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The paper aims to introduce a multigroup approach to assess group effects in quantile regression. The procedure estimates the same regression model at different quantiles, and for different groups of observations. Such groups are defined by the levels of one or more stratification variables. The proposed approach exploits a computational procedure to test group effects. In particular, a bootstrap parametric test and a permutation test are compared through artificial data taking into account different sample sizes, and comparing their performance in detecting low, medium, and high differences among coefficients pertaining different groups. An empirical analysis on MOOC students' performance is used to show the proposal in action. The effect of the two main drivers impacting on performance, learning and engagement, is explored at different conditional quantiles, and comparing self-paced courses with instructor-paced courses, offered on the EdX platform. [ABSTRACT FROM AUTHOR]

Since their inception, velocity map imaging (VMI) techniques have received continued interest in their expansion from 2D to 3D momentum measurements through either reconstructive or direct methods. Recently, much work has been devoted to the latter of these by relating electron time-of-flight (TOF) to the third momentum component. The challenge is having a timing resolution sufficient to resolve the structure in the narrow (<10 ns) electron TOF spread. Here, we build upon the work in VMI lens design and 3D VMI measurement by using a plano–convex thick-lens (PCTL) VMI in conjunction with an event-driven camera (TPX3CAM) providing TOF information for high resolution 3D electron momentum measurements. We perform simulations to show that, with the addition of a mesh electrode to the thick-lens geometry, the resulting plano–convex electrostatic field extends the detectable electron cutoff energy range while retaining the high resolution. This design also extends the electron TOF range, allowing for a better momentum resolution along this axis. We experimentally demonstrate these capabilities by examining above-threshold ionization in xenon, where the apparatus is shown to collect electrons of energy up to ∼7 eV with a TOF spread of ∼30 ns, both of which are improved compared to a previous work by factors of ∼1.4 and ∼3.75, respectively. Finally, the PCTL-VMI is equipped with a coincident ion TOF spectrometer, which is shown to effectively extract unique 3D momentum distributions for different ionic species in a gas mixture. These techniques have the potential to lend themselves to more advanced measurements involving systems where the electron momentum distributions possess non-trivial symmetries. [ABSTRACT FROM AUTHOR]

The study of nanomaterials is an active area of research for technological applications as well as fundamental science. A common method for studying properties of isolated nanoparticles is by an in-vacuum particle beam produced via an aerodynamic lens. Despite being common practice, characterization of such beams has proven difficult as light scattering detection techniques fail for particles with sizes beyond the diffraction limit. Here we present a new technique for characterizing such nanoparticle beams using strong field ionization. By focusing an ultrafast, mJ-level laser into the particle beam, a nanoparticle within the laser focus is ionized and easily detected by its ejected electrons. This method grants direct access to the nanoparticle density at the location of the focus, and by scanning the focus through the transverse and longitudinal profiles of the particle beam we attain the 3-dimensional particle density distribution for a cylindrically symmetric beam. Further, we show that strong field ionization is effective in detecting spherical nanoparticles as small as 10 nm in diameter. Additionally, this technique is an effective tool in optimizing the particle beam for specific applications. As an example we show that the particle beam density and width can be manipulated by restricting the gas flow into the aerodynamic lens. [ABSTRACT FROM AUTHOR]

Quantile composite-based path modeling is a recent extension to the conventional partial least squares path modeling. It estimates the effects that predictors exert on the whole conditional distributions of the outcomes involved in path models and provides a comprehensive view on the structure of the relationships among the variables. This method can also be used in a predictive way as it estimates model parameters for each quantile of interest and provides conditional quantile predictions for the manifest variables of the outcome blocks. Quantile composite-based path modeling is shown in action on real data concerning well-being indicators. Health outcomes are assessed taking into account the effects of Economic well-being and Education. In fact, to support an accurate evaluation of the regional performances, the conditions within the outcomes arise should be properly considered. Assessing health inequalities in this multidimensional perspective can highlight the unobserved heterogeneity and contribute to advances in knowledge about the dynamics producing the well-being outcomes at local level. [ABSTRACT FROM AUTHOR]

Massive Open Online Courses, universally labelled as MOOCs, become more and more relevant in the era of digitalization of higher education. The availability of free education resources without access restrictions for a plenty of potential users has changed the learning market in a way unthinkable only few decades ago. This form of web-based education allows to track all the actions of the students, thus providing an information base to understand how students' behaviour can influence their performance. The paper proposes a structural equation model in the framework of the component-based approach to measure which are the main factors affecting students' performance (Partial Least Squares Path Modelling). The novelty of the approach is the simultaneous analysis of more than one factor that exerts an impact on the performance. The analysis is carried out on the log data of a course available on the edX MOOCs platform named FedericaX. [ABSTRACT FROM AUTHOR]

This article proposes a quantitative analysis to measure social vulnerability in a urban space, specifically in the area of the Municipality of Rome. Social vulnerability can be defined as a situation in which people are characterized by a condition of multidimensional deprivation that encompasses multiple aspects of life and exposes population to different risks and hazards produced by natural, environmental, socioeconomic and epidemic factors. The analysis that follows presents the use of multivariate methods and models to provide an index for every dimensions of vulnerability (housing quality, social context, education, employment, urban mobility, social relations and economic conditions) and a global index for mapping social vulnerability. The analysis also succeeds in identifying significant vulnerability spatial patterns and to measure how and if vulnerability can be different in case of an observed heterogeneity in urban space. [ABSTRACT FROM AUTHOR]

A force-driven kinetic energy harvester, designed to be excited with impulse-like mechanical loads, is presented. Energy harvesting is a promising technique to feed wireless sensor networks. The proposed device exploits three rods of Galfenol and has been modeled through FEM COMSOL Multiphysics with nonlinear fully coupled characteristics. They consider the general behaviors of magnetostrictive materials and are compatible with thermodynamics. The preliminary results of the time-domain simulations, with an impulse-like force applied, have been compared with experimental results showing a good agreement. Moreover, the proposed nonlinear modeling has shown better performances with respect to software built-in magnetostrictive models. At the same time, further modeling improvements seem to be needed in the future to better fit the harmonic content of the free evolution of the device. [ABSTRACT FROM AUTHOR]

The conversion-alloying compounds have been identified as promising anode materials for sodium ion batteries (SIBs). One of them, SnO2, with an enormous theoretical capacity of 1558 mAh g−1 is an interesting candidate, also due to its low cost, environmental friendliness and wide availability of tin. However, many drawbacks limit its application in commercial batteries. In this paper, SnO2 has been synthesized from cheap reagents by using simple and easily scalable coprecipitation synthesis routes obtaining nanoparticles with sizes between 2 and 14 nm with almost spherical morphologies. The reasons of the failure of the alloying/de-alloying process were investigated by combining the results obtained from common electrochemical techniques, providing useful examples for the investigation of every material with analogous electrochemical features. Thanks to cyclic voltammetry, different reaction paths were detected for the two samples. The first cycle irreversibility was well characterized with electrochemical impedance spectroscopy, showing interesting trends in the values of the resistance. Galvanostatic cycling with potential limitations was employed to quantify the irreversibility, finding out that the most crystalline sample reached the terminal phase in the Sn-Na system (Na15Sn4), while the least crystalline sample could not achieve such a result (Na3Sn). The crystallinity of SnO2 was determined to be a key parameter, often neglected, for the realization of satisfactory anode compounds. [ABSTRACT FROM AUTHOR]

Background: Masticatory function of institutionalised elders and its relationship with nutrition and oral health–related quality of life (OHRQoL) are unknown. Objectives: This multicentre cross‐sectional study evaluated the influence of the presence of teeth and dentures on masticatory function (masticatory performance and swallowing threshold) in institutionalised elders. Correlation of masticatory function with nutrition and OHRQoL was also verified. Methods: Older adults (n = 344; mean age (SD) = 77.70 (9.10)), selected from nursing homes in two Brazilian cities, were classified as edentulous with or without complete dentures (CDs), and partially dentate with or without prosthesis. Masticatory performance was assessed using a two‐colour chewing gum. Swallowing threshold was set by the number of chewing cycles performed until swallowing 3.7 g of peanuts. Nutrition was screened by Mini‐Nutritional Assessment—Short Form and body composition. OHRQoL was evaluated through Geriatric Oral Health Assessment Index (GOHAI) and Oral Health Impact Profile (OHIP‐14). The Kruskal‐Wallis test and Spearman's correlation were used (α = 0.05). Results: Edentulous elders without CDs had lower masticatory performance than those with CDs and partially dentate with or without prosthesis (P <.05). Swallowing threshold of edentulous elders with CDs and partially dentate with prosthesis was greater than edentulous elders without CDs and partially dentate without prosthesis (P <.05). Masticatory function was not correlated with nutrition. Masticatory performance was correlated (P <.05) with GOHAI (r2 = −.154) and swallowing threshold with GOHAI (r2 =.162) and OHIP‐14 (r2 = −.146). Conclusion: The absence of teeth and dentures negatively affected the masticatory function. Although the masticatory function was not correlated with institutionalised elders' nutrition, their OHRQoL was negatively impacted. [ABSTRACT FROM AUTHOR]

Parameters within hysteresis operators modeling real world objects have to be identified from measurements and are therefore subject to corresponding errors. To investigate the influence of these errors, the methods of Uncertainty Quantification (UQ) are applied. Results of forward UQ for a play operator with a stochastic yield limit are presented. Moreover, inverse UQ is performed to identify the parameters in the weight function in a Prandtl-Ishlinskiĭ operator and the uncertainties of these parameters. [ABSTRACT FROM AUTHOR]

A reexamination of proteins with conserved cysteines and basic amino acids encoded by the 3′-proximal gene of the positive-sense single-stranded RNA of some monopartite filamentous plant viruses has been carried out. The cysteines are involved in a putative Zn-finger domain, which, together with the basic amino acids, form part of the nuclear or nucleolar localization signals. An in-depth study of one of these proteins, p15 from grapevine B virus (GVB), has shown: (i) a three-dimensional structure with four α-helices predicted by two independent in silico approaches, (ii) the nucleolus as the main accumulation site by applying confocal laser microscopy to a fusion between p15 and the green fluorescent protein, (iii) the involvement of the basic amino acids and the putative Zn-finger domain, mapping at the N-terminal region of p15, in the nucleolar localization signal, as revealed by the effect of six alanine substitution mutations, (iv) the p15 suppressor function of sense-mediated RNA silencing as revealed by agroinfiltration in a transgenic line of Nicotiana benthamiana, and (v) the enhancer activity of p15 on viral pathogenicity in N. benthamiana when expressed from a potato virus X vector. In addition, we elaborate on an evolutionary scenario for these filamentous viruses, invoking takeover by a common ancestor(s) of viral or host genes coding for those cysteine-rich proteins, followed by divergence, which would also explain why they are encoded in the 3′-proximal gene of the genomic single-stranded viral RNA. [ABSTRACT FROM AUTHOR]

Lithium‐ion cells encompassing LiPF6 as the lithium salt and high‐voltage (LiNi0.5Mn1.5O4, LNMO) or high‐capacity (LiNi0.8Mn0.1Co0.1O2, NMC811) cathode materials are prone to transition metal (TM) dissolution caused by HF, whose formation is catalyzed by H2O traces. TM ions can shuttle to the anodic compartment, increasing the cell degradation rate. Accordingly, specific self‐healing strategies are helpful to develop scavengers able to eliminate HF and absorb TM ions so avoiding their shuttling. In this work, the fabrication and test of a bi‐functional, autonomous scavenging agent made of Al2O3 particles decorated is reported with chitosan. The nanometric Al2O3 core is a trap for HF by chemical bonding. The chitosan coating is acid‐sensitive, and the opening of such a capping layer is triggered in the presence of even small amounts of HF, leading to an efficient TM ion‐trapping. In addition, chitosan is biocompatible, biodegradable, and abundant, which is relevant for design‐for‐recycling scopes. With ≈200 ppm of water in the electrolyte, 12 wt% of scavenger causes, after 200 cycles at 1C, an increase of capacity retention from 73% to 88% for LNMO, and, impressively, from 46% to 84% for NMC811. This autonomous self‐healing mechanism is promising for application in next‐generation smart cells without requiring any external sensing. [ABSTRACT FROM AUTHOR]

Pepino mosaic virus (Pep MV) is a highly infectious potexvirus that causes a severe disease in tomato ( Solanum lycopersicum) crops worldwide. In Sicily, the first outbreak was detected in a single greenhouse in 2005 and it was promptly eradicated. However, in 2008, a large number of greenhouses were simultaneously affected, and it was impossible to eradicate or control the virus. This study addressed the dispersion and the genetic diversity of Pep MV isolates obtained from the outbreak in Sicily, in comparison with worldwide Pep MV isolates, to gain insight into the factors determining the evolution and epidemiology of the virus. A total of 1800 samples from plants with and without symptoms were collected in the Sicilian provinces of Agrigento, Caltanissetta, Palermo, Ragusa, Siracusa and Trapani. Three isolates collected at different times were biologically characterized. The incidence of the virus increased rapidly from 13% in 2011 to 63% in 2013, and phylogenetic analysis showed that all Sicilian isolates of Pep MV belonged to the CH2 strain, one of the six strains previously described. Nucleotide diversity of the Sicilian isolates was low, thus suggesting rapid spread and genetic stability. [ABSTRACT FROM AUTHOR]

Various new phenomena emerge in quantum materials under elastic deformations, such as hydrostatic or uniaxial stresses. In particular, using uniaxial strain or stress can help to tune or uncover specific structural or electronic orders in materials with multiple coexisting phases. Those phases may be associated with a quantum phase transition requiring a millikelvin environment combined with multiple experimental probes. Here, we describe our unique apparatus, which allows in situ tuning of strain in large samples inside a dilution refrigerator while the samples are monitored via an optical microscope. We describe the engineering details and show some typical results of characterizing superconducting strontium titanate under stress. This letter should serve as a practical reference for experts in ultra-low temperature experimental physics involving uniaxial stresses or strains. [ABSTRACT FROM AUTHOR]

NiZnFe 2 O 4 superparamagnetic nanoparticles were coated with silica by impregnation with tetraethoxysilane (TEOS) and further activated with divinylsulfone (DVS) and p -benzoquinone (BQ) for covalent immobilization lipase from Pseudomonas fluorescens (PFL), producing the biocatalysts TEOS-NANO-DVS-PFL and TEOS-NANO-BQ-PFL. The optimal conditions for enzyme immobilization were found to be pH 7 and 0.1 M of both activating reagents. PFL was also immobilized on TEOS nanoparticles without any activation as a reference (TEOS-NANO-PFL). Results indicated that TEOS could be released from the nanoparticles at alkaline pH value. Optimal TEOS-NANO-PFL exhibited a recovered activity of 55% and a t 1/2(60°C) of just over 150 min; while TEOS-NANO-DVS-PFL showed 82% of activity recovered and t 1/2(60°C) of 225 min; being the TEOS-NANO-BQ-PFL the biocatalyst offering the best results (89% of recovered activity and a half-life over 1440 min), the maximum enzyme load was ≈300 U/g. • NiZnFe 2 O 4 superparamagnetic nanoparticles were coated TEOS and further activated with DVS or BQ. • The support activation has been optimized, the release of TEOS at alkaline pH values become a problem. • PFL has been immobilized on NANO-TEOS, NANO-TEOS-DVS and NANO-TEOS BQ. • Optimal biocatalyst has been obtained by immobilizing PFL on NANO-TEOS BQ at pH 7 for 24 h. • Under stress inactivations, TEOS-NANO-BQ-PFL half live was 24 h while that of TEOS-NANO-PFL was 2.5 h. [ABSTRACT FROM AUTHOR]

This paper analyzes the determinants of stated individual support towards environmental action. The analysis is realized by means of an original Partial Least Squares Path model of Environmental Awareness-Social Capital-Action and it is based on survey data provided in the fifth wave of the World Values Survey (2005–2009) regarding 34.612 individuals from 42 different countries. Besides the global estimates obtained on the whole set of countries, the paper proposes a subsample analysis for developed and developing countries, as well as country analyses for four major economies: China, India, Germany and the United States. We find that environmental awareness and trust in not-for-profit organizations are important determinants of individual action in support of environmentally friendly policies. In general, trust in science and technology does not crowd-out individual support towards the environment. [ABSTRACT FROM AUTHOR]

Magnetostrictive cantilever beams are reliable and straightforward energy harvesting devices for powering wireless sensors using environmental vibrations. However, despite their widespread use, a comprehensive analytical model encompassing both mechanical and electromagnetic main features is still lacking. The mechanical-to-magnetic coupling of a magnetostrictive beam, with its various working conditions and nonlinear characteristics, can be effectively approximated by the Euler–Bernoulli (E–B) equation with damping (viscous and Kelvin–Voigt) coupled with a non-linear magnetostrictive model. In this study, we propose a practical and convenient model for a general concept device designed to convert vibrations into electrical energy. The model is thoroughly compared with experimental measurements aimed to prove the goodness of the approach rather than energy harvesting highest performance. • The Δ E effect of magnetostrictives is considered in the cantilever beam behavior. • A fast and accurate mechanical + magnetomechanical model is provided. • Far lower errors are found with respect to available models in the literature. [ABSTRACT FROM AUTHOR]

This paper deals with a recently proposed device for energy harvesting from environmental vibrations, employing a magnetostrictive material. Even if most of the modeling efforts were focused on a linear approach, more complex and nontrivial phenomena are experimentally observed. A sample of such nontrivial behaviors, suggesting the definition of potentially more effective models, is described and discussed in this paper [ABSTRACT FROM AUTHOR]

In this paper a generalization of a stress-dependent magnetostriction phenomenological model is presented. The model makes use of a classical Preisach operator and of a memoryless bivariate function and includes a pure elastic contribution. It is shown that, even if the structure of the model is simple, the operator state is still influenced by the applied stress. This property is important because the model is able to catch real magnetostrictive behavior in the presence of complex time evolutions of both the variables, current and stress. Experimental and numerical results confirm the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

A model for the description of the energy harvesting in magnetostriction devices is discussed. In particular, the effects of hysteresis, normally observed in these materials, are highlighted and compared to the predictions of the linear modeling. The coupling of the model to the circuit equations leads to a differential equation with hysteresis, which could provide an effective macroscopic description of the energy conversion mechanism taking place in these devices. Numerical tests are performed in order to show the effect of a magnetic field bias on the generated electric power. [ABSTRACT FROM AUTHOR]

An interesting measure for equitable and sustainable well-being has been proposed recently by the National Institute of Statistics in Italy and the National Council for Economy and Labour. It is called BES (from the Italian Benessere Equo e Sostenibile). A set of indicators, partitioned into several domains and themes, is used for measuring the BES. Taking into account prior knowledge of both the structure of this set of indicators and the relationships among them, the paper proposes a hierarchical composite model for measuring and modeling the BES of the Italian provinces. This hierarchical model allows us to synthesize individual indicators into single indexes in order to construct composite indicators at a global and a partial level. Moreover, we analyze the relationships among the different domains and themes as well as the effects of these on equitable and sustainable well-being, in order to search for strongly influential factors. In order to estimate the parameters of the model, we use both Partial Least Squares path modeling and a new method, called Quantile Composite-based path modeling. In particular, Partial Least Squares path modeling is used to estimate average effects in the network of relationships between variables, while with Quantile Composite-based path modeling we investigate whether the magnitude of these effects changes across different parts of the variable distributions, providing a more complete picture and uncovering specific local leveraging factors for improvement. A final ranking of the Italian provinces, according to the BES composite indicator, is also provided at the national level and for different geographic areas of Italy. [ABSTRACT FROM AUTHOR]

The tomato brown rugose fruit virus (ToBRFV) currently represents one of the most significant threats to tomato crop worldwide. Its transmission occurs mainly through contact between plants and infected surfaces, and only one case of mechanical transmission by arthropods has been reported. Here, we aim to assess the role of an invasive tomato pest, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), in ToBRFV transmission. Laboratory tests demonstrated the presence of the ToBRFV in adult moths obtained from larvae developed on ToBRFV-infected plants. Infected adults of T. absoluta were able to infect healthy tomato plants. In order to evaluate whether the occurrence of ToBRFV on T. absoluta adults was internal or external to the pupae, as results of larvae feeding on infected plants, pupae obtained from larvae fed on infected plants were externally disinfected and then analyzed for the presence of ToBRFV by RT-qPCR. Adults obtained from disinfected and not-disinfected pupae were also analyzed. Both adults and pupae were positive for the virus, suggesting its presence in the inner surface of the pupal exuvia. Electron microscopy, western blot analyses and hemolymph bioassay showed the absence of ToBRFV virions and viral coat protein in the hemolymph collected from disinfected pupae, demonstrating that the ToBRFV is not circulative in the progeny of T. absoluta adults obtained from larvae fed in infected plants, but probably adults got contaminated during their emergence, due to virus presence in the inner surface of pupal exuvia. This study demonstrates for the first time that T. absoluta can carry an infectious primary inoculum of ToBRFV, highlighting a potential epidemiological role of T. absoluta in spreading ToBRFV in the field. [ABSTRACT FROM AUTHOR]

Energy harvesting allows the conversion of environmental energy into electrical energy to feed low-power consumption electronics. In particular, this method can be exploited to supply wireless sensors nodes for structural health monitoring (SHM) when the electric network source is not present. Indeed, vibrations induced by vehicle traffic on a bridge could be converted into electrical energy, but suitable devices are needed. This paper presents experimental tests over a device based on three Galfenol rods, where electrical and magnetic parameters are changed and tested with different mechanical sources in order to seek the best performance. [ABSTRACT FROM AUTHOR]

Superparamagnetic iron oxide nanoparticles (Fe 3 O 4 ) were prepared by the co-precipitation method and functionalized with 3-amino-propyltriethoxysilane (APTES) or branched-polyethylenimine (PEI). After that, two parallels methods to immobilize the lipase from Thermomyces lanuginosus (TLL) were performed: the first one by ionic exchange and the second one by covalent attachment after the functionalization of the support with glutaraldehyde (GA). X-ray powder diffraction, magnetometry and infrared spectroscopy analysis were used to characterize the TLL preparations. These analyses showed that all samples presented superparamagnetic properties even after the immobilization procedure. The SPMN (superparamagnetic nanoparticle) @APTES covalent preparation had around 450 min of half-life time at pH 7.0 and 70 °C while that of the free enzyme was 46 min. These biocatalysts were evaluated in the kinetic resolution of rac -1-methyl-2-(2,6-dimethylphenoxy)ethyl acetate in different co-solvents (acetonitrile, isopropanol, ethyl ether and tetrahydrofuran). The best results were for the enzyme/substrate ratio of 2:1, in the presence of the ethyl ether or THF (20% v/v both) at 30 °C during 24 h with the SPMN@PEI-TLL biocatalyst. The conversion attained was 50% and the enantiomeric excess of the product was 99%. The new SPMN support are an excellent strategy to easy recovery of the biocatalyst by applying a magnetic field. [ABSTRACT FROM AUTHOR]

Citrus tristeza virus (CTV) outbreaks were detected in Sicily island, Italy for the first time in 2002. To gain insight into the evolutionary forces driving the emergence and phylogeography of these CTV populations, we determined and analyzed the nucleotide sequences of the p20 gene from 108 CTV isolates collected from 2002 to 2009. Bayesian phylogenetic analysis revealed that mild and severe CTV isolates belonging to five different clades (lineages) were introduced in Sicily in 2002. Phylogeographic analysis showed that four lineages co-circulated in the main citrus growing area located in Eastern Sicily. However, only one lineage (composed of mild isolates) spread to distant areas of Sicily and was detected after 2007. No correlation was found between genetic variation and citrus host, indicating that citrus cultivars did not exert differential selective pressures on the virus. The genetic variation of CTV was not structured according to geographical location or sampling time, likely due to the multiple introduction events and a complex migration pattern with intense co- and re-circulation of different lineages in the same area. The phylogenetic structure, statistical tests of neutrality and comparison of synonymous and nonsynonymous substitution rates suggest that weak negative selection and genetic drift following a rapid expansion may be the main causes of the CTV variability observed today in Sicily. Nonetheless, three adjacent amino acids at the p20 N-terminal region were found to be under positive selection, likely resulting from adaptation events. [ABSTRACT FROM AUTHOR]

Abstract: Cucumber mosaic virus, Tomato spotted wilt virus, Tomato mosaic virus, Tomato chlorosis virus, Pepino mosaic virus, Torrado tomato virus and Tomato infectious chlorosis virus cause serious damage and significant economic losses in tomato crops worldwide. The early detection of these pathogens is essential for preventing the viruses from spreading and improving their control. In this study, a procedure based on two multiplex RT-PCRs was developed for the sensitive and reliable detection of these seven viruses. Serial dilutions of positive controls were analysed by this methodology, and the results were compared with those obtained by ELISA and singleplex versions of RT-PCR. The multiplex and singleplex RT-PCR assays were able to detect specific targets at the same dilution and were 100 times more sensitive than ELISA. The multiplex versions were able to detect composite samples containing different concentrations of specific targets at ratios from 1:1 to 1:1000. In addition, 45 symptomatic tomato samples collected in different tomato-growing areas of Sicily (Italy) were analysed by multiplex RT-PCR, singleplex RT-PCR and commercially available ELISA tests. Similar results were obtained using the RT-PCR techniques, with a higher sensitivity than ELISA, revealing a common occurrence of mixed infections and confirming the presence of these seven virus species in Italy. [Copyright &y& Elsevier]

The genetic variation and evolution of cucumber mosaic virus (CMV) from aromatic, medicinal and ornamental plants in northern Italy was studied by sequence analysis of the movement protein gene and comparison with equivalent sequences of isolates from other countries. Comparison of nonsynonymous and synonymous substitutions suggested that 30% of amino acid sites were under negative selection and only one was under positive selection. Phylogenetic, nucleotide diversity and genetic differentiation analyses suggested that long-distance migration plays a role in the evolution and determination of the genetic structure and diversity of CMV in northern Italy and other areas. [ABSTRACT FROM AUTHOR]

Abstract: Two tomato geminivirus species co-exist in protected crops in Sicily, Tomato yellow leaf curl Sardinia virus (TYLCSV, found in 1989) and Tomato yellow leaf curl virus (TYLCV, found in 2002), and mixed infections have been detected. In a field survey conducted in 2004, the viral intergenic region (IR) was amplified from infected plants, and molecules apparently hybrid between the two species were found, but only in plants where one or both parental species were also present. Two of these hybrids, named 2/2 and 2/5, were isolated and infectious clones were obtained. They were both readily whitefly-transmitted to tomato plants; clone 2/5 produced symptoms typical of TYLCSV and TYLCV, while clone 2/2 produced more severe symptoms, with leaves showing downward curling and rugosity. Sequence analysis showed that both 2/2 and 2/5 are newly generated hybrids, with two recombination sites each. One site, common to both hybrids, is in the stem-loop of the IR. The other is close to the 3′-end of the CP ORF in 2/5 and within the Rep ORF in 2/2. Thus, the 2/2 hybrid virus has a hybrid Rep protein, with the 202 amino-terminal aa from TYLCV and the remaining 155 aa from TYLCSV. Replication assays in leaf disc indicated a lower replicative capacity with respect to parental viruses, a fact that might help to explain why plants infected only by a recombinant have not been found so far. [Copyright &y& Elsevier]

Abstract: Tomato yellow leaf curl disease (TYLCD) is well known in Mediterranean countries, where it has been causing severe losses in tomato crops for decades. Until recently, two viruses (with several isolates) in the genus Begomovirus, family Geminiviridae, have been associated with the epidemics: Tomato yellow leaf curl virus (TYLCV) and Tomato yellow leaf curl Sardinia virus (TYLCSV). However, recombinants between these, such as Tomato yellow leaf curl Malaga virus (TYLCMalV), are spreading, and new methods for detecting all viruses present in the region are needed. By considering all DNA sequences available of viruses causing TYLCD in the Mediterranean basin, a PCR/RFLP protocol was developed that amplifies the intergenic region in a multiplex reaction, followed by digestion with AclI (=Psp1406I) restriction enzyme. This procedure generates an easily recognizable pattern on gels, with DNA fragments of specific size for each virus species and each recombinant: 800bp for TYLCSV, 410bp for TYLCV, 570bp for TYLCMalV and the other detected recombinants, 640bp for hypothetical recombinants of different type. This new method gives, with a single reaction, an overview of the species present in the sample and will be useful for screening the causal agents of TYLCD, as well as in breeding programs for resistance. [Copyright &y& Elsevier]

An unusual virus-like yellow leaf disorder associated with fruit marbling was observed during the winter of 2005 in some greenhouse tomato crops in the province of Ragusa Sicily (Southern Italy). Leaf samples from 250 symptomatic tomato plants were serologically tested by DAS-ELISA technique for 5 viruses: Tomato spotted wilt virus (TSWV), Impatiens necrotic spot virus (INSV), Tobacco mosaic virus (TMV), Cucumber mosaic virus (CMV) and Pepino mosaic virus (PepMV). PepMV was detected in 215 of the samples. The virus was mechanically transmitted to cucumber, wild metel, wild tobacco and 'Rio Grande' tomato. The experimental host range of PepMV-Ragusa differed from that of the PepMV found in Sardinia in 2001, which infected 'Camone' tomato. By applying RT-PCR to 25 PepMV-infected tomato plants, the expected 844 bp DNA fragment for PepMV and the expected 439 bp DNA fragment for Tomato chlororis virus (ToCV) were obtained from all the samples tested. Sequences of the obtained amplicons were used to study the phylogenetic relationships of the viruses with isolates from other countries. Nucleotide sequence alignments showed that the sequence CP-PepMV-Ragusa (Genbank acc. No. DQ 517884) were 99% homologous with both US2 and Spain-Murcia isolates, while those of ToCV-Ragusa (Genbank acc. No. DQ517885) isolate HSP70, were 99% homologous with the Florida isolate, and 98% with the Lebanon isolate. The results proved that the unusual disorder found in greenhouse tomatoes in Sicily can be associated with infections by PepMV and ToCV, reported for the first time in a mixed infection. [ABSTRACT FROM AUTHOR]

Hysteresis of smart devices should be modeled in order to improve the performances and to relieve the control system tasks. Prandtl–Ishlinskiı˘ (PI) and Generalized Prandtl–Ishlinskiı˘ (GPI) hysteresis operators are popular because of their easiness of implementation and of the availability of inverse closed formulas. Nevertheless, PI and GPI are a subset of Preisach model (PM). Therefore, in principle, they are limited in representing hysteretic behaviors with respect to PM. In this paper, a first attempt to study the representation error of GPI with respect to general Preisach hysteretic behavior is presented and evaluated through two numerical experiments. [ABSTRACT FROM AUTHOR]

Piezoelectrics are the most commonly used of the multifunctional smart materials in industrial applications, because of their relatively low cost and ease of use in electric and electronic oriented applications. Nevertheless, while datasheets usually give just small signal quasi-static parameters, their full potential can only be exploited only if a full characterization is available because the maximum stroke or the higher piezo coupling coefficients are available at different electro-mechanical biases, where often small signal analysis is not valid. In this paper a method to get the quasi-static fully coupled characterization is presented. The method is tested on a commercial piezo actuator but can be extended to similar devices. [ABSTRACT FROM AUTHOR]

• BPEI functionalized Fe 3 O 4 NPs enhanced the electron flow in glassy carbon electrodes. • GCE/Fe 3 O 4 @BPEI sensor exhibited great performance in cabendazim sensing. • The developed sensor exhibited a low detection limit of 10 nM for carbendazim. • Carbendazim was successfully detected and quantified in natural waters. • An alternative mechanism for carbendazim electrooxidation was proposed. Functionalized magnetic nanoparticles (MNPs) can boost the performance of electrochemical sensors, increase their sensitivity, and modulate electrode-analyte interactions. In this work we used MNPs functionalized with poly(sodium acrylate) (Fe 3 O 4 @PAANa), trisodium citrate (Fe 3 O 4 @CIT) and branched polyethylenimine (Fe 3 O 4 @BPEI) to modify glassy carbon electrodes (GCE) towards the development of electrochemical sensors. Fe 3 O 4 @BPEI was selected to design an electrochemical sensor for carbendazim (CBZ) once this sample exhibited better performance in the enhancement of the electroactive area of GCE and decrease of the charge transfer resistance. Furthermore, we propose a pathway for the electrooxidation reaction of CBZ based on electrochemical measurements and the oxidation products detected by performing mass spectrometry. Our findings indicated that oxidation of CBZ occurs through the insertion of hydroxyl radicals and that the redox reaction involves the same number of protons and electrons. This electroanalytical methodology using Fe 3 O 4 @BPEI exhibited limit-of-detection and limit-of-quantitation values of 10 and 33 nmol L–1, respectively. Moreover, the proposed sensor exhibited high stability (%RSD = 1.31, n = 7), reproducibility (%RSD = 2.84, n = 5), and anti-interference ability. In addition, an electroanalytical methodology was successfully developed for the detection of CBZ in natural waters. This study presents the potential multidisciplinary application of functionalized MNPs as sensors for quantifying CBZ in natural waters and a likely reaction pathway for the electrochemical oxidation of CBZ. [Display omitted] [ABSTRACT FROM AUTHOR]

The use of embedded computational capabilities in devices with magnetostrictive materials allows the design of objects, able to show smart features without the use of external controllers/devices. However, in the magnetostrictive devices world, the problem of getting smart performances in actuation and sensing, with a lower cost, has been faced a few times to date. In this paper, we present the compensation of the hysteresis of a magnetostrictive actuator using a low-cost Arduino platform (fixed-point mathematic). In this case, a quasi-linear actuator is obtained. The experimental performances are compared with the ones of a standard xpctarget-MATLAB environment (floating point mathematic). We found that the Arduino solution is largely acceptable, dealing with compensation errors within a few percents, and fast enough compensation times, up to sampling frequencies of kilohertz. [ABSTRACT FROM AUTHOR]

The synthesis of a number of single observed indicators into a unique composite indicator involves various subjective choices related, for instance, to the type of combination (linear, non-linear) and to the aggregation method (simple average, geometric average) used in its construction. Thus, it is clearly important to analyse the variability of a composite indicator according to all possible alternatives before employing it in any decision-making process. Within such a framework, in this paper, we present a new approach based on a combination of explorative and confirmative analyses aiming to investigate the impact of different subjective choices on the variability of composite indicators. This new approach also allows the analysis of the related individual differences among the statistical units and the use of external information on the same units to enhance the interpretation of the final results. [ABSTRACT FROM AUTHOR]

Highlights: [•] The paper proposes the use of classification trees in consumer studies. [•] Focus is given to the validation of the results. [•] A comparison of the proposed method with alternatives approaches is provided. [•] Advantages and drawbacks of the new approach are discussed. [ABSTRACT FROM AUTHOR]

In Italy, from January 2021, the Ministry of Health indicated a vaccination plan against COVID for frail patients and physicians based on a three-dose scheme. However, conflicting results have been reported on which biomarkers permit immunization assessment. We used several laboratory approaches (i.e., antibodies serum levels, flow cytometry analysis, and cytokines release by stimulated cells) to investigate the immune response in a cohort of 53 family pediatricians (FPs) at different times after the vaccine. We observed that the BNT162b2-mRNA vaccine induced a significant increase of specific antibodies after the third (booster) dose; however, the antibody titer was not predictive of the risk of developing the infection in the six months following the booster dose. The antigen stimulation of PBMC cells from subjects vaccinated with the third booster jab induced the increase of the activated T cells (i.e., CD4+ CD154+); the frequency of CD4+ CD154+ TNF-α+ cells, as well as the TNF-α secretion, was not modified, while we observed a trend of increase of IFN-γ secretion. Interestingly, the level of CD8+ IFN-γ+ (independently from antibody titer) was significantly increased after the third dose and predicts the risk of developing the infection in the six months following the booster jab. Such results may impact also other virus vaccinations. [ABSTRACT FROM AUTHOR]

Abstract: In vivo toxicity of drug candidates remains a major problem in the pharmaceutical industry, and is a significant cause of late stage attrition. As a consequence predictive in vitro assays are developed and put in place early in the discovery pipeline to aid compound selection. Endoplasmic reticulum stress (ER-stress) has been implicated in many disease states, as well as compound-induced organ toxicities. We explored the role of ER-stress as a general mechanism of toxicity by utilizing a high-throughput in vitro assay to screen 316 chemically diverse Pfizer proprietary compounds with known in vivo toxicity outcome for nuclear accumulation of spliced x-box binding protein 1 (XBP1s), a key transcription factor of the unfolded protein response (UPR). We examined the correlation between physicochemical properties, such as molecular weight, pKA, lipophilicity, topological polar surface area, and passive permeability, as well as target promiscuity, between XBP1s hits and non-hits and found that lipophilicity, target promiscuity and low passive permeability significantly contributed to ER-stress. In addition, we have shown that compounds which cause ER-stress in the form of XBP1s activation at concentrations below 40μM have a more than four times greater chance of causing in vivo toxicity at 10μM plasma exposure. [Copyright &y& Elsevier]

Abstract—This paper deals with the experimental characterization of Galfenol (iron-gallium alloy) and its energy harvesting capabilities. Two rods are considered, one with a stress annealing treatment. The impact on the harvesting performance of magnetic bias, mechanical prestress and termination resistor are considered. Moreover, the performed measurements allow to verify an important feature of the energy conversion of this magneto-mechanical material: the energy harvested loops, in the B–H plane, are confined within the magnetic characteristics at the extrema of the applied stress. This suggests the significance of the static characteristics in the energy conversion process. [ABSTRACT FROM PUBLISHER]

Polymeric foams with embedded magnetic particles is a new class of lightweight systems that could lead to relevant industrial applications both for their enhanced directional passive mechanical properties and for their sensitivity to magnetic field that can be used to control the mechanical behavior. This paper is aimed to present the magnetomechanical properties of this novel class of functionalized lightweight composite materials, based on polymeric matrices and with suitable distributions of magnetosensitive micro-sized particles. The result of the ad hoc magnetic field application during the foaming process is a tailored degree of both structural and functional anisotropy without affecting the morphology of the cells, and the optimization of the reinforcing efficiency along one direction. The induced particle distribution can be then utilized for a real-time control of structural and functional properties under working conditions. [ABSTRACT FROM AUTHOR]

Magnetostrictive actuators are employed for several purposes but, often, the control strategy is strongly affected by their hysteretic behavior. Such issue becomes crucial if dynamic mechanical stress conditions apply. Indeed, the stress must be considered as an additional input. Nevertheless, a compensation scheme with two-input variables can be defined and fruitfully utilized in a suitable invertibility region. In this paper, different control strategies, based on a compensation algorithm able to take into account the applied mechanical stress, are proposed and compared with simpler linear controllers in a real-time setup. Experimental data measured over a magnetostrictive actuator are presented and commented. [ABSTRACT FROM AUTHOR]

The analysis of a passive damper employing smart materials is carried out through the description of a concept device loaded by a vibrating mass. Such a device is able to damp vibration and to produce electric energy (energy harvesting). Its basic properties are described in detail and the relationships between damping features and its physical parameters are shown. The analysis is carried out by a linear modeling at first, while the comparison to its actual behaviour is exploited to justify a more careful study where the material non-linearity is considered. Analytical results on the linear model and the spice numerical analysis of a non-linear model are presented. [ABSTRACT FROM AUTHOR]