242 research outputs found
Diagnostic test accuracy of remote, multidomain cognitive assessment (telephone and video call) for dementia
A pilot exploratory study examining the potential influence of continuous positive airway pressure devices on cranial molding trajectories in preterm infants
Objective The objective of this exploratory study was to assess the potential impacts of two different continuous positive airway pressure (CPAP) devices on preterm infant head shape and circumference. Study design Twenty infants born at <32 weeks gestational age requiring CPAP support were enrolled. Ten infants used the Hudson RCI Nasal Prong CPAP device and 10 infants used the Fisher- Paykel CPAP device. Infant Cranial Index (CI) and head circumference (HC) were collected weekly as well as infant gestational age at birth, and total number of days on CPAP. Results At baseline, average total birthweight of infants was 1021 grams (SD = 227 grams), average gestational age was 26.9 weeks (SD = 1.80), mean CI was 79.7 cm (SD = 5.95), and HC was 10.2 cm (SD = 0.92). Days on CPAP ranged from 16 to 63 days, with an average of 40.7 (SD = 13.6) days. Neither CI nor HC differed by device type; however, the Fisher-Paykel device was associated with slightly greater HC growth rate. Conclusion CPAP devices and the pressures they apply plausibly contribute to preterm infant cranial molding over time, with the greatest potential impact on infants who require CPAP support for longer periods; however, these findings must be validated in larger cohorts. Additionally, positioning practices should be further examined to determine how they may contribute to or prevent the development of cranial molding deformity
Defining phenotype, tropism, and retinal gene therapy using adeno-associated viral vectors (AAVs) in new-born Brown Norway rats with a spontaneous mutation in Crb1
Mutations in the Crumbs homologue 1 (CRB1) gene cause inherited retinal dystrophies, such as early-onset retinitis pigmentosa and Leber congenital amaurosis. A Brown Norway rat strain was reported with a spontaneous insertion-deletion (indel) mutation in exon 6 of Crb1. It has been reported that these Crb1 mutant rats show vascular abnormalities associated with retinal telangiectasia and possess an early-onset retinal degenerative phenotype with outer limiting membrane breaks and focal loss of retinal lamination at 2 months of age. Here, we further characterized the morphological phenotype of new-born and adult Crb1 mutant rats in comparison with age-matched Brown Norway rats without a mutation in Crb1. A significantly decreased retinal function and visual acuity was observed in Crb1 mutant rats at 1 and 3 months of age, respectively. Moreover, in control rats, the subcellular localization of canonical CRB1 was observed at the subapical region in Muller glial cells while CRB2 was observed at the subapical region in both photoreceptors and Muller glial cells by immuno-electron microscopy. CRB1 localization was lost in the Crb1 mutant rats, whereas CRB2 was still observed. In addition, we determined the tropism of subretinal or intravitreally administered AAV5-, AAV9- or AAV6-variant ShH10(Y445F) vectors in new-born control and Crb1 mutant rat retinas. We showed that subretinal injection of AAV5 and AAV9 at postnatal days 5 (P5) or 8 (P8) predominantly infected the retinal pigment epithelium (RPE) and photoreceptor cells; while intravitreal injection of ShH10(Y445F) at P5 or P8 resulted in efficient infection of mainly Muller glial cells. Using knowledge of the subcellular localization of CRB1 and the ability of ShH10(Y445F) to infect Muller glial cells, canonical hCRB1 and hCRB2 AAV-mediated gene therapy were explored in new-born Crb1 mutant rats. Enhanced retinal function after gene therapy delivery in the Crb1 rat was not observed. No timely rescue of the retinal phenotype was observed using retinal function and visual acuity, suggesting the need for earlier onset of expression of recombinant hCRB proteins in Muller glial cells to rescue the severe retinal phenotype in Crb1 mutant rats.Ophthalmic researc
The G0 Experiment: Apparatus for Parity-Violating Electron Scattering Measurements at Forward and Backward Angles
In the G0 experiment, performed at Jefferson Lab, the parity-violating
elastic scattering of electrons from protons and quasi-elastic scattering from
deuterons is measured in order to determine the neutral weak currents of the
nucleon. Asymmetries as small as 1 part per million in the scattering of a
polarized electron beam are determined using a dedicated apparatus. It consists
of specialized beam-monitoring and control systems, a cryogenic hydrogen (or
deuterium) target, and a superconducting, toroidal magnetic spectrometer
equipped with plastic scintillation and aerogel Cerenkov detectors, as well as
fast readout electronics for the measurement of individual events. The overall
design and performance of this experimental system is discussed.Comment: Submitted to Nuclear Instruments and Method
The Fueling and Evolution of AGN: Internal and External Triggers
In this chapter, I review the fueling and evolution of active galactic nuclei
(AGN) under the influence of internal and external triggers, namely intrinsic
properties of host galaxies (morphological or Hubble type, color, presence of
bars and other non-axisymmetric features, etc) and external factors such as
environment and interactions. The most daunting challenge in fueling AGN is
arguably the angular momentum problem as even matter located at a radius of a
few hundred pc must lose more than 99.99 % of its specific angular momentum
before it is fit for consumption by a BH. I review mass accretion rates,
angular momentum requirements, the effectiveness of different fueling
mechanisms, and the growth and mass density of black BHs at different epochs. I
discuss connections between the nuclear and larger-scale properties of AGN,
both locally and at intermediate redshifts, outlining some recent results from
the GEMS and GOODS HST surveys.Comment: Invited Review Chapter to appear in LNP Volume on "AGN Physics on All
Scales", Chapter 6, in press. 40 pages, 12 figures. Typo in Eq 5 correcte
N-body simulations of gravitational dynamics
We describe the astrophysical and numerical basis of N-body simulations, both
of collisional stellar systems (dense star clusters and galactic centres) and
collisionless stellar dynamics (galaxies and large-scale structure). We explain
and discuss the state-of-the-art algorithms used for these quite different
regimes, attempt to give a fair critique, and point out possible directions of
future improvement and development. We briefly touch upon the history of N-body
simulations and their most important results.Comment: invited review (28 pages), to appear in European Physics Journal Plu
An Integrated TCGA Pan-Cancer Clinical Data Resource to Drive High-Quality Survival Outcome Analytics
For a decade, The Cancer Genome Atlas (TCGA) program collected clinicopathologic annotation data along with multi-platform molecular profiles of more than 11,000 human tumors across 33 different cancer types. TCGA clinical data contain key features representing the democratized nature of the data collection process. To ensure proper use of this large clinical dataset associated with genomic features, we developed a standardized dataset named the TCGA Pan-Cancer Clinical Data Resource (TCGA-CDR), which includes four major clinical outcome endpoints. In addition to detailing major challenges and statistical limitations encountered during the effort of integrating the acquired clinical data, we present a summary that includes endpoint usage recommendations for each cancer type. These TCGA-CDR findings appear to be consistent with cancer genomics studies independent of the TCGA effort and provide opportunities for investigating cancer biology using clinical correlates at an unprecedented scale. Analysis of clinicopathologic annotations for over 11,000 cancer patients in the TCGA program leads to the generation of TCGA Clinical Data Resource, which provides recommendations of clinical outcome endpoint usage for 33 cancer types
Adrenal glands of Spix's yellow-toothed cavy (Galea spixii, Wagler, 1831): morphological and morphometric aspects
Portal Vein Embolization is Associated with Reduced Liver Failure and Mortality in High-Risk Resections for Perihilar Cholangiocarcinoma
Background: Preoperative portal vein embolization (PVE) is frequently used to improve future liver remnant volume (FLRV) and to reduce the risk of liver failure after major liver resection. Objective: This paper aimed to assess postoperative outcomes after PVE and resection for suspected perihilar cholangiocarcinoma (PHC) in an international, multicentric cohort. Methods: Patients undergoing resection for suspected PHC across 20 centers worldwide, from the year 2000, were included. Liver failure, biliary leakage, and hemorrhage were classified according to the respective International Study Group of Liver Surgery criteria. Using propensity scoring, two equal cohorts were generated using matching parameters, i.e. age, sex, American Society of Anesthesiologists classification, jaundice, type of biliary drainage, baseline FLRV, resection type, and portal vein resection. Results: A total of 1667 patients were treated for suspected PHC during the study period. In 298 patients who underwent preoperative PVE, the overall incidence of liver failure and 90-day mortality was 27% and 18%, respectively, as opposed to 14% and 12%, respectively, in patients without PVE (p < 0.001 and p = 0.005). After propensity score matching, 98 patients were enrolled in each cohort, resulting in similar baseline and operative characteristics. Liver failure was lower in the PVE group (8% vs. 36%, p < 0.001), as was biliary leakage (10% vs. 35%, p < 0.01), intra-abdominal abscesses (19% vs. 34%, p = 0.01), and 90-day mortality (7% vs. 18%, p = 0.03). Conclusion: PVE before major liver resection for PHC is associated with a lower incidence of liver failure, biliary leakage, abscess formation, and mortality. These results demonstrate the importance of PVE as an integral component in the surgical treatment of PHC
The effect of contaminants on the application of polyamine functionalised ion exchange resins for uranium extraction from sulfate based mining process waters
Three in-house produced polyamine functionalised ion exchange resins and Purolite S985 (a commercial ion exchange resin) have been assessed for their ability to extract UO22+ from a variety of aqueous matrices applicable to current and potential future uranium mining processes. The uptake of common contaminant species in uranium processing liquors at variable acid concentrations has been assessed, with Al3+ and MoO42− showing the most extraction, with AsO43−, Eu3+ and Fe3+ showing extractions >10% at low [H+]. Extraction of MoO42−, AsO43−, Eu3+ and Fe3+ was seen to decrease with increasing [H+]. The impact of increasing [Cl−] on UO22+ and Fe3+ extraction has been determined. Fe3+ showed low extractions by all resins, with no dependence on [Cl−]. In contrast, increasing suppression of UO22+ uptake was seen with increasing [Cl−] up to 80 g L−1, with extraction remaining constant beyond this [Cl−]. At high [Cl−] (>50 g L−1) Purolite S985 was seen to remove UO22+ from solution more effectively than all synthesised polyamine resins. The presence of Fe3+ in solution was seen to suppress UO22+ uptake by around 10% when [Fe3+]/[UO22+] increased from 0 to 2. Fe3+ extraction by all studied resins was promoted by the presence of UO22+ in solution. This was most prevalent with Purolite S985, with an extraction of 30% for [Fe3+]/[UO22+] = 2 by Purolite S985. All resins were tested using a process water from a uranium mine and have shown an ability to selectively extract UO22+ from such solutions, with the best synthetic resin recovering 15.7% more uranium than Purolite S985
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