827 research outputs found

    Memory for serial order in bilingual children

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    Poster: no. 10Recent studies have suggested that phonological short-term memory (STM) capacity is important for language acquisition. In both, children and grownups, reliable correlations have been obtained between digit span, nonword repetition ability, and vocabulary achievement while factoring out other possible factors like age and nonverbal intelligence (Gathercole, Service, Hitch, Adams, & Martin, 1999; Gathercole, Willis, Emslie, & Baddeley, 1992; Gupta, 2003). Majerus et al. (Majerus, Poncelet, Van der Linden, & Weekes, 2008) found that serial order memory was the most important predictor for new word learning. No evidence was found for item short-term memory as a predictor. Majerus et al. therefore suggested that order short-term memory and phonological awareness are independent predictors of new word learning. Our aim was to investigate the memory for serial order in mono- and bilingual language processing to elicit ERP correlates of item and order STM, during encoding, maintenance and retrieval stages. 25 monolingual native English speakers …postprintThe International Conference on Neurobilingualism, Bangor University, Wales, U.K., 19-20 September 2009

    Four methods for determining the composition of trace radioactive surface contamination of low-radioactivity metal

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    Four methods for determining the composition of low-level uranium- and thorium-chain surface contamination are presented. One method is the observation of Cherenkov light production in water. In two additional methods a position-sensitive proportional counter surrounding the surface is used to make both a measurement of the energy spectrum of alpha particle emissions and also coincidence measurements to derive the thorium-chain content based on the presence of short-lived isotopes in that decay chain. The fourth method is a radiochemical technique in which the surface is eluted with a weak acid, the eluate is concentrated, added to liquid scintillator and assayed by recording beta-alpha coincidences. These methods were used to characterize two `hotspots' on the outer surface of one of the He-3 proportional counters in the Neutral Current Detection array of the Sudbury Neutrino Observatory experiment. The methods have similar sensitivities, of order tens of ng, to both thorium- and uranium-chain contamination.Comment: 22 pages, 19 figure

    A beta-alpha coincidence counting system for measurement of trace quantities of 238U and 232Th in aqueous samples at the Sudbury Neutrino Observatory

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    The Sudbury Neutrino Observatory experiment was built to measure the total flux of 8B solar neutrinos via the neutral current disintegration deuterium nuclei. This process can be mimicked by daughter isotopes of 232Th and 238U which can photo-disintegrate the deuterium nucleus. Measurement of the concentration of such radioisotopes in the heavy water was critical to the success of the experiment. A radium assay technique using Hydrous Titanium Oxide coated filters was developed for this purpose and it was used in conjunction with a delayed beta-alpha coincidence counting system. The design, calibration and operation of this counting system are described in this paper. The counting efficiency for 232Th (224Ra) and 238U (226Ra) were measured to be 50 +/- 5% and 62 +/- 7

    Visual fixation in the vegetative state: an observational case series PET study

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    BACKGROUND: Assessment of visual fixation is commonly used in the clinical examination of patients with disorders of consciousness. However, different international guidelines seem to disagree whether fixation is compatible with the diagnosis of the vegetative state (i.e., represents "automatic" subcortical processing) or is a sufficient sign of consciousness and higher order cortical processing. METHODS: We here studied cerebral metabolism in ten patients with chronic post-anoxic encephalopathy and 39 age-matched healthy controls. Five patients were in a vegetative state (without fixation) and five presented visual fixation but otherwise showed all criteria typical of the vegetative state. Patients were matched for age, etiology and time since insult and were followed by repeated Coma Recovery Scale-Revised (CRS-R) assessments for at least 1 year. Sustained visual fixation was considered as present when the eyes refixated a moving target for more than 2 seconds as defined by CRS-R criteria. RESULTS: Patients without fixation showed metabolic dysfunction in a widespread fronto-parietal cortical network (with only sparing of the brainstem and cerebellum) which was not different from the brain function seen in patients with visual fixation. Cortico-cortical functional connectivity with visual cortex showed no difference between both patient groups. Recovery rates did not differ between patients without or with fixation (none of the patients showed good outcome). CONCLUSIONS: Our findings suggest that sustained visual fixation in (non-traumatic) disorders of consciousness does not necessarily reflect consciousness and higher order cortical brain function

    High sensitivity measurement of 224Ra and 226Ra in water with an improved hydrous titanium oxide technique at the Sudbury Neutrino Observatory

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    The existing hydrous titanium oxide (HTiO) technique for the measurement of 224Ra and 226Ra in the water at the Sudbury Neutrino Observatory (SNO) has been changed to make it faster and less sensitive to trace impurities in the HTiO eluate. Using HTiO-loaded filters followed by cation exchange adsorption and HTiO co-precipitation, Ra isotopes from 200-450 tonnes of heavy water can be extracted and concentrated into a single sample of a few millilitres with a total chemical efficiency of 50%. Combined with beta-alpha coincidence counting, this method is capable of measuring 2.0x10^3 uBq/kg of 224Ra and 3.7x10^3 uBq/kg of 226Ra from the 232Th and 238U decay chains, respectively, for a 275 tonne D2O assay, which are equivalent to 5x10^16 g Th/g and 3x10^16 g U/g in heavy water.Comment: 8 Pages, 2 figures and 2 table

    PAJAK BUMI DAN BANGUNAN SEBAGAI INSTRUMEN KEMASLAHATAN UMAT DALAM PERSPEKTIF EKONOMI ISLAM

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    ABSTRAK Skripsi dengan judul “Pajak Bumi Dan Bangunan sebagai Instrumen Kemaslahatan Umat dalam Perspektif Ekonomi Islam” ini ditulis oleh Hasna Jannatu Zuhriya, NIM. 2824133036, pembimbing Nur Aziz Muslim, M. HI. Penelitian ini dilatar belakangi dengan adanya dana pembiayaan pembangunan negara yang antara lain bersumber dari pajak yang salah satunya adalah Pajak Bumi dan Bangunan. Strategisnya Pajak Bumi dan Bangunan objeknya meliputi seluruh bumi dan bangunan yang berada dalam wilayah Negara Kesatuan Republik Indonesia. Melihat sejarah awal negara Islam yang dipimpin oleh Nabi Muhammad Saw, Khulafaur Rasyidin dan seterusnya dalam menjalankan roda pemerintahan memerlukan adanya pendapatan, yaitu yang bersumber dari zakat, jizyah, kharaj, ghanimah, fai’ dan lainnya yang merupakan sumber pendapatan pada masa itu. Dalam bidang ekonomi Islam, pajak dapat mencegah penumpukan harta kekayaan dan menciptakan pendistribusian kekayaan kepada masyarakat. Sehingga dapat mendukung tercapainya kemaslahatan umat. Rumusan masalah dalam penelitian ini adalah: (1) Apakah pajak dibolehkan dari sisi ekonomi Islam? (2) Apakah pajak bumi dan bangunan dibolehkan dari sisi ekonomi Islam? (3) Apakah objek pajak bumi dan bangunan sesuai dengan konsep distribusi kekayaan dalam ekonomi Islam? (4) Apakah tarif pajak bumi dan bangunan sesuai dengan prinsip kemaslahatan dalam ekonomi Islam? Tujuan dalam penelitian ini adalah: (1) mendeskripsikan apakah pajak dibolehkan dari sisi ekonomi Islam. (2) mendeskripsikan apakah pajak bumi dan bangunan dibolehkan dari sisi ekonomi Islam. (3) mendeskripsikan apakah objek pajak bumi dan bangunan sesuai dengan konsep distribusi kekayaan dalam ekonomi Islam. (4) mendeskripsikan apakah tarif pajak bumi dan bangunan sesuai dengan prinsip kemaslahatan dalam ekonomi Islam. Dalam penelitian ini menggunakan metode penelitian kepustakaan, yaitu penelitian yang data dan informasinya diperoleh dari sumber pustaka (bacaan) baik berupa buku-buku, hasil penelitian, dan bahan bacaan yang lainnya. Sumber data yang digunakan adalah sumber skunder. Dengan menggunakan metode analisis deduktif. Dari hasil penelitian ini dapat disimpulkan bahwa: (1) Dalam ekonomi Islam, pajak termasuk sistem distribusi kekayaan. (2) Dengan prinsip untuk menciptakan kemaslahatan umum, PBB boleh dikenakan pada orang yang kaya sebagaimana prinsip maslahah mursalah. (3) Objek pajak bumi dan bangunan sesuai dengan konsep distribusi kekayaan dalam ekonomi Islam. (4) Sistem tarif pajak bumi dan bangunan yang ditetapkan telah memenuhi kriteria adil (kemaslahatan) dalam ekonomi Islam. Kata kunci: Pajak, Pajak Bumi dan Bangunan, Kemaslahatan Umat, dan Ekonomi Islam

    Measurement of 222Rn dissolved in water at the Sudbury Neutrino Observatory

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    The technique used at the Sudbury Neutrino Observatory (SNO) to measure the concentration of 222Rn in water is described. Water from the SNO detector is passed through a vacuum degasser (in the light water system) or a membrane contact degasser (in the heavy water system) where dissolved gases, including radon, are liberated. The degasser is connected to a vacuum system which collects the radon on a cold trap and removes most other gases, such as water vapor and nitrogen. After roughly 0.5 tonnes of H2O or 6 tonnes of D2O have been sampled, the accumulated radon is transferred to a Lucas cell. The cell is mounted on a photomultiplier tube which detects the alpha particles from the decay of 222Rn and its daughters. The overall degassing and concentration efficiency is about 38% and the single-alpha counting efficiency is approximately 75%. The sensitivity of the radon assay system for D2O is equivalent to ~3 E(-15) g U/g water. The radon concentration in both the H2O and D2O is sufficiently low that the rate of background events from U-chain elements is a small fraction of the interaction rate of solar neutrinos by the neutral current reaction.Comment: 14 pages, 6 figures; v2 has very minor change

    Diagnostic accuracy of the vegetative and minimally conscious state: Clinical consensus versus standardized neurobehavioral assessment

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    BACKGROUND: Previously published studies have reported that up to 43% of patients with disorders of consciousness are erroneously assigned a diagnosis of vegetative state (VS). However, no recent studies have investigated the accuracy of this grave clinical diagnosis. In this study, we compared consensus-based diagnoses of VS and MCS to those based on a well-established standardized neurobehavioral rating scale, the JFK Coma Recovery Scale-Revised (CRS-R). METHODS: We prospectively followed 103 patients (55 +/- 19 years) with mixed etiologies and compared the clinical consensus diagnosis provided by the physician on the basis of the medical staff's daily observations to diagnoses derived from CRS-R assessments performed by research staff. All patients were assigned a diagnosis of 'VS', 'MCS' or 'uncertain diagnosis.' RESULTS: Of the 44 patients diagnosed with VS based on the clinical consensus of the medical team, 18 (41%) were found to be in MCS following standardized assessment with the CRS-R. In the 41 patients with a consensus diagnosis of MCS, 4 (10%) had emerged from MCS, according to the CRS-R. We also found that the majority of patients assigned an uncertain diagnosis by clinical consensus (89%) were in MCS based on CRS-R findings. CONCLUSION: Despite the importance of diagnostic accuracy, the rate of misdiagnosis of VS has not substantially changed in the past 15 years. Standardized neurobehavioral assessment is a more sensitive means of establishing differential diagnosis in patients with disorders of consciousness when compared to diagnoses determined by clinical consensus
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