159 research outputs found
The Five Factor Model of personality and evaluation of drug consumption risk
The problem of evaluating an individual's risk of drug consumption and misuse
is highly important. An online survey methodology was employed to collect data
including Big Five personality traits (NEO-FFI-R), impulsivity (BIS-11),
sensation seeking (ImpSS), and demographic information. The data set contained
information on the consumption of 18 central nervous system psychoactive drugs.
Correlation analysis demonstrated the existence of groups of drugs with
strongly correlated consumption patterns. Three correlation pleiades were
identified, named by the central drug in the pleiade: ecstasy, heroin, and
benzodiazepines pleiades. An exhaustive search was performed to select the most
effective subset of input features and data mining methods to classify users
and non-users for each drug and pleiad. A number of classification methods were
employed (decision tree, random forest, -nearest neighbors, linear
discriminant analysis, Gaussian mixture, probability density function
estimation, logistic regression and na{\"i}ve Bayes) and the most effective
classifier was selected for each drug. The quality of classification was
surprisingly high with sensitivity and specificity (evaluated by leave-one-out
cross-validation) being greater than 70\% for almost all classification tasks.
The best results with sensitivity and specificity being greater than 75\% were
achieved for cannabis, crack, ecstasy, legal highs, LSD, and volatile substance
abuse (VSA).Comment: Significantly extended report with 67 pages, 27 tables, 21 figure
A systematic review and activation likelihood estimation meta-Analysis of the central innervation of the lower urinary tract: Pelvic floor motor control and micturition
Purpose Functional neuroimaging is a powerful and versatile tool to investigate central lower urinary tract (LUT) control. Despite the increasing body of literature there is a lack of comprehensive overviews on LUT control. Thus, we aimed to execute a coordinate based meta-Analysis of all PET and fMRI evidence on descending central LUT control, i.e. pelvic floor muscle contraction (PFMC) and micturition. Materials and methods A systematic literature search of all relevant libraries was performed in August 2020. Coordinates of activity were extracted from eligible studies to perform an activation likelihood estimation (ALE) using a threshold of uncorrected p 0.001. Results 20 of 6858 identified studies, published between 1997 and 2020, were included. Twelve studies investigated PFMC (1xPET, 11xfMRI) and eight micturition (3xPET, 5xfMRI). The PFMC ALE analysis (n = 181, 133 foci) showed clusters in the primary motor cortex, supplementary motor cortex, cingulate gyrus, frontal gyrus, thalamus, supramarginal gyrus, and cerebellum. The micturition ALE analysis (n = 107, 98 foci) showed active clusters in the dorsal pons, including the pontine micturition center, the periaqueductal gray, cingulate gyrus, frontal gyrus, insula and ventral pons. Overlap of PFMC and micturition was found in the cingulate gyrus and thalamus. Conclusions For the first time the involved core brain areas of LUT motor control were determined using ALE. Furthermore, the involved brain areas for PFMC and micturition are partially distinct. Further neuroimaging studies are required to extend this ALE analysis and determine the differences between a healthy and a dysfunctional LUT. This requires standardization of protocols and task-execution
Revisit of the Interaction between Holographic Dark Energy and Dark Matter
In this paper we investigate the possible direct, non-gravitational
interaction between holographic dark energy (HDE) and dark matter. Firstly, we
start with two simple models with the interaction terms
and , and then we move on to the general form . The cosmological constraints of the models are
obtained from the joint analysis of the present Union2.1+BAO+CMB+ data. We
find that the data slightly favor an energy flow from dark matter to dark
energy, although the original HDE model still lies in the 95.4% confidence
level (CL) region. For all models we find at the 95.4% CL. We show that
compared with the cosmic expansion, the effect of interaction on the evolution
of and is smaller, and the relative increment
(decrement) amount of the energy in the dark matter component is constrained to
be less than 9% (15%) at the 95.4% CL. By introducing the interaction, we find
that even when the big rip still can be avoided due to the existence of a
de Sitter solution at . We show that this solution can not be
accomplished in the two simple models, while for the general model such a
solution can be achieved with a large , and the big rip may be avoided
at the 95.4% CL.Comment: 26 pages, 9 figures, version accepted for publication in JCA
AdS Bubbles, Entropy and Closed String Tachyons
We study the conjectured connection between AdS bubbles (AdS solitons) and
closed string tachyon condensations. We confirm that the entanglement entropy,
which measures the degree of freedom, decreases under the tachyon condensation.
The entropies in supergravity and free Yang-Mills agree with each other
remarkably. Next we consider the tachyon condensation on the AdS twisted circle
and argue that its endpoint is given by the twisted AdS bubble, defined by the
double Wick rotation of rotating black 3-brane solutions. We calculated the
Casimir energy and entropy and checked the agreements between the gauge and
gravity results. Finally we show an infinite boost of a null linear dilaton
theory with a tachyon wall (or bubble), leads to a solvable time-dependent
background with a bulk tachyon condensation. This is the simplest example of
spacetimes with null boundaries in string theory.Comment: 45 pages, 6 figures, harvmac, eq.(2.16) corrected, references adde
Probing interaction and spatial curvature in the holographic dark energy model
In this paper we place observational constraints on the interaction and
spatial curvature in the holographic dark energy model. We consider three kinds
of phenomenological interactions between holographic dark energy and matter,
i.e., the interaction term is proportional to the energy densities of dark
energy (), matter (), and matter plus dark energy
(). For probing the interaction and spatial curvature in
the holographic dark energy model, we use the latest observational data
including the type Ia supernovae (SNIa) Constitution data, the shift parameter
of the cosmic microwave background (CMB) given by the five-year Wilkinson
Microwave Anisotropy Probe (WMAP5) observations, and the baryon acoustic
oscillation (BAO) measurement from the Sloan Digital Sky Survey (SDSS). Our
results show that the interaction and spatial curvature in the holographic dark
energy model are both rather small. Besides, it is interesting to find that
there exists significant degeneracy between the phenomenological interaction
and the spatial curvature in the holographic dark energy model.Comment: 11 pages, 5 figures; to appear in JCA
The effect of inhomogeneities on the distance to the last scattering surface and the accuracy of the CMB analysis
The standard analysis of the CMB data assumes that the distance to the last
scattering surface can be calculated using the distance-redshift relation as in
the Friedmann model. However, in the inhomogeneous universe, even if
=0, the distance relation is not the same as in the unperturbed
universe. This can be of serious consequences as a change of distance affects
the mapping of CMB temperature fluctuations into the angular power spectrum. In
addition, if the change of distance is relatively uniform no new temperature
fluctuations are generated. It is therefore a different effect than the lensing
or ISW effects which introduce additional CMB anisotropies. This paper shows
that the accuracy of the CMB analysis can be impaired by the accuracy of
calculation of the distance within the cosmological models. Since this effect
has not been fully explored before, to test how the inhomogeneities affect the
distance-redshift relation, several methods are examined: the Dyer-Roeder
relation, lensing approximation, and non-linear Swiss-Cheese model. In all
cases, the distance to the last scattering surface is different than when
homogeneity is assumed. The difference can be as low as 1% and as high as 80%.
Excluding extreme cases, the distance changes by about 20-30%. Since the
distance to the last scattering surface is set by the position of the CMB
peaks, in order to have a good fit, the distance needs to be adjusted. After
correcting the distance, the cosmological parameters change. Therefore, a not
properly estimated distance to the last scattering surface can be a major
source of systematics. This paper shows that if inhomogeneities are taken into
account when calculating the distance then models with positive spatial
curvature and with \Omega_\Lambda ~ 0.8-0.9 are preferred. The \Lambda CDM
model in most cases, is at odds with the current data.Comment: 18 pages, 6 figure
Relations between Financing and Output in the Not-for-Profit Hospital
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68639/2/10.1177_107755878804500204.pd
Gluttony, excess, and the fall of the planter class in the British Caribbean
Food and rituals around eating are a fundamental part of human existence. They can also be heavily politicized and socially significant. In the British Caribbean, white slaveholders were renowned for their hospitality towards one another and towards white visitors. This was no simple quirk of local character. Hospitality and sociability played a crucial role in binding the white minority together. This solidarity helped a small number of whites to dominate and control the enslaved majority. By the end of the eighteenth century, British metropolitan observers had an entrenched opinion of Caribbean whites as gluttons. Travelers reported on the sumptuous meals and excessive drinking of the planter class. Abolitionists associated these features of local society with the corrupting influences of slavery. Excessive consumption and lack of self-control were seen as symptoms of white creole failure. This article explores how local cuisine and white creole eating rituals developed as part of slave societies and examines the ways in which ideas about hospitality and gluttony fed into the debates over slavery that led to the dismantling of slavery and the fall of the planter class
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