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Background: SMA is a neurodegenerative disease caused by biallelic deletion/mutation of SMN1. Copies of a similar gene (SMN2) modify disease severity. In a phase 1 study, SMN GRT onasemnogene abeparvovec (AVXS-101) improved outcomes of symptomatic SMA patients with two SMN2 copies (2xSMN2) dosed ≤6 months. Because motor neuron loss can be insidious and disease progression is rapid, early intervention is critical. This study evaluates AVXS-101 in presymptomatic SMA newborns. Methods: SPR1NT is a multicenter, open-label, phase 3 study enrolling ≥27 SMA patients with 2–3xSMN2. Asymptomatic infants ≤6 weeks receive a one-time intravenous AVXS-101 infusion (1.1x1014 vg/kg). Safety and efficacy are assessed through study end (18 [2xSMN2] or 24 months [3xSMN2]). Primary outcomes: independent sitting for ≥30 seconds (18 months [2xSMN2]) or assisted standing (24 months [3xSMN2]). Results: From April–September 2018, 7 infants received AVXS-101 (4 female; 6 with 2xSMN2) at ages 8–37 days. Mean baseline CHOP-INTEND score was 41.7 (n=6), which increased by 6.8, 11.0, 18.0, and 22.5 points at day 14 (n=4), month 1 (n=3), 2 (n=3), and 3 (n=2). Updated data available at the time of the congress will be presented. Conclusions: Preliminary data from SPR1NT show rapid motor function improvements in presymptomatic SMA patients.
Late Quaternary landscapes of unglaciated Beringia were largely shaped by ice-wedge polygon tundra. Ice Complex (IC) strata preserve such ancient polygon formations. Here we report on the Yukagir IC from Bol'shoy Lyakhovsky Island in northeastern Siberia and suggest that new radioisotope disequilibria (230Th/U) dates of the Yukagir IC peat confirm its formation during the Marine Oxygen Isotope Stage (MIS) 7a–c interglacial period. The preservation of the ice-rich Yukagir IC proves its resilience to last interglacial and late glacial–Holocene warming. This study compares the Yukagir IC to IC strata of MIS 5, MIS 3, and MIS 2 ages exposed on Bol'shoy Lyakhovsky Island. Besides high intrasedimental ice content and syngenetic ice wedges intersecting silts, sandy silts, the Yukagir IC is characterized by high organic matter (OM) accumulation and low OM decomposition of a distinctive Drepanocladus moss-peat. The Yukagir IC pollen data reveal grass-shrub-moss tundra indicating rather wet summer conditions similar to modern ones. The stable isotope composition of Yukagir IC wedge ice is similar to those of the MIS 5 and MIS 3 ICs pointing to similar atmospheric moisture generation and transport patterns in winter. IC data from glacial and interglacial periods provide insights into permafrost and climate dynamics since about 200 ka.
The reliability of energy dispersive x-ray fluorescence data for the analysis of low-alloy steels is reported for chromium, manganese, nickel, and molybdenum. The accuracy and precision of the analysis were evaluated for two mathematical models, linear and multiple regression, using twelve NBS standard reference samples. Data on results are furnished.
Early Archaic human skeletal remains found in a burial context in Lapa do
Santo in east-central Brazil provide a rare glimpse into the lives of
hunter-gatherer communities in South America, including their rituals for
dealing with the dead. These included the reduction of the body by means of
mutilation, defleshing, tooth removal, exposure to fire and possibly
cannibalism, followed by the secondary burial of the remains according to
strict rules. In a later period, pits were filled with disarticulated bones
of a single individual without signs of body manipulation, demonstrating
that the region was inhabited by dynamic groups in constant transformation
over a period of centuries.
The National Center for Disaster Medicine and Public Health (NCDMPH), in collaboration with over 20 subject matter experts, created a competency-based curriculum titled Caring for Older Adults in Disasters: A Curriculum for Health Professionals. Educators and trainers of health professionals are the target audience for this curriculum. The curriculum was designed to provide breadth of content yet flexibility for trainers to tailor lessons, or select particular lessons, for the needs of their learners and organizations. The curriculum covers conditions present in the older adult population that may affect their disaster preparedness, response, and recovery; issues related to specific types of disasters; considerations for the care of older adults throughout the disaster cycle; topics related to specific settings in which older adults receive care; and ethical and legal considerations. An excerpt of the final capstone lesson is included. These capstone activities can be used in conjunction with the curriculum or as part of stand-alone preparedness training. This article describes the development process, elements of each lesson, the content covered, and options for use of the curriculum in education and training for health professionals. The curriculum is freely available online at the NCDMPH website at http://ncdmph.usuhs.edu (Disaster Med Public Health Preparedness. 2016;10:633–637).
Sedimentary and magmatic rocks and their distinct sulphur isotopic signatures indicate the sources and processes of sulphur cycling, in particular through the analysis of all four stable sulphur isotopes (32S, 33S, 34S and 36S). Research over the past 15 years has substantially advanced our understanding of sulphur cycling on the early Earth, most notably through the discovery of mass-independently fractionated sulphur isotopic signatures. A strong atmospheric influence on the early Archean global sulphur cycle is apparent, much in contrast to the modern world. Diverse microbially driven sulphur cycling is clearly discernible, but its importance for Earth surface environments remains to be quantified.
Epitaxial layers of GaN on c-plane sapphire are analyzed by continuous-wave and time-resolved photoluminescence at 4K and by X-ray diffraction. Besides the well-known emissions from hexagonal GaN we observe luminescence bands at 3.279 and 3.15 to 3.21 eV which are identified as the transition of the donor bound exciton and the donor-acceptor pair recombination in cubic GaN, respectively. Measurements of the luminescence decay times are essential for the clarification of the emission processes. Due to the probing depth of about 200 nm in PL we find that the fraction of cubic phase typically decreases with layer thickness. In our best samples, however, we do not detect the cubic phase at all.
The objective of the present study was to compare the performance of seven different, widely applied crop models in predicting heat and drought stress effects. The study was part of a recent suite of model inter-comparisons initiated at European level and constitutes a component that has been lacking in the analysis of sources of uncertainties in crop models used to study the impacts of climate change. There was a specific focus on the sensitivity of models for winter wheat and maize to extreme weather conditions (heat and drought) during the short but critical period of 2 weeks after the start of flowering. Two locations in Austria, representing different agro-climatic zones and soil conditions, were included in the simulations over 2 years, 2003 and 2004, exhibiting contrasting weather conditions. In addition, soil management was modified at both sites by following either ploughing or minimum tillage. Since no comprehensive field experimental data sets were available, a relative comparison of simulated grain yields and soil moisture contents under defined weather scenarios with modified temperatures and precipitation was performed for a 2-week period after flowering. The results may help to reduce the uncertainty of simulated crop yields to extreme weather conditions through better understanding of the models’ behaviour. Although the crop models considered (DSSAT, EPIC, WOFOST, AQUACROP, FASSET, HERMES and CROPSYST) mostly showed similar trends in simulated grain yields for the different weather scenarios, it was obvious that heat and drought stress caused by changes in temperature and/or precipitation for a short period of 2 weeks resulted in different grain yields simulated by different models. The present study also revealed that the models responded differently to changes in soil tillage practices, which affected soil water storage capacity.
By examining the reflectance spectra of polycrystalline La1.85Sr0.15CuO4-y and La2NiO4-y in relation to the results of ir studies on single-crystal La2NiO4-y, we have determined the normal-state (room temperature) optical anisotropy of La1.85Sr0.15CuO4-y in the frequency range 40 cm-1 to 4800 cm-1. Vibrational and electronic properties corresponding to this anisotropy are examined, and a method is presented for extracting the optical properties of the superconducting state of La1.85Sr0.15CuO4-y.
Polarized Raman scattering spectra at 300K and 20K are reported for a single crystal of La2CuO4-y before and after annealing in oxygen at 1000°C for 24 hours. Oxygenation strongly quenches the temperature sensitive line at ∼1430 cm-1 (for T ∼ 300K) in the “as grown” crystal, previously identified with magnon-pair excitation associated with two-dimensional antiferromagnetic ordering. In addition, the phonon spectrum is greatly modified by the addition of oxygen, indicating a more uniform local crystalline environment after oxygenation. Raman scattering is thus a sensitive probe of the effect of oxygenation on the near surface magnetic and phonon properties of La2CuO4-y.
Pulsed laser ablation (PLA) has several characteristics that are potentially attractive for the growth and doping of chemically complex compound semiconductors including (1) stoichiometric (congruent) transfer of composition from target to film, (2) the use of reactive gases to control film composition and/or doping via energetic-beam-induced reactions, and (3) low-temperature nonequilibrium phase formation in the laser-generated plasma “plume.” However, the electrical properties of compound semiconductors are far more sensitive to low concentrations of defects than are the oxide metals/ceramics for which PLA has been so successful. Only recently have doped epitaxial compound semiconductor films been grown by PLA. Fundamental studies are being carried out to relate film electrical and microstructural properties to the energy distribution of ablated species, to the temporal evolution of the ablation pulse in ambient gases, and to beam-assisted surface and/or gas-phase reactions. In this paper we describe results of ex situ Hall effect, high-resolution x-ray diffraction, transmission electron microscopy, and Rutherford backscattering measurements that are being used in combination with in situ RHEED and time-resolved ion probe measurements to evaluate PLA for growth of doped epitaxial compound semiconductor films and heterostructures. Examples are presented and results analyzed for doped II–VI, I–III–VI, and column-Ill nitride materials grown recently in this and other laboratories.
Supermassive black holes (SMBHs) in the centers of massive galaxies are thought to predominantly grow in brief Eddington-rate quasar phases accompanied by starbursts, but on-going starbursts in luminous quasars are difficult to observe. Buried under the natural coronagraph, obscured quasars offer a unique window for direct, robust host-galaxy spectroscopy otherwise virtually inaccessible for luminous quasars. Our pilot study at z ~ 0.5 (Liu et al. 2009) revealed a substantial contribution from very young stellar populations with ages less than ~ 100 Myr in all of the observed host galaxy spectra. More dramatically, in three out of the nine SDSS quasars observed, we have witnessed strong infant starbursts with ages of ~ 5 Myr, clocked by the telltale Wolf–Rayet emission features.
Archean and Proterozoic time scales are currently defined chronometrically, with subdivisions into eras and periods being defined and allocated boundaries in terms of a round number of millions of years before present. Isotope stratigraphy is increasingly used to identify tectonic, chemical, and biological changes. The Neoproterozoic Era is characterized by at least two, and possibly four, severe and extensive glaciogenic events; for this era, chronostratigraphic subdivisions following established Phanerozoic practices are possible.
The “Precambrian” is not a formal stratigraphic term and simply refers to all rocks that formed prior to the beginning of the Cambrian Period. The task of establishing a rigorously defined and globally acceptable time scale for the Precambrian is an exceedingly difficult, and often frustrating, exercise. The reason for this is related to the fact that studying the Earth becomes increasingly difficult and uncertain the further one goes back in geological time.
The lack of a diverse and well-preserved fossil record, the generally decreasing volume of supracrustal rocks, and increasing degree of metamorphism and tectonic disturbance, as well as the uncertainties in the configuration and assembly of the continents, all contribute to making the establishment of a chronostratigraphic time scale beyond the Phanerozoic Eon problematical.
The Phanerozoic Eon broadly coincides with the most recent supercontinent cycle – a relatively well-understood sequence of geological events during which Pangea was assembled and dispersed.
We summarize the detection rates at wavelengths other than optical for ∼99,000 galaxies from the Sloan Digital Sky Survey (SDSS) Data Release 1 “main” spectroscopic sample. The analysis is based on positional cross-correlation with source catalogs from ROSAT, 2MASS, IRAS, GB6, FIRST, NVSS and WENSS surveys. We find that the rest-frame UV-IR broad-band galaxy SEDs form a remarkably uniform, nearly one parameter, family. As an example, the SDSS u and r band data, supplemented with redshift, can be used to predict K band magnitudes measured by 2MASS with an rms scatter of only 0.2 mag; when measurement uncertainties are taken into account, the astrophysical scatter appears not larger than ∼0.1 mag.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html
We analyze the properties of quasar variability using repeated SDSS imaging data in five UV-to-far red photometric bands, accurate to 0.02 mag, for ∼13,000 spectroscopically confirmed quasars. The observed time lags span the range from 3 hours to over 3 years, and constrain the quasar variability for rest-frame time lags of up to two years, and at rest-frame wavelengths from 1000Å to 6000Å. We demonstrate that ∼66,000 SDSS measurements of magnitude differences can be described within the measurement noise by a simple function of only three free parameters. The addition of POSS data constrains the long-term behavior of quasar variability and provides evidence for a turn-over in the structure function. This turn-over indicates that the characteristic time scale for optical variability of quasars is of the order 1 year.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html
Reduced, approximate MHD equations are derived for the case where
magnetic field is close to a potential field. The potential field can have
arbitrary three-dimensional structure, as long as it is non-vanishing.
current and pressure effects are included.
Background. In this study, we tested the hypothesis that low smooth pursuit gain in
schizophrenia is related to an abnormality in motion perception.
Methods. The subjects were 19 schizophrenics treated with clozapine and 19 controls. In addition
to smooth pursuit and motion perception paradigms, sustained attention was also assessed
using a continuous performance task (CPT).
Results. In the patient group, there was a statistically significant negative correlation between
smooth pursuit gain and motion perception threshold (r =−0·60, P<0·01). This relationship
was not secondary to attention deficits as assessed by the CPT.
Conclusions. Our results are consistent with the notion that the smooth pursuit gain deficit is
related to a deficit in motion perception rather than in attention. Brain area V5 (also referred to
as ‘MT’ in macaque), located in the parieto-occipital region, is known to be critically important
both for motion perception and gain. Thus, our results point to an abnormality in this area in
The increasing public attention paid to Supreme Court nominations has elevated the salience of Senate confirmation battles, raising interesting questions about the impact of constituency preferences on senators' voting behavior. In this article, we explore this relationship using a logistical regression model to examine the impacts of African-American constituency size and the proximity of reelection on the roll call behavior of senators on the Clarence Thomas confirmation vote. Our analyses indicate that these factors were both statistically and substantively significant in the Thomas case. We conclude by discussing the theoretical and practical implications of such findings.
The earlier collaborative project of the PPRG (1979–1980; Schopf 1983a) used a great deal of paper. As analytical work neared completion, handwritten “scoreboards” and “hit lists” were compiled to be sure that work proceeded efficiently and that important samples were not missed. As tables of results were prepared, extensive bibliographies were developed relating to stratigraphic relationships and sedimentary ages. Participants in the project reworded the accumulating paper like so many burrowing animals. When, for example, a decision was reached about the age to be estimated for a particular rock unit, multiple tabular entries had to be changed. Much communication focused on keeping the records straight rather than on questions of interpretation.
The “personal-computer revolution” preceded the beginning of the current PPRG project. Many of the researchers involved had already developed computerized databases, and it was resolved that the power and flexibility of this technology would be applied to the sample-tracking and information-management problems of PPRG. Three problem areas were identified: (i) construction of unified bibliographic database that could be searched and which could be used for preparation of the reference list for the final publication; (ii) management of the sample inventory and laboratory work; and (iii) compilation of results and related information. Systems were eventually developed in all of these areas as described briefly below. In spite of efforts at coordination, the degree of integration initially hoped for was not achieved, principally because the databases were, in their organization a well as contents, the result of individual efforts.