A geometrical view of scalar modulation instability in optical fibers

Full models of scalar modulation instability (MI) in optical fibers available in the literature usually involve complex formulations. In this paper, we present a novel approach to the analysis of MI in optical fibers by means of a simple geometrical description in the power vs. frequency plane. This formulation allows to relate the shape of the MI gain to any arbitrary dispersion profile of the medium, thus providing a simple insight. As a result, we derive a straightforward explanation of the non-trivial dependence of the cutoff power on high-order dispersion and derive explicitly the power that maximizes the gain. Our approach puts forth a tool to synthesize a desired MI gain with the potential application to a number of parametric-amplification and supercontinuum-generation devices whose initial-stage dynamics rely upon modulation instability.Fil: Hernandez, Santiago Martin. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; ArgentinaFil: Fierens, Pablo Ignacio. Instituto Tecnológico de Buenos Aires; ArgentinaFil: Bonetti, Juan Ignacio. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; ArgentinaFil: Sánchez, Alfredo Daniel. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; ArgentinaFil: Grosz, Diego Fernando. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Instituto Tecnológico de Buenos Aires; Argentin

External Shocks versus Domestic Policies in Emerging Markets

Debt crises in emerging markets have been linked to large fiscal deficits, high inflation rates, and large devaluations. This article studies a sovereign default model with domestic fiscal and monetary policies to understand Argentina’s experience during the 2000s commodity boom (2005–2017), following the default of 2001. The model suggests that domestic policies played a critical role in Argentina’s poor economic performance. Despite exceptionally favorable terms of trade, a rise in government spending led to higher taxation, inflation and currency depreciation, and lower output. Economic performance would have been worse had Argentina followed a strict, rather than accommodative, monetary policy without curbing its expansionary fiscal policy. Finally, limited access to international credit markets during this episode did not appear to play a significant role.Este artículo se encuentra publicado en Federal Reserve Bank of St. Louis Review, Second Quarter 2023, 105(2), pp. 108-21

Evolution of Andean structures in the Chos Malal fold and thrust belt: Interaction between the basement and the sedimentary cover of the Neuquén Basin

La faja corrida y plegada de Chos Malal se localiza al noroeste de la provincia de Neuquén e involucra más de 4.500 metros de sedimentos los cuales fueron depositados en la cuenca Neuquina y posteriormente deformados durante la orogenia Andina. En base a un detallado trabajo de campo se reconstruyó la geometría de las estructuras a lo largo de un perfil E-O en el cual se diferencian dos sectores: uno con la participación del basamento en la deformación y otro de deformación de la cubierta sedimentaria. La cordillera del Viento es una gran cuña que involucra el basamento paleozoico y a los Grupos Cuyo y Lotena, hasta alcanzar los niveles de yeso de la Formación Auquilco, los cuales constituyen el primer nivel de despegue. Este despegue, ubicado en un nivel más profundo que lo propuesto por otros autores, se evidencia por el cabalgamiento de parte de la Formación Tordillo sobre la Formación Vaca Muerta a través del retrocorrimiento El Alamito. Hacia el este de la cordillera del Viento, se reconocen en el perfil estructural cinco anticlinales, interpretados como pliegues por flexión y propagación de falla, con vergencia predominante hacia el este y subsidiaria hacia el oeste, los cuales presentan frecuentemente sus limbos frontales invertidos. Los anticlinales de mayor amplitud involucran a la Formación Tordillo y tienen como nivel de despegue las evaporitas de la Formación Auquilco. La restitución de las estructuras desarrolladas en la cubierta sedimentaria permitió calcular un acortamiento de 10 km (26%).The Chos Malal fold and thrust belt is located in northwestern Neuquén province and includes more than 4,500 meters of sediments that belong to the Neuquén Basin that were deformed during the Andean orogeny. Based in detailed field work, we reconstruct the geometry of the structures along an E-W cross-section which allow us to recognize two different sectors: one with the basement participation in the deformation and the other with deformation in the sedimentary cover. The cordillera del Viento is a huge basement wedge that involves paleozoics rocks and the Lotena and Cuyo Groups and reaches the levels Auquilco Formation, which represents the first significant detachment level in the cover. This detachment, localized on a more deep level than those proposed by other authors, is evidenced by the thrusting of Tordillo over Vaca Muerta Formation along the El Alamito backthrust. To the east of cordillera del Viento, five anticlines are recognized on the structural cross-section. They are interpreted as fault-bend and fault-propagation folds with predominantly vergence toward the east and subsidiary to the west, which have frequently frontals overturned limbs. The anticlines of greater amplitude involve the Tordillo Formation and have a detachment level along the evaporites of the Auquilco Formation. The restitution of the structures developed in the sedimentary cover allowed us to calculate of 10 km of shortening (26 %).Fil: Sánchez, Natalia Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Geológico del Sur; ArgentinaFil: Turienzo, Martin Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Geológico del Sur; ArgentinaFil: Dimieri, Luis Vicente. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Geológico del Sur; ArgentinaFil: Araujo, Vanesa Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Geológico del Sur; ArgentinaFil: Lebinson, Fernando Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Geológico del Sur; Argentin

Identification of seasonal variation in the diagnosis of acute myeloid leukaemia:a population-based study

Until now, the role that seasonal factors play in the aetiology of acute myeloid leukaemia (AML) has been unclear. Demonstration of seasonality in AML diagnosis would provide supportive evidence of an underlying seasonal aetiology. To investigate the potential seasonal and long‐term trends in AML diagnosis in an overall population and in subgroups according to sex and age, we used population‐based data from a Spanish hospital discharge registry. We conducted a larger study than any to date of 26 472 cases of AML diagnosed in Spain between 2004 and 2015. Using multivariable Poisson generalized linear autoregressive moving average modelling, we found an upward long‐term trend, with monthly incidence rates of AML annually increasing by 0.4% [95% confidence interval (CI), 0.2%–0.6%; p = 0.0011]. January displayed the highest incidence rate of AML, with a minimum average difference of 7% when compared to February (95% CI, 2%–12%; p = 0.0143) and a maximum average difference of 16% compared to November (95% CI, 11%–21%; p < 0.0001) and August (95% CI, 10%–21%; p < 0.0001). Such seasonal effect was consistent among subgroups according to sex and age. Our finding that AML diagnosis is seasonal strongly implies that seasonal factors, such as infectious agents or environmental triggers, influence the development and/or proliferation of disease, pointing to prevention opportunities

Measuring self-steepening with the photon-conserving nonlinear Schrödinger equation

We propose an original, simple, and direct method to measure self-steepening (SS) in nonlinear waveguides. Our proposal is based on results derived from the recently introduced photon-conserving nonlinear Schrödinger equation (NLSE) and relies on the time shift experienced by soliton-like pulses due to SS upon propagation. In particular, a direct measurement of this time shift allows for a precise estimation of the SS parameter. Furthermore, we show that such an approach cannot be tackled by resorting to the NLSE. The proposed method is validated through numerical simulations, in excellent agreement with the analytical model, and results are presented for relevant spectral regions in the near infrared, the telecommunication band, and the mid infrared, and for realistic parameters of available laser sources and waveguides. Finally, we demonstrate the robustness of the proposed scheme against deviations expected in real-life experimental conditions, such as pulse shape, pulse peak power, pulsewidth, and/or higher-order linear and nonlinear dispersion.Fil: Linale, Nicolás Martín. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Comision Nacional de Energia Atomica. Gerencia D/area Invest y Aplicaciones No Nucleares. Gerencia de Des. Tec. y Proyectos Especiales. Departamento de Ingenieria En Telecomunicaciones; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Fierens, Pablo Ignacio. Instituto Tecnológico de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bonetti, Juan Ignacio. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Comision Nacional de Energia Atomica. Gerencia D/area Invest y Aplicaciones No Nucleares. Gerencia de Des. Tec. y Proyectos Especiales. Departamento de Ingenieria En Telecomunicaciones; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Sánchez, Alfredo Daniel. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Comision Nacional de Energia Atomica. Gerencia D/area Invest y Aplicaciones No Nucleares. Gerencia de Des. Tec. y Proyectos Especiales. Departamento de Ingenieria En Telecomunicaciones; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Hernandez, Santiago Martin. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Universidad Nacional de Cuyo; ArgentinaFil: Grosz, Diego Fernando. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Comision Nacional de Energia Atomica. Gerencia D/area Invest y Aplicaciones No Nucleares. Gerencia de Des. Tec. y Proyectos Especiales. Departamento de Ingenieria En Telecomunicaciones; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentin

Zig-Zag Numberlink is NP-Complete

When can $t$ terminal pairs in an $m \times n$ grid be connected by $t$ vertex-disjoint paths that cover all vertices of the grid? We prove that this problem is NP-complete. Our hardness result can be compared to two previous NP-hardness proofs: Lynch's 1975 proof without the ``cover all vertices'' constraint, and Kotsuma and Takenaga's 2010 proof when the paths are restricted to have the fewest possible corners within their homotopy class. The latter restriction is a common form of the famous Nikoli puzzle \emph{Numberlink}; our problem is another common form of Numberlink, sometimes called \emph{Zig-Zag Numberlink} and popularized by the smartphone app \emph{Flow Free}

Analysis of vehicular traffic flow using a macroscopic model

Today the most cities in the world face different problems caused by vehicular traffic due to the increasing number of vehicles on road, such as traffic congestion, environmental pollution, excessive noise, increased accidents on the road, etc. Therefore it is important to represent the phenomenon by applying models so as to find better traffic flow patterns in a given city. In this work we introduce a simple macroscopic model to describe traffic flow in traffic congestion and we obtain the equation that relates the characteristic behavior between traffic flow and traffic density, known in the literature as fundamental relationship. Finally, we find an analytical solution for optimal flow passing vehicles on a congested road section

Structural Evolution of the Northern Agrio Fold and Trust Belt (∼37°30′S), Neuquén Basin, Argentina, Derived From Low‐Temperature Multi‐Thermochronometry

The Agrio Fold and Thrust Belt (FTB), situated in the Southern Central Andes at 37–39°S, underwent two phases of contractional deformation: Late Cretaceous‐Eocene and middle‐late Miocene. Despite advances in understanding its tectonic history, many questions persist regarding the timing and activity of specific structures during these deformation phases. By combining low‐temperature multi‐thermochronometry, inverse thermal models and field structural data, we present a new thermal‐structural history for the northern Agrio FTB. Our findings unveil an initial cooling event between approximately 85–75 Ma and 55–50 Ma, involving cooling rates of 1.1–2°C/Ma and vertical displacement rates from 0.07 to 0.12 km/Ma. This slow event, confined to the inner zone, is associated with the growth of the basement‐cored Manzano anticline. Additionally, still in the inner zone of the Agrio FTB, a second and faster cooling event from ∼15–10 Ma to 0 Ma, marked by a cooling rate of 7°C/Ma and a vertical displacement rate ranging from 0.11 to 0.17 km/Ma, results from in‐sequence thick‐skinned thrusting at depth. In the outer zone of the FTB, only the younger cooling event from 15–10 Ma to 0 Ma is evident, with a cooling rate of 8.8°C/Ma and a vertical displacement rate ranging from ∼0.14 to 0.26 km/Ma, attributed to displacement along the basement‐involved Las Yeseras thrust. Furthermore, Apatite Fission Track (AFT) ages of detrital grains in the Tralalhué conglomerates support the maximum depositional age for these synorogenic strata to be between 14.1 and 9.2 Ma.Fil: Sánchez, Natalia Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Coutand, Isabelle. Dalhousie University Halifax; CanadáFil: Turienzo, Martin Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Lebinson, Fernando Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Araujo, Vanesa Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Bordese, Sofia. Laboratorio de Termocronología; ArgentinaFil: Arzadún, Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; Argentina. Laboratorio de Termocronología; ArgentinaFil: Dimieri, Luis Vicente. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; Argentina. Laboratorio de Termocronología; Argentin

Drug-induced liver injury: A management position paper from the Latin American Association for Study of the liver

Idiosyncratic drug-induced liver injury (DILI) caused by xenobiotics (drugs, herbals and dietary supplements) is an uncommon cause of liver disease presenting with a wide range of phenotypes and disease severity, acute hepatitis mimicking viral hepatitis to autoimmune hepatitis, steatosis, fibrosis or rare chronic vascular syndromes. Disease severity ranges from asymptomatic liver test abnormalities to acute liver failure. DILI has been traditionally classified in predictable or intrinsic (dose-related) or unpredictable (not dose-related) mechanisms. Few prospective studies are assessing the real prevalence and incidence of hepatotoxicity in the general population. DILI registries represent useful networks used for the study of liver toxicity, aimed at improving the understanding of causes, phenotypes, natural history, and standardized definitions of hepatotoxicity. Although most of the registries do not carry out population-based studies, they may provide important data related to the prevalence of DILI, and also may be useful to compare features from different countries. With the support of the Spanish Registry of Hepatotoxicity, our Latin American Registry (LATINDILI) was created in 2011, and more than 350 DILI patients have been recruited to date. This position paper describes the more frequent drugs and herbs-induced DILI in Latin America, mainly focusing on several features of responsible medicaments. Also, we highlighted the most critical points on the management of hepatotoxicity in general and those based on findings from our Latin American experience in particular.Fil: Bessone, Fernando. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Hospital Nacional del Centenario; ArgentinaFil: Hernandez, Nelia. Hospital de Clinicas Dr. Manuel Quintela; UruguayFil: Tagle, Martin. Universidad Peruana Cayetano Heredia; PerúFil: Arrese, Marco. Pontificia Universidad Católica de Chile; ChileFil: Parana, Raymundo. Universidade Federal da Bahia; BrasilFil: Mendez-Sánchez, Nahum. Fundacion Clinica Medica Sur; México. Universidad Nacional Autónoma de México; MéxicoFil: Ridruejo, Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Mendizabal, Manuel. Universidad Austral. Hospital Universitario Austral; ArgentinaFil: Dagher, Lucy. Policlinica Metropolitana; VenezuelaFil: Contreras, Fernando. Universidad Pedro Henriquez Urena; República DominicanaFil: Fassio, Eduardo. Hospital Nacional Profesor Alejandro Posadas; ArgentinaFil: Pesoa, Mario. Hospital de Clincas; BrasilFil: Brahm, Javier. Clinica Las Condes; ChileFil: Silva, Marcelo. Universidad Austral. Hospital Universitario Austral; Argentin

Relationship between Prenatal or Postnatal Exposure to Pesticides and Obesity: A Systematic Review

In recent years, the worldwide prevalence of overweight and obesity among adults and children has dramatically increased. The conventional model regarding the onset of obesity is based on an imbalance between energy intake and expenditure. However, other possible environmental factors involved, such as the exposure to chemicals like pesticides, cannot be discarded. These compounds could act as endocrine-disrupting chemicals (EDC) that may interfere with hormone activity related to several mechanisms involved in body weight control. The main objective of this study was to systematically review the data provided in the scientific literature for a possible association between prenatal and postnatal exposure to pesticides and obesity in offspring. A total of 25 human and 9 animal studies were analyzed. The prenatal, perinatal, and postnatal exposure to organophosphate, organochlorine, pyrethroid, neonicotinoid, and carbamate, as well as a combined pesticide exposure was reviewed. This systematic review reveals that the effects of pesticide exposure on body weight are mostly inconclusive, finding conflicting results in both humans and experimental animals. The outcomes reviewed are dependent on many factors, including dosage and route of administration, species, sex, and treatment duration. More research is needed to effectively evaluate the impact of the combined effects of different pesticides on human health.This study was supported by grants from the Spanish Government (Ministerio de Economía y Competitividad and Instituto Mixto de Investigación-Escuela Nacional de Sanidad (IMIENS)) and the Fondo Europeo de Desarrollo Regional (MINECO-FEDER) Grant numbers: PSI2017-90806-REDT, PSI2017-83038-P, PSI2017-83893-R, PSI2017-86396-P, PSI2017-86847-C2-2-R MINECO-FEDER, and IMIENS: PIC-IMIENS-2018-003.S