5,027 research outputs found
Psychiatric characterization of children with genetic causes of hyperandrogenism
Objective: Very little is known about the mental health status in children with genetic causes of hyperandrogenism. This study sought to characterize psychiatric morbidity in this group. Design/methods: Children (8-18 years) with the diagnosis of classic congenital adrenal hyperplasia (CAH) or familial male precocious puberty (FMPP) underwent a semi-structured psychiatric interview, the Kiddie Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version. According to sex and the literature, incidence of identified psychopathology was compared between the two endocrinological groups. We evaluated 72 patients: 54 CAH (21 females) and 18 FMPP. Results: Twenty-four (44.4%) CAH patients and 10 (55.6%) FMPP patients met the criteria for at least one lifetime psychiatric diagnosis. Attention-deficit hyperactivity disorder (ADHD) was present in 18.2% of CAH males, 44.4% of FMPP males, and one case (4.8%) in CAH females. A high rate of anxiety disorders was also found in all the three groups (17-21%). Relative to females with CAH, the FMPP patients exhibited higher rates of ADHD. Age at diagnosis and the treatment modalities were not associated with psychopathology. Rates of psychiatric disorder, specifically ADHD and anxiety disorders, were higher than in the general population. Conclusion: Although anxiety disorders may occur at an increased rate in children with chronic illness, androgens may contribute to higher risk for psychopathology in pediatric patients with genetic cause of excess androgen. Early diagnosis and treatment of childhood hyperandrogenism is essential for optimal development. The results suggest that assessment for psychiatric disorders should be part of the routine evaluation of these patients
Holographic Foam, Dark Energy and Infinite Statistics
Quantum fluctuations of spacetime give rise to quantum foam, and black hole
physics dictates that the foam is of holographic type. Applied to cosmology,
the holographic model requires the existence of dark energy which, we argue, is
composed of an enormous number of inert ``particles'' of extremely long
wavelength. These "particles" necessarily obey infinite statistics in which all
representations of the particle permutation group can occur. For every boson or
fermion in the present observable universe there could be such
"particles". We also discuss the compatibility between the holographic
principle and infinite statistics.Comment: 12 pages, LaTeX; added references and footnotes; version to appear in
Physics Letters
Knowledge of Driving Vehicle Licensing Agency guidelines among NHS doctors:A multicentre observational study
Objectives: Over half of the UK population holds a driver's licence. The DVLA have produced guidelines to ensure drivers with medical conditions drive safely. Doctors should ensure that patients are given appropriate information and advice if they have a medical condition affecting their driving. We sought to evaluate doctors' knowledge of DVLA guidelines. Design: A 25-point questionnaire was designed from DVLA guidelines (âThe DVLA Questionnaireâ). Five questions were included for each of neurology, cardiology, drug and alcohol abuse, visual, and respiratory disorders. Setting: Ealing Hospital, Northwick Park Hospital, Watford General Hospital, Norfolk and Norwich University Hospital and Leeds Teaching Hospitals Trust. Participants: 140 UK doctors. Main outcome measures: Questionnaire scores assessing knowledge of DVLA guidelines in five specialty areas. Results: The median overall questionnaire score was 28%, interquartile range 20â36% and range 0â100% [Watford 28%, Leeds 30%, Norfolk and Norwich 36%, Ealing 30%, Northwick Park 28%]. There were no significant differences between the scores for each centre (pâ=â0.1332), Mean scores for specialty areas were: neurology 33.1%, standard deviation 22.1; cardiology 35.6%, standard deviation 26.9; drug and alcohol abuse 30.6%, standard deviation 23.8; visual disorders 33.9%, standard deviation 23.5 and respiratory disorders 20.3%, standard deviation 24.8; overall score 30.7%. There was no significant difference between the scores of the specialty areas (pâ=â0.4060). Conclusions: Knowledge of DVLA guidelines in our cohort was low. There is a need for increased awareness among hospital doctors through focused education on driving restrictions for common medical conditions. Improving physician knowledge in this area may help optimise patient safety
Testing the boundaries of closely related daisy taxa using metabolomic profiling
Advances in high-throughput, comprehensive small molecule analytical techniques have seen the development of the field of metabolomics. The coupling of mass spectrometry with high-resolution chromatography provides extensive chemical profiles from complex biological extracts. These profiles include thousands of compounds linked to gene expression, and can be used as taxonomic characters. Studies have shown metabolite profiles to be taxon specific in a range of organisms, but few have investigated taxonomically problematic plant taxa. This study used a phenetic analysis of metabolite profiles to test taxonomic boundaries in the Olearia phlogopappa (Asteraceae) complex as delimited by morphological data. Metabolite profiles were generated from both field- and shade house-grown material, using liquid chromatography-mass spectrometry (LC-MS). Aligned profiles of 51 samples from 12 taxa gave a final dataset of over 10,000 features. Multivariate analyses of field and shade house material gave congruent results, both confirming the distinctiveness of the morphologically defined species and subspecies in this complex. Metabolomics has great potential in alpha taxonomy, especially for testing the boundaries of closely related taxa where DNA sequence data has been uninformative
Performance of a 62Zn/62Cu microgenerator in kit-based synthesis and delivery of [62Cu]CuâETS for PET perfusion imaging
The performance of a commercially produced 62Zn/62Cu microgenerator system, and an associated kit-based radiopharmaceutical synthesis method, was evaluated for clinical site production of [62Cu]Cu-ETS (ethylglyoxal bis(thiosemicarbazonato)copper(II)), an investigational agent for PET perfusion imaging. Using 37 generators, containing 1.84 ± 0.23 GBq 62Zn at 9:00 AM on the day of clinical use, a total of 45 patient doses of [62Cu]Cu-ETS (672 ± 172 MBq) were delivered without difficulty. 62Cu elution yields were high (approximately 90%), accompanied by extremely low 62Zn breakthrough (<0.001%). Radiopharmaceutical preparation, from the start-of-elution to time-of-injection, consumed less than five minutes. The 62Zn/62Cu microgenerator was a dependable source of short-lived positron-emitting 62Cu, and the kit-based synthesis proved to be rapid, robust, and highly reliable for âon-demandâ delivery of [62Cu]Cu-ETS for PET perfusion imaging
Spacetime Emergence and General Covariance Transmutation
Spacetime emergence refers to the notion that classical spacetime "emerges"
as an approximate macroscopic entity from a non-spatio-temporal structure
present in a more complete theory of interacting fundamental constituents. In
this article, we propose a novel mechanism involving the "soldering" of
internal and external spaces for the emergence of spacetime and the twin
transmutation of general covariance. In the context of string theory, this
mechanism points to a critical four dimensional spacetime background.Comment: 11 pages, v2: version to appear in MPL
Development of LRFD Procedures for Bridge Piles in IowaâVolume IV: Design Guide and Track Examples
With the goal of producing engineered foundation designs with consistent levels of reliability as well as fulfilling the Federal Highway Administration (FHWA) mandate that all new bridges initiated after October 1, 2007 be designed according to the Load and Resistance Factor Design (LRFD) approach, the Iowa Highway Research Board (IHRB) sponsored three research projects on driven piles (TR-573, -583 and -584). The research outcomes are presented in three reports entitled Development of LRFD Design Procedures for Bridge Piles in Iowa, Volumes I, II, and III, and other research information is available on the project web site at http://srg.cce.iastate.edu/lrfd/.
Upon incorporating the regional LRFD recommendations from the completed research into the Iowa DOT Bridge Design Manual (2010) as it is being rewritten under the new title of LRFD Bridge Design Manual (December 2011), and adopting the American Association of State Highway and Transportation Officials (AASHTO) LRFD Bridge Design Specifications (2010), this Volume IV for driven piles in Iowa was developed.
Following the layout of a design guide, the application of the LRFD approach is demonstrated using various pile design examples in three different tracks, which depend on the construction control method used for establishing the pile driving criteria. Piles are designed using the Iowa Blue Book method. The pile driving criteria are established using the Wave Equation Analysis Program (WEAP) in Track 1, the modified Iowa Engineering News Record (ENR) formula in Track 2, and the combination of WEAP and the Pile Driving Analyzer (PDA) with a subsequent pile signal matching analysis using the CAse Pile Wave Analysis Program (CAPWAP) in Track 3.
The track examples cover various pile types, three different soil profiles (cohesive, non-cohesive, and mixed) and special design considerations (piles on rock, scouring, downdrag, and uplift)
A Note on Agegraphic Dark Energy
Recently a new model of dynamical dark energy, or time-varying , was
proposed by Cai [arXiv:0707.4049] by relating the energy density of quantum
fluctuations in a Minkowski space-time, namely ,
where and t is the cosmic time, to the present day dark
energy density. In this note, we show that the model can be adjusted to the
present values of dark energy density parameter () and
the equation of state () only if the numerical
coefficient takes a reasonably large value () or the present
value of the gravitational coupling of q-field to (dark) matter is also
nonzero, namely, where
is the present value of dark energy density fraction. We also
discuss some of the difficulties of this proposal as a viable dark energy model
with a constant ; especially, the bound imposed on the dark energy density
parameter during big bang nucleosynthesis (BBN) requires . To overcome this drawback, we outline a few modifications where such
constraints can be weakened or relaxed. Finally, by establishing a
correspondence between the agegraphic dark energy scenario and the standard
scalar-field model, we also point out some interesting features of an
agegraphic quintessence model.Comment: 18 pages, several eps figures; significant changes in Secs. 2 & 3,
Journal versio
Avalanche Noise in Al0.52In0.48P Diodes
Multiplication and avalanche excess noise measurements have been undertaken on a series of AlInP homojunction p-i-n and n-i-p diodes with i region widths ranging from 0.04 to 0.89 ÎŒm, using 442 and 460 nm wavelength light. Low dark currents of 1000 kV/cm. For a given multiplication factor, the excess noise decreased as the avalanche width decreased due to the dead-space effect. Using 460 nm wavelength light, measurements showed that a separate absorption multiplication avalanche photodiode with a nominal multiplication region width of 0.2 ÎŒm had an effective k (hole to electron ionization coefficient ratio) of ~0.3
Five new INTEGRAL unidentified hard X-Ray sources uncovered by Chandra
The IBIS imager on board INTEGRAL, with a sensitivity better than a mCrab in
deep observations and a point source location accuracy of the order of few
arcminutes, has localized so far 723 hard X-ray sources in the 17--100 keV
energy band, of which a fraction of about 1/3 are still unclassified. The aim
of this research is to provide sub-arcsecond localizations of the unidentified
sources, necessary to pinpoint the optical and/or infrared counterpart of those
objects whose nature is so far unknown. The cross-correlation between the new
IBIS sources published within the fourth INTEGRAL/IBIS Survey catalogue and the
CHANDRA/ACIS data archive resulted in a sample of 5 not yet identified objects.
We present here the results of CHANDRA X-ray Observatory observations of these
five hard X-ray sources discovered by the INTEGRAL satellite. We associated IGR
J10447-6027 with IR source 2MASSJ10445192-6025115, IGR J16377-6423 with the
cluster CIZA J1638.2-6420, IGR J14193-6048 with the pulsar with nebula PSR
J1420-6048 and IGR J12562+2554 with the Quasar SDSSJ125610.42+260103.5. We
suggest that the counterpart of IGR J12288+0052 may be an AGN/QSO type~2 at a
confidence level of 90%.Comment: ApJ accepte
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