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The purpose of this paper is to compare the fluid dynamic performance of two Aqueous Humor (AH) ocular drainage devices, the SOLX® Gold Micro Shunt (GMS) and the novel Silicon Shunt Device (SSD), implanted by surgeons in human eyes to reduce the IntraOcular Pressure towards physiological values, by draining the AH from the Anterior Chamber to the Suprachoroidal Space, to cure eyes with glaucoma.

The generalized porous medium model is solved to simulate the AH flow through the two ocular drainage devices and the surrounding porous tissues of the eye.

In the GMS, probable stagnation regions have been found, due to the very small AH velocity values inside the device and to the surrounding tissues, creating possible blockage and malfunction of the device. The simple microtubular geometry of the novel SSD allows to have a regular AH flow and to choose shunts with different diameters and/or with the presence of radial holes, based on patient needs, with consequent reduction of post-operative complications.

The present model will be further developed taking into account the insertion of the present drainage devices inside the anterior section of the eye. The present results show the comparative fluid dynamic performance of the two shunts considered, and can be useful for surgeons to choose the adequate shunt, based on the required AH flow rate for a specific patient.

The present numerical approach, employing the generalized porous medium model, represents a useful tool to study the fluid dynamics of ocular drainage devices and to design these shunts, to reduce post-operative complications.

The generalized porous medium model is here applied for the first time to simulate the interaction of ocular drainage devices with the surrounding porous tissues of the eye.

This paper aims to derive a reduced-order model for the heat transfer across the interface between a millimetric thermocapillary liquid bridge from silicone oil and the surrounding ambient gas.

Numerical solutions for the two-fluid model are computed covering a wide parametric space, making a total of 2,800 numerical flow simulations. Based on the computed data, a reduced single-fluid model for the liquid phase is devised, in which the heat transfer between the liquid and the gas is modeled by Newton’s heat transfer law, albeit with a space-dependent Biot function Bi(z), instead of a constant Biot number Bi.

An explicit robust fit of Bi(z) is obtained covering the whole range of parameters considered. The single-fluid model together with the Biot function derived yields very accurate results at much lesser computational cost than the corresponding two-phase fully-coupled simulation required for the two-fluid model.

Using this novel Biot function approach instead of a constant Biot number, the critical Reynolds number can be predicted much more accurately within single-phase linear stability solvers.

The Biot function for thermocapillary liquid bridges is derived from the full multiphase problem by a robust multi-stage fit procedure. The derived Biot function reproduces very well the theoretical boundary layer scalings.

The aim of this paper is to explore the family firms' propensity to undertake R&D investments after going public, showing how it varies due to the ownership structure.

The analysis is based on a sample of 132 French and Italian family and nonfamily IPOs in the period 2013–2018.

The empirical findings show a positive relationship between the quantity of post-IPO shares retained by family owners and R&D investments. Furthermore, the abovementioned relationship is negatively affected by the generational stage and positively by the presence of a lone founder.

Outside investors of family firms may be assured in buying shares of founding family firms after going public because they are stimulated to undertake R&D investments and therefore create overall value in the long term. Furthermore, external managers of lone-founder and first-generation family firms can adopt innovation investments without fear of being replaced as a consequence of a hostile takeover. Lastly, private equity should support later generation family IPOs, providing them with capital and managerial skills in order to generate value for shareholders.

Past studies have mostly shown family firms' reluctance to undertake R&D investments; however, scholars have focused on private or public family firms, ruling out the analysis of family firms' innovation behaviour within the setting of an IPO. To the best of the author's knowledge, this study represents the first empirical attempt to investigate the relationship between family firms and post-IPO innovation investments, when the capital infusion relaxes the financial constraints of family firms.

Since healthcare spending accounts for approximately 6.6 per cent of the gross domestic product, reducing waste in health facilities is necessary to generate significant cost savings. After previous work concerning the application of Lean Six Sigma (LSS) to hip surgery, the purpose of this paper is to use LSS as the correct methodology to analyse a clinical pathway. Fast track surgery was introduced to the Complex Operative Unit of Orthopaedic and Traumatology of the University Hospital “Federico II” to improve quality and further reduce costs associated with prosthetic hip replacement surgery.

The DMAIC (Define, measure, analyse, improve, control) roadmap was used as the typical problem-solving approach of the LSS methodology. A rigorous process of defining, measuring, analysing, improving and controlling business problems can be used to reach fixed goals. The paper was written following the Standards for Quality Improvement Reporting Excellence (SQUIRES Guidelines).

In this work, the authors found that multiple variables could influence the length of hospital stay (LOS) for inpatient treatment, thereby increasing patient management costs due to longer periods of hospitalisation. Therefore, LSS analysis of the implemented corrective actions demonstrated the efficacy and efficiency of the novel protocol. The average LOS was reduced from 10.66 to 7.8 days (−26.8 per cent).

The introduction of fast track surgery was validated through a rigorous LSS analysis, which demonstrated that the new protocol benefitted both patients and the hospital.

This paper aims to uncover the combinations of knowledge sharing mechanisms that organizations in a science and technology park in Brazil use to share managerial and technical knowledge.

This research adopts a qualitative approach that uses a fuzzy set qualitative comparative analysis to analyze data that are gathered from 51 managers of organizations in a science and technology park.

The results show that knowledge sharing happens regardless of the type of knowledge. There are more alternative paths that lead to knowledge sharing than to its absence. Regarding the type of knowledge shared, there are more alternative configurations that lead to managerial knowledge sharing than to technical knowledge sharing. Only the older organizations in the science and technology park abstain from knowledge sharing.

Due to the qualitative nature of the study, no generalization is possible. Additionally, the study’s limitation is that it involves organizations from a single science and technology park.

The results offer managers of organizations in science and technology parks to choose from alternative combinations of mechanisms to either boost their knowledge sharing or to promote knowledge protection.

The paper provides an original contribution by identifying the combinations of mechanisms that organizations in a science and technology park use that leads to the sharing of specific knowledge types. The findings also identify the combination of mechanisms that older organizations use that prevents them from sharing knowledge.

The reduction of costs has a more and more relevant role in the healthcare context, therefore, a large effort is done by health providers to this aim, for example, by reducing the length of hospital stay (LOS) of patients undergoing surgery. Fast track surgery fits perfectly this issue and was applied to patients undergoing knee replacement surgery due to Osteoarthritis, one of the most common diseases of aged population. The paper aims to discuss these issues.

Lean six sigma was applied to analyze the implementation of fast track surgery through the define, measure, analyze, improve, control roadmap, used as a typical problem-solving approach. It is characterized by five operational phases, which make possible the achievement of fixed goals through a rigorous process of defining, measuring, analyzing, improving and controlling business problems.

The corrective action, consisting in the application of fast track surgery, improved both effectiveness and efficiency of the process of care. The average length of hospital stay (LOS) was reduced from 8.34 to 6.68 days (–19.9 percent) and its standard deviation from 2.41 to 1.99 days (–17.1 percent). The statistical significance of this decrease was verified by means of proper tests. Moreover, some variables influencing the LOS were identified.

The follow up and the satisfaction of patients were not analyzed and could be a future development of this study.

Patients will experience a faster recovery while the hospital will benefit from a rise of available beds. The effect is a general improvement of hospital management.

The introduction of fast track surgery for patients undergoing knee replacement surgery made significantly reduce LOS and, consequently, costs’ with a money saving of more than 50,000 euro per year.

Nobody concerned with political economy can neglect the history of economic doctrines. Structural changes in the economy and society influence economic thinking and, conversely, innovative thought structures and attitudes have almost always forced economic institutions and modes of behaviour to adjust. We learn from the history of economic doctrines how a particular theory emerged and whether, and in which environment, it could take root. We can see how a school evolves out of a common methodological perception and similar techniques of analysis, and how it has to establish itself. The interaction between unresolved problems on the one hand, and the search for better solutions or explanations on the other, leads to a change in paradigma and to the formation of new lines of reasoning. As long as the real world is subject to progress and change scientific search for explanation must out of necessity continue.

The librarian and researcher have to be able to uncover specific articles in their areas of interest. This Bibliography is designed to help. Volume IV, like Volume III, contains features to help the reader to retrieve relevant literature from MCB University Press' considerable output. Each entry within has been indexed according to author(s) and the Fifth Edition of the SCIMP/SCAMP Thesaurus. The latter thus provides a full subject index to facilitate rapid retrieval. Each article or book is assigned its own unique number and this is used in both the subject and author index. This Volume indexes 29 journals indicating the depth, coverage and expansion of MCB's portfolio.

The purpose of this study concerns numerical studies and experimental validation of the mechanical behavior of hybrid specimens. These kinds of composite specimens are made up of thin carbon and glass substrates on which some Macro Fiber Composite^® (MFC) piezoelectric patches are glued. A proper design and manufacturing of the hybrid specimens as well as testing activities have been performed. The research activity has been carried out under the FutureWings project, funded by the European Commission within the 7th Framework.

The paper describes the basic assumptions made to define specimen geometries and to carry out experimental tests. Finite element (FE) results and experimental data (laser technique measurements) have been compared: it shows very good agreement for the displacements’ distribution along the specimens.

Within the objectives of the project, the study of passive and active deformation characteristics of the hybrid composite material has provided reference technical data and has allowed for the correct adaptation of the FE models. More in particular, using the hybrid specimens, both the bending deformations and the torsion deformations have been studied.

The deformation capability of the hybrid specimens will be used in the development of prototypical three-dimensional structures, that, through the electrical control of the MFC patches, will be able to change the curvature of their cross section or will be able to change the angle of torsion along their longitudinal axis.

The design of nonstandard specimens and the tests executed represent a novelty in the field of structures using piezoelectric actuators. The numerical and experimental data of the present research constitute a small step forward in the field of smart materials technology.

This study aims to analyze the territory as a distinctive factor through which the concept and practice of “Made in Italy” operates. Specifically, the study considers the role of local and sub-national entrepreneurial collaborations that preserve and enhance factors such as history, style and talent as the essence of Italian “quality” and as the pillar of Italian territorial capitalism.

The research examines this Italian phenomenon by investigating small and medium enterprises (SMEs) that successfully compete abroad (and also in the domestic market) with a “glocal” approach, adopting the entrepreneurial formula of industrial districts.

The results indicate that international expansion is becoming increasingly more complex (as is every growth/development strategy) but that “glocalism” could represent a potential driver for the success of internationalization strategies. Specifically, for SMEs operating in industrial districts, territorial capitalism could emerge as a unique competitive factor, because it is a component of local structural capital and global reputational capital, as in the case of “Made in Italy.”

In an increasingly globalized market environment, many companies look to foreign markets to maintain and expand competitive advantage and business performance. Once the companies embark on this endeavor, organizations are involved in governing and managing these networks of finance, production and communication and the distribution-related relationships that constitute globalization. The push to engage in international development is currently imperative for SMEs, which need to extend their business engagement beyond conventional local markets and identify and exploit their distinctive competitive advantage to be able to succeed. One possible way of achieving this is the close interaction with the local territories in which these enterprises reside.