Length-weight relationship and relative condition factor of the Stone Scorpionfish Scorpaena mystes in the central area of the Gulf of California, Mexico

Background. In recent years (since 2012) there has been an increase in the commercial exploitation of Scorpaena mystes Jordan & Starks, 1985 in the central area of the Gulf of California and there is no information on the basic biology of this species that serve as a basis to determine the current population status and, in the future, assess any changes associated with exploitation and environmental factors. Goals. Determine the length-weight (LWR) and length-length (LLR) relationships, and the relative condition factor of S. mystes. Methods. Fish specimens (n = 258) were collected monthly from May 2015 through April 2016 in waters off Santa Rosalía, Baja California Sur. Each fish was measured for standard length (SL) and total length (TL), and weighed (W). Results. LWR and LLR were highly significant (p <0.05) with a determination coefficient higher than 0.9. The b-value (b = 3.06) of LWR was not significantly-different from 3. Monthly variation in the relative condition factor was also significant (p <0.05) with the highest value in August (1.34). Conclusions. The growth of S. mystes is isometric. The monthly variation in the condition factor may be associated with maturation of the gonads of the species.Background. In recent years (since 2012) there has been an increase in the commercial exploitation of Scorpaena mystes Jordan & Starks, 1985 in the central area of the Gulf of California and there is no information on the basic biology of this species that serve as a basis to determine the current population status and, in the future, assess any changes associated with exploitation and environmental factors. Goals. Determine the length-weight (LWR) and length-length (LLR) relationships, and the relative condition factor of S. mystes. Methods. Fish specimens (n = 258) were collected monthly from May 2015 through April 2016 in waters off Santa Rosalía, Baja California Sur. Each fish was measured for standard length (SL) and total length (TL), and weighed (W). Results. LWR and LLR were highly significant (p <0.05) with a determination coefficient higher than 0.9. The b-value (b = 3.06) of LWR was not significantly-different from 3. Monthly variation in the relative condition factor was also significant (p <0.05) with the highest value in August (1.34). Conclusions. The growth of S. mystes is isometric. The monthly variation in the condition factor may be associated with maturation of the gonads of the species

Distribución y estructura de comunidades de diatomeas en sedimentos de un sistema de manglar

The structure of diatom communities from the sediments bordering the mangrove forest was determined for two periods (cool and warm) in five sites of Zona de Canales, and in a sixth site in the San Carlos area within the Magdalena-Almejas lagoon system. 325 taxa were identified at the species, variety and form levels. The greater number of species were represented within the genera: Navicula (33), Amphora (31), Nitzschia (26), Cocconeis (16) y Lyrella (15). The surveyed communities are composed mainly by a mixture of episammic and epipelic taxa. The distribution of dominant (highly) abundant and abundant species was very much continuous, in both periods and sampling sites. Out of the 24 most important taxa in terms of their abundances and frequencies (BVI), eight occurred in both periods. Diversity values (H y 1-?) were high in the six sampling sites during the two periods and showed no significant differences (? = 0.05) by site or date of sampling. Although the San Carlos site did not vary significantly from Zona de Canales (ZC) sites, in terms of diversity, it does in its species composition. The absence of Lyrella and Mastogloia species from this site, while being conspicuous in ZC is underlined. The diatom assemblages in the mangrove sediments of ZC in Bahía Magdalena are characterized by high species richness and diversity, homogeneously distributed, both temporally and spatially.Se determinó la estructura de las comunidades de diatomeas en los sedimentos adyacentes al manglar, para dos períodos del año (frío y cálido), en cinco sitios de Zona de Canales dentro del Sistema Lagunar MagdalenaAlmejas, más uno, apartado, en el área de San Carlos. Se reconocieron un total de 325 taxa, a niveles de especie, variedad y forma. El mayor número de especies estuvo representado dentro de los géneros: Navicula (33), Amphora (31), Nitzschia (26), Cocconeis (16) y Lyrella (15). Las comunidades de diatomeas estuvieron compuestas principalmente por una mezcla de taxa episámicos y epipélicos. La distribución de las especies dominantes (muy abundantes) y abundantes resultó casi continua en los sitios de muestreo y en ambos periodos. De los 24 taxa más importantes numéricamente (IVB), ocho se presentaron en ambos períodos. Los valores de diversidad (H y 1-?) fueron elevados en los seis sitios de muestreo en ambos períodos y no variaron significativamente (? = 0.05) por sitio o fecha de muestreo. Aunque un sitio (San Carlos) no varió significativemente de los otros (Zona de Canales) en cuanto a diversidad, si difirió en la composición de especies. Destacó la ausencia de especies de Lyrella y Mastogloia en dicho sitio, mismas que fueron características de Zona de Canales. Las comunidades de diatomeas de sedimentos de manglar de Zona de Canales de Bahía Magdalena se distribuyen homogéneamente, espacial y temporalmente, y se caracterizan por una elevada riqueza y diversidad de especies

Species composition and assemblage structure of microfouling diatoms growing on fiberglass plates off the coast of Yucatán, Mexico

Background. It is generally accepted that exopolymer films secreted by diatoms promote the onset of macrofouling on surfaces of materials used in marine environments. However, few studies provide precise information at species level regarding the microfouling process. The use of anti-fouling paints on different surfaces to create a toxic environment may aid in precluding development of the initial diatom microfilm leading to macrofouling. Goals. To describe the species composition and the structure of fouling diatoms. Methods. We analyzed assemblages growing on fiberglass plates, coated and uncoated with antifouling paint, fixed on PVC stands submerged at a 10-m depth. Because diatoms are opportunistic, fast growing microalgae that proliferate on many substrates, our hypothesis was that diatom assemblages growing on fiberglass surfaces, coated or uncoated with antifouling paint, would not differ in their structure. Results. Floristic analysis yielded 170 diatom taxa and similar assemblages with high values of diversity occurring on both surfaces. Conclusions. In keeping with our hypothesis, both colonized fiberglass surfaces compare to living substrata that favor the growth of diatom associations that exhibit high species diversity. This information will be useful in environmental studies, such as pollution abatement, and for the design and maintenance of fishing boats and industrial equipment prone to biofouling.Background. It is generally accepted that exopolymer films secreted by diatoms promote the onset of macrofouling on surfaces of materials used in marine environments. However, few studies provide precise information at species level regarding the microfouling process. The use of anti-fouling paints on different surfaces to create a toxic environment may aid in precluding development of the initial diatom microfilm leading to macrofouling. Goals. To describe the species composition and the structure of fouling diatoms. Methods. We analyzed assemblages growing on fiberglass plates, coated and uncoated with antifouling paint, fixed on PVC stands submerged at a 10-m depth. Because diatoms are opportunistic, fast growing microalgae that proliferate on many substrates, our hypothesis was that diatom assemblages growing on fiberglass surfaces, coated or uncoated with antifouling paint, would not differ in their structure. Results. Floristic analysis yielded 170 diatom taxa and similar assemblages with high values of diversity occurring on both surfaces. Conclusions. In keeping with our hypothesis, both colonized fiberglass surfaces compare to living substrata that favor the growth of diatom associations that exhibit high species diversity. This information will be useful in environmental studies, such as pollution abatement, and for the design and maintenance of fishing boats and industrial equipment prone to biofouling

First record and geographic range extension of the coccolithophore Scyphosphaera apsteinii Lohman, 1902 (Haptophyta: Pontosphaeraceae) from the Pacific coast of Mexico

The coccolithophorid Scyphosphaera apsteinii is here reported for the first time from waters off the west coast of the Baja California Peninsula. Scypho­sphaera apsteinii is the type species of the genus Scyphosphaera and had hitherto been recorded only in the Atlantic and Indian Oceans, the Gulf of Mexico, the Mediterranean, and the Caribbean Seas. Specimens were found in samples collected in nets off Isla de Guadalupe in January 2013. This recording thus extends the geographical distribution of S. apsteinii from the Central Pacific (Hawaii) to the Eastern Pacific (NW Mexico)

Biovolumen ponderado; índice para estimar la contribución de especies en asociaciones de diatomeas bentónicas

With the purpose of deriving an alternative way for assessing the contribution of diatom taxa in benthic assemblages to biomass, the weighed biovolume index (WBV) is here proposed. The biovolumen (BV) was computed for taxa collected from intertidal mangrove sediments. The taxa were selected on the basis of total abundances (TA) and linear size. The TA and BV values showed an apparent inverse relation. In this way, the combined use of these variables is proposed (as WBV) as a more precise approximation to the contribution (as biomass) of each taxon in the assemblage. Thus, the WBV is computed as the product of the total abundances (TA) times the BV for each taxon, divided by the ? BV(AT) of all the taxa in the sample and expressed as percentage.Se propone el uso del biovolumen ponderado (BVP) de cada taxón, como una alternativa para medir la contribución a la biomasa, de los distintos taxa de diatomeas bentónicas de una asociación. Se determinó el biovolumen (BV) de taxa provenientes de sedimentos del intermareal en una zona de manglar; los taxa se seleccionaron con base en sus abundancias y su tamaño lineal. Los valores de BV y abundancia total (AT) mostraron una aparente relación opuesta. Consecuentemente, se propone el uso combinado de las AT y BV, en la forma de BVP, como mejor aproximación a la contribución (biomasa) de cada taxón en la asociación. Así, se definió el BVP como el producto del BV de un taxón por su abundancia, sobre la ? BV(AT) de todas las especies en la muestra, expresado en porcentaje

Primer registro de la diatomea Navicula lusoria para México y el Mar Caribe

Knowledge about benthic diatom flora in Mexico is partial and in many regions, among which the Mexican Caribbean stands, studies are lacking. Species belonging to the genus Navicula represent a challenge due to similarity in morphological and morphometric characters coupled with the limited information of morphological variation within populations by environmental changes. The aim of this study is to present the first record of Navicula lusoria to Mexico and the Caribbean Sea providing a description based on light and scanning electron microscopy. Navicula lusoria was observed as epipelic in brackish water in Xel-Há, Quintana Roo, hence, represents the expansion of the distribution range of this species. Although this species can easily be confused with Navicula digitoradiata, the original description of N. lusoria and the typification of N. digitoradiata allow to discriminate both species.En México el conocimiento de la flora de diatomeas bentónicas es parcial y para muchas regiones, entre las que destaca el Caribe Mexicano, prácticamente se carece de estudios. En particular, la determinación de las especies del género Navicula representa un reto debido a la similitud de las especies en sus caracteres morfológicos y morfométricos y a la poca información sobre la variación morfológica intrapoblacional causada por efectos ambientales. El objetivo de este trabajo es dar a conocer el primer registro de Navicula lusoria para México, particularmente para el mar Caribe, proporcionando su descripción con base en microscopia óptica y electrónica de barrido. Navicula lusoria se observó como epipélica en aguas salobres de la caleta de Xel-Há, Quintana Roo; por lo que este registro representa una ampliación del conocimiento sobre el área de distribución del taxon. Aunque esta especie puede ser fácilmente confundida con Navicula digitoradiata, la descripción original de N. lusoria y la tipificación de N. digitoradiata permiten discriminar adecuadamente ambas especies

Microangiopatía trombótica en el seno de una prostatitis aguda

We present the case of a 46-year-old man who was admitted to the hospital for an episode of acute prostatitis and who, during hospitalization, presented a progressive and severe deterioration of renal function accompanied by hemolytic anemia and severe thrombocytopenia. After an etiological study, a diagnosis of thrombotic microangiopathy was reached. Treatment with eculizumab and plasmapheresis was started with a good response.Presentamos el caso de un varón de 46 años que ingresó por un episodio de prostatitis aguda y durante la hospitalización presentó un deterioro progresivo y severo de la función renal acompañado de anemia hemolítica y trombocitopenia severa. Tras estudio etiológico se llegó al diagnóstico de una microangiopatía trombótica. Se inició tratamiento con eculizumab y plasmaféresis con buena respuesta

Macroalgas marinas bentónicas de Isla Gudalupe, Baja California, México

Background. The last floristic survey of marine algae species from Guadalupe Island was published in the 1980s, including a summary of surveys from collections dating back to the beginning of the past century. Goals. To update the species inventory and analyze the macroalgae community on Guadalupe Island. Methods. Four sampling procedures were undertaken, during January, April, and October 2013, and May 2014, from intertidal and subtidal zones, at depths of between 10 and 18m, depending on the locality. Results. 102 species were identified as representatives of the threemain taxonomic divisions; 14 species belonging to Chlorophyta, 29 to Ochrophyta, and 59 to Rhodophyta, related to 39 families and 65 genres. Of the organisms found at a specific level, 30 are new records, 13 are taxonomically synonymous, and 59 correspond to previous registries. The Margalef index shows that the highest biologic richness occurred in May 2014, as while the highest diversity also appeared in that same month, as the Shannon-Wiener index indicates. Data were statistically evaluated with the PERMANOVA analysis, showing statistical differences between the analyzed factors(depth, season, zone, and locality), thus demonstrating high heterogeneity at the localities, mainly between the northern and western areas of the island. Conclusions. Guadalupe Island has high species richness and diversity. In accordance to SIMPER analysis, the species that contribute most to the qualitative differences found in the analyzed factors are Zonaria farlowii, Jania rosea, Sargassum palmeri, Dictyopteris undulata, and Padina durvillei.Antecedentes. El último inventario florístico de algas marinas de Isla Guadalupe se publicó en la década de 1980, e incluye una recopilación de trabajos de colecciones de principios del siglo pasado. Objetivos. Realizar un inventario y un análisis actualizado de la comunidad de macroalgas de Isla Guadalupe. Métodos. Se efectuaron cuatro muestreos durante los meses de enero, abril y octubre del 2013 y mayo del 2014, en la zona intermareal y en la submareal, a 10 y 18 m de profundidad, dependiendo de la localidad. Resultados. En total se determinaron 102 especies, entre las que se encuentran representantes de las tres principales Divisiones taxonómicas: 14 especies de la División Chlorophyta, 29 especies de la División Ochrophyta y 59 especies de la División Rhodophyta, las cuales se relacionan con 39 familias y 65 géneros. De los organismos determinados a nivel específico, 30 corresponden a nuevos registros, 13 con sinonimia taxonómica y 59 especies están previamente registradas. De acuerdo con el índice de Margalef, durante mayo del 2014 se presentó la mayor riqueza biológica, en este mismo periodo, según el índice de Shannon-Wiener, se encontró una mayor diversidad. Los datos se analizaron estadísticamente con el análisis PERMANOVA, el cual mostró diferencias significativas entre los factores examinados de profundidad, temporada, zona y localidad de muestreo, lo que indica una alta heterogeneidad entre las localidades, principalmente entre la zona norte y la oeste de la isla. Conclusiones. Isla Guadalupepresenta una gran riqueza y diversidad biológica. De acuerdo con el análisis SIMPER, las especies que más contribuyen a las diferencias cualitativas de los factores analizados son Zonaria farlowii, Jania rosea, Sargassum palmeri, Dictyopteris undulata y Padina durvillei

The new multi-frequency instrument (MFI2) for the QUIJOTE facility in Tenerife

The QUIJOTE (Q-U-I joint Tenerife) experiment combines the operation of two radio-telescopes and three instruments working in the microwave bands 10?20 GHz, 26-36 GHz and 35-47 GHz at the Teide Observatory, Tenerife, and has already been presented in previous SPIE meetings (Hoyland, R. J. et al, 2012; Rubiño-Martín et al., 2012). The Cosmology group at the IAC have designed a new upgrade to the MFI instrument in the band 10-20 GHz. The aim of the QUIJOTE telescopes is to characterise the polarised emission of the cosmic microwave background (CMB), as well as galactic and extra-galactic sources, at medium and large angular scales. This MFI2 will continue the survey at even higher sensitivity levels. The MFI2 project led by the Instituto de Astrofísica de Canarias (IAC) consists of five polarimeters, three of them operating in the sub-band 10?15 GHz, and two in the sub-band 15-20 GHz. The MFI2 instrument is expected to be a full two-three times more sensitive than the former MFI. The microwave complex correlator design has been replaced by a simple correlator design with a digital back-end based on the latest Xilinx FPGAs (ZCU111). During the first half of 2019 the manufacture of the new cryostat was completed and since then the opto-mechanical components have been designed and manufactured. It is expected that the cryogenic front-end will be completed by the end of 2022 along with the FPGA acquisition and observing system. This digital system has been employed to be more robust against stray ground-based and satellite interference, having a frequency resolution of 1 MHz.The MFI2 instrument is being developed by the Instituto de Astrofisica de Canarias (IAC), with an instrumental participation from the Universidad Politecnica de Cartagena (UPCT). Partial financial support is provided by the Spanish Ministry of Science and Innovation (MICINN), under the projects AYA2017-84185-P, IACA15-BE-3707, EQC2018-004918-P and the FEDER Agreement INSIDE-OOCC (ICTS-2019-03-IAC-12). We also acknowledge financial support of the Severo Ochoa Programs SEV-2015-0548 and CEX2019-000920-S

Ética, hermenéutica y política. Filosofía en el fondo

Esta obra colectiva de ensayos académicos dictaminados, inspirados en el ciclo de conferencias Filosofía en el Fondo, ofrece una rica y entretejida lectura que, en cuatro secciones (La ética ante el problema del mal, Diferencia y alteridad, Hermenéutica de la modernidad, e Intersticios políticos), profundiza los problemas humanos que resisten el paso del tiempo desde enfoques hermenéuticos, genealógicos y críticos.ITESO, A.C