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The Chilean eduaction system faces a huge challenge in reducing student achievement inequalities related to socioeconomic differences. This study explores those inequialities relationship to teacher quality distribution. It is the first study analyzing these relationships using value-added models based on Chilean census databases. This study also uses a more comprehensive definition of teache quality than is common in the current literature by including indicators for teachers pedagogical practices and for their content knowledge at the school level. The results suggest that these characteristics are strongly related to the students level of achievement and their achievement gains between assessments. The results additionally confirm that students socioeconomic status (SES) also explains a sizable portion of the level and the difference in achievement over time. Lower SES students, therefore, are at a disadvantage not only due to initial lower achievement levels but also to lower improvement rates over time. Even though the results should be taken with caution, they suggest that improvements in teacher quality, paying particular attention to improvements focused on schools with a higher concentration of poverty, could offset part of the social inequalities and, therefore, reduce learning disparities. The current distribution of teachers, however, does not seem to be reducing these inequalities. To reduce them, teacher quality at lower SES schools needs to be higher than in schools serving higher SES students. If the Chilean government aims to reduce these learning differences, it should consider policies to attract, develop, and retain better teachers in the schools attended by the poorest students.

Cybercrime is a major concern for corporations, business owners, governments and citizens, and it continues to grow in spite of increasing investments in security and fraud prevention. The main challenges in this research field are: being able to detect unknown attacks, and reducing the false positive ratio. The aim of this research work was to target both problems by leveraging four artificial intelligence techniques. The first technique is a novel unsupervised learning method based on skip-gram modeling. It was designed, developed and tested against a public dataset with popular intrusion patterns. A high accuracy and a low false positive rate were achieved without prior knowledge of attack patterns. The second technique is a novel unsupervised learning method based on topic modeling. It was applied to three related domains (network attacks, payments fraud, IoT malware traffic). A high accuracy was achieved in the three scenarios, even though the malicious activity significantly differs from one domain to the other. The third technique is a novel unsupervised learning method based on deep autoencoders, with feature selection performed by a supervised method, random forest. Obtained results showed that this technique can outperform other similar techniques. The fourth technique is based on an MLP neural network, and is applied to alert reduction in fraud prevention. This method automates manual reviews previously done by human experts, without significantly impacting accuracy.

Climate change (CC) is probably the strongest politically charged scientific matter of this century and the aim of this research is to detail some guidelines about how is the information regarding to this topic when it comes from a politician source and to determine, among other matters, which parties do the politicians who appear as sources belong. The research is carried out analyzing all online edition news published of two of the main spanish newspapers, 'El País' and 'ABC', during 2017. A statistical methodology has been used in order to identify significant differences between both newspapers and variables of interest, using contingency tables and Chi-square test. The conclusions show that most of the politicians who appear as information sources in information about CC are foreigners and not spanish, as well as politicians are rarely involved in pedagogy related about climatic issues. ; El cambio climático (CC) es probablemente el tema científico más fuertemente politizado del siglo y el objetivo de esta investigación es detallar pautas sobre cómo son las informaciones que aparecen sobre este tema cuando la fuente es un político y determinar, entre otras cuestiones, a qué partidos pertenecen los políticos que aparecen como fuentes. La investigación parte del análisis de todas las noticias aparecidas en las ediciones digitales de dos de los principales diarios españoles, El País y ABC, durante el año 2017. Se ha recurrido a una metodología estadística a la hora de identificar diferencias significativas entre los dos diarios analizados y las variables de interés, utilizando tablas de contingencia con pruebas de chi-cuadrado. Las conclusiones permiten avanzar que la mayoría de los políticos que aparecen como fuentes en informaciones sobre CC son extranjeros y no españoles, así como que los políticos hacen muy poca pedagogía sobre cuestiones climáticas.

Large bilingual parallel texts (also known as bitexts) are usually stored in a compressed form, and previous work has shown that they can be more efficiently compressed if the fact that the two texts are mutual translations is exploited. For example, a bitext can be seen as a sequence of biwords —pairs of parallel words with a high probability of co-occurrence— that can be used as an intermediate representation in the compression process. However, the simple biword approach described in the literature can only exploit one-to-one word alignments and cannot tackle the reordering of words. We therefore introduce a generalization of biwords which can describe multi-word expressions and reorderings. We also describe some methods for the binary compression of generalized biword sequences, and compare their performance when different schemes are applied to the extraction of the biword sequence. In addition, we show that this generalization of biwords allows for the implementation of an efficient algorithm to look on the compressed bitext for words or text segments in one of the texts and retrieve their counterpart translations in the other text —an application usually referred to as translation spotting— with only some minor modifications in the compression algorithm. ; This work has been supported by the Spanish Government through projects TIN2009-14009-C02-01 and TIN2009-14009-C02-02, and by the Millennium Institute for Cell Dynamics and Biotechnology (grant ICM P05-001-F).

19 páginas, 4 figuras, 2 tablas ; Global warming will inevitably affect crop development and productivity, increasing uncertainty regarding food production. The exploitation of genotypic variability can be a promising approach for selecting improved crop varieties that can counteract the adverse effects of future climate change. We investigated the natural variation in yield performance under combined elevated CO2 and high-temperature conditions in a set of 60 bread wheat genotypes (59 of the 8TH HTWSN CIMMYT collection and Gazul). Plant height, biomass production, yield components and phenological traits were assessed. Large variations in the selected traits were observed across genotypes. The CIMMYT genotypes showed higher biomass and grain yield when compared to Gazul, indicating that the former performed better than the latter under the studied environmental conditions. Principal component and hierarchical clustering analyses revealed that the 60 wheat genotypes employed different strategies to achieve final grain yield, highlighting that the genotypes that can preferentially increase grain and ear numbers per plant will display better yield responses under combined elevated levels of CO2 and temperature. This study demonstrates the success of the breeding programs under warmer temperatures and the plants' capacity to respond to the concurrence of certain environmental factors, opening new opportunities for the selection of widely adapted climate-resilient wheat genotypes. ; This research was supported by the Spanish National R&D&I Plan of the Ministry of Economy and Competitiveness (Projects AGL2013-41363-R and AGL2016-79589-R) and Ministry of Science and Innovation (Project PID2019-107154RB-100), as well as the regional government, the Junta de Castilla y León (Projects CSI083U16 and CSI260P20), with European Regional Development Fund, ERDF. Project "CLU-2019-05—IRNASA/CSIC Unit of Excellence", funded by the Junta de Castilla y León and co-financed by the European Union (ERDF "Europe drives our growth"). E.L. Marcos-Barbero was the recipient of a pre-doctoral contract from the Junta de Castilla y León (E-37-2017-0066125) ; Peer reviewed

43 páginas, 4 figuras, 4 tablas. -- The definitive version is available at http://www.elsevier.com ; Variations induced by mutagenesis may identify targets for adapting to rising atmospheric CO2 concentrations. G132 is a barley mutant with strong decreases in photosynthesis, Rubisco and carbohydrate content, but increased Rubisco transcripts. We tested the hypothesis that G132 will record a greater stimulation of photosynthesis and dry mass gain than the wild-type (WT) in response to CO2 enrichment. A growth chamber experiment compared the mutant G132 and the WT developed in ambient (~390 µmol mol-1) and elevated (1200 µmol mol-1) CO2. Photosynthesis, protein and carbohydrate contents, Rubisco and nitrate reductase activities, leaf morphology, plant dry matter and leaf area were determined. The transcriptome responses of fully expanded leaves of G132 and WT to elevated CO2 were investigated using microarrays and qRT-PCR. Growth in elevated CO2 stimulated photosynthesis more in G132 than in WT, in association with a lack of Rubisco down-regulation and lower carbohydrate levels in G132. Electron transport-related proteins increased in G132 and decreased in WT. Elevated CO2 induced more changes in gene expression in WT than G132. Clustering of the corresponding transcripts showed that the expression of genes involved in carbohydrate synthesis and nitrogen assimilation was enhanced, while that for stress-related genes was repressed in both genotypes, and gene expression for jasmonate metabolism was activated in G132. Elevated CO2 decreased the transcript levels for a greater number of transcription factors in WT than in G132. CO2 enrichment increased leaf area in G132 but not in WT, and induced greater dry mass increases in the mutant. The low Rubisco and carbohydrate content and enhanced Rubisco transcripts recorded in G132 are traits that may improve adaptation to rising CO2. ; This work was funded by the Spanish Research and Development Programme-European Regional Development Fund, ERDF [Project RTA2009-00006-C04-01] and the regional government, the Junta de Castilla y León [Projects CSI148A11-2 and CSI250U13]. ; Peer reviewed

46 páginas, 3 figuras, 6 tablas, 3 tablas suplementarias, 2 figuras suplementarias. -- The definitive version is available at http://www.elsevier.com ; Chemical mutagenesis induces variations that may assist in the identification of targets for adaptation to growth under atmospheric CO2 enrichment. The aim of this work was to characterize the limitations causing reduced photosynthetic capacity in G132 mutagenized barley (Hordeum vulgare L. cv. Graphic) grown in a glasshouse. Compared to the wild type (WT) G132 showed increased transcript levels for the PSII light harvesting complex, but lower levels of chlorophyll, transcripts for protochlorophyllide oxidoreductase A and psbQ, and PSII quantum efficiency in young leaves. Rubisco limitation had an overriding influence on G132 photosynthesis, and was due to strong and selective decreases in Rubisco protein and activity. These reductions were accompanied by enhanced Rubisco transcripts, but increased levels of a Rubisco degradation product. G132 showed lower levels of carbohydrates, amino acids and corresponding transcripts, and proteins, but not of nitrate. Many of the measured parameters recovered in the mutant as development progressed, or decreased less than in the WT, indicating that senescence was delayed. G132 had a longer growth period than the WT and similar final plant dry matter. The reduced resource investment in Rubisco of G132 may prove useful for studies on barley adaptation to elevated CO2 and climate change. ; This work was funded by the Spanish Research and Development Programme-European Regional Development Fund, ERDF (Project RTA2009-00006-C04-01) and the regional government, the Junta de Castilla y León (Projects CSI148A11-2 and CSI250U13). ; Peer reviewed

23 páginas, 6 tablas, 3 figuras ; The progressive rise in atmospheric CO2 concentrations and temperature associated with climate change is predicted to have a major impact on the productivity and quality of food crops. Therefore, food security is highly dependent on climate change. Following a survey with 60 bread wheat genotypes, here we investigated the genetic variation in grain yield and nutritional quality among 10 of these genotypes grown under elevated CO2 and temperature. With this purpose, the biomass production, grain yield-related traits, the grain concentration of starch, total protein, phenolic compounds, and mineral nutrients, together with the total antioxidant capacity, were determined. Variation among genotypes was found for almost all the studied traits. Higher grain and ear numbers were associated with increased grain yield but decreased grain total protein concentration and minerals such as Cu, Fe, Mg, Na, P, and Zn. Mineral nutrients were mainly associated with wheat biomass, whereas protein concentration was affected by plant biomass and yield-related traits. Associations among different nutrients and promising nutrient concentrations in some wheat genotypes were also found. This study demonstrates that the exploration of genetic diversity is a powerful approach, not only for selecting genotypes with improved quality, but also for dissecting the effect of the environment on grain yield and nutritional composition ; This research was supported by the Spanish National R&D&I Plan of the Ministry of Economy and Competitiveness (Projects AGL2013-41363-R and AGL2016-79589-R) and the regional government, the Junta de Castilla y León (Projects CSI083U16 and CSI260P20), with European Regional Development Fund, ERDF. E.L. Marcos-Barbero was the recipient of a pre-doctoral contract from the Junta de Castilla y León (E-37-2017-0066125). ; Peer reviewed

33 páginas, 3 tablas, 6 figuras. -- The definitive version is available at http://www.elservier.com ; The mechanisms of stomatal sensitivity to CO2 are yet to be fully understood. The role of photosynthetic and non-photosynthetic factors in stomatal responses to CO2 was investigated in wild-type barley (Hordeum vulgare var. Graphic) and in a mutant (G132) with decreased photochemical and Rubisco capacities. The CO2 and DCMU responses of stomatal conductance (gs), gas exchange, chlorophyll fluorescence and levels of ATP, with a putative transcript for stomatal opening were analysed. G132 had greater gs than the wild-type, despite lower photosynthesis rates and higher intercellular CO2 concentrations (Ci). The mutant had Rubisco-limited photosynthesis at very high CO2 levels, and higher ATP contents than the wild-type. Stomatal sensitivity to CO2 under red light was lower in G132 than in the wild-type, both in photosynthesizing and DCMU-inhibited leaves. Under constant Ci and red light, stomatal sensitivity to DCMU inhibition was higher in G132. The levels of a SLAH3-like slow anion channel transcript, involved in stomatal closure, decreased sharply in G132. The results suggest that stomatal responses to CO2 depend partly on the balance of photosynthetic electron transport to carbon assimilation capacities, but are partially regulated by the CO2 signalling network. High gs can improve the adaptation to climate change in wellwatered conditions. ; This work was funded by the Spanish Research and Development Programme-European Regional Development Fund, ERDF (Projects RTA2009-00006-C04-01 and AGL2009-11987) and the regional government, the Junta de Castilla y León (Projects CSI148A11-2 and CSI250U13). ; Peer reviewed

The mechanisms of stomatal sensitivity to CO2 are yet to be fully understood. The role of photosynthetic and non-photosynthetic factors in stomatal responses to CO2 was investigated in wild-type barley (Hordeum vulgare var. Graphic) and in a mutant (G132) with decreased photochemical and Rubisco capacities. The CO2 and DCMU responses of stomatal conductance (gs), gas exchange, chlorophyll fluorescence and levels of ATP, with a putative transcript for stomatal opening were analysed. G132 had greater gs than the wild-type, despite lower photosynthesis rates and higher intercellular CO2 concentrations (Ci). The mutant had Rubisco-limited photosynthesis at very high CO2 levels, and higher ATP contents than the wild-type. Stomatal sensitivity to CO2 under red light was lower in G132 than in the wild-type, both in photosynthesizing and DCMU-inhibited leaves. Under constant Ci and red light, stomatal sensitivity to DCMU inhibition was higher in G132. The levels of a SLAH3-like slow anion channel transcript, involved in stomatal closure, decreased sharply in G132. The results suggest that stomatal responses to CO2 depend partly on the balance of photosynthetic electron transport to carbon assimilation capacities, but are partially regulated by the CO2 signalling network. High gs can improve the adaptation to climate change in wellwatered conditions. ; This work was funded by the Spanish Research and Development Programme-European Regional Development Fund, ERDF (Projects RTA2009-00006-C04-01 and AGL2009-11987) and the regional government, the Junta de Castilla y León (Projects CSI148A11-2 and CSI250U13). J. Córdoba was the recipient of a pre-doctoral contract from the National Institute of Agricultural and Food Research-INIA.

Protein phosphorylation and membrane proteins play an important role in the infection of plants by phytopathogenic fungi, given their involvement in signal transduction cascades. Botrytis cinerea is a well-studied necrotrophic fungus taken as a model organism in fungal plant pathology, given its broad host range and adverse economic impact. To elucidate relevant events during infection, several proteomics analyses have been performed in B. cinerea, but they cover only 10% of the total proteins predicted in the genome database of this fungus. To increase coverage, we analysed by LC-MS/MS the first-reported overlapped proteome in phytopathogenic fungi, the "phosphomembranome" of B. cinerea, combining the two most important signal transduction subproteomes. Of the 1112 membrane-associated phosphoproteins identified, 64 and 243 were classified as exclusively identified or overexpressed under glucose and deproteinized tomato cell wall conditions, respectively. Seven proteins were found under both conditions, but these presented a specific phosphorylation pattern, so they were considered as exclusively identified or overexpressed proteins. From bioinformatics analysis, those differences in the membrane-associated phosphoproteins composition were associated with various processes, including pyruvate metabolism, unfolded protein response, oxidative stress response, autophagy and cell death. Our results suggest these proteins play a significant role in the B. cinerea pathogenic cycle. ; This research has been financed by the Spanish Government under project AGL2015-65684-C2-2-R supported by the Spanish Ministry of Economy and Competitiveness. Eva Liñeiro was supported by an FPI grant from the University of Cádiz (2010-152). The CRG/UPF Proteomics Unit is a member of the ProteoRed PRB3 consortium which is supported by grant PT17/0019 of the PE I+D+i 2013–2016 from the Instituto de Salud Carlos III (ISCIII) and ERDF. We acknowledge support from the Spanish Ministry of Economy and Competitiveness, "Centro de Excelencia Severo Ochoa 2013–2017", SEV-2012-0208, and "Secretaria d'Universitats i Recerca del Departament d'Economia i Coneixement de la Generalitat de Catalunya" (2017SGR595).