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The commensals on Chilean Decapoda of inland waters are characterized by a marked microendemism. The aim of the present study was to do an exhaustive review on the ectocommensals on Chilean inland-water decapods. The literature revealed the presence of species of Protozoa, viz., eight known only from Parastacus pugnax (Lagenophrys andos, Operculigera insolita, O. parastacis, O. seticola, O. striata, O. taura, Chilenophrys allendei, and Circolagenophrys shiftus), one for both P. pugnax and P. nicoletti (L. anticthos), one for Parastacus pugnax and Samastacus spinifrons (O. asymmetrica), and one reported for Aegla laevis (O. velata). In addition, the presence of flatworms was described, specifically Temnocephala chilensis, associated with A. laevis, P. pugnax, and S. spinifrons, and species of Polychaeta, i.e., Stratiodrilus platensis associated with A. abtao and A. bahamondei, S. aeglaphilus for A. laevis, and S. pugnaxi for P. nicoletti. Biogeographical, ecological and taxonomic implications are discussed.

The distributional patterns of the species of the South American freshwater crayfishes of the family Parastacidae were analysed using panbiogeographical track analyses to identify targeted regions of crayfish biodiversity for understanding biogeographical patterns. Two generalized tracks were identified using the track analysis approach: (1) Uruguay and Brazil (Parastacus brasiliensis, P. brasiliensis promatensis, P. buckupi, P. caeruleodactylus, P. defossus, P. fluviatilis, P. gomesae, P. guapo, P. macanudo, P. pilimanus, P. pilicarpus, P. saffordi, P. tuerkayi, P. varicosus); and (2) Central-southern Chile (P. nicoleti, P. pugnax, Samastacus spinifrons, Virilastacus araucanius, V. jarai, V. retamali and V. rucapihuelensis). These areas were exclusive, with no overlap between them. The results indicate the presence of South American Parastacidae crayfish in Atlantic coastal sub-tropical and Pacific coastal temperate wet climate regions with biogeographic similarities to other South American inland water decapods.

The crayfishes of Chile are endemic species and have been poorly studied with respect to their biology. The available literature is restricted to species descriptions, whereas there is no information about other biological topics such as ectocommensals and parasites, which can affect crayfishes. The aim of the present study was to do a literature review and update the information about ectocommensals and parasites that have been reported from Chilean crayfishes. The literature mentioned the presence of Temnocephala chilensis (Platyhelminthes), Stratiodrilus pugnaxi (Polychaeta) and Protozoa such as species of the genera Operculigera and Lagenophrys as ectocommensals for Parastacus pugnax and Samastacus spinifrons. As an endoparasite, Psorospermium haeckelii was reported, a unicellular eukaryotic organism that was found in P. pugnax ovaria. An additional analysis of collected specimens of P. pugnax and S. spinifrons revealed the presence of T. chilensis, albeit at a low incidence. Ecological, biogeographical and evolutionary topics are discussed considering the case of a marked microendemism of an organism associated with Chilean crayfishes.

The Chilean north Patagonian lakes are characterized by their marked oligotrophic or oligomesotrophic status and low abundance of zooplankton species; many of the lakes with oligomesotrophic status are associated with human intervention due to towns on their shores. The aim of the present study was to determine the relations between spectral properties (LANDSAT OLI), chlorophyll and plankton abundances in two north Patagonian lakes: Villarrica, which has two towns on its shores, and Lake Caburgua, which has native forest on its shores. The results revealed that Lake Villarrica has high reflectance in the near infrared, red and green bands, high concentrations of chlorophyll a, the absence of mixotrophic protozoa, and a high abundance of bacterial and plankton, mainly phytoplankton (Chlophyceae and diatoms) and zooplankton. Lake Caburgua, on the other hand, has low reflectance in the same bands, and low chlorophyll concentrations, low bacterial and zooplankton abundances, with the exception of high mixotrophic ciliates and small phytoplankton, and Volvox colonies. The obtained results agree with limnological observations on both lakes, and observations agrees with similar observations of the spectral properties of glacial north Patagonian lakes and of the zooplankton community, and in this scenario, the use of remote-sensing techniques would be a good tool to predict the plankton community in Patagonian lakes.

Antofagasta Bay is characterized by having a high primary productivity due to the presence of the cold Humboldt Stream. However, due to the current global climate change, also the previously generated biodiversity patterns are changing. The aim of the present study was analysing Antofagasta Bay in order to determine the existence of correlations between optical, i.e., spectral, properties recorded through remote sensing on the one hand, and the presence of dinoflagellates and zooplankton, on the other. The studies were done during two periods, i.e., in February 2019 and February 2020. The results revealed the existence of three main groups of sites: a first group comprising sites sampled in February 2019, with high Band 3 and Band 4 reflectance, high chlorophyl values, and high abundances of Dinophysis and copepods; a second group combining four sites visited in February 2019, with high Gymnodinium and Ceratium, high reflectance in Band 1, Band 2, Band 5, Band 6 and Band 7, and low zooplankton abundance; and finally a third group encompassing all sites sampled in 2020, with high Prorocentrum abundance, and low zooplankton abundance, as well as low reflectance. A similar situation with regard to zooplankton and optical properties was earlier reported for Chilean Patagonian lakes.

Microbial volatile organic compounds may act as semiochemicals, inciting different behavioral responses in insects. Beauveria bassiana is an entomopathogenic fungus, and physiological and environmental factors are positively related to fungal virulence. In this study, we examined the volatile profiles produced by eight B. bassiana strains, isolated from soil plots and mycosed insect cadavers, with different speeds of kill and determined if these compounds induce oviposition behavior in Spodoptera frugiperda. Fungal volatilome analysis revealed differences between the isolates. Isolates from mycosed insects showed higher virulence, larger egg mass area and length, and a higher number of eggs by mass, than those obtained from soil. Furthermore, a dilution of the fungal odoriferous compounds increased the insect response, suggesting that S. frugiperda is highly susceptible to the fungal compound’s fingerprint. Otherwise, the insect response to the natural blend of volatiles released by the fungus was different from that obtained with 3-methylbutanol, which was the most abundant compound in all isolates. The ability of an entomopathogen to produce volatiles that can induce olfactory stimulation of egg-laying behavior could represent an ecological adaptive advantage in which the entomopathogen stimulates the insect population growth.

BACKGROUND Trichoderma spp. are soil fungi that interact with plant roots and associated biota such as other microorganisms and soil fauna. However, information about their interactions with root-feeding insects is limited. Here, interactions between Trichoderma harzianum and the root-feeding insect Phyllophaga vetula, a common insect pest in maize agroecosystems, were examined. RESULTS Applications of T. harzianum and P. vetula to the root system increased and decreased maize growth, respectively. Induced tolerance against herbivore attack was provided by T. harzianum maintaining a robust and functional root system as evidenced by the increased uptake of Cu, Ca, Mg, Na and K. Herbivore tolerance also coincided with changes in the emission of root volatile terpenes known to induce indirect defense responses and attract natural enemies of the herbivore. More importantly, T. harzianum induced de novo emission of several sesquiterpenes such as β-caryophyllene and δ-cadinene. In addition, single and combined applications of T. harzianum and P. vetula altered the sucrose content of the roots. Finally, T. harzianum produced 6-pentyl-2H-pyran-2-one (6-PP) a volatile compound that may act as an antifeedant-signaling compound mitigating root herbivory by P. vetula. CONCLUSION Our results provide novel information about belowground multitrophic plant-microbe-arthropod interactions between T. harzianum and P. vetula in the maize rhizosphere resulting in alterations in maize phenotypic plant responses, inducing root herbivore tolerance.

The Chilean Patagonian lakes are characterized by their marked oligotrophic or oligomesotrophic status and low zooplankton species abundances, many of these lakes with oligomesotrophic status is associated to human intervention due towns in their shores. The aim of the present study was determine the relations between spectral properties (LANDSAT ETM+), chlorophyll and plankton abundances in two north Patagonian lakes, Villarica, that has two towns in its shore, and Caburgua, that has native forest in its shores as basis of environmental pollution monitoring tools. The results revealed that Villarica lake has high reflectances in near infrared, red and green bands, high chlorophyll (a, b and c) concentrations, and high bacterial and plankton abundances, whereas Caburgua lakes has low reflectance in the same bands, and low chlorophyll concentrations, low bacterial and plankton abundances, with exception to high mixotrophic ciliates. The obtained results agree with limnological observations about both lakes, and the comparison with spectral properties agree with similar observations for glacial north Patagonian lakes about spectral properties and zooplankton community.

Plants establish multitrophic interactions above- and belowground with arthropods and microorganisms. Trichoderma spp. are common soil fungi that colonize roots and promote plant growth and health. Under controlled conditions, Trichoderma spp. have been shown to induce plant resistance against the attack of foliar herbivore insects. Here, we investigated the effect of field inoculation with Trichoderma harzianum in the rhizosphere of maize plants during the vegetative plant growth phase on the community of pest and beneficial arthropods associated with maize foliage. Independent of T. harzianum inoculation, the arthropod community was complex and harbored chewing and piercing-sucking herbivores as well as natural enemies. Inoculation with T. harzianum increased the abundance of chewing herbivores, decreased the number of piercing-sucking herbivores and increased the abundance of sampled pest regulating arthropods. In addition, we provide a biochemical basis of shoot metabolites, which may be involved in the alterations of the foliage arthropod community mediated by T. harzianum. Inoculation with T. harzianum caused substantial changes in the levels of sucrose, jasmonic acid (an activator of defense responses against herbivory) and (Z)-3-hexen-1-ol (a volatile compound that attracts natural enemies of herbivores). In conclusion, our results show that inoculation with T. harzianum can alter the arthropod community associated with maize foliage and reduce the abundance of specific pest insects under field conditions.

Antofagasta Bay is characterized by a high primary productivity due to the presence of the cold Humboldt Stream that is associated with a high diversity in flora and fauna in the benthic and pelagial environments of the Chilean west coast. Nevertheless, due to the global climate changes, the existing biodiversity patterns change as well. The aim of the present study was to analyse Antofagasta Bay for determining the existence of patterns between optical properties of the water, and the phytoplankton and zooplankton. The results show that one site had high chlorophyll concentrations, high reflectance, a high abundance of the dinoflagellate genus Dinophysis, and a high abundance of copepodites, whereas five sites had low chlorophyll concentrations, a low reflectance value, low copepodite abundances, and high abundances of dinoflagellates of the genera Ceratium, Gymnodinium and Prorocentrum. These results are similar to earlier observations for the coastal waters along northern Chile.

The automotive industry is undergoing major transformation, with the emergence of vehicular networks, intelligent transportation systems, and autonomous cars over the last decade. These technologies are made possible by recent advances of software, hardware, and communication systems, along with the development of various applications and standards. Today, new technologies are incorporated into cars that detect potential road hazards and improve the driving experience. There are three key components being integrated into cars: sensors, information systems, and communication technologies to create connected vehicle networks. Vehicle-to-vehicle (V2V) communication is being used in connected networks to reduce traffic congestion, improve passengers’ safety, and enable the efficient management of vehicles on roads. Here, we present recent research developments and current trends in V2V communications. We discuss architectural issues and wireless technologies that support V2V. We also present recently proposed security solutions for V2V. Finally, we discuss outstanding challenges for enabling the deployment and adoption of V2V technology.

Lepechinia salviae (Lindl.) Epling is an endemic species from northern Chile, where it is important medicinal plant. Essential oil from the aerial parts of L. salviae was extracted using hy...

This article shows the result of the research carried out during the 2020/21 academic year, in the subject of Information Security, taught in Higher Education, in the fourth year of the Degree in Telematics Engineering in Telecommunications and also in the Degree in Computer Engineering in Information Technology, at the University Center of Merida of the University of Extremadura. The motivation of the research was to monitor the teaching, in a non-invasive way that helps in the teaching / learning process, while the students do not feel that they are being evaluated, minimizing the stress produced by the exams, and trying to automate the learning assessment process so that the teacher has a quick and easy-to-use tool that provides information on the evolution of the students' mental structure, online. The bases of the study that we present are different investigations on pathfinder associative networks and nuclear concepts. The research process developed in several stages. The first step consisted in obtaining the prior knowledge of the students with the help of software created for this purpose. With the data obtained, the associative pathfinder networks of each student were created to know their mental structure. Data were collected at various moments of the teaching course, to verify the evolution of the teaching-learning process and through associative pathfinder networks, the mental structures of the students were graphically represented, being able to observe the evolution of learning during the teaching period.

The study aims to improve our understanding of the full-utilization of immigrant engineers by answering three research questions: (1) what are the economic and social costs of the under-utilization of immigrant engineers, (2) what factors determine immigrant engineers’ employment, and (3) what might be potential solutions to tackle with their under-utilization? We adopt the intersectionality theory to observe a rich set of social factors influential in immigrant engineers’ under-utilization by using 188 surveys and 14 interviews of immigrant engineers living in Australia. The paper concludes with the findings’ theoretical and policy implications, followed by suggestions for future studies.

Fuente TESIUNAM

En este articulo se realiza el analisis mixto de las respuestas dadas por los alumnos sobre la imparticion de un curso realizado en la asignatura de Ingenieria de Software y titulado el Proceso de Software Personal (PSP). Estas respuestas, para su analisis posterior, se han dividido en cuatro grupos atendiendo a cada una de las preguntas realizadas, y para cada una de ellas se han obtenido las categorias de analisis. Estas categorias de analisis nos han permitido agrupar las diferentes respuestas que han dado los alumnos a un cuestionario que posteriormente mostraremos, para comprobar sus experiencias sobre el curso de PSP que han realizado. Las respuestas textuales han sido analizadas mediante el software de analisis cualitativo WebQDA para categorizarlas, poder organizar dichas respuestas y asi, realizar las mejoras oportunas para futuros cursos que se realizaran sobre esta misma disciplina. El resultado final del estudio y analisis cualitativo ha permitido mejorar algunas cuestiones concretas que se realizaban de determinada manera en el curso y que en el futuro permitira cambiar alguna estrategia docente sobre el mismo.

Trichoderma spp. are universal saprotrophic fungi in terrestrial ecosystems, and as rhizosphere inhabitants, they mediate interactions with other soil microorganisms, plants, and arthropods at multiple trophic levels. In the rhizosphere, Trichoderma can reduce the abundance of phytopathogenic microorganisms, which involves the action of potent inhibitory molecules, such as gliovirin and siderophores, whereas endophytic associations between Trichoderma and the seeds and roots of host plants can result in enhanced plant growth and crop productivity, as well as the alleviation of abiotic stress. Such beneficial effects are mediated via the activation of endogenous mechanisms controlled by phytohormones such as auxins and abscisic acid, as well as by alterations in host plant metabolism. During either root colonization or in the absence of physical contact, Trichoderma can trigger early defense responses mediated by Ca2+ and reactive oxygen species, and subsequently stimulate plant immunity by enhancing resistance mechanisms regulated by the phytohormones salicylic acid, jasmonic acid, and ethylene. In addition, Trichoderma release volatile organic compounds and nitrogen or oxygen heterocyclic compounds that serve as signaling molecules, which have effects on plant growth, phytopathogen levels, herbivorous insects, and at the third trophic level, play roles in attracting the natural enemies (predators and parasitoids) of herbivores. In this paper, we review some of the most recent advances in our understanding of the environmental influences of Trichoderma spp., with particular emphasis on their multiple interactions at different trophic levels.

In agroecosystems, herbivore insects damage crops, but in the third trophic level, insects can be parasitized by natural enemies. Trichoderma spp. are common soil and root endophytic fungi that have been widely studied due to their capacity to produce antibiotics, parasitize other fungi and compete with deleterious plant microorganisms. The fall armyworm, Spodoptera frugiperda, is a serious pest of numerous crop plants. In the field, Campoletis sonorensis female wasps parasitize S. frugiperda. Considering these scenarios, it is necessary to look for ecological alternatives for S. frugiperda biocontrol. The aim of this work was to investigate whether Trichoderma atroviride associated with maize roots as part of a multitrophic interaction affects the parasitism rate of C. sonorensis on S. frugiperda. We found that larvae from maize plants whose roots were colonized by T. atroviride were stronger parasitized compared with larvae from non-inoculated plants, indicating that the fungus enhanced the natural mechanism of parasitism. This was correlated with the presence of the low-molecular weight compound 6-pentyl-2H-pyran-2-one (6-PP) released by T. atroviride from the belowground. A pharmacological test showed that 6-PP is an airborne signaling molecule that increased the parasitism rate of C. sonorensis on its enemy. This finding provides new insights into the chemical communication between fungi and insects, and likely represents an inter-kingdom signaling molecule. Furthermore, this study shows a novel role for Trichoderma in multitrophic interactions, and its secondary metabolites in pest control management, presenting an alternative for the biocontrol of S. frugiperda using the combination of T. atroviride and C. sonorensis instead of chemical insecticides.

The construction sector must advance in a more sustainable way and to achieve this goal, the application of global methodologies is needed. These methodologies should take into account all life stages of a building: planning, design, construction, use and demolition. The quantity and variety of the materials used in building construction condition the buildings' environmental and energy impacts. Life Cycle Assessment offers a standardized framework to evaluate the environmental loads of a product, process or activity. This work aims to demonstrate the feasibility of using Life Cycle Assessment (LCA) to select facilities in the construction sector, which minimize environmental and energy impacts. To facilitate the understanding of the proposed methodology, a comparative LCA is performed, to determine the type of thermal insulating material in a double sheet ceramic facade and its thickness, which allows reducing the environmental impacts associated to the enclosure. The three most used enclosure types used in the city of Malaga (Spain) have been selected for this study. The results show the adequacy of the procedure used.

Plant roots naturally associate with Trichoderma spp., which can promote plant health and nutrition. Despite that Trichoderma spp. are well-known biocontrol agents, information on their effects against foliar insect herbivory is limited. Here, we examined the effects of T. atroviride in providing maize (Zea mays) resistance against the insect herbivore Spodoptera frugiperda. Increased plant growth, reduced herbivory and altered insect feeding pattern were observed after maize inoculation with T. atroviride. Plant protection was correlated with increased emission of volatile terpenes and accumulation of jasmonic acid, an activator of defense responses against herbivory. Chemical analyses revealed that T. atroviride produced the volatiles 1-octen-3-ol and 6-pentyl-2H-pyran-2-one. Pharmacological tests showed that both compounds reduced the consumption of foliar tissue and altered the feeding pattern of S. frugiperda in a similar way to T. atroviride. These results provide new insight into the role of T. atroviride in plant health in terms of induction of resistance to insect herbivory and production of antifeedant secondary metabolites.

Resumen La optimización matemática es un concepto matemático esencial para abordar problemas de la vida cotidiana. En el Currículo del Bachillerato español se emplean las herramientas del Análisis Matemático para solucionar los problemas de optimización, siendo aquí donde aparecen las principales dificultades de aprendizaje de la noción. En este trabajo, en primer lugar, se presentan los resultados de un estudio epistemológico de la evolución de la optimización a lo largo de la historia, con el objetivo de fijar los significados de referencia. Posteriormente, se muestra cómo se desarrolla esta noción en tres libros de texto del citado nivel educativo, todo ello con el fin de poder detectar el significado que se pretende abordar en el aula, así como las dificultades potenciales que los alumnos pueden encontrar en torno a este concepto. Abstract Mathematical optimization is an essential concept to manage everyday problems. In the Pre-University Spanish Curriculum, the tools for Mathematical Analysis are used to solve optimization problems. It is exactly in this process where the main teaching difficulties appear. In this article, we present the results of an epistemological study in the evolution of optimization throughout the history of the notion, aiming at fixing the meanings of reference. Then, the notion of optimization is presented in three textbooks, being developed in order to obtain the meaning of this notion in the classroom as well as the potential difficulties the students may find in the concept.

Prevention and treatment of medical device-related infections demands novel strategies for hindering bacteria adhesion and proliferation. The aim of this work was to immobilize gold nanoparticles onto silicone rubber (SR) and then exploit the plasmon resonance properties for the photothermal killing of adhered bacteria. To obtain a good rate of gold deposition, SR films were grafted with PAAc nanobrushes (SR-g-AAc) using a 60Co gamma source. Effects of absorbed dose, monomer concentration, temperature and reaction time on the grafting percentage, swelling and mechanical properties of the films were first investigated. Gold nanoparticles were immobilized on SR and SR-g-AAc following different strategies. Immersion in gold ions (HAuCl4) solution and subsequent reduction made the films to be uniformly coated by 10–20 nm gold nanoparticles as shown by SEM-EDX and XRD. Photothermal features were evidenced as an increase in 6–7 °C in the first 5 min of irradiation with a 514 nm laser at a power density of 0.5 W/cm2. Finally, SR-g-AAc films were challenged against Staphylococcus aureus and effects of irradiation at 514 nm on bacteria survival evaluated. Overall, the gold-immobilized films were shown to be stable against autoclave sterilization and ultrasounds and exhibited outstanding ability to damage adhered bacteria after laser irradiation.

espanolEste trabajo describe una investigacion experimental donde, haciendo uso de la clase inversa, se detectan las deficiencias de los materiales educativos empleados en la docencia universitaria para su mejora. En el proceso educativo los materiales utilizados pasan por diversas etapas hasta ser puestos a disposicion de los alumnos: definicion de los contenidos, seleccion de las fuentes de informacion, procesamiento de los materiales adaptandolos a los contenidos, puesta a disposicion de los estudiantes, estudio de los mismos, comprobacion de defectos de asimilacion y sus motivos, mejora de los materiales y, por ultimo, la comprobacion de que la mejora realizada genera los efectos oportunos. Se realiza un experimento para la deteccion, mejora y comprobacion de esa mejora de algunos materiales educativos. Se utilizan cuestionarios del tipo Just In Time Teaching/Flipped Classroom, para obtener informacion de los alumnos. Y se realiza una investigacion mixta, para la deteccion de los materiales a mejorar y para comprobar los efectos de aplicacion de la misma. EnglishThis paper describes an experimental research where, using the inverse class, the deficiencies of the educational materials used in university teaching are detected for its improvement. In the educational process the materials used go through several stages until they are made available to the students: definition of the contents, selection of information sources, processing of the materials adapting them to the contents, making available to students, study of the same, verification of assimilation defects and their reasons, improvement of the materials and, finally, the verification that the improvement made generates the appropriate effects. An experiment is carried out to detect, improve and verify the improvement of some educational materials. Just In Time Teaching / Flipped Classroom questionnaires are used to obtain student information. And a mixed investigation is carried out, to detect the materials to be improved and to verify the application effects of the same.

Most plant species naturally associate with arbuscular mycorrhizal fungi (AMF), which are known to promote crop nutrition and health in agroecosystems. However, information on how mycorrhizal associations affect plant biotic interactions that occur aboveground with foliar herbivores is limited and needs to be further addressed for the development of pest management strategies. With the objective to examine the influence of maize mycorrhizas on foliar herbivory caused by larvae of Spodoptera frugiperda, a serious pest in maize agroecosystems, we performed a fully factorial greenhouse pot experiment with three factors: Maize genotype (Puma and Milpal H318), AMF (with and without AMF, and without AMF with mineral P) and Insect herbivory (with and without S. frugiperda). Main results showed that inoculation with AMF improved plant growth and foliar P concentration, which coincided with increased foliar damage from herbivory and higher biomass of S. frugiperda larvae. A significant positive correlation between shoot P concentration and larval biomass was also observed. Finally, foliar herbivory by S. frugiperda slightly increased and decreased AMF root colonization in Puma and H318, respectively. In conclusion, our results show that maize plant benefits from AMF in terms of promotion of growth and nutrition, and may also increase the damage caused from insects by improving the food quality of maize leaves for larval growth, which seems to be linked to increased P uptake by the maize mycorrhizal association.