139 research outputs found
Some Mean-Value Theorems of the Cauchy Type
2000 Mathematics Subject Classification: Primary 26A24, 26D15; Secondary 41A05Some mean-value theorems of the Cauchy type, which are connected
with Jensenâs inequality, are given in [2] in discrete form and in [5] in integral
form. Several further generalizations and applications of these results are
presented here
Carboplatin-Induced Bilateral Papilledema: A Case Report
We report on a patient with carboplatin-induced bilateral papilledema, as it was described in the 1970s for cisplatin. Loss of visual accuracy up to full blindness, often loss of color vision and scotomas can be seen as a result of cortical blindness, macula degeneration, retrobulbar neuritis and papilledema. These symptoms are mostly unilateral and initially mild, so that more chemotherapy is given before the diagnosis is made. The symptoms are usually reversible within weeks to months after cessation of the platinum treatment. The therapeutic strategy is stopping the platinum treatment. In addition the empiric use of corticosteroids is suggested
Genetic and environmental underpinnings of spatial abilities and their role in predicting academic achievement and success in STEM
Behavior Genetics Association 45th Annual Meeting Abstract:
Spatial abilities encompass several factors that are differentiable from general cognitive ability (intelligence). Importantly, spatial abilities have been shown to be significant predictors of many life outcomes, even after controlling for intelligence. Quantitative genetic studies have shown that diverse measures of spatial ability are moderately heritable (30â50 %), although some important aspects of spatial ability such as navigation and map-reading have been neglected. Little is known about the factor structure of spatial measures or their links with academic achievement, especially STEM subjects (science, technology, engineering, mathematics). For these reasons, we launched a program of research creating novel online gamified measures of diverse spatial abilities including mental rotation, spatial visualization, spatial scanning, navigation, and map-reading. We piloted the measures on 100 unrelated individuals; all measures produced good testâretest reliability (0.7 on average). The battery was administered online to 1000 twin pairs (age 19â21) from the UK representative Twins Early Development Study (TEDS). Phenotypically, the results provided some evidence for the multifactorial nature of spatial ability, independent of intelligence, despite substantial correlations among the factors. Univariate genetic analyses yielded moderate heritability for all tests and factors. One of the most interesting findings was that these spatial factors correlated with success in STEM subjects, especially with achievement in mathematics, even after controlling for intelligence, and genetic factors largely accounted for these phenotypic associations TEDS is supported by a program grant to RP from the UK Medical Research Council [G0901245; and previously G0500079], with additional support from the US National Institutes of Health [HD044454; HD059215]. NS and KR are supported by Medical Research Council
The effect of surface preparation on the protective properties of Al2O3 and HfO2 thin films deposited on cp-titanium by atomic layer deposition
Atomic layer deposition (ALD), a method that allows the formation of thin and conformal films on substrates of interest, was employed to prepare thin films of alumina (Al2O3) and hafnia (HfO2), with the aim of protecting the surface of the commercially pure titanium (cp-Ti) used in biomedical applications. Prior to deposition, cp-Ti specimens have been prepared in two ways \u2013 grinding and grinding followed by polishing. Such surfaces have been denoted as rough and smooth, respectively. The thickness, composition, morphology and topography of alumina and hafnia films have been determined using ellipsometry, focused ion beam microscopy with energy dispersive X-ray spectroscopy, time-of-flight secondary ion mass spectrometry and 3D profilometry. A homogeneous stoichiometric composition of alumina and hafnia was obtained with a layer thickness of ca. 150 nm. The anti-corrosive properties of ALD thin films were measured in simulated body fluid solution, using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization curves. The roughness of the cp-Ti surface plays an important role in the protective properties of these films, especially those of hafnia. In general, when deposited on a smooth surface, ALD films with better anti-corrosive properties were obtained, as evidenced by EIS long-term, 40-day tests. ALD films showed very low porosity, calculated from electrochemical parameters, and significantly lower corrosion current densities, compared with those from bare cp-Ti specimens. Lower porosity and slightly better protective properties were provided by films of hafnia. On the other hand, according to EIS long-term tests, alumina retained slightly greater impedance values than hafnia. Since both alumina and hafnia are biocompatible materials, this study confirms the possibility of their use to reduce the risk of failure of medical implants made of cp-Ti, in the human body environment
Implementation and performance of SIBYLS: a dual endstation small-angle X-ray scattering and macromolecular crystallography beamline at the Advanced Light Source.
The SIBYLS beamline (12.3.1) of the Advanced Light Source at Lawrence Berkeley National Laboratory, supported by the US Department of Energy and the National Institutes of Health, is optimized for both small-angle X-ray scattering (SAXS) and macromolecular crystallography (MX), making it unique among the world's mostly SAXS or MX dedicated beamlines. Since SIBYLS was commissioned, assessments of the limitations and advantages of a combined SAXS and MX beamline have suggested new strategies for integration and optimal data collection methods and have led to additional hardware and software enhancements. Features described include a dual mode monochromator [containing both Si(111) crystals and Mo/B(4)C multilayer elements], rapid beamline optics conversion between SAXS and MX modes, active beam stabilization, sample-loading robotics, and mail-in and remote data collection. These features allow users to gain valuable insights from both dynamic solution scattering and high-resolution atomic diffraction experiments performed at a single synchrotron beamline. Key practical issues considered for data collection and analysis include radiation damage, structural ensembles, alternative conformers and flexibility. SIBYLS develops and applies efficient combined MX and SAXS methods that deliver high-impact results by providing robust cost-effective routes to connect structures to biology and by performing experiments that aid beamline designs for next generation light sources
Global Waste Management Outlook
The Global Waste Management Outlook, a collective effort of the United Nations Environment Programme and the International Waste Management Association, is a pioneering scientific global assessment on the state of waste management and a call for action to the international community. Prepared as a follow up to the Rio+20 Summit and as a response to UNEP Governing Council decision GC 27/12, the document establishes the rationale and the tools for taking a holistic approach towards waste management and recognizing waste and resource management as a significant contributor to sustainable development and climate change mitigation. To complement the Sustainable Development Goals of the Post-2015 Development Agenda, the Outlook sets forth Global Waste Management Goals and a Global Call to Action to achieve those goals
DinamiÄka simulacija mehaniÄkih optereÄenja â pristup zasnovan na svojstvima industrijskih elektromotornih pogona
Dynamic emulation of mechanical loads presents a modern and interesting approach for testing and validating performance of electrical drives without a real mechanical load included in the test rig. The paper presents an approach to dynamic emulation of mechanical loads when the load torque and inertia mass of emulated load can be significantly greater than that of laboratory test rig. Closed-loop control of load torque and feedforward compensation of inertia and friction torques are used in a test rig. The approach is focused on the use with standard industrial converters. The described method can be used for design and validation of speed control algorithms in mechatronic applications. Experimental results with the emulation of linear loads are presented in end of the paper.DinamiÄka simulacija mehaniÄkih optereÄenja predstavlja moderan i zanimljiv pristup testiranju i validaciji ponaĆĄanja elektromotornih pogona bez ukljuÄenog stvarnog mehaniÄkog optereÄenja u eksperimentalni postav. U radu je predstavljen pristup s dinamiÄkom simulacijom mehaniÄkih optereÄenja za sluÄaj kada moment tereta ili moment tromosti simuliranog tereta mogu biti daleko veÄi od onih dostupnih u eksperimentalnom postavu. U postavu se koristi upravljanje momentom tereta u zatvorenoj petlji uz unaprijednu petlju kompenzacije momenta tromosti i momenata trenja. Pristup je usmjeren na upotrebu standardnih industrijskih pretvaraÄa. Opisana metoda moĆŸe se koristiti za sintezu i validaciju algoritama za upravljanje po brzini u mehatroniÄkim primjenama. U radu su predstavljeni eksperimentalni rezultati za sluÄaj simulacije linearnih tereta
GAME: Grb and All-sky Monitor Experiment
We describe the GRB and All-sky Monitor Experiment (GAME) mission submitted
by a large international collaboration (Italy, Germany, Czech Repubblic,
Slovenia, Brazil) in response to the 2012 ESA call for a small mission
opportunity for a launch in 2017 and presently under further investigation for
subsequent opportunities. The general scientific objective is to perform
measurements of key importance for GRB science and to provide the wide
astrophysical community of an advanced X-ray all-sky monitoring system. The
proposed payload was based on silicon drift detectors (~1-50 keV), CdZnTe (CZT)
detectors (~15-200 keV) and crystal scintillators in phoswich (NaI/CsI)
configuration (~20 keV-20 MeV), three well established technologies, for a
total weight of ~250 kg and a required power of ~240 W. Such instrumentation
allows a unique, unprecedented and very powerful combination of large field of
view (3-4 sr), a broad energy energy band extending from ~1 keV up to ~20 MeV,
an energy resolution as good as ~300 eV in the 1-30 keV energy range, a source
location accuracy of ~1 arcmin. The mission profile included a launch (e.g., by
Vega) into a low Earth orbit, a baseline sky scanning mode plus pointed
observations of regions of particular interest, data transmission to ground via
X-band (4.8 Gb/orbit, Alcantara and Malindi ground stations), and prompt
transmission of GRB / transient triggers.Comment: 13 pages, 8 figures, published in International Journal of Modern
Physics
Evidence for a unitary structure of spatial cognition beyond general intelligence
Performance in everyday spatial orientation tasks (e.g. map reading and navigation) has been considered functionally separate from performance on more abstract object-based spatial abilities (e.g. mental rotation and visualization). However, evidence remains scarce and unsystematic. With a novel gamified battery, we assessed six tests of spatial orientation in a virtual environment and examined their association with ten object-based spatial tests, as well as their links to general cognitive ability (g). We further estimated the role of genetic and environmental factors in underlying variation and covariation in these spatial tests. Participants (N = 2,660) were part of the Twins Early Development Study, aged 19 to 22. The 6 tests of spatial orientation clustered into a single âNavigationâ factor that was 64% heritable. Examining the structure of spatial ability across all 16 tests, three factors emerged: Navigation, Object Manipulation and Visualization. These, in turn, loaded strongly onto a general factor of Spatial Ability, which was highly heritable (84%). A large portion (45%) of this high heritability was independent of g. The results from this most comprehensive investigation of spatial abilities to date point towards the existence of a common genetic network that supports all spatial abilities
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