Effects of Fusarium graminearum and Fusarium poae on disease parameters, grain quality and mycotoxin contamination in barley (Part II) Martínez, Mauro; Ramirez Alburquerque, Lady D.; Dinolfo, María Inés; Biganzoli, Fernando; Fernández Pinto, Virginia; Stenglein, Sebastian Alberto Barley is one of the most important winter crops in the world, withmultiple uses such as human consumption, animal feed and for the malting industry. This crop is affected by different diseases, such as Fusarium Head Blight (FHB), that causes losses in yield and quality. In the last years F. graminearum and F. poae were two of the most frequently isolated species in barley grains, so the aim of this study was to evaluate the interaction between these Fusarium species and the effects on disease parameters, grain quality and mycotoxin contamination on five barley genotypes under field conditions.RESULTS: Statistical differences between Fusarium treatments for some parametersdepending mainly on the year/genotype were found. The results showed that germination process was affected by both Fusarium species. As to grain quality and the different hordein fractions, it was observed that F. graminearum affects preferentially D and Chordeins Different concentrations of nivalenol, deoxynivalenol and their acetylated derivatives (3-ADON and 15-ADON) were detected.CONCLUSIONS: In the present work, no evidence of synergism between F.graminearum and F. poae were found regarding disease parameters and mycotoxincontamination. However, at least in the years with favorable climatic conditions to FHB development and depending on the barley genotype, a continuous monitoring is deemed necessary to prevent the negative impact on protein composition and germinative parameters.

A Penicillin Derivative Exerts an Anti-Metastatic Activity in Melanoma Cells Through the Downregulation of Integrin αvβ3 and Wnt/β-Catenin Pathway Barrionuevo, Alejandra Elizabeth; Cayrol, Maria Florencia; Cremaschi, Graciela Alicia; Cornier, Patricia Griselda; Boggian, Dora Bernarda; Delpiccolo, Carina Maria Lujan; Mata, Ernesto Gabino; Roguin, Leonor Patricia; Blank, Viviana Claudia The synthetic triazolylpeptidyl penicillin derivative, named TAP7f, has been previously characterized as an effective antitumor agent in vitro and in vivo against B16-F0 melanoma cells. In this study, we investigated the anti-metastatic potential of this compound on highly metastatic murine B16-F10 and human A375 melanoma cells. We found that TAP7f inhibited cell adhesion, migration and invasion in a dose-dependent manner. Additionally, we demonstrated that TAP7f downregulated integrin αvβ3 expression and Wnt/β-catenin pathway, a signaling cascade commonly related to tumor invasion and metastasis. Thus, TAP7f reduced both the enzymatic activity and the expression levels of matrix-metalloproteinases-2 and -9 in a time dependent manner. Moreover, TAP7f inhibited the expression of the transcription factor Snail and the mesenchymal markers vimentin, and N-cadherin, and up-regulated the expression of the epithelial marker E-cadherin, suggesting that the penicillin derivative affects epithelial–mesenchymal transition. Results obtained in vitro were supported by those obtained in a B16-F10-bearing mice metastatic model, that showed a significant TAP7f inhibition of lung metastasis. These findings suggest the potential of TAP7f as a chemotherapeutic agent for the treatment of metastatic melanoma.

Assessment of high-frequency steady-state visual evoked potentials from below-the-hairline areas for a brain-computer interface based on Depth-of-Field Floriano, Alan; Delisle Rodriguez, Denis; Diez, Pablo Federico; Bastos Filho, Teodiano Freire Background and Objective: Recently, a promising Brain-Computer Interface based on Steady-State Visual Evoked Potential (SSVEP-BCI) was proposed, which composed of two stimuli presented together in the center of the subject's field of view, but at different depth planes (Depth-of-Field setup). Thus, users were easily able to select one of them by shifting their eye focus. However, in that work, EEG signals were collected through electrodes placed on occipital and parietal regions (hair-covered areas), which demanded a long preparation time. Also, that work used low-frequency stimuli, which can produce visual fatigue and increase the risk of photosensitive epileptic seizures. In order to improve the practicality and visual comfort, this work proposes a BCI based on Depth-of-Field using the high-frequency SSVEP response measured from below-the-hairline areas (behind-the-ears). Methods: Two high-frequency stimuli (31 Hz and 32 Hz) were used in a Depth-of-Field setup to study the SSVEP response from behind-the-ears (TP9 and TP10). Multivariate Spectral F-test (MSFT) method was used to verify the elicited response. Afterwards, a BCI was proposed to command a mobile robot in a virtual reality environment. The commands were recognized through Temporally Local Multivariate Synchronization Index (TMSI) method. Results: The data analysis reveal that the focused stimuli elicit distinguishable SSVEP response when measured from hairless areas, in spite of the fact that the non-focused stimulus is also present in the field of view. Also, our BCI shows a satisfactory result, reaching average accuracy of 91.6% and Information Transfer Rate (ITR) of 5.3 bits/min. Conclusion: These findings contribute to the development of more safe and practical BCI.

Acciones didácticas en el desarrollo de un recorrido de estudio y de investigación que involucra a la matemática y a la física en la escuela secundaria.; Didactic Actions in the Development os a Study and Research Path That Involves Mathematics and Physics in Secondary School Gazzola Bascougnet, María Paz; Otero, Maria Rita; Llanos, Viviana Carolina En este trabajo se presentan resultados sobre el desarrollo de un Recorrido de Estudio y de Investigación (REI) que involucra a la Matemática y a la Física, a partir de las acciones o gestos didácticos propuestos por la Teoría Antropológica de lo Didáctico (TAD) como propios de un REI, llamados dialécticas (Chevallard, 2013a). El REI fue implementado en cinco cursos de Matemática en escuelas secundarias con N=116 estudiantes en total. Se emplean técnicas cualitativas de análisis y metaanálisis de datos para construir una categorización inductiva conforme al uso de técnicas cuantitativas de estadística multivariada. Los resultados muestran las dificultades del desarrollo de estos gestos en el aula y permiten interpretar la existencia de un funcionamiento conjunto de ciertas dialécticas, puesto que el aumento de frecuencia de ocurrencia de algunas se corresponde con el aumento de las otras.; This paper presents results on the development of a Study and Research Path (SRP) that involves mathematics and physics, from the didactic actions or gestures proposed by the Anthropological Theory of the Didactic (ATD) as typical of a SRP, called dialectics (Chevallard, 2013a). The SRP was implemented in five secondary school math courses with N=116 students in total. Qualitative techniques for data analysis and meta-analysis are used to construct an inductive categorization according to the use of multivariate quantitative techniques. The results show the difficulties of the development of these gestures in the classroom and allow to interpret the existence of a joint operation of certain dialectics, since the increase in the frequency of occurrence of some corresponds to the increase in the others.

La mégafaune: splendeur et décadence Boivin, Myriam; Pujos, François Roger Francis; Antoine, Pierre Olivier Le gigantisme est l'un des traits les plus inattendus de la faune disparue des néotropiques. Tortues et chinchillas semblent tout autant pris de démesure que le célèbre paresseux géant. Éteints il ny a que quelques milliers d'nnées, ces géants ont côtoyé lhomme

Virulence and pCM1 plasmid carriage are related to BOX-PCR fingerprint type in strains of Clavibacter michiganensis subsp. michiganensis that cause bacterial wilt and canker of tomato in Argentina Wassermann, Eliana; Montecchia, Marcela Susana; Garaventa, Valeria Soledad; Correa, Olga Susana; Romero, Ana María Clavibacter michiganensis subsp. michiganensis (Cmm) causes bacterial wilt and canker in tomato, producing important economic losses worldwide. Its virulence has been related to several putative virulence factors present on a chromosomal pathogenicity island and on plasmids pCM1 and pCM2, in strain NCPPB382. We genotypically characterized a collection of Cmm isolates from the main greenhouse tomato-producing areas of Argentina by BOX-PCR fingerprinting and screened for the presence of genes and plasmids involved in pathogenicity by PCR. In addition, we evaluated in vitro cellulolytic activity and virulence in planta of selected strains. BOX-PCR fingerprinting clustered strains into four groups. Group II was dominant and included the most virulent strains, while Group III was the smallest and had the least virulent strains. All local strains exhibited similar cellulolytic activity. Most of the examined strains carry two plasmids of similar size to those of NCPPB382, although there were strains with one or three plasmids. By PCR amplification of repA, pCM1 was detected only in strains belonging to Group III, which includes local strains closely related to reference strain NCPPB382. All analysed pathogenicity genes were widespread among strains, and so in strains belonging to Groups I and II, celA found on pCM1 in NCPPB382 could be found in the chromosome or in plasmids other than pCM1. This study contributes to a better understanding of the diversity of Cmm genetic profiles and virulence of strains present in Argentina. Such information could be useful for the selection of strains for screening of host resistance and development of resistant tomato varieties.

IMA Commission on New Minerals, Nomenclature and Classification (CNMNC), Newsletter 53: IMA No. 2019-085 Biglia, Marco Esteban; Cooper, Mark A.; Grew, Edward S.; Sfragulla, Jorge Alberto; Márquez Zavalía, María Florencia; Guereschi, Alina Beatriz; Yates, Martin G.; Galliski, Miguel Angel Liraite NaCa2Mn2+ 2 [Fe3+Fe2+]Mn2+ 2 (PO4)6(H2O)2 Ceferino Namuncurá pegmatite, Pocho Department, Córdoba Province, Argentina (31◦370 4500 S, 65◦150 0300 W)

How to explicitly calculate Feynman and Wheeler propagators in the ADS/CFT https://ri.conicet.gov.ar/admin/static/img/broom.pngcorrespondence Plastino, Ángel Luis; Rocca, Mario Carlos We discuss, giving all necessary details, the boundary-bulk propagators. We do it for a scalar field, with and without mass, for both the Feynman and the Wheeler cases. Contrary to standard procedure, we do not need here to appeal to any unfounded conjecture (as done by other authors). Emphasize that we do not try to modify standard ADS/CFT procedures, but use them to evaluate the corresponding Feynman and Wheeler propagators. Our present calculations are original in the sense of being the first ones undertaken explicitly using distributions theory (DT). They are carried out in two instances: 1) when the boundary is a Euclidean space and 2) when it is of Minkowskian nature. In this last case we compute also three propagators: Feynman’s, Anti-Feynman’s, and Wheeler’s (half advanced plus half retarded). For an operator corresponding to a scalar field we explicitly obtain, for the first time ever, the two points’ correlations functions in the three instances above mentioned. To repeat, it is not our intention here to improve on ADS/CFT theory but only to employ it for evaluating the corresponding Wheeler’s propagators.

Toward the detection of permafrost using land-surface temperature mapping Batbaatar, Jigjidsurengiin; Gillespie , Alan R.; Sletten, Ronald S.; Mushkin , Amit; Amit, Rivka; Trombotto, Dario Tomas; Liu , Lu; Petrie, Gregg Permafrost is degrading under current warming conditions, disrupting infrastructure, releasing carbon from soils, and altering seasonal water availability. Therefore, it is important to quantitatively map the change in the extent and depth of permafrost. We used satellite images of land-surface temperature to recognize and map the zero curtain, i.e., the isothermal period of ground temperature during seasonal freeze and thaw, as a precursor for delineating permafrost boundaries from remotely sensed thermal-infrared data. The phase transition of moisture in the ground allows the zero curtain to occur when near-surface soil moisture thaws or freezes, and also when ice-rich permafrost thaws or freezes. We propose that mapping the zero curtain is a precursor to mapping permafrost at shallow depths. We used ASTER and a MODIS-Aqua daily afternoon land-surface temperature (LST) timeseries to recognize the zero curtain at the 1-km scale as a "proof of concept. " Our regional mapping of the zero curtain over an area around the 7000 m high volcano Ojos del Salado in Chile suggests that the zero curtain can be mapped over arid regions of the world. It also indicates that surface heterogeneity, snow cover, and cloud cover can hinder the effectiveness of our approach. To be of practical use in many areas, it may be helpful to reduce the topographic and compositional heterogeneity in order to increase the LST accuracy. The necessary finer spatial resolution to reduce these problems is provided by ASTER (90 m).

Relationship between Formulation, Gelation Kinetics, Micro/Nanostructure and Rheological Properties of Sodium Caseinate Nanoemulsion-Based Acid Gels for Food Applications Montes de Oca Avalos, Juan Manuel; Borroni, Maria Virginia; Huck Iriart, Cristián; Navarro, Alba Sofia del Rosario; Candal, Roberto Jorge; Herrera, Maria Lidia Legislation and concerns about health effects of trans and saturated fatty acids have led to elimination or reduction of them in foods formulation. One of the alternatives for structuring food with healthy ingredients is using food-grade biopolymers such as proteins or polysaccharides to formulate hydrogels. The aim of the present work was to study the relationship among formulation, gelation kinetics, structure, and rheological properties of sodium caseinate (NaCas)/sunflower oil hydrogels prepared from nanoemulsions. NaCas was used as stabilizer in concentrations of 1, 2, 3, or 4 wt.%. Sucrose was also added in 2, 4, 6, or 8 wt.% to the 4-wt.% nanoemulsion. Gelation kinetics was studied by two methods: oscillatory rheometry and Turbiscan. Although gelation time values were significantly different between methods, tendencies were similar: values decreased with increasing protein and sucrose contents. However, the most influential factor on gelation time was the ratio glucono-delta-lactone (GDL)/NaCas. Structure was analyzed by confocal laser scanning microscopy and synchrotron X-ray microtomography. Low-protein content hydrogels (1 or 2 wt.%) had an inhomogeneous structure containing nano- and conventional-size droplets while the 4-wt.% hydrogel kept the initial structural characteristics: homogeneity in dispersed phase distribution and non-aggregated nanodroplets. Sucrose improved structure in terms of homogeneity. Analyses of X-ray microtomoghraphy data showed that while the porosity diminished, the wall width increased with increasing protein and sucrose contents. The hydrogel formulated with 4 wt.% NaCas and 8 wt.% sucrose showed a structure with nanodroplets evenly distributed and the highest G′∞ values of all hydrogels.

Study of the antitumour effects and the modulation of immune response by histamine in breast cancer Nicoud, Melisa Beatriz; Sterle, Helena Andrea; Massari, Noelia Andrea; Táquez Delgado, Mónica Alejandra; Formoso, Karina; Herrero Ducloux, María Verónica; Martinel Lamas, Diego José; Cremaschi, Graciela Alicia; Medina, Vanina Araceli Background: The aim of this work was to improve the knowledge of the role of histamine in breast cancer by assessing the therapeutic efficacy of histamine and histamine H4 receptor (H4R) ligands in a triple-negative breast cancer (TNBC) model developed in immunocompetent hosts. By using publicly available genomic data, we further investigated whether histidine decarboxylase (HDC) could be a potential biomarker. Methods: Tumours of 4T1 TNBC cells were orthotopically established in BALB/c mice. Treatments employed (mg kg−1): histamine (1 and 5), JNJ28610244 (H4R agonist, 1 and 5) and JNJ7777120 (H4R antagonist, 10). Results: Increased HDC gene expression is associated with better relapse-free and overall survival in breast cancer patients. Histamine treatment (5 mg kg−1) of 4T1 tumour-bearing mice reduced tumour growth and increased apoptosis. Although no immunomodulatory effects were observed in wild-type mice, significant correlations between tumour weight and cytotoxic lymphocyte infiltration were detected in H4R knockout mice. H4R agonist or antagonist differentially modulated tumour growth and immunity in 4T1 tumour-bearing mice. Conclusions: Histamine plays a complex role and stands out as a promising drug for TNBC treatment, which deserves to be tested in clinical settings. HDC expression level is associated with clinicopathological characteristics, suggesting a prognostic value in breast cancer.

Analysis of mitochondrial enzymatic activity in blood lymphomonocyte fractions during infection with different Trypanosoma cruzi strains Báez, Alejandra Lidia; Lo Presti, Maria Silvina; Bazán, Paola Carolina; Strauss, Mariana; Velázquez López, Daniela Alejandra; Miler, Noemí del Carmen; Rivarola, Hector Walter; Paglini, Patricia Adriana Proinflammatory and inflammatory mediators induced by Trypanosoma cruzi infection increase the oxidative stress, generating toxicity for cells targeting mitochondria of different tissues. We studied the activity of citrate synthase and complexes I-IV of respiratory chain in mitochondria of blood lymphomonocyte fraction, from albino Swiss mice infected with different isolates of T. cruzi, during Chagas disease evolution. Complexes I-IV were modified in infected groups (p<0.05) in all the stages, and an inflammatory process of different magnitudes was detected in the heart and skeletal muscle according to the isolate. The citrate synthase activity presented modifications in the SGO Z12 and the Tulahuen group (p<0.05). Hearts showed fiber fragmentation and fibrosis; skeletal muscle presented inflammatory infiltrates and in the Tulahuen infected group, there were also amastigote nests. The inflammatory processes produced an oxidative stress that induced different alterations of mitochondrial enzymes activities in the lymphomonocyte fraction that can be detected by a simple blood extraction, suggesting that they could be used as disease markers, especially in the indeterminate phase of Chagas disease.

¿Hacia la regulación postburocrática de los sistemas educativos latinoamericanos?: Un análisis del discurso de los organismos multilaterales de la región en el período 2012-2018; Rumo à regulação pós-burocrática dos sistemas educacionais latino-americanos?: Uma análise do discurso dos organismos multilaterais da região no período 2012-2018; Towards post-bureaucratic regulation of Latin American educational systems?: Analizing the discourse of regional multilateral organizations in the 2012-2018 period Gorostiaga, Jorge Manuel El objetivo de este artículo es analizar de qué manera y en qué medida la retórica de los organismos multilaterales se alinea con la promoción de los modelos de regulación postburocráticos de la educación en el contexto latinoamericano. Enmarcado en la teoría de la regulación y en la noción de campo global de política educativa, este artículo busca contribuir a comprender el componente discursivo de la regulación transnacional. Se analizan documentos auspiciados por tres organismos multilaterales de nivel regional publicados entre 2012 y 2018: la Oficina Regional de Educación para América Latina y el Caribe de la Organización de las Naciones Unidas para la Educación, la Ciencia y la Cultura (OREALC/UNESCO), el Banco Interamericano de Desarrollo (BID) y la Organización de Estados Iberoamericanos para la Educación, la Ciencia y la Cultura (OEI). El foco está puesto en comprender cómo se articula el discurso de estas agencias sobre el gobierno de la educación, así como sus vinculaciones con el contexto de producción y su carácter político, en el sentido de que expresa recomendaciones basadas en valores y no meramente técnicas. Se busca identificar los temas y enfoques dominantes, pero también las contradicciones, las variaciones, diferentes énfasis y planteos alternativos.; O objetivo deste artigo é analisar como e em que medida a retórica das organizações multilaterais se alinha com a promoção de modelos de regulação pós-burocrática da educação no contexto latino-americano. Enquadrado na teoria da regulação e da noção de campo global da política educacional, este artigo pretende contribuir para a compreensão do componente discursivo da regulação transnacional. Analizan-se documentos patrocinados por três agências multilaterais da região publicados entre 2012 e 2018: a Oficina Regional de Educação para a América Latina e o Caribe da Organização das Nações Unidas para a Educação, a Ciência e a Cultura (OREALC/UNESCO), o Banco Interamericano de Desenvolvimento (BID) e a Organização dos Estados Ibero-Americanos para a Educação, a Ciência e a Cultura (OEI). O foco é sobre a compreensão de como se articula o discurso dessas agências sobre o governo da educação, suas ligações com o contexto de produção e seu caráter político, no sentido que expressa recomendações com base em valores e não apenas técnicas. Procura-se identificar os temas e abordagens dominantes, e também as contradições, variações, ênfases diferentes e abordagens alternativas.; The objective of this article is to analyze how and to what extent the rhetoric of multilateral organizations are aligned with the promotion of models of post-bureaucratic regulation of education in the Latin American context. Framed in the theory of regulation and in the notion of a global field of educational policy, this article seeks to contribute to the understanding of the discursive component of transnational regulation. Documents sponsored by three regional multilateral organizations published between 2012 and 2018 are analyzed: the Regional Bureau for Education in Latin America and the Caribbean (OREALC/UNESCO), the Inter-American Development Bank (IDB) and the Organization of Ibero-American States for Education, Science and Culture (OEI). The focus is on understanding how the discourse of these agencies is articulated on the government of education, as well as its links with the production context and its political character, in the sense that it expresses recommendations based on values ​​and not merely techniques. It seeks to identify the dominant themes and approaches, and also the contradictions, variations, different emphases and alternative views.

Understanding atmospheric methane sub-seasonal variability over India Tiwari, Yogesh K.; Guha, Tania; Valsala, Vinu; Saiz López, Alfonso; Cuevas, Carlos; Fernandez, Rafael Pedro; Mahajan, Anoop S. Atmospheric methane (CH4) is considered to be one of the most important greenhouse gases due to its increasing atmospheric concentrations and the fact that it has a warming potential 28 times that of atmospheric carbon dioxide (CO2). Over the Indian sub-continent, fluxes and transport both contribute towards CH4 seasonal variability. Its intra-seasonal variability however is more complex as it is additionally influenced by monsoonal activity during the Asian Summer Monsoon (ASM) period. In this study, the intra-seasonal variability of atmospheric CH4 is examined using ground-based observations at two sites located in the Southern Indian Peninsula, Sinhagad (SNG) and Cape Rama (CRI); and outputs from three different model simulations. Both, the ground based observations and multi-model simulations show that the dominant spectral variability of CH4 is coherent with 20–90 day oscillations in the dynamics of the monsoon (termed hereafter as Intra-Seasonal Oscillations, ISOs). The multi-model analysis revealed that CH4 is heavily influenced by advection due to this intra-seasonal variability. The simulations also display a clear northward propagation of CH4 anomalies over India. The coevolution of CH4, outgoing long wave radiation (to represent convection) and OH radicals (proxy to CH4 sinks) is presented. The study quantifies CH4 variability at intra-seasonal timescales and also its spatial extent. The results suggest that the effect of ISOs on CH4 needs to be considered along with the corresponding observations for future inverse modeling.

EPO and EPO-receptor system as potential actionable mechanism for the protection of brain and heart in refractory epilepsy and SUDEP Auzmendi, Jerónimo Andrés; Puchulu, María Bernardita; Rodríguez, Julio C. G.; Balaszczuk, Ana Maria; Lazarowski, Alberto; Merelli, Amalia The most important activity of erythropoietin (EPO) is the regulation of erythrocyte production by activation of the erythropoietin receptor (EPO-R), which triggers the activation of anti-apoptotic and proliferative responses of erythroid progenitor cells. Additionally, to erythropoietic EPO activity, an antiapoptotic effect has been described in a wide spectrum of tissues. EPO low levels are found in the central nervous system (CNS), while EPO-R is expressed in most CNS cell types. In spite of EPO-R high levels expressed during the hypoxic-ischemic brain, insufficient production of endogenous cerebral EPO could be the cause of determined circuit alterations that lead to the loss of specific neuronal populations. In the heart, high EPO-R expression in cardiac progenitor cells appears to contribute to myocardial regeneration under EPO stimulation. Several lines of evidence have linked EPO to an antiapoptotic role in CNS and in heart tissue. In this review, an antiapoptotic role of EPO/EPO-R system in both brain and heart under hypoxic conditions, such as epilepsy and sudden death (SUDEP) has been resumed. Additionally, their protective effects could be a new field of research and a novel therapeutic strategy for the early treatment of these conditions and avoid SUDEP.

Mechanism of long-term capillary water uptake in cementitious materials Alderete, N. M.; Villagrán Zaccardi, Yury Andrés; de Belie, Nele Capillary imbibition or water uptake tests are practical and they satisfactorily describe the performance of cementitious materials. Most of these tests are performed for a short period (<1 week), however, additional water uptake has been documented after the water front has covered the total height of samples. This process occurs at a very low rate and it could provide further information about the pore structure. We investigated long-term capillary imbibition in mortar and concrete with and without supplementary cementitious materials. This paper reports our results and results from literature, and proposes a phenomenological description of the process. The trends observed from long-term tests are consistent across different water to cementitious material ratios, binder types, fine and coarse aggregates, curing ages, and conditioning regimes. Long-term measurements reveal primary and secondary periods of capillary imbibition that are well described by a bi-linear relationship with the fourth root of time.

Synthesis of Fe2SiO4-Fe7Co3 nanocomposite dispersed in the mesoporous SBA-15: Application as magnetically separable adsorbent Da Silva, Monickarla Teixeira Pegado; Barbosa, Felipe Fernandes; Morales Torre, Marco Antonio; Villarroel Rocha, Jhonny; Sapag, Manuel Karim; Pergher, Sibele; Braga, Tiago Pinheiro The mixture containing alloy and oxide with iron-based phases has shown interesting properties compared to the isolated species and the synergy between the phases has shown positive effect on dye adsorption. This paper describes the synthesis of Fe2SiO4-Fe7Co3-based nanocomposite dispersed in Santa Barbara Amorphous (SBA)-15 and its application in dye adsorption followed by magnetic separation. Thus, it was studied the variation of reduction temperature and amount of hydrogen used in synthesis and the effect of these parameters on the physicochemical properties of the iron and cobalt based oxide/alloy mixture, as well as the methylene blue adsorption capacity. The XRD and Mössbauer results, along with the temperature-programmed reduction (TPR) profiles, confirmed the formation of Fe2SiO4-Fe7Co3-based nanocomposites. Low-angle XRD, N2 isotherms, and TEM images show the formation of the SBA-15 based mesoporous support with a high surface area (640 m2/g). Adsorption tests confirmed that the material reduced at 700 ◦C using 2% of H2 presented the highest adsorption capacity (49 mg/g). The nanocomposites can be easily separated from the dispersion by applying an external magnetic field. The interaction between the dye and the nanocomposite occurs mainly by π-π interactions and the mixture of the Fe2SiO4 and Fe7Co3 leads to a synergistic effect, which favor the adsorption.

Utilización de lana de oveja de bajo valor de mercado como aislante térmico en la Patagonia Zanovello, Lucas; Cardoso, María Betina El presente trabajo se realizó con el objetivo de analizar alternativas para la obtención de aislantes térmicos para las viviendas de la región sur de Río Negro, a partir de un recurso disponible como la lana de oveja. Para ello, se desarrollaron herramientas manuales y ayudas mecánicas para luego analizar comparativamente las diferentes técnicas de elaboración de paños. Se tuvo en cuenta también el método multicriterio NAIADE tomando como eje principal la adecuación de la tecnología propuesta al contexto de uso. Se analizó el comportamiento térmico de los paños obtenidos mediante medición de transmisión de calor, en régimen estacionario utilizando un equipamiento de autoconstrucción. Como resultado de este análisis se seleccionaron las técnicas de elaboración de aislantes a partir de lana de oveja trabajadas en seco. Las mediciones de conductividad térmica fueron contrastadas con los ensayos realizados por INTI Construcciones, bajo la norma ISO 8301:2010, obteniendo como resultados aislantes con una conductividad térmica cercanas a 0,038 W/m2 Kº. Este resultado demuestra que estos aislantes resultan eficientes y adecuados para la rehabilitación higrotérmica de las viviendas rurales de la región Patagonia.

Searching potential candidates for development of protective cultures: Evaluation of two Lactobacillus strains to reduce Listeria monocytogenes in artificially contaminated milk García, María José; Ruíz, Francesca; Asurmendi, Paula; Pascual, Liliana; Barberis, Isabel Lucila The aims of this work were (a) to select the minimum concentrations of two bacteriocin-producing lactobacilli strains to reduce Listeria monocytogenes growth in whole milk, (b) to evaluate the individual and combined application of these chosen lactobacilli concentrations as protective culture in this food and, (c) to estimate if lactobacilli growth caused undesirable changes in the visible characteristics of milk. The selected minimum lactobacilli concentration with antilisterial activity was 106 CFU ml−1 for both lactobacilli. Although a high initial concentration of L. monocytogenes (104 CFU ml−1) was added to milk, a notable reduction on listerial counts (2–4 log CFU ml−1) was achieved in comparison to the control. These lactobacilli showed a good adaptability in milk reaching optimal counts and not causing undesirable visible changes. In conclusion, the use of these lactobacilli could be considered as a bio-strategy potentially effective to limit the contamination by L. monocytogenes in certain milk-derived products.

Switching of dominant positions between two sand‐fixing shrub species during the dune revegetation process is underlain by their contrasting xylem hydraulics and water‐use strategies Guo, Jing‐Jing; Gong, Xue-Wei; Fang, Li-Dong; Jiang, De-Ming; Ala, Musa; Bucci, Sandra Janet; Scholz, Fabian Gustavo; Goldstein, Guillermo; Hao, Guang-You Differences in key physiological characteristics between plant species can result in their contrasting performances in vegetation restoration projects, but ecophysiological comparative studies in close relation to ecological restoration projects are scarce. Hedysarum fruticosum Pall. and Caragana microphylla Lam. are two leguminous shrub species widely used in combination for fixation of active sand dunes in semiarid regions of northern China, but they clearly differ in fitness at different stages of dune vegetation development; that is, H. fruticosum quickly gains a community dominance at the initial stage but yields to C. microphylla in a few years after the fixation of dunes. To reveal the underlying mechanism of such a pattern, key physiological characteristics related to xylem water transport, leaf water use, and drought tolerance were compared between these two species at a typical site of sand dune fixation project in Inner Mongolia. Compared with C. microphylla , H. fruticosum shows an acquisitive and risky water management strategy with substantially higher hydraulic efficiency and photosynthetic capability but reduced resistance to drought‐induced xylem embolism, which endows it an advantage under conditions of relatively high soil water availability at the early stage of dune fixation. In contrast, C. microphylla exhibits more conservative water use and characteristics of greater drought tolerance, which results in greater dominance under the more drought‐stressed conditions of the later stage of dune fixation. Our study for the first time provides a potential mechanistic explanation for the clear switching of dominant positions between the two important sand‐fixing shrub species during the sand dune revegetation process.