High-resolution numerical modelling of flow-vegetation interactions

In this paper, we present and apply a new three-dimensional model for the prediction of canopy-flow and turbulence dynamics in open-channel flow. The approach uses a dynamic immersed boundary technique that is coupled in a sequentially staggered manner to a large eddy simulation. Two different biomechanical models are developed depending on whether the vegetation is dominated by bending or tensile forces. For bending plants, a model structured on the Euler-Bernoulli beam equation has been developed, whilst for tensile plants, an N-pendula model has been developed. Validation against flume data shows good agreement and demonstrates that for a given stem density, the models are able to simulate the extraction of energy from the mean flow at the stem-scale which leads to the drag discontinuity and associated mixing layer.

Services de migration et évolution de la population étrangère dans les cantons suisses 2002-2008 = Migrationsämter und Entwicklung der ausländischen Bevölkerung in den Kantonen 2002-2008

Cette étude montre que les cantons sont confrontés à une augmentation importante de la population étrangère résidante mais aussi du nombre de frontaliers et ceci surtout depuis 2004. La plupart des services cantonaux de migrations sont sous pressions malgré la simplification des formalités pour les ressortissants de l'UE. L'originalité de cette recherche tient au fait qu'elle aborde, pour la première fois, le thème de la population étrangère sous l'angle des activités administratives générées au niveau des cantons. Il s'agit également de la première évaluation présentant dans le détail l'étendue et la multiplication des tâches dévolues à l'Etat du fait de cette immigration depuis l'entrée en vigueur le premier juin 2002 de l'Accord sur la libre circulation des personnes avec l'UE (ACLP). Diese Studie zeigt, dass die Kantone mit einer starken Zunahme der ausländischen Wohnbevölkerung sowie der Zahl Grenzgänger konfrontiert sind. Vor allem seit 2004 sind die Migrationsämter der Kantone, trotz einer Vereinfachung der Formalitäten für EU Angehörige, unter Druck geraten. Die Besonderheit dieser Studie ist, dass sie zum ersten Mal das Thema der ausländischen Bevölkerung aus dem Blickwinkel der administrativen Tätigkeiten der Kantone betrachtet. Es handelt sich auch um die erste Studie, die im Detail die Mehrbelastung durch neue Aufgaben analysiert, welche der Staat auf Grund der Migration seit Inkrafttreten des Personenfreizügigkeits-abkommens (FZA) im Juni 2002 zu leisten leistet hat.

Modified differentials and basic cohomology for Riemannian foliations

We define a new version of the exterior derivative on the basic forms of a Riemannian foliation to obtain a new form of basic cohomology that satisfies Poincaré duality in the transversally orientable case. We use this twisted basic cohomology to show relationships between curvature, tautness, and vanishing of the basic Euler characteristic and basic signature.

Index theory for basic Dirac operators on Riemannian foliations

In this paper we prove a formula for the analytic index of a basic Dirac-type operator on a Riemannian foliation, solving a problem that has been open for many years. We also consider more general indices given by twisting the basic Dirac operator by a representation of the orthogonal group. The formula is a sum of integrals over blowups of the strata of the foliation and also involves eta invariants of associated elliptic operators. As a special case, a Gauss-Bonnet formula for the basic Euler characteristic is obtained using two independent proofs.

Studies on populations of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera: Psychodidae: Phlebotominae) in Brazil

Studies were performed on five Brazilian populations of Lutzomyia longipalpis: Salvaterra (PA), São José do Ribamar (MA), Canindé (CE), Natal (RN) and Gruta da Lapinha, Lagoa Santa (MG). No morphological differences were observed that could distinguish between these populations. Homogeneity tests showed that the allopatric populations display a certain heterogeneity and that the sympatric populations, with different patterns of spots, are homogeneous. The Student-Newman-Keuls test, represented by Euler-Venn diagrams, showed a disjunction between the populations from the north/northeast and the one from Gruta da Lapinha. Genetic distances between the four populations (excluding the Canindé population) were within the range of intrapopulational differences. The Gruta da Lapinha population displayed a heterozygotic deficiency that could be a consequence of high levels of inbreeding due to cryptic habits of living in a small cave. These results do not favor the hypothesis of a L. longipalpis species complex in Brazil, and the species should be considered high polymorphic.

Concurrent cutaneous, visceral and ocular leishmaniasis caused by Leishmania (Viannia) braziliensis in a kidney transplant patient

Although cases of leishmaniasis co-infection have been described in acquired immunodeficiency syndrome patients as well as those who have undergone organ transplants, to our knowledge, the present report is the first documented case of simultaneous cutaneous, visceral and ocular leishmaniasis due to Leishmania (Viannia) braziliensis in a transplant patient. The patient had been using immunosuppressive drugs since receiving a transplanted kidney. The first clinical signs of leishmaniasis included fever, thoracic pain, hepatosplenomegaly, leucopenia and anemia. The cutaneous disease was revealed by the presence of amastigotes in the skin biopsy. After three months, the patient presented fever with conjunctive hyperemia, intense ocular pain and low visual acuity. Parasites isolated from iliac crest, aqueous humor and vitreous body were examined using a range of molecular techniques. The same strain of L. (V.) braziliensis was responsible for the different clinical manifestations. The immunosuppressive drugs probably contributed to the dissemination of Leishmania.

Majorz oder Proporz : Die Auswirkungen des Wahlverfahrens auf die politische Partizipation und das politische Interessein bernischen Gemeinden

Welche Auswirkungen hat das Wahlverfahren auf die politische Partizipation? Unbestritten in der einschlägigen Literatur ist, dass zwischen Wahlverfahren und Wahlbeteiligung ein Zusammenhang besteht, geteilt sind jedoch die Meinungen, ob Proporz- oder Majorzverfahren zu einer höheren Beteiligung führen. Da länderübergreifende Studien diese Frage bis anhin nicht befriedigend zu beantworten vermochten, soll in diesem Aufsatz von der kommunaler Ebene ausgegangen werden. Ganz besonders geeignet dafür sind die rund 400 Gemeinden im Kanton Bern, die zu rund 40 Prozent ihre Exekutiven nach dem Proporzverfahren bestellen. Der grosse Vorteil einer solchen Untersuchungsanlage gegenüber Ländervergleichen ist, dass die kommunalen Systeme hinsichtlich vieler Variablen ein homogeneres Gebiet darstellen, so dass der Effekt des Wahlverfahren besser isoliert werden kann. Die Analysen führen zum Schluss, dass das Proporzverfahren in kleineren Gemeinden zu einer grösseren Wahlbeteiligung führen kann. Verantwortlich dafür ist die grössere Anzahl Parteien in Proporzgemeinden und damit verbunden, eine grössere Zahl an Kandidierenden. Das Proporzwahlverfahren fördert aber nicht grundsätzlich die politische Partizipation in einer Gemeinde.

Support for Seasonal Influenza Vaccination Requirements among US Healthcare Personnel.

Objective. To measure support for seasonal influenza vaccination requirements among US healthcare personnel (HCP) and its associations with attitudes regarding influenza and influenza vaccination and self-reported coverage by existing vaccination requirements. Design. Between June 1 and June 30, 2010, we surveyed a sample of US HCP ([Formula: see text]) recruited using an existing probability-based online research panel of participants representing the US general population as a sampling frame. Setting. General community. Participants. Eligible HCP who (1) reported having worked as medical doctors, health technologists, healthcare support staff, or other health practitioners or who (2) reported having worked in hospitals, ambulatory care facilities, long-term care facilities, or other health-related settings. Methods. We analyzed support for seasonal influenza vaccination requirements for HCP using proportion estimation and multivariable probit models. Results. A total of 57.4% (95% confidence interval, 53.3%-61.5%) of US HCP agreed that HCP should be required to be vaccinated for seasonal influenza. Support for mandatory vaccination was statistically significantly higher among HCP who were subject to employer-based influenza vaccination requirements, who considered influenza to be a serious disease, and who agreed that influenza vaccine was safe and effective. Conclusions. A majority of HCP support influenza vaccination requirements. Moreover, providing HCP with information about the safety of influenza vaccination and communicating that immunization of HCP is a patient safety issue may be important for generating staff support for influenza vaccination requirements.

Orthotropic active strain models for the numerical simulation of cardiac biomechanics

An active strain formulation for orthotropic constitutive laws arising in cardiac mechanics modeling is introduced and studied. The passive mechanical properties of the tissue are described by the Holzapfel-Ogden relation. In the active strain formulation, the Euler-Lagrange equations for minimizing the total energy are written in terms of active and passive deformation factors, where the active part is assumed to depend, at the cell level, on the electrodynamics and on the specific orientation of the cardiac cells. The well-posedness of the linear system derived from a generic Newton iteration of the original problem is analyzed and different mechanical activation functions are considered. In addition, the active strain formulation is compared with the classical active stress formulation from both numerical and modeling perspectives. Taylor-Hood and MINI finite elements are employed to discretize the mechanical problem. The results of several numerical experiments show that the proposed formulation is mathematically consistent and is able to represent the main key features of the phenomenon, while allowing savings in computational costs.

Methodology for studying the numerical speed of sound in finite differences schemes

The space and time discretization inherent to all FDTD schemesintroduce non-physical dispersion errors, i.e. deviations ofthe speed of sound from the theoretical value predicted bythe governing Euler differential equations. A generalmethodologyfor computing this dispersion error via straightforwardnumerical simulations of the FDTD schemes is presented.The method is shown to provide remarkable accuraciesof the order of 1/1000 in a wide variety of twodimensionalfinite difference schemes.

International variation in management of screen-detected ductal carcinoma in situ of the breast.

BACKGROUND: Ductal carcinoma in situ (DCIS) incidence has grown with the implementation of screening and its detection varies across International Cancer Screening Network (ICSN) countries. The aim of this survey is to describe the management of screen-detected DCIS in ICSN countries and to evaluate the potential for treatment related morbidity. METHODS: We sought screen-detected DCIS data from the ICSN countries identified during 2004-2008. We adopted standardised data collection forms and analysis and explored DCIS diagnosis and treatment processes ranging from pre-operative diagnosis to type of surgery and radiotherapy. RESULTS: Twelve countries contributed data from a total of 15 screening programmes, all from Europe except the United States of America and Japan. Among women aged 50-69years, 7,176,050 screening tests and 5324 screen-detected DCIS were reported. From 21% to 93% of DCIS had a pre-operative diagnosis (PO); 67-90% of DCIS received breast conservation surgery (BCS), and in 41-100% of the cases this was followed by radiotherapy; 6.4-59% received sentinel lymph node biopsy (SLNB) only and 0.8-49% axillary dissection (ALND) with 0.6% (range by programmes 0-8.1%) being node positive. Among BCS patients 35% received SLNB only and 4.8% received ALND. Starting in 2006, PO and SLNB use increased while ALND remained stable. SLNB and ALND were associated with larger size and higher grade DCIS lesions. CONCLUSIONS: Variation in DCIS management among screened women is wide and includes lymph node surgery beyond what is currently recommended. This indicates the presence of varying levels of overtreatment and the potential for its reduction.

Policy and the Evolution of the US Economy: 1948-2002

This paper investigates the relationship between monetary policy and the changes experienced by the US economy using a small scale New-Keynesian model. The model is estimated with Bayesian techniques and the stability of policy parameter estimates and of the transmission of policy shocks examined. The model fits well the data and produces forecasts comparable or superior to those of alternative specifications. The parameters of the policy rule, the variance and the transmission of policy shocks have been remarkably stable. The parameters of the Phillips curve and of the Euler equations are varying.

Solving non-linear stochastic models by parameterizing expectations: An application to asset pricing with production

A new algorithm called the parameterized expectations approach(PEA) for solving dynamic stochastic models under rational expectationsis developed and its advantages and disadvantages are discussed. Thisalgorithm can, in principle, approximate the true equilibrium arbitrarilywell. Also, this algorithm works from the Euler equations, so that theequilibrium does not have to be cast in the form of a planner's problem.Monte--Carlo integration and the absence of grids on the state variables,cause the computation costs not to go up exponentially when the numberof state variables or the exogenous shocks in the economy increase. \\As an application we analyze an asset pricing model with endogenousproduction. We analyze its implications for time dependence of volatilityof stock returns and the term structure of interest rates. We argue thatthis model can generate hump--shaped term structures.

Analyse der Hepatitis-C-Situation bei den drogenkonsumierenden Personen in der Schweiz

Die Analyse der Hepatitis-C-Situation bei den drogenkonsumierenden Personen in der Schweiz beruht auf verschiedenen Methoden: Analyse der publizierten und grauen Literatur zu diesem Thema, Sekundäranalyse verfügbarer Daten, Befragung nationaler Fachpersonen, Befragung drogenkonsumierender Personen (DU), Fallstudien in vier Kantonen (Zürich, Waadt, Aargau, Wallis), Internetumfrage bei den Einrichtungen, die DU stationär oder ambulant behandeln, sowie bei den niederschwelligen Einrichtungen zur Risikominderung. In den vergangenen zwei Jahrzehnten erreichte die Zahl der neu gemeldeten Infektionen mit dem Hepatitis-C-Virus (HCV) Ende der 90er-Jahre eine Spitze mit mehr als 2500 Fällen pro Jahr, wobei mehr als 30 % dieser Fälle Personen betrafen, die intravenös Drogen konsumieren (IDU). Die Zahl neu gemeldeter Fälle sank anschliessend bis auf 1500 Fälle im Jahr 2011 und stieg dann wieder auf mehr als 1700 Fälle im Jahr 2013 an. Der Anteil der IDU belief sich auf etwas mehr 20 % (436 Fälle, kein Wiederanstieg der Anzahl neuer Fälle in dieser Bevölkerungsgruppe). Die für die Gesamtbevölkerung der Schweiz geschätzte Prävalenz der HCV-Infektionen bewegt sich je nach Autor zwischen 0,7 % und 1,75 %. Bei Männern, die Sex mit Männern haben (MSM), ist dieser Wert etwas höher (2 %). Bei Staatsangehörigen aus Ländern mit einer höheren Prävalenz (Afrika südlich der Sahara, bestimmte Länder des Nahen Ostens und Südostasiens) ist die Prävalenzrate vermutlich erhöht; es sind jedoch keine Werte bekannt. Auch in Gefängnissen ist die HCV-Prävalenz höher als in der Gesamtbevölkerung, da DU und Staatsangehörige aus Ländern mit höherer Prävalenz stärker vertreten sind (zwischen 5 und 10 %). Es wird davon ausgegangen, dass es bei etwa zwei Drittel der Fälle zu einem chronischen Krankheitsverlauf kommt.

Rate of convergence of a particle method to the solution of the Mc Kean-Vlasov's equation

This paper studies the rate of convergence of an appropriatediscretization scheme of the solution of the Mc Kean-Vlasovequation introduced by Bossy and Talay. More specifically,we consider approximations of the distribution and of thedensity of the solution of the stochastic differentialequation associated to the Mc Kean - Vlasov equation. Thescheme adopted here is a mixed one: Euler/weakly interactingparticle system. If $n$ is the number of weakly interactingparticles and $h$ is the uniform step in the timediscretization, we prove that the rate of convergence of thedistribution functions of the approximating sequence in the $L^1(\Omega\times \Bbb R)$ norm and in the sup norm is of theorder of $\frac 1{\sqrt n} + h $, while for the densities is ofthe order $ h +\frac 1 {\sqrt {nh}}$. This result is obtainedby carefully employing techniques of Malliavin Calculus.