On the existence of solution of the boundary-domain integral equation system derived from the 2D Dirichlet problem for the diffusion equation with variable coefficient using a novel parametrix

A system of boundary-domain integral equations is derived from the bidimensional Dirichlet problem for the diffusion equation with variable coefficient using a novel parametrix different from the one widely used in the literature by the authors Chkadua, Mikhailov and Natroshvili. Mapping properties of the surface and volume parametrix-based potential-type operators are analysed. Invertibility of the single layer potential is also studied in detail in appropriate Sobolev spaces. We show that the system of boundary-domain integral equations derived is equivalent to the Dirichlet problem prescribed and we prove the existence and uniqueness of solution in suitable Sobolev spaces of the system obtained by using arguments of compactness and Fredholm Alternative theory. A discussion of the possible applications of this new parametrix is included

Síndrome de insensibilidad completa a los andrógenos: reporte de un caso, ilustración del manejo quirúrgico

ResumenEl término “desorden en la diferenciación sexual” (DDS) representa un grupo de anormalidades en el desarrollo del tracto genitourinario, en el cual ocurre un desarrollo atípico en uno o más niveles: cromosómico, gonadal o anatómico. Los genéticamente varones 46XY pueden presentarse con genitales externos fenotípicamente femeninos o ambiguos. El síndrome de insensibilidad a los andrógenos se podría considerar una enfermedad causada por la resistencia a la acción androgénica, causada por la mutación Xq11-12, que afecta los receptores androgénicos; la presentación clínica dependerá del grado de insensibilidad, leve (masculino infértil), moderada o completa como en nuestro caso. Requiere seguimiento por psicólogo y psiquíatra para familiares y paciente, para un desarrollo psicosexual adecuado, antes y después del tratamiento quirúrgico definitivo.El objetivo del presente artículo es realizar una revisión sistemática de los artículos publicados en la base de datos de Medline, para identificar la epidemiología e incidencia del síndrome de insensibilidad completa a los andrógenos, así como reconocer su abordaje, tratamiento y seguimiento de estos casos.Se presenta paciente de 23 años de edad, sin antecedentes patológicos de importancia, la cual inicia su estudio a los 17 años de edad por el Servicio de Ginecología, por presentar amenorrea y falta de desarrollo en caracteres sexuales secundarios, tiene estudios de imagen sin evidenciar estructuras Müllerianas; se realiza laparoscopía diagnóstica en 2 ocasiones sin poder identificar órganos sexuales femeninos o vestigios de testículos; estudio hormonal con niveles de estrógenos y testosterona evidentemente bajos con hormona folículo estimulante (FSH), hormona luteinizante (LH) y hormona liberadora de gonadotropinas dentro de parámetros normales; el cariotipo reporta 46XY. En ese momento se ofrece apoyo psiquiátrico, se decide continuar con educación femenina, por lo que se resuelve colocación de prótesis mamaria. Finalmente, se nos interconsulta para la realización de vaginoplastía con uso de segmento intestinal como canal vaginal.AbstractThe term “disorders of sexual differentiation” (DSD) encompasses a group of abnormalities in the development of the genitourinary tract. Atypical development occurs at one or more chromosomal, gonadal, or anatomic levels. 46 XY genetic males may present with external genitals that are phenotypically female or ambiguous. Androgen insensitivity syndrome could be considered a disease caused by resistance to androgenic action due to the Xq11-12 mutation that affects the androgenic receptors. Clinical presentation depends on the degree of insensitivity: mild (infertile male), partial, or complete, as with our patient. Psychologic and psychiatric follow-up is required for both the patient and family members so there can be adequate psychosexual development before and after definitive surgical treatment.The aim of this article was to conduct a systematic review of published reports in the MEDLINE database to identify the epidemiology and incidence of complete androgen insensitivity syndrome and to examine the approach, treatment, and follow-up of these cases.We present herein a 23-year-old patient, with an unremarkable pathologic history, who began to be studied by the Gynecology Service at 17 years of age due to amenorrhea and lack of secondary sexual development. Imaging studies failed to show Müllerian structures. Diagnostic laparoscopy was performed on 2 occasions in which female sexual organs or vestiges of testes were unable to be identified. Hormonal study revealed obviously low levels of estrogens and testosterone, and follicle-stimulating hormone (FSH), luteinizing hormone (LH), and gonadotropinreleasing hormone were within normal parameters; 46XY karyotype was reported. Psychiatric support was then offered. It was decided that the patient would continue to be raised and treated as a female and therefore she was given breast implants. Our service was subsequently consulted for performing vaginoplasty using an intestinal segment as the vaginal canal

Síndrome de insensibilidad completa a los andrógenos: reporte de un caso, ilustración del manejo quirúrgico

ResumenEl término “desorden en la diferenciación sexual” (DDS) representa un grupo de anormalidades en el desarrollo del tracto genitourinario, en el cual ocurre un desarrollo atípico en uno o más niveles: cromosómico, gonadal o anatómico. Los genéticamente varones 46XY pueden presentarse con genitales externos fenotípicamente femeninos o ambiguos. El síndrome de insensibilidad a los andrógenos se podría considerar una enfermedad causada por la resistencia a la acción androgénica, causada por la mutación Xq11-12, que afecta los receptores androgénicos; la presentación clínica dependerá del grado de insensibilidad, leve (masculino infértil), moderada o completa como en nuestro caso. Requiere seguimiento por psicólogo y psiquíatra para familiares y paciente, para un desarrollo psicosexual adecuado, antes y después del tratamiento quirúrgico definitivo.El objetivo del presente artículo es realizar una revisión sistemática de los artículos publicados en la base de datos de Medline, para identificar la epidemiología e incidencia del síndrome de insensibilidad completa a los andrógenos, así como reconocer su abordaje, tratamiento y seguimiento de estos casos.Se presenta paciente de 23 años de edad, sin antecedentes patológicos de importancia, la cual inicia su estudio a los 17 años de edad por el Servicio de Ginecología, por presentar amenorrea y falta de desarrollo en caracteres sexuales secundarios, tiene estudios de imagen sin evidenciar estructuras Müllerianas; se realiza laparoscopía diagnóstica en 2 ocasiones sin poder identificar órganos sexuales femeninos o vestigios de testículos; estudio hormonal con niveles de estrógenos y testosterona evidentemente bajos con hormona folículo estimulante (FSH), hormona luteinizante (LH) y hormona liberadora de gonadotropinas dentro de parámetros normales; el cariotipo reporta 46XY. En ese momento se ofrece apoyo psiquiátrico, se decide continuar con educación femenina, por lo que se resuelve colocación de prótesis mamaria. Finalmente, se nos interconsulta para la realización de vaginoplastía con uso de segmento intestinal como canal vaginal.AbstractThe term “disorders of sexual differentiation” (DSD) encompasses a group of abnormalities in the development of the genitourinary tract. Atypical development occurs at one or more chromosomal, gonadal, or anatomic levels. 46 XY genetic males may present with external genitals that are phenotypically female or ambiguous. Androgen insensitivity syndrome could be considered a disease caused by resistance to androgenic action due to the Xq11-12 mutation that affects the androgenic receptors. Clinical presentation depends on the degree of insensitivity: mild (infertile male), partial, or complete, as with our patient. Psychologic and psychiatric follow-up is required for both the patient and family members so there can be adequate psychosexual development before and after definitive surgical treatment.The aim of this article was to conduct a systematic review of published reports in the MEDLINE database to identify the epidemiology and incidence of complete androgen insensitivity syndrome and to examine the approach, treatment, and follow-up of these cases.We present herein a 23-year-old patient, with an unremarkable pathologic history, who began to be studied by the Gynecology Service at 17 years of age due to amenorrhea and lack of secondary sexual development. Imaging studies failed to show Müllerian structures. Diagnostic laparoscopy was performed on 2 occasions in which female sexual organs or vestiges of testes were unable to be identified. Hormonal study revealed obviously low levels of estrogens and testosterone, and follicle-stimulating hormone (FSH), luteinizing hormone (LH), and gonadotropinreleasing hormone were within normal parameters; 46XY karyotype was reported. Psychiatric support was then offered. It was decided that the patient would continue to be raised and treated as a female and therefore she was given breast implants. Our service was subsequently consulted for performing vaginoplasty using an intestinal segment as the vaginal canal

Implications of Food Subsistence for Monetary Policy and Inflation

The chapter introduces subsistence requirements in food consumption into a simple New Keynesian model with flexible food and sticky non-food prices. It shows how the endogenous structural transformation that results from subsistence affects the dynamics of the economy, the design of monetary policy, and the properties of inflation at different levels of development. A calibrated version of the model encompasses both rich and poor countries and broadly replicates the properties of inflation across the development spectrum, including the dominant role played by changes in the relative price of food in poor countries. The authors derive a welfare-based loss function for the monetary authority and show that optimal policy calls for complete (in some cases near-complete) stabilization of sticky-price non-food inflation, despite the presence of a food-subsistence threshold. Subsistence amplifies the welfare losses of policy mistakes, however, raising the stakes for monetary policy at earlier stages of development.</p

Performance characterization of a multiplexed space-to-ground optical network

Advances in phased array systems for multi-beam free space optical communications are a key enabler for a new space-to-ground network architecture, namely a multiplexed optical architecture. The fundamental idea of a multiplexed space-to-ground optical network is the utilization of a multi-beam optical payload that allows each spacecraft to establish links with multiple ground stations within its line of sight. Information is then downlinked in parallel, from the satellite to the ground, through the subset of links not disrupted by clouds. In this paper we evaluate the performance of a multiplexed optical space-to-ground architecture from a systems perspective, with particular emphasis on the effect of cloud correlation in the network throughput. In particular, we first derive the expected data volume returned in a multiplexed architecture as a function of the optical network availability and the system total capacity. Then, we compare the performance of the proposed multiplexed architecture against a traditional single-beam downlink system that utilizes site diversity to mitigate cloud coverage effects. This comparison is based on two canonical scenarios, a global highly uncorrelated network representative of a geosynchronous satellite; and local, highly correlated, network representative of a low Earth orbit spacecraft. Through this analysis, we demonstrate that multiplexed architectures can improve the throughput of a space-to-ground optical network as compared to that of a single ground telescope without requiring a beam switching mechanism

Architecting space communication networks under mission demand uncertainty

NASAs Space Network has been a successful program that has provided reliable communication and navigation services for three decades. As the third generation of satellites is being launched, alternatives to the current architecture of the system are being studied in order to improve the performance of the system, reduce its costs and facilitate its integration with the Near Earth Network and the Deep Space Network. Within this context, past research has proven the feasibility of efficiently exploring a large space of alternative network architectures using a tradespace search framework. Architecting a space communication network is a complex task that requires consideration of uncertainty, namely (1) factoring in customer demand variability, (2) predicting technology improvements and (3) considering possible budgetary constraints. This paper focuses on adding uncertainty associated with (1) to the existing communications network architecture tool by describing a heuristic-based model to derive mission concept of operations (conops) as a function of communication requirements. The accuracy of the model is assessed by comparing real conops from current TDRSS-supported missions with the predicted concept of operations. The model is used to analyze how customer forecast uncertainty affects the choice of the future network architecture. In particular, four customer scenarios are generated and compared with the current TDRSS capabilities.United States. National Aeronautics and Space Administration (NNX11AR70G

Multivariate analysis of the reliability, availability, and maintainability characterizations of a Spar–Buoy wave energy converter farm

This is the final version of the article. Available from Springer via the DOI in this record.Quantitative reliability, availability, and maintainability (RAM) assessments are of fundamental importance at the early design stages, as well as planning and operation of marine renewable energy systems. This paper presents an RAM framework adaptable to different offshore renewable technologies, conceived to provide support in the choice of the device components and subsequent planning of the O&M strategies. A case study, characterizing a pilot farm of oscillating water column (OWC) wave energy converters (WECs), is illustrated together with the method used to obtain reliable estimate of its key performance indicators (KPIs). Based on a fixed feed-in-tariff for the project, economic figures are estimated, showing a direct relationship with the availability of the farm and the cost of maintenance interventions. Consequently, the probability distributions of the most relevant output variables are presented, and the mutual correlations between them investigated using principal components analysis (PCA) with the aim of discovering the relationships influencing the performance of the offshore farm. In this way, the contributions of the individual factors on the profitability of the project are quantified, and generic guidelines to support the decision-making process are derived. It is shown how this type of analysis provides important insights not only to ocean energy farm operators after the deployment of the devices, but also to device developers at the early design stage of wave energy concepts.The first and second authors were partially funded by the Marie Curie Actions of the European Union’s Seventh Framework Programme FP7/2007-2013/ under REA grant agreement number 607656 (OceaNet project). The fourth author was funded by FCT researcher grant No. IF/01457/2014. This work has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 654444 (OPERA Project) and from the FCT project PTDC/MAR-TEC/0914/2014