1,160 research outputs found
Switched Control of Electron Nuclear Spin Systems
In this article, we study control of electron-nuclear spin dynamics at
magnetic field strengths where the Larmor frequency of the nucleus is
comparable to the hyperfine coupling strength. The quantization axis for the
nuclear spin differs from the static B_0 field direction and depends on the
state of the electron spin. The quantization axis can be switched by flipping
the state of electron spin, allowing for universal control on nuclear spin
states. We show that by performing a sequence of flips (each followed by a
suitable delay), we can perform any desired rotation on the nuclear spins,
which can also be conditioned on the state of the electron spin. These
operations, combined with electron spin rotations can be used to synthesize any
unitary transformation on the coupled electron-nuclear spin system. We discuss
how these methods can be used for design of experiments for transfer of
polarization from the electron to the nuclear spins
Detection of REM Sleep Behaviour Disorder by Automated Polysomnography Analysis
Evidence suggests Rapid-Eye-Movement (REM) Sleep Behaviour Disorder (RBD) is
an early predictor of Parkinson's disease. This study proposes a
fully-automated framework for RBD detection consisting of automated sleep
staging followed by RBD identification. Analysis was assessed using a limited
polysomnography montage from 53 participants with RBD and 53 age-matched
healthy controls. Sleep stage classification was achieved using a Random Forest
(RF) classifier and 156 features extracted from electroencephalogram (EEG),
electrooculogram (EOG) and electromyogram (EMG) channels. For RBD detection, a
RF classifier was trained combining established techniques to quantify muscle
atonia with additional features that incorporate sleep architecture and the EMG
fractal exponent. Automated multi-state sleep staging achieved a 0.62 Cohen's
Kappa score. RBD detection accuracy improved by 10% to 96% (compared to
individual established metrics) when using manually annotated sleep staging.
Accuracy remained high (92%) when using automated sleep staging. This study
outperforms established metrics and demonstrates that incorporating sleep
architecture and sleep stage transitions can benefit RBD detection. This study
also achieved automated sleep staging with a level of accuracy comparable to
manual annotation. This study validates a tractable, fully-automated, and
sensitive pipeline for RBD identification that could be translated to wearable
take-home technology.Comment: 20 pages, 3 figure
Threat and imposition of economic sanctions 1945–2005: Updating the TIES dataset
Recent research on economic sanctions has produced significant advances in our theoretical and empirical understanding of the causes and effects of these phenomena. Our theoretical understanding, which has been guided by empirical findings, has reached the point where existing data sets are no longer adequate to test important hypotheses. This article presents a recently updated version of the Threat and Imposition of Economic Sanctions (TIES) data set. This version of the data extends the temporal domain, corrects errors, updates cases that were ongoing as of the last release, and includes a few additional variables. We describe the dataset, paying special attention to the key differences in the new version, and we present descriptive statistics for some of the key variables, highlighting differences across versions. Since the major change in the data set was to more than double the time period covered, we also present some simple statistics showing trends in sanctions use over time
Spatially separating language masker from target results in spatial and linguistic masking release
Several studies demonstrate that in complex auditory scenes, speech recognition is improved when the competing background and target speech differ linguistically. However, such studies typically utilize spatially co-located speech sources which may not fully capture typical listening conditions. Furthermore, co-located presentation may overestimate the observed benefit of linguistic dissimilarity. The current study examines the effect of spatial separation on linguistic release from masking. Results demonstrate that linguistic release from masking does extend to spatially separated sources. The overall magnitude of the observed effect, however, appears to be diminished relative to the co-located presentation conditions
KNOWLEDGE AND HEALTH SEEKING BEHAVIOR RELATED TO KALA-AZAR IN RURAL COMMUNITIES OF EAST CHAMPARAN DISTRICT, BIHAR
Ă‚Â Ă‚Â Objective: To find out the sociodemographic characteristics, knowledge and health seeking behavior related to KA in the East Champaran district, Bihar among study subject.Methods: A case-control study was conducted to understand the knowledge and health seeking behavior related to KA in the East Champaran district. A total of 100 KA cases and 100 healthy controls selected from the neighborhoods of cases.Results: The knowledge of the population showed that the male constituted 58% of the total population in which 56% were case and 60% were control. Majority of the respondent 76.5% were aware from the KA. Maximum of the respondent 72.5% believed that biting time of sand flies were in the night. Moreover, 71% respondent cannot know how to protect the KA transmission.Conclusion: These results will be useful for further improvement in the KA control programs for intervention strategies. The knowledge of the study subject about KA, the vectors, the transmission of KA, and control measures was poor which needs some effort of the public health system by the Ministry working in the field of health
Constraining the Inflationary Equation of State
We explore possible constraints on the inflationary equation state: p=w\rho.
While w must be close to -1 for those modes that contribute to the observed
power spectrum, for those modes currently out of experimental reach, the
constraints on w are much weaker, with only w<-1/3 as an a priori requirement.
We find, however, that limits on the reheat temperature and the inflationary
energy scale constrain w further, though there is still ample parameter space
for a vastly different (accelerating) equation of state between the end of
quasi-de Sitter inflation and the beginning of the radiation-dominated era. In
the event that such an epoch of acceleration could be observed, we review the
consequences for the primordial power spectrum.Comment: 12 pages, 2 figur
Determinants of Sanctions Effectiveness: Sensitivity Analysis Using New Data
In the literature on sanctions effectiveness, scholars have identified
a number of factors that may contribute to sanctions success.
However, existing empirical studies provide mixed findings concerning
the effects of these factors. This research note explores
two possible reasons for this lack of consistency in the literature.
First, informed by the recent theories that suggest threats are an
important part of sanctions episodes, we analyze both threats and
imposed sanctions. Second, to lessen model dependency of empirical
findings, we employ a methodology that permits us to check
systematically the robustness of the empirical results under various
model specifications. Using the newly released Threat and
Imposition of Economic Sanctions data, our analyses of both
threats and imposed sanctions show that two factors—involvement
of international institutions and severe costs on target states—are
positively and robustly related to sanctions success at every stage
in sanctions episodes. Our analyses also identify a number of other
variables that are systematically related to sanctions success, but
the significance of these relationships depends on the specific model
estimated. Finally, our results point to a number of differences at
the threat and imposition stages, which suggests specific selection
effects that should be explored in future work
Effect of defects on thermal denaturation of DNA Oligomers
The effect of defects on the melting profile of short heterogeneous DNA
chains are calculated using the Peyrard-Bishop Hamiltonian. The on-site
potential on a defect site is represented by a potential which has only the
short-range repulsion and the flat part without well of the Morse potential.
The stacking energy between the two neigbouring pairs involving a defect site
is also modified. The results are found to be in good agreement with the
experiments.Comment: 11 pages including 5 postscript figure; To be appear in Phys. Rev.
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