438 research outputs found
Interventional Ultrasound in Dermatology: A Pictorial Overview Focusing on Cutaneous Melanoma Patients
Cutaneous melanoma incidence is increasing worldwide, representing an aggressive tumor when evolving to the metastatic phase. High-resolution ultrasound (US) is playing a growing role in the assessment of newly diagnosed melanoma cases, in the locoregional staging prior to the sentinel lymph-node biopsy procedure, and in the melanoma patient follow-up. Additionally, US may guide a number of percutaneous procedures in the melanoma patients, encompassing diagnostic and therapeutic modalities. These include fine needle cytology, core biopsy, placement of presurgical guidewires, aspiration of lymphoceles and seromas, and electrochemotherapy
Application of an additive manufactured hybrid metal/composite shock absorber panel to a military seat ejection system
In this work, a preliminary numerical assessment on the application of an additive manufactured hybrid metal/composite shock absorber panels to a military seat ejection system, has been carried out. The innovative character of the shock absorber concept investigated is that the absorbing system has a thickness of only 6 mm and is composed of a pyramidâshaped lattice core that, due to its small size, can only be achieved by additive manufacturing. The mechanical behaviour of these shock absorber panels has been examined by measuring their ability to absorb and dissipate the energy generated during the ejection phase into plastic deformations, thus reducing the loads acting on pilots. In this paper the effectiveness of a system composed of five hybrid shock absorbers, with very thin thickness in order to be easily integrated between the seat and the aircraft floor, has been numerically studied by assessing their ability to absorb the energy generated during the primary ejection phase. To accomplish this, a numerical simulation of the explosion has been performed and the energy absorbed by the shockâabsorbing mechanism has been assessed. The performed analysis demonstrated that the panels can absorb more than 60% of the energy generated during the explosion event while increasing the total mass of the pilotâseat system by just 0.8%
The Challenges of Promoting Social Inclusion through Sport: The Experience of a Sport- Based Initiative in Italy
Social inclusion is broadly recognized as a priority to accomplish at an international level. While the influence of sport toward this social mission has been largely debated, literature lacks contributions capturing the challenges of sport when promoting social inclusion. Based in case study methodology, the investigation explores the impact of a multi-stakeholder sport initiative developing social inclusion for socially vulnerable youth and the related challenges of the intervention through in- depth interviews with diverse program stakeholders. The main findings indicated the emergence of four challenges: limited transferability of program outcomes for youth in living conditions of severe vulnerability; drop-out of youth in living conditions of severe vulnerability; limited sustainability of program social workers; lack of sports club management skills. The work highlights some limits of sport-based programs for social inclusion and discusses some implications for practice to maximize the societal impact of such interventions
The impact of COVID-19 on radiological findings in patients accessing the emergency department: a multicentric study
The aim of this multicentric study is to illustrate how the COVID-19 pandemic lockdown affected the workload and outcomes of radiological examinations in emergency radiology
Changes and Challenges in Human Resources Management: An Analysis of Human Resources Roles in a Bank Context (after COVID-19)
Background: In the coming years, HR in the banking industry will need to play a leading role to develop human capital management, based on people care, evaluation, development, and training. To properly face this change in one of the biggest Italian banks we wanted to contribute to understanding the actual HR areas of change and examine how HR roles are dealing with âbeing on the frontlineâ of an unparalleled organisational evolution. Methods: Six focus-group sessions with up to 10 participants per session. Results: The crucial issue that emerged is a profound rupture and crisis that showed the (already existing) fragilities of the HR role interpretation: develop a new synergic relationship with the top management; define a stronger and wider organisational mandate; establish structured moments of discussion between professionals. Conclusion: HR roles in the banking context, especially after the pandemic, entail a high emotional burden related to role assumption. Specifically, our research highlighted the need to discuss the evolution of the HR role with top management, the need for synergies and a definition of the organisational mandate that allows wider participation in terms of decision-making and planning, and finally the need for supervision of HR roles
Early detection of pleuro-pulmonary tuberculosis by bedside lung ultrasound: A case report and review of literature
We present a case in which lung ultrasound (LUS) was relevant to reach an early diagnosis of lung tuberculosis and to manage the patient in the right setting. Moreover, ultrasound allowed to detect and treat massive pleural effusion through an ultrasound-guided thoracentesis
On smoothness-asymmetric null infinities
We discuss the existence of asymptotically Euclidean initial data sets to the
vacuum Einstein field equations which would give rise (modulo an existence
result for the evolution equations near spatial infinity) to developments with
a past and a future null infinity of different smoothness. For simplicity, the
analysis is restricted to the class of conformally flat, axially symmetric
initial data sets. It is shown how the free parameters in the second
fundamental form of the data can be used to satisfy certain obstructions to the
smoothness of null infinity. The resulting initial data sets could be
interpreted as those of some sort of (non-linearly) distorted Schwarzschild
black hole. Its developments would be so that they admit a peeling future null
infinity, but at the same time have a polyhomogeneous (non-peeling) past null
infinity.Comment: 13 pages, 1 figur
On geometric problems related to Brown-York and Liu-Yau quasilocal mass
We discuss some geometric problems related to the definitions of quasilocal
mass proposed by Brown-York \cite{BYmass1} \cite{BYmass2} and Liu-Yau
\cite{LY1} \cite{LY2}. Our discussion consists of three parts. In the first
part, we propose a new variational problem on compact manifolds with boundary,
which is motivated by the study of Brown-York mass. We prove that critical
points of this variation problem are exactly static metrics. In the second
part, we derive a derivative formula for the Brown-York mass of a smooth family
of closed 2 dimensional surfaces evolving in an ambient three dimensional
manifold. As an interesting by-product, we are able to write the ADM mass
\cite{ADM61} of an asymptotically flat 3-manifold as the sum of the Brown-York
mass of a coordinate sphere and an integral of the scalar curvature plus
a geometrically constructed function in the asymptotic region outside
. In the third part, we prove that for any closed, spacelike, 2-surface
in the Minkowski space for which the Liu-Yau mass is
defined, if bounds a compact spacelike hypersurface in ,
then the Liu-Yau mass of is strictly positive unless lies on
a hyperplane. We also show that the examples given by \'{O} Murchadha, Szabados
and Tod \cite{MST} are special cases of this result.Comment: 28 page
On the Shear Instability in Relativistic Neutron Stars
We present new results on instabilities in rapidly and differentially
rotating neutron stars. We model the stars in full general relativity and
describe the stellar matter adopting a cold realistic equation of state based
on the unified SLy prescription. We provide evidence that rapidly and
differentially rotating stars that are below the expected threshold for the
dynamical bar-mode instability, beta_c = T/|W| ~ 0.25, do nevertheless develop
a shear instability on a dynamical timescale and for a wide range of values of
beta. This class of instability, which has so far been found only for small
values of beta and with very small growth rates, is therefore more generic than
previously found and potentially more effective in producing strong sources of
gravitational waves. Overall, our findings support the phenomenological
predictions made by Watts, Andersson and Jones on the nature of the low-T/|W|.Comment: 20 pages; accepted to the Classical and Quantum Gravity special issue
for MICRA200
Some triviality results for quasi-Einstein manifolds and Einstein warped products
In this paper we prove a number of triviality results for Einstein warped
products and quasi-Einstein manifolds using different techniques and under
assumptions of various nature. In particular we obtain and exploit gradient
estimates for solutions of weighted Poisson-type equations and adaptations to
the weighted setting of some Liouville-type theorems.Comment: 15 pages, fixed minor mistakes in Section
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