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Lung cancer is the most lethal of all forms of cancer. In this context, minimally invasive diagnostic approaches are replacing more aggressive surgical ones for the diagnosis and staging of lung cancer. Advances in bronchoscopic technology have allowed for safe and increasingly effective tissue diagnosis of lung nodules. On the other hand, most diagnoses are still made in an advanced stage and also in this scenario, bronchoscopic techniques play a central role in diagnosis and staging. In this review, we offer a concise overview of the significant advances in the field of bronchoscopy and to put them into clinical context. We also address current diagnostic challenges associated with sampling central and peripheral lung lesions and make a concise description of laboratory techniques for proper sample handling. In the era of personalized therapies, obtaining adequate specimens is key to provide a specific histologic and molecular diagnosis of lung cancer. The relationship of target therapies with specific histologies and predictive biomarkers has made the handling of biopsies the key factor for success. [ABSTRACT FROM AUTHOR]

Copyright of Rassegna di Patologia dell'Apparato Respiratorio is the property of AIPO - Associazione Italiana Pneumologi Ospedalieri and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Rassegna di Patologia dell'Apparato Respiratorio is the property of AIPO - Associazione Italiana Pneumologi Ospedalieri and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper is concerned with flexural and torsional waves propagation in locally-resonant thin-walled beams with open cross section. A beam with monosymmetric cross section hosting a periodic array of translational and torsional resonators is considered. The resonators are designed to protect the beam from both vertical and lateral dynamic loads; while vertical loads acting in the symmetry plane induce flexural waves only, vertical loads acting out of the symmetry plane and lateral loads induce coupled flexural–torsional waves due to the monosymmetry of the beam cross section. Aim of the paper is to investigate the dispersive properties of the locally-resonant beam under consideration, focusing on coupled flexural–torsional waves. For this purpose, a homogenization approach is adopted to derive a simplified dispersion equation of the infinite locally-resonant beam. Starting from the observation that the latter equation is equivalent to the dispersion equation of a uniform infinite beam with homogenized inertial properties, it is possible to identify the location and the amplitude of band gaps; remarkably, it is found that band gaps for coupled flexural–torsional waves are located in the frequency region where the matrix of the homogenized inertial properties is negative definite. Further, it is demonstrated that band gaps arise when translational and torsional resonators are simultaneously connected to the beam and are tuned to the same frequency; on the other hand, band gaps are not guaranteed if only translational resonators or only rotational resonators are connected to the beam. Alternative exact methods based on the transfer matrix approach and the theory of generalized functions are employed to validate and substantiate the obtained results. • Flexural and torsional waves propagation in locally-resonant thin-walled beams is addressed. • A homogenization approach is adopted to derive a simplified dispersion equation. • Location and amplitude of band gaps are identified employing the concept of effective inertial properties. • The conditions in which band gaps for coupled flexural–torsional waves arise are determined. • Alternative methods are employed to substantiate the results obtained by the homogenization approach. [ABSTRACT FROM AUTHOR]

The bending problem of Euler-Bernoulli discontinuous beams is a classic topic in mechanics. In this paper stepped beams with internal springs are addressed based on the theory of generalized functions. It is shown that in this context a closed-form expression may be given to the Green's functions due to point forces and, based on these, to the beam response to arbitrary loads, for any set of boundary conditions. The proposed solution method may be presented in a regular course in Mechanics of Solids and Strength of Materials for undergraduate students. It does not require an advanced knowledge of the theory of generalized functions but the knowledge of only a few basic concepts, most of which are generally presented in other courses such as, for instance, Dynamics of Structures. It is hoped that it may help students to address in a simple and effective way the many engineering applications involving discontinuous beams. [ABSTRACT FROM AUTHOR]

A theoretical framework is presented to compute the dispersive properties of a locally-resonant Euler–Bernoulli beam hosting a periodic array of beam-like resonators, the bending-torsion response of which may be either uncoupled or coupled depending on the cross-section geometry. It is shown that, in the frequency domain, the reaction of every beam-like resonator can be expressed in an exact analytical form depending only on deflection and rotation of the host beam at the connection points. In this way, the beam-like resonators can be substituted by equivalent fictitious external supports with frequency dependent stiffness. On this basis: (a) band gaps of the infinite locally-resonant beam are easily computed employing a transfer matrix approach; (b) the frequency response, as well as the transmittance of the finite locally-resonant beam, are computed in closed analytical forms extending an efficient formulation recently proposed by the authors, based on generalized functions. In addition to presenting the novel theoretical framework, the main purpose of the paper is promoting coupled bending-torsion beam-like resonators as a novel concept for locally-resonant structures, which may prove even more efficient than conventional uncoupled bending-torsion beam-like resonators. Indeed, it is shown the former offer more and better opportunities to open band gaps, taking advantage of the inherent coupling between bending and torsional vibrations. [Display omitted] • Locally-resonant beam with coupled/uncoupled bending-torsion beam-like resonators. • Resonators reverted to fictitious external supports with frequency dependent stiffness. • Band gaps of infinite beam derived employing a transfer matrix approach. • Exact frequency responses of finite beam computed via generalized function approach. • Coupled bending-torsion beam-like resonators promoted as a novel concept. [ABSTRACT FROM AUTHOR]

This paper focuses on small-size planar beam lattices, where size effects are modelled by the stress-driven nonlocal elasticity theory in conjunction with the Rayleigh beam theory. The purpose is to propose two novel computational approaches for elastic wave propagation analysis. In a first dynamic-stiffness approach, every lattice member is modelled by a unique two-node beam element, the exact dynamic-stiffness matrix of which is built solving, in concise analytical form, the stress-driven differential equations of motion. In a second finite-element approach, every lattice member is discretized by an increasingly refined mesh of two-node beam elements; in this case, the stiffness and mass matrices of the lattice member are obtained from shape functions built based on the exact solutions of the stress-driven differential equations for static equilibrium. Advantages of the two approaches are compared and discussed. Dispersion curves are calculated for a typical planar lattice, highlighting the role of nonlocality. [Display omitted] • Small-size 2D beam lattice modelled by stress-driven nonlocal Rayleigh beam theory. • Elastic wave propagation analysis by dynamic-stiffness or finite-element approaches. • Dynamic-stiffness approach: Unique beam element for lattice member. • Finite-element approach: Nonlocally interacting beam elements for lattice member. • Finite-element results converge to dynamic-stiffness ones for refined meshes. [ABSTRACT FROM AUTHOR]

• Inerter-based resonator absorbers with amplified inertance. • Amplified-inertance absorbers with very high mass ratio. • Analytical calibration procedure still valid for improved device. • Possilbe frequency and damping re-tuning for the proposed absorbers. • Frequency and damping re-tuning without replacing inerter, spring and dashpot. This paper presents improved inerter-based absorbers for vibration mitigation of structural systems. The driving innovative concept is to include a standard inerter-based device within a rhombus truss; specifically, the inerter-based device is connected to the two ends of one diagonal of the rhombus truss and activated by the motion of the structural system along the other diagonal. It is shown that, in this manner, a significant amplification of the inertance can be attained, depending on the diagonal ratio of the rhombus truss. The concept is presented for three typical inerter-based absorbers existing in the literature. The performances of the improved inerter-based devices are investigated and compared thoroughly, as applied to single-degree-of-freedom systems. The optimal tuning is implemented following a well-established procedure, entirely analytical, which makes the design of the improved inerter-based devices very straightforward. A further novelty, particularly appealing for design purposes, is that the improved inerter-based absorbers can be re-tuned over a certain frequency range by changing only the geometry of the rhombus truss, with considerable benefits in those cases where the structural system parameters may vary during the operational lifetime. For completeness, an application to a multi-degree-of-freedom system substantiates the effectiveness of the proposed concept. [ABSTRACT FROM AUTHOR]

Triply-coupled bending-torsion in beams with asymmetric cross section is an interesting yet challenging problem in dynamics. In this study, a comprehensive framework is introduced to obtain the response in frequency and time domains under arbitrary loads, considering warping effects. First, a Laplace Transform approach provides the dynamic Green's functions of the beam, which can be used to obtain the frequency response to arbitrary loads by applying simple integration rules of the theory of generalized functions. Next, on deriving suitable orthogonality conditions for the undamped coupled bending-torsion modes, modal impulse and modal frequency response functions are obtained for any load. The solutions are derived under the assumption of proportional damping; they are exact and easy to implement. Finally, the proposed framework is formulated for beams with in-span transversal stiffeners, external supports and is generalized to non-proportional damping including the presence of in-span external dampers. • Triply-coupled bending-torsional dynamics of beams with asymmetric cross section is addressed. • An original framework is introduced for bare beams and generalized to beams with attachments. • Exact dynamic Green's functions and frequency response functions are obtained by a novel approach based on Laplace Transform. • Appropriate orthogonality conditions are derived and used to build the exact modal responses. • Solutions are derived in presence of proportional and non-proportional damping. [ABSTRACT FROM AUTHOR]

• A floating absorber is devised for floating wind turbine pitch mitigation. • The floating absorber does not cause dead load on the wind turbine. • The mass of the floating absorber may be chosen suitably large. • The floating absorber is tuned by a fixed point theory adapted to MDOF absorbers. • Pitch reductions of almost 30% are achieved for some load conditions in time domain. This paper proposes the innovative concept of floating absorber for motion mitigation in floating wind turbines on spar supports. The floating absorber consists in a spar floater coupled with the floating wind turbine by an elastic spring and a viscous damper in parallel. It is conceived to act as a resonant mass tuned to the pitch frequency of the floating wind turbine and, for this purpose, its parameters are calibrated based on the well-established fixed point tuning procedure typically applied for tuned mass dampers. For validation, extensive time-domain numerical simulations are performed on a multi-degree-of-freedom computational model of the coupled system, considering thirty-six different configurations of the floating absorber and fifteen different combinations of wind-wave conditions. The results demonstrate a considerable effectiveness of the floating absorber in reducing the pitch motion of the floating wind turbine. A main advantage over conventional tuned mass devices is that the absorber is not housed in the nacelle of the wind turbine but floats close to the floating wind turbine. This not only ensures reduced costs of installation and maintenance of the floating absorber but allows, also, to increase its mass without causing extra weight on the floating wind turbine, exploiting hydrodynamic added mass as well, with consequent benefits in terms of motion mitigation in the floating wind turbine. Another relevant result is that, for a given mass of the floating absorber and a given attachment point of the parallel spring-dashpot, the performances of the floating absorber do not vary significantly with its geometry. This is important to facilitate design and manufacturing of the floating absorber, confirming the robustness of the proposed concept and its great potential for motion mitigation in floating wind turbines. [ABSTRACT FROM AUTHOR]