An annotated list of the centipedes (Chilopoda) in the National Collection of Arachnids, Instituto de Biología, Universidad Nacional Autónoma de México : Addendum: Scutigeromorpha and Scolopendromorpha

This addendum to “An annotated list of the centipedes (Chilopoda) in The National Collection of Arachnids (Colección Nacional de Arácnidos, CNAN), Instituto de Biología, Universidad Nacional Autónoma de México” (México City), is based on new samples deposited in the last three years. It updates the preliminary list of 197 samples determined to genus and/or species. In this paper a total of 132 samples were added: Scutigeromorpha, 27; and Scolopendromorpha, 105. It also provides new state distribution records for Dendrothereua linceci (Wood, 1867), Scolopendra morsitans Linnaeus, 1758, S. polymorpha Wood, 1861, Rhysida immarginata (Porat, 1876), Scolopocryptops melanostomus Newport, 1845, Newportia spinipes Pocock, 1896, and Ectonocryptoides quadrimeropus Shelley and Mercurio, 2005.Adiciones a la “Lista anotada de ciempiés (Chilopoda) de la Colección Nacional de Arácnidos (CNAN) del Instituto de Biología de la Universidad Nacional Autónoma de México” (Ciudad de México), se realizaron a partir de la revisión de nuevas muestras depositadas en los últimos tres años. Con estas adiciones se actualiza la lista preliminar de 197 muestras determinadas a nivel de género y/o especie. En este trabajo se adicionan en total 132 muestras: Scutigeromorpha, 27; y Scolopendromorpha, 105. También se proporcionan nuevos registros de distribución estatal para Dendrothereua linceci (Wood, 1867), Scolopendra morsitans Linnaeus, 1758, S. polymorpha Wood, 1861, Rhysida immarginata (Porat, 1876), Scolopocryptops melanostomus Newport, 1845, Newportia spinipes Pocock, 1896, y Ectonocryptoides quadrimeropus Shelley y Mercurio, 2005

An annotated list of the centipedes (Chilopoda) in the National Collection of Arachnids, Instituto de Biología, Universidad Nacional Autónoma de México

The National Collection of Arachnids, Instituto de Biología, Universidad Nacional Autónoma de México (México City) houses 476 chilopod samples, of which 197 are determined to genus and/or species. These are documented here and represent several new state records. Topotypes of eight species of centipedes described by R. V. Chamberlin also documented.La Colección Nacional de Arácnidos, del Instituto de Biología de la Universidad Nacional Autónoma de México (Ciudad de México), resguarda 476 muestras de quilópodos, de los que 197 están determinadas a nivel de género y/o especie. Algunas de estas muestras corresponden a nuevos registros estatales. Se documentan los topotipos de ocho especies de ciempiés descritos por R. V. Chamberlin

A Red Tide Monitoring Program for Texas Coastal Waters

This is the final report for the red tide monitoring project conducted at The University of Texas at Austin Marine Science Institute (UTMSI) and covers the period from 1 Nov. 1998 to 10 April 2000. The study was designed to examine the seasonal dynamics of the toxic red tide dinoflagellate Karenia brevis (Davis) G. Hansen and Moestrup at 5 locations off the Texas coast. The work was conducted in collaboration with the Texas Parks and Wildlife Department (TPWD) utilizing bimonthly finfish surveys (Coastal Fisheries Division) to collect samples. The samples were shipped to UTMSI for chl a, nutrient, and cell count analyses. Significant interannual variability occurred in the temperature and salinity fields. Temperature was lowest in Jan.-Feb. of each year and increased. In general, the 5 stations showed little concordance with each other. There was no annual pattern in nutrient distributions. Individual stations appeared to reflect local inputs, rather than coast wide events. The only exception was a generalized silicate increase noted in Feb-April 2001 at all stations except Brazos Santiago near Brownsville. Karenia brevis was observed sporadically along the coast during the winter and most observations were limited to the summer/fall months. The sporadic occurrences and numerous "no cells" observations do not support the hypothesis that a year round resident red tide population exists in the Texas coastal zone. It appears that are transported into the area by large scale oceanographic features. The mechanism for this remains unknown. A minor red tide occurred along South Padre Island in Oct./Nov 1999. The bloom advected south into Mexico, and no further fish kills were noted in 1999. However, K. brevis occurred sporadically along the coast during this time. These events suggest that K. brevis may be seeded into the area from further offshore regularly at very low levels. Until fish-killing populations develop, it likely remains undetected. One major red tide event occurred during 2000 that affected the entire Texas coast. A small red tide occurred along South Padre Island in July, 2000 but disappeared after moving north to Padre Island National Seashore. Fish-killing concentrations of K. brevis were first detected in mid August off Sabine Pass in the north and moved south along the coast over the following months. However, low level occurrences of K. brevis were found at intermediate stations well before the main red tide advected into the region, and were nearly coincident with the initial observations off Sabine Pass. It is impossible from this data to determine if the July bloom in south Texas was related to the events off Sabine, but there is a possibility that offshore continental shelf currents may well be transporting cells north from Mexico into northern Texas waters. Another toxic species closely related to K. brevis has been seen at reasonably high abundance. This species, Karenia mikimotoi, is toxic to fish and has been reported to co-occur with K. brevis in blooms. Maximum abundance of this species was 6000 cells L-1, and appeared to exhibit a distinct increase and decline in population levels at 3 different stations.Marine Scienc

ICT and Cross-Country Comparisons: a Proposal of a New Composite Index

This paper focuses on the use and diffusion of Information and Communication Technologies (ICT) as a mechanism that may reduce the global divide between rich and poor countries. Our main contribution deals with the importance of counting with accurate time-series data and a precise assessment of the components that define ICT indicators at a national level. Thus, a multiple imputation technique is carried out to estimate ICT missing data under the expectation maximization approach. The resulting dataset allows us to propose a more confident estimation of an ICT composite index based on the notion of national capabilities, the called NaCap Index. A distinctive feature of the NaCap is that it attempts to capture countries’ differences on education and structural elements, both determinant factors to attain positive impacts from the use of ICT. The calculation of the Nacap Index for a broad sample of 170 countries and for a time spam from 1991 to 2003 enable us to do cross-country and time comparisons in a more robust manner.La idea de partida en este trabajo es que las tecnologías de la información y las comunicaciones (TIC), particularmente su uso y difusión, pueden resultar ser un mecanismo que contribuya a la disminución de la desigualdad existente entre países ricos y pobres en la era digital. Nuestra principal aportación está relacionada con la importancia que tiene la disponibilidad de información estadística para períodos extensos y mediciones más precisas de los distintos componentes que definen el nivel de acceso a las TIC de los países. Se recurre al uso de una técnica de imputación múltiple para estimar los datos ausentes de TIC y, a partir de esta estimación, se realiza la propuesta de un nuevo índice complejo de difusión de TIC que aporta una más adecuada cuantificación de las capacidades nacionales: el índice NaCap. Una de las características distintivas del NaCap es que intenta capturar el papel diferenciado de los distintos niveles de acceso a la educación en relación con la complejidad de las tecnologías y otros elementos estructurales de las economías, entendiéndolos como factores determinantes del impacto de las TIC en el desarrollo de los países. La estimación de los valores que adopta el índice NaCap en 170 países durante el período comprendido entre 1991 y 2003 permite la realización de análisis dinámicos así como acometer comparaciones internacionales más amplias y precisas que las que permite la información disponible en otras fuentes estadísticas internacionales.Difusión tecnológica, Adopción de tecnologías, Brecha digital, Indicadores compuestos, Imputación de datos, Technology diffusion, technology adoption, Digital divide, Composite indicators, Data imputation.

El paso de "dice que" a "dizque", de la referencia a la evidencialidad

El presente trabajo pretende explicar el proceso de gramaticalización del evidencial dizque y demostrar que la dirección de este cambio es de concreto a abstracto. El sistema genera estrategias para lograr la eficiencia comunicativa que pueden verse en la difusión del cambio. Con el propósito de analizar estas estrategias, se explica el proceso de gramaticalización de dizque y se examinan las consecuencias de la gramaticalización de este evidencial. Este análisis permite ver el proceso de cambio de dice que a dizque, de un sintagma con significado referencial a una palabra con un significado pragmático valorativo

Falsifying cosmological models based on a non-linear electrodynamics

Recently, the nonlinear electrodynamics (NED) has been gaining attention to generate primordial magnetic fields in the Universe and also to resolve singularity problems. Moreover, recent works have shown the crucial role of the NED on the inflation. This paper provides a new approach based on a new model of NED as a source of gravitation to remove the cosmic singularity at the big bang and explain the cosmic acceleration during the inflation era on the background of stochastic magnetic field. Also, we found a realization of a cyclic Universe, free of initial singularity, due to the proposed NED energy density. In addition, we explore whether a NED field without or with matter can be the origin of the late-time acceleration. For this we obtain explicit equations for $H(z)$ and perform a MCMC analysis to constrain the NED parameters by using $31$ observational Hubble data (OHD) obtained from cosmic chronometers covering the redshift range $0 < z < 1.97$; and with the joint-light-analysis (JLA) SNIa compilation consisting in $740$ data points in the range $0.01<z<1.2$. All our constraints on the current magnetic field give $B_{0}\sim 10^{-31}\mathrm{cm^{-1}}$, which are larger than the upper limit $10^{-33}\mathrm{cm^{-1}}$ by the Planck satellite implying that NED cosmologies could not be suitable to explain the Universe late-time dynamics. However, the current data is able to falsify the scenario at late times. Indeed, one is able to reconstruct the deceleration parameter $q(z)$ using the best fit values of the parameters obtained from OHD and SNIa data sets. If the matter component is not included, the data sets predict an accelerated phase in the early Universe, but a non accelerated Universe is preferred in the current epoch...Comment: 20 pages, two-column, 14 figures. Accepted for publication in the European Physical Journal

Thematic Regional Paper: Latin America

human development, climate change