843 research outputs found

    Napoleon Cybulski (1854–1919)

    Get PDF

    Molecular Gas Content of HI Monsters and Implications to Cold Gas Content Evolution in Galaxies

    Full text link
    We present 12CO (J=1-0) observations of a sample of local galaxies (0.04<z<0.08) with a large neutral hydrogen reservoir, or "HI monsters". The data were obtained using the Redshift Search Receiver on the FCRAO 14 m telescope. The sample consists of 20 HI-massive galaxies with M(HI)>3e10Msun from the ALFALFA survey and 8 LSBs with a comparable M(HI) (>1.5e10Msun). Our sample selection is purely based on the amount of neutral hydrogen, thereby providing a chance to study how atomic and molecular gas relate to each other in these HI-massive systems. We have detected CO in 15 out of 20 ALFALFA selected galaxies and 4 out of 8 LSBs with molecular gas mass M(H2) of (1-11)e9Msun. Their total cold gas masses of (2-7e10Msun make them some of the most gas-massive galaxies identified to date in the Local Universe. Observed trends associated with HI, H2, and stellar properties of the HI massive galaxies and the field comparison sample are analyzed in the context of theoretical models of galaxy cold gas content and evolution, and the importance of total gas content and improved recipes for handling spatially differentiated behaviors of disk and halo gas are identified as potential areas of improvement for the modeling.Comment: 18 pages, 11 figures, 2 tables; Accepted for publication in MNRA

    Effects of global O-GlcNAcylation on galectin gene-expression profiles in human cancer cell lines

    Get PDF
    Background/Aim: The effects of O-linked ÎČ-N-acetyl-D-glucosamine (O-GlcNAc) transferase (OGT) and O-GlcNAcase (OGA) inhibitors on galectin gene expression profiles were examined in MCF7, HT-29, and HL-60 cancer cell lines. Materials and Methods: Cell cultures were treated for 24 h with OGA inhibitor thiamet G or OGT inhibitor 2-acetamido-1,3,4,6-tetra-O-acetyl-2-deoxy-5-thio-α-D-glucopyranose, and global O-GlcNAc levels and expression of galectin genes were determined using an immunodot blot assay and real-time quantitative polymerase chain reaction. Results: Two galectin genes, LGALS3 in MCF7 cells and LGALS12 in HL-60 cells, were up-regulated by O-GlcNAc, whereas other cell-specific galectins were unresponsive to changes in O-GlcNAc level. Of interest, basal levels of O-GlcNAc in resting HL-60 and HT-29 cells were significantly higher than those in cells differentiated into neutrophilic or enterocytic lineages, respectively. Conclusion: O-GlcNAc-mediated signaling pathways may be involved in regulating the expression of only a limited number of galectin genes. Additional O-GlcNAc-dependent mechanisms may work at the protein level (galectin secretion and intracellular localization) and warrant further investigation

    Molecular vibration in cold collision theory

    Full text link
    Cold collisions of ground state oxygen molecules with Helium have been investigated in a wide range of cold collision energies (from 1 Ό\muK up to 10 K) treating the oxygen molecule first as a rigid rotor and then introducing the vibrational degree of freedom. The comparison between the two models shows that at low energies the rigid rotor approximation is very accurate and able to describe all the dynamical features of the system. The comparison between the two models has also been extended to cases where the interaction potential He - O2_2 is made artificially stronger. In this case vibration can perturb rate constants, but fine-tuning the rigid rotor potential can alleviate the discrepancies between the two models.Comment: 11 pages, 3 figure

    Risk factors for nonfatal self‐harm and suicide among adolescents: two nested case–control studies conducted in the UK Clinical Practice Research Datalink

    Get PDF
    Background The characteristics of adolescents who die by suicide have hitherto been examined in uncontrolled study designs, thereby precluding examination of risk factors. The degree to which antecedents of nonfatal self-harm and suicide at young age differ remains unknown. Method We delineated two nested case–control studies of patients aged 10–19 years using the Clinical Practice Research Datalink with interlinked hospital and national mortality records. Cases were adolescents who between 1st January 2003 and 31st December 2018 had died from suicide (N = 324) – study 1; experienced their first self-harm episode (N = 56,008) – study 2. In both studies, cases were matched on sex, age and practice-level deprivation quintile to 25 controls. By fitting conditional logistic regression, we examined how risks varied according to psychiatric diagnoses, prescribed psychotropic medication, patterns of clinical contact and area-level deprivation. Results Suicides occurred more often among boys (66%), but self-harm was more common in girls (68%). Most individuals who self-harmed or died from suicide presented to their GP at least once in the preceding year (85% and 75% respectively). Only a third of cases had one of the examined diagnostic categories recorded. Depression was most strongly associated with elevated risks for both outcomes (self-harm: OR 7.9; 95% CI 7.8–8.2; suicide: OR 7.4; 95% CI 5.5–9.9). Except for autism spectrum disorder, all other diagnostic categories were linked with similar risk elevations for self-harm as for suicide. Whilst self-harm risk rose incrementally with increasing levels of area-level deprivation, suicide risks did not. Conclusions We observed few marked differences in risk factor profiles for nonfatal self-harm versus suicide. As most adolescents who had harmed themselves or died by suicide were known to services in the preceding year, their underlying pathology may not be adequately identified and treated. Our findings highlight the need for a multiagency approach to treatment and prevention

    Temporal trends in annual incidence rates for psychiatric disorders and self-harm among children and adolescents in the UK, 2003-2018.

    Get PDF
    BACKGROUND: There has been growing concern in the UK over recent years that a perceived mental health crisis is affecting children and adolescents, although published epidemiological evidence is limited. METHODS: Two population-based UK primary care cohorts were delineated in the Aurum and GOLD datasets of the Clinical Practice Research Datalink (CPRD). We included data from 9,133,246 individuals aged 1-20 who contributed 117,682,651 person-years of observation time. Sex- and age-stratified annual incidence rates were estimated for attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) (age groups: 1-5, 6-9, 10-12, 13-16, 17-19), depression, anxiety disorders (6-9, 10-12, 13-16, 17-19), eating disorders and self-harm (10-12, 13-16, 17-19) during 2003-2018. We fitted negative binomial regressions to estimate incidence rate ratios (IRRs) to examine change in incidence between the first (2003) and final year (2018) year of observation and to examine sex-specific incidence. RESULTS: The results indicated that the overall incidence has increased substantially in both boys and girls in between 2003 and 2018 for anxiety disorders (IRR 3.51 95% CI 3.18-3.89), depression (2.37; 2.03-2.77), ASD (2.36; 1.72-3.26), ADHD (2.3; 1.73-3.25), and self-harm (2.25; 1.82-2.79). The incidence for eating disorders also increased (IRR 1.3 95% CI 1.06-1.61), but less sharply. The incidence of anxiety disorders, depression, self-harm and eating disorders was in absolute terms higher in girls, whereas the opposite was true for the incidence of ADHD and ASD, which were higher among boys. The largest relative increases in incidence were observed for neurodevelopmental disorders, particularly among girls diagnosed with ADHD or ASD. However, in absolute terms, the incidence was much higher for depression and anxiety disorders. CONCLUSION: The number of young people seeking help for psychological distress appears to have increased in recent years. Changes to diagnostic criteria, reduced stigma, and increased awareness may partly explain our results, but we cannot rule out true increases in incidence occurring in the population. Whatever the explanation, the marked rise in demand for healthcare services means that it may be more challenging for affected young people to promptly access the care and support that they need
    • 

    corecore