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Older female mice lacking triggering recepter expressed on myeloid cells-2 have worse post-stroke neurological function and enhanced pro-inflammatory responses
Modulated sparse superposition codes for the complex AWGN channel
This paper studies a generalization of sparse superposition codes (SPARCs)
for communication over the complex additive white Gaussian noise (AWGN)
channel. In a SPARC, the codebook is defined in terms of a design matrix, and
each codeword is a generated by multiplying the design matrix with a sparse
message vector. In the standard SPARC construction, information is encoded in
the locations of the non-zero entries of the message vector. In this paper we
generalize the construction and consider modulated SPARCs, where information in
encoded in both the locations and the values of the non-zero entries of the
message vector. We focus on the case where the non-zero entries take values
from a phase-shift keying (PSK) constellation. We propose a computationally
efficient approximate message passing (AMP) decoder, and obtain analytical
bounds on the state evolution parameters which predict the error performance of
the decoder. Using these bounds we show that PSK-modulated SPARCs are
asymptotically capacity achieving for the complex AWGN channel, with either
spatial coupling or power allocation. We also provide numerical simulation
results to demonstrate the error performance at finite code lengths. These
results show that introducing modulation to the SPARC design can significantly
reduce decoding complexity without sacrificing error performance
Toeplitz Inverse Covariance-Based Clustering of Multivariate Time Series Data
Subsequence clustering of multivariate time series is a useful tool for
discovering repeated patterns in temporal data. Once these patterns have been
discovered, seemingly complicated datasets can be interpreted as a temporal
sequence of only a small number of states, or clusters. For example, raw sensor
data from a fitness-tracking application can be expressed as a timeline of a
select few actions (i.e., walking, sitting, running). However, discovering
these patterns is challenging because it requires simultaneous segmentation and
clustering of the time series. Furthermore, interpreting the resulting clusters
is difficult, especially when the data is high-dimensional. Here we propose a
new method of model-based clustering, which we call Toeplitz Inverse
Covariance-based Clustering (TICC). Each cluster in the TICC method is defined
by a correlation network, or Markov random field (MRF), characterizing the
interdependencies between different observations in a typical subsequence of
that cluster. Based on this graphical representation, TICC simultaneously
segments and clusters the time series data. We solve the TICC problem through
alternating minimization, using a variation of the expectation maximization
(EM) algorithm. We derive closed-form solutions to efficiently solve the two
resulting subproblems in a scalable way, through dynamic programming and the
alternating direction method of multipliers (ADMM), respectively. We validate
our approach by comparing TICC to several state-of-the-art baselines in a
series of synthetic experiments, and we then demonstrate on an automobile
sensor dataset how TICC can be used to learn interpretable clusters in
real-world scenarios.Comment: This revised version fixes two small typos in the published versio
Combustion of LOX with H2(sub g) under subcritical, critical, and supercritical conditions (Task 1) and experimental observation of dense spray and mixing of impinging jets (Task 2)
The objective was to achieve a better understanding of the combustion processes of liquid oxygen and gaseous hydrogen under broad range of pressure covering subcritical, critical, and supercritical conditions. The scope of the experimental work falls into the following areas: (1) design of the overall experimental setup; (2) modification of an existing windowed high pressure chamber; (3) design of the LOX feeding system; (4) provision of the safety features in the test rig design; (5) LOX cleanliness requirements; (6) cold shock testing; (7) implementation of data acquisition systems; (8) preliminary tests for system checkout; (9) modification of LOX feeding system; and (10) evaporation tests. Progress in each area is discussed
The quantum dynamic capacity formula of a quantum channel
The dynamic capacity theorem characterizes the reliable communication rates
of a quantum channel when combined with the noiseless resources of classical
communication, quantum communication, and entanglement. In prior work, we
proved the converse part of this theorem by making contact with many previous
results in the quantum Shannon theory literature. In this work, we prove the
theorem with an "ab initio" approach, using only the most basic tools in the
quantum information theorist's toolkit: the Alicki-Fannes' inequality, the
chain rule for quantum mutual information, elementary properties of quantum
entropy, and the quantum data processing inequality. The result is a simplified
proof of the theorem that should be more accessible to those unfamiliar with
the quantum Shannon theory literature. We also demonstrate that the "quantum
dynamic capacity formula" characterizes the Pareto optimal trade-off surface
for the full dynamic capacity region. Additivity of this formula simplifies the
computation of the trade-off surface, and we prove that its additivity holds
for the quantum Hadamard channels and the quantum erasure channel. We then
determine exact expressions for and plot the dynamic capacity region of the
quantum dephasing channel, an example from the Hadamard class, and the quantum
erasure channel.Comment: 24 pages, 3 figures; v2 has improved structure and minor corrections;
v3 has correction regarding the optimizatio
The role of skin trauma in the distribution of morphea lesions: A cross-sectional survey of the Morphea in Adults and Children cohort IV
Background: Skin trauma may play a role in the development of morphea lesions. The association between trauma and the distribution of cutaneous lesions has never been examined to our knowledge. Objective: We sought to determine whether patients enrolled in the Morphea in Adults and Children (MAC) cohort exhibit skin lesions distributed in areas of prior (isotopic) or ongoing (isomorphic) trauma. Methods: This was a cross-sectional analysis of the MAC cohort. Results: Of 329 patients in the MAC cohort, 52 (16%) had trauma-associated lesions at the onset of disease. Patients with lesions in an isotopic distribution had greater clinical severity as measured by a clinical outcome measure (mean modified Rodnan Skin Score of 13.8 vs 5.3, P = .004, 95% confidence interval 3.08-13.92) and impact on life quality (mean Dermatology Life Quality Index score 8.4 vs 4.1, P = .009, 95% confidence interval 1.18-7.50) than those with an isomorphic distribution. Most frequent associated traumas were chronic friction (isomorphic) and surgery/isotopic. Limitations: Recall bias for patient-reported events is a limitation. Conclusion: Of patients in the MAC cohort, 16% developed initial morphea lesions at sites of skin trauma. If these findings can be confirmed in additional series, they suggest that elective procedures and excessive skin trauma or friction might be avoided in these patients
A topological insulator surface under strong Coulomb, magnetic and disorder perturbations
Three dimensional topological insulators embody a newly discovered state of
matter characterized by conducting spin-momentum locked surface states that
span the bulk band gap as demonstrated via spin-resolved ARPES measurements .
This highly unusual surface environment provides a rich ground for the
discovery of novel physical phenomena. Here we present the first controlled
study of the topological insulator surfaces under strong Coulomb, magnetic and
disorder perturbations. We have used interaction of iron, with a large Coulomb
state and significant magnetic moment as a probe to \textit{systematically test
the robustness} of the topological surface states of the model topological
insulator BiSe. We observe that strong perturbation leads to the
creation of odd multiples of Dirac fermions and that magnetic interactions
break time reversal symmetry in the presence of band hybridization. We also
present a theoretical model to account for the altered surface of BiSe.
Taken collectively, these results are a critical guide in manipulating
topological surfaces for probing fundamental physics or developing device
applications.Comment: 14 pages, 4 Figures. arXiv admin note: substantial text overlap with
arXiv:1009.621
Perturbation Calculation of the Axial Anomaly of a Ginsparg-Wilson lattice Dirac operator
A recent proposal suggests that even if a Ginsparg-Wilson lattice Dirac
operator does not possess any topological zero modes in
topologically-nontrivial gauge backgrounds, it can reproduce correct axial
anomaly for sufficiently smooth gauge configurations, provided that it is
exponentially-local, doublers-free, and has correct continuum behavior. In this
paper, we calculate the axial anomaly of this lattice Dirac operator in weak
coupling perturbation theory, and show that it recovers the topological charge
density in the continuum limit.Comment: 25 pages, v2: calculation up to O(g^4) for nonabelian gauge
backgroun
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