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Three Dimensional, Integrated Characterization and Archival System for Remote Facility Contaminant Characterization
The largest problem facing the Department of Energy's Office of Environmental Management (EM) is the cleanup of the Cold War legacy nuclear production plants that were built and operated from the mid-forties through the late eighties. EM is now responsible for the remediation of no less than 353 projects at 53 sites across the country at, an estimated cost of $147 billion over the next 72 years. One of the keys to accomplishing a thorough cleanup of any site is a rigorous but quick contaminant characterization capability. If the contaminants present in a facility can be mapped accurately, the cleanup can proceed with surgical precision, using appropriate techniques for each contaminant type and location. The three dimensional, integrated characterization and archival system (3D-ICAS) was developed for the purpose of rapid, field level identification, mapping, and archiving of contaminant data. The system consists of three subsystems, an integrated work and operating station, a 3-D coherent laser radar, and a contaminant analysis unit. Target contaminants that can be identified include chemical (currently organic only), radiological, and base materials (asbestos). In operation, two steps are required. First, the remotely operable 3-D laser radar maps an area of interest in the spatial domain. Second, the remotely operable contaminant analysis unit maps the area of interest in the chemical, radiological, and base material domains. The resultant information is formatted for display and archived using an integrated workstation. A 3-D model of the merged spatial and contaminant domains cart be displayed along with a color-coded contaminant tag at each analysis point. In addition, all of the supporting detailed data are archived for subsequent QC checks. The 3D-ICAS system is capable of performing all contaminant characterization in a dwell time of 6 seconds. The radiological and chemical sensors operate at US Environmental Protection Agency regulatory levels. Base materials identification is accomplished using a molecular vibrational spectroscopy, which can identify materials such as asbestos, concrete, wood, or transite. The multipurpose sensor head is positioned robotically using a small CRS Robotics A465 arm, which is registered to the environment map by the 3-D laser radar
Does the Red Queen reign in the kingdom of digital organisms?
In competition experiments between two RNA viruses of equal or almost equal
fitness, often both strains gain in fitness before one eventually excludes the
other. This observation has been linked to the Red Queen effect, which
describes a situation in which organisms have to constantly adapt just to keep
their status quo. I carried out experiments with digital organisms
(self-replicating computer programs) in order to clarify how the competing
strains' location in fitness space influences the Red-Queen effect. I found
that gains in fitness during competition were prevalent for organisms that were
taken from the base of a fitness peak, but absent or rare for organisms that
were taken from the top of a peak or from a considerable distance away from the
nearest peak. In the latter two cases, either neutral drift and loss of the
fittest mutants or the waiting time to the first beneficial mutation were more
important factors. Moreover, I found that the Red-Queen dynamic in general led
to faster exclusion than the other two mechanisms.Comment: 10 pages, 5 eps figure
Borcherds symmetries in M-theory
It is well known but rather mysterious that root spaces of the Lie
groups appear in the second integral cohomology of regular, complex, compact,
del Pezzo surfaces. The corresponding groups act on the scalar fields (0-forms)
of toroidal compactifications of M theory. Their Borel subgroups are actually
subgroups of supergroups of finite dimension over the Grassmann algebra of
differential forms on spacetime that have been shown to preserve the
self-duality equation obeyed by all bosonic form-fields of the theory. We show
here that the corresponding duality superalgebras are nothing but Borcherds
superalgebras truncated by the above choice of Grassmann coefficients. The full
Borcherds' root lattices are the second integral cohomology of the del Pezzo
surfaces. Our choice of simple roots uses the anti-canonical form and its known
orthogonal complement. Another result is the determination of del Pezzo
surfaces associated to other string and field theory models. Dimensional
reduction on corresponds to blow-up of points in general position
with respect to each other. All theories of the Magic triangle that reduce to
the sigma model in three dimensions correspond to singular del Pezzo
surfaces with (normal) singularity at a point. The case of type I and
heterotic theories if one drops their gauge sector corresponds to non-normal
(singular along a curve) del Pezzo's. We comment on previous encounters with
Borcherds algebras at the end of the paper.Comment: 30 pages. Besides expository improvements, we exclude by hand real
fermionic simple roots when they would naively aris
Consistent histories of systems and measurements in spacetime
Traditional interpretations of quantum theory in terms of wave function
collapse are particularly unappealing when considering the universe as a whole,
where there is no clean separation between classical observer and quantum
system and where the description is inherently relativistic. As an alternative,
the consistent histories approach provides an attractive "no collapse"
interpretation of quantum physics. Consistent histories can also be linked to
path-integral formulations that may be readily generalized to the relativistic
case. A previous paper described how, in such a relativistic spacetime path
formalism, the quantum history of the universe could be considered to be an
eignestate of the measurements made within it. However, two important topics
were not addressed in detail there: a model of measurement processes in the
context of quantum histories in spacetime and a justification for why the
probabilities for each possible cosmological eigenstate should follow Born's
rule. The present paper addresses these topics by showing how Zurek's concepts
of einselection and envariance can be applied in the context of relativistic
spacetime and quantum histories. The result is a model of systems and
subsystems within the universe and their interaction with each other and their
environment.Comment: RevTeX 4; 37 pages; v2 is a revision in response to reviewer
comments, connecting the discussion in the paper more closely to consistent
history concepts; v3 has minor editorial corrections; accepted for
publication in Foundations of Physics; v4 has a couple minor typographical
correction
Spacetime Coarse Grainings in the Decoherent Histories Approach to Quantum Theory
We investigate the possibility of assigning consistent probabilities to sets
of histories characterized by whether they enter a particular subspace of the
Hilbert space of a closed system during a given time interval. In particular we
investigate the case that this subspace is a region of the configuration space.
This corresponds to a particular class of coarse grainings of spacetime
regions. We consider the arrival time problem and the problem of time in
reparametrization invariant theories as for example in canonical quantum
gravity. Decoherence conditions and probabilities for those application are
derived. The resulting decoherence condition does not depend on the explicit
form of the restricted propagator that was problematic for generalizations such
as application in quantum cosmology. Closely related is the problem of
tunnelling time as well as the quantum Zeno effect. Some interpretational
comments conclude, and we discuss the applicability of this formalism to deal
with the arrival time problem.Comment: 23 pages, Few changes and added references in v
Genetic variation at MECOM, TERT, JAK2 and HBS1L-MYB predisposes to myeloproliferative neoplasms
Clonal proliferation in myeloproliferative neoplasms (MPN) is driven by somatic mutations in JAK2, CALR or MPL, but the contribution of inherited factors is poorly characterized. Using a three-stage genome-wide association study of 3,437 MPN cases and 10,083 controls, we identify two SNPs with genome-wide significance in JAK2V617F-negative MPN: rs12339666 (JAK2; meta-analysis P=1.27 Ă 10â10) and rs2201862 (MECOM; meta-analysis P=1.96 Ă 10â9). Two additional SNPs, rs2736100 (TERT) and rs9376092 (HBS1L/MYB), achieve genome-wide significance when including JAK2V617F-positive cases. rs9376092 has a stronger effect in JAK2V617F-negative cases with CALR and/or MPL mutations (BreslowâDay P=4.5 Ă 10â7), whereas in JAK2V617F-positive cases rs9376092 associates with essential thrombocythemia (ET) rather than polycythemia vera (allelic Ï2 P=7.3 Ă 10â7). Reduced MYB expression, previously linked to development of an ET-like disease in model systems, associates with rs9376092 in normal myeloid cells. These findings demonstrate that multiple germline variants predispose to MPN and link constitutional differences in MYB expression to disease phenotype
Cognitive behavioural therapy for clozapine-resistant schizophrenia: the FOCUS RCT
Background:
Clozapine (clozaril, Mylan Products Ltd) is a first-choice treatment for people with schizophrenia who have a poor response to standard antipsychotic medication. However, a significant number of patients who trial clozapine have an inadequate response and experience persistent symptoms, called clozapine-resistant schizophrenia (CRS). There is little evidence regarding the clinical effectiveness of pharmacological or psychological interventions for this population.
Objectives:
To evaluate the clinical effectiveness and cost-effectiveness of cognitiveâbehavioural therapy (CBT) for people with CRS and to identify factors predicting outcome.
Design:
The Focusing on Clozapine Unresponsive Symptoms (FOCUS) trial was a parallel-group, randomised, outcome-blinded evaluation trial. Randomisation was undertaken using permuted blocks of random size via a web-based platform. Data were analysed on an intention-to-treat (ITT) basis, using random-effects regression adjusted for site, age, sex and baseline symptoms. Cost-effectiveness analyses were carried out to determine whether or not CBT was associated with a greater number of quality-adjusted life-years (QALYs) and higher costs than treatment as usual (TAU).
Setting:
Secondary care mental health services in five cities in the UK.
Participants:
People with CRS aged up to 16 years, with an International Classification of Diseases, Tenth Revision (ICD-10) schizophrenia spectrum diagnoses and who are experiencing psychotic symptoms.
Interventions:
Individual CBT included up to 30 hours of therapy delivered over 9 months. The comparator was TAU, which included care co-ordination from secondary care mental health services.
Main outcome measures:
The primary outcome was the Positive and Negative Syndrome Scale (PANSS) total score at 21 months and the primary secondary outcome was PANSS total score at the end of treatment (9 months post randomisation). The health benefit measure for the economic evaluation was the QALY, estimated from the EuroQol-5 Dimensions, five-level version (EQ-5D-5L), health status measure. Service use was measured to estimate costs.
Results:
Participants were allocated to CBT (nâ=â242) or TAU (nâ=â245). There was no significant difference between groups on the prespecified primary outcome [PANSS total score at 21 months was 0.89 points lower in the CBT arm than in the TAU arm, 95% confidence interval (CI) â3.32 to 1.55 points; pâ=â0.475], although PANSS total score at the end of treatment (9 months) was significantly lower in the CBT arm (â2.40 points, 95% CI â4.79 to â0.02 points; pâ=â0.049). CBT was associated with a net cost of ÂŁ5378 (95% CI âÂŁ13,010 to ÂŁ23,766) and a net QALY gain of 0.052 (95% CI 0.003 to 0.103 QALYs) compared with TAU. The cost-effectiveness acceptability analysis indicated a low likelihood that CBT was cost-effective, in the primary and sensitivity analyses (probability <â50%). In the CBT arm, 107 participants reported at least one adverse event (AE), whereas 104 participants in the TAU arm reported at least one AE (odds ratio 1.09, 95% CI 0.81 to 1.46; pâ=â0.58).
Conclusions:
Cognitiveâbehavioural therapy for CRS was not superior to TAU on the primary outcome of total PANSS symptoms at 21 months, but was superior on total PANSS symptoms at 9 months (end of treatment). CBT was not found to be cost-effective in comparison with TAU. There was no suggestion that the addition of CBT to TAU caused adverse effects. Future work could investigate whether or not specific therapeutic techniques of CBT have value for some CRS individuals, how to identify those who may benefit and how to ensure that effects on symptoms can be sustained.
Trial registration:
Current Controlled Trials ISRCTN99672552
The organics revolution: new narratives and how we can achieve them
Organic remains from excavated sites include a wide range of materials, from distinct organisms (âecofactsâ) to biomolecules. Biomolecules provide a variety of new research avenues, while ecofacts with longer histories of study are now being re-harnessed in unexpected ways. These resources are unlocking research potential, transcending what was previously imagined possible. However, this âorganics revolutionâ comes with a salutary corollary: our approaches to recovering and curating organics, and making accessible research data, are not developing as quickly as we need. In this paper, we review retention guidelines for institutions in Britain and Ireland, setting this against the backdrop of a âcuration crisisâ that is affecting museums throughout Europe, and beyond. We suggest key themes, including the state of existing documentation and considerations of intrinsic and allied research potential, that should be used to open a discussion about the development of more comprehensive and standardised approaches to archiving in the future. Engaging in this conversation is the only way that we can hope to ensure the long-term retention and preservation of organics, while safeguarding associated research data. These changes are needed to ensure future global research collaborations across the academic, curatorial and professional archaeological sectors
Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment
This paper describes an analysis of the angular distribution of W->enu and
W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with
the ATLAS detector at the LHC in 2010, corresponding to an integrated
luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and
the missing transverse energy, the W decay angular distribution projected onto
the transverse plane is obtained and analysed in terms of helicity fractions
f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV
and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw
> 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour,
are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017
+/- 0.030, where the first uncertainties are statistical, and the second
include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables,
revised author list, matches European Journal of Physics C versio
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