Hybrid Search: Effectively Combining Keywords and Semantic Searches

This paper describes hybrid search, a search method supporting both document and knowledge retrieval via the flexible combination of ontologybased search and keyword-based matching. Hybrid search smoothly copes with lack of semantic coverage of document content, which is one of the main limitations of current semantic search methods. In this paper we define hybrid search formally, discuss its compatibility with the current semantic trends and present a reference implementation: K-Search. We then show how the method outperforms both keyword-based search and pure semantic search in terms of precision and recall in a set of experiments performed on a collection of about 18.000 technical documents. Experiments carried out with professional users show that users understand the paradigm and consider it very powerful and reliable. K-Search has been ported to two applications released at Rolls-Royce plc for searching technical documentation about jet engines

Identification of onosma visianii roots extract and purified shikonin derivatives as potential acaricidal agents against tetranychus urticae

There is an increasing need for the discovery of reliable and eco-friendly pesticides and natural plant-derived products may play a crucial role as source of new active compounds. In this research, a lipophilic extract of Onosma visianii roots extract containing 12% of shikonin derivatives demonstrated significant toxicity and inhibition of oviposition against Tetranychus urticae mites. Extensive chromatographic separation allowed the isolation of 11 naphthoquinone derivatives that were identified by spectral techniques and were tested against Tetranychus urticae. All the isolated compounds presented effects against the considered mite and isobutylshikonin (1) and isovalerylshikonin (2) were the most active, being valuable model compounds for the study of new anti-mite agents

Fixation of genetic variation and optimization of gene expression: The speed of evolution in isolated lizard populations undergoing Reverse Island Syndrome

The ecological theory of island biogeography suggests that mainland populations should be more genetically divergent from those on large and distant islands rather than from those on small and close islets. Some island populations do not evolve in a linear way, but the process of divergence occurs more rapidly because they undergo a series of phenotypic changes, jointly known as the Island Syndrome. A special case is Reversed Island Syndrome (RIS), in which populations show drastic phenotypic changes both in body shape, skin colouration, age of sexual maturity, aggressiveness, and food intake rates. The populations showing the RIS were observed on islets nearby mainland and recently raised, and for this they are useful models to study the occurrence of rapid evolutionary change. We investigated the timing and mode of evolution of lizard populations adapted through selection on small islets. For our analyses, we used an ad hoc model system of three populations: wild-type lizards from the mainland and insular lizards from a big island (Capri, Italy), both Podarcis siculus siculus not affected by the syndrome, and a lizard population from islet (Scopolo) undergoing the RIS (called P. s. coerulea because of their melanism). The split time of the big (Capri) and small (Scopolo) islands was determined using geological events, like sea-level rises. To infer molecular evolution, we compared five complete mitochondrial genomes for each population to reconstruct the phylogeography and estimate the divergence time between island and mainland lizards. We found a lower mitochondrial mutation rate in Scopolo lizards despite the phenotypic changes achieved in approximately 8,000 years. Furthermore, transcriptome analyses showed significant differential gene expression between islet and mainland lizard populations, suggesting the key role of plasticity in these unpredictable environments

Microwave-Assisted Treatment of Waste Wood Biomass with Deep Eutectic Solvents

Abstract. The increasing depletion of fossil feeds and the environmental concerns linked to the use of traditional energy sources have stimulated both academic and industrial worlds in exploiting new sustainable and renewable suppliers of raw materials [1]. In this framework, lignocellulosic biomass can play an important role, acting as the starting material of a biorefinery leading to biofuels, chemicals, and other value-added products, commonly obtained from petroleum. Recently, numerous protocols for processing lignocellulosic biomass of selected plants have been reported. However, developing an environment-friendly method is still a big goal. This challenge becomes more interesting if lignocellulosic biomass coming from wood wastes could be efficiently treated. Deep eutectic solvents (DESs) are new sustainable and cheap reaction media, combining the features of ionic liquids and organic solvents. They are made by association of hydrogen-bond donors and hydrogen-bond acceptors, and they can promote the hydrolysis of lignocellulosic bonds [2]. Herein, we report on the microwave-assisted treatment of waste wood flours with DESs formed by choline chloride and oxalic acid to get a cellulosic residue separated from lignin degradation products, identified by NMR spectroscopy. The insoluble deposit was characterized by SEM, TGA, DSC, FTIR-ATR and 13C CP/MAS NMR techniques and could be available for further uses such as nanocellulose production. [1] Haldar D., Purkait M.K. Chemosphere 2021, 128523. [2] Liu S., Zhang Q., Gou S., Zhang L., Wang Z. Carbohydr. Polym. 2021, 251, 11701

Applying semantic web technologies to knowledge sharing in aerospace engineering

This paper details an integrated methodology to optimise Knowledge reuse and sharing, illustrated with a use case in the aeronautics domain. It uses Ontologies as a central modelling strategy for the Capture of Knowledge from legacy docu-ments via automated means, or directly in systems interfacing with Knowledge workers, via user-defined, web-based forms. The domain ontologies used for Knowledge Capture also guide the retrieval of the Knowledge extracted from the data using a Semantic Search System that provides support for multiple modalities during search. This approach has been applied and evaluated successfully within the aerospace domain, and is currently being extended for use in other domains on an increasingly large scale

Structure/activity virtual screening and in vitro testing of small molecule inhibitors of 8-hydroxy-5-deazaflavin:NADPH oxidoreductase from gut methanogenic bacteria

Virtual screening techniques and in vitro binding/inhibitory assays were used to search within a set of more than 8,000 naturally occurring small ligands for candidate inhibitors of 8-hydroxy-5-deazaflavin:NADPH oxidoreductase (FNO) from Methanobrevibacter smithii, the enzyme that catalyses the bidirectional electron transfer between NADP+ and F420H2 during the intestinal production of CH4 from CO2. In silico screening using molecular docking classified the ligand-enzyme complexes in the range between − 4.9 and − 10.5 kcal/mol. Molecular flexibility, the number of H-bond acceptors and donors, the extent of hydrophobic interactions, and the exposure to the solvent were the major discriminants in determining the affinity of the ligands for FNO. In vitro studies on a group of these ligands selected from the most populated/representative clusters provided quantitative kinetic, equilibrium, and structural information on ligands’ behaviour, in optimal agreement with the predictive computational results

Trace Elements in Chromian Spinels from Four Siberian Kimberlites

We analysed the major, minor and trace elements chemistry of forty-two Cr-spinels from four Siberian kimberlites. They showed a wide range in Mg# (Mg/(Mg + Fe2+); 0.42–0.78) and Cr# (Cr/(Cr + Al); 0.32–0.92) and a common trend of increasing Cr# with decreasing Mg#. The major element classification schemes suggested that there were spinels deriving from a peridotitic source (Xen) and spinels crystallised from kimberlitic melts (Chr). Laser-Ablation Inductively Coupled Plasma Mass Spectrometry on both groups showed that the trace elements with the highest abundance were Mn (985–3390 ppm), Ni (531–3162 ppm), V (694–2510 ppm) and Zn (475–2230 ppm). Testing the effectiveness of trace elements in determining the source for Cr-spinels, we found out that Cr-spinels crystallised directly from a kimberlitic melt usually showed higher Mn, Ni, Sc and V concentrations with respect to those of peridotitic origin. In addition, using the available partitioning models, we found that the correlations between major elements and Ni, Co, Sc and Ga in the Xen group could be explained by subsolidus equilibration between spinel, olivine and clinopyroxene at 800–1000 °C, thus supporting a peridotitic source for this group. Finally, we calculated the composition of the possible melts in equilibrium with the Cr-spinels of the Chr group, using a selected set of partition coefficients. Calculated abundances of Cu, Ga and Zr were comparable to those of the kimberlite, while V was never close to the kimberlite composition. This simulation highlighted the need for new data on the trace elements partition coefficients between kimberlitic melts and Cr-spinel

Isofuranodiene, a natural sesquiterpene isolated from wild celery (Smyrnium olusatrum L.), protects rats against acute ischemic stroke

The myrrh-like furanosesquiterpene isofuranodiene (IFD) is the main constituent of wild celery (Smyrnium olusatrum L., Apiaceae), an overlooked vegetable that was cultivated during the Roman Empire. In the present study, we investigated the protective effects of IFD pre-treatment against oxidative stress and inflammatory response in an animal model of ischemic stroke. IFD was isolated by the crystallization of Smyrnium olusatrum essential oil, and its structure and purity were confirmed by NMR and HPLC analyses. Acute pre-treatment of IFD (10 mg/kg i.p.) significantly reduced the levels of the inflammatory cytokines IL-1β and TNF-α, the expression of pNF-κB/NF-κB, and the lipid peroxidation indicator MDA. Finally, IFD boosted a faster recovery and better scores in grid-walking and modified neurological severity scores (mNSS) tests. Taken together, these findings indicate IFD as a promising lead compound for the discovery of new treatments of brain ischemia

Assessing repeatability and reproducibility of Anterior Active Rhinomanometry (AAR) in children

BACKGROUND: Repeatability and reproducibility are essential for clinicians for several purposes. Although discouraged, use of the Coefficient of Variation (CV) for assessing repeatability and reproducibility, rather than the Intraclass Correlation Coefficient (ICC), is still widespread. The aim of the present study was to highlight how using inappropriate indices may lead to misleading results, and this is done by simulation study and using real data on Anterior Active Rhinomanometry (AAR) in both healthy children and ones with rhinitis. METHODS: A simulation study was carried out to highlight how using inappropriate indices could be misleading. Then a comparison was made between CV and ICC to assess repeatability and reproducibility of AAR, for which previous studies have given underestimated results. AAR is recommended as the gold standard tool for measuring nasal resistance in clinical practice. RESULTS: A simulation study showed that the ICCs estimated from data generated assuming a true CV yielded results in agreement with estimated CVs; by contrast, if data were generated assuming a true ICC, CVs yielded conflicting results. For AAR, ICCs showed good repeatability, whereas CVs showed unacceptable repeatability. AUC and 95% CI for AAR showed good performance in predicting current symptoms of rhinitis in the overall study population. CONCLUSIONS: The present study focused on the importance of the choice of appropriate indices of repeatability and reproducibility, demonstrating the repeatability of AAR in both healthy children and ones with rhinitis