Hard and Easy Instances of L-Tromino Tilings

We study tilings of regions in the square lattice with L-shaped trominoes. Deciding the existence of a tiling with L-trominoes for an arbitrary region in general is NP-complete, nonetheless, we identify restrictions to the problem where it either remains NP-complete or has a polynomial time algorithm. First, we characterize the possibility of when an Aztec rectangle and an Aztec diamond has an L-tromino tiling. Then, we study tilings of arbitrary regions where only $180^\circ$ rotations of L-trominoes are available. For this particular case we show that deciding the existence of a tiling remains NP-complete; yet, if a region does not contains certain so-called "forbidden polyominoes" as sub-regions, then there exists a polynomial time algorithm for deciding a tiling.Comment: Full extended version of LNCS 11355:82-95 (WALCOM 2019

Incidencia de los factores humanos y socioculturales en la captura de requerimientos: una revisión de la literatura

La actividad de captura de requerimientos es crítica para el desarrollo de software exitoso ya que cuando está bien ejecutada la probabilidad de obtener un software que cumpla con las necesidades de los usuarios aumenta, por el contrario, cualquier error cometido en esta etapa suele ser más costoso de sub-sanar posteriormente. Al mismo tiempo una parte importante de esta ejecución depende de las competencias que poseen las personas involucradas, del contexto en el que se desempeña y de los métodos o técnicas aplicados a tal fin. Por lo tanto, esta actividad puede verse afectada por factores no técnicos de índole individual o grupal. En este artículo se presenta una revisión sistemática de la literatura con el objetivo de conocer el estado del arte acerca de las propuestas existentes para la captura de requerimientos que contemplen factores humanos y socioculturales influyentes sobre esta actividad, así como también determinar qué adaptaciones se realizan en ese sentido.Sociedad Argentina de Informática e Investigación Operativ

II Jornadas de la Sociedad Española para la Conservación y Estudio de Los Mamíferos (SECEM) Soria 7-9 diciembre 1995

Seguimiento de una reintroducción de corzo (Capreolus capreolus) en ambiente mediterráneo. Dispersión y área de campeoModelos de distribución de los insectívoros ern la Península IbéricaDieta anual del zorro, Vulpes vulpes, en dos hábitats del Parque Nacional de DoñanaDesarrollo juvenil del cráneo en las poblaciones ibéricas de gato montés, Felis silvestris Schreber, 1777Presencia y expansión del visón americano (Mustela vison) en las provincias de Teruel y Castellón (Este de España).Preferencias de hábitat invernal de la musaraña común (Crocidura russula) en un encinar fragmentado de la submeseta norteUso de cámaras automáticas para la recogida de información faunística.Dieta del lobo en dos zonas de Asturias (España) que difieren en carga ganadera.Consumo de frutos y dispersión de semillas de serbal (Sorbus aucuparia L.) por zorros y martas en la cordillera Cantábrica occidentalEvaluación de espermatozoides obtenidos postmorten en el ciervo.Frecuencia de aparición de diferentes restos de conejo en excrementos de lince y zorroAtlas preliminar de los mamíferos de Soria (España)Censo y distribución de la marmota alpina (Marmota marmota) en Navarra.Trampeo fotográfico del género Martes en el Parque Nacional de Aigüestortes i Estany de Sant Maurici (Lleida)Peer reviewe

An estimate of the number of tropical tree species

The high species richness of tropical forests has long been recognized, yet there remains substantial uncertainty regarding the actual number of tropical tree species. Using a pantropical tree inventory database from closed canopy forests, consisting of 657,630 trees belonging to 11,371 species, we use a fitted value of Fisher’s alpha and an approximate pantropical stem total to estimate the minimum number of tropical forest tree species to fall between ∼40,000 and ∼53,000, i.e. at the high end of previous estimates. Contrary to common assumption, the Indo-Pacific region was found to be as species-rich as the Neotropics, with both regions having a minimum of ∼19,000–25,000 tree species. Continental Africa is relatively depauperate with a minimum of ∼4,500–6,000 tree species. Very few species are shared among the African, American, and the Indo-Pacific regions. We provide a methodological framework for estimating species richness in trees that may help refine species richness estimates of tree-dependent taxa

Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).

Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≥1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≤6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)

Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

Development of microservices-based applications: trends and research challenges

Los microservicios son un enfoque arquitectónico y organizativo del desarrollo de software en el que las aplicaciones están compuestas por pequeños servicios independientes que se comunican a través de un API bien definida y protocolos ligeros. En este trabajo se realizó una revisión de literatura para identificar los desafíos y tendencias de investigación presentes en las fases del proceso de desarrollo y en la gestión de atributos de calidad de este tipo de aplicaciones. Las tendencias se encuentran en la fase de desarrollo y en la fase de diseño; los atributos de calidad más estudiados son la escalabilidad y la calidad del servicio. Los desafíos de la investigación se centran en: definir el nivel de granularidad de los microservicios, modularización y refactorización de servicios, integración con la interfaz de usuario, seguridad, orquestación, monitoreo, gestión y supervisión de microservicios, tolerancia a fallas, recuperación y auto reparación de microservicios.Microservices are an architectural and organizational approach to software development in which applications are composed of small, independent services that communicate through a well-defined API and lightweight protocols. In this work, a literature review was carried out to identify the challenges and research trends present in the phases of the development process and in the management of quality attributes of this type of applications. The trends are in the development and design phase; the most studied quality attributes are scalability and quality of service. The research challenges focus on: defining the level of granularity of microservices, modularization and refactoring of services, integration with the user interface, security, orchestration, monitoring, management and supervision of microservices, fault tolerance, recovery and self-repair of microservices

Larvas de simulídeos (Diptera, Simuliidae) do centro oeste, sudeste e sul do Brasil, parasitadas por microsporídeos (Protozoa) e mermitídeos (Nematoda) Simulids larvae (Diptera, Simuliidae) from middle western, southeastern and southern Brazil, with microsporids (Protozoa) and mermithids (Nematoda) parasites

<abstract language="eng">A survey of simulid larval parasites was carried out in different localities of the states of Mato Grosso, Minas Gerais, São Paulo, Paraná, Santa Catarina and Rio Grande do Sul, Brazil, from February 1996 to May 1998. Prevalences for the microsporidian Polydispyrenia simulii Lutz & Splendore, 1908 were found in Morungaba and Leme, São Paulo, ranging from around 0.7 to 66.7%, depending mainly on the host simulid species. Microsporidiosis was registered in localities of São Paulo, Paraná, Santa Catarina and Rio Grande do Sul. Parasitism by Isomermis sp. (Nematoda, Mermithidae) was found in Simulium larvae from Serra do Japi, ranging from 0.8 to 45.8%, depending on the simulid species and the larval microhabitat in the stream, whether a cemented ramp in a lake outlet or the natural stream bed. Parasitism by mermithids was also found in ten localities. Mycoses caused by Coelomycidium sp. were for the first time recorded for larvae of Simulium (Chirostilbia) pertinax Kollar, 1832

Microservices backlog A genetic programming technique for identification and evaluation of microservices from user stories

The microservice granularity directly affects the quality attributes and usage of computational resources of the system, determining optimal microservice granularity is an open research topic. Microservices granularity is defined by the number of operations exposed by the microservice, the number of microservices that compose the whole application, and its complexity and dependencies. This paper describes “Microservice Backlog (MB)”, a semiautomatic model for defining and evaluating the granularity of microservice-based applications; MB uses genetic programming technique to calculate at design time the granularity of each microservice from the user stories in the “product backlog” or release planning; the genetic algorithm combined coupling, cohesion, granularity, semantic similarity, and complexity metrics to define the number of microservices, and the user stories associated with each microservice. MB decomposes the candidate microservices, allowing to analyze graphically the size of each microservice, as well as its complexity, dependencies, coupling, cohesion metrics, and the number of calls or requests between microservices. The resulting decomposition (number of microservices and their granularity) performed by MB shows less coupling, higher cohesion, less complexity, fewer user stories associated with each microservice, and fewer calls among microservices. MB was validated against three existing methods, using two state-of-the-art applications (Cargo Tracking and JPet-Store), and one real-life application (Foristom Conferences). The development team and/or architect can use metrics to identify the critical points of the system and determine at design time how the microservice-based application will be implemented