Diffusion in a crowded environment

We analyze a pair of diffusion equations which are derived in the infinite system--size limit from a microscopic, individual--based, stochastic model. Deviations from the conventional Fickian picture are found which ultimately relate to the depletion of resources on which the particles rely. The macroscopic equations are studied both analytically and numerically, and are shown to yield anomalous diffusion which does not follow a power law with time, as is frequently assumed when fitting data for such phenomena. These anomalies are here understood within a consistent dynamical picture which applies to a wide range of physical and biological systems, underlining the need for clearly defined mechanisms which are systematically analyzed to give definite predictions.Comment: 4 pages, 3 figures, minor change

The healthcare organization in COVID-19 age: An evaluation framework for the performance of a telemonitoring model

Telemedicine services (TS) are not only supportive for healthcare professionals, but managers also see them as essential for the provision of an efficient, effective, and sustainable healthcare service. Several systems make TS available in different ways and contexts. However, no commonly accepted framework meets the need to draw conclusions about which TS can efficiently be measured. For this purpose, a framework is proposed in order to define a dynamic method of performance evaluation that can be used to improve the sustainable management of a telemonitoring model for COVID-19 patients. A case study analysis based on the experience of three telemedicine networks in different locations providing telemonitoring services (northern, central, and southern Italy) was performed. A total of four phases (1. Identification of the target population; 2. Identification of health needs; 3. Definition of the operational plan; and 4. Monitoring of the service by indicators), and seven indicators have been identified. Despite the differences raised in the Italian contexts, applying a performance evaluation framework could help the managerial sector to understand if the service is working as intended and what effects the service is producing on the healthcare organization. Considering the long-term field experience, this framework is an easy-to-use tool that will allow healthcare organizations to evaluate the performance of their telemonitoring model, and improve it according to new needs. Providing a healthcare service in an efficient context is fundamental for the sustainability of the health system as a whole

Indicators and criteria for efficiency and quality in public hospitals: A performance evaluation model

In many countries, the public sector is currently characterised by the need to improve its performance. The implementation of performance measurement systems is essential to generate better results, especially in the public health sector. In healthcare practice, clinical indicators are part of a performance measurement system, and are a way of assessing the quality of care by investigating the frequency of specific results. Through a clinical audit process, this study aims to define the criteria and key performance indicators for minimally invasive endovascular surgical treatment. This type of treatment is chosen because aortic pathologies are an important European issue in cardiovascular surgery. A model of criteria and indicators used in a large public Italian hospital was constructed in order to assess the level of performance achieved with this service

Matrix algebras in quasi-newtonian algorithms for optimal learning in multi-layer perceptrons

In this work the authors implement in a Multi-Layer Perceptron (MLP) environment a new class of quasi-newtonian (QN) methods. The algorithms proposed in the present paper use in the iterative scheme of a generalized BFGS-method a family of matrix algebras, recently introduced for displacement decompositions and for optimal preconditioning. This novel approach allows to construct methods having an O(n log_2 n) complexity. Numerical experiences compared with the performances of the best QN-algorithms known in the literature confirm the effectiveness of these new optimization techniques

Low complexity secant quasi-Newton minimization algorithms for nonconvex functions

In this work some interesting relations between results on basic optimization and algorithms for nonconvex functions (such as BFGS and secant methods) are pointed out. In particular, some innovative tools for improving our recent secant BFGS-type and LQN algorithms are described in detail

Inside and outside the boardroom: Collaborative practices in the performing arts sector

Collaboration is crucial in the arts sector, where forms of collaborative governance (CG) – the inclusion of private partners in the decision-making process – have been implemented in order to overcome scarcity of resources and to engage with stakeholders. The governance of performing arts organizations today must be based on constant collaboration between public and private entities in order to generate greater value. The purpose of this study is to identify the drivers of CG in performing arts organizations by means of a case study of I Teatri Foundation of Reggio-Emilia, one of the first theatres in Italy to include private partners in governance. The methodology is based on both documentary analysis and interviews. The findings show that CG should be applied at micro and meso levels (inside and outside the boardroom), as both levels contribute to the creation of value for the audience

Intrinsic noise and discrete-time processes

A general formalism is developed to construct a Markov chain model that converges to a one-dimensional map in the infinite population limit. Stochastic fluctuations are therefore internal to the system and not externally specified. For finite populations an approximate Gaussian scheme is devised to describe the stochastic fluctuations in the non-chaotic regime. More generally, the stochastic dynamics can be captured using a stochastic difference equation, derived through an approximation to the Markov chain. The scheme is demonstrated using the logistic map as a case study.Comment: Modified version accepted for publication in Phys. Rev. E Rapid Communications. New figures adde

On the best least squares fit to a matrix and its applications

The best least squares fit L_A to a matrix A in a space L can be useful to improve the rate of convergence of the conjugate gradient method in solving systems Ax=b as well as to define low complexity quasi-Newton algorithms in unconstrained minimization. This is shown in the present paper with new important applications and ideas. Moreover, some theoretical results on the representation and on the computation of L_A are investigated

Inside and outside the boardroom: Collaborative practices in the performing arts sector

Collaboration is crucial in the arts sector, where forms of collaborative governance (CG) – the inclusion of private partners in the decision-making process – have been implemented in order to overcome scarcity of resources and to engage with stakeholders. The governance of performing arts organizations today must be based on constant collaboration between public and private entities in order to generate greater value. The purpose of this study is to identify the drivers of CG in performing arts organizations by means of a case study of I Teatri Foundation of Reggio-Emilia, one of the first theatres in Italy to include private partners in governance. The methodology is based on both documentary analysis and interviews. The findings show that CG should be applied at micro and meso levels (inside and outside the boardroom), as both levels contribute to the creation of value for the audience