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The Chemical Evolution of Narrow Emission Line Galaxies: the Key to their Formation Processes

JUAN PABLO TORRES PAPAQUI ROGER COZIOL RENE ALBERTO ORTEGA MINAKATA (2011)

Using the largest sample of narrow emission line galaxies available so far, we show that their spectral characteristics are correlated with different physical parameters, like the chemical abundances, the morphologies, the masses of the bulge and the mean stellar age of the stellar populations of the host galaxies. It suggests that the spectral variations observed in standard spectroscopic diagnostic diagrams are not due solely to variations of ionization parameters or structures but reflect also the chemical evolution of the galaxies, which in turn can be explained by different galaxy formation processes.

Utilizando la mayor muestra de galaxias con líneas de emisión angostas disponible hasta el momento, se muestra que sus características espectrales están correlacionadas con diferentes parámetros físicos, como las abundancias químicas, las morfologías, las masas del bulbo, y la edad estelar promedio de las poblaciones estelares de la galaxia anfitrio-na. Por lo tanto, se sugiere que las variaciones espectrales observadas en diagramas de diagnóstico estándares no se deben únicamente a las variaciones de los parámetros o las estructuras de ionización, sino que reflejan también la evolución química de las galaxias, relacionada con diferentes procesos de formación

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA Galaxy Chemical Activity Formation Chemical evolution Galaxias Actividad química Formación Evolución química

The cerato-mandibular ligament: a key functional trait for grazing in damselfishes (Pomacentridae)

Damien Olivier Bruno Frederich MILTON ALEJANDRO SPANOPOULOS ZARCO Eduardo Francisco Balart Páez Eric Parmentier (2014)

"The success of a taxonomic group can be promoted by a key character that allows the group to interact with its environment in a different way and to potentially occupy new niches. The Pomacentridae possess a synapomorphic trait, the cerato-mandibular (c-md) ligament, which joins the hyoid bar to the inner part of the lower jaw. It has previously been shown that this ligament is a key trait in communication in damselfishes because it enables them to slam the oral jaws shut causing teeth collision and sound production. This specific behavior of mouth closing could, however, also be used for other tasks, such as feeding. Many territorial damselfishes are referred to as farmers, due to their ability to manage algal crops on which they feed. This study hypothesizes that the c-md ligament provides an advantage for grazing filamentous algae, and should thus be considered a key trait for farming behavior."

Article

Biomechanics, Evolution, Farming, Functional morphology BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) ZOOLOGÍA MARINA ZOOLOGÍA MARINA

Evaluación del uso de vibriófagos encapsulados en el alimento para el control de Vibrio parahaemolitycus causante de AHPND en el camarón Penaeus vannamei

Esther Imelda Ponce García (2023)

"Las enfermedades causadas por bacterias del género Vibrio en el cultivo de camarón son de gran importancia debido a su impacto negativo en la industria acuícola. Estas bacterias pueden causar diversas enfermedades en camarones, como la necrosis hepatopancreática aguda (AHPND). La fagoterapia es una alternativa para el biocontrol de estas bacterias patógenas que presenta importantes ventajas, como la alta especificidad a sus huéspedes, la replicación en el sitio de infección, y la capacidad de infectar a bacterias resistentes a antibióticos. Sin embargo, la estabilidad de los fagos en el sistema de cultivo es una preocupación latente, ya que los fagos presentan una estabilidad limitada en solución y experimentan una caída significativa en el título de fagos durante el procesamiento y almacenamiento. El método de encapsulación de bacteriófagos, un área que aún no se estudia del todo, se presenta como una potencial alternativa para atender esta problemática. En el presente estudio se evaluó la eficacia terapéutica de un cóctel de bacteriófagos (vB_Vp_PvVp05, vB_Vp_PvVp07 y vB_Vp_PvVp11), encapsulados en alginato de sodio comercial y de mediana viscosidad, pectina, carboxilmetilcelulosa, liposomas y liofilizado en pectina como agente de biocontrol de Vibrio parahaemolyticus para su uso en terapias fagicas pasiva y activa. Se observó que el encapsulado en alginato de sodio de mediana viscosidad presentó la mayor liberación de fagos activos y al momento de ser incorporado a alimento para camarón y horneados a 80 – 100°C, se mantuvo una concentración de 1.3 x105 UFP/g después de 100 días de almacenamiento. Para la evaluación de las terapias pasiva y activa se realizó una infección experimental en juveniles de Penaeus vannamei para conocer la efectividad de los encapsulados, utilizando para la terapia pasiva la cepa Vp M0904 y para la activa la cepa Vp M0605. El experimento de terapia pasiva mostró una mortalidad del 80.6% en los camarones a las 48 hpi (p > 0.05) y una concentración de 5 x102 UFC/mL de Vibrio spp. no fermentativos en TCBS. En el caso de la terapia activa no se presentó mortalidades, pero hubo una disminución de la concentración de Vibrio spp. no fermentativos en TCBS con 5.56 x101 UFC/mL a las 48 hpi (p < 0.05) y aumentó la densidad de vibriófagos en 1.4 x102 UFP/mL en el agua de los acuarios (p < 0.05)..."

"Diseases caused by bacteria of the Vibrio genus in shrimp farming are of great importance due to their negative impact on the aquaculture industry. These bacteria can cause various diseases in shrimp, such as acute hepatopancreatic necrosis disease (AHPND). Phage therapy is an alternative for the biocontrol of these pathogenic bacteria, offering significant advantages, including high specificity to their hosts, replication at the infection site, and the ability to infect antibiotic-resistant bacteria. However, the stability of phages in the farming system is a persistent concern, as phages have limited stability in solution and undergo a significant drop in phage titer during processing and storage. The method of bacteriophage encapsulation, an area that is not yet fully explored, emerges as a potential alternative to address this issue. In this study, the therapeutic efficacy of a cocktail of bacteriophages (vB_Vp_PvVp05, vB_Vp_PvVp07, and vB_Vp_PvVp11), encapsulated in commercial medium-viscosity sodium alginate, pectin, carboxymethylcellulose, liposomes, and lyophilized pectin, was evaluated as a biocontrol agent against Vibrio parahaemolyticus for use in passive and active phage therapies. It was observed that encapsulation in medium-viscosity sodium alginate showed the highest release of active phages, maintaining a concentration of 1.3 x 105 PFU/g after 100 days of storage when incorporated into shrimp feed and baked at 80–100°C.For the evaluation of passive and active therapies, an experimental infection was conducted on Penaeus vannamei juveniles to assess the effectiveness of the encapsulated phages. The passive therapy experiment showed a mortality rate of 80.6% in shrimp at 48 hpi (p > 0.05) and a concentration of 5 x 102 CFU/mL of non-fermentative Vibrio spp. on TCBS agar. In the case of active therapy, no mortalities were observed, but there was a decrease in the concentration of non-fermentative Vibrio sp. on TCBS agar to 5.56 x 101 CFU/mL at 48 hpi (p < 0.05), and the density of vibriophages increased to 1.4 x 102 PFU/mL in the aquarium water (p < 0.05). It was determined that passive therapy offered no advantage for the control of Vibrio parahaemolyticus, unlike active therapy, which proved to be effective in controlling this bacterium."

Master thesis

vibriófagos, encapsulado, Penaeus vannamei, terapia activa, terapia pasiva vibriophages, encapsulated, active therapy, passive therapy BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA BACTERIÓFAGOS BACTERIÓFAGOS

Hot Extremes and Climatological Drought Indicators in the Transitional Semiarid-Subtropical Region of Sinaloa, Northwest Mexico

OMAR LLANES CARDENAS OSCAR GERARDO GUTIERREZ RUACHO Iván Hernández Romano ENRIQUE TROYO DIEGUEZ (2022)

"The main goal of this study was to explore the historical and recent spatial concurrence between the frequency (F), duration (D) and intensity (I) of hot extremes (HEs) and the frequency and evolution of meteorological drought in the region of Sinaloa. Based on the values of daily maximum temperatura (Tmax) and precipitation obtained from CLImate COMputing for the interval April–October of a historical period (1963–2000) and a recent period (1982–2014), the HE and the standardized precipitation index (SPI) were calculated on one-month (SPI-1) and four-month (SPI-4) timescales. Spearman rank correlation coefficients (Sr) were used to obtain the significant concurrences (SCs) between HEs and SPI-1, and HEs and SPI-4. El Quelite weather station showed the highest historical SCs between HEs and SPI-1 (−0.66≤Sr≤−0.57). Jaina is the only station that showed SCs with all four indicators of HEs and SPI-4 (−0.47≤Sr≤−0.34). In this study, the concurrence between HEs and SPI-1, and HEs and SPI-4 was determined for the first time. These are phenomena that can decrease the crop yield, particularly for rainfed crops such as maize, sesame and sorghum in the region commonly known as “the breadbasket of Mexico."

Article

frequency and evolution of meteorological droughts, the breadbasket of Mexico, Sinaloa CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO CLIMATOLOGÍA CLIMATOLOGÍA REGIONAL CLIMATOLOGÍA REGIONAL