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To quantitatively test the hypothesis that older patients have increased thyroarytenoid muscle atrophy by comparing thyroarytenoid muscle volumes across different age groups.
A retrospective chart review was conducted. The study included 111 patients with no history of laryngeal pathology. Two investigators reviewed magnetic resonance imaging studies of these patients and manually traced the thyroarytenoid muscles on multiple slices bilaterally. Thyroarytenoid muscle volumes were then computed using imaging analysis software. Patients were stratified into three age groups (18–50 years, 51–64 years, and 65 years or older) for comparison.
Intra- and inter-rater reliabilities were excellent for all measurements (intraclass correlation co-efficient > 0.90). There was no statistically significant difference in the mean volumes of left and right thyroarytenoid muscles in all age and gender groups.
Given the lack of statistically significant difference in thyroarytenoid muscle volume between age groups on magnetic resonance imaging, the prevailing assumption that age-related thyroarytenoid muscle atrophy contributes to presbyphonia should be re-examined.
The hedging practices survey took place towards the end of 2015 in the final few months prior to Solvency II regulations coming into force. At the point of completing the survey we would expect that companies would have largely transitioned their hedging approaches to work in a Solvency II environment. There may be some cases where further changes were planned but not implemented at the point of completing the survey. Further, as familiarity with working under the new regulations increases, approaches are expected to continue to develop over time. The working party hopes that this report is useful in summarising industry attitudes at this point in time and as a comparator in future years. Before launching the survey we did have several conjectures of what we may expect to see in the results. Some proved true, for some it was difficult to glean any strong conclusion from the data, and there were one or two where results countered what we expected to see.
TOOLS, TECHNIQUES, MODELS AND ANALYSES TO RESOLVE COMPLEX WATER PROBLEMS
Udit Bhatia, Sustainability & Data Sciences Laboratory, Civil & Environmental Engineering, Northeastern University, Boston, Massachusetts, USA,
Devashish Kumar, Sustainability & Data Sciences Laboratory, Civil & Environmental Engineering, Northeastern University, Boston, Massachusetts, USA,
Evan Kodra, Sustainability & Data Sciences Laboratory, Civil & Environmental Engineering, Northeastern University, Boston, Massachusetts, USA,
Auroop R. Ganguly, Sustainability & Data Sciences Laboratory, Civil & Environmental Engineering, Northeastern University, Boston, Massachusetts, USA
Climate projections, especially at decadal to century scales, rely on physics- based computer models. While the models have generated useful information about global warming and hydrology, “the sad truth of climate science is that the most crucial information is the least credible” (Schiermeier 2010). The possible reasons include intrinsic variability of the climate system as well as our lack of understanding of the physics and the inability to include known physics within the current generation of computer models. Data sciences, ranging from statistics and signal processing to machine learning and nonlinear dynamics, continue to help fill some of the crucial gaps in climate. We hypothesize that these data science solutions can be improved if they are driven by physical knowledge, especially when this knowledge cannot be incorporated in current climate models because they are incomplete or incompatible. We have called this paradigm Physics-Guided Data Mining (PGDM) (Ganguly et al. 2014). In addition to motivating and introducing PGDM, this chapter presents three case studies on precipitation, based on our prior work. Statistical downscaling, which generates higher- resolution projections from lower- resolution model simulations, benefits from a blend of sparse learning techniques with physically motivated covariates (Das et al. 2014; 2015). Multimodal uncertainty quantification shows the potential to improve when physical relations with ancillary variables are considered together with historical skills and future consensus, within a Bayesian framework (Ganguly et al. 2013; Kodra 2014a; Smith et al. 2009). Characterization of internal variability and associated model performance benefit from data- driven analysis of multi- initial condition ensembles, combined with physical understanding of oceanic indices and their initializations (Kodra et al. 2012). The proposed PGDM paradigm, illustrated through our prior publications, shows the potential to bridge crucial knowledge gaps in climate science and help in translation to water resources impacts.
The Grand Water Challenge
Our planet and society continue to be critically shaped by water. In the 21st century and beyond, water is without question among the major clear and present challenges facing the world (Hall et al. 2014). Water in the atmospheric column is perhaps the most important of all the greenhouse gases and causes the most significant uncertainties in our understanding and projections of climate variability and change. Water in the oceans is critical for the survival of the majority of species while water towers in glaciers sustain riverine systems.
The aim of the present work is two-fold: 1) To study the effect of the tidal field of the Galactic bulge on a cluster in a high eccentricity plunging orbit with half-mass density nearly equal to the Roche density; 2) To estimate the tidal or limiting radius for such orbits.
The possible existence of binary clusters in our Galaxy (h and x Persei, Ocl 556) has been argued in the past, but it has never been a well established fact either in our Galaxy, or in external systems. An early speculation on the problem by Innanen et al (1972) has predicted a considerable degree of stability for binary clusters in low nuclear density galaxies, like the LMC.
A field experiment was carried out at the farm of Indian Agricultural Research Institute, New Delhi to quantify the effect of elevated carbon dioxide (CO2) and different levels of N fertiliser application on nitrous oxide (N2O) and carbon dioxide (CO2) emissions from soil under maize. The experiment included five treatments: 60 kg N ha−1 under ambient CO2 (385 ppm) in open plots, 120 kg N ha−1 under ambient CO2 (385 ppm) in open plots, 160 kg N ha−1 under ambient CO2 (385 ppm) in open plots, 120 kg N ha−1 under ambient CO2 (385 ppm) in open top chambers (OTC) and 120 kg N ha−1 under elevated CO2 (500 ± 50 ppm) in the OTC. Peaks of N2O flux were observed after every dose of N application. Cumulative N2O emission was 13% lower under ambient CO2 as compared to the elevated CO2 concentrations. There was an increase in CO2 emissions with application of N from 60 kg ha−1 to 160 kg ha−1. Higher yield and root biomass was observed under higher N treatment (160 kg N ha−1). There was no significant increase in maize yield under elevated CO2 as compared to ambient CO2. The carbon emitted was more than the carbon fixed under elevated CO2 as compared to ambient CO2 levels. The carbon efficiency ratio (C fixed/C emitted) was highest in ambient CO2 treatment in the OTC.
The findings of the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) study and the Cost Utility of the Latest Antipsychotic Drugs in Schizophrenia Study (CUtLASS) called previous trials of antipsychotics into question, including pre-licensing trials. Concerns regarding methodological robustness and quality of reporting increased. This systematic review aimed to examine the quality of reporting of phase II and III trials for new antipsychotics in the aftermath of the CATIE and CUtLASS studies.
Electronic searches were conducted in EMBASE, Medline and Cochrane databases and also ClinicalTrials.gov for antipsychotic trials (published between January 2006 and February 2012). Phase II and III randomized controlled trials (RCTs) for iloperidone, asenapine, paliperidone, olanzapine, lurasidone and pomaglumetad methionil were selected for schizophrenia and schizoaffective disorder. The reporting of the methodology was evaluated in accordance with Consolidated Standards of Reporting Trials (CONSORT) guidelines.
Thirty-one articles regarding 32 studies were included. There was insufficient reporting of design in 47% of studies and only 13% explicitly stated a primary hypothesis. Exclusion criteria were poorly reported for diagnosis in 22% of studies. Detail regarding comparators, particularly placebos, was suboptimal for 56% of studies, and permitted concomitant medication was often not reported (19%). Randomization methods were poorly described in 56% of studies and reporting on blinding was insufficient in 84% of studies. Sample size calculations were insufficiently reported in 59% of studies.
The quality of reporting of phase II and III trials for new antipsychotics does not reach the standards outlined in the CONSORT guidelines. Authors often fail to adequately report design and methodological processes, potentially impeding the progress of research on antipsychotic efficacy. Both policymakers and clinicians require high quality reporting before decisions are made regarding licensing and prescribing of new antipsychotics.
We have developed a novel electrochemical system for field assisted, fluidic assembly of objects on a microfabricated silicon substrate by means of electrical addressing. The principle of our technique is based on the movement of charged species in solution to oppositely charged electrodes, as seen commonly in electrophoresis. Here, charged species such as beads and cells are moved electrokinetically through an aqueous solution towards a charged electrode. Micro patterning of the electrodes allows localization of charged species. We present a theoretical framework to predict the electric potential for assembly and disassembly of spherical objects. We correlate theoretical predictions with the motion of negatively charged polystyrene beads of 20 μm diameter on 100 μm feature micro patterned substrates. In addition, we extended these results to arraying of 20-30 μm diameter live mammalian cells by means of electrical addressing. This technique has applications in creation of ‘active’ cellular arrays for cell biology research, drug discovery and tissue engineering.
Rheology and dynamic light scattering capture re-entrant behavior of laponite-polymer systems. Neat laponite under basics conditions and concentrations of 2wt% or greater forms a viscoelastic soft glass due to electrostatic repulsions. We show that that addition of low molecular weight poly(ethylene oxide) (PEO) melts the glass due to a depletion force. The depletion force speeds up dynamics in the system resulting in a low viscosity solution. A re-entrant viscoelastic solid is formed with the addition of high molecular weight PEO due to the polymer chains bridging between laponite particles. As expected the transition from a low to high viscosity solution scales with the polymer mean square end-to-end distance and gap between laponite particles.
We have performed for the first time a complete structural characterization of PLA-PEO-PLA in the solution and hydrogel states. Previous studies on hydrogels of these polymers have shown that these gels have excellent mechanical properties suitable for possible application in tissue engineering and drug delivery. We have performed SANS, USAXS and confocal microscopy to relate the change in micro to nano scale self-assembled structure of these polymers in aqueous solution with changes in the block length and stereospecificity of the PLA block. A significant difference in structure and association behavior was seen between the polymers made from amorphous D/L-lactide as compared to those with crystalline L lactide blocks. In the former case spherical micelles were seen to form whereas the latter forms nonspherical polydisperse micellar assemblies. Both polymers form an associative network structure at higher concentrations, leading to gelation. USAXS and confocal microscopy show the presence of large-scale fractal aggregates in the hydrogels of these polymers. The fractal structure was denser for the L lactide series polymers as compared to the D/L-lactide series polymers. These results show that we can tune the microstructure and thereby the mechanical strength of these gels depending upon the specific application we need it for. We also show profiles for release of hydrophobic drug sulindac from 5 weight% solutions of these polymers in phosphate buffer saline. The profiles follows an almost zero order release behavior that continues slowly and steadily over several days and is again found to be strongly dependent on the crystallinity and molecular weight of the PLA block.
Nanoindentation and nanoscratching experiments have been performed to assess the mechanical and tribological behavior of three thin film materials with potential application as wear resistant coatings for magnetic disk storage: (1) hydrogenated-carbon (CHx); (2) nitrogenated-carbon (CNx); and (3) boron suboxide (BOx). The hardness and elastic modulus were measured using nanoindentation. Ultra-low load nanoscratching tests were performed to assess the relative scratch resistance of the films and measure their friction coefficients. The mechanical and tribological performance of the three materials are discussed and compared.
Nanoindentation and nanoscratching experiments have been performed to assess the mechanical properties of several carbon thin films with potential application as wear resistant coatings for magnetic disks. These include three hydrogenated-carbon films prepared by sputter deposition in a H2/Ar gas mixture (hydrogen contents of 20, 34, and 40 atomic %) and a pure carbon film prepared by cathodic-arc plasma techniques. Each film was deposited on a silicon substrate to thickness of about 300 nm. The hardness and elastic modulus were measured using nanoindentation methods, and ultra-low load scratch tests were used to assess the scratch resistance of the films and measure friction coefficients. The results show that the hardness, elastic modulus, and scratch resistance of the 20% and 34% hydrogenated films are significantly greater than the 40% film, thereby showing that there is a limit to the amount of hydrogen producing beneficial effects. The cathodic-arc film, with a hardness of greater than 59 GPa, is considerably harder than any of the hydrogenated films and has a superior scratch resistance.
Need for efficient blue light emitting source for optoelectronic device applications such as flat panel displays has made the research in luminescent material ever so important. Tungsten doped zinc oxide (ZnO:W) has been identified as a blue light emitting phosphor exhibiting cathodoluminescence near 490 nm. This paper details work done on ZnO:W phosphor preparation conditions for efficient light emission from the phosphor. Material characterization to identify the possible source of blue light emission will also be discussed.
Tribochemical studies of the effect of lubricant bonding on the tribology of the head/disk interface (HDI) were conducted using hydrogenated (CHx) carbon disk samples coated with perfluoropolyether ZDOL lubricant. The studies involved drag tests with uncoated and carboncoated Al2O3-TiC sliders and also thermal desorption experiments in an ultra-high vacuum (UHV) tribochamber. We observed that a larger mobile lubricant portion significantly enhances the wear durability of the (head/disk interface) HDI by providing a reservoir to constantly replenish the lubricant displaced in the wear track during drag tests. In the thermal desorption tests we observed two distinct temperatures of desorption. The mobile ZDOL layer is desorbed at the lower thermal desorption temperature and the residual bonded ZDOL layer is desorbed at the higher thermal desorption temperature. We also observed that the hydrogen evolution from CHx overcoats initiates lubricant catalytic decomposition with uncoated Al2O3/TiC sliders, forming CF3 (69) and C2F5 (119). The generation of Hydroflouric acid (HF) during thermal desorption experiments provides the formation mechanism of Lewis acid, which is the necessary component for catalytic reaction causing Z-DOL lube degradation.
Polychromatic X-ray microdiffraction (PXM) is sensitive to the density and organization of the dislocations, which occurs at several structural levels. At the lowest level statistically stored (dipolar) individual dislocations can exist within a crystal. At a higher structural level dislocations can organize into strongly correlated arrangements including walls and sub-boundaries. After plastic deformation geometrically necessary (polar) dislocations as well as geometrically necessary boundaries may be formed in a crystal. These dislocations cause not only random deformation, but also strongly correlated long range rotations within the crystal, grain, or subgrain. Non homogeneous plastic deformation is observed even in single crystals at smaller scale. Polar dislocations spread the conditions for x-ray (or neutron) diffraction transverse to the reciprocal space vector of each reflection. Diffracted intensity depends on the second rank dislocation density tensor. The polar dislocations density is related to the incompatibility of the plastic deformation and to the local lattice curvature. Laue patterns are therefore sensitive to the ratio between polar and dipolar dislocations density. Different slip systems of polar dislocations population cause distinctly different streaking in Laue patterns. Examination of streaked patterns enables one to determine statistically stored (dipolar) dislocations and geometrically necessary (polar) dislocations, GNDs, and to quantitativly determine the dislocation patterning parameters. The co-evolution of the statistically stored (dipolar) and geometrically necessary dislocations (polar) may be analyzed, and the ratio between the two densities may be obtained from the analysis of the Laue spots intensity distribution. The microbeam technique is applied to analyze a dislocation structure in a Ni bicrystal under uniaxial pulling.
The deformation behavior of BCC metals is being investigated by x-ray microdiffraction measurements (μXRD) for the purpose of characterizing the dislocation structure that results from uniaxial compression experiments. The high brilliance synchrotron source at the Advanced Light Source (Lawrence Berkeley National Lab) and the micron resolution of the focusing optics allow for the mapping of Laue diffraction patterns across a sample. These measurements are then analyzed in order to map the distribution of residual stresses in the crystal. An important finding is the observation of Laue spot “streaking”, which indicates localized rotations in the lattice. These may represent an accumulation of same-sign dislocations. Theoretical modeling of the diffraction response for various slip systems is presented, and compared to experimental data. Preliminary results include orientation maps from a highly strained Ta bicrystal and a less highly strained Mo single crystal. The orientation maps of the bicrystal indicate a cell-like structure of dense dislocation walls. This deformation structure is consistent with previous OIM studies of the same crystal. The results suggest that μXRD may be a particularly useful tool for microscale studies of deformation patterns in a multi-scale investigation of the mechanisms of deformation that ranges from macroscopic deformation tests to high resolution TEM studies of dislocation structures.