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Theorizing Reactive Reflexivity: Lifestyle Displacement and Discordant Performances of Taste
Culturally oriented consumer research has predominantly been framed by two ideal types of reflexivity, which we characterize as existential and critical reflexivity. Drawing from our research on divorced women who have been displaced from their domestically oriented, middle-class lifestyles, we develop an alternative conceptualization—reactive reflexivity—that highlights a different relationship among consumer agency, social structures, and identity goals and practices. Rather than embracing their post-divorce lifestyles as a revitalizing challenge (per existential reflexivity) or liberation from a constraining gender role (per critical reflexivity), our participants felt estranged from their current lifestyle and reflexively viewed their pre-divorce lifestyle as a structure of relative empowerment that had afforded emotional, aesthetic, and status-oriented benefits. In reflexive response to these perceived lifestyle discontinuities, they engaged in discordant practices of taste that sought to insulate their aesthetic predispositions from structurally imposed socioeconomic constraints and, ultimately, to accomplish a reactive identity goal of regaining their displaced status as middle-class homemakers. We discuss the implications of our analysis for theorizations of consumer taste and the relationships between gender ideologies and reflexive consumption practices
HAPTEN-SANDWICH LABELING : I. A GENERAL PROCEDURE FOR SIMULTANEOUS LABELING OF MULTIPLE CELL SURFACE ANTIGENS FOR FLUORESCENCE AND ELECTRON MICROSCOPY
A hapten-sandwich procedure has been developed for specific labeling of cell surface antigens for fluorescence or electron microscopy. Haptens are azo-coupled to immunoglobulins specific for a cell surface antigen; the hapten-modified cell-bound antibodies can then be visualized by adding fluorescent antihapten antibody, or by adding antihapten antibody followed by hapten-modified markers for electron microscopy. Virus or high molecular weight protein markers are lightly cross-linked before conjugation with hapten to prevent their disruption. Such stable hapten-modified markers, and the accessibility of many different purified anti-azophenyl-hapten antibodies, make it feasible to distinguish more than one membrane antigen in a given labeling experiment. When mouse lymphoid cell populations are labeled with separate markers for Ig and for thymus-associated antigens, many cells exhibit the Ig marker exclusively or the thymic marker predominantly, and some cells are completely free of label
Exploring Model Complexity in Machine Learned Potentials for Simulated Properties
Machine learning (ML) enables the development of interatomic potentials that
promise the accuracy of first principles methods while retaining the low cost
and parallel efficiency of empirical potentials. While ML potentials
traditionally use atom-centered descriptors as inputs, different models such as
linear regression and neural networks can map these descriptors to atomic
energies and forces. This begs the question: what is the improvement in
accuracy due to model complexity irrespective of choice of descriptors? We
curate three datasets to investigate this question in terms of ab initio energy
and force errors: (1) solid and liquid silicon, (2) gallium nitride, and (3)
the superionic conductor LGPS. We further investigate how these errors affect
simulated properties with these models and verify if the improvement in fitting
errors corresponds to measurable improvement in property prediction. Since
linear and nonlinear regression models have different advantages and
disadvantages, the results presented herein help researchers choose models for
their particular application. By assessing different models, we observe
correlations between fitting quantity (e.g. atomic force) error and simulated
property error with respect to ab initio values. Such observations can be
repeated by other researchers to determine the level of accuracy, and hence
model complexity, needed for their particular systems of interest
Key Residues Defining the Μ-Opioid Receptor Binding Pocket: A Site-Directed Mutagenesis Study
Structural elements of the rat Μ-opioid receptor important in ligand receptor binding and selectivity were examined using a site-directed mutagenesis approach. Five single amino acid mutations were made, three that altered conserved residues in the Μ, Δ, and Κ receptors (Asn 150 to Ala, His 297 to Ala, and Tyr 326 to Phe) and two designed to test for Μ/Δ selectivity (Ile 198 to Val and Val 202 to Ile). Mutation of His 297 in transmembrane domain 6 (TM6) resulted in no detectable binding with [ 3 H]DAMGO ( 3 H-labeled d-Ala 2 , N -Me-Phe 4 ,Gly-ol 5 -enkephalin), [ 3 H]bremazocine, or [ 3 H]ethylketocyclazocine. Mutation of Asn 150 in TM3 produces a three- to 20-fold increase in affinity for the opioid agonists morphine, DAMGO, fentanyl, Β-endorphin 1–31 , JOM-13, deltorphin II, dynorphin 1–13 , and U50,488, with no change in the binding of antagonists such as naloxone, naltrexone, naltrindole, and nor-binaltorphamine. In contrast, the Tyr 326 mutation in TM7 resulted in a decreased affinity for a wide spectrum of Μ, Δ, and Κ agonists and antagonists. Altering Val 202 to Ile in TM4 produced no change on ligand affinity, but Ile 198 to Val resulted in a four- to fivefold decreased affinity for the Μ agonists morphine and DAMGO, with no change in the binding affinities of Κ and Δ ligands.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65474/1/j.1471-4159.1997.68010344.x.pd
Local models of stellar convection: Reynolds stresses and turbulent heat transport
We study stellar convection using a local three-dimensional MHD model, with
which we investigate the influence of rotation and large-scale magnetic fields
on the turbulent momentum and heat transport. The former is studied by
computing the Reynolds stresses, the latter by calculating the correlation of
velocity and temperature fluctuations, both as functions of rotation and
latitude. We find that the horisontal correlation, Q_(theta phi), capable of
generating horisontal differential rotation, is mostly negative in the southern
hemisphere for Coriolis numbers exceeding unity, corresponding to equatorward
flux of angular momentum in accordance with solar observations. The radial
component Q_(r phi) is negative for slow and intermediate rotation indicating
inward transport of angular momentum, while for rapid rotation, the transport
occurs outwards. Parametrisation in terms of the mean-field Lambda-effect shows
qualitative agreement with the turbulence model of Kichatinov & R\"udiger
(1993) for the horisontal part H \propto Q_(theta phi)/cos(theta), whereas for
the vertical part, V \propto Q_(r phi)/sin(theta), agreement only for
intermediate rotation exists. The Lambda-coefficients become suppressed in the
limit of rapid rotation, this rotational quenching being stronger for the V
component than for H. We find that the stresses are enhanced by the presence of
the magnetic field for field strengths up to and above the equipartition value,
without significant quenching. Concerning the turbulent heat transport, our
calculations show that the transport in the radial direction is most efficient
at the equatorial regions, obtains a minimum at midlatitudes, and shows a
slight increase towards the poles. The latitudinal heat transport does not show
a systematic trend as function of latitude or rotation.Comment: 26 pages, 20 figures, final published version. For a version with
higher resolution figures, see http://cc.oulu.fi/~pkapyla/publ.htm
Lower bounds on the complexity of simulating quantum gates
We give a simple proof of a formula for the minimal time required to simulate
a two-qubit unitary operation using a fixed two-qubit Hamiltonian together with
fast local unitaries. We also note that a related lower bound holds for
arbitrary n-qubit gates.Comment: 6 page
Risk stratification by pre-operative cardiopulmonary exercise testing improves outcomes following elective abdominal aortic aneurysm surgery : a cohort study
Background:
In 2009, the NHS evidence adoption center and National Institute for Health and Care Excellence (NICE) published a review of the use of endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms (AAAs). They recommended the development of a risk-assessment tool to help identify AAA patients with greater or lesser risk of operative mortality and to contribute to mortality prediction.
A low anaerobic threshold (AT), which is a reliable, objective measure of pre-operative cardiorespiratory fitness, as determined by pre-operative cardiopulmonary exercise testing (CPET) is associated with poor surgical outcomes for major abdominal surgery. We aimed to assess the impact of a CPET-based risk-stratification strategy upon perioperative mortality, length of stay and non-operative costs for elective (open and endovascular) infra-renal AAA patients.
Methods:
A retrospective cohort study was undertaken. Pre-operative CPET-based selection for elective surgical intervention was introduced in 2007. An anonymized cohort of 230 consecutive infra-renal AAA patients (2007 to 2011) was studied. A historical control group of 128 consecutive infra-renal AAA patients (2003 to 2007) was identified for comparison.
Comparative analysis of demographic and outcome data for CPET-pass (AT ≥ 11 ml/kg/min), CPET-fail (AT < 11 ml/kg/min) and CPET-submaximal (no AT generated) subgroups with control subjects was performed. Primary outcomes included 30-day mortality, survival and length of stay (LOS); secondary outcomes were non-operative inpatient costs.
Results:
Of 230 subjects, 188 underwent CPET: CPET-pass n = 131, CPET-fail n = 35 and CPET-submaximal n = 22. When compared to the controls, CPET-pass patients exhibited reduced median total LOS (10 vs 13 days for open surgery, n = 74, P < 0.01 and 4 vs 6 days for EVAR, n = 29, P < 0.05), intensive therapy unit requirement (3 vs 4 days for open repair only, P < 0.001), non-operative costs (£5,387 vs £9,634 for open repair, P < 0.001) and perioperative mortality (2.7% vs 12.6% (odds ratio: 0.19) for open repair only, P < 0.05). CPET-stratified (open/endovascular) patients exhibited a mid-term survival benefit (P < 0.05).
Conclusion:
In this retrospective cohort study, a pre-operative AT > 11 ml/kg/min was associated with reduced perioperative mortality (open cases only), LOS, survival and inpatient costs (open and endovascular repair) for elective infra-renal AAA surgery
Spectroscopy of luminous z>7 galaxy candidates and sources of contamination in z>7 galaxy searches
We present three bright z+ dropout candidates selected from deep
Near-Infrared (NIR) imaging of the COSMOS 2 square degree field. All three
objects match the 0.8-8um colors of other published z>7 candidates but are
three magnitudes brighter, facilitating further study. Deep spectroscopy of two
of the candidates covering 0.64-1.02um with Keck-DEIMOS and all three covering
0.94-1.10um and 1.52-1.80um with Keck-NIRSPEC detects weak spectral features
tentatively identified as Ly-alpha at z=6.95 and z=7.69 in two of the objects.
The third object is placed at z~1.6 based on a 24um and weak optical detection.
A comparison with the spectral energy distributions of known z<7 galaxies,
including objects with strong spectral lines, large extinction, and large
systematic uncertainties in the photometry yields no objects with similar
colors. However, the lambda>1um properties of all three objects can be matched
to optically detected sources with photometric redshifts at z~1.8, so the
non-detection in the i+ and z+ bands are the primary factors which favors a z>7
solution. If any of these objects are at z~7 the bright end of the luminosity
function is significantly higher at z>7 than suggested by previous studies, but
consistent within the statistical uncertainty and the dark matter halo
distribution. If these objects are at low redshift, the Lyman-Break selection
must be contaminated by a previously unknown population of low redshift objects
with very strong breaks in their broad band spectral energy distributions and
blue NIR colors. The implications of this result on luminosity function
evolution at high redshift is discussed. We show that the primary limitation of
z>7 galaxy searches with broad filters is the depth of the available optical
data.Comment: 15 Pages, 15 figures, accepted to Ap
Surprising variations in the rotation of the chemically peculiar stars CU Virginis and V901 Orionis
CU Vir and V901 Ori belong among these few magnetic chemically peculiar stars
whose rotation periods vary on timescales of decades. We aim to study the
stability of the periods in CU Vir and V901 Ori using all accessible
observational data containing phase information. We collected all available
relevant archived observations supplemented with our new measurements of these
stars and analysed the period variations of the stars using a novel method that
allows for the combination of data of diverse sorts. We found that the shapes
of their phase curves were constant, while the periods were changing. Both
stars exhibit alternating intervals of rotational braking and acceleration. The
rotation period of CU Vir was gradually shortening until the year 1968, when it
reached its local minimum of 0.52067198 d. The period then started increasing,
reaching its local maximum of 0.5207163 d in the year 2005. Since that time the
rotation has begun to accelerate again. We also found much smaller period
changes in CU Vir on a timescale of several years. The rotation period of V901
Ori was increasing for the past quarter-century, reaching a maximum of 1.538771
d in the year 2003, when the rotation period began to decrease. A theoretically
unexpected alternating variability of rotation periods in these stars would
remove the spin-down time paradox and brings a new insight into structure and
evolution of magnetic upper-main-sequence stars.Comment: 5 pages, 3 figure
Transgenic Rescue of the LARGEmyd Mouse: A LARGE Therapeutic Window?
LARGE is a glycosyltransferase involved in glycosylation of α-dystroglycan (α-DG). Absence of this protein in the LARGEmyd mouse results in α-DG hypoglycosylation, and is associated with central nervous system abnormalities and progressive muscular dystrophy. Up-regulation of LARGE has previously been proposed as a therapy for the secondary dystroglycanopathies: overexpression in cells compensates for defects in multiple dystroglycanopathy genes. Counterintuitively, LARGE overexpression in an FKRP-deficient mouse exacerbates pathology, suggesting that modulation of α-DG glycosylation requires further investigation. Here we demonstrate that transgenic expression of human LARGE (LARGE-LV5) in the LARGEmyd mouse restores α-DG glycosylation (with marked hyperglycosylation in muscle) and that this corrects both the muscle pathology and brain architecture. By quantitative analyses of LARGE transcripts we also here show that levels of transgenic and endogenous LARGE in the brains of transgenic animals are comparable, but that the transgene is markedly overexpressed in heart and particularly skeletal muscle (20–100 fold over endogenous). Our data suggest LARGE overexpression may only be deleterious under a forced regenerative context, such as that resulting from a reduction in FKRP: in the absence of such a defect we show that systemic expression of LARGE can indeed act therapeutically, and that even dramatic LARGE overexpression is well-tolerated in heart and skeletal muscle. Moreover, correction of LARGEmyd brain pathology with only moderate, near-physiological LARGE expression suggests a generous therapeutic window
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