The Meaning of Syntactic Dependencies

This paper discusses the semantic content of syntactic dependencies. We assume that syntactic dependencies play a central role in the process of semantic interpretation. They are defined as selective functions on word denotations. Among their properties, special attention will be paid to their ability to make interpretation co-compositional and incremental. To describe the semantic properties of dependencies, the paper will be focused on two particular linguistic tasks: word sense disambiguation and attachment resolution. The second task will be performed using a strategy based on automatic acquisition from corpora

Propuesta para una semántica de las dependencias sintácticas

El principal objetivo de este artículo es proponer un modelo formal del proceso de interpretación semántica de las dependencias sintácticas. Definiremos una dependencia sintáctica como una operación binaria que toma como argumentos las denotaciones de dos palabras relacionadas (núcleo y modificador), y devuelve una reordenación de sus denotaciones. Asumimos que esta operación binaria desempeña un papel esencial en el proceso de interpretación semántica

Using the Outlier Detection Task to Evaluate Distributional Semantic Models

In this article, we define the outlier detection task and use it to compare neural-based word embeddings with transparent count-based distributional representations. Using the English Wikipedia as a text source to train the models, we observed that embeddings outperform count-based representations when their contexts are made up of bag-of-words. However, there are no sharp differences between the two models if the word contexts are defined as syntactic dependencies. In general, syntax-based models tend to perform better than those based on bag-of-words for this specific task. Similar experiments were carried out for Portuguese with similar results. The test datasets we have created for the outlier detection task in English and Portuguese are freely availableThis work was supported by a 2016 BBVA Foundation Grant for Researchers and Cultural Creators and by Project TELEPARES, Ministry of Economy and Competitiveness (FFI2014-51978-C2-1-R). It has received financial support from the Consellería de Cultura, Educación e Ordenación Universitaria (accreditation 2016–2019, ED431G/08) and the European Regional Development Fund (ERDF)S

Compositional Distributional Semantics with Syntactic Dependencies and Selectional Preferences

This article describes a compositional model based on syntactic dependencies which has been designed to build contextualized word vectors, by following linguistic principles related to the concept of selectional preferences. The compositional strategy proposed in the current work has been evaluated on a syntactically controlled and multilingual dataset, and compared with Transformer BERT-like models, such as Sentence BERT, the state-of-the-art in sentence similarity. For this purpose, we created two new test datasets for Portuguese and Spanish on the basis of that defined for the English language, containing expressions with noun-verb-noun transitive constructions. The results we have obtained show that the linguistic-based compositional approach turns out to be competitive with Transformer modelsThis work has received financial support from DOMINO project (PGC2018-102041-B-I00, MCIU/AEI/FEDER, UE), eRisk project (RTI2018-093336-B-C21), the Consellería de Cultura, Educación e Ordenación Universitaria (accreditation 2016-2019, ED431G/08, Groups of Reference: ED431C 2020/21, and ERDF 2014-2020: Call ED431G 2019/04) and the European Regional Development Fund (ERDF)S

Transcriptomics in pulmonary arterial hypertension - diagnostics and pathobiology

Pulmonary arterial hypertension (PAH) is a rare disease characterised by remodelling of the pulmonary vasculature and subsequent increase in vascular resistance, leading to right ventricle overexertion and eventual heart failure. Responses to treatment and disease progression vastly differ between PAH patients, while standard clinical phenotypes are not sufficient for accurate patient stratification. Molecular profiling through multi-omic approaches offers greater granularity for PAH patient characterisation and could improve initial risk stratification, treatment selection and monitoring, as well as providing insights into new biological pathways not yet targeted by current therapies. Transcriptomic approaches, such as RNA-sequencing (RNAseq), permit comprehensive analyses of gene expression in tissue samples. Whole blood RNA analysis offers an alternative “liquid biopsy” to lung biopsy—which carries a high risk in PAH—and can be performed sequentially. Previous PAH whole blood transcriptomic studies have been limited by cohort numbers and methodologies used—such as the less sensitive and probe-dependent microarrays—, especially when compared with the comprehensive nature of RNAseq. RNAseq followed by differential expression analysis were utilised to identify PAH-associated transcriptomic profiles in a cohort of 359 PAH patients and 72 age- and sex-matched healthy controls. A LASSO RNA diagnostic model of 25 differentially expressed genes best distinguishing between PAH patients and healthy controls derived from whole blood PAH RNA signature could effectively separate PAH patients in an independent group. RNA model scores were associated with disease severity (p= 0.008) and survival (p= 4.66x10-6) in patients. These results were validated externally in two different cohorts (including 58 and 156 PAH patients and 25 and 110 healthy controls respectively), which highlighted the potential role in PAH of adenosylmethionine decarboxylase 1 (AMD1) and polyamines. Mendelian randomisation analysis implicated SMAD5 in PAH pathogenesis (p= 0.028). A combined diagnostic model of 25 RNAs and 7 metabolites was developed which performed better at distinguishing PAH patients from healthy controls than the 7-metabolite model alone (p= 0.002). A second analysis more sensitive to the specific characteristics of PAH was also conducted. A cohort of 147 PH patients and 45 disease controls was utilised to identify gene expression differences between PAH, other forms of PH and other symptomatic cardiovascular non-PH patients (“disease controls”). LASSO diagnostic models were developed from RNA profiles, and they were able to distinguish between disease controls and both PAH (p= 0.049) and all PH (p= 1.92x10-5) patients, but not between PAH and other PH (p= 0.719). Comparison of RNA profiles highlighted the potential role of SEC22B, ZNF254, PPA2, CAMKMT, FER and EDEM1 in PAH pathology. An in-silico analysis for compound repurposing, the Connectivity Map (CMap) database, was utilised to predict small molecule compounds which reverse the identified whole blood PAH RNA signature. The protein synthesis inhibitor Homoharringtonine—approved for leukaemia treatment and one of the top six compounds identified by CMap—, was shown to effectively reverse PAH transcriptional changes in isolated PBMCs and hPAECs and induce positive functional changes in hPAECs in vitro. These results emphasise the potential of transcriptomics—and general omics—for PAH research. PAH RNA profiles were identified that associated with disease progression and mortality and several transcripts were implicated in PAH pathology. RNA profiles separating PH patients from other symptomatic patients were also identified. Homoharringtonine showed therapeutic potential in in vitro assays using PBMCs and hPAECs and should be investigated further.Open Acces

The role of syntactic dependencies in compositional distributional semantics

This article provides a preliminary semantic framework for Dependency Grammar in which lexical words are semantically defined as contextual distributions (sets of contexts) while syntactic dependencies are compositional operations on word distributions. More precisely, any syntactic dependency uses the contextual distribution of the dependent word to restrict the distribution of the head, and makes use of the contextual distribution of the head to restrict that of the dependent word. The interpretation of composite expressions and sentences, which are analyzed as a tree of binary dependencies, is performed by restricting the contexts of words dependency by dependency in a left-to-right incremental way. Consequently, the meaning of the whole composite expression or sentence is not a single representation, but a list of contextualized senses, namely the restricted distributions of its constituent (lexical) words. We report the results of two large-scale corpus-based experiments on two different natural language processing applications: paraphrasing and compositional translationThis work is funded by Project TELPARES, Ministry of Economy and Competitiveness (FFI2014-51978-C2-1-R), and the program “Ayuda Fundación BBVA a Investigadores y Creadores Culturales 2016”S

Process planning and metallurgical issues for laser asisted spin froming of dual phase automotive steel

Postprint (published version

Muchos problemas actuales proceden de tergiversaciones históricas

Entrevista publicada en prensa.Peer reviewe