404 research outputs found
Identifying conservation priorities when data are scanty: A case study with small mammals in Italy
Combining surveys and on-line searching volumes to analyze public awareness about invasive alien species: a case study with the invasive Asian yellow-legged hornet (Vespa velutina) in Italy
The Asian yellow-legged hornet (Vespa velutina) has been invading Italy since 2013, and it was subjected to management programs to counter its spread and raise awareness about its impacts. We administered a questionnaire to a sample of 358 beekeepers in Italy, asking them about their sources of information on V. velutina and their perception of its potential impacts and severity, compared to other threats to beekeeping. We also explored Internet searching volumes on Google and Wikipedia about V. velutina, to identify seasonal and long-term trends in public awareness. Workshops, journals or bulletins, the Internet and word-of-mouth with colleagues were the primary sources of information about V. velutina. Internet searches peaked during the activity period of the species and increased over time, with thousands of visits to Wikipedia each month. Beekeepers believed V. velutina to affect beekeeping by predating on honey bees (Apis mellifera), paralyzing foraging, reducing honey availability and depleting the winter cluster. Moreover, V. velutina has been deemed a severe threat to beekeeping, similar to other threats like pesticides and the varroa mite (Varroa destructor). Our findings indicate that beekeepers seem to be aware of the potential impacts of V. velutina in Italy, both within and outside of its invaded area, considering it a major threat to beekeeping. Moreover, citizens seem to have become progressively curious about the species. Information campaigns on the Internet and specialized magazines might be helpful to communicate about the impacts of the species, and the need to develop diffused surveillance networks
ESTUDO DA COMPLEMENTARIEDADE DE SISTEMAS DE GESTĂO AMBIENTAL E SISTEMAS DE GESTĂO DA ANĂLISE DE PERIGOS E PONTOS CRĂTICOS DE CONTROLE
In the past few years, food companies have been showing a growing interest in implementing Environment Management Systems (EMS), based on the recommendations of ISO 14001. However, many of these companies have already implanted a food safety system based on HACCP that is regulated in Brazil by the standard NBR 14900. The choice for using similar elements of management systems from NBR 14900 and ISO 14001 may reduce the efforts for implanting an EMS in companies that already have a HACCP-MS, the opposite being also true. The present text will explore the possibilities of these supposed complementarities. In conclusion, 17 elements of ISO 14001 and 24 elements of NBR 14900 are complementary, and only one element of each system cannot be considered equivalent.Empresas do segmento alimentĂcio se interessam cada vez mais em implantar sistemas de gestĂŁo ambiental baseados na norma ISO 14001. Contudo, muitas destas empresas jĂĄ possuem implantado um sistema de segurança de alimentos baseado no APPCC, cuja norma brasileira Ă© a NBR 14900. A utilização dos elementos da norma NBR 14900 e dos conceitos do sistema APPCC, que possam apresentar equivalĂȘncia com a norma ISO 14001, poderĂĄ reduzir os esforços no processo de implantação de um SGA, para empresas que jĂĄ possuem um SGAPPCC implementado, e vice versa. O presente artigo explora estas possibilidades de complementariedade e conclui que 17 requisitos da ISO 14001 sĂŁo equivalentes a 24 requisitos da NBR 14900, e apenas um requisito de cada uma destas Normas nĂŁo pode ser considerado equivalente
Sponges associated with octocorals in the Indo-Pacific, with the description of four new species
FIGURE 27. Size/frequency distribution of anisochela lengths of Mycale (Aegogropila) furcata n. sp.Published as part of Calcinai, Barbara, Bavestrello, Giorgio, Bertolino, Marco, Pica, Daniela, Wagner, Daniel & Cerrano, Carlo, 2013, Sponges associated with octocorals in the Indo-Pacific, with the description of four new species, pp. 1-61 in Zootaxa 3617 (1) on page 44, DOI: 10.11646/zootaxa.3617.1.1, http://zenodo.org/record/24815
Topology optimisation of architected cellular materials from additive manufacturing: Analysis, design, and experiments
This work deals with an experimental/numerical validation of the optimised topologies found through a special density-based topology optimisation (TO) method wherein the topological descriptor, i.e., the pseudo-density field, is represented through a non-uniform rational basis spline (NURBS) hyper-surface. The framework is that of multi-scale TO methods to design architected cellular materials (ACMs). Specifically, in the most general case, the topological variables are defined at the scale of the representative volume element (RVE) of the ACM and at the macroscopic scale of the structure. The transition among scales is performed via a numerical homogenisation scheme based on the strain energy of elements. The proposed formulation exploits the properties of NURBS entities to determine the relationships occurring among the topological variables defined at different scales to correctly state the optimisation problem and to satisfy the hypotheses at the basis of the homogenisation method. Three design cases are considered: in the first one, TO is performed only at the macroscopic scale; in the second one, TO is performed only at the RVE scale; in the last one, TO is performed simultaneously at both scales. Multiple design requirements related to lightness, scale separation condition (to ensure the validity of the results of the homogenisation method) and minimum printable size are included in the problem formulation. Particularly, the last two requirements are implicitly satisfied by controlling the integer parameters of the NURBS entity (describing the pseudo-density field at each scale) without introducing explicit optimisation constraints. The multi-scale TO strategy is applied to a structure made of ACM subject to three-point bending test-like boundary conditions: for each design case, the optimised topology is manufactured through stereo-lithography and a comparison between experimental and numerical results (obtained through non-linear analysis conducted a posteriori on the optimised topology) is performed to assess the effectiveness of the approach
Composites Part C: Open Access
Recently, the necessity of reducing the probability of spread of viruses has fostered the creativity of engineers to develop tools that would allow actions of every-day life to be executed differently. Moreover, the maturity of the Fused Filament Fabrication (FFF) technology and the associated low costs has allowed creative solutions to be produced and used in real-life applications. A distinctive example is represented by the common action of opening a door. Since hands are a typical vector of contamination for viruses such as Coronavirus, hands-free devices aim at making use of the existing structure and kinematic to complete the same action in a different fashion. Typically, the mechanical and manufacturing requirements of these devices include a suitable stiffness-to-mass ratio, a reduced printing time as well as the minimization of supports which need to be removed in a post-printing phase. To tackle all these requirements a dedicated topology optimization (TO) method can be used since the preliminary design phase. Several design requirements of different nature can be included in the problem formulation: mechanical ones, like mass and stiffness, and manufacturing ones, like drawing direction or minimum member size. In this paper, a feasibility study on a hands-free 3D printed door opener has been carried out by means of the Solid Isotropic Material with Penalization (SIMP) method for TO and its CAD-compatible variant, i.e., the SIMP approach reformulated in the framework of non-uniform rational basis spline hyper-surfaces. The aim of the study is to identify optimal solutions to be adapted to a real-case scenario wherein different loading cases and manufacturing constraints are evaluated. Different optimal solutions are obtained, reconstructed to be compatible with CAD environment and the optimized geometry numerically assessed. Finally, the optimal solutions are also evaluated with respect to indicators such as printing time, total filament mass and mass of the supports required by the printing process.Conception et Optimisation de Forme pour la Fabrication Additiv
Electrochemical immunosensing using a nanostructured functional platform for determination of α-zearalanol
We describe an electrochemical immunosensor for the determination of the growth promoter α-zearalanol in bovine serum. The sensing scheme is based on a nanocomposite consisting of gold nanoparticles electrodeposited on multi-walled carbon nanotubes that were modified with poly(vinylpyridine) through in-situ polymerization. The electrodeposition of the gold nanoparticles enlarges the surface available for immobilization of antibodies against α-zearalanol. The nanocomposite film was characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, and cyclic voltammetry. The calibration plot has a linear response in the concentrations range from 0.05 to 50 ng mLâ1, and the detection limit is 16 pg mLâ1. The time required for analysis is 12 min only which compares quite favorably with the time (90 min) required by the conventional ELISA. The method exhibits good selectivity, stability and reproducibility for detecting α-zearalanol in the livestock production.Fil: Regiart, Daniel Matias Gaston. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico San Luis. Instituto de QuĂmica de San Luis; ArgentinaFil: Seia, Marco Abel. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico San Luis. Instituto de QuĂmica de San Luis; ArgentinaFil: Messina, GermĂĄn Alejandro. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico San Luis. Instituto de QuĂmica de San Luis; ArgentinaFil: Bertolino, Franco AdriĂĄn. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico San Luis. Instituto de QuĂmica de San Luis; ArgentinaFil: Raba, Julio. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico San Luis. Instituto de QuĂmica de San Luis; Argentin
Establishing surveillance areas for tackling the invasion of Vespa velutina in outbreaks and over the border of its expanding range
The yellow-legged hornet Vespa velutina is an invasive alien species in many areas of the world. In Europe, it is considered a species of Union concern and national authorities have to establish surveillance plans, early warning and rapid response systems or control plans. These strategies customarily require the assessment of the areas that could be colonised beyond outbreaks or expanding ranges, so as to establish efficient containment protocols. The hornet is spreading through a mix of natural diffusion and human-mediated transportation. Despite the latter dispersion mode is hardly predictable, natural diffusion could be modelled from nest data of consecutive years. The aim of this work is to develop a procedure to predict the spread of the yellow-legged hornet in the short term in order to increase the efficiency of control plans to restrain the diffusion of this species. We used data on the mean distances of colonial nests between years to evaluate the probability of yellow-legged hornet dispersal around the areas where the species is present. The distribution of nests in Italy was mainly explained by elevation (95% of nests located within 521 m a.s.l.) and distance from source sites (previous yearsâ colonies; 95% within 1.4â6.2 km). The diffusion models developed with these two variables forecast, with good accuracy, the spread of the species in the short term: 98â100% of nests were found within the predicted area of expansion. A similar approach can be applied in areas invaded by the yellow-legged hornet, in particular beyond new outbreaks and over the border of its expanding range, to implement strategies for its containment. The spatial application of the models allows the establishment of buffer areas where monitoring and control efforts can be allocated on the basis of the likelihood of the species spreading at progressively greater distances
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