3,316 research outputs found
Hinode EUV Imaging Spectrometer Observations of Solar Active Region Dynamics
The EUV Imaging Spectrometer (EIS) on the Hinode satellite is capable of
measuring emission line center positions for Gaussian line profiles to a
fraction of a spectral pixel, resulting in relative solar Doppler-shift
measurements with an accuracy of less than a km/s for strong lines. We show an
example of the application of that capability to an active region sit-and-stare
observation in which the EIS slit is placed at one location on the Sun and many
exposures are taken while the spacecraft tracking keeps the same solar location
within the slit. For the active region examined (NOAA 10930), we find that
significant intensity and Doppler-shift fluctuations as a function of time are
present at a number of locations. These fluctuations appear to be similar to
those observed in high-temperature emission lines with other space-borne
spectroscopic instruments. With its increased sensitivity over earlier
spectrometers and its ability to image many emission lines simultaneously, EIS
should provide significant new constraints on Doppler-shift oscillations in the
corona.Comment: 7 Pages, 7 figure
Non-symmetric liquid crystal dimer containing a carbohydrate-based moiety
Peer reviewedPublisher PD
Comprehensive Determination of the Hinode/EIS Roll Angle
We present a new coalignment method for the EUV Imaging Spectrometer (EIS) on
board the Hinode spacecraft. In addition to the pointing offset and spacecraft
jitter, this method determines the roll angle of the instrument, which has
never been systematically measured, and is therefore usually not corrected. The
optimal pointing for EIS is computed by maximizing the cross-correlations of
the Fe XII 195.119 \r{A} line with images from the 193 \r{A} band of the
Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory
(SDO). By coaligning 3336 rasters with high signal-to-noise ratio, we estimate
the rotation angle between EIS and AIA and explore the distribution of its
values. We report an average value of (-0.387 0.007)\deg. We also provide
a software implementation of this method that can be used to coalign any EIS
raster.Comment: Accepted for publication in Solar Physics, 11 pages, 7 figure
The Human Occupation Along the Steel Creek Floodplain: Results of an Intensive Archeological Survey for the L Area Reactivation Project, Savannah River Plant, Barnwell County, South Carolina
https://scholarcommons.sc.edu/archanth_books/1164/thumbnail.jp
Reduction of Injection-Related Risk Behaviors After Emergency Implementation of a Syringe Services Program During an HIV Outbreak
Objective: To describe injection-related HIV risk behaviors preimplementation and postimplementation of an emergency syringe services program (SSP) in Scott County, Indiana, after an HIV outbreak among persons who inject drugs (PWID).
Design: Mixed methods retrospective preâpost intervention analysis.
Methods: We analyzed routine SSP program data collected at first and most recent visit among clients with â„2 visits, â„7 days apart from April 4 to August 30, 2015, to quantify changes in injection-related risk behaviors. We also analyzed qualitative data collected from 56 PWID recruited in Scott County to understand factors contributing to these behaviors.
Results: SSP clients included in our analysis (n = 148, 62% of all SSP clients) reported significant (P < 0.001) reductions over a median 10 weeks (range 1â23) in syringe sharing to inject (18%â2%) and divide drugs (19%â4%), sharing other injection equipment (eg, cookers) (24%â5%), and number of uses of the same syringe [2 (interquartile range: 1â4) to 1 (interquartile range: 1â1)]. Qualitative study participants described access to sterile syringes and safer injection education through the SSP, as explanatory factors for these reductions. Injection frequency findings were mixed, but overall suggested no change. The number of syringes returned by SSP clients increased from 0 at first visit to median 57. All qualitative study participants reported using sharps containers provided by the SSP.
Conclusions: Analyses of an SSP program and in-depth qualitative interview data showed rapid reduction of injection-related HIV risk behaviors among PWID post-SSP implementation. Sterile syringe access as part of comprehensive HIV prevention is an important tool to control and prevent HIV outbreaks
Separate GABA Afferents to Dopamine Neurons Mediate Acute Action of Opioids, Development of Tolerance, and Expression of Withdrawal
SummaryGABA release from interneurons in VTA, projections from the nucleus accumbens (NAc), and rostromedial tegmental nucleus (RMTg) was selectively activated in rat brain slices. The inhibition induced by Ό-opioid agonists was pathway dependent. Morphine induced a 46% inhibition of IPSCs evoked from the RMTg, 18% from NAc, and IPSCs evoked from VTA interneurons were almost insensitive (11% inhibition). In vivo morphine treatment resulted in tolerance to the inhibition of RMTg, but not local interneurons or NAc, inputs. One common sign of opioid withdrawal is an increase in adenosine-dependent inhibition. IPSCs evoked from the NAc were potently inhibited by activation of presynaptic adenosine receptors, whereas IPSCs evoked from RMTg were not changed. Blockade of adenosine receptors selectively increased IPSCs evoked from the NAc during morphine withdrawal. Thus, the acute action of opioids, the development of tolerance, and the expression of withdrawal are mediated by separate GABA afferents to dopamine neurons
Procedures and methodology in the diagnostic evaluation of the manipulatory skills test
Procedures and methodology in the diagnostic evaluation of the manipulatory skills tes
Theta Phase-dependent Modulation of Perception by Concurrent Transcranial Alternating Current Stimulation and Periodic Visual Stimulation
Background: Sensory perception can be modulated by the phase of neural oscillations, especially in the theta and alpha ranges. Oscillatory activity in the visual cortex can be entrained by transcranial alternating current stimulation (tACS) as well as periodic visual stimulation (i.e., flicker). Combined tACS and visual flicker stimulation modulates blood- oxygen-level-dependent (BOLD) responses and concurrent 4 Hz auditory click-trains and tACS modulates auditory perception in a phase-dependent way. Objective: In the present study, we investigated if phase synchrony between concurrent tACS and periodic visual stimulation (i.e., flicker) can modulate performance on a visual matching task. Methods: Participants completed a visual matching task on a flickering visual stimulus while receiving either in-phase (0°) or asynchronous (180°, 90°, or 270°) tACS at alpha or theta frequency. Stimulation was applied over either occipital cortex or dorsolateral prefrontal cortex (DLPFC). Results: Visual performance was significantly better during theta frequency tACS over the visual cortex when it was in-phase (0°) with visual stimulus flicker, compared to anti-phase (180°). This effect did not appear with alpha frequency flicker or with DLPFC stimulation. Furthermore, a control sham group showed no effect. There were no significant performance differences amongst the asynchronous (180°, 90°, and 270°) phase conditions. Conclusion: Extending previous studies on visual and auditory perception, our results support a crucial role of oscillatory phase in sensory perception and demonstrate a behaviourally relevant combination of visual flicker and tACS. The spatial and frequency specificity of our results have implications for research on the functional organisation of perception
Alteration of Gene Expression Signatures of Cortical Differentiation and Wound Response in Lethal Clear Cell Renal Cell Carcinomas
Clear cell renal cell carcinoma (ccRCC) is the most common malignancy of the adult kidney and displays heterogeneity in clinical outcomes. Through comprehensive gene expression profiling, we have identified previously a set of transcripts that predict survival following nephrectomy independent of tumor stage, grade, and performance status. These transcripts, designated as the SPC (supervised principal components) gene set, show no apparent biological or genetic features that provide insight into renal carcinogenesis or tumor progression. We explored the relationship of this gene list to a set of genes expressed in different anatomical segments of the normal kidney including the cortex (cortex gene set) and the glomerulus (glomerulus gene set), and a gene set expressed after serum stimulation of quiescent fibroblasts (the core serum response or CSR gene set). Interestingly, the normal cortex, glomerulus (part of the normal renal cortex), and CSR gene sets captured more than 1/5 of the genes in the highly prognostic SPC gene set. Based on gene expression patterns alone, the SPC gene set could be used to sort samples from normal adult kidneys by the anatomical regions from which they were dissected. Tumors whose gene expression profiles most resembled the normal renal cortex or glomerulus showed better survival than those that did not, and those with expression features more similar to CSR showed poorer survival. While the cortex, glomerulus, and CSR signatures predicted survival independent of traditional clinical parameters, they were not independent of the SPC gene list. Our findings suggest that critical biological features of lethal ccRCC include loss of normal cortical differentiation and activation of programs associated with wound healing
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