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Comparing Experimental Phase Behavior of Ion-Doped Block Copolymers with Theoretical Predictions Based on Selective Ion Solvation
The effects of salt-doping on the morphological behavior of block copolymers are well established but remain poorly understood, partially because of the challenge of resolving electrostatics in a heterogeneous medium with low average permittivity. By employing a recently developed field theory, we analyze the phase behavior of polystyrene-b-poly(ethylene oxide) (SEO) copolymers doped with lithium bis(trifluoromethanesulfonyl)imide salts (LiTFSI). Using a single fitting parameter, the ionic solvation radius, we obtain qualitative agreement between our theory and experimental data over a range of polymer molecular weights and copolymer compositions. Such agreement supports and highlights the need of solvation free energy to accurately describe the self-assembly of ion-doped block copolymers and demonstrates that experimentally observed dependence on molecular weight, not present in neutral block copolymers, can be rationalized by solvation effects. Overall, morphological variations are stronger than those predicted by the leading, linear order theory but can be captured by the full model
An MRI Compatible Visual Force-Feedback System for the Study of Force Control Mechanics
Motor task experiments play an essential role in exploring the brain mechanisms of movement control, and visual force-feedback is an important factor in these motor experiments. In this paper, the authors proposed a visual force-feedback system suitable for neuroscience experiment. With this system, the force output produced by participants can be detected and recorded in real time, while force output was visually displayed as a feedback cue to the participants simultaneously. Furthermore, this force feedback system is MRI compatible, and can be used both in fMRI and ERP experiments. The proposed system has been applied in hand-grip tasks and finger movement experiments, which were designed to explore the relationship between force output and brain activation mode in normal subject and stroke patient. The results demonstrated that various force levels were well detected and visual feedback signals enabled the accomplishment of experiments with both fixed and variable target force levels
Uncertainty-weighted Multi-tasking for and T Mapping in the Liver with Self-supervised Learning
Multi-parametric mapping of MRI relaxations in liver has the potential of
revealing pathological information of the liver. A self-supervised learning
based multi-parametric mapping method is proposed to map T and T
simultaneously, by utilising the relaxation constraint in the learning process.
Data noise of different mapping tasks is utilised to make the model
uncertainty-aware, which adaptively weight different mapping tasks during
learning. The method was examined on a dataset of 51 patients with
non-alcoholic fatter liver disease. Results showed that the proposed method can
produce comparable parametric maps to the traditional multi-contrast pixel wise
fitting method, with a reduced number of images and less computation time. The
uncertainty weighting also improves the model performance. It has the potential
of accelerating MRI quantitative imaging
A fourth generation, anomalous like-sign dimuon charge asymmetry and the LHC
A fourth chiral generation, with in the range GeV and a moderate value of the CP-violating phase can explain the
anomalous like-sign dimuon charge asymmetry observed recently by the D0
collaboration. The required parameters are found to be consistent with
constraints from other and decays. The presence of such quarks, apart
from being detectable in the early stages of the LHC, would also have important
consequences in the electroweak symmetry breaking sector.Comment: 18 pages, 9 figures, Figure 1 is modified, more discussions are added
in section 2. new references adde
Hadamard Kernel SVM: Applications for Breast Cancer Outcome Predictions
16th International Conference on Bioinformatics (InCoB 2017): Systems Biologypublished_or_final_versio
Subfamily specific conservation profiles for proteins based on n-gram patterns
<p>Abstract</p> <p>Background</p> <p>A new algorithm has been developed for generating conservation profiles that reflect the evolutionary history of the subfamily associated with a query sequence. It is based on n-gram patterns (NP{<it>n,m</it>}) which are sets of <it>n </it>residues and <it>m </it>wildcards in windows of size <it>n+m</it>. The generation of conservation profiles is treated as a signal-to-noise problem where the signal is the count of n-gram patterns in target sequences that are similar to the query sequence and the noise is the count over all target sequences. The signal is differentiated from the noise by applying singular value decomposition to sets of target sequences rank ordered by similarity with respect to the query.</p> <p>Results</p> <p>The new algorithm was used to construct 4,248 profiles from 120 randomly selected Pfam-A families. These were compared to profiles generated from multiple alignments using the consensus approach. The two profiles were similar whenever the subfamily associated with the query sequence was well represented in the multiple alignment. It was possible to construct subfamily specific conservation profiles using the new algorithm for subfamilies with as few as five members. The speed of the new algorithm was comparable to the multiple alignment approach.</p> <p>Conclusion</p> <p>Subfamily specific conservation profiles can be generated by the new algorithm without aprioi knowledge of family relationships or domain architecture. This is useful when the subfamily contains multiple domains with different levels of representation in protein databases. It may also be applicable when the subfamily sample size is too small for the multiple alignment approach.</p
Simultaneous Extraction of the Fermi constant and PMNS matrix elements in the presence of a fourth generation
Several recent studies performed on constraints of a fourth generation of
quarks and leptons suffer from the ad-hoc assumption that 3 x 3 unitarity holds
for the first three generations in the neutrino sector. Only under this
assumption one is able to determine the Fermi constant G_F from the muon
lifetime measurement with the claimed precision of G_F = 1.16637 (1) x 10^-5
GeV^-2. We study how well G_F can be extracted within the framework of four
generations from leptonic and radiative mu and tau decays, as well as from K_l3
decays and leptonic decays of charged pions, and we discuss the role of lepton
universality tests in this context. We emphasize that constraints on a fourth
generation from quark and lepton flavour observables and from electroweak
precision observables can only be obtained in a consistent way if these three
sectors are considered simultaneously. In the combined fit to leptonic and
radiative mu and tau decays, K_l3 decays and leptonic decays of charged pions
we find a p-value of 2.6% for the fourth generation matrix element |U_{e 4}|=0
of the neutrino mixing matrix.Comment: 19 pages, 3 figures with 16 subfigures, references and text added
refering to earlier related work, figures and text in discussion section
added, results and conclusions unchange
Effects of osteoprotegerin from transfection of pcDNA3.1(+)/chOPG on bioactivity of chicken osteoclasts
Study of the Baryon-Antibaryon Low-Mass Enhancements in Charmless Three-body Baryonic B Decays
The angular distributions of the baryon-antibaryon low-mass enhancements seen
in the charmless three-body baryonic B decays B+ -> p pbar K+, B0 -> p pbar Ks,
and B0 -> p Lambdabar pi- are reported. A quark fragmentation interpretation is
supported, while the gluonic resonance picture is disfavored. Searches for the
Theta+ and Theta++ pentaquarks in the relevant decay modes and possible
glueball states G with 2.2 GeV/c2 < M-ppbar < 2.4 GeV/c2 in the ppbar systems
give null results. We set upper limits on the products of branching fractions,
B(B0 -> Theta+ p)\times B(Theta+ -> p Ks) Theta++
pbar) \times B(Theta++ -> p K+) G K+) \times
B(G -> p pbar) < 4.1 \times 10^{-7} at the 90% confidence level. The analysis
is based on a 140 fb^{-1} data sample recorded on the Upsilon(4S) resonance
with the Belle detector at the KEKB asymmetric-energy e+e- collider.Comment: 14 pages, 13 figure files, update of hep-ex/0409010 for journal
submisssio
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