Factors influencing the abundance of pests in production fields and rates of interception of Dracaena marginata imported from Costa Rica.

Importation of live nursery plants, like Dracaena marginata Lamoureux (Ruscaceae), can provide a significant pathway for the entry of foliar pests from overseas into the United States. We studied the abundance of foliar pests of quarantine importance found on Costa Rican-grown D. marginata. These include five genera of leafhoppers (Heteroptera: Cicadellidae, Oncometopia, Caldweliola, Diestostema, Cypona, and Empoasca), Florida red scale (Heteroptera: Disapididae, Chrysomphalus aoinidum (L.)), katydids (Orthoptera: Tettigoniidae), and a snail (Succinea costarricana von Martens (Gastropoda, Stylommatophora, Succineidae)). In our first study, we examined the rationale behind size restrictions on Dracaena cuttings imported into the United States from Costa Rica. When comparing plant size, no differences were found in the abundance of quarantined pests on small (15-46 cm), medium (46-81 cm), and large (81-152 cm) propagules. In a second study, we estimated monthly abundances of pests in production plots for 1 yr to determine their relationship to rates of interception at U.S. ports. In any given month, < 6% of the marketable shoots standing in the field were infested with at least one quarantine pest. There was no relationship between the average monthly frequencies of pest detection in the field and in U.S. inspection ports. Pest detections increased during the 1 mo when average monthly shipments were abnormally high. Our data suggest that off-shore postprocessing efforts to remove pest-infested material from the market stream need to be adjusted to accommodate sharp increases in the volume of shipped plants.

A Survey of Vectorization Methods in Topological Data Analysis.

Attempts to incorporate topological information in supervised learning tasks have resulted in the creation of several techniques for vectorizing persistent homology barcodes. In this paper, we study thirteen such methods. Besides describing an organizational framework for these methods, we comprehensively benchmark them against three well-known classification tasks. Surprisingly, we discover that the best-performing method is a simple vectorization, which consists only of a few elementary summary statistics. Finally, we provide a convenient web application which has been designed to facilitate exploration and experimentation with various vectorization methods.

Optimizing the Simplicial-Map Neural Network Architecture.

Simplicial-map neural networks are a recent neural network architecture induced by simplicial maps defined between simplicial complexes. It has been proved that simplicial-map neural networks are universal approximators and that they can be refined to be robust to adversarial attacks. In this paper, the refinement toward robustness is optimized by reducing the number of simplices (i.e., nodes) needed. We have shown experimentally that such a refined neural network is equivalent to the original network as a classification tool but requires much less storage.

Burrow systems evince non-solitary geomyid rodents from the Paleogene of southern Mexico.

We describe a new complex burrow system produced by geomyids in southern Mexico. Yaviichnus inyooensis igen. isp. nov. is composed of main large chambers near the top of the paleosol, from which shafts showing different morphologies and orientations radiate, some of them ending in or connected to small deeper chambers. Gregorymys spp. is proposed as the producer based on its fossorial habits, abundance in the outcrops, presence of remains inside the burrows, and paired grooves in the walls, which are compatible with the traces of geomyid incisors. The complexity of these burrows attests to an extended underground life that would have been triggered by semiarid to arid conditions. Morphological complexity also suggests that the burrows were excavated and inhabited by more than one individual, indicating that Oligocene Gregorymys of southern Mexico would be a unique gregarious geomyid.

Two-hidden-layer feed-forward networks are universal approximators: A constructive approach.

It is well-known that artificial neural networks are universal approximators. The classical existence result proves that, given a continuous function on a compact set embedded in an n-dimensional space, there exists a one-hidden-layer feed-forward network that approximates the function. In this paper, a constructive approach to this problem is given for the case of a continuous function on triangulated spaces. Once a triangulation of the space is given, a two-hidden-layer feed-forward network with a concrete set of weights is computed. The level of the approximation depends on the refinement of the triangulation.

Effects of weed cover composition on insect pest and natural enemy abundance in a field of Dracaena marginata (Asparagales: Asparagaceae) in Costa Rica.

Weeds and their influence on pest and natural enemy populations were studied on a commercial ornamental farm during 2009 in the Atlantic Zone of Costa Rica. A baseline survey of the entire production plot was conducted in February, along a 5 by 5 m grid to characterize and map initial weed communities of plants, cicadellids, katydids, and armored scales. In total, 50 plant species from 21 families were found. Seven weed treatments were established to determine how weed manipulations would affect communities of our targeted pests and natural enemies. These treatments were selected based on reported effects of specific weed cover on herbivorous insects and natural enemies, or by their use by growers as a cover crop. Treatments ranged from weed-free to being completely covered with endemic species of weeds. Although some weed treatments changed pest abundances, responses differed among arthropod pests, with the strongest effects observed for Caldwelliola and Empoasca leafhoppers. Removal of all weeds increased the abundance of Empoasca, whereas leaving mostly cyperacaeous weeds increased the abundance of Caldwelliola. Weed manipulations had no effect on the abundance of katydid and scale populations. No weed treatment reduced the abundance of all three of the target pests. Differential responses of the two leafhopper species to the same weed treatments support hypotheses, suggesting that noncrop plants can alter the abundance of pests through their effects on arthropod host finding and acceptance, as well as their impacts on natural enemies.

Comportamiento epidemiológico de la histerectomía obstétrica / Epidemiological behavior of obstetric hysterectomy

Introducción: la histerectomía obstétrica es una medida quirúrgica drástica que se realiza en aquellas pacientes que no responden a otros procedimientos, frente a una hemorragia severa después de un parto o cesárea.Objetivos: caracterizar la distribución de un conjunto de variables en gestantes que requirieron una histerectomía obstétrica posparto, describir sus características clínicas y obstétricas e identificar las principales variables epidemiológicas en relación con el periparto y parto.Métodos: se realizó una investigación descriptiva, retrospectiva, de 19 gestantes a las cuales se les practicó histerectomía obstétrica por diferentes causas, atendidas en el Servicio de Partos del Hospital Ginecobstétrico Docente Ramón González Coro, en el período comprendido entre el 1ro. de enero de 2009 hasta el 31 de diciembre de 2010. Se utilizó la base de datos confeccionada a través del Sistema Microsoft Excel 2007. El estudio se efectuó conforme a las reglamentaciones y principios éticos existentes para la investigación en humanos y los estudios clínicos.Resultados: el mioma uterino se observó en el 26,3 porciento; el 31,6 porciento fueron nulíparas; predominó en pacientes con cesárea primitiva en un 42,1 porciento; el 66,7 porciento fue debido a atonía uterina y fue necesario el uso de prostaglandinas en el 31,6 porciento de los casos.Conclusiones: las complicaciones relacionadas con la cesárea y la atonía uterina siguen constituyendo las causas fundamentales de indicación de la histerectomía obstétrica

Introduction: obstetric hysterectomy is a surgical drastic measure performed in those patients who do not respond to other procedures, in case of severe bleeding after childbirth or caesarean.Objectives: to characterize the distribution of a set of variables in pregnant women requiring obstetric postpartum hysterectomy, to describe their clinical and obstetric characteristics and to identify key epidemiological variables relating to peri-delivery and delivery.Methods: a descriptive, retrospective study was conducted in 19 pregnant women who underwent obstetric hysterectomy for various reasons at the delivery service in Ramón González Coro Hospital, from 1st January 2009 to 31 December 2010. A database created through Microsoft Excel System 2007 was used. The study was conducted in accordance with existing regulations and ethical principles for human research and clinical studies.Results: uterine myoma was observed in 26.3 per cent, and it was predominant in patients with early cesarean in 42.1 per cent, 31.6 per cent were nulliparous, 66.7 per cent was caused by uterine atony and the use prostaglandin was necessary in 31.6 per cent of cases.Conclusions: complications associated with cesarean section and uterine atonies remain the root causes of obstetric hysterectomy indication

Sex pheromone of the scarab beetle Phyllophaga elenans and some intriguing minor components.

Three amino acid-derived compounds were identified in extracts from the pheromone glands of the scarab beetle Phyllophaga elenans, i.e., L-isoleucine methyl ester (LIME), N-formyl L-isoleucine methyl ester (For-LIME), and N-acetyl L-isoleucine methyl ester (Ac-LIME). The compounds were characterized from their spectral data (MS and IR), confirmed by synthesis, and their absolute configurations were assigned by gas chromatography with a chiral phase column. The amount of LIME in calling females was ca. 2 microg/gland, whereas only traces of For-LIME and Ac-LIME (0.005% of LIME) were detected in fresh extracts. Regardless of the storage temperature, the amounts of the minor constituents in the extracts increased overtime. Field tests showed that traps baited with For-LIME captured more beetles than control traps. Ac-LIME per se was not attractive, and it did not increase trap catches when combined with For-LIME. Traps baited with LIME caught ca. 150 beetles/trap/day, but catches did not increase with the addition of For-LIME and/or Ac-LIME in binary or tertiary blends.

Valoración de ketotifeno en el tratamiento de asma bronquial en niños y adultos / Evaluation of ketotifen in the treatment of bronchial asthma in children and adults

Con objeto de valorar la eficacia de ketotifeno, fármaco antialérgico, para prevenir las crisis asmáticas, se incluyó en un estudio clínico abierto a 20 pacientes, adultos y niños de ambos sexos. Se administró ketotifeno en dosis de 0.5 mg a 1 mg cada 12 horas dependiendo de la edad del paciente, y se valoraron los parámetros de frecuencia, intensidad y duración de las crisis asmáticas al inicio del estudio y a las cuatro, ocho y 12 semanas. Se observó disminución en los 3 parámetros estudiados, y sólo un caso de los 20 no mostró respuesta positiva al tratamiento, ya que se trataba de una niña con asma grave de origen intrínseco. Sin embargo, cinco casos de asma de origen mixto y dos de origen intrínseco respondieron adecuadamente a ketotifeno, además de los pacientes con asma extrínseca. El único efecto indeseable que se presentó fue somnolencia en 55% de pacientes, y disminuyó paulatinamente durante el tratamiento observándose al final del estudio sólo en 20% de los pacientes estudiados

Las malformaciones congénitas en hijos de madres diabéticas (estudio de 1 064 nacimientos consecutivos): II parte y final / Congenital malformation in children of diabetic mothers (study of 1 064 consecutive birts): part II

Se estudia la frecuencia de malformaciones congénitas en 1 064 nacimientos consecutivos de madres dibéticas en el período de 1973 a 1988, ambos inclusive. Fueron catalogadas 519 embarazadas de diabéticas pregestacionales. No se utilizaron en toda la serie compuestos orales hipoglicemiantes. En el período 1973-1975 se utilizó el tratamiento insulínico descrito por Roversi y a partir de 1976 se utilizó el propuesto por los profesores Valdés Amador y Márquez Guillén. Se realizó necropsia en el 100 %de las defunciones. Encontramos una reacción positiva entre la lesión vascular materna y la frecuencia de malformaciones en los hijos de madres diabéticas pregestacionales; sin embargo, probablemente debido al trastorno metabólico primario el crecimiento intrauterino retardado no se vió significativamente presente en los fetos y neonatos mal conformados. Se concluye que las malformaciones incompatibles con la vida tienen severa repercusión en la tasa de mortalidad perinatal de estas embarazadas