortical shavings from mature grapevine canes, The use of a polyclonal antiserum for coating plates and of monoclonal antibodies and antimouse-conjugated antibodies for antigen detection, gave highly efficient and reproducible results for identification of GVD in field-grown grapevines. The reliability of the ELISA kit was confirmed by GVD-transmission tests to herbaceous hosts, using in vitro explants as inoculum, 223 vines affected by one or more of the 4 syndroms of the rugose wood complex (Kober stem grooving, Corky bark, LN stem grooving and Rupestris stem pitting) were tested in ELISA for the detection of Grapevine virus A (GVA), Grapevine virus B (GVB) and GVD and by Western blot for the detection of Grapevine rupestris stem pitting associated virus (GRSPaV). The possible cause-effect relationship between GVA and KSG, GVB and Co, and GRSPaV and RSP was confirmed, but no consistent association was found between GVD and any of the 4 above syndromes, Intriguingly, a reduction in the expression of stem pitting symptoms in V. rupestris (from 90 % to 75 %) and of stem grooving symptoms in Kober 5BB (from 95 % to 70 %) was observed when vitiviruses and GRSPaV were contemporarily present in the same indicator. Preliminary data of a survey involving 676 grapevine samples showed a high incidence (31 %) of GVD, regardless of the geographical origin of samples.
The Italian Family Satisfaction in the Intensive Care Unit Questionnaire: A Psychometric Evaluation Using the Rasch Model
Quality measurement of the intensive care unit (ICU) should include families’ perspectives, their satisfaction with the care process and outcomes, and the evaluation of actions to improve their psychological health and wellbeing. The current study was designed to validate the Italian version of the Family Satisfaction in the Intensive Care Unit (FS-ICU) using the Rasch model. Results included reliability and separation for items and persons, item fit statistics, unidimensionality, and item characteristic curve. The study was conducted between August 2022 and February 2023. A total of 108 family members (mean age 54.9 years) completed the FS-ICU questionnaire. The instrument had a moderate discrimination ability and only five items (#21, #23, #10, #22, and #24) exhibited a misfit. The Rasch dimension explained 52.1% of the variance in the data, while the unexplained variance in the first contrast is 7.2%, which indicates a possible second dimension. FS-ICU was shown to be beneficial as an assessment instrument for family member satisfaction in the ICU, despite some flaws that need to further be addressed to improve the scale
Reactivity of the drug methimazole and its iodine adduct with elemental zinc
The reactivity of zinc complexes with N,S-donor molecules may be of relevance to the study of Zn-metalloproteins and -metalloenzymes. In this context, the zinc complex [Zn(MeImSH)2I2] was synthesised by the reaction of zinc powder with the 1 : 1 iodine adduct of the drug methimazole [(MeImSH)·I2]. The molecular structure of the complex, elucidated by X-ray diffraction analysis, showed a tetrahedral zinc(II) centre coordinated by two neutral methimazole units (through the sulfur atoms) and two iodides. From the reaction of MeImSH and Zn powder, the complex [Zn(MeImSH)(MeImS)2] (MeImS = deprotonated form of methimazole) was separated and characterised. An analysis of the crystal packing of the neutral complexes [Zn(MeImSH)2X2] (X = I, Br and Cl) and the ionic complex [Zn(MeImSH)3I]I showed that in all of the complexes the sulfur atom, in addition to binding to the metal centre, contributes to the formation of 1-D chains built via C(4)–HS and N–HX interactions in the neutral complexes, and via C(4)–HS and N–CH3S interactions in the ionic complex [Zn(MeImSH)3I]I. The deprotonation/protonation of the coordinated methimazole units can modulate the coordination environment at the Zn core. From the reaction of complex [Zn(MeImSH)3I]I with a strong non-coordinating organic base, we have shown that, as a consequence of the NH deprotonation of methimazole S-coordinated to zinc(II), the ligand coordination mode changes from S-monodentate to N,S-bridging. Correspondingly, in the complex [Zn(MeImSH)(MeImS)2], the MeImS that displays the N,S-bridging mode at zinc can be N-protonated and thereby changes to the S-monodentate coordination
Mediating Performance Through Virtual Agents
This paper presents the process of creation of virtual agents used in a virtual reality performance. The performance aimed to investigate how drama and performance could inform the creation of virtual agents and also how virtual reality could raise questions for drama and performance. The virtual agents were based on the performance of 2 actors. This paper describes the process of preparing the actors, capturing their performances and transferring them to the virtual agents. A second set of agents was created using
non-professional 'naive performers' rather than actors
- …