721 research outputs found

    Does alpha phase modulate visual target detection? Three experiments with tACS-phase-based stimulus presentation

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    In recent years, the influence of alpha (7–13 Hz) phase on visual processing has received a lot of attention. Magneto‐/encephalography (M/EEG) studies showed that alpha phase indexes visual excitability and task performance. Studies with transcranial alternating current stimulation (tACS) aim to modulate oscillations and causally impact task performance. Here, we applied right occipital tACS (O2 location) to assess the functional role of alpha phase in a series of experiments. We presented visual stimuli at different pre‐determined, experimentally controlled, phases of the entraining tACS signal, hypothesizing that this should result in an oscillatory pattern of visual performance in specifically left hemifield detection tasks. In experiment 1, we applied 10 Hz tACS and used separate psychophysical staircases for six equidistant tACS‐phase conditions, obtaining contrast thresholds for detection of visual gratings in left or right hemifield. In experiments 2 and 3, tACS was at EEG‐based individual peak alpha frequency. In experiment 2, we measured detection rates for gratings with (pseudo‐)fixed contrast. In experiment 3, participants detected brief luminance changes in a custom‐built LED device, at eight equidistant alpha phases. In none of the experiments did the primary outcome measure over phase conditions consistently reflect a one‐cycle sinusoid. However, post hoc analyses of reaction times (RT) suggested that tACS alpha phase did modulate RT for specifically left hemifield targets in both experiments 1 and 2 (not measured in experiment 3). This observation requires future confirmation, but is in line with the idea that alpha phase causally gates visual inputs through cortical excitability modulation

    Shape Isomerism at N = 40: Discovery of a Proton Intruder in 67Co

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    The nuclear structure of 67Co has been investigated through 67Fe beta-decay. The 67Fe isotopes were produced at the LISOL facility in proton-induced fission of 238U and selected using resonant laser ionization combined with mass separation. The application of a new correlation technique unambiguously revealed a 496(33) ms isomeric state in 67Co at an unexpected low energy of 492 keV. A 67Co level scheme has been deduced. Proposed spin and parities suggest a spherical (7/2-) 67Co ground state and a deformed first excited (1/2-) state at 492 keV, interpreted as a proton 1p-2h prolate intruder state.Comment: 4 pages, 5 figures, preprint submitted to Physical Review Letter

    Word reading in monolingual and bilingual children with developmental language disorder

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    Many children with developmental language disorder (DLD) are reported to have word reading difficulties. However, previous research has focused mostly on monolingual children. The present study used two existing datasets to assess word reading outcomes of bilingual children with DLD. In Study 1, we compared word reading outcomes of monolingual and bilingual children with and without DLD (n = 93 monolingual DLD; n = 33 bilingual DLD, n = 42 monolingual TD; n = 74 bilingual TD). In Study 2, we compared those of monolingual (n = 91) and bilingual children with DLD (n = 51) on the basis of school record data. Findings from both studies show mean poor word reading outcomes and a high incidence of poor readers in the groups of children with DLD. Despite lower oral language outcomes of bilingual children in the mainstream language, reading outcomes of monolingual and bilingual children (with/without DLD) did not differ or outcomes were even better for the bilingual children. Overall, these findings indicate that DLD is a risk factor for word reading difficulties, while bilingualism is not

    In-gas-cell laser ionization spectroscopy in the vicinity of 100Sn: Magnetic moments and mean-square charge radii of N=50-54 Ag

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    In-gas-cell laser ionization spectroscopy studies on the neutron deficient 97-101Ag isotopes have been performed with the LISOL setup. Magnetic dipole moments and mean-square charge radii have been determined for the first time with the exception of 101Ag, which was found in good agreement with previous experimental values. The reported results allow tentatively assigning the spin of 97,99Ag to 9/2 and confirming the presence of an isomeric state in these two isotopes, whose collapsed hyperfine structure suggests a spin of 1/2 . The effect of the N=50 shell closure is not only manifested in the magnetic moments but also in the evolution of the mean-square charge radii of the isotopes investigated, in accordance with the spherical droplet model predictions

    The links between prenatal stress and offspring development and psychopathology: disentangling environmental and inherited influences

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    Background. Exposure to prenatal stress is associated with later adverse health and adjustment outcomes. This is generally presumed to arise through early environmentally mediated programming effects on the foetus. However, associations could arise through factors that influence mothers’ characteristics and behaviour during pregnancy which are inherited by offspring. Method. A ‘ prenatal cross-fostering ’ design where pregnant mothers are related or unrelated to their child as a result of in vitro fertilization (IVF) was used to disentangle maternally inherited and environmental influences. If links between prenatal stress and offspring outcome are environmental, association should be observed in unrelated as well as related mother–child pairs. Offspring birth weight and gestational age as well as mental health were the outcomes assessed. Results. Associations between prenatal stress and offspring birth weight, gestational age and antisocial behaviour were seen in both related and unrelated mother–offspring pairs, consistent with there being environmental links. The association between prenatal stress and offspring anxiety in related and unrelated groups appeared to be due to current maternal anxiety/depression rather than prenatal stress. In contrast, the link between prenatal stress and offspring attention deficit hyperactivity disorder was only present in related mother–offspring pairs and therefore was attributable to inherited factors. Conclusions. Genetically informative designs can be helpful in testing whether inherited factors contribute to the association between environmental risk factors and health outcomes. These results suggest that associations between prenatal stress and offspring outcomes could arise from inherited factors and post-natal environmental factors in addition to causal prenatal risk effects

    Optical Scattering Measurements of Laser Induced Damage in the Intraocular Lens

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    This study optically determines whether the amount of light scatter due to laser-induced damage to the intraocular lens (IOL) is significant in relation to normal straylight values in the human eye. Two IOLs with laser-induced damage were extracted from two donor eyes. Each IOL had 15 pits and/or cracks. The surface area of each pit was measured using a microscope. For 6 pits per intraocular lens the point spread function (PSF) in terms of straylight was measured and the total straylight for all 15 pits was estimated. The damage in the IOLs was scored as mild/moderate. The total damaged surface areas, for a 3.5 mm pupil, in the two IOLs were 0.13% (0.0127 mm2) and 0.66% (0.064 mm2), respectively. The angular dependence of the straylight caused by the damage was similar to that of the normal PSF. The total average contribution to straylight was log(s) = −0.82 and −0.42, much less than the straylight value of the normal eye

    Novel high-throughput fluorescence-based assay for the identification of nematocidal compounds that target the blood-feeding pathway

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    Hookworm infections cause a neglected tropical disease (NTD) affecting ~740 million people worldwide, principally those living in disadvantaged communities. Infections can cause high morbidity due to their impact on nutrient uptake and their need to feed on host blood, resulting in a loss of iron and protein, which can lead to severe anaemia and impaired cognitive development in children. Currently, only one drug, albendazole is efficient to treat hookworm infection and the scientific community fears the rise of resistant strains. As part of on-going efforts to control hookworm infections and its associated morbidities, new drugs are urgently needed. We focused on targeting the blood-feeding pathway, which is essential to the parasite survival and reproduction, using the laboratory hookworm model Nippostrongylus brasiliensis (a nematode of rodents with a similar life cycle to hookworms). We established an in vitro-drug screening assay based on a fluorescent-based measurement of parasite viability during blood-feeding to identify novel therapeutic targets. A first screen of a library of 2654 natural compounds identified four that caused decreased worm viability in a blood-feeding-dependent manner. This new screening assay has significant potential to accelerate the discovery of new drugs against hookworms

    First experiences with Lu-177-PSMA-617 therapy for recurrent or metastatic salivary gland cancer

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    BACKGROUND: Advanced salivary gland cancers become difficult to treat when they are technically irresectable and radiotherapy limits are exceeded. There is also an unmet need to improve palliative systemic therapy. Salivary glands depict the Prostate-Specific Membrane Antigen (PSMA) on (68)Ga-PSMA-PET/CT, a transmembrane protein that is targeted for diagnosis and treatment of advanced prostate cancer. Some salivary gland carcinomas also express PSMA. METHODS: This study aimed to retrospectively evaluate the effectiveness of (177)Lu-PSMA-617 therapy for recurrent or metastatic salivary gland cancers, as a last resort treatment. Patients with serious tumour-related discomfort for whom no regular option was available were selected and critically re-assessed by the tumour board. Radionuclide therapy eligibility was confirmed when tumour targeting was greater than liver SUVmax on (68)Ga-PSMA-PET/CT. The protocol aimed at four cycles of 6.0–7.4 GBq (177)Lu-PSMA-617 every 6–8 weeks. Clinical response was evaluated by questionnaires and radiological response by (68)Ga-PSMA-PET/CT. RESULTS: Six patients were treated with (177)Lu-PSMA: four adenoid cystic carcinomas, one adenocarcinoma NOS and one acinic cell carcinoma. In two patients, radiological response was observed, showing either stable disease or a partial response, and four patients reported immediate relief of tumour-related symptoms. Most reported side effects were grade 1–2 fatigue, nausea, bone pain and xerostomia. Four patients prematurely discontinued therapy: three due to disease progression and one due to demotivating (grade 1) side-effects. CONCLUSIONS: Palliative (177)Lu-PSMA therapy for salivary gland cancer may lead to rapid relief of tumour-associated discomfort and may even induce disease stabilization. It is safe, relatively well tolerated and can be considered when regular treatment options fail

    Coulomb excitation of 68^{68}Ni at safe energies

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    The B(E2;0+2+)B(E2;0^+\to2^+) value in 68^{68}Ni has been measured using Coulomb excitation at safe energies. The 68^{68}Ni radioactive beam was post-accelerated at the ISOLDE facility (CERN) to 2.9 MeV/u. The emitted γ\gamma rays were detected by the MINIBALL detector array. A kinematic particle reconstruction was performed in order to increase the measured c.m. angular range of the excitation cross section. The obtained value of 2.81.0+1.2^{+1.2}_{-1.0} 102^2 e2^2fm4^4 is in good agreement with the value measured at intermediate energy Coulomb excitation, confirming the low 0+2+0^+\to2^+ transition probability.Comment: 4 pages, 5 figure
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