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In the public debate played out in the media, the financial crisis in Italy is often depicted through a culturalist frame; the country’s difficulties are traced deterministically to an ethos, supposedly widespread among Italians, of amoral familism and a limited sense of civic engagement. This paper illustrates three issues that exemplify the country’s financial problems, and which are often seen through this type of culturalist lens: i) a lack of discipline in managing public finances; ii) a lack of interest in co-operation caused by the excessive importance given to family ties; iii) a lack of agency from the people involved, symbolised by a reluctance to leave home and to adopt an intense pace of work. Considering the relevant literature and various statistics, we show that a culturalist approach helps to spread a stereotyped and misleading view of these three issues. Instead, we suggest that a more accurate reading of the situation, and more stimulating when it comes to public debate, can be obtained by observing the way individuals adapt to the limitations and opportunities of the context in which they operate.
Prospective studies assessing the association between fibre intake or fibre-rich food consumption and the risk of CVD have often been limited by baseline assessment of diet. Thus far, no study has used yearly repeated measurements of dietary changes during follow-up. Moreover, previous studies included healthy and selected participants who did not represent subjects at high cardiovascular risk. We used yearly repeated measurements of diet to investigate the association between fibre intake and CVD in a Mediterranean cohort of elderly adults at high cardiovascular risk. We followed-up 7216 men (55–80 years) and women (60–80 years) initially free of CVD for up to 7 years in the PREvención con DIeta MEDiterránea study (registered as ISRCTN35739639). A 137-item validated FFQ was repeated yearly to assess diet. The primary end point, confirmed by a blinded ad hoc Event Adjudication Committee, was a composite of cardiovascular death, myocardial infarction and stroke. Time-dependent Cox’s regression models were used to estimate the risk of CVD according to baseline dietary exposures and to their yearly updated changes. We found a significant inverse association for fibre (Pfor trend=0·020) and fruits (Pfor trend=0·024) in age-sex adjusted models, but the statistical significance was lost in fully adjusted models. However, we found a significant inverse association with CVD incidence for the sum of fruit and vegetable consumption. Participants who consumed in total nine or more servings/d of fruits plus vegetables had a hazard ratio 0·60 (95 % CI 0·40, 0·96) of CVD in comparison with those consuming <5 servings/d.
We consider here the effects of inertia on the instability of a flat liquid film under the effects of capillary and intermolecular forces (van der Waals interaction). Firstly, we perform a linear stability analysis within the long-wave approximation, which shows that the inclusion of inertia does not produce new regions of instability other than the one previously known from the usual lubrication case. The wavelength,
, corresponding to the maximum growth,
and the critical (marginal) wavelength do not change. The most affected feature of the instability under an increase of the Laplace number is the noticeable decrease of the growth rates of the unstable modes. In order to put in evidence the effects of the bidimensional aspects of the flow (neglected in the long-wave approximation), we also calculate the dispersion relation of the instability from the linearized version of the complete Navier–Stokes (N–S) equations. Unlike the long-wave approximation, the bidimensional model shows that
can vary significantly with inertia when the aspect ratio of the film is not sufficiently small. We also perform numerical simulations of the nonlinear N–S equations and analyse to which extent the linear predictions can be applied depending on both the amount of inertia involved and the aspect ratio of the film.
Flysch-type, syn-orogenic deposits of Carboniferous age occur in relation to the emplacement of a large allochthonous nappe stack in the Variscan belt of NW Iberia. New U–Pb age populations of detrital zircons obtained using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) are considered together with others from previously dated samples to establish the relationships between sedimentation and thrusting. The age populations of four syn-orogenic formations are compared with those of the pre-orogenic sequence in the Autochthon and Parautochthon, representing the Gondwanan passive margin, and in the Allochthon, formed by peri-Gondwanan and oceanic terranes. In addition, a new structural study has been carried out to understand the relationships between the syn-orogenic deposits and the development of Variscan structures. The aims are to identify the sources of sediments and to establish the relationship between Variscan structural evolution and syn-orogenic sedimentation. Development of a forebulge outwards from the allochthonous front, deduced from the structural study, suggests the existence of depocentres that hosted the syn-orogenic sediments. Together with the trend shown by the more recent zircons in each formation, that are younger towards the external zones, the data suggest that sedimentation occurred in progressively migrating depocentres formed in front of the allochthonous wedge during its emplacement. The zircon age populations point to the Allochthon as the main source of detritus for the syn-orogenic basins, with perhaps a limited participation of the Parautochthon and Autochthon in the younger formations.
Between 2005 and 2007, the presence of Onchocerca flexuosa (Wedl, 1856) was discovered and investigated in 110 red deer (Cervus elaphus) shot in the Riaño Regional Hunting Reserve, in the province of León (north-western Spain). Nodules containing O. flexuosa were located in the dorsal region and flanks of the deer. These were collected and measured, and some adult parasites were extracted from the nodules and identified by morphology and by obtaining mitochondrial 12S rDNA sequences, which were identical to those of previously published sequences for O. flexuosa. Some nodules were prepared for histology, embedded in paraffin, sectioned and stained with haematoxylin–eosin. Histologically, the worms were found in several compartments separated by an infiltrated fibrous tissue. These compartments were inhabited by several females and males, surrounded by a fibrous capsule. A total of 85.45% (95% confidence interval (CI): 78.86–92.04%) of red deer were parasitized, with a mean intensity of 9.53 ± 12.27 nodules/host, ranging between 1 and 74 nodules/deer. Significant differences in prevalence and intensity of infection were found between young and adult red deer, and also between seasons. However, no significant differences between males and females were observed. Five hundred and ninety-seven nodules were measured (15.81 ± 3.94 mm) and classified by sizes into small ( < 10 mm), medium (10–20 mm) and large (>20 mm). No relation was found between the size of the nodules and the time of infection. The high values found in the studied parameters show that northern Spain is an area of high-intensity infection for deer.
We study the stability of a viscous incompressible fluid ring on a partially wetting substrate within the framework of long-wave theory. We discuss the conditions under which a static equilibrium of the ring is possible in the presence of contact angle hysteresis. A linear stability analysis (LSA) of this equilibrium solution is carried out by using a slip model to account for the contact line divergence. The LSA provides specific predictions regarding the evolution of unstable modes. In order to describe the evolution of the ring for longer times, a quasi-static approximation is implemented. This approach assumes a quasi-static evolution and takes into account the concomitant variation of the instantaneous growth rates of the modes responsible for either collapse of the ring into a single central drop or breakup into a number of droplets along the ring periphery. We compare the results of the LSA and the quasi-static model approach with those obtained from nonlinear numerical simulations using a complementary disjoining pressure model. We find remarkably good agreement between the predictions of the two models regarding the expected number of drops forming during the breakup process.
Even though Ecuador is one of the twelve mega-diverse countries in the world, the polychaetes are still poorly known. Twelve polychaete species, namely Hemipodia pustatula (Glyceridae); Microphthalmus arenarius (Hesionidae); Scoletoma zonata (Lumbrineridae); Nereis riisei, Pseudonereis gallapagensis (Nereididae); Armandia salvadoriana, Euzonus mucronata (Opheliidae); Phyllodoce multiseriata (Phyllodocidae); Pisione longispinulata (Pisionidae); Malacoceros indicus, Scolelepis (Scolelepis) acuta (Spionidae) and Opisthosyllis arboricola (Syllidae) are newly reported in the intertidal sandy beaches of Bunche (0°39′01.98″N 80°03′55.01″W) and Cabo San Francisco (0°38′16.35″N 80°03′14.07″W), Esmeraldas Province (Ecuador). Furthermore, an amended diagnosis of Pisione longispinulata is presented.
Few books on the subject of Riemann surfaces cover the relatively modern theory of dessins d'enfants (children's drawings), which was launched by Grothendieck in the 1980s and is now an active field of research. In this 2011 book, the authors begin with an elementary account of the theory of compact Riemann surfaces viewed as algebraic curves and as quotients of the hyperbolic plane by the action of Fuchsian groups of finite type. They then use this knowledge to introduce the reader to the theory of dessins d'enfants and its connection with algebraic curves defined over number fields. A large number of worked examples are provided to aid understanding, so no experience beyond the undergraduate level is required. Readers without any previous knowledge of the field of dessins d'enfants are taken rapidly to the forefront of current research.
Definition 4.1 A dessin d'enfant, or simply a dessin, is a pair (X, D) where X is an oriented compact topological surface, and D ⊂ X is a finite graph such that:
(i) D is connected.
(ii) D is bicoloured, i.e. the vertices have been given either white or black colour and vertices connected by an edge have different colours.
(iii) X \ D is the union of finitely many topological discs, which we call faces of D.
The genus of (X, D) is simply the genus of the topological surface X.
We consider two dessins (X1, D1) and (X2, D2) equivalent when there exists an orientation-preserving homeomorphism from X1 to X2 whose restriction to D1 induces an isomorphism between the coloured graphs D1 and D2.
Remark 4.2 In fact condition (i) is a consequence of condition (iii) as it is fairly obvious that any path in X connecting two given points of D is homotopic to a path supported on the boundary of the faces encountered along the way.
Remark 4.3 Some authors remove condition (ii) with the understanding that to any (single-coloured) graph satisfying conditions (i) and (iii), a dessin is associated by placing a new vertex in the middle of each edge. This process produces only dessins where all the white vertices have degree 2, a restriction that looks rather unnatural from the point of view of bicoloured graphs. These graphs are classically known as maps (see [JS78] and the references given there), and the associated dessins are the ones originally introduced by Grothendieck [Gro97].
The present text is an expanded version of the lecture notes for a course on Riemann surfaces and dessins d'enfants which the authors have taught for several years to students of the masters degree in mathematics at the Universidad Autónoma de Madrid.
Riemann surfaces are an ideal meeting ground for several branches of mathematics. For example, a student taking a course like this will encounter concepts of algebraic topology (fundamental group, theory of covering spaces, monodromy), elements of Riemannian geometry (geodesics, isometries, tessellations), objects belonging to algebra and algebraic geometry (field extensions, algebraic curves, valuations), definitions belonging to arithmetic geometry (fields of moduli and definition of an algebraic variety), some elementary graph theory (dessins d'enfants), tools of (complex) analysis (Weierstrass functions and Poincaré series) and some of the most relevant groups in analytic number theory (principal congruence subgroups).
One of the main features of the theory of Riemann surfaces is that there is a bijective correspondence between isomorphism classes of compact Riemann surfaces and isomorphism classes of complex algebraic curves. Establishing this correspondence requires proving first that a Riemann surface has enough meromorphic functions to separate its points. This can be done by either applying the Riemann–Roch Theorem or using the Uniformization Theorem to construct these functions by means of Poincaré series (Weierstrass functions, in the genus one case). In this book we have chosen the second option, thereby introducing Fuchsian groups, the third member of this trinity of equivalent objects.
The present paper is the first annotated account listing all species of Cirripedia: Thoracica recorded from the Canary Islands (eastern Atlantic Ocean) together with notes on their distribution and ecology. Voucher specimens have been deposited as reference material in the collection of the Instituto Canario de Ciencias Marinas. Seventeen species are listed and seven of them are recorded for the first time for the Canaries: Lepas hilli, Conchoderma virgatum, Xenobalanus globicipitis, Chthamalus sp. (cf. C. proteus), Acasta cyathus, Balanus trigonus and Perforatus perforatus.
The instability of a liquid layer coating the surface of a thin cylindrical wire is studied experimentally and numerically with negligible gravity effects. The initial uniform film is obtained as the residual of a sliding drop, and the thickness measurements are performed with an anamorphic optical system that compresses the vertical scale (allowing to observe several wavelengths) and widens the horizontal one (to follow in detail the evolution of local minima and maxima). Experimental timelines showing the growth and position of the maxima and minima are compared with linear theory and fully nonlinear simulations. A primary mode grows in the early stages of the instability, and its wavelength λ1 is not always in agreement with that corresponding to the maximum growth rate predicted by the linear theory λm. In later stages, a secondary mode appears, whose wavelength is half that of the primary mode. The behaviour of the secondary mode allows us to classify the experimental results into two cases, depending on whether it is linearly stable (case I) or unstable (case II). In case I, the amplitude of the secondary mode remains small compared with that of the primary one, while in case II both amplitudes may become very similar at the end. Thus, the distance between the final drops may be quite different from that seen between initial protuberances. The analysis of the experiments allows us to define a simple criterion based on the comparison between λ1 and λm. Contrary to the predictions of widely used previous quasi-static theories, experiments show that the relation between maximum and minimum of the primary mode is better approximated by a kinematic model based on the assumption that primary maxima increase as fast as the minima decrease. Numerical simulations confirm this hypothesis.