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Making Memories: Why Time Matters
In the last decade advances in human neuroscience have identified the critical importance of time in creating long-term memories. Circadian neuroscience has established biological time functions via cellular clocks regulated by photosensitive retinal ganglion cells and the suprachiasmatic nuclei. Individuals have different circadian clocks depending on their chronotypes that vary with genetic, age, and sex. In contrast, social time is determined by time zones, daylight savings time, and education and employment hours. Social time and circadian time differences can lead to circadian desynchronization, sleep deprivation, health problems, and poor cognitive performance. Synchronizing social time to circadian biology leads to better health and learning, as demonstrated in adolescent education. In-day making memories of complex bodies of structured information in education is organized in social time and uses many different learning techniques. Research in the neuroscience of long-term memory (LTM) has demonstrated in-day time spaced learning patterns of three repetitions of information separated by two rest periods are effective in making memories in mammals and humans. This time pattern is based on the intracellular processes required in synaptic plasticity. Circadian desynchronization, sleep deprivation, and memory consolidation in sleep are less well-understood, though there has been considerable progress in neuroscience research in the last decade. The interplay of circadian, in-day and sleep neuroscience research are creating an understanding of making memories in the first 24-h that has already led to interventions that can improve health and learning
Threshold Hadronic Event Shapes with Effective Field Theory
Hadronic event shapes, that is, event shapes at hadron colliders, could
provide a great way to test both standard and non-standard theoretical models.
However, they are significantly more complicated than event shapes at e+e-
colliders, involving multiple hard directions, multiple channels and multiple
color structures. In this paper, hadronic event shapes are examined with
Soft-Collinear Effective Theory (SCET) by expanding around the dijet limit. A
simple event shape, threshold thrust, is defined. This observable is global and
has no free parameters, making it ideal for clarifying how resummation of
hadronic event shapes can be done in SCET. Threshold thrust is calculated at
next-to-leading fixed order (NLO) in SCET and resummed to
next-to-next-to-leading logarithmic accuracy (NNLL). The scale-dependent parts
of the soft function are shown to agree with what is expected from general
observations, and the factorization formula is explicitly shown to be
renormalization group invariant to 1-loop. Although threshold thrust is not
itself expected to be phenomenologically interesting, it can be modified into a
related observable which allows the jet pT distribution to be calculated and
resummed to NNLL+NLO accuracy. As in other processes, one expects resummation
to be important even for moderate jet momenta due to dynamical threshold
enhancement. A general discussion of threshold enhancement and non-global logs
in hadronic event shapes is also included.Comment: 38 pages, 2 figures; small typos corrected in v
1-loop matching and NNLL resummation for all partonic 2 to 2 processes in QCD
The Wilson Coefficients for all 4-parton operators which arise in matching
QCD to Soft-Collinear Effective Theory (SCET) are computed at 1-loop. Any dijet
observable calculated in SCET beyond leading order will require these results.
The Wilson coefficients are separated by spin and color, although most
applications will involve only the spin-averaged hard functions. The anomalous
dimensions for the Wilson coefficients are given to 2-loop order, and the
renormalization group equations are solved explicitly. This will allow for
analytical resummation of dijet observables to next-to-next-to-leading
logarithmic accuracy. For each channel, there is a natural basis in which the
evolution is diagonal in color space. The same basis also diagonalizes the
color evolution for the soft function. Even though soft functions required for
SCET calculations are observable dependent, it is shown that their
renormalization group evolution is almost completely determined by a universal
structure. With these results, it will be possible to calculate hadronic event
shapes or other dijet observables to next-to-leading order with
next-to-next-to-leading log resummation.Comment: 28 pages, 5 tables; v2: typo corrected in Eq. (56
New phenomena in the standard no-scale supergravity model
We revisit the no-scale mechanism in the context of the simplest no-scale
supergravity extension of the Standard Model. This model has the usual
five-dimensional parameter space plus an additional parameter . We show how predictions of the model may be extracted over
the whole parameter space. A necessary condition for the potential to be stable
is , which is satisfied if \bf m_{3/2}\lsim2 m_{\tilde
q}. Order of magnitude calculations reveal a no-lose theorem guaranteeing
interesting and potentially observable new phenomena in the neutral scalar
sector of the theory which would constitute a ``smoking gun'' of the no-scale
mechanism. This new phenomenology is model-independent and divides into three
scenarios, depending on the ratio of the weak scale to the vev at the minimum
of the no-scale direction. We also calculate the residual vacuum energy at the
unification scale (), and find that in typical models one must
require . Such constraints should be important in the search for the
correct string no-scale supergravity model. We also show how specific classes
of string models fit within this framework.Comment: 11pages, LaTeX, 1 figure (included), CERN-TH.7433/9
Computer program to predict spacecraft window deformations and compute window induced angular deviations of light rays
Computer program for predicting spacecraft window deformations and computing window induced angular deviations of light ray
Convergence Rates for Newton’s Method at Singular Points
If Newton’s method is employed to find a root of a map from a Banach space into itself and the derivative is singular at that root, the convergence of the Newton iterates to the root is linear rather than quadratic. In this paper we give a detailed analysis of the linear convergence rates for several types of singular problems. For some of these problems we describe modifications of Newton’s method which will restore quadratic convergence
Evolution of basin and range structure in the Ruby Mountains and vicinity, Nevada
Results from various age dating techniques, seismic reflection profiling hydrocarbon maturation studies, and structural analysis were used to evaluate the Cenozoic deformation in the Ruby Mountains and adjoining ranges (pinyon Range and Cortez Range) in Elko and Eureka Counties, Nevada. Age dating techniques used include potassium-argon ages of biotites from granites published by Kistler et al. (1981) and fission track ages from apatite and zircon. Fission track ages from apatite reflect a closing temperature of 100 plus or minus 20 deg C. Zircon fission track ages reflect a closing temperature of 175 plus or minus 25 deg C and potassium-argon ages from brotite reflect a closing temperature of 250 plus or minus 30 deg C. Thus these results allow a reasonably precise tracking of the evolution of the ranges during the Cenozoic. Seismic reflection data are available from Huntington Valley. Access to seismic reflection data directly to the west of the Harrison Pass Pluton in the central Ruby Mountains was obtained. In addition results are available from several deep exploration holes in Huntington Valley
Conflicts in Production Planning and Control Systems
A wide variety of functions either comprise or interface with a Production Planning and Control (PPC) system. Some place demands on the system; some place constraints; some produce the the action; some monitor events and may initiate corrective demands; some monitor passively in order to compile records. Such a wide spectrum of interests normally results in conflicting demands being made on the PPC system, the satisfactory resolution of such conflicts and the design of an efficient system is at the same time difficult and vitally important.
This paper represents an attempt to clarify the scope of a normal PPC system, to structure its tasks and objectives, to outline the interfaces with other functions and activities, to to discuss some of the more obvious problems and to suggest the need for, and form of, some standards
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