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Electrical signature in polar night cloud base variations
Layer clouds are globally extensive. Their lower edges are charged negatively by the fair weather atmospheric electricity current flowing vertically through them. Using polar winter surface meteorological data from Sodankyla ̈ (Finland) and Halley (Antarctica), we find that when meteorological diurnal variations are weak, an appreciable diurnal cycle, on average, persists in the cloud base heights, detected using a laser ceilometer. The diurnal cloud base heights from both sites correlate more closely with the Carnegie curve of global atmospheric electricity than with local meteorological measurements. The cloud base sensitivities are indistinguishable between the northern and southern hemispheres, averaging a (4.0 ± 0.5) m rise for a 1% change in the fair weather electric current density. This suggests that the global fair weather current, which is affected by space weather, cosmic rays and the El Nin ̃o Southern Oscillation, is linked with layer cloud properties
Vitality, Language Use, and Life Satisfaction : A Study of Bilingual Hungarian Adolescents Living in Romania
This study examined the relationship between objective and subjective vitality, in-group language use, and life satisfaction among two groups of bilingual Hungarians adolescents living in Romania: a low objective vitality group from Cluj-Napoca/Kolozsvar, where Hungarians are the demographic minority, and a high objective vitality group from Sfantu Gheorghe/Sepsiszentgyorgy, where Hungarians are the demographic majority. Consistent with predictions, the high objective vitality group reported higher subjective Hungarian vitality, lower subjective Romanian vitality, more frequent use of the Hungarian language, and higher life satisfaction, compared with the low objective vitality group. The effects of objective vitality on language use were partially mediated by subjective Romanian (but not Hungarian) vitality. Conversely, the effects of objective vitality on life satisfaction were fully mediated by subjective Hungarian (but not Romanian) vitality.Peer reviewe
Systemic inflammatory response syndrome after major abdominal surgery predicted by early upregulation of TLR4 and TLR5
OBJECTIVES
To study innate immune pathways in patients undergoing hepatopancreaticobiliary surgery to understand mechanisms leading to enhanced inflammatory responses and identifying biomarkers of adverse clinical consequences.
BACKGROUND
Patients undergoing major abdominal surgery are at risk of life-threatening systemic inflammatory response syndrome (SIRS) and sepsis. Early identification of at-risk patients would allow tailored postoperative care and improve survival.
METHODS
Two separate cohorts of patients undergoing major hepatopancreaticobiliary surgery were studied (combined n = 69). Bloods were taken preoperatively, on day 1 and day 2 postoperatively. Peripheral blood mononuclear cells and serum were separated and immune phenotype and function assessed ex vivo.
RESULTS
Early innate immune dysfunction was evident in 12 patients who subsequently developed SIRS (postoperative day 6) compared with 27 who did not, when no clinical evidence of SIRS was apparent (preoperatively or days 1 and 2). Serum interleukin (IL)-6 concentration and monocyte Toll-like receptor (TLR)/NF-κB/IL-6 functional pathways were significantly upregulated and overactive in patients who developed SIRS (P < 0.0001). Interferon α-mediated STAT1 phosphorylation was higher preoperatively in patients who developed SIRS. Increased TLR4 and TLR5 gene expression in whole blood was demonstrated in a separate validation cohort of 30 patients undergoing similar surgery. Expression of TLR4/5 on monocytes, particularly intermediate CD14CD16 monocytes, on day 1 or 2 predicted SIRS with accuracy 0.89 to 1.0 (areas under receiver operator curves).
CONCLUSIONS
These data demonstrate the mechanism for IL-6 overproduction in patients who develop postoperative SIRS and identify markers that predict patients at risk of SIRS 5 days before the onset of clinical signs
A lesson on interrogations from detainees: Predicting self-reported confessions and cooperation
The ability to predict confessions and cooperation from the elements of an interrogation was examined. Incarcerated men (N = 100) completed a 50-item questionnaire about their most recent police interrogation, and regression analyses were performed on self-reported decisions to confess and cooperate. Results showed that the likelihood of an interrogation resulting in a confession was greatest when evidence strength and score on a humanitarian interviewing scale were high, and when the detainee had few previous convictions or did not seek legal advice. We also found that the level of cooperation was greatest when the humanitarian interviewing score was high, and when previous convictions were low. The implications of the findings for interrogation practices are discussed
Joubert syndrome: genotyping a Northern European patient cohort
Joubert syndrome (JBS) is a rare neurodevelopmental disorder belonging to the group of ciliary diseases. JBS is genetically heterogeneous, with >20 causative genes identified to date. A molecular diagnosis of JBS is essential for prediction of disease progression and genetic counseling. We developed a targeted next-generation sequencing (NGS) approach for parallel sequencing of 22 known JBS genes plus 599 additional ciliary genes. This method was used to genotype a cohort of 51 well-phenotyped Northern European JBS cases (in some of the cases, Sanger sequencing of individual JBS genes had been performed previously). Altogether, 21 of the 51 cases (41%) harbored biallelic pathogenic mutations in known JBS genes, including 14 mutations not previously described. Mutations in C5orf42 (12%), TMEM67 (10%), and AHI1 (8%) were the most prevalent. C5orf42 mutations result in a purely neurological Joubert phenotype, in one case associated with postaxial polydactyly. Our study represents a population-based cohort of JBS patients not enriched for consanguinity, providing insight into the relative importance of the different JBS genes in a Northern European population. Mutations in C5orf42 are relatively frequent (possibly due to a Dutch founder mutation) and mutations in CEP290 are underrepresented compared with international cohorts. Furthermore, we report a case with heterozygous mutations in CC2D2A and B9D1, a gene associated with the more severe Meckel–Gruber syndrome that was recently published as a potential new JBS gene, and discuss the significance of this finding
Localization of Events in Space-Time
The present paper deals with the quantum coordinates of an event in
space-time, individuated by a quantum object. It is known that these
observables cannot be described by self-adjoint operators or by the
corresponding spectral projection-valued measure. We describe them by means of
a positive-operator-valued (POV) measure in the Minkowski space-time,
satisfying a suitable covariance condition with respect to the Poincare' group.
This POV measure determines the probability that a measurement of the
coordinates of the event gives results belonging to a given set in space-time.
We show that this measure must vanish on the vacuum and the one-particle
states, which cannot define any event. We give a general expression for the
Poincare' covariant POV measures. We define the baricentric events, which lie
on the world-line of the centre-of-mass, and we find a simple expression for
the average values of their coordinates. Finally, we discuss the conditions
which permit the determination of the coordinates with an arbitrary accuracy.Comment: 31 pages, latex, no figure
Modelling the spatial distribution of DEM Error
Assessment of a DEM’s quality is usually undertaken by deriving a measure of DEM accuracy – how close the DEM’s elevation values are to the true elevation. Measures such as Root Mean Squared Error and standard deviation of the error are frequently used. These measures summarise elevation errors in a DEM as a single value. A more detailed description of DEM accuracy would allow better understanding of DEM quality and the consequent uncertainty associated with using DEMs in analytical applications. The research presented addresses the limitations of using a single root mean squared error (RMSE) value to represent the uncertainty associated with a DEM by developing a new technique for creating a spatially distributed model of DEM quality – an accuracy surface. The technique is based on the hypothesis that the distribution and scale of elevation error within a DEM are at least partly related to morphometric characteristics of the terrain. The technique involves generating a set of terrain parameters to characterise terrain morphometry and developing regression models to define the relationship between DEM error and morphometric character. The regression models form the basis for creating standard deviation surfaces to represent DEM accuracy. The hypothesis is shown to be true and reliable accuracy surfaces are successfully created. These accuracy surfaces provide more detailed information about DEM accuracy than a single global estimate of RMSE
Comparative performance of some popular ANN algorithms on benchmark and function approximation problems
We report an inter-comparison of some popular algorithms within the
artificial neural network domain (viz., Local search algorithms, global search
algorithms, higher order algorithms and the hybrid algorithms) by applying them
to the standard benchmarking problems like the IRIS data, XOR/N-Bit parity and
Two Spiral. Apart from giving a brief description of these algorithms, the
results obtained for the above benchmark problems are presented in the paper.
The results suggest that while Levenberg-Marquardt algorithm yields the lowest
RMS error for the N-bit Parity and the Two Spiral problems, Higher Order
Neurons algorithm gives the best results for the IRIS data problem. The best
results for the XOR problem are obtained with the Neuro Fuzzy algorithm. The
above algorithms were also applied for solving several regression problems such
as cos(x) and a few special functions like the Gamma function, the
complimentary Error function and the upper tail cumulative
-distribution function. The results of these regression problems
indicate that, among all the ANN algorithms used in the present study,
Levenberg-Marquardt algorithm yields the best results. Keeping in view the
highly non-linear behaviour and the wide dynamic range of these functions, it
is suggested that these functions can be also considered as standard benchmark
problems for function approximation using artificial neural networks.Comment: 18 pages 5 figures. Accepted in Pramana- Journal of Physic
Validation and Initial Characterization of the Long Period Planet Kepler-1654 b
Fewer than 20 transiting Kepler planets have periods longer than one year.
Our early search of the Kepler light curves revealed one such system,
Kepler-1654 b (originally KIC~8410697b), which shows exactly two transit events
and whose second transit occurred only 5 days before the failure of the second
of two reaction wheels brought the primary Kepler mission to an end. A number
of authors have also examined light curves from the Kepler mission searching
for long period planets and identified this candidate. Starting in Sept. 2014
we began an observational program of imaging, reconnaissance spectroscopy and
precision radial velocity measurements which confirm with a high degree of
confidence that Kepler-1654 b is a {\it bona fide} transiting planet orbiting a
mature G2V star (TK, [Fe/H]=-0.08) with a semi-major axis of 2.03
AU, a period of 1047.84 days and a radius of 0.820.02 R. Radial
Velocity (RV) measurements using Keck's HIRES spectrometer obtained over 2.5
years set a limit to the planet's mass of ) M. The bulk
density of the planet is similar to that of Saturn or possibly lower. We assess
the suitability of temperate gas giants like Kepler-1654b for transit
spectroscopy with the James Webb Space Telescope since their relatively cold
equilibrium temperatures (TK) make them interesting from the
standpoint of exo-planet atmospheric physics. Unfortunately, these low
temperatures also make the atmospheric scale heights small and thus
transmission spectroscopy challenging. Finally, the long time between transits
can make scheduling JWST observations difficult---as is the case with
Kepler-1654b.Comment: accepted to Astronomical Journa
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