Seasonal variation of vitamin B12, B12 analogs, and phytoplankton in a Long Island estuary

Dissolved vitamin B12 concentrations in the Peconic Bay estuary, Long Island, were determined over a seasonal period by assay with the diatom Thalassiosira pseudonana clone 3H…

children: differentiation using diffusion-weighted magnetic resonance imaging

Purpose To evaluate differences in magnetic resonance imaging (MRI) appearance between infantile hemangiomas and rhabdomyosarcomas of the orbit in pediatric patients using diffusion-weighted imaging. Methods A multicenter retrospective review of MRIs of pediatric patients with infantile hemangiomas and rhabdomyosarcomas of the orbit was performed. MRI examinations from a total of 21 patients with infantile hemangiomas and 12 patients with rhabdomyosarcomas of the orbit were independently reviewed by two subspecialty board-certified neuroradiologists masked to the diagnosis. A freehand region of interest was placed in the mass to obtain the mean apparent diffusion coefficient (ADC) value of the mass as well as within the medulla to obtain a ratio of the ADC mass to the medulla. A t test was used to compare mean ADC and ADC ratios between the two groups. Receiver operating characteristic analysis was performed to determine ADC value and ADC ratio thresholds for differentiation of infantile hemangioma and rhabdomyosarcoma. Results There was a statistically significant difference in the mean ADC value of infantile hemangiomas compared to rhabdomyosarcomas (1527 × 10−6 mm2/s vs 782 × 10−6 mm2/s; P = 0.0001) and the ADC ratio of the lesion to the medulla (1.77 vs 0.92; P = 0.0001). An ADC threshold of <1159 × 10−6 mm2/sec and an ADC ratio of <1.38 differentiated rhabdomyosarcoma from infantile hemangioma (sensitivity 100% and 100%; specificity 100% and 100%) with area under the curve of 1.0 and 1.0, respectively. Conclusions In conjunction with conventional MRI sequences, ADC values obtained from diffusion-weighted MRI are useful to differentiate orbital infantile hemangiomas from rhabdomyosarcomas in pediatric patients

Magnetic resonance imaging findings in children with spasmus nutans

Background Spasmus nutans (SN) is a rare pediatric ophthalmologic syndrome characterized by nystagmus, head bobbing, and abnormal head positioning. Historically, SN has been associated with underlying optic pathway gliomas (OPG); however, evidence of this association is based primarily on a small number of isolated case reports. Prior retrospective analyses have found the rate of OPG to be <2%, but these studies only intermittently used neuroimaging with computed tomography, which has limited sensitivity for detection of small lesions in the optic pathway. The purpose of this study was to investigate the association of SN with intracranial abnormalities, particularly OPG, using magnetic resonance imaging of the brain and orbits. Methods Neuroradiology databases at three institutions spanning January 2010 to May 2016 were queried for examinations ordered for evaluation of SN; MRI examinations of the brain and/or orbits were included and evaluated for OPG and other structural abnormalities. Medical records were reviewed to confirm a diagnosis of SN, presence of other underlying neurological disease, or preexisting diagnoses. Results A total of 40 patients with eligible MRI examinations were identified. None had optic nerve pathway gliomas. Two children had optic nerve hypoplasia; no other patients had optic pathway abnormalities. None had intracranial or orbital masses. MRI examinations were normal in 25 patients. Conclusions This series represents the largest collection of MRI examinations for SN in the literature to date and shows no association between OPG and SN. In children presenting with SN but no other findings suggesting OPG or neurological abnormalities, neuroimaging may not be required

Novel geopolymer for use as a sensible storage option in high temperature thermal energy storage systems

In the current study a novel geopolymer created from waste materials (namely fly ash and black slag) has been characterised as a potential high temperature thermal energy storage material option. Several geopolymer samples have been fabricated and characterised by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Additionally, the density and heat capacity have been determined. Lastly, the cost of the material and packed bed system was estimated showing that the geopolymer-based systems are potentially 35% cheaper than the traditional 2-tank molten salt systems.This research was performed as part of the Australian Solar Thermal Research Institute (ASTRI), a project supported by the Australian Government, through the Australian Renewable Energy Agency (ARENA). The work was partially funded by the Spanish government (ENE2015-64117-C5-1-R (MINECO/FEDER)). The authors would like to thank the Catalan Government for the quality accreditation given to their research group (2014 SGR 123). GREA is certified agent TECNIO in the category of technology developers from the Government of Catalonia. This project has received funding from the European Commission Seventh Framework Programme (FP/2007-2013) under Grant agreement Nº PIRSES-GA-2013-610692 (INNOSTORAGE) and from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 657466 (INPATH-TES). Aran Solé would like to thank Ministerio de Economía y Competitividad de España for Grant Juan de la Cierva, FJCI-2015-25741. The authors would also like to acknowldege the Diopma group from the University of Barcelona thanks the funding by the Spanish Government (RTI2018-093849-B-C32), and the Catalan Government for the quality accreditation (2017 SGR 118)

Novel Geopolymer for Use as a Sensible Storage Option in High Temperature Thermal Energy Storage Systems

In the current study a novel geopolymer created from waste materials (namely fly ash and black slag) has been characterised as a potential high temperature thermal energy storage material option. Several geopolymer samples have been fabricated and characterised by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Additionally, the density and heat capacity have been determined. Lastly, the cost of the material and packed bed system was estimated showing that the geopolymer-based systems are potentially 35% cheaper than the traditional 2-tank molten salt systems

Tracking Structural Deactivation of H-Ferrierite Zeolite Catalyst During MTH with XRD

publishedVersio

Extracellular Matrix Degradation Products and Low-Oxygen Conditions Enhance the Regenerative Potential of Perivascular Stem Cells

Tissue and organ injury results in alterations of the local microenvironment, including the reduction in oxygen concentration and degradation of the extracellular matrix (ECM). The response of perivascular stem cells to these microenvironment changes are of particular interest because of their wide distribution throughout the body and their potential involvement in tissue and organ response to injury. The chemotactic, mitogenic, and phenotypic responses of this stem cell population were evaluated in response to a combination of decreased oxygen concentration and the presence of ECM degradation products. Culture in low-oxygen conditions resulted in increased proliferation and migration of the cells and increased activation of the ERK signaling pathway and associated integrins without a change in cell surface marker phenotype. The addition of ECM degradation products were additive to these processes. Reactive oxygen species within the cells were increased in association with the mitogenic and chemotactic responses. The increased proliferation and chemotactic properties of this stem cell population without any changes in phenotype and differentiation potential has important implications for both in vitro cell expansion and for in vivo behavior of these cells at the site of injury

Impacts of aspergillosis on sea fan coral demography: modeling a moving target

Little is known about how epizootics in natural populations affect vital rates and population structure, or about the process of recovery after an outbreak subsides. We investigated the effects of aspergillosis, an infectious disease caused by the fungal pathogen Aspergillus sydowii, on the demography of a gorgonian coral, Gorgonia ventalina. Caribbean sea fans were affected by a seven-year epizootic, marked by an initial period in 1994 of high infection prevalence, high mortality rates, and almost complete reproductive failure of infected fans. Post epizootic, in 2005, host populations were relatively healthy, with low disease prevalence. Using longitudinal data from populations on coral reefs in the Florida Keys (USA) and the Yucatán Peninsula (Mexico), we documented changes in the epidemiology of sea fan aspergillosis over the course of the epizootic. We developed an "integral projection model" that scales disease impacts from individual to population levels using direct estimates of vital rates. Within-colony lesion growth rate and host mortality were higher during the peak of the epizootic. Effects on individuals and populations changed substantially post-epizootic; recruitment increased, mortality of infected adults decreased, and the size dependence of infection was reduced. Elasticity analysis indicated that population growth is more sensitive to changes in the growth and survival of established colonies than to recruitment, due to slow colony growth and the longevity and fecundity of large adults. Disease prevalence in our monitored populations decreased from ∼50% in 1997 to <10% by 2003 and <1% in 2007 and was accompanied by very high mortality during the early stages of the epizootic. The population model suggested that host evolution (due to selection for higher disease resistance through differential mortality) could proceed quickly enough to explain the observed changes in prevalence and in the size independence of infection risk. Our model indicates that the time required for population recovery following an outbreak is largely determined by the percentage of healthy tissue lost from the population. However, recovery following an especially severe outbreak (i.e., 80% or more tissue loss) is much faster if the affected population receives an external supply of recruits from unaffected areas

Imaging and Demography of the Host Galaxies of High-Redshift Type Ia Supernovae

We present the results of a study of the host galaxies of high redshift Type Ia supernovae (SNe Ia). We provide a catalog of 18 hosts of SNe Ia observed with the Hubble Space Telescope (HST) by the High-z Supernova Search Team (HZT), including images, scale-lengths, measurements of integrated (Hubble equivalent) BVRIZ photometry in bands where the galaxies are brighter than m ~ 25 mag, and galactocentric distances of the supernovae. We compare the residuals of SN Ia distance measurements from cosmological fits to measurable properties of the supernova host galaxies that might be expected to correlate with variable properties of the progenitor population, such as host galaxy color and position of the supernova. We find mostly null results; the current data are generally consistent with no correlations of the distance residuals with host galaxy properties in the redshift range 0.42 < z < 1.06. Although a subsample of SN hosts shows a formally significant (3-sigma) correlation between apparent V-R host color and distance residuals, the correlation is not consistent with the null results from other host colors probed by our largest samples. There is also evidence for the same correlations between SN Ia properties and host type at low redshift and high redshift. These similarities support the current practice of extrapolating properties of the nearby population to high redshifts pending more robust detections of any correlations between distance residuals from cosmological fits and host properties.Comment: 35 pages, 12 figures, 4 tables, accepted for publication in A

Zooming in and out : studying practices by switching theoretical lenses and trailing connections

This paper contributes to re-specifying a number of the phenomena of interest to organisational studies in terms of patterns of socio-material practices and their effects. It does so by outlining a vocabulary and strategy that make up a framework for theorising work and organisational practices. The vocabulary is based on number of sensitising concepts that connote practice as an open-ended, heterogeneous accomplishment which takes place within a specific horizon of sense and a set of concerns which the practice itself brings to bear. The strategy is based on the metaphorical movement of "zooming in" and "zooming out of" practice. The zooming in and out are obtained through switching theoretical lenses and repositioning in the field, so that certain aspects of the practice are fore-grounded while others are bracketed. Building on the results of an extended study of telemedicine, the paper discusses in detail the different elements of the framework and how it enhances our capacity to re-present practice. The paper concludes with some considerations on how the proposed approach can assist us in advancing the research agenda of organizational and work studies