Molecular Marker Technology for Crop Improvement

Since the 1980s, agriculture and plant breeding have changed with the development of molecular marker technology. In recent decades, different types of molecular markers have been used for different purposes: mapping, marker-assisted selection, characterization of genetic resources, etc. These have produced effective genotyping, but the results have been costly and time-consuming, due to the small number of markers that could be tested simultaneously. Recent advances in molecular marker technologies such as the development of high-throughput genotyping platforms, genotyping by sequencing, and the release of the genome sequences of major crop plants open new possibilities for advancing crop improvement. This Special Issue collects sixteen research studies, including the application of molecular markers in eleven crop species, from the generation of linkage maps and diversity studies to the application of marker-assisted selection and genomic prediction.info:eu-repo/semantics/publishedVersio

Photonic Delay Systems as Machine Learning Implementations

Nonlinear photonic delay systems present interesting implementation platforms for machine learning models. They can be extremely fast, offer great degrees of parallelism and potentially consume far less power than digital processors. So far they have been successfully employed for signal processing using the Reservoir Computing paradigm. In this paper we show that their range of applicability can be greatly extended if we use gradient descent with backpropagation through time on a model of the system to optimize the input encoding of such systems. We perform physical experiments that demonstrate that the obtained input encodings work well in reality, and we show that optimized systems perform significantly better than the common Reservoir Computing approach. The results presented here demonstrate that common gradient descent techniques from machine learning may well be applicable on physical neuro-inspired analog computers

Collaborative Development within Open Source Communities

Open source communities are one of the most successful-- and least appreciated--examples of high-performance collaboration and community building on the Internet today. Open source communities began as loosely organized, ad-hoc communities of contributors from all over the world who shared an interest in meeting a common need. However, the organization of these communities has proven to be very flexible and capable of carrying out all kind of developments, ranging from minor projects to huge programs such as Apache (Höhn, & Herr, 2004; Mockus, Fielding, & Herbsleb, 2005

Characterization and Classification of Collaborative Tools

Traditionally, collaboration has been a means for organizations to do their work. However, the context in which they do this work is changing, especially in regards to where the work is done, how the work is organized, who does the work, and with this the characteristics of collaboration. Software development is no exception; it is itself a collaborative effort that is likewise affected by these changes. In the context of both open source software development projects and communities and organizations that develop corporate products, more and more developers need to communicate and liaise with colleagues in geographically distant places about the software product they are conceiving, designing, building, testing, debugging, deploying and maintaining. Thus, work teams face sizeable collaborative challenges, for which they have need of tools that they can use to communicate and coordinate their Work efficiently

Miguel Moya y la revista La América (1879-1882)

En 1879, un año clave dentro de su trayectoria profesional, el periodista, político y empresario Miguel Moya comenzó a escribir en la revista quincenal La América, cabecera doctrinal de las más importantes, longevas y difundidas de todo el siglo XIX español. En ella se ocuparía, durante algo más de dos años, hasta marzo de 1882, de efectuar la crónica de política interior y de actualidad cultural, al mismo tiempo que su maestro y amigo Emilio Castelar llevaba a cabo el comentario de la política exterior. Su lectura resulta hoy de gran interés y amenidad para seguir de cerca la vida pública de nuestro país durante el intervalo que duró su colaboración, y proporcionó a su autor un decisivo espaldarazo intelectual, además de servirle de plataforma de difusión para sus múltiples actividades político-sociales.In 1879, a key year for his career path, the journalist, politician, and entrepreneur Miguel Moya began his contribution at the fortnightly magazine La América, one of the most important, long-lasting, and widely spread publications throughout the entire 19th century. For over two years, until March 1882, he wrote on domestic policy and the contemporary culture scene, while his master and friend Emilio Castelar analyzed foreign policy issues. His interesting articles offer a close follow-up of Spain’s public life during the period of his contribution as a journalist. They also helped to boost his intellectual prestige and became a useful way of promoting his various socio-political initiatives

A consensus map for quality traits in durum wheat based on genome-wide association studies and detection of ortho-meta QTL across cereal species

The present work focused on the identification of durum wheat QTL hotspots from a collection of genome-wide association studies, for quality traits, such as grain protein content and composition, yellow color, fiber, grain microelement content (iron, magnesium, potassium, selenium, sulfur, calcium, cadmium), kernel vitreousness, semolina, and dough quality test. For the first time a total of 10 GWAS studies, comprising 395 marker-trait associations (MTA) on 57 quality traits, with more than 1,500 genotypes from 9 association panels, were used to investigate consensus QTL hotspots representative of a wide durum wheat genetic variation. MTA were found distributed on all the A and B genomes chromosomes with minimum number of MTA observed on chromosome 5B (15) and a maximum of 45 on chromosome 7A, with an average of 28 MTA per chromosome. The MTA were equally distributed on A (48%) and B (52%) genomes and allowed the identification of 94 QTL hotspots. Synteny maps for QTL were also performed in Zea mays, Brachypodium, and Oryza sativa, and candidate gene identification allowed the association of genes involved in biological processes playing a major role in the control of quality traits.info:eu-repo/semantics/publishedVersio

p-probabilistic k-anonymous microaggregation for the anonymization of surveys with uncertain participation

We develop a probabilistic variant of k-anonymous microaggregation which we term p-probabilistic resorting to a statistical model of respondent participation in order to aggregate quasi-identifiers in such a manner that k-anonymity is concordantly enforced with a parametric probabilistic guarantee. Succinctly owing the possibility that some respondents may not finally participate, sufficiently larger cells are created striving to satisfy k-anonymity with probability at least p. The microaggregation function is designed before the respondents submit their confidential data. More precisely, a specification of the function is sent to them which they may verify and apply to their quasi-identifying demographic variables prior to submitting the microaggregated data along with the confidential attributes to an authorized repository. We propose a number of metrics to assess the performance of our probabilistic approach in terms of anonymity and distortion which we proceed to investigate theoretically in depth and empirically with synthetic and standardized data. We stress that in addition to constituting a functional extension of traditional microaggregation, thereby broadening its applicability to the anonymization of statistical databases in a wide variety of contexts, the relaxation of trust assumptions is arguably expected to have a considerable impact on user acceptance and ultimately on data utility through mere availability.Peer ReviewedPostprint (author's final draft

Discovering consensus genomic regions in wheat for root-related traits by QTL meta-analysis

Root system architecture is crucial for wheat adaptation to drought stress, but phenotyping for root traits in breeding programmes is difficult and time-consuming owing to the belowground characteristics of the system. Identifying quantitative trait loci (QTLs) and linked molecular markers and using marker-assisted selection is an efficient way to increase selection efficiency and boost genetic gains in breeding programmes. Hundreds of QTLs have been identified for different root traits in the last few years. In the current study, consensus QTL regions were identified through QTL meta-analysis. First, a consensus map comprising 7352 markers was constructed. For the meta-analysis, 754 QTLs were retrieved from the literature and 634 of them were projected onto the consensus map. Meta-analysis grouped 557 QTLs in 94 consensus QTL regions, or meta-QTLs (MQTLs), and 18 QTLs remained as singletons. The recently published genome sequence of wheat was used to search for gene models within the MQTL peaks. As a result, gene models for 68 of the 94 Root_MQTLs were found, 35 of them related to root architecture and/or drought stress response. This work will facilitate QTL cloning and pyramiding to develop new cultivars with specific root architecture for coping with environmental constraints.info:eu-repo/semantics/publishedVersio