981 research outputs found
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A survey of 557 GHz water vapor emission in the NGC 1333 molecular cloud
Using NASA\u27s Submillimeter Wave Astronomy Satellite (SWAS), we have examined the production of water in quiescent and shocked molecular gas through a survey of the 556.936 GHz 110-101 transition of ortho-H2O in the NGC 1333 molecular core. These observations reveal broad emission lines associated with the IRAS 2, IRAS 4, IRAS 7, and HH 7-11 outflows. Toward three positions we detect narrow (Îv ~ 2-3 km s-1) emission lines clearly associated with the ambient gas. The SWAS observations, with a resolution of ~4\u27, are supplemented with observations from the Infrared Space Observatory (ISO) and by an unbiased survey of a ~17\u27 Ă 15\u27 area, with ~50\u27\u27 resolution, in the low-J transitions of CO, 13CO, C18O, N2H+, CH3OH, and SiO. Using these combined data sets, with consistent assumptions, we find beam-averaged ortho-H2O abundances of greater than 10-6 relative to H2 for all four outflows. A comparison of SWAS and ISO water data is consistent with nondissociative shock models, provided the majority of the ortho-H2O (110-101) emission arises from cool postshock material with enhanced abundances. In the ambient gas the ortho-H2O abundance is found to lie between 0.1 Ă 10-7 and 1 Ă 10-7 relative to H2 and is enhanced when compared to cold prestellar molecular cores. A comparison of the water emission with tracers of dense condensations and shock chemistry finds no clear correlation. However, the water emission appears to be associated with the presence of luminous external heating sources that power the reflection nebula and the photodissociation region (PDR). Simple PDR models are capable of reproducing the water and high-J 13CO emission, suggesting that a PDR may account for the excitation of water in low-density undepleted gas, as suggested by Spaans & van Dishoeck
Ward's Hierarchical Clustering Method: Clustering Criterion and Agglomerative Algorithm
The Ward error sum of squares hierarchical clustering method has been very
widely used since its first description by Ward in a 1963 publication. It has
also been generalized in various ways. However there are different
interpretations in the literature and there are different implementations of
the Ward agglomerative algorithm in commonly used software systems, including
differing expressions of the agglomerative criterion. Our survey work and case
studies will be useful for all those involved in developing software for data
analysis using Ward's hierarchical clustering method.Comment: 20 pages, 21 citations, 4 figure
An international comparative study of blood pressure in populations of European vs. African descent
Background: The consistent finding of higher prevalence of hypertension in US blacks compared
to whites has led to speculation that African-origin populations are particularly susceptible to this
condition. Large surveys now provide new information on this issue.
Methods: Using a standardized analysis strategy we examined prevalence estimates for 8 white
and 3 black populations (N = 85,000 participants).
Results: The range in hypertension prevalence was from 27 to 55% for whites and 14 to 44% for
blacks.
Conclusions: These data demonstrate that not only is there a wide variation in hypertension
prevalence among both racial groups, the rates among blacks are not unusually high when viewed
internationally. These data suggest that the impact of environmental factors among both
populations may have been under-appreciated
Atomoxetine for the treatment of Attention-Deficit/Hyperactivity Disorder (ADHD) in children with ADHD and dyslexia
<p>Abstract</p> <p>Background</p> <p>The objective of this study was to assess the effects of atomoxetine on treating attention-deficit/hyperactivity disorder (ADHD), on reading performance, and on neurocognitive function in youth with ADHD and dyslexia (ADHD+D).</p> <p>Methods</p> <p>Patients with ADHD (n = 20) or ADHD+D (n = 36), aged 10-16 years, received open-label atomoxetine for 16 weeks. Data from the ADHD Rating Scale-IV (ADHDRS-IV), Kaufman Test of Educational Achievement (K-TEA), Working Memory Test Battery for Children (WMTB-C), and Life Participation Scale for ADHD-Child Version (LPS-C) were assessed.</p> <p>Results</p> <p>Atomoxetine demonstrated significant improvement for both groups on the ADHDRS-IV, LPS-C, and K-TEA reading comprehension standard and composite scores. K-TEA spelling subtest improvement was significant for the ADHD group, whereas the ADHD+D group showed significant reading decoding improvements. Substantial K-TEA reading and spelling subtest age equivalence gains (in months) were achieved for both groups. The WMTB-C central executive score change was significantly greater for the ADHD group. Conversely, the ADHD+D group showed significant phonological loop score enhancement by visit over the ADHD group. Atomoxetine was well tolerated, and commonly reported adverse events were similar to those previously reported.</p> <p>Conclusions</p> <p>Atomoxetine reduced ADHD symptoms and improved reading scores in both groups. Conversely, different patterns and magnitude of improvement in working memory component scores existed between ADHD and ADHD+D patients. Though limited by small sample size, group differences in relation to the comparable changes in improvement in ADHD symptoms could suggest that brain systems related to the therapeutic benefit of atomoxetine in reducing ADHD symptoms may be different in individuals with ADHD+D and ADHD without dyslexia.</p> <p>Trial Registration</p> <p>Clinical Trial Registry: ClinicalTrials.gov: NCT00191048</p
Acute atomoxetine treatment of younger and older children with ADHD: A meta-analysis of tolerability and efficacy
<p>Abstract</p> <p>Background</p> <p>Atomoxetine is FDA-approved as a treatment of attention-deficit/hyperactivity disorder (ADHD) in patients aged 6 years to adult. Among pediatric clinical trials of atomoxetine to date, six with a randomized, double-blind, placebo-controlled design were used in this meta-analysis. The purpose of this article is to describe and compare the treatment response and tolerability of atomoxetine between younger children (6â7 years) and older children (8â12 years) with ADHD, as reported in these six acute treatment trials.</p> <p>Methods</p> <p>Data from six clinical trials of 6â9 weeks duration were pooled, yielding 280 subjects, ages 6â7 years, and 860 subjects, ages 8â12 years with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV)-diagnosed ADHD. Efficacy was analyzed using the ADHD Rating Scale-IV (ADHD-RS), Conners' Parent Rating Scale-revised (CPRS-R:S), and the Clinical Global Impression of ADHD Severity (CGI-ADHD-S).</p> <p>Results</p> <p>Atomoxetine was superior to placebo in both age categories for mean (SD) change in ADHD-RS total, total T, and subscale scores; 3 CPRS-R:S subscales; and CGI-ADHD-S from baseline. Although there were no significant treatment differentials between the age groups for these efficacy measures, the age groups themselves, regardless of treatment, were significantly different for ADHD-RS total (younger: ATX = -14.2 [13.8], PBO = -4.6 [10.4]; older: ATX = -15.4 [13.2], PBO = -7.3 [12.0]; p = .001), total T (younger: ATX = -15.2 [14.8], PBO = -4.9 [11.2]; older: ATX = -16.4 [14.6], PBO = -7.9 [13.1]; p = .003), and subscale scores (Inattentive: younger: ATX = -7.2 [7.5], PBO = -2.4 [5.7]; older: ATX = -8.0 [7.4], PBO = -3.9 [6.7]; p = .043; Hyperactive/Impulsive: younger: ATX = -7.0 [7.2], PBO = -2.1 [5.4]; older: ATX = -7.3 [7.0], PBO = -3.4 [6.3]; p < .001), as well as the CGI-ADHD-S score (younger: ATX = -1.2 [1.3], PBO = -0.5 [0.9]; older: ATX = -1.4 [1.3], PBO = -0.7 [1.1]; p = .010). Although few subjects discontinued from either age group due to adverse events, a significant treatment-by-age-group interaction was observed for abdominal pain (younger: ATX = 19%, PBO = 6%; older: ATX = 15%, PBO = 13%; p = .044), vomiting (younger: ATX = 14%, PBO = 2%; older: ATX = 9%, PBO = 6%; p = .053), cough (younger: ATX = 10%, PBO = 6%; older: ATX = 3%, PBO = 9%; p = .007), and pyrexia (younger: ATX = 5%, PBO = 2%; older: ATX = 3%, PBO = 5%; p = .058).</p> <p>Conclusion</p> <p>Atomoxetine is an effective and generally well-tolerated treatment of ADHD in both younger and older children as assessed by three recognized measures of symptoms in six controlled clinical trials.</p> <p>Trial Registration</p> <p>Not Applicable.</p
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Extended [C I] and (CO)-C-13 (5 -\u3e 4) emission in M17SW
We mapped a 13 Ă 22 pc region in emission from 492 GHz [C I] and, for the first time, 551 GHz 13CO (5 â 4) in the giant molecular cloud M17SW. The morphologies of the [C I] and 13CO emission are strikingly similar. The extent and intensity of the [C I] and 13CO (5 â 4) emission is explained as arising from photodissociation regions on the surfaces of embedded molecular clumps. Modeling of the 13CO (5 â 4) emission in comparison to 13CO (1 â 0) indicates a temperature gradient across the cloud, peaking to at least 63 K near the M17 ionization front and decreasing to at least 20 K at the western edge of the cloud. We see no correlation between gas density and column density. The beam-averaged column density of C I in the core is 1 Ă 1018 cm-2, and the mean column density ratio N(C I)/N(CO) is about 0.4. The variations of N(C I)/N(CO) with position in M17SW indicate a similar clump size distribution throughout the cloud
Chronic diarrhea associated with persistent norovirus excretion in patients with chronic lymphocytic leukemia: report of two cases
BACKGROUND: Chronic diarrhea in patients treated with immunosuppressive agents or suffering from immunosuppressive disease can represent a diagnostic and therapeutic challenge to the clinician. Norovirus infection, a major cause of acute epidemic diarrhea, has been described as a cause of chronic diarrhea in patients who are immunosuppressed, including transplant recipients and the very young. CASE PRESENTATIONS: We describe two patients, a 64 year-old man and a 59 year-old woman, both suffering from chronic lymphocytic leukemia and hypogammaglobulinemia, who developed chronic diarrhea resistant to therapy. In both cases, after months of symptoms, persistent norovirus infection--documented by repeatedly-positive high-sensitivity stool enzyme immunoassay--was found to be the cause. Both patients died with active diarrheal symptoms. CONCLUSIONS: We describe the first cases of advanced chronic lymphocytic leukemia to suffer from chronic symptomatic norovirus infection. Clinicians caring for such patients, particularly those with concomitant hypogammaglobulinema, who have chronic unexplained diarrhea, should consider norovirus infection in the differential diagnosis
The role of multiple marks in epigenetic silencing and the emergence of a stable bivalent chromatin state
We introduce and analyze a minimal model of epigenetic silencing in budding
yeast, built upon known biomolecular interactions in the system. Doing so, we
identify the epigenetic marks essential for the bistability of epigenetic
states. The model explicitly incorporates two key chromatin marks, namely H4K16
acetylation and H3K79 methylation, and explores whether the presence of
multiple marks lead to a qualitatively different systems behavior. We find that
having both modifications is important for the robustness of epigenetic
silencing. Besides the silenced and transcriptionally active fate of chromatin,
our model leads to a novel state with bivalent (i.e., both active and
silencing) marks under certain perturbations (knock-out mutations, inhibition
or enhancement of enzymatic activity). The bivalent state appears under several
perturbations and is shown to result in patchy silencing. We also show that the
titration effect, owing to a limited supply of silencing proteins, can result
in counter-intuitive responses. The design principles of the silencing system
is systematically investigated and disparate experimental observations are
assessed within a single theoretical framework. Specifically, we discuss the
behavior of Sir protein recruitment, spreading and stability of silenced
regions in commonly-studied mutants (e.g., sas2, dot1) illuminating the
controversial role of Dot1 in the systems biology of yeast silencing.Comment: Supplementary Material, 14 page
The longitudinal relationship between emotion awareness and internalising symptoms during late childhood
Emotion awareness, the ability to reflect upon the own emotions, is assumed to contribute to better mental health. However, empirical support for this relationship has only been cross-sectional. In this study we examined the extent to which individual differences in changes in emotion awareness over time can explain individual differences in changes in symptoms of internalising problems (depression, fear, worrying and ruminative thoughts). Children and young teenagers (368 boys and 295 girls) were asked four times to fill out self-report questionnaires, with a 6-month time interval between each time. The mean age was 10Â years during the first data collection. Longitudinal multilevel analyses showed that the variance in emotion awareness trends was highly predictive for the variance in trends for internalizing problems over time. The ability to differentiate discrete emotions was a strong predictor and negatively contributed to all internalising symptoms. In addition, a diminished tendency to address and value emotions contributed to more depressive symptoms; whereas hiding the own emotions contributed to more worrying and ruminative thoughts. The outcomes show that individual differences in emotion awareness over time make a strong, and, above all, negative contribution to the prediction of the individual differences in various internalizing symptoms. The fact that several aspects of emotional (dys)functioning are uniquely related to different kinds of internalizing problems gives valuable and useful information not only theoretically but also clinically about the distinctive nature of these problems
Resveratrol-induced cytotoxicity in human Burkitt's lymphoma cells is coupled to the unfolded protein response
<p>Abstract</p> <p>Background</p> <p>Resveratrol (RES), a natural phytoalexin found at high levels in grapes and red wine, has been shown to induce anti-proliferation and apoptosis of human cancer cell lines. However, the underlying molecular mechanisms are at present only partially understood.</p> <p>Method</p> <p>The effects of RES on activation of unfolded protein responses (UPR) were evaluated using Western blotting, semi-quantitative and real-time RT-PCR. Cell death was evaluated using Annexin V/PI staining and subsequent FACS.</p> <p>Results</p> <p>Similar as tunicamycin, treatment with RES lead to the activation of all 3 branches of the UPR, with early splicing of XBP-1 indicative of IRE1 activation, phosphorylation of eIF2Îą consistent with ER resident kinase (PERK) activation, activating transcription factor 6 (ATF6) splicing, and increase in expression levels of the downstream molecules GRP78/BiP, GRP94 and CHOP/GADD153 in human Burkitt's lymphoma Raji and Daudi cell lines. RES was shown to induce cell death, which could be attenuated by thwarting upregulation of CHOP.</p> <p>Conclusions</p> <p>Our data suggest that activation of the apoptotic arm of the UPR and its downstream effector CHOP/GADD153 is involved, at least in part, in RES-induced apoptosis in Burkitt's lymphoma cells.</p
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