101 research outputs found
Measurements of the band gap of ThF4 by electron spectroscopy techniques
We present an experimental determination of the band gap of ThF4 performed by two different techniques.
The first measurement was performed by combining x-ray photoemission spectroscopy and bremsstrahlung
isochromat spectroscopy. The second measurement exploited the position of the inelastic threshold in reflection
electron energy loss spectroscopy. Both measurements gave compatible values of the band gap, with the average
E = 10.2(2) eV. This value was found to be in excellent agreement with theoretical calculations. The measured
band gap is significantly larger than the 229mTh excitation energy, making ThF4 a possible candidate material for
a solid-state nuclear clock based on the vacuum ultraviolet \u3b3 decay
Multiplet effects in the electronic structure of -Pu, Am and their compounds
We propose a straightforward and efficient procedure to perform dynamical
mean-field (DMFT) calculations on the top of the static mean-field LDA+U
approximation. Starting from self-consistent LDA+U ground state we included
multiplet transitions using the Hubbard-I approximation, which yields a very
good agreement with experimental photoelectron spectra of -Pu, Am, and
their selected compounds.Comment: submitted to Europhysics Letter
Nature of non-magnetic strongly-correlated state in delta-plutonium
Ab-initio relativistic dynamical mean-field theory is applied to resolve the
long-standing controversy between theory and experiment in the "simple"
face-centered cubic phase of plutonium called delta-Pu. In agreement with
experiment, neither static nor dynamical magnetic moments are predicted. In
addition, the quasiparticle density of states reproduces not only the peak
close to the Fermi level, which explains the large coefficient of electronic
specific heat, but also main 5f features observed in photoelectron
spectroscopy.Comment: 9 pages, 3 figure
CNTN6 mutations are risk factors for abnormal auditory sensory perception in autism spectrum disorders
Contactin genes CNTN5 and CNTN6 code for neuronal cell adhesion molecules that promote neurite outgrowth in sensory-motor neuronal pathways. Mutations of CNTN5 and CNTN6 have previously been reported in individuals with autism spectrum disorders (ASDs), but very little is known on their prevalence and clinical impact. In this study, we identified CNTN5 and CNTN6 deleterious variants in individuals with ASD. Among the carriers, a girl with ASD and attention-deficit/hyperactivity disorder was carrying five copies of CNTN5. For CNTN6, both deletions (6/1534 ASD vs 1/8936 controls; P=0.00006) and private coding sequence variants (18/501 ASD vs 535/33480 controls; P=0.0005) were enriched in individuals with ASD. Among the rare CNTN6 variants, two deletions were transmitted by fathers diagnosed with ASD, one stop mutation CNTN6W923X was transmitted by a mother to her two sons with ASD and one variant CNTN6P770L was found de novo in a boy with ASD. Clinical investigations of the patients carrying CNTN5 or CNTN6 variants showed that they were hypersensitive to sounds (a condition called hyperacusis) and displayed changes in wave latency within the auditory pathway. These results reinforce the hypothesis of abnormal neuronal connectivity in the pathophysiology of ASD and shed new light on the genes that increase risk for abnormal sensory perception in ASD
BUILDING BRIDGES FOR INNOVATION IN AGEING : SYNERGIES BETWEEN ACTION GROUPS OF THE EIP ON AHA
The Strategic Implementation Plan of the European Innovation Partnership on Active and Healthy Ageing (EIP on AHA) proposed six Action Groups. After almost three years of activity, many achievements have been obtained through commitments or collaborative work of the Action Groups. However, they have often worked in silos and, consequently, synergies between Action Groups have been proposed to strengthen the triple win of the EIP on AHA. The paper presents the methodology and current status of the Task Force on EIP on AHA synergies. Synergies are in line with the Action Groups' new Renovated Action Plan (2016-2018) to ensure that their future objectives are coherent and fully connected. The outcomes and impact of synergies are using the Monitoring and Assessment Framework for the EIP on AHA (MAFEIP). Eight proposals for synergies have been approved by the Task Force: Five cross-cutting synergies which can be used for all current and future synergies as they consider overarching domains (appropriate polypharmacy, citizen empowerment, teaching and coaching on AHA, deployment of synergies to EU regions, Responsible Research and Innovation), and three cross-cutting synergies focussing on current Action Group activities (falls, frailty, integrated care and chronic respiratory diseases).Peer reviewe
Neuroprotection by adenosine in the brain: From A1 receptor activation to A2A receptor blockade
Adenosine is a neuromodulator that operates via the most abundant inhibitory adenosine A1 receptors (A1Rs) and the less abundant, but widespread, facilitatory A2ARs. It is commonly assumed that A1Rs play a key role in neuroprotection since they decrease glutamate release and hyperpolarize neurons. In fact, A1R activation at the onset of neuronal injury attenuates brain damage, whereas its blockade exacerbates damage in adult animals. However, there is a down-regulation of central A1Rs in chronic noxious situations. In contrast, A2ARs are up-regulated in noxious brain conditions and their blockade confers robust brain neuroprotection in adult animals. The brain neuroprotective effect of A2AR antagonists is maintained in chronic noxious brain conditions without observable peripheral effects, thus justifying the interest of A2AR antagonists as novel protective agents in neurodegenerative diseases such as Parkinson’s and Alzheimer’s disease, ischemic brain damage and epilepsy. The greater interest of A2AR blockade compared to A1R activation does not mean that A1R activation is irrelevant for a neuroprotective strategy. In fact, it is proposed that coupling A2AR antagonists with strategies aimed at bursting the levels of extracellular adenosine (by inhibiting adenosine kinase) to activate A1Rs might constitute the more robust brain neuroprotective strategy based on the adenosine neuromodulatory system. This strategy should be useful in adult animals and especially in the elderly (where brain pathologies are prevalent) but is not valid for fetus or newborns where the impact of adenosine receptors on brain damage is different
Inventory of current EU paediatric vision and hearing screening programmes
Background: We examined the diversity in paediatric vision and hearing screening
programmes in Europe.
Methods: Themes relevant for comparison of screening programmes were derived from
literature and used to compile three questionnaires on vision, hearing and public-health
screening. Tests used, professions involved, age and frequency of testing seem to influence
sensitivity, specificity and costs most. Questionnaires were sent to ophthalmologists,
orthoptists, otolaryngologists and audiologists involved in paediatric screening in all EU fullmember,
candidate and associate states. Answers were cross-checked.
Results: Thirty-nine countries participated; 35 have a vision screening programme, 33 a
nation-wide neonatal hearing screening programme. Visual acuity (VA) is measured in 35
countries, in 71% more than once. First measurement of VA varies from three to seven years
of age, but is usually before the age of five. At age three and four picture charts, including Lea
Hyvarinen are used most, in children over four Tumbling-E and Snellen. As first hearing
screening test otoacoustic emission (OAE) is used most in healthy neonates, and auditory
brainstem response (ABR) in premature newborns. The majority of hearing testing
programmes are staged; children are referred after one to four abnormal tests. Vision
screening is performed mostly by paediatricians, ophthalmologists or nurses. Funding is
mostly by health insurance or state. Coverage was reported as >95% in half of countries, but
reporting was often not first-hand.
Conclusion: Largest differences were found in VA charts used (12), professions involved in
vision screening (10), number of hearing screening tests before referral (1-4) and funding
sources (8)
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