Robust decision analysis for environmental management of groundwater contamination sites

In contrast to many other engineering fields, the uncertainties in subsurface processes (e.g., fluid flow and contaminant transport in aquifers) and their parameters are notoriously difficult to observe, measure, and characterize. This causes severe uncertainties that need to be addressed in any decision analysis related to optimal management and remediation of groundwater contamination sites. Furthermore, decision analyses typically rely heavily on complex data analyses and/or model predictions, which are often poorly constrained as well. Recently, we have developed a model-driven decision-support framework (called MADS; http://mads.lanl.gov) for the management and remediation of subsurface contamination sites in which severe uncertainties and complex physics-based models are coupled to perform scientifically defensible decision analyses. The decision analyses are based on Information Gap Decision Theory (IGDT). We demonstrate the MADS capabilities by solving a decision problem related to optimal monitoring network design.Comment: This paper has been withdrawn by the author due to a crucial sign error in equations 7 and

Nonnegative/binary matrix factorization with a D-Wave quantum annealer

D-Wave quantum annealers represent a novel computational architecture and have attracted significant interest, but have been used for few real-world computations. Machine learning has been identified as an area where quantum annealing may be useful. Here, we show that the D-Wave 2X can be effectively used as part of an unsupervised machine learning method. This method can be used to analyze large datasets. The D-Wave only limits the number of features that can be extracted from the dataset. We apply this method to learn the features from a set of facial images

How stands the Tree of Life a century and a half after The Origin?

We examine the Tree of Life (TOL) as an evolutionary hypothesis and a heuristic. The original TOL hypothesis has failed but a new "statistical TOL hypothesis" is promising. The TOL heuristic usefully organizes data without positing fundamental evolutionary truth

WldS but not Nmnat1 protects dopaminergic neurites from MPP+ neurotoxicity

<p>Abstract</p> <p>Background</p> <p>The <it>Wld^S</it>mouse mutant ("Wallerian degeneration-slow") delays axonal degeneration in a variety of disorders including <it>in vivo </it>models of Parkinson's disease. The mechanisms underlying <it>Wld^S</it>-mediated axonal protection are unclear, although many studies have attributed <it>Wld^S</it>neuroprotection to the NAD⁺-synthesizing Nmnat1 portion of the fusion protein. Here, we used dissociated dopaminergic cultures to test the hypothesis that catalytically active Nmnat1 protects dopaminergic neurons from toxin-mediated axonal injury.</p> <p>Results</p> <p>Using mutant mice and lentiviral transduction of dopaminergic neurons, the present findings demonstrate that <it>Wld^S</it>but not Nmnat1, Nmnat3, or cytoplasmically-targeted Nmnat1 protects dopamine axons from the parkinsonian mimetic N-methyl-4-phenylpyridinium (MPP⁺). Moreover, NAD⁺synthesis is not required since enzymatically-inactive <it>Wld^S</it>still protects. In addition, NAD⁺by itself is axonally protective and together with <it>Wld^S</it>is additive in the MPP⁺model.</p> <p>Conclusions</p> <p>Our data suggest that NAD⁺and <it>Wld^S</it>act through separate and possibly parallel mechanisms to protect dopamine axons. As MPP⁺is thought to impair mitochondrial function, these results suggest that <it>Wld^S</it>might be involved in preserving mitochondrial health or maintaining cellular metabolism.</p

Receiving a diagnosis of young onset dementia: a scoping review of lived experiences

Objectives: Personal experiences of receiving a diagnosis of young onset dementia (YOD) are often overlooked in a complex assessment process requiring substantial investigation. A thematic synthesis of published until November 2018 qualitative studies was completed to understand the lived experiences of younger people. This informed a Delphi study to learn how diagnostic processes could be improved, identify the strengths and weaknesses of current approaches, and help educate professionals concerning key issues. Method: Systematic searches of bibliographic databases were conducted involving self-reported experiences of diagnosis of YOD. Eight out of 47 papers identified were quality assessed using Walsh & Browne's criteria for methodological appraisal. Results: The review emphasises that delays in diagnosis can often be attributed to (1) delays in accessing help, and (2) misattribution of symptoms by the clinician. The impact of diagnosis is influenced by the clinician's use of language; and reactions to diagnosis varied from feelings of reassurance (in that their symptoms are now explained), to shock and destabilisation. Conclusion: This review suggests that improving the recognition of presenting symptoms, reducing diagnostic errors, and identifying the emotional needs arising from diagnosis are required to improve the diagnostic experience for younger adults, and to promote future engagement with services

Discontinuous Galerkin spatial discretisation of the neutron transport equation with pyramid finite elements and a discrete ordinate (SN) angular approximation

In finite element analysis it is well known that hexahedral elements are the preferred type of three dimensional element because of their accuracy and convergence properties. However, in general it is not possible to mesh complex geometry problems using purely hexahedral meshes. Indeed for highly complex geometries a mixture of hexahedra and tetrahedra is often required. However, in order to geometrically link hexahedra and tetrahedra, in a conforming finite element mesh, pyramid elements will be required. Until recently the basis functions of pyramid elements were not fully understood from a mathematical or computational perspective. Indeed only first-order pyramid basis functions were rigorously derived and used within the field of finite elements. This paper makes use of a method developed by Bergot that enables the generation of second and higher-order basis functions, applying them to finite element discretisations of the neutron transport equation in order to solve nuclear reactor physics, radiation shielding and nuclear criticality problems. The results demonstrate that the pyramid elements perform well in almost all cases in terms of both solution accuracy and convergence properties

Establishing and sustaining high-quality services for people with young onset dementia: The perspective of senior service providers and commissioners

OBJECTIVES: We aimed to understand the facilitators to developing and sustaining high-quality services for people with young onset dementia (YOD) and their families/supporters. DESIGN: This qualitative study used semi-structured interviews with commissioners and service managers, analyzed using inductive thematic analysis. SETTING: A purposive sample of providers was selected from diverse areas and contrasting YOD services. PARTICIPANTS: Eighteen senior staff from YOD services and two dementia service commissioners took part. MEASUREMENTS: For commissioners, key interview topics were experiences of commissioning YOD services, perceived facilitators or barriers, and how future guidance should be structured for ease of use. For service providers, key topics explored experiences of delivering YOD services; what was achievable or challenging; how the service was funded; how it linked with broader provision for YOD in the area; and how guidance should be structured. RESULTS: Recorded interviews lasted 30–40 minutes. Seven key facilitators to the development and sustaining of YOD services were identified: having knowledgeable, committed local champions; involvement of people living with YOD and family supporters; initial delivery within existing resources; partnership working within and between sectors; having a reflective, supportive organizational culture; gathering evidence of impact; and having wider support and guidance. CONCLUSIONS: Improvements in provision for those with YOD and their families need to be built on understanding of service-level and interpersonal influences as well as on understanding of YOD itself. Our findings highlight a set of facilitators which need to be in place to establish and sustain high-quality YOD services that fit the local context

Living with young onset dementia and actively shaping dementia research - The Angela Project

Younger people living with dementia have been actively engaged in challenging society’s attitude to dementia. Despite their increased visibility though, there are substantial obstacles for younger people living with dementia in receiving a timely and accurate diagnosis and gaining access to appropriate support. Keith Oliver has been an active member of the Patient and Public Involvement Forum for the Angela Project, an Alzheimer’s Society funded project aimed at improving accuracy of diagnosis and post-diagnostic support for younger people living with dementia. In this article, Keith shares his experience of receiving a diagnosis of dementia and how he has since been involved in research projects, highlighting the benefits of Patient and Public Involvement for both the person living with dementia, as well as for the research group. Keith concludes by encouraging better Patient and Public Involvement practice in all projects, emphasising the benefits to all those involved in research