4,244 research outputs found
Remote sensing of Earth's atmosphere and surface using a digital array scanned interferometer: A new type of imaging spectrometer
The capabilities of the digital array scanned interferometer (DASI) class of instruments for measuring terrestrial radiation fields over the visible to mid-infrared are evaluated. DASI's are capable of high throughput, sensitivity and spectral resolution and have the potential for field-of-view spatial discrimination (an imaging spectrometer). The simplicity of design and operation of DASI's make them particularly suitable for field and airborne platform based remote sensing. The long term objective is to produce a versatile field instrument which may be applied toward a variety of atmospheric and surface studies. The operation of DASI and its advantages over other spectrometers are discussed
Institutional Responses to Self-Injurious Behavior among Inmates
To date, little research has systematically investigated perceptions of mental health professionals regarding perceived motivations for self-injury among prison inmates. To help fill this gap, descriptive techniques were used to examine self-injurious behavior among inmates from the perspective of correctional mental health professionals. A quantitative survey was used to assess perceptions of mental health staff regarding etiology, motivations, and manifestations of self-injury. A qualitative interview component was used to explicate responses from the survey. Findings indicate that inmate cutting, scratching, opening old wounds, and inserting objects were the most commonly witnessed behaviors. There were indications that self-injury occurred regularly and that a subset of inmates are responsible for recurrent events. Mental health professionals perceived the motivation for inmate self-injury to be both manipulative and a coping mechanism. Professionals described current management strategies and corresponding needs for training and resources
Electron and ion stagnation at the collision front between two laser produced plasmas
We report results from a combined optical interferometric and spectrally resolved imaging study on colliding laser produced aluminium plasmas. A Nomarski interferometer was used to probe the spatio-temporal distribution of electron densities at the collision front. Analysis of the resulting interferograms reveals the formation and evolution of a localized electron density feature with a well-defined profile reminiscent of a stagnation layer. Electron stagnation begins at a time delay of 10 ns after the peak of the plasma generating laser pulse. The peak electron density was found to exceed 10^19 cm^−3 and the layer remained well defined up to a time delay of ca 100 ns. Temporally and spectrally resolved optical imaging was also undertaken, to compare the Al^+ ion distribution with that of the 2D electron density profile. This revealed nascent stagnation of singly charged ions at a delay time of 20 ns. We attribute these results to the effects of space charge separation in the seed plasma plumes
Superconductivity induced by spark erosion in ZrZn2
We show that the superconductivity observed recently in the weak itinerant
ferromagnet ZrZn2 [C. Pfleiderer et al., Nature (London) 412, 58 (2001)] is due
to remnants of a superconducting layer induced by spark erosion. Results of
resistivity, susceptibility, specific heat and surface analysis measurements on
high-quality ZrZn2 crystals show that cutting by spark erosion leaves a
superconducting surface layer. The resistive superconducting transition is
destroyed by chemically etching a layer of 5 microns from the sample. No
signature of superconductivity is observed in rho(T) of etched samples at the
lowest current density measured, J=675 Am-2, and at T < 45 mK. EDX analysis
shows that spark-eroded surfaces are strongly Zn depleted. The simplest
explanation of our results is that the superconductivity results from an alloy
with higher Zr content than ZrZn2.Comment: Final published versio
Direct laryngoscopy and cervical spine stabilisation
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72396/1/j.1365-2044.1994.tb03327.x.pd
Fibroblasts derived from oesophageal adenocarcinoma differ in DNA methylation profile from normal oesophageal fibroblasts
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.Oesophageal adenocarcinoma (OAC) is increasing in incidence and has a poor prognosis. Tumour derived fibroblasts (TDFs) differ functionally from normal fibroblasts (NDFs), and play a pivotal role in cancer. Many of the differences persist through subculture. We measured the DNA methylation profiles of 10 TDFs from OAC with 12 NDF from normal oesophageal mucosa using Infinium HumanMethylation450 Beadchips and found they differed in multidimensional scaling analysis. We identified 4,856 differentially methylated CpGs (DMCs, adjusted p 0.15), of which 3,243 (66.8%) were hypomethylated in TDFs compared to NDFs. Hypermethylated DMCs were enriched at transcription start sites (TSSs) and in CpG islands, and depleted in transcriptional enhancers. Gene ontology analysis of genes with DMCs at TSSs revealed an enrichment of genes involved in development, morphogenesis, migration, adhesion, regulation of processes and response to stimuli. Alpha-smooth muscle actin (α-SMA) is a marker of activated fibroblasts and a poor prognostic indicator in OAC. Hypomethylated DMCs were observed at the TSS of transcript variant 2 of α-SMA, which correlated with an increase in α-SMA protein expression. These data suggest that DNA methylation may contribute to the maintenance of the TDF phenotype
The serotonin transporter promoter polymorphism moderates the continuity of behavioral inhibition in early childhood.
Persistently elevated behavioral inhibition (BI) in children is a marker of vulnerability to psychopathology. However, little research has considered the joint influences of caregiver and child factors that may moderate the continuity of BI in early childhood, particularly genetic variants that may serve as markers of biological plasticity, such as the serotonin transporter linked polymorphic region (5-HTTLPR). We explored this issue in 371 preschoolers and their caregivers, examining whether parent characteristics (i.e., overinvolvement or anxiety disorder) and child 5-HTTLPR influenced the continuity of BI between ages 3 and 5. Measures were observational ratings of child BI, observational and questionnaire measures of parenting, and parent interviews for anxiety disorder history, and children were genotyped for the 5-HTTLPR. Parent factors did not moderate the association between age 3 and age 5 BI; however, child BI at age 3 interacted with children\u27s 5-HTTLPR variants to predict age 5 BI, such that children with at least one copy of the short allele exhibited less continuity of BI over time relative to children without this putative plasticity variant. Findings are consistent with previous work indicating the 5-HTTLPR short variant increases plasticity to contextual influences, thereby serving to decrease the continuity of BI in early childhood
What the resonance peak cannot do
In certain cuprates, a spin 1 resonance mode is prominent in the magnetic
structure measured by neutron scattering. It has been proposed that this mode
is responsible for significant features seen in other spectroscopies, such as
photoemission and optical absorption, which are sensitive to the charge
dynamics, and even that this mode is the boson responsibile for ``mediating''
the superconducting pairing. We show that its small (measured) intensity and
weak coupling to electron-hole pairs (as deduced from the measured lifetime)
disqualifies the resonant mode from either proposed role.Comment: 4 pages, no figur
Single or Double Degenerate Progenitors? Searching for Shock Emission in the SDSS-II Type Ia Supernovae
From the set of nearly 500 spectroscopically confirmed type~Ia supernovae and
around 10,000 unconfirmed candidates from SDSS-II, we select a subset of 108
confirmed SNe Ia with well-observed early-time light curves to search for
signatures from shock interaction of the supernova with a companion star. No
evidence for shock emission is seen; however, the cadence and photometric noise
could hide a weak shock signal. We simulate shocked light curves using SN Ia
templates and a simple, Gaussian shock model to emulate the noise properties of
the SDSS-II sample and estimate the detectability of the shock interaction
signal as a function of shock amplitude, shock width, and shock fraction. We
find no direct evidence for shock interaction in the rest-frame -band, but
place an upper limit on the shock amplitude at 9% of supernova peak flux ( mag). If the single degenerate channel dominates type~Ia progenitors,
this result constrains the companion stars to be less than about 6
on the main sequence, and strongly disfavors red giant companions.Comment: 28 pages, 3 figure
Catechol-O-methyltransferase gene val158met polymorphism and depressive symptoms during early childhood
Catechol-O-Methyltransferase (COMT) is a critical regulator of catecholamine levels in the brain. A functional polymorphism of the COMT gene, val158met, has been linked to internalizing symptoms (i.e., depression and anxiety) in adolescents and adults. We extended this research by investigating whether the val158met polymorphism was associated with childhood symptoms of depression and anxiety in two independent samples of young children (Ns=476 and 409). In both samples, preschool-aged children were genotyped for the COMT val158met polymorphism. Symptoms of psychopathology were assessed via parent interviews and primary caregiver reports. In both samples, children homozygous for the val allele had higher levels of depressive symptoms compared to children with at least one copy of the met allele. Our findings extend previous research in older participants by showing links between the COMT val158met polymorphism and internalizing symptoms in early childhood. © 2013 Wiley Periodicals, Inc
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