387 research outputs found

    Refining complexity analyses in planning by exploiting the exponential time hypothesis

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    The use of computational complexity in planning, and in AI in general, has always been a disputed topic. A major problem with ordinary worst-case analyses is that they do not provide any quantitative information: they do not tell us much about the running time of concrete algorithms, nor do they tell us much about the running time of optimal algorithms. We address problems like this by presenting results based on the exponential time hypothesis (ETH), which is a widely accepted hypothesis concerning the time complexity of 3-SAT. By using this approach, we provide, for instance, almost matching upper and lower bounds onthe time complexity of propositional planning.Funding Agencies|National Graduate School in Computer Science (CUGS), Sweden; Swedish Research Council (VR) [621-2014-4086]</p

    The FERRUM project: Transition probabilities for forbidden lines in [FeII] and experimental metastable lifetimes

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    Accurate transition probabilities for forbidden lines are important diagnostic parameters for low-density astrophysical plasmas. In this paper we present experimental atomic data for forbidden [FeII] transitions that are observed as strong features in astrophysical spectra. Aims: To measure lifetimes for the 3d^6(^3G)4s a ^4G_{11/2} and 3d^6(^3D)4s b ^4D_{1/2} metastable levels in FeII and experimental transition probabilities for the forbidden transitions 3d^7 a ^4F_{7/2,9/2}- 3d^6(^3G)4s a ^4G_{11/2}. Methods: The lifetimes were measured at the ion storage ring facility CRYRING using a laser probing technique. Astrophysical branching fractions were obtained from spectra of Eta Carinae, obtained with the Space Telescope Imaging Spectrograph onboard the Hubble Space Telescope. The lifetimes and branching fractions were combined to yield absolute transition probabilities. Results: The lifetimes of the a ^4G_{11/2} and the b ^4D_{1/2} levels have been measured and have the following values, 0.75(10) s and 0.54(3) s respectively. Furthermore, we have determined the transition probabilities for two forbidden transitions of a ^4F_{7/2,9/2}- a ^4G_{11/2} at 4243.97 and 4346.85 A. Both the lifetimes and the transition probabilities are compared to calculated values in the literature.Comment: 5 pages, accepted for publication in A&

    NfL as a biomarker for neurodegeneration and survival in Parkinson disease

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    OBJECTIVE: To determine if Neurofilament Light chain protein in cerebrospinal fluid (cNfL); a sensitive biomarker of neuroaxonal damage, reflects disease severity or can predict survival in Parkinson's disease (PD). METHODS: We investigated if disease severity, phenotype or survival in patients with new-onset PD correlates with cNfL concentrations around the time of diagnosis in the population-based NYPUM study cohort (n = 99). A second, larger new-onset PD cohort (n = 194) was used for independent validation. Association of brain pathology with the cNfL concentration was examined using striatal dopamine transporter imaging and repeated diffusion tensor imaging, at baseline, 1 and 3 years. RESULTS: Higher cNfL in the early phase of PD was associated with greater severity of all cardinal motor symptoms except tremor, in both cohorts, and with shorter survival and impaired olfaction. cNfL concentrations above the median of 903 ng/L conferred an overall 5.8 times increased hazard of death, during follow-up. After adjustment for age and sex, higher cNfL correlated with striatal dopamine transporter uptake deficits and lower fractional anisotropy in diffusion tensor imaging of several axonal tracts. CONCLUSIONS: cNfL shows usefulness as a biomarker of disease severity and to predict survival in PD. The present results indicate that the cNfL concentration reflects the intensity of the neurodegenerative process, which could be of importance in future clinical trials. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that in patients with PD, cNFL concentrations are associated with more severe disease and shorter survival

    Integrating isotopes and documentary evidence : dietary patterns in a late medieval and early modern mining community, Sweden

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    We would like to thank the Archaeological Research Laboratory, Stockholm University, Sweden and the Tandem Laboratory (Ångström Laboratory), Uppsala University, Sweden, for undertaking the analyses of stable nitrogen and carbon isotopes in both human and animal collagen samples. Also, thanks to Elin Ahlin Sundman for providing the δ13C and δ15N values for animal references from Västerås. This research (Bäckström’s PhD employment at Lund University, Sweden) was supported by the Berit Wallenberg Foundation (BWS 2010.0176) and Jakob and Johan Söderberg’s foundation. The ‘Sala project’ (excavations and analyses) has been funded by Riksens Clenodium, Jernkontoret, Birgit and Gad Rausing’s Foundation, SAU’s Research Foundation, the Royal Physiographic Society of Lund, Berit Wallenbergs Foundation, Åke Wibergs Foundation, Lars Hiertas Memory, Helge Ax:son Johnson’s Foundation and The Royal Swedish Academy of Sciences.Peer reviewedPublisher PD

    Cerebrospinal Fluid Biomarkers of Synaptic Dysfunction Are Altered in Parkinson's Disease and Related Disorders

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    Background: Synaptic dysfunction and degeneration are central contributors to the pathogenesis and progression of parkinsonian disorders. Therefore, identification and validation of biomarkers reflecting pathological synaptic alterations are greatly needed and could be used in prognostic assessment and to monitor treatment effects. Objective: To explore candidate biomarkers of synaptic dysfunction in Parkinson's disease (PD) and related disorders. Methods: Mass spectrometry was used to quantify 15 synaptic proteins in two clinical cerebrospinal fluid (CSF) cohorts, including PD (n1 = 51, n2 = 101), corticobasal degeneration (CBD) (n1 = 11, n2 = 3), progressive supranuclear palsy (PSP) (n1 = 22, n2 = 21), multiple system atrophy (MSA) (n1 = 31, n2 = 26), and healthy control (HC) (n1 = 48, n2 = 30) participants, as well as Alzheimer's disease (AD) (n2 = 23) patients in the second cohort. Results: Across both cohorts, lower levels of the neuronal pentraxins (NPTX; 1, 2, and receptor) were found in PD, MSA, and PSP, compared with HC. In MSA and PSP, lower neurogranin, AP2B1, and complexin-2 levels compared with HC were observed. In AD, levels of 14-3-3 zeta/delta, beta- and gamma-synuclein were higher compared with the parkinsonian disorders. Lower pentraxin levels in PD correlated with Mini-Mental State Exam scores and specific cognitive deficits (NPTX2; rho = 0.25–0.32, P < 0.05) and reduced dopaminergic pre-synaptic integrity as measured by DaTSCAN (NPTX2; rho = 0.29, P = 0.023). Additionally, lower levels were associated with the progression of postural imbalance and gait difficulty symptoms (All NPTX; β-estimate = −0.025 to −0.038, P < 0.05) and cognitive decline (NPTX2; β-estimate = 0.32, P = 0.021). Conclusions: These novel findings show different alterations of synaptic proteins in parkinsonian disorders compared with AD and HC. The neuronal pentraxins may serve as prognostic CSF biomarkers for both cognitive and motor symptom progression in PD. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society

    A bridge between a lonely soul and the surrounding world: A study on existential consequences of being closely related to a person with aphasia

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    This study illuminates existential consequences of being closely related to a person suffering from aphasia. Seventeen close relatives were interviewed and their narratives were interpreted with inspiration from Ricoeur, Levinas, Husserl, Winnicot, and Maurice Merleau-Ponty. The emerging interpretations resulted in four themes that illuminate a life characterized by lost freedom, staying, a new form of relationship, and growing strong together with others. An overarching theme suggests that a life together with an aphasic person means being used as a bridge between the aphasic person and the surrounding world. Moreover, it illuminates that a close relative to a person with aphasia is a person who does not leave, despite a heavy burden of lonely responsibility. It is concluded that community services need to fulfill their responsibility of providing support to informal caregivers as suggested by the Swedish lawmakers

    Information and feedback to improve occupational physicians’ reporting of occupational diseases: a randomised controlled trial

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    To assess the effectiveness of supplying occupational physicians (OPs) with targeted and stage-matched information or with feedback on reporting occupational diseases to the national registry in the Netherlands. In a randomized controlled design, 1076 OPs were divided into three groups based on previous reporting behaviour: precontemplators not considering reporting, contemplators considering reporting and actioners reporting occupational diseases. Precontemplators and contemplators were randomly assigned to receive stage-matched, stage-mismatched or general information. Actioners were randomly assigned to receive personalized or standardized feedback upon notification. Outcome measures were the number of OPs reporting and the number of reported occupational diseases in a 180-day period before and after the intervention. Precontemplators were significantly more male and self-employed compared to contemplators and actioners. There was no significant effect of stage-matched information versus stage-mismatched or general information on the percentage of reporting OPs and on the mean number of notifications in each group. Receiving any information affected reporting more in contemplators than in precontemplators. The mean number of notifications in actioners increased more after personalized feedback than after standardized feedback, but the difference was not significant. This study supports the concept that contemplators are more susceptible to receiving information but could not confirm an effect of stage-matching this information on reporting occupational diseases to the national registr

    Controversial significance of early S100B levels after cardiac surgery

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    BACKGROUND: The brain-derived protein S100B has been shown to be a useful marker of brain injury of different etiologies. Cognitive dysfunction after cardiac surgery using cardiopulmonary bypass has been reported to occur in up to 70% of patients. In this study we tried to evaluate S100B as a marker for cognitive dysfunction after coronary bypass surgery with cardiopulmonary bypass in a model where the inflow of S100B from shed mediastinal blood was corrected for. METHODS: 56 patients scheduled for coronary artery bypass grafting underwent prospective neuropsychological testing. The test scores were standardized and an impairment index was constructed. S100B was sampled at the end of surgery, hourly for the first 6 hours, and then 8, 10, 15, 24 and 48 hours after surgery. None of the patients received autotransfusion. RESULTS: In simple linear analysis, no significant relation was found between S100B levels and neuropsychological outcome. In a backwards stepwise regression analysis the three variables, S100B levels at the end of cardiopulmonary bypass, S100B levels 1 hour later and the age of the patients were found to explain part of the neuropsychological deterioration (r = 0.49, p < 0.005). CONCLUSIONS: In this study we found that S100B levels 1 hour after surgery seem to be the most informative. Our attempt to control the increased levels of S100B caused by contamination from the surgical field did not yield different results. We conclude that the clinical value of S100B as a predictive measurement of postoperative cognitive dysfunction after cardiac surgery is limited

    GBA and APOE Impact Cognitive Decline in Parkinson's Disease : A 10-Year Population-Based Study

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    Acknowledgments: We would like to thank all participants, study personnel from each study, and funders of individual studies and of PICC. We would like to thank Artur Wozniak and Adrian Martin from the University of Aberdeen, Data Management Department, for help in developing the PICC database. We acknowledge the contributions of members of the individual study groups as detailed below. Members of PICC Steering Group: Dr. Angus D. Macleod, Dr. Carl E. Counsell (Chair), University of Aberdeen, UK; Prof. Ole-Bjørn Tysnes, University of Bergen, Norway; Marta Camacho, Dr. Caroline WilliamsGray, University of Cambridge, UK; Dr. Rachael A. Lawson, Newcastle University, UK; Dr. Jodi Maple-Grødem, Prof. Guido Alves, Stavanger University Hospital, Norway; Prof. Lars Forgren, Umeå University, Sweden. CamPaIGN study: Roger A. Barker, Thomas Foltynie, Sarah L. Mason, Caroline H. Williams-Gray. ICICLE-PD Study: David Burn, Lynn Rochester, Alison J. Yarnall, Rachael A. Lawson, Gordon W. Duncan, Tien K. Khoo. NYPUM Study: Lars Forsgren, Jan Linder, Mona Edström, Jörgen Andersson, Linda Eriksson, David Bäckström, Gun-Marie Hariz, Magdalena Domellöf. ParkWest Study: ParkWest Principal investigators: Guido Alves (Norwegian Centre for Movement Disorders, Stavanger University Hospital) and Ole-Bjørn Tysnes (Haukeland University Hospital). Study personnel: Michaela Dreetz Gjerstad, Kenn Freddy Pedersen, Elin Bjelland Forsaa, Veslemøy Hamre Frantzen, Anita Laugaland, Jodi MapleGrødem, Johannes Lange, Karen Simonsen, Eldbjørg Fiske and Ingvild Dalen (Stavanger University Hospital); Bernd Müller, Geir Olve Skeie and Marit Renså (Haukeland University Hospital); Wenche Telstad, Aliaksei Labusau and Jane Kastet (Førde Hospital); Ineke HogenEsch, Marianne Kjerandsen and Liv Kari Håland (Haugesund Hospital); Karen Herlofson, Solgunn Ongre, and Siri Bruun (Sørlandet Hospital Arendal). PICNICS study: Roger A. Barker, Marta Camacho, Gemma Cummins, Jonathan R. Evans, David P. Breen, Ruwani S. Wijeyekoon, Caroline H. Williams-Gray. PINE Study: Medical: Carl E. Counsell, Kate S. M. Taylor, Robert Caslake, Angus D. Macleod, David J. M. McGhee, Diane Swallow; Research nurse/assistant: Joanne Gordon, Clare Harris, Ann Hayman, Nicola Johannesson, Hazel Forbes; Data management: Valerie Angus, Alasdair Finlayson, David Dawson, Katie Wilde, David Ritchie, Artur Wozniak; Statisticians: Neil Scott, Shona Fielding; Radiology: Prof. Alison Murray; Pathology: Ishbel Gall, Dr. James MacKenzie, Prof. Colin Smith; Secretarial: Aileen Sylvester, Susan Mitchell, Pam Rebecca, Ann Christie, and Diane McCosh. Funding agencies: This work was supported by the Research Council of Norway (287842). The CamPaIGN study has received funding from the Wellcome Trust, the Medical Research Council, the Patrick Berthoud Trust, and the NIHR Cambridge Biomedical Research Centre (BRC-1215-20014). The ICICLE-PD study was funded by Parkinson’s UK (J-0802, G-1301, G-1507) and supported by the Lockhart Parkinson’s Disease Research Fund, National Institute for Health Research (NIHR) Newcastle Biomedical Research Unit and Centre based at Newcastle upon Tyne Hospitals NHS Foundation Trust and Newcastle University. The NYPUM study was supported by grants from the Swedish Medical Research Council, Erling-Persson Foundation, the Swedish Brain Foundation (Hjärnfonden), Umeå University, Västerbotten County Council, King Gustaf V and Queen Victoria Freemason Foundation, Swedish Parkinson Foundation, Swedish Parkinson Research Foundation, Kempe Foundation, Swedish PD Association, the European Research Council, and the Knut and Alice Wallenberg Foundation. The Norwegian ParkWest study has received funding from the Research Council of Norway (177966), the Western Norway Regional Health Authority (911218), the Norwegian Parkinson’s Research Foundation, and Rebergs Legacy. The PICNICS study was funded by the Cure Parkinson’s Trust, the Van Geest Foundation, the Medical Research Council, Parkinson’s UK, and the NIHR Cambridge Biomedical Research Centre (BRC-1215-20014). The PINE study was funded by Parkinson’s UK (grant numbers G0502, G0914, and G1302), the Scottish Chief Scientist Office (CAF/12/05, PCL/17/10), Academy of Medical Sciences, NHS Grampian endowments, the BMA Doris Hillier award, RS Macdonald Trust, the BUPA Foundation, and SPRING. The PICC collaboration has been supported by The Chief Scientist Office of the Scottish Government (PCL/17/10), the Academy of Medical Sciences, Parkinson’s UK (initial collaborator meeting) and the Norwegian Association for Public Health. C.R.S.’s work was supported by NIH grants NINDS/NIA R01NS115144, U01NS095736, U01NS100603, and the American Parkinson Disease Association Center for Advanced Parkinson Research. This research was funded in whole, or in part by the UKRI Medical Research Council [MR/R007446/1]. For the purpose of open access, the author has applied a CC BY public copyright licence to any Author Accepted Manuscript version arising from this submission.Peer reviewedPublisher PD
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