The intensification of coastal hypoxia off central Chile: Long term and high frequency variability

Hypoxia is a phenomenon where dissolved oxygen (DO) is reduced to levels that are low enough to strongly affect ecological and biogeochemical processes. This occurs within the continental shelf off central Chile (36°S), influenced by seasonal coastal upwelling (Spring-Summer). Monthly measurements of DO and other oceanographic variables in the water column (1997−2021) over the 92 m isobath along with high-resolution and near-surface observations (POSAR buoy), are analyzed to examine incidences of hypoxia and understand the physical and biogeochemical processes modulating DO vertical distribution and its temporal variability. On average, the percentage of the water column with DO levels below 89 (hypoxia) and 22 (severe hypoxia) μmol L−1 reaches 68% (i.e., hypoxic waters are found below 30 m) and 44% (below 50 m depth), respectively, but during the upwelling season, as much as 87% (below 12 m depth) and 81% (below 17 m depth) of the water column exhibits these levels. On the sub-seasonal scale during upwelling season six hypoxic events lasting at least 2 days occur at 10 m depth. There is a strong seasonal correlation between the volume of the seawater presenting hypoxia and upwelling favorable winds. Furthermore, there is a high DO interannual variability partially related to the El Niño Southern Oscillation (ENSO). Over 2 decades, it is estimated that DO concentration in surface and subsurface layers decreases (up to 21 μmol L−1 decade−1) as waters get colder (up to 0.29°C decade−1). Remarkably, the volume of hypoxic and severe hypoxic waters over the shelf has increased more than 2 times since 1997 and shows a significant positive correlation with the upwelling index. These preliminary findings indicate that the increase in local DO consumption is partially associated with upwelling intensification. Given the clear evidence of wind intensification in coastal upwelling ecosystems and thus the increase in hypoxic events, the coastal zone may be highly vulnerable to hypoxia, impacting biological resources and biogeochemical cycles

The influence of anoxia and substrate availability on N2O cycling by denitrification in the upper boundary of the oxygen minimum zone off northern Chile

Strong accumulations of N2O at oxyclines are some of the most conspicuous features of the world\u27s oceans. However, the origin of these maxima, and the relative contribution of nitrification and denitrification in N2O cycling, remains unclear. In order to gain insight into the importance of denitrification and factors regulating N2O cycling at upper oxyclines in the eastern South Pacific, the production and consumption of N2O by denitrification were measured using a classical acetylene method under induced anoxia with the addition of an electron acceptor (nitrite) and donors (sodium acetate and glucose). The results indicated that decreased O2 clearly affected the ratio in which N2O is reduced to N2 at the midoxycline (∼40 m depth) and at the oxycline\u27s base (∼80 m depth). Under induced anoxia, higher N2O production (from NO–2 to N2O of 67.2 nM d–1) occurred at 40 m depth, with half of the total quantity being consumed by denitrification (from N2O to N2 of 32 nM d–1); conversely, 100% of the N2O was reduced to N2 at 80 m depth. In comparison with previously reported results at the base of the oxycline at an offshore station, the addition of NO–2 (as sodium nitrite) along with dissolved organic carbon (as sodium acetate and glucose) doubled the net N2O production by denitrification (∼20 nM d–1). Our results suggest that decreasing O2 levels along with an increased availability of NO–2 and organic compounds in the upper oxycline may impact the N2O/N2 ratio and, therefore, the N2O efflux to the atmosphere

Nitrogen Fixation in Denitrified Marine Waters

Nitrogen fixation is an essential process that biologically transforms atmospheric dinitrogen gas to ammonia, therefore compensating for nitrogen losses occurring via denitrification and anammox. Currently, inputs and losses of nitrogen to the ocean resulting from these processes are thought to be spatially separated: nitrogen fixation takes place primarily in open ocean environments (mainly through diazotrophic cyanobacteria), whereas nitrogen losses occur in oxygen-depleted intermediate waters and sediments (mostly via denitrifying and anammox bacteria). Here we report on rates of nitrogen fixation obtained during two oceanographic cruises in 2005 and 2007 in the eastern tropical South Pacific (ETSP), a region characterized by the presence of coastal upwelling and a major permanent oxygen minimum zone (OMZ). Our results show significant rates of nitrogen fixation in the water column; however, integrated rates from the surface down to 120 m varied by ∼30 fold between cruises (7.5±4.6 versus 190±82.3 µmol m−2 d−1). Moreover, rates were measured down to 400 m depth in 2007, indicating that the contribution to the integrated rates of the subsurface oxygen-deficient layer was ∼5 times higher (574±294 µmol m−2 d−1) than the oxic euphotic layer (48±68 µmol m−2 d−1). Concurrent molecular measurements detected the dinitrogenase reductase gene nifH in surface and subsurface waters. Phylogenetic analysis of the nifH sequences showed the presence of a diverse diazotrophic community at the time of the highest measured nitrogen fixation rates. Our results thus demonstrate the occurrence of nitrogen fixation in nutrient-rich coastal upwelling systems and, importantly, within the underlying OMZ. They also suggest that nitrogen fixation is a widespread process that can sporadically provide a supplementary source of fixed nitrogen in these regions

Entanglement breaking channels and entanglement sudden death

The occurrence of entanglement sudden death in the evolution of a bipartite system depends on both the initial state and the channel responsible for the evolution. An extreme case is that of entanglement braking channels, which are channels that acting on only one of the subsystems drives them to full disentanglement regardless of the initial state. In general, one can find certain combinations of initial states and channels acting on one or both subsystems that can result in entanglement sudden death or not. Neither the channel nor the initial state, but their combination, is responsible for this effect, but their combination. In this work we show that, in all cases, when entanglement sudden death occurs, the evolution can be mapped to that of an effective entanglement breaking channel on a modified initial state. Our results allow to anticipate which states will suffer entanglement sudden death or not for a given evolution. An experiment with polarization entangled photons demonstrates the utility of this result in a variety of cases

Cambiemos y la Modernización del Estado Argentino: ¿Realidad o Ficción?

As a result of its recent emergence in Argentina and within the framework of a doctoral research process, the article analyzes the different strategies and devices implemented by Senior Public Managers who, having been directors of large companies, were designated as the main articulators of The State Modernization Plan during the period of government of the Cambiemos coalition (2015-2019). Therefore, it will seek to publicize the characteristics of the modernization project, the principles and values ​​that governed public employees and the implemented devices that sought to influence state subjectivity.Producto de su reciente surgimiento en Argentina y en el marco de un proceso de investigación doctoral, el artículo analiza las diferentes estrategias y dispositivos implementados por una serie de Altos Funcionarios que, habiendo sido directivos de grandes empresas, fueron designados como los principales articuladores del Plan de Modernización del Estado durante el período de gobierno de la coalición Cambiemos (2015-2019). Se buscará, por lo tanto, dar a conocer las características del proyecto de modernización, los principios y valores que rigieron para los empleados públicos y los dispositivos implementados que buscaron influir en la subjetividad estatal

Cambiemos and Argentine State Modernization: Reality or Fiction?

Producto de su reciente surgimiento en Argentina y en el marco de un proceso de investigación doctoral, el artículo analiza las diferentes estrategias y dispositivos implementados por una serie de Altos Funcionarios que, habiendo sido directivos de grandes empresas, fueron designados como los principales articuladores del Plan de Modernización del Estado durante el período de gobierno de la coalición Cambiemos (2015-2019). Se buscará, por lo tanto, dar a conocer las características del proyecto de modernización, los principios y valores que rigieron para los empleados públicos y los dispositivos implementados que buscaron influir en la subjetividad estatal.As a result of its recent emergence in Argentina and within the framework of a doctoral research process, the article analyzes the different strategies and devices implemented by Senior Public Managers who, having been directors of large companies, were designated as the main articulators of The State Modernization Plan during the period of government of the Cambiemos coalition (2015-2019). Therefore, it will seek to publicize the characteristics of the modernization project, the principles and values that governed public employees and the implemented devices that sought to influence state subjectivity.Facultad de Periodismo y Comunicación Socia

Diagnóstico del virus Distemper y Parvovirus canino a través de kits rápidos y qPCR en la ciudad de Latacunga

Distemper and canine Parvovirus, which are highly contagious diseases that affect any age dogs, although their incidence is higher in the less than one-year-old. The reliable diagnosis and opportune treatment improve the infected animals´ prognostic. So, it was compared the Distemper and canine Parvovirus diagnosis between the qPCR molecular test and the quick kits into domestic canines’ clinical cases, which come to veterinary centers in Latacunga city. It was analyzed 24 canine parvovirus samples, which 19 samples were positive to quick kits, they were found that 5 parvovirus samples diagnosed by quick kits with negative results were positive by real-time PCR, on the other hand 4 positive parvovirus samples per quick kits gave negative results to qPCR, this proves that it is a highly sensitive and highly specificity technique for virus detection, unlike quick kits. With canine Distemper there were problems by the standardization process, but from 6 positive Distemper samples diagnosed through quick kits, 2 gave positive qPCR results. The research results allow to set that qPCR is a recommended diagnostic technique for the Parvovirus and canine Distemper detection, since the results obtained by this technique are more reliable and faster. The quick tests used into the veterinary clinic that into this and other studies have shown their low sensitivity consistentlyDistemper y Parvovirus canino son enfermedades altamente contagiosas que afectan a perros de cualquier edad, aunque su incidencia es más alta en aquellos menos de un año. El diagnóstico confiable y tratamiento oportuno mejoran el pronóstico de los animales infectados. Por lo tanto, se comparó el diagnóstico del Distemper y Parvovirus canino entre la prueba molecular qPCR y los kits rápidos en casos clínicos de caninos domésticos, que acuden a los centros Veterinarios en la ciudad de Latacunga. Se analizaron 24 muestras de parvovirus canino de los cuales 19 muestras resultaron positivas a kits rápidos, se encontraron que 5 muestras de parvovirus diagnosticada por kits rápidos de resultados negativos dieron positivas a PCR en tiempo real, por otro lado 4 muestras de parvovirus positivas por kits rápidos dieron resultados negativos a qPCR esto comprueba que es una técnica altamente sensible y de alta especificidad para la detección del virus, a diferencia de los kits rápidos. Con Distemper canino hubo problemas con el proceso de estandarización, pero de las 6 muestras positivas de Distemper diagnosticadas por kits rápidos 2 dieron resultados positivos a qPCR. Los resultados de esta investigación permiten establecer que la qPCR es una técnica de diagnóstico recomendable para la detección de Parvovirus y Distemper canino, los resultados obtenidos mediante esta técnica son de mayor confianza y rapidez. Las pruebas rápidas utilizadas en la consulta veterinaria que en este y otros estudios han mostrado constantemente su baja sensibilidad

In silico Analysis of the Entire P. glaucum Genome Identifies Regulatory Genes of the bZIP Family Modulated in Response Pathways to Water Stress

The literature reviewed places P. glaucum as a cereal characterized by its nutritional quality and high tolerance to drought stress. However, very little is known about the fine mechanism it uses in response to water stress. To try to clarify this point, we carried out an analysis of the modulation of the expression of regulatory genes of the FT bZIP family. A full genome screening of P. glaucum identified 52 putative FT bZIPs, identifying 9 FT PgbZIP differentially expressed under water stress conditions filtered from RNA-seq data from a Transcriptome deposited at the NCBI. The promoter regions of these genes presented multiple elements or cis ABREs and DRE motifs, thus suggesting their double modulated participation in the slow or adaptive response and in the rapid response of this cereal to water stress. The findings of this study provide complementary data for the understanding of the mechanism behind the adaptation of P. glaucum under water stress, and may be relevant for molecular applications of potential crops.Fil: Garay Farías, Laura Beatriz. Universidad Federal de la Integración Latinoamericana; BrasilFil: Litwiñiuk, Sergio Leandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas; ArgentinaFil: Rojas, Cristian Antonio. Universidad Federal de la Integración Latinoamericana; Brasi

La vigencia de Ferdinand de Saussure en la enseñanza y aprendizaje de lenguas extranjeras.

This article aims at valuing the legacy of De Saussure in the field of foreign language learning and teaching. To avoid digressions, we address only three main issues: the status of Applied Linguistics in the teaching of English, the writing systems in Japanese, and the teaching of Portuguese to Spanish speakers. To contextualize these issues, we describe the socio historical background of the Course in General Linguistics and analyze the dichotomies diachronic/synchronic, signified/signifying, and langue/parole from the perspective of recent semiogenetic and socio semiotic models. The conclusion is that Saussure’s theory proves to be insufficient and restrictive for language learning and teaching, despite the fact that his concept of language underpins both some teaching methods that separate orality from writing and comparative linguistics.Este artículo apunta a valorar el impacto de los planteamientos de Saussure en el campo de la enseñanza y aprendizaje de lenguas extranjeras. Para evitar digresiones abstractas, se opta por tener como referencia tres grandes problemas. El primero dice relación con el estatus de la lingüística aplicada a la enseñanza del inglés, los sistemas de escritura en japonés y la enseñanza de portugués a hispanohablantes. Para situar el abordaje de dichos problemas, se parte por describir el contexto sociohistórico en que surge el Curso de Lingüística Generaly se analizan las dicotomías diacronía/sincronía, significado/significante y lengua/habla a la luz del proceso de semiogénesis y los planteamientos de la sociosemiótica.  Se concluye que el planteamiento de Saussure se constituye en un modelo insuficiente y restringido en el campo de enseñanza y aprendizaje de lenguas, aunque su noción sobre lengua subyace en algunos modelos de enseñanza, en algunas explicaciones sobre la relación entre oralidad y escritura así como en la visión que se tiene sobre lenguas emparentadas