379 research outputs found

    Parameterized Complexity Results for Plan Reuse

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    Planning is a notoriously difficult computational problem of high worst-case complexity. Researchers have been investing significant efforts to develop heuristics or restrictions to make planning practically feasible. Case-based planning is a heuristic approach where one tries to reuse previous experience when solving similar problems in order to avoid some of the planning effort. Plan reuse may offer an interesting alternative to plan generation in some settings. We provide theoretical results that identify situations in which plan reuse is provably tractable. We perform our analysis in the framework of parameterized complexity, which supports a rigorous worst-case complexity analysis that takes structural properties of the input into account in terms of parameters. A central notion of parameterized complexity is fixed-parameter tractability which extends the classical notion of polynomial-time tractability by utilizing the effect of structural properties of the problem input. We draw a detailed map of the parameterized complexity landscape of several variants of problems that arise in the context of case-based planning. In particular, we consider the problem of reusing an existing plan, imposing various restrictions in terms of parameters, such as the number of steps that can be added to the existing plan to turn it into a solution of the planning instance at hand.Comment: Proceedings of AAAI 2013, pp. 224-231, AAAI Press, 201

    The dark side of artificial greening: Plastic turfs as widespread pollutants of aquatic environments

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    Artificial turf (AT) is a surfacing material that simulates natural grass by using synthetic, mainly plastic, fibers in different shapes, sizes and properties. AT has spread beyond sports facilities and today shapes many urban landscapes, from private lawns to rooftops and public venues. Despite concerns regarding the impacts of AT, little is known about the release of AT fibers into natural environment. Here, for the first time, we specifically investigate the presence of AT fibers in river and ocean waters as major conduits and final destination of plastic debris transported by water runoff. Our sampling survey showed that, AT fibers – composed mainly of polyethylene and polypropylene – can constitute over 15% of the mesoplastics and macroplastics content, suggesting that AT fibers may contribute significantly to plastic pollution. Up to 20,000 fibers a day flowed down through the river, and up to 213,200 fibers per km2 were found floating on the sea surface of nearshore areas. AT, apart from impacting on urban biodiversity, urban runoff, heat island formation, and hazardous chemical leaching, is a major source of plastic pollution to natural aquatic environments

    Taste, smell and mouthfeel disturbances in patients with gastrointestinal stromal tumors treated with tyrosine-kinase inhibitors

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    CONTEXT: Taste, smell, and mouthfeel disturbances are underrated and underreported, but important side effects of anti-cancer medication. These symptoms are associated with a lower quality of life (QoL). The prevalence and the impact of taste, smell, and mouthfeel disturbances on daily life in patients with a gastrointestinal stromal tumor (GIST) are largely unknown. OBJECTIVES: This exploratory study assessed the prevalence and type of taste, smell, and mouthfeel disturbances and their impact on daily life and QoL in patients with a GIST treated with a tyrosine-kinase inhibitor (TKI). METHODS: Patients currently treated with TKIs for GIST completed a standardized questionnaire. The questionnaire addressed changes in taste, smell, and mouthfeel and, if changes occurred, impact on daily life and QoL. Statistics are descriptive. RESULTS: A total of 65 GIST patients on TKI treatment completed the questionnaire. Of these patients, 79%, 12%, and 9% currently used imatinib, sunitinib, and regorafenib respectively. Taste, smell, and mouthfeel disturbances were reported by 25 (38%), 15 (23%), and 36 (55%) patients respectively. Salty and sweet tastes were mostly affected, respectively in 14 and 13 patients. A dry mouth was experienced by 29 (45%) patients. Taste disturbances were more often reported to have impact on daily life and QoL (80% and 60%) than smell (47% and 31%) and mouthfeel disturbances (47% and 30%). CONCLUSION: Taste, smell, and mouthfeel disturbances are frequent side effects of TKIs in GIST patients. Daily life and QoL are affected in a considerable number of those patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NL7827 (2019-06-25)

    Self-reported taste and smell alterations and the liking of oral nutritional supplements with sensory-adapted flavors in cancer patients receiving systemic antitumor treatment

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    Purpose Taste and smell alterations (TAs and SAs) are often reported by patients with cancer receiving systemic antitumor therapy and can negatively impact food intake and quality of life. This study aimed to examine the occurrence of TAs and SAs and investigate the impact of TAs on overall liking of oral nutritional supplements (ONS) with warming and cooling sensations. Methods Patients receiving systemic antitumor therapy completed a questionnaire on sensory alterations and evaluated overall liking of 5 prototype flavors of Nutridrink (R) Compact Protein (hot tropical ginger (HTG), hot mango (HM), cool red fruits (CRF), cool lemon (CL), and neutral (N)) on a 10-point scale via a sip test. Differences between patients with and without TAs were investigated using permutation analysis. Results Fifty patients with various cancer types and treatments were included. Thirty patients (60%) reported TAs and 13 (26%) experienced SAs. Three flavors were rated highly with a liking score > 6 (CRF 6.8 +/- 1.7; N 6.5 +/- 1.9; HTG 6.0 +/- 2.0). Larger variation in ONS liking scores was observed in patients with TAs with or without SAs (4.5-6.9 and 4.6-7.2, respectively) vs. patients without TAs (5.9-6.5). TAs were associated with increased liking of CRF (Delta = + 0.9) and N (Delta = + 1.0) flavors. Conclusions TAs and SAs are common in patients with cancer undergoing systemic antitumor therapy. Patients with TAs were more discriminant in liking of ONS flavors compared to patients without TAs, and sensory-adapted flavors appeared to be appreciated. The presence of TAs should be considered when developing or selecting ONS for patients with cancer

    Pre-verbal infants perceive emotional facial expressions categorically

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    Adults perceive emotional expressions categorically, with discrimination being faster and more accurate between expressions from different emotion categories (i.e. blends with two different predominant emotions) than between two stimuli from the same category (i.e. blends with the same predominant emotion). The current study sought to test whether facial expressions of happiness and fear are perceived categorically by pre-verbal infants, using a new stimulus set that was shown to yield categorical perception in adult observers (Experiments 1 and 2). These stimuli were then used with 7-month-old infants (N  =  34) using a habituation and visual preference paradigm (Experiment 3). Infants were first habituated to an expression of one emotion, then presented with the same expression paired with a novel expression either from the same emotion category or from a different emotion category. After habituation to fear, infants displayed a novelty preference for pairs of between-category expressions, but not within-category ones, showing categorical perception. However, infants showed no novelty preference when they were habituated to happiness. Our findings provide evidence for categorical perception of emotional expressions in pre-verbal infants, while the asymmetrical effect challenges the notion of a bias towards negative information in this age group

    Effect of painful Ledderhose disease on dynamic plantar foot pressure distribution during walking:a case-control study

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    Background: Plantar pressure distribution during walking in patients with painful Ledderhose disease is unknown.Research question: Do patients with painful Ledderhose disease have an altered plantar pressure distribution during walking compared to individuals without foot pathologies? It was hypothesized that plantar pressure is shifted away from the painful nodules.Methods: Pedobarography data of 41 patients with painful Ledderhose disease (cases, mean age: 54.2 ± 10.4 years) was collected and compared to pedobarography data from 41 individuals without foot pathologies (controls, mean age: 21.7 ± 2.0 years). Peak Pressure (PP), Maximum Mean Pressure (MMP) and Force-Time Integral (FTI) were calculated for eight regions (heel, medial midfoot, lateral midfoot, medial forefoot, central forefoot, lateral forefoot, hallux and other toes) under the soles of the feet. Differences between cases and controls were calculated and analysed by means of linear (mixed models) regression.Results: Proportional differences in PP, MMP and FTI showed increased values for the cases compared to the controls, especially in the heel, hallux and other toes regions, and decreased values in the medial- and lateral midfoot regions. In naïve regression analysis, being a patient was a predictor for increased- and decreased values for PP, MMP and FTI for several regions. When dependencies in the data were taken into account with linear mixed-model regression analysis, the increased- and decreased values for the patients were most prevalent for FTI at the heel, medial midfoot, hallux and other toes regions.Significance: In patients with painful Ledderhose disease, during walking, a shift of pressure was found towards the proximal and distal foot regions, while offloading the midfoot regions.</p

    Longitudinal fNIRS and EEG metrics of habituation and novelty detection are correlated in 1–18-month-old infants

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    Introduction: Habituation and novelty detection are two fundamental and widely studied neurocognitive processes. Whilst neural responses to repetitive and novel sensory input have been well-documented across a range of neuroimaging modalities, it is not yet fully understood how well these different modalities are able to describe consistent neural response patterns. This is particularly true for infants and young children, as different assessment modalities might show differential sensitivity to underlying neural processes across age. Thus far, many neurodevelopmental studies are limited in either sample size, longitudinal scope or breadth of measures employed, impeding investigations of how well common developmental trends can be captured via different methods./ Method: This study assessed habituation and novelty detection in N = 204 infants using EEG and fNIRS measured in two separate paradigms, but within the same study visit, at 1, 5 and 18 months of age in an infant cohort in rural Gambia. EEG was acquired during an auditory oddball paradigm during which infants were presented with Frequent, Infrequent and Trial Unique sounds. In the fNIRS paradigm, infants were familiarised to a sentence of infant-directed speech, novelty detection was assessed via a change in speaker. Indices for habituation and novelty detection were extracted for both EEG and NIRS./ Results: We found evidence for weak to medium positive correlations between responses on the fNIRS and the EEG paradigms for indices of both habituation and novelty detection at most age points. Habituation indices correlated across modalities at 1 month and 5 months but not 18 months of age, and novelty responses were significantly correlated at 5 months and 18 months, but not at 1 month. Infants who showed robust habituation responses also showed robust novelty responses across both assessment modalities./ Discussion: This study is the first to examine concurrent correlations across two neuroimaging modalities across several longitudinal age points. Examining habituation and novelty detection, we show that despite the use of two different testing modalities, stimuli and timescale, it is possible to extract common neural metrics across a wide age range in infants. We suggest that these positive correlations might be strongest at times of greatest developmental change

    SORTA:a system for ontology-based re-coding and technical annotation of biomedical phenotype data

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    There is an urgent need to standardize the semantics of biomedical data values, such as phenotypes, to enable comparative and integrative analyses. However, it is unlikely that all studies will use the same data collection protocols. As a result, retrospective standardization is often required, which involves matching of original (unstructured or locally coded) data to widely used coding or ontology systems such as SNOMED CT (clinical terms), ICD-10 (International Classification of Disease) and HPO (Human Phenotype Ontology). This data curation process is usually a time-consuming process performed by a human expert. To help mechanize this process, we have developed SORTA, a computer-aided system for rapidly encoding free text or locally coded values to a formal coding system or ontology. SORTA matches original data values (uploaded in semicolon delimited format) to a target coding system (uploaded in Excel spreadsheet, OWL ontology web language or OBO open biomedical ontologies format). It then semi-automatically shortlists candidate codes for each data value using Lucene and n-gram based matching algorithms, and can also learn from matches chosen by human experts. We evaluated SORTA's applicability in two use cases. For the LifeLines biobank, we used SORTA to recode 90 000 free text values (including 5211 unique values) about physical exercise to MET (Metabolic Equivalent of Task) codes. For the CINEAS clinical symptom coding system, we used SORTA to map to HPO, enriching HPO when necessary (315 terms matched so far). Out of the shortlists at rank 1, we found a precision/recall of 0.97/0.98 in LifeLines and of 0.58/0.45 in CINEAS. More importantly, users found the tool both a major time saver and a quality improvement because SORTA reduced the chances of human mistakes. Thus, SORTA can dramatically ease data (re) coding tasks and we believe it will prove useful for many more projects

    Van bescherming naar inclusie:Een handboek voor leerkrachten over uithuisgeplaatste kinderen en geadopteerde kinderen

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    Een handboek voor leerkrachten over uithuisgeplaatste kinderen en geadopteerde kinderen. Dit handboek is ontwikkeld in het kader van het project BRIGTHERFUTURE: Innovative tools for developing full potential after early adversity, waarvan het werkteam bestaat uit de volgende entiteiten: - Comune di Torino (ItaliĂ«) - CORA (Spanje) - PAC UK/ Family Action (Verenigd Koninkrijk) - Pharos Expertisecentrum Gezondheidsverschillen (Nederland) - Universitat AutĂČnoma de Barcelona (Spanje) - UniversitĂ  di Verona (ItaliĂ«) - Rijksuniversiteit Groningen (Nederland)Redacteur:Beatriz San RomĂĄn (Universitat AutĂČnoma de Barcelona)Medewerkers:Barbara Ferrero en Sandra Patt (Comune di Torino)Ana MÂȘ Linares, Águeda Ruibal en Chus VĂĄzquez Paredes (CORA)Rebecca Wilkins en Jo Mitchell (PAC UK, onderdeel van Family Action)Anna de Haan en Marjolein Keij (Pharos ExpertisecentrumGezondheidsverschillen)Chandra K. Clemente, Beatriz San RomĂĄn en Aida Urrea (UniversitatAutĂČnoma de Barcelona)Federica de Cordova, Giulia Selmi en Chiara SitĂ  (UniversitĂ  di Verona)MĂłnica LĂłpez LĂłpez, Elianne Zijlstra, Carla van Os en Mijntje tenBrummelaar (Rijksuniversiteit Groningen)<br/
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