680 research outputs found
The Beginning of the End of the Anthropic Principle
We argue that if string theory as an approach to the fundamental laws of
physics is correct, then there is almost no room for anthropic arguments in
cosmology. The quark and lepton masses and interaction strengths are
determined.Comment: 12 page
Exploring Pathways from Data to Knowledge to Insights in the Pharmaceutical Industry: ‘Introducing the Pharmaceutical Knowledge Ecosystem’
The ecosystem of how the pharmaceutical industry acquires data, transforms these data into tangible knowledge, and derives valuable insights throughout the process, is highly complex. Data, information, knowledge, and the resulting insights, are necessary to support decision- making, manage risk, problem solve, ensure product realisation, enable continual improvement, and enhance operational effectiveness. Building on the fundamental concepts established in the well-known Data Information Knowledge Wisdom (DIKW) hierarchy, this paper reviews the basic concepts involved in the DIKW pathway and begins to relate these concepts to both established capabilities (e.g., PAT), existing requirements (e.g., data integrity), and emerging trends in the industry (e.g., industry 4.0). This paper introduces additional research studies which the Pharmaceutical Regulatory Science Team (PRST) is considering, regarding how one might apply systems thinking concepts to develop a framework which will enable key stakeholders (Industry, Regulatory and Academia) to better relate the many elements of this ecosystem. The paper concludes by identifying preliminary foundational principles which could form the basis of such a framework, coined by the authors as ‘The pharmaceutical knowledge ecosystem’, and makes the case for further exploration of this concept
Stability of the nonlinear dynamics of an optically injected VCSEL
Automated protocols have been developed to characterize time series data in terms of stability. These techniques are applied to the output power time series of an optically injected vertical cavity surface emitting laser (VCSEL) subject to varying injection strength and optical frequency detuning between master and slave lasers. Dynamic maps, generated from high resolution, computer controlled experiments, identify regions of dynamic instability in the parameter space. © 2012 Optical Society of America
Non-singular inflation with vacuum decay
On the basis of a semi-classical analysis of vacuum energy in an expanding
spacetime, we describe a non-singular cosmological model in which the vacuum
density decays with time, with a concomitant production of matter. During an
infinitely long period we have an empty, inflationary universe, with H \approx
1. This primordial era ends in a fast phase transition, during which H and
\Lambda decrease to nearly zero in a few Planck times, with release of a huge
amount of radiation. The late-time scenario is similar to the standard model,
with the radiation phase followed by a long dust era, which tends
asymptotically to a de Sitter universe, with vacuum dominating again. An
analysis of the redshift-distance relation for supernovas Ia leads to
cosmological parameters in agreement with other current estimations.Comment: Work presented at IRGAC 2006, Barcelona, July 11-15 2006. To appear
in a special issue of Journal of Physics
Inflation without Inflaton(s)
We propose a model for early universe cosmology without the need for
fundamental scalar fields. Cosmic acceleration and phenomenologically viable
reheating of the universe results from a series of energy transitions, where
during each transition vacuum energy is converted to thermal radiation. We show
that this `cascading universe' can lead to successful generation of adiabatic
density fluctuations and an observable gravity wave spectrum in some cases,
where in the simplest case it reproduces a spectrum similar to slow-roll models
of inflation. We also find the model provides a reasonable reheating
temperature after inflation ends. This type of model may also be relevant for
addressing the smallness of the vacuum energy today.Comment: 13 pages, 4 figures, published versio
Lambda polarization and single-spin left-right asymmetry in diffractive hadron-hadron collisions
We discuss Lambda polarization and single-spin left-right asymmetry in
diffractive hadron-hadron scattering at high energies. We show that the
physical picture proposed in a recent Letter is consistent with the
experimental observation that polarization in the diffractive
process, , is much higher than that in the inclusive
reaction, . We make predictions for the left-right asymmetry,
A_N, and for the spin transfer, , in the single-spin process
and suggest further experimental tests of the
proposed picture.Comment: 14 pages, 3 ps-figures. Phys. Rev. D (in press
Inaccessible Singularities in Toral Cosmology
The familiar Bang/Crunch singularities of classical cosmology have recently
been augmented by new varieties: rips, sudden singularities, and so on. These
tend to be associated with final states. Here we consider an alternative
possibility for the initial state: a singularity which has the novel property
of being inaccessible to physically well-defined probes. These singularities
arise naturally in cosmologies with toral spatial sections.Comment: 10 pages, version to appear in Classical and Quantum Gravit
Abnormal glycosylation in Joubert syndrome type 10.
BACKGROUND: The discovery of disease pathogenesis requires systematic agnostic screening of multiple homeostatic processes that may become deregulated. We illustrate this principle in the evaluation and diagnosis of a 5-year-old boy with Joubert syndrome type 10 (JBTS10). He carried the OFD1 mutation p.Gln886Lysfs*2 (NM_003611.2: c.2656del) and manifested features of Joubert syndrome.
METHODS: We integrated exome sequencing, MALDI-TOF mass spectrometry analyses of plasma and cultured dermal fibroblasts glycomes, and full clinical evaluation of the proband. Analyses of cilia formation and lectin staining were performed by immunofluorescence. Measurement of cellular nucleotide sugar levels was performed with high-performance anion-exchange chromatography with pulsed amperometric detection. Statistical analyses utilized the Student\u27s and Fisher\u27s exact t tests.
RESULTS: Glycome analyses of plasma and cultured dermal fibroblasts identified abnormal N- and O-linked glycosylation profiles. These findings replicated in two unrelated males with OFD1 mutations. Cultured fibroblasts from affected individuals had a defect in ciliogenesis. The proband\u27s fibroblasts also had an abnormally elevated nuclear sialylation signature and increased total cellular levels of CMP-sialic acid. Ciliogenesis and each glycosylation anomaly were rescued by expression of wild-type OFD1.
CONCLUSIONS: The rescue of ciliogenesis and glycosylation upon reintroduction of WT OFD1 suggests that both contribute to the pathogenesis of JBTS10
Towards the fabrication of phosphorus qubits for a silicon quantum computer
The quest to build a quantum computer has been inspired by the recognition of
the formidable computational power such a device could offer. In particular
silicon-based proposals, using the nuclear or electron spin of dopants as
qubits, are attractive due to the long spin relaxation times involved, their
scalability, and the ease of integration with existing silicon technology.
Fabrication of such devices however requires atomic scale manipulation - an
immense technological challenge. We demonstrate that it is possible to
fabricate an atomically-precise linear array of single phosphorus bearing
molecules on a silicon surface with the required dimensions for the fabrication
of a silicon-based quantum computer. We also discuss strategies for the
encapsulation of these phosphorus atoms by subsequent silicon crystal growth.Comment: To Appear in Phys. Rev. B Rapid Comm. 5 pages, 5 color figure
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