94 research outputs found
Agreement of Cerebral State Index and Glasgow Coma Scale in Brain-Injured Patients
Background: Variables derived from electroencephalogram like cerebral state index (CSI) have been used to monitor the anesthesia depth during general anesthesia. Observed evidences show such variables have also been used as a detector of brain death or outcome predictor in traumatic brain-injured (TBI) patients.
Objectives: The current study was designed to determine the correlation between Glasgow coma score (GCS) and CSI among TBI patients.
Patients and Methods: In 60 brain-injured patients who did not need and receive sedatives, GCS and CSI were daily measured during the first ten days of their hospital stay. Correlation between GCS and CSI was studied using the Pearson's correlation test. The Gamma agreement coefficient was also calculated between the two variables for the first day of hospitalization.
Results: A significant correlation coefficient of 0.611-0.796 was observed between CSI and GCS in a ten-day period of the study (P < 0.001). Gamma agreement coefficient was 0.79 ( P < 0.001) for CSI and GCS for the first day of hospitalization. An increased daily correlation was observed in both CSI and GCS values. However, this increase was less significant in CSI compared with the GCS.
Conclusions: A statistically significant correlation and agreement was found between GCS and CSI in the brain-injured patients and GCS was also found to be more consistent and reliable compared with CSI
Epidemiology of Home-Related Injuries During a Six-Year Period in Kashan, Iran
Background: Injury is one of the leading causes of morbidity and mortality in the world, and the home is one of the most common places for these types of injuries.
Objectives: This study is designed to investigate the epidemiology of home-related injuries in Kashan, Iran.
Patients and Methods: This investigation is a retrospective cross-sectional study on existing data from the data bank of the Trauma Research Center at Kashan University of Medical Sciences during a six-year period. Demographic data such as; sex, age, place of residence, educational and occupational status, injury mechanism, injured organs and injury outcomes, were analyzed using a chi-squared test and P < 0.05 was considered significant.
Results: The number of home injuries was 10146 in total, that included about 25.2% of all injuries in Kashan City. Most of the injured people were men (58.3%), 87.4% lived in the city and 18.6% were aged more than 64 years. The majority (42.7%) had a primary or secondary school education and 27.2% were housewives. Falling from a height was the most common cause of injury (55.3%). Limbs were the most common body region that was injured (73.7%). Young men (under 15 years) and older women (over 65 years) had more injuries, especially from falls. There was a statistically significant difference between the sex and age of the injured people (P < 0.001), sex and injury mechanism (P < 0.001), and also between the injury mechanism and sex in the age groups (P < 0.001).
Conclusions: The most common injury mechanism in regard to home accidents was falls; therefore fall-related injury prevention programs should be designed to make homes safer and education should focus on changes in lifestyle to reduce fall susceptibility
Popular matchings in the marriage and roommates problems
Popular matchings have recently been a subject of study in the context of the so-called House Allocation Problem, where the objective is to match applicants to houses over which the applicants have preferences. A matching M is called popular if there is no other matching M′ with the property that more applicants prefer their allocation in M′ to their allocation in M. In this paper we study popular matchings in the context of the Roommates Problem, including its special (bipartite) case, the Marriage Problem. We investigate the relationship between popularity and stability, and describe efficient algorithms to test a matching for popularity in these settings. We also show that, when ties are permitted in the preferences, it is NP-hard to determine whether a popular matching exists in both the Roommates and Marriage cases
MAPK and JAK/STAT pathways targeted by miR-23a and miR-23b in prostate cancer: computational and in vitro approaches
The long-lasting inadequacy of existing treatments for prostate cancer has led to increasing efforts for developing novel therapies for this disease. MicroRNAs (miRNAs) are believed to have considerable therapeutic potential due to their role in regulating gene expression and cellular pathways. Identifying miRNAs that efficiently target genes and pathways is a key step in using these molecules for therapeutic purposes. Moreover, computational methods have been devised to help identify candidate miRNAs for each gene/pathway. MAPK and JAK/STAT pathways are known to have essential roles in cell proliferation and neoplastic transformation in different cancers including prostate cancer. Herein, we tried to identify miRNAs that target these pathways in the context of prostate cancer as therapeutic molecules. Genes involved in these pathways were analyzed with various algorithms to identify potentially targeting miRNAs. miR-23a and miR-23b were then selected as the best potential candidates that target a higher number of genes in these pathways with greater predictive scores. We then analyzed the expression of candidate miRNAs in LNCAP and PC3 cell lines as well as prostate cancer clinical samples. miR-23a and miR-23b showed a significant downregulation in cell line and tissue samples, a finding which is consistent with overactivation of these pathways in prostate cancer. In addition, we overexpressed miR-23a and miR-23b in LNCAP and PC3 cell lines, and these two miRNAs decreased IL-6R expression which has a critical role in these pathways. These results suggest the probability of utilizing miR-23a and miR-23b as therapeutic targets for the treatment of prostate cancer. © 2015, International Society of Oncology and BioMarkers (ISOBM)
Investigating a Class of Chessboard Density Matrices via Linear and Non-linear Entanglement Witnesses Constructed by Exact Convex Optimization
Here we consider a class of chessboard density matrices
starting with three-qubit ones which have positive partial transposes with
respect to all subsystems. To investigate the entanglement of these density
matrices, we use the entanglement witness approach. For constructing
entanglement witnesses (EWs) detecting these density matrices, we attempt to
convert the problem to an exact convex optimization problem. To this aim, we
map the convex set of separable states into a convex region, named feasible
region, and consider cases that the exact geometrical shape of feasible region
can be obtained. In this way, various linear and non-linear EWs are
constructed. The optimality and decomposability of some of introduced EWs are
also considered. Furthermore, the detection of the density matrices by
introduced EWs are discussed analytically and numerically.
{\bf Keywords: chessboard density matrices, optimal non-linear entanglement
witnesses, convex optimization}
{\bf PACs Index: 03.65.Ud}Comment: 35 pages, 1 figure
Quantum discord evolution of three-qubit states under noisy channels
We investigated the dissipative dynamics of quantum discord for correlated
qubits under Markovian environments.
The basic idea in the present scheme is that quantum discord is more general,
and possibly more robust and fundamental, than entanglement. We provide three
initially correlated qubits in pure Greenberger-Horne-Zeilinger (GHZ) or W
state and analyse the time evolution of the quantum discord under various
dissipative channels such as:
Pauli channels , , and , as well as
depolarising channels. Surprisingly, we find that under the action of Pauli
channel , the quantum discord of GHZ state is not affected by
decoherence. For the remaining dissipative channels, the W state is more robust
than the GHZ state against decoherence. Moreover, we compare the dynamics of
entanglement with that of the quantum discord under the conditions in which
disentanglement occurs and show that quantum discord is more robust than
entanglement except for phase flip coupling of the three qubits system to the
environment.Comment: 17 pages, 4 figures, accepted for publication in EPJ
Correlation dynamics of three spin under a classical dephasing environment
By starting from the stochastic Hamiltonian of the three correlated spins and
modeling their frequency fluctuations as caused by dephasing noisy environments
described by Ornstein-Uhlenbeck processes, we study the dynamics of quantum
correlations, including entanglement and quantum discord. We prepared initially
our open system with Greenberger-Horne-Zeilinger or W state and present the
exact solutions for evolution dynamics of entanglement and quantum discord
between three spins under both Markovian and non-Markovian regime of this
classical noise. By comparison the dynamics of entanglement with that of
quantum discord we find that entanglement can be more robust than quantum
discord against this noise. It is shown that by considering non-Markovian
extensions the survival time of correlations prolong.Comment: 13 pages, 4 figure
Dynamics of multipartite quantum correlations under decoherence
Quantum discord is an optimal resource for the quantification of classical
and non-classical correlations as compared to other related measures. Geometric
measure of quantum discord is another measure of quantum correlations.
Recently, the geometric quantum discord for multipartite states has been
introduced by Jianwei Xu [arxiv:quant/ph.1205.0330]. Motivated from the recent
study [Ann. Phys. 327 (2012) 851] for the bipartite systems, I have
investigated global quantum discord (QD) and geometric quantum discord (GQD)
under the influence of external environments for different multipartite states.
Werner-GHZ type three-qubit and six-qubit states are considered in inertial and
non-inertial settings. The dynamics of QD and GQD is investigated under
amplitude damping, phase damping, depolarizing and flipping channels. It is
seen that the quantum discord vanishes for p>0.75 in case of three-qubit GHZ
states and for p>0.5 for six qubit GHZ states. This implies that multipartite
states are more fragile to decoherence for higher values of N. Surprisingly, a
rapid sudden death of discord occurs in case of phase flip channel. However,
for bit flip channel, no sudden death happens for the six-qubit states. On the
other hand, depolarizing channel heavily influences the QD and GQD as compared
to the amplitude damping channel. It means that the depolarizing channel has
the most destructive influence on the discords for multipartite states. From
the perspective of accelerated observers, it is seen that effect of environment
on QD and GQD is much stronger than that of the acceleration of non-inertial
frames. The degradation of QD and GQD happens due to Unruh effect. Furthermore,
QD exhibits more robustness than GQD when the multipartite systems are exposed
to environment.Comment: 15 pages, 4 figures, 4 table
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