222 research outputs found

    Document Retrieval on Repetitive Collections

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    Document retrieval aims at finding the most important documents where a pattern appears in a collection of strings. Traditional pattern-matching techniques yield brute-force document retrieval solutions, which has motivated the research on tailored indexes that offer near-optimal performance. However, an experimental study establishing which alternatives are actually better than brute force, and which perform best depending on the collection characteristics, has not been carried out. In this paper we address this shortcoming by exploring the relationship between the nature of the underlying collection and the performance of current methods. Via extensive experiments we show that established solutions are often beaten in practice by brute-force alternatives. We also design new methods that offer superior time/space trade-offs, particularly on repetitive collections.Comment: Accepted to ESA 2014. Implementation and experiments at http://www.cs.helsinki.fi/group/suds/rlcsa

    Aprovechamiento de desechos frutales en la producción de alcohol potable

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    En este trabajo se desarrolló un proceso para el aprovechamiento de desechos frutales, para producir alcohol potable. Se trabajó con desechos de ciruelas y manzanas provenientes de plantas de packing y deshidratado. Se determinó la influencia en el rendimiento alcohólico de: contenido inicial de sacarosa, concentración de levadura y temperatura de fermentación. Se realizaron las pruebas legales de potabilidad para determinar la posibilidad de consumo humano. Finalmente, se determinó el aumento de contenido proteico en las tortas de fermentación para un posible uso en alimentación animal. Las pruebas de potabilidad indicaron que los contenidos de impurezas fueron en todos los casos inferiores a los máx imos permitidos por la ley

    RLZAP: Relative Lempel-Ziv with Adaptive Pointers

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    Relative Lempel-Ziv (RLZ) is a popular algorithm for compressing databases of genomes from individuals of the same species when fast random access is desired. With Kuruppu et al.'s (SPIRE 2010) original implementation, a reference genome is selected and then the other genomes are greedily parsed into phrases exactly matching substrings of the reference. Deorowicz and Grabowski (Bioinformatics, 2011) pointed out that letting each phrase end with a mismatch character usually gives better compression because many of the differences between individuals' genomes are single-nucleotide substitutions. Ferrada et al. (SPIRE 2014) then pointed out that also using relative pointers and run-length compressing them usually gives even better compression. In this paper we generalize Ferrada et al.'s idea to handle well also short insertions, deletions and multi-character substitutions. We show experimentally that our generalization achieves better compression than Ferrada et al.'s implementation with comparable random-access times

    Cognitive impairment induced by delta9-tetrahydrocannabinol occurs through heteromers between cannabinoid CB1 and serotonin 5-HT2A receptors

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    Delta-9-tetrahydrocannabinol (THC), the main psychoactive compound of marijuana, induces numerous undesirable effects, including memory impairments, anxiety, and dependence. Conversely, THC also has potentially therapeutic effects, including analgesia, muscle relaxation, and neuroprotection. However, the mechanisms that dissociate these responses are still not known. Using mice lacking the serotonin receptor 5-HT2A, we revealed that the analgesic and amnesic effects of THC are independent of each other: while amnesia induced by THC disappears in the mutant mice, THC can still promote analgesia in these animals. In subsequent molecular studies, we showed that in specific brain regions involved in memory formation, the receptors for THC and the 5-HT2A receptors work together by physically interacting with each other. Experimentally interfering with this interaction prevented the memory deficits induced by THC, but not its analgesic properties. Our results highlight a novel mechanism by which the beneficial analgesic properties of THC can be dissociated from its cognitive side effects

    Creative innovation in Spanish construction firms

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    "This material may be downloaded for personal use only. Any other use requires prior permission of the American Society of Civil Engineers"Small and medium-sized contractors are characterized by organizational structures that are highly focused on control. As a result, employees concentrate on day-to-day activities with little time or motivation to generate creative ideas. Generally, the technological improvements of these companies arise as a result of problem-solving at the construction site. Nevertheless, the actual status quo is changing. In fact, some Spanish public agencies are already considering innovation as an added value in public procurement; thus, large contractors are starting to systemize their innovative efforts. This means that small and medium-sized enterprises must modify their attitudes towards innovation in order to sustain their competitiveness. The implementation of a system that enhances innovation and acquisition of knowledge may be the solution to overcome this disadvantage. The authors analyzed the implementation of an innovation management system in a Spanish construction firm of medium size for nine years. The system builds on a set of processes aimed to generate innovation projects that allow the contractor to document the innovation, not only for internal purposes related to knowledge management, but also for external ones associated with obtaining better results in public tenders. These processes are: (a) technology watch; (b) creativity; (c) planning and executing innovation projects; (d) technology transfer; and (e) protection of results. The last step is the feedback of the entire process through the assessment of the final outcomes. The implementation of the innovation system is ensured within the organization, through training of personnel, participation of stakeholders and encouragement of the innovation culture.The research reported in this paper was partially funded by the Universidad Catolica del Maule (UCM) [Project Mejoramiento de la Calidad y Equidad de la Educacion Superior (MECESUP)-UCM0205], the Spanish Ministry of Infrastructure (Project 2004-36), and the Universitat Politecnica de Valencia (UPV) (Contract UPV-2008-0629). Francisco Vea, Ricardo Lacort, and Manuel Civera are thanked for their help and support throughout the implementation of the system. Dr. Debra Westall is thanked for revising the text.Yepes, V.; Pellicer Armiñana, E.; Fernando Alarcón, L.; Correa Becerra, CL. (2015). Creative innovation in Spanish construction firms. Journal of Professional Issues in Engineering Education and Practice. 141:04015006-1-04015006-10. https://doi.org/10.1061/(ASCE)EI.1943-5541.0000251S04015006-104015006-1014

    Psychiatric diagnoses, trauma, and suicidiality

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    BACKGROUND: This study aimed to examine the associations between psychiatric diagnoses, trauma and suicidiality in psychiatric patients at intake. METHODS: During two months, all consecutive patients (n = 139) in a psychiatric hospital in Western Norway were interviewed (response rate 72%). RESULTS: Ninety-one percent had been exposed to at least one trauma; 69 percent had been repeatedly exposed to trauma for longer periods of time. Only 7% acquired a PTSD diagnosis. The comorbidity of PTSD and other psychiatric diagnoses were 78%. A number of diagnoses were associated with specific traumas. Sixty-seven percent of the patients reported suicidal thoughts in the month prior to intake; thirty-one percent had attempted suicide in the preceding week. Suicidal ideation, self-harming behaviour, and suicide attempts were associated with specific traumas. CONCLUSION: Traumatised patients appear to be under- or misdiagnosed which could have an impact on the efficiency of treatment

    Heteroreceptor complexes formed by dopamine D1, histamine H3 and N-methyl-D-aspartate glutamate receptors as targets to prevent neuronal death in Alzheimer's disease

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    Alzheimer’s disease (AD) is a neurodegenerative disorder causing progressive memory loss and cognitive dysfunction. Anti-AD strategies targeting cell receptors consider them as isolated units. However, many cell surface receptors cooperate and physically contact each other forming complexes having different biochemical properties than individual receptors. We here report the discovery of dopamine D , histamine H , and N-methylD-aspartate (NMDA) glutamate receptor heteromers in heterologous systems and in rodent brain cortex. Heteromers were detected by coimmunoprecipitation and in situ proximity ligation assays (PLA) in the rat cortex where H receptor agonists, via negative cross-talk, and H receptor antagonists, via cross-antagonism, decreased D receptor agonist signaling determined by ERK1/2 or Akt phosphorylation and counteracted D receptormediated excitotoxic cell death. Both D and H receptor antagonists also counteracted NMDA toxicity suggesting a complex interaction between NMDA receptors and D -H receptor heteromer function. Likely due to heteromerization, H receptors act as allosteric regulator for D and NMDA receptors. By bioluminescence resonance energy transfer (BRET), we demonstrated that D or H receptors form heteromers with NR1A/NR2B NMDA receptor subunits. D -H -NMDA receptor complexes were confirmed by BRET combined with fluorescence complementation. The endogenous expression of complexes in mouse cortex was determined by PLA and similar expression was observed in wild-type and APP/PS1 mice. Consistent with allosteric receptor-receptor interactions within the complex, H receptor antagonists reduced NMDA or D receptor-mediated excitotoxic cell death in cortical organotypic cultures. Moreover, H receptor antagonists reverted the toxicity induced by ß -amyloid peptide. Thus, histamine H receptors in D -H -NMDA heteroreceptor complexes arise as promising targets to prevent neurodegeneration
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