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Analysis of variance and uncertainty analysis are analogous techniques for partitioning variability. In both analyses negative interaction terms due to negative covariance terms that appear when non-orthogonal predictor variables are allowed may occur. Uncertainties can be estimated directly from variances if the form of distribution is assumed. The decision as to which of the techniques to use depends partly on the properties of the criterion variable. Only uncertainty analysis may be used with a non-metric criterion. Since uncertainties are dimensionless (using no metric), however, uncertainty analysis has a generality which may make it useful even when variances can be computed.
To investigate the symptoms of SARS-CoV-2 infection, their dynamics and their discriminatory power for the disease using longitudinally, prospectively collected information reported at the time of their occurrence. We have analysed data from a large phase 3 clinical UK COVID-19 vaccine trial. The alpha variant was the predominant strain. Participants were assessed for SARS-CoV-2 infection via nasal/throat PCR at recruitment, vaccination appointments, and when symptomatic. Statistical techniques were implemented to infer estimates representative of the UK population, accounting for multiple symptomatic episodes associated with one individual. An optimal diagnostic model for SARS-CoV-2 infection was derived. The 4-month prevalence of SARS-CoV-2 was 2.1%; increasing to 19.4% (16.0%–22.7%) in participants reporting loss of appetite and 31.9% (27.1%–36.8%) in those with anosmia/ageusia. The model identified anosmia and/or ageusia, fever, congestion, and cough to be significantly associated with SARS-CoV-2 infection. Symptoms’ dynamics were vastly different in the two groups; after a slow start peaking later and lasting longer in PCR+ participants, whilst exhibiting a consistent decline in PCR- participants, with, on average, fewer than 3 days of symptoms reported. Anosmia/ageusia peaked late in confirmed SARS-CoV-2 infection (day 12), indicating a low discrimination power for early disease diagnosis.
Paediatric studies have shown serum N-terminal pro b-type natriuretic peptide levels to be a valuable tool in the surveillance of myocardial function and an early biomarker for rejection in transplant patients. The correlation between low mean right atrial pressure and increased inferior vena cava collapsibility index is well studied in adults. Our study aims to assess correlation between non-invasive measurements (serum N-terminal pro b-type natriuretic peptide, inferior vena cava dimensions collapsibility, tricuspid regurgitation, and left ventricular remodelling index to invasive mean right atrial pressure in paediatric heart transplant patients).
Methods:
A single centre, retrospective chart review of the paediatric transplant patients from 0 to 21 years of age was performed between 2015 and 2017. Thirty-nine patients had complete data which includes cardiac catheterisation, transthoracic echocardiogram, and serum N-terminal pro b-type natriuretic peptide levels done within a two weeks of interval.
Results:
A higher inferior vena cava collapsibility index correlated with a lower mean right atrial pressure (r = −0.21, p = 0.04) and a larger inferior vena cava diameter in expiration indexed to body surface area (IVCmax/BSA0.5) correlated with a higher mean right atrial pressure (r = 0.29, p = 0.01). There was a correlation between elevated N-terminal pro b-type natriuretic peptide and inferior vena cava collapsibility index (r = −0.38, p = 0.0001), IVCmax/BSA0.5 (r = 0.25, p = 0.0002), and mean right atrial pressure (r = 0.6, p = 0.0001).
Conclusion:
Serum N-terminal pro b-type natriuretic peptide levels correlated to non-invasive measurements (inferior vena cava collapsibility index and IVCmax/BSA0.5) and to the invasive mean right atrial pressure. Non-invasive (IVC-CI IVCmax/BSA0.5) correlates with elevated mean right atrial pressure in this population. Together, these may serve as a reliable surveillance tool in assessing right heart filling pressures and cardiac function within the paediatric heart transplant patient.
Clay minerals are the principal reactive, non-combustible, phases present in the pulverized coal burned in power station furnace units. Despite the short heating time involved, the clay mineral impurity is wholly transformed in the ignition.
Illitic clays are partially melted, fluxed by water and potash, to produce an alumino-silicate melt phase. The melt is frothed by the synchronous production of carbon dioxide in an iron oxide catalysed oxidation of associated carbonaceous matter. This produces the hollow, gasfilled, glass-walled spheres (cenospheres) characteristic of pulverized fuel ash (PFA). Partial, primary devitrification crystallization of mullite and quartz from the high-alumina glass is general and the extent of devitrification may influence the pozzolanic efficiency of the PFA cenospheres.
Without the advantage of potash fluxing, the kaolinite lattices are dehydrated and transformed, without melting, to amorphous aluminosilicate and crystalline mullite.
Oxidation of pyrite leads to coating of cenospheres by condensed magnetite and the emission of sulphur dioxide in the flue gases.
The objective of the study was to assess the post-weaning growth response of Sahiwal calves reared on four different pre-weaning dietary regimens. The four diets were: (a) whole cow's milk, starter ration (SR; CP = 20%, total digestible nutrients (TDN) = 72%) and Berseem hay (H; Egyptian clover; CP = 21%, TDN = 63%); (b) whole cow's milk + H; (c) milk replacer (MR; reconstituted to supplier specification; Sprayfo®) + SR + H; and (d) MR + H. The protein and fat percentages of reconstituted MR were 2.22 and 1.84, respectively. Milk or MR were fed at the rate of 10% of the calves’ body weight (BW) until 56 days of age, and then withdrawn gradually until weaned completely by 84 days of age. The average initial BW of calves in groups A, B, C and D were 56.3 ± 1.0, 47.5 ± 1.0, 40.4 ± 1.0 and 30.3 ± 1.0 kg, respectively. Initially, there were 12 calves in each group with six of each sex; however, one male calf died from each of groups B and C and were not replaced. During the post-weaning period, 13 to 24 weeks, the calves were fed a single total mixed ration ad libitum based on maize, canola meal, wheat straw and molasses containing 16% CP and 70% TDN. Daily feed intake and weekly BW gains were recorded. The data were analyzed by MIXED model analysis procedures using the statistical program SAS. The intake of calves as percent of their BW, feed conversion ratio and cost per kg of BW gain were not different (P > 0.05) across treatments. The daily gain at 24 weeks of age for the pre-weaning treatments A, B, C and D were 746 ± 33, 660 ± 33, 654 ± 33 and 527 ± 33 g/day and the final liveweights of calves were 119 ± 4.2, 102 ± 4.2, 95 ± 4.2 and 75 ± 4.2 kg, respectively. Gains were influenced significantly (P < 0.05) by pre-weaning treatments. The calves fed MR and H only during the pre-weaning period were unable to catch up post weaning with calves on other dietary treatments. The calves fed whole milk from birth at the rate of 10% of liveweight together with concentrates had higher weaning weight and superior growth rate post weaning as well. Thus, pre-weaning feeding was important for higher weaning weights and superior growth rates post weaning.
A zeroth order dendritic carbosilane structure, SiFA4H with four hexafluoroisopropanol (HFIP) functional groups attached via propyl ligand arms to a central silicon atom, has been developed as a model hydrogen-bond (HB) acid sorbent coating and candidate reference HB acid. The HB donor interaction, through the hydroxyl of the HFIP moiety, with a solute HB base can be monitored by observing the hydroxyl stretching frequency through measurements of SiFA4H FTIR spectra before and during vapor exposure. HFIP hydroxyl stretch shifts, upwards of 700 cm-1 have been observed depending on the HB base. For a range of HB bases, the resulting hydroxyl stretch shifts correlate directly with the solute HB basicity scale, “B”, developed by Abraham et al [1]. A variety of techniques exist to measure solute HB basicity, however, the applicability to examine HB bases delivered as vapors or gases and the simplicity of the measurements described herein, with a reusable reference HB acid sorbent coating and standard FTIR spectrophotometer techniques is attractive for some applications including those with hazardous chemicals. Moreover, as an extension of this work we propose employing SiFA4H or related sorbents as molecular sensing coatings, where the semi-selective sorbent is examined by various infrared (IR) spectroscopic techniques to monitor and identify hazardous chemicals, taking advantage of molecular binding phenomena which occur in the sorbent [2].
RED is a technique we have developed for stand-off detection of trace explosives using infrared (IR) photo-thermal imaging [1,2,3]. RED incorporates compact IR quantum cascade lasers tuned to strong characteristic absorption bands and may be used to illuminate explosives present as particles on a surface. An IR focal plane array is used to image the surface and detect any small increase in the thermal emission upon laser illumination. We have previously demonstrated the technique at several meters to 10’s of meters of stand-off distance indoors and in field tests [4,5], while operating the lasers below the eye-safe intensity limit (100 mWcm2) [6]. Sensitivity to traces of explosives as small as a nanogram has been demonstrated. By varying the incident wavelength slightly, we can readily show selectivity between individual explosives such as TNT and RDX. Using a sequence of lasers at different wavelengths, we increase both sensitivity and selectivity. A complete detection protocol can be performed in a sub-second time domain. More recently, RED has been used to emphasize measurements with cooled detectors in addition to examining the utility of filtering the collected thermal emission signal which is rich in analyte-specific spectroscopic information. A next generation RED system and detection algorithm is being developed to take advantage of these more powerful features. This manuscript will include an overview of the approach and recent experimental results.
The low vapor pressure of many energetic materials presents a challenge for detection by non-contact methods. We address this limitation by illuminating energetic materials including TNT and RDX with infrared lasers tuned to strong molecular absorption bands to efficiently heat trace amounts present on substrates. This substantially increases their vapor signatures for direct detection, obviating the need to swab surfaces for solid particles or to collect headspace vapors for extended time periods. The instantaneously generated vapor produced by Laser Trace Vaporization (LTV) can be detected by any number of techniques which can accommodate vapor sampling or spectroscopic analysis. Currently the testbed for LTV incorporates a tunable quantum cascade laser (QCL) to illuminate the sample and an ion mobility spectrometer (IMS) to validate the signal enhancement. The LTV technique works well with all tested substrates, though the thermal and spectroscopic properties of the substrate can influence the efficiency of the vaporization. Computational results from laser heating along with experimental thermal kinetic measurements were used to optimize LTV laser irradiation parameters. In addition to a range of LTV results for different explosives and substrates, we explore the effects of wavelength-dependent heating on the sample and substrate.
We are developing a new non-contact and non-destructive imaging technique which requires no sample preparation and provides similar content information as FTIR or Raman spectroscopy while being immune to fluorescence and offers a potentially faster scan rate and/or higher spatial resolution. It utilizes photo-thermal heating of the sample with a quantum cascade laser (or other suitable infrared laser) and measuring the resulting increase in thermal emissions by either an infrared (IR) detector or a laser probe consisting of a visible laser reflected from the sample. The latter case allows for further increases in the spatial resolution from ∼10 μm to ∼1 μm or better, with suitable experimental conditions. Since the thermal emission signal is proportional to the absorption coefficient, by tuning the wavelength of the IR laser we can directly measure the IR spectrum of the sample. By raster scanning over the surface of the sample we can obtain maps of the chemical composition of the sample surface. We demonstrate this technique by imaging the surface of a micro-fabricated flow-through chemical vapor preconcentrator consisting of a silicon frame and a suspended-perforated polyimide membrane with a pair of platinum heater traces, coated with a custom sorbent polymer for selective sorption of analyte. We measure the spatial resolution of our photo-thermal imaging system as well as discuss the conditions under which the spatial resolution can be further increased from the far-field diffraction limited resolution given by the combination of the imaging optic and IR excitation laser wavelength.
By
Kenneth L. Tanaka, U.S. Geological Survey, Flagstaff,
Robert Anderson, Jet Propulsion Laboratory, California Institute of Technology, Pasadena,
James M. Dohm, Department of Hydrology and Water Resources, University of Arizona, Tucson,
Vicki L. Hansen, Department of Geological Sciences, University of Minnesota Duluth,
George E. McGill, University of Massachusetts, Amherst,
Robert T. Pappalardo, Jet Propulsion Laboratory, California Institute of Technology, Pasadena,
Richard A. Schultz, Geomechanics – Rock Fracture Group, Department of Geological Sciences and Engineering, University of Nevada, Reno,
Thomas R. Watters, Center for Earth and Planetary Studies, National Air and Space Museum, Smithsonian Institution, Washington, DC
As on Earth, other solid-surfaced planetary bodies in the solar system display landforms produced by tectonic activity, such as faults, folds, and fractures. These features are resolved in spacecraft observations directly or with techniques that extract topographic information from a diverse suite of data types, including radar backscatter and altimetry, visible and near-infrared images, and laser altimetry. Each dataset and technique has its strengths and limitations that govern how to optimally utilize and properly interpret the data and what sizes and aspects of features can be recognized. The ability to identify, discriminate, and map tectonic features also depends on the uniqueness of their form, on the morphologic complexity of the terrain in which the structures occur, and on obscuration of the features by erosion and burial processes. Geologic mapping of tectonic structures is valuable for interpretation of the surface strains and of the geologic histories associated with their formation, leading to possible clues about: (1) the types or sources of stress related to their formation, (2) the mechanical properties of the materials in which they formed, and (3) the evolution of the body's surface and interior where timing relationships can be determined. Formal mapping of tectonic structures has been performed and/or is in progress for Earth's Moon, the planets Mars, Mercury, and Venus, and the satellites of Jupiter (Callisto, Ganymede, Europa, and Io).
Venus has a pressure-corrected bulk density that is only 3% less than that of the Earth. In contrast, the surface environments of these two planets are very different. At the mean planetary radius the atmospheric pressure and temperature on Venus are 95 bars and 737 K, respectively. Liquid water cannot exist on the surface, which implies the absence of the processes most effective for erosion and sediment transport on Earth. The planet is completely shrouded in clouds, and temperatures of the lower atmosphere do not vary much from equator to poles, resulting in winds not capable of significant erosion. Most of the materials exposed on the surface of Venus apparently formed during approximately the last 20% of solar system history, with no significant clues to conditions on the planet during prior eons. Because the dense atmosphere has destroyed small bolides, the smallest surviving impact craters have diameters of ~2 km, and the total population of impact craters is less than 1000. The dominant terrain on Venus is plains, which constitute ~80% of the planet's surface. Impact craters are randomly distributed on these plains, and thus differences in the relative age of surface materials based on differences in crater frequency are not statistically robust.
The global topography of Venus does not include the diagnostic plate-boundary signatures that are present on Earth, and thus plate tectonics has not been active on Venus during the time represented by the current surface materials and features.
Effective community treatment of schizophrenia involves not merely the removal of florid symptoms, but restoration of effective social role functioning. The efficacy of a family management approach is compared with an individual approach of similar intensity in terms of its impact on the patient's social adjustment after a florid episode of schizophrenia. Clinical reports, patient self-reports, and interviews with the family members of 36 patients, who were randomly assigned to family or individual management, demonstrated a consistent superiority for family management. The advantages for the family approach were sustained over a two-year period. The potential mechanisms through which the family approach may have achieved its greater efficacy are discussed from a multi-determined perspective.
Thirty-nine strains of (mainly) supra-littoral algae were tested for their ability to utilize glycollic acid for chemotrophic and phototrophic growth at the' natural' pH of 8.c. In no instance was there convincing evidence that glycollate either supported growth in the dark or enhanced the growth rate in the light in the presence of carbon dioxide, although acetate performed one or both these functions in a number of the strains. It was concluded that glycollic acid was unlikely to serve as a significant carbon substrate in neutral or slightly alkaline habitats.
A 3-year field study (1986–88) was conducted in central Alberta to discover how diverse soil-plant systems function under cryoboreal subhumid conditions. Barley, fescue, faba (field) bean and a barley/field pea intercrop were grown continuously on different soils at Ellerslie and Breton using two distinct tillage methods. The agronomic performance, weed-crop interactions and below-ground productivity of these cropping systems were examined. The main findings were as follows: different soil properties did not affect yields of barley, barley/field pea and fescue fertilized with N and P; silage yield of faba bean at Breton was greater than at Ellerslie; barley/field pea and faba bean could be grown without tillage at Ellerslie; barley/field pea plots had the lowest weed counts; fescue root biomass was greatest at all depths followed by faba bean and barley; and soil properties appeared not to induce differences in root production of a cereal, an annual forage legume and a perennial grass. Increasing the use of annual legumes into rotations, either as sole crops or as intercrops with cereals, may be a viable alternative to continuous cereal cropping because annual legumes contribute N through biological N fixation, reduce weed competition and increase the input of root mass in soil.
To provide an up to date review of the literature on aneurysmal bone cysts, including their diagnosis, pathology, pathophysiology, radiology and management.
Method:
Retrospective review of six cases over a 15-year period.
Results:
Six patients (age range, eight months to 17 years; mean, 9.6 years) presented with an aneurysmal bone cyst in the mandible (n = 3), maxilla (n = 2) or occipital soft tissue (n = 1). Each patient underwent primary excision, with one subsequent recurrence.
Conclusion:
Aneurysmal bone cysts are benign but locally destructive entities which may occasionally present to otolaryngologists, since they can involve the head and neck region, in particular the mandible.
The functionalization of polymers and nano-materials with 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) groups provides materials suitable for a variety of preconcentrator and sensor applications. These are especially useful in high vapor pressure, hydrogen-bond basic vapor collection. These specific interactions lead to high efficiency collection of basic analytes such as DMMP (organophosphonates), DNT, and TNT (nitroaromatics). The lower vapor pressure analytes such as RDX have a larger dependence on surface interactions without specific (hydrogen bond) interactions. The use of carbosilane polymers with HFIP pendant groups offers dramatic improvements over fluoropolyol (FPOL) and siloxane polymers in sensor and precon applications. The sorbent capacity and thermal stability are both dramatically improved. In this work we will demonstrate the use of Carbon Nanotube (CNT) composites with HFIP polymers as sorbent coatings and evaluate their use as SPME coatings.