Portfolio Structuring Model for Urban Infrastructure Investments

The objective of this work is to propose a new methodology based on the concept of portfolio structuring for urban infrastructure investment. We argue that city investments need to be treated as an integrated and interdependent entity and from this perspective, the portfolio methodology is proposed in order to assess the non-financial impacts of infrastructure projects and then combine them in a portfolio of investments from a financial perspective. The methodology is applied for a set of project under the EIB JESSICA Initiative. The methodology shows that not only is it possible to develop a practical decision support system to assist stakeholders in assessing the performance of individual urban infrastructure projects, but also how it is possible to combine projects into a portfolio. The method exceeds the simple analysis of returns of individual investment schemes and capitalizes on effective and integrated management of projects/investment. And this is the key to devising a focused response which will enable therefore cities to be globally competitive, via innovative financial and business models

Soliton Dynamics in Linearly Coupled Discrete Nonlinear Schr\"odinger Equations

We study soliton dynamics in a system of two linearly coupled discrete nonlinear Schr\"odinger equations, which describe the dynamics of a two-component Bose gas, coupled by an electromagnetic field, and confined in a strong optical lattice. When the nonlinear coupling strengths are equal, we use a unitary transformation to remove the linear coupling terms, and show that the existing soliton solutions oscillate from one species to the other. When the nonlinear coupling strengths are different, the soliton dynamics is numerically investigated and the findings are compared to the results of an effective two-mode model. The case of two linearly coupled Ablowitz-Ladik equations is also investigated.Comment: to be published in Mathematics and Computers in Simulation, proceedings of the fifth IMACS International Conference on Nonlinear Evolution Equations and Wave Phenomena: Computation and Theory (Athens, Georgia - April 2007

Pattern Forming Dynamical Instabilities of Bose-Einstein Condensates: A Short Review

In this short topical review, we revisit a number of works on the pattern-forming dynamical instabilities of Bose-Einstein condensates in one- and two-dimensional settings. In particular, we illustrate the trapping conditions that allow the reduction of the three-dimensional, mean field description of the condensates (through the Gross-Pitaevskii equation) to such lower dimensional settings, as well as to lattice settings. We then go on to study the modulational instability in one dimension and the snaking/transverse instability in two dimensions as typical examples of long-wavelength perturbations that can destabilize the condensates and lead to the formation of patterns of coherent structures in them. Trains of solitons in one-dimension and vortex arrays in two-dimensions are prototypical examples of the resulting nonlinear waveforms, upon which we briefly touch at the end of this review.Comment: 28 pages, 9 figures, publishe

45,X/46,XY Mosaicism Presenting With Isolated Unilateral Cryptorchidism and a Normal Blood Karyotype

Context: 45,X/46,XY mosaicism is a disorder of sex development leading to abnormal gonadal development and to unpredictable genital phenotype, growth, and pubertal development. / Case Description: A 2-year-old male presented with a right impalpable testis. Blood karyotype was 46,XY. A laparoscopy performed for right orchidopexy revealed a right streak gonad with Mullerian structures, whereas on the left side, a normal descended testis was present. The karyotype of the removed gonad was 45,X/46,XY. The child grew along the second centile, within the midparental height (MPH) range, until the time of puberty, when linear growth worsened due to a lack of a pubertal growth spurt, and growth hormone (GH) therapy was initiated. He developed spontaneous puberty (13 years of age) and showed normal pubertal progression. However, from the age of 15 years, he had low normal testosterone, raised follicle-stimulating hormone, and reduction of inhibin B, possibly suggestive of declining testicular function. His final height was −2.24 standard deviation score (SDS) (−2.4 SDS at GH start; MPH −1.6 SDS). / Conclusions: Our case describes a mild male phenotype associated with 45,X/46,XY mosaicism characterized by unilateral cryptorchidism, spontaneous onset of puberty, and normal blood karyotype. The case illustrates the difficulties inherent in making a diagnosis of 45,X/46,XY mosaicism when there is no genital ambiguity and makes the point that growth and testicular impairment may occur, mostly manifesting during adolescence. An early diagnosis is crucial to initiate careful monitoring for growth and pubertal disorders, increased tumor risk, and fertility issues commonly seen in these children

Addison's disease presenting with perimyocarditis

BACKGROUND: Polyglandular autoimmune syndrome (PGA) and eosinophilic granulomatosis with polyangiitis (EGPA) do not seem to represent a coincidental association. CASE PRESENTATION: A case of a 15-year-old boy is reported who presented with severe systemic inflammation, perimyocarditis and cardiogenic shock, in whom EGPA was initially suspected and later diagnosed with autoimmune adrenalitis with PGA. CONCLUSIONS: The severity of the systemic inflammation and perimyocarditis suggests a more widespread autoimmune-mediated process. Autoimmune adrenal insufficiency should be considered in all cases of pericarditis and perimyocarditis, especially when the severity of clinical manifestations exceeds the expected for the severity of the cardiac findings, as timely identification and prompt treatment may be life-saving

The role of mobility in the dynamics of the COVID-19 epidemic in Andalusia

Metapopulation models have been a popular tool for the study of epidemic spread over a network of highly populated nodes (cities, provinces, countries) and have been extensively used in the context of the ongoing COVID-19 pandemic. In the present work, we revisit such a model, bearing a particular case example in mind, namely that of the region of Andalusia in Spain during the period of the summer-fall of 2020 (i.e., between the first and second pandemic waves). Our aim is to consider the possibility of incorporation of mobility across the province nodes focusing on mobile-phone time dependent data, but also discussing the comparison for our case example with a gravity model, as well as with the dynamics in the absence of mobility. Our main finding is that mobility is key towards a quantitative understanding of the emergence of the second wave of the pandemic and that the most accurate way to capture it involves dynamic (rather than static) inclusion of time-dependent mobility matrices based on cell-phone data. Alternatives bearing no mobility are unable to capture the trends revealed by the data in the context of the metapopulation model considered herein

The ‘Wickedness’ of Governing Land Subsidence: Policy Perspectives From Urban Southeast Asia

Drawing on Jakarta, Metro Manila and Singapore as case studies, we explore the paradox of slow political action in addressing subsiding land, particularly along high-density urban coastlines with empirical insights from coastal geography, geodesy analysis, geology, and urban planning. In framing land subsidence as a classic ‘wicked’ policy problem, and also as a hybrid geological and anthropogenic phenomenon that is unevenly experienced across urban contexts, the paper uses a three-step analysis. First, satellite-derived InSAR maps are integrated with Sentinel-1A data in order to reveal the socio-temporal variability of subsidence rates which in turn pose challenges in uniformly applying regulatory action. Second, a multi-sectoral mapping of diverse policies and practices spanning urban water supply, groundwater extraction, land use zoning, building codes, tenurial security, and land reclamation reveal the extent to which the broader coastal governance landscape remains fragmented and incongruous, particularly in arresting a multi-dimensional phenomenon such as subsidence. Finally, in reference to distinct coastal identities of each city–the ‘Sinking Capital’ (Jakarta), ‘Fortress Singapore’, and the ‘Disaster Capital’ (Manila) the paper illustrates how land subsidence is portrayed across the three metropolises in markedly similar ways: as a reversible, quasi-natural, and/or a highly individualized problem

Solitary Waves Under the Competition of Linear and Nonlinear Periodic Potentials

In this paper, we study the competition of linear and nonlinear lattices and its effects on the stability and dynamics of bright solitary waves. We consider both lattices in a perturbative framework, whereby the technique of Hamiltonian perturbation theory can be used to obtain information about the existence of solutions, and the same approach, as well as eigenvalue count considerations, can be used to obtained detailed conditions about their linear stability. We find that the analytical results are in very good agreement with our numerical findings and can also be used to predict features of the dynamical evolution of such solutions.Comment: 13 pages, 4 figure