2,050 research outputs found

    Anomalies of oxygen measurements performed with Aanderaa optodes

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    Four sets of measurements performed between 2005 and 2010 in the deep central Atlantic, and in deep Mediterranean Sea, and the Arctic Ocean revealed a strange performance of Aanderaa Optode 3830 sensors mounted on RCM11 current meters in low current regimes (current speeds > 10 cm s- 1) . All oxygen data sets collected during these deployments showed significant drops of oxygen (of the order of 50-100 ìmol/l) affecting the Optode data stability in low hydrodynamic conditions (fig.1). High correlations between all acquired parameters (i.e. temperature, turbidity, speed and direction of currents) allowed verifying that no unusual event perturbed the mooring areas during the periods of acquisition, although natural events responsible of so abrupt, short and intense oxygen variations can’t be easily found. Despite the well-known performance of the Aanderaa Optodes, these experiences suggested that the data acquired by optodes installed on RCM11s could not be always reliable, especially in low energy systems (typical for the deep ocean) and that current speeds should always be considered in order to verify the reliability of the data recorded. A series of test in controlled water condition was performed in order to better understand eventual sensor dependence on speed current variations and to evaluate sensor stability in quasi-stationary water

    Analysis of Hydrogen Cyanide Hyperfine Spectral Components towards Star Forming Cores

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    Although hydrogen cyanide has become quite a common molecular tracing species for a variety of astrophysical sources, it, however, exhibits dramatic non-LTE behaviour in its hyperfine line structure. Individual hyperfine components can be strongly boosted or suppressed. If these so-called hyperfine line anomalies are present in the HCN rotational spectra towards low or high mass cores, this will affect the interpretation of various physical properties such as the line opacity and excitation temperature in the case of low mass objects and infall velocities in the case of their higher mass counterparts. This is as a consequence of the direct effects that anomalies have on the underlying line shape, be it with the line structural width or through the inferred line strength. This work involves the first observational investigation of these anomalies in two HCN rotational transitions, J=1!0 and J=3!2, towards both low mass starless cores and high mass protostellar objects. The degree of anomaly in these two rotational transitions is considered by computing the ratios of neighboring hyperfine lines in individual spectra. Results indicate some degree of anomaly is present in all cores considered in our survey, the most likely cause being line overlap effects among hyperfine components in higher rotational transitions.Comment: 8th Serbian Conference on Spectral Line Shapes in Astrophysics, Divicibare; 8 pages, 5 figure

    ALMA observations of the massive molecular outflow G331.512-0.103

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    The object of this study is one of the most energetic and luminous molecular outflows known in the Galaxy, G331.512-0.103. Observations with ALMA Band 7 (350 GHz; 0.86 mm) reveal a very compact, extremely young bipolar outflow and a more symmetric outflowing shocked shell surrounding a very small region of ionized gas. The velocities of the bipolar outflow are about 70 km s^{-1} on either side of the systemic velocity. The expansion velocity of the shocked shell is ~24 km s^{-1}, implying a crossing time of about 2000 yrs. Along the symmetry axis of the outflow, there is a velocity feature, which could be a molecular "bullet" of high-velocity dense material. The source is one of the youngest examples of massive molecular outflow found associated with a high-mass star.Comment: 9 pages, 4 figures, 1 table, Accepted for publication in The Astrophysical Journal Letters, small typos correcte

    "Idiopathic" mental retardation and new chromosomal abnormalities

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    Mental retardation is a heterogeneous condition, affecting 1-3% of general population. In the last few years, several emerging clinical entities have been described, due to the advent of newest genetic techniques, such as array Comparative Genomic Hybridization. The detection of cryptic microdeletion/microduplication abnormalities has allowed genotype-phenotype correlations, delineating recognizable syndromic conditions that are herein reviewed. With the aim to provide to Paediatricians a combined clinical and genetic approach to the child with cognitive impairment, a practical diagnostic algorithm is also illustrated. The use of microarray platforms has further reduced the percentage of "idiopathic" forms of mental retardation, previously accounted for about half of total cases. We discussed the putative pathways at the basis of remaining "pure idiopathic" forms of mental retardation, highlighting possible environmental and epigenetic mechanisms as causes of altered cognition

    A Pilot Survey for the H2_2O Southern Galactic Plane Survey (HOPS)

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    We describe observations with the Mopra radiotelescope designed to assess the feasibility of the H2_2O maser southern Galactic plane survey (HOPS). We mapped two one-square-degree regions along the Galactic plane using the new 12 mm receiver and the UNSW Mopra spectrometer (MOPS). We covered the entire spectrum between 19.5 and 27.5 GHz using this setup with the main aims of finding out which spectral lines can be detected with a quick mapping survey. We report on detected emission from H2_2O masers, NH3_3 inversion transitions (1,1), (2,2) and (3,3), HC3_3N (3-2), as well as several radio recombination lines.Comment: accepted by PAS

    The effects of estradiol levels on crossmodal perception: a study on the sound induced flash illusion in healthy and menstrually related migraine individuals

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    ObjectiveThe sound-induced flash illusion (SIFI) is a valid paradigm to study multisensorial perception. In the "fission" SIFI, multiple flashes are perceived when observing a single flash paired with two or more beeps. SIFI is largely dependent on visual and acoustic cortex excitability; in migraine, dysfunctional cortical excitability affects SIFI perception. Since estrogen peak occurring during ovulation can increase neuronal excitability, the present study aims to verify whether cortical excitability shifts linked to the menstrual cycle could influence SIFI.MethodsIn a comparative prospective study, we tested the effect of estrogens on crossmodal perception using the SIFI. We recruited 27 females in reproductive age, including 16 healthy and 11 menstrually related migraine females, testing their proneness to SIFI on day 14 (high estradiol) and day 27 (low estradiol) of menstrual cycle.ResultsWomen on day 14 reported less flashes than on day 27 (p = 0.02) in the fission illusion, suggesting a pro-excitatory effect of estradiol on visual cortex excitability during ovulation. Moreover, we confirmed that migraine women perceived less flashes (p = 0.001) than controls, independently from cycle phase. Non-migraineurs women significantly reported more flashes on day 27 than on day 14 (p = 0.04).ConclusionsThis study suggests that estradiol may influence the multisensory perception due to changes of visual cortex excitability, with high estradiol peak leading to increased visual cortical sensitivity during ovulation in non-migraineurs. Visual cortex hyperresponsiveness, here reflected by reduced SIFI, is not influenced by estradiol fluctuations in migraine women, as shown by reduced fission effects on day 14 and 27

    Effects of a cognitive behavioral self-help program and a computerized structured writing intervention on depressed mood for HIV-infected people:A pilot randomized controlled trial

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    Objective: The aim of the present study was to examine whether low-resource, cost-effective intervention programs can be effective in improving depressed mood in people with HIV. The efficacy of a cognitive-behavioral self-help program (CBS) and a computerized structured writing intervention (SWI) were tested in a pilot randomized controlled trial. Methods: Participants were members of a patient organization. They completed a pretest and posttest. The questionnaire included the HADS. Participants were randomly allocated to CBS (n=24), SWI (n=25) or a waiting list condition (WLC, n=24). To evaluate changes in the continuous outcome measure, a 3 × 2 (group × time) repeated measures ANCOVA was performed. Also, an ANCOVA was performed using change scores. Results: Respondents who followed the CBS improved significantly compared to the WLC. However, for people in the SWI condition no significant improvement on depression was found. Conclusion: This pilot study suggests that a low-resource, cost-effective CBS program seems to be effective in reducing depressed mood in people living with HIV. Practice implications: Because self-help programs can be delivered through regular mail or the internet, a high number of people could be reached while overcoming geographical and social barriers to treatment. © 2009 Elsevier Ireland Ltd

    Influence of Feeding Linseed on SCD Activity in Grazing Goat Mammary Glands

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    The effects of linseed feeding on the stearoyl-CoA desaturase (SCD) activity were evaluated on grazing dairy goats divided into two homogeneous groups (C, control, and L, treated) fed the same amount of concentrate which, for group L was supplemented with linseed. Milk yield was unaffected by the treatment. Group L showed significantly higher milk fat (4.10% vs 2.94%, p < 0.01) than group S. Within milk fatty acids, group C showed significantly higher levels of saturated fatty acids and lower values of mono-unsaturated and polyunsaturated fatty acids. In group L, total CLAs were higher than in group S (0.646% vs 0.311%; p < 0.01) mainly because of the differences in CLA cis9 trans 11 (0.623% vs 0.304%; p < 0.01). In treated animals, SCD activity, measured as cis9 C14:1/C14:0, was lower than in the control group, mainly in July and August
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