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Objectives: The aim of this study was to describe cognitive, academic, and psychosocial outcomes after an incident demyelinating event (acquired demyelinating syndromes, ADS) in childhood and to investigate the contribution of brain lesions and confirmed MS diagnosis on outcome. Methods: Thirty-six patients with ADS (mean age=12.2 years, SD=2.7, range: 7–16 years) underwent brain MRI scans at presentation and at 6-months follow-up. T2-weighted lesions on MRI were assessed using a binary classification. At 6-months follow-up, patients underwent neuropsychological evaluation and were compared with 42 healthy controls. Results: Cognitive, academic, and behavioral outcomes did not differ between the patients with ADS and controls. Three of 36 patients (8.3%) were identified with cognitive impairment, as determined by performance falling ≤1.5 SD below normative values on more than four independent tests in the battery. Poor performance on a visuomotor integration task was most common, observed among 6/32 patients, but this did not differ significantly from controls. Twelve of 36 patients received a diagnosis of MS within 3 years post-ADS. Patients with MS did not differ from children with monophasic ADS in terms of cognitive performance at the 6-months follow-up. Fatigue symptoms were reported in 50% of patients, irrespective of MS diagnosis. Presence of brain lesions at onset and 6 months post-incident demyelinating event did not associate with cognitive outcome. Conclusions: Children with ADS experience a favorable short-term neurocognitive outcome, even those confirmed to have MS. Longitudinal evaluations of children with monophasic ADS and MS are required to determine the possibility of late-emerging sequelae and their time course. (JINS, 2016, 22, 1050–1060)
Color centers in selected micro- and nanodiamond samples were investigated by cathodoluminescence (CL) microscopy and spectroscopy at 298 K [room temperature (RT)] and 77 K [liquid-nitrogen temperature (LNT)] to assess the value of the technique for astrophysics. Nanodiamonds from meteorites were compared with synthetic diamonds made with different processes involving distinct synthesis mechanisms (chemical vapor deposition, static high pressure high temperature, detonation). A CL emission peak centered at around 540 nm at 77 K was observed in almost all of the selected diamond samples and is assigned to the dislocation defect with nitrogen atoms. Additional peaks were identified at 387 and 452 nm, which are related to the vacancy defect. In general, peak intensity at LNT at the samples was increased in comparison to RT. The results indicate a clear temperature—dependence of the spectroscopic properties of diamond. This suggests the method is a useful tool in laboratory astrophysics.
In the context of life detection on terrestrial exoplanets, new methods of search for spectral signatures of chlorophyll and other biomarkers in the Earthshine have been developed in the last few decades. Astronomical observations made at OHP and ESO (NTT) showed a significant signal when continents are facing the Moon. This signal, called the Vegetation Red Edge (VRE), is undoubtedly due to chlorophyll absorption properties. In order to strengthen these results, the LUCAS (LUmière Cendrée en Antarctique par Spectroscopie) project dedicated to the measurement of the Earthshine from the Concordia Research Station (C Dome, Antarctica) has been set up. One of the objectives of LUCAS was to observe prolonged variations of the VRE corresponding to various parts of the Earth facing the Moon. An extension of this project, called LUCAS II, would allow long-term observations to detect seasonal variations of the vegetation signal. These data, together with accurate measurements of the Earth's albedo, will help validate a model of global and spectral albedo of our planet.
Nanowires with different nitrogen concentrations were grown by Metal-Organic Chemical Vapor Deposition (MOCVD) using DEZn, N2O and NH3as zinc, oxygen and nitrogen doping sources respectively. Low temperature photoluminescence, Raman spectroscopy and Transmission Electron Microscopy are combined to study the incorporation of nitrogen in the wires. The observation of donor-acceptor pair band confirms that the incorporation nitrogen in ZnO nanowires is responsible for the creation of acceptor centers. The additional peaks observed in Raman are correlated to nano-sized inter-atomic distance fluctuations observed in TEM. These domains combined with a resonance effect are probably the explanation of the huge Raman cross section observed for the impurity related peaks.
Studies using 24 h urine collections need to incorporate ways to validate the completeness of the urine samples. Models to predict urinary creatinine excretion (UCE) have been developed for this purpose; however, information on their usefulness to identify incomplete urine collections is limited. We aimed to develop a model for predicting UCE and to assess the performance of a creatinine index using para-aminobenzoic acid (PABA) as a reference. Data were taken from the European Food Consumption Validation study comprising two non-consecutive 24 h urine collections from 600 subjects in five European countries. Data from one collection were used to build a multiple linear regression model to predict UCE, and data from the other collection were used for performance testing of a creatinine index-based strategy to identify incomplete collections. Multiple linear regression (n 458) of UCE showed a significant positive association for body weight (β = 0·07), the interaction term sex × weight (β = 0·09, reference women) and protein intake (β = 0·02). A significant negative association was found for age (β = − 0·09) and sex (β = − 3·14, reference women). An index of observed-to-predicted creatinine resulted in a sensitivity to identify incomplete collections of 0·06 (95 % CI 0·01, 0·20) and 0·11 (95 % CI 0·03, 0·22) in men and women, respectively. Specificity was 0·97 (95 % CI 0·97, 0·98) in men and 0·98 (95 % CI 0·98, 0·99) in women. The present study shows that UCE can be predicted from weight, age and sex. However, the results revealed that a creatinine index based on these predictions is not sufficiently sensitive to exclude incomplete 24 h urine collections.
The aim of the LUCAS program is to observe chlorophyll and atmospheric molecules in the Earthshine spectrum in order to prepare the detection of life in terrestrial extrasolar planets to be discovered. Actually, observations from Antarctica offer a unique possibility to study the variations of Earthshine spectrum during Earth rotation while various parts of Earth are facing the Moon. Special instrumentation for the LUCAS program was designed and put in the Concordia station in the Dome C. Observations are in progress.
Division II provides a forum for astronomers studying a wide range of problems related to the structure, radiation and activity of the Sun, and its interaction with the Earth and the rest of the solar system.
The search for life in extraterrestrial planets is to be tested first with the only planet known to shelter life. If the planet Earth is used as an example to search for a signature of life, the vegetation is one of its possible detectable signature, using the Vegetation Red Edge due to chlorophyll in the near infrared (0.725 μm). We focus on the test of the detectability of vegetation in the spectrum of Earth seen as a simple dot, using the reflection of the global Earth on the lunar surface, i.e., Earthshine. On the Antartic, the Earthshine can be seen during several hours in a day (not possible at our latitudes) and so variations due to different parts of Earth, that is to say oceans and continents facing the Moon could be detected.
Division II of the IAU provides a forum for astronomers studying a wide range of phenomena related to the structure, radiation and activity of the Sun, and its interaction with the Earth and the rest of the solar system. Division II encompasses three Commissions, 10, 12 and 49, and four working groups. During the last triennia the activities of the division involved some reorganization of the division and its working groups, developing new procedures for election of division and commission officers, promoting annual meetings from within the division and evaluating all the proposed meetings, evaluating the division's representatives for the IAU to international scientific organizations, and participating in general IAU business.
Results are presented of radiocarbon and tritium measurements along a transect between the Australian continental shelf and the Indonesian coast of Bali. The stations lie in the easternmost part of the Indian Ocean, close to the sills over which the Indonesian throughflow (ITF) makes its way to the Indian Ocean. The present data, obtained as part of the Java-Australia Dynamics Experiment (JADE) in August 1989, complement the WOCE 14C and tritium data set on both sides of the Indonesian archipelago and give us the opportunity to discuss the origin of the water masses and timescale of the throughflow. Both tracers point to a north equatorial Pacific origin of the waters. The comparison of the tritium inventories in the Pacific North Equatorial Current and along the JADE transect suggests a minimum transit time of the waters across the Indonesian seaways of the order of 5 to 6 yr, corresponding to a throughflow <18 × 106 m3/s.
IN RECENT TIMES, the covert yet insistent relation between aesthetics and political economy has claimed significant critical focus, for these two discourses have implicated and complicated each other in puzzling ways.1 In offering some background to this relation, Mary Poovey has traced the modern history of aesthetics and political economy to a common origin within the eighteenth-century field of moral philosophy.2 As a study in search of cultural cohesion, moral philosophy drew together a wide-ranging set of critiques including ethics, aesthetics, economics, and government. Then, in the second half of the eighteenth century, the field branched, Poovey tells us, shaping new categories of knowledge through such works as Edmund Burke’s Enquiry (1757) on aesthetics and Adam Smith’s Wealth of Nations (1776) on political economy. As these divisions in knowledge became further refined through discursive practice in the Victorian Age, aesthetics and political economy appeared to have little to do with each other; however, Poovey argues that “one way to remember the originary relationship between these two discourses — and to measure the toll exacted by their division — is to tease from each its past and present entanglements with gender” (“Aesthetics” 8). In this essay, I take up her call by examining the relation between aesthetics and political economy, as they inscribe their mediations on gender roles in George Eliot’s Middlemarch.
Accelerator mass spectrometry (AMS) radiocarbon measurements were made on 120 samples collected between Antarctica and South Africa along 30°E during the WOCE-France CIVA1 campaign in February 1993. Our principal objective was to complement the Southern Ocean's sparse existing data set in order to improve the 14C benchmark used for validating ocean carbon-cycle models, which disagree considerably in this region. Measured 14C is consistent with the θ-S characteristics of CIVA1. Antarctic Intermediate Water (AAIW) forming north of the Polar Front (PF) is rich in 14C, whereas surface waters south of the PF are depleted in 14C. A distinct old 14C signal was found for the contribution of the Pacific Deep Water (PDW) to the return flow of Circumpolar Deep Waters (CDW). Comparison to previous measurements shows a 14C decrease in surface waters, consistent with northward displacement of surface waters, replacement by old deep waters upwelled at the Antarctic Divergence, and atmospheric decline in 14C. Conversely, an increase was found in deeper layers, in the AAIW. Large uncertainties, associated with previous methods for separating natural and bomb 14C when in the Southern Ocean south of 45°S, motivated us to develop a new approach that relies on a simple mixing model and on chlorofluorocarbon (CFC) measurements also taken during CIVA1. This approach leads to inventories for CIVA1 that are equal to or higher than those calculated with previous methods. Differences between old and new methods are especially high south of approximately 55°S, where bomb 14C inventories are relatively modest.
A 4.5-m-thick late-glacial pollen sequence, supported by 17 AMS 14C dates, has been investigated at the Quintanar de la Sierra marshland (Iberian cordillera, north-central Spain). Pollen zones were defined that correspond to successive phases in vegetation history during the end of the Late Würm, late-glacial interstade, and Younger Dryas periods. A transfer function approach has been adopted to derive quantitative climate estimates from the pollen assemblage data. A first expansion ofJuniperus and Hippophae, about 13,500 14C yr B.P., indicates the beginning of the late-glacial interstade which is characterized by a Juniperus–Betula–Pinus succession that suggests higher temperatures and moisture than during full-glacial time. The Younger Dryas interval is recorded by a 120-cm-thick sediment unit that is dominated by herbaceous pollen. Transfer function estimates suggest that the climate during this period was cold, with low precipitation during most of the year, although not in summer. The Holocene arboreal recolonization in the area started about 10,000 14C yr B.P., with a renewed Juniperus–Betula–Pinus succession related to a strong increase in annual temperature and precipitation. The start of this process was synchronous with mean sea-surface temperature changes, as recorded from the nearby SU 81-18 marine core. The strong affinity with other European late-glacial pollen sequences demonstrates that the pattern of climatic changes during the last glacial–interglacial transition was similar in both northwestern and southwestern Europe.
This paper is a comprehensive review of the state-of-knowledge in the field of radiation effects in glasses that are to be used for the immobilization of high-level nuclear waste and plutonium disposition. The current status and issues in the area of radiation damage processes, defect generation, microstructure development, theoretical methods and experimental methods are reviewed. Questions of fundamental and technological interest that offer opportunities for research are identified.
Further work inside the Grotte Cosquer, the Palaeolithic painted cave near Marseilles only accessible by a deep-water dive, improves our knowledge and makes it clear there can be no artificial entrance made to create a dry-land access.
Morphometric analyses show quantitative differences in anatomical characters of wood and charcoal between wild and cultivated olive. Samples from modern olive wood in eastern Spain (Levante) provide five distinctive anatomical criteria: growth width ring, vessel surface, number of vessels per group, vessel density, and vulnerability ratio. Multivariate analysis shows that growth ring width and number of vessels per group are both significant criteria for discriminating between wild and cultivated olive. Moreover, bioclimatic environments of wild olive (thermomediterranean and mesomediterranean stages) are distinguished by vessel density. Ancient olive charcoal from archaeological sites at Valencia and Alicante implies increasing aridification from the Cardial Neolithic to the Roman Period. This pattern may reflect the onset of a Mediterranean climate and human deforestation. Charcoal from cultivated specimens of early Neolithic age shows that the olive tree is the earliest cultivated temperate fruit.
Ripgut brome has a quantitative response to vernalization in relation to flowering. In greenhouse studies, cold treatment (5 ± 2 C) of 2, 4, or 6 wk shortened the vegetative period, but longer exposure did not further decrease the time required to flower. Plants vernalized as imbibed seeds for 8 wk took 17 d to flower following transfer from cold treatment to the greenhouse. Unvernalized controls flowered 53 d after planting in the greenhouse. Greatest total seed dry weight and vegetative shoot dry weight were produced by unvernalized plants, whereas lengthening periods of vernalization from 2 to 8 wk decreased both parameters. The percent of total seed dry weight to total shoot dry weight was significantly greater for vernalized plants than unvernalized controls. In field studies, ripgut brome plants established in the fall flowered sooner after resumption of growth in the spring than those planted in the spring. Plants seeded after April failed to flower until the following spring.