Fluorogenic Membrane Overlays to Enumerate Total and Fecal Escherichia coli and Total Vibrionaceae in Shellfish and Seawater

Three assays were developed to enumerate total and fecal Escherichia coli and total Vibrionaceae in shellfish, seawater, and other foods and environmental samples. Assays involve membrane overlays of overnight colonies on nonselective agar plates to detect β-glucuronidase and lysyl aminopeptidase activities for E. coli and Vibrionaceae, respectively. Cellulose membranes containing the substrates 4-methylumbeferyl-β-D-glucuronide (MUG) produced a bright blue fluorescence when overlaid onto E. coli, while L-lysyl-7-amino-4-trifluoromethylcoumarin produced green fluorescent foci when overlaid onto Vibrionaceae family members. A multiplex assay was also developed for simultaneously enumerating total E. coli and total Vibrionaceae in oysters and seawater. Overall, 65% of overlaid E. coli (non-O157:H7) were MUG-positive, compared with 62% as determined by the most-probable-number-MUG assay. The overlays are rapid, simple, and cost effective for quantification purposes. This research provides practical alternatives for monitoring bacterial indicators and potential pathogens in complex samples, including molluscan shellfish

Atypical presentation of neuronal ceroid lipofuscinosis type 8 in a sibling pair and review of the eye findings and neurological features.

Purpose:To report atypical presentation of neuronal ceroid lipofuscinoses type 8 (CLN8) to the eye clinic and review clinical features of CLN8. Observations:Detailed eye exam by slit lamp exam, indirect ophthalmoscopy, fundus photography, optical coherence tomography, visual fields and electroretinogram (ERG). Molecular genetic testing using Next Generation Sequencing panel (NGS) and array Comparative Genomic Hybridization (aCGH).The siblings in this study presented to the eye clinic with retinitis pigmentosa and cystoid macular edema, and a history of seizures but no severe neurocognitive deficits or regression. Genetic testing identified a c.200C > T (p.A67V) variant in the CLN8 gene and a deletion encompassing the entire gene. Electron microscopy of lymphocytes revealed fingerprint inclusions in both siblings. Conclusions:and Importance: Pathogenic variants in CLN8 account for the retinitis pigmentosa and seizures in our patients however, currently, they do not have regression or neurocognitive decline. The presentation of NCL can be very diverse and it is important for ophthalmologists to consider this in the differential diagnosis of retinal disorders with seizures or other neurological features. Molecular genetic testing of multiple genes causing isolated and syndromic eye disorders using NGS panels and aCGH along with additional complementary testing may often be required to arrive at a definitive diagnosis

The factors affecting outdoor recreation experiences

The notion of a recreation demand hierarchy was first proposed by Drs. Driver and Brown in 1978. The hierarchy comprised the demands for activities, demands for settings in which to undertake those activities, demands for the experiences flowing from participation, and demands for the benefits that flow from satisfying experiences. Except for the consideration of benefits, this concept is inherent in the Recreation Opportunity Spectrum (ROS) planning system which presupposes that the demand for different experiences can be satisfied by the supply of a variety of settings on a primitive-to-urban continuum. This presupposition relies on the existence of an association between recreation settings and the experiences that flow from visits to those settings. That such an association exists, at least in an empirically measurable sense, has been questioned in several recent studies by United States of America recreation research workers who have found only limited empirical support for the existence of such an association. This thesis has, in part, characterised experiences at a variety of settings using the Recreation Experience Preference (REP) item pools developed by Driver. The importance of both the REP items and individual setting attributes were measured on modified Likert scales and associations sought between the attributes and experiences. Also considered were the effects of respondent’s activity, group size, group composition and life cycle stage on an association between setting and experience. Respondents were also asked to nominate the ways in which they would modify the setting in which they were interviewed to make it more ideal. Results showed that settings and experiences are associated and that this is affected to varying amounts by the respondent’s activity, group size, group composition and life cycle stage. No consistent desired modifications to settings to make them more ideal were found. These results suggested merit in the development of new experience items that could better explain the setting and experience association. After development and testing, the new items were included in a mail-back questionnaire to respondents involved in the activities of bird watching and angling. The questionnaire was also designed to explore the potential effects of specialisation, commitment and experience use history on the experiences desired or expected from participation. The results made it apparent that greater empirical support and explanation of the setting and experience association can be achieved through the development and use of experience items that refer more specifically to the recreation setting. It was also established that the experiences desired or expected from recreation participation would vary according to levels of specialisation, commitment and experience use history

Tuning of emission color for blue dendrimer blend light-emitting diodes

Published versio

High-Redshift SDSS Quasars with Weak Emission Lines

We identify a sample of 74 high-redshift quasars (z>3) with weak emission lines from the Fifth Data Release of the Sloan Digital Sky Survey and present infrared, optical, and radio observations of a subsample of four objects at z>4. These weak emission-line quasars (WLQs) constitute a prominent tail of the Lya+NV equivalent width distribution, and we compare them to quasars with more typical emission-line properties and to low-redshift active galactic nuclei with weak/absent emission lines, namely BL Lac objects. We find that WLQs exhibit hot (T~1000 K) thermal dust emission and have rest-frame 0.1-5 micron spectral energy distributions that are quite similar to those of normal quasars. The variability, polarization, and radio properties of WLQs are also different from those of BL Lacs, making continuum boosting by a relativistic jet an unlikely physical interpretation. The most probable scenario for WLQs involves broad-line region properties that are physically distinct from those of normal quasars.Comment: Updated to match version published in ApJ. 20 pages, 12 figure

Candidate Type II Quasars from the SDSS: III. Spectropolarimetry Reveals Hidden Type I Nuclei

We have conducted spectropolarimetry of 12 type II (obscured) quasar candidates selected from the spectroscopic database of the Sloan Digital Sky Survey based on their emission line properties. Polarization was detected in all objects, with nine being highly polarized (> 3%) and with polarization reaching as high as 17% in two objects. Broad lines were detected in the polarized spectra of five objects. These observations prove beyond a reasonable doubt that the objects in our sample are indeed type II quasars, in that they harbor luminous UV-excess AGNs in their centers and that the direct view to the AGN is highly obscured. For three of the objects in this paper, we have obtained HST images in three bands. The HST observations, combined with the spectropolarimetry data, imply that scattering off material outside the obscuration plane is the dominant polarization mechanism. In all three objects the sizes of scattering regions are a few kpc. For one object, the extent of the scattering region, coupled with the characteristics of the polarized spectrum, argue strongly that dust scattering rather than electron scattering dominates the polarized light. Our observations are well-described by the basic orientation-based unification model of toroidal obscuration and off-plane scattering, implying that the model can be extended to include at least some high-luminosity AGNs.Comment: 31 pages including 4 b/w pictures, 1 color HST image and 2 tables. Submitted to AJ on Sept 26, accepted for March 2005. Minor modifications to match the accepted versio

Nondispersive hole transport in a spin-coated dendrimer film measured by the charge-generation-layer time-of-flight method

Published versio

Conjugated dendrimers: A modular approach to materials for full colour displays

Conjugated dendrimers provide an excellent molecular architecture for tuning material properties for organic light emitting diodes. Here we demonstrate a modular approach allowing highly efficient fluorescent and phosphorescent emissive chromophores to be used to make red, green and blue solution-processed light emitting diodes. The choice of a common dendritic architecture ensures good solubility and film forming properties irrespective of the choice of core unit. In addition, this architecture allows blending of dendrimers with different cores without phase separation. We show that blending provides a simple but powerful way of tuning the colour of dendrimer LEDs from deep blue to blue-green, and from green to red with little impact on the device properties

Pharmacologic inhibition of S-nitrosoglutathione reductase protects against experimental asthma in BALB/c mice through attenuation of both bronchoconstriction and inflammation

BACKGROUND: S-nitrosoglutathione (GSNO) serves as a reservoir for nitric oxide (NO) and thus is a key homeostatic regulator of airway smooth muscle tone and inflammation. Decreased levels of GSNO in the lungs of asthmatics have been attributed to increased GSNO catabolism via GSNO reductase (GSNOR) leading to loss of GSNO- and NO- mediated bronchodilatory and anti-inflammatory actions. GSNOR inhibition with the novel small molecule, N6022, was explored as a therapeutic approach in an experimental model of asthma. METHODS: Female BALB/c mice were sensitized and subsequently challenged with ovalbumin (OVA). Efficacy was determined by measuring both airway hyper-responsiveness (AHR) upon methacholine (MCh) challenge using whole body plethysmography and pulmonary eosinophilia by quantifying the numbers of these cells in the bronchoalveolar lavage fluid (BALF). Several other potential biomarkers of GSNOR inhibition were measured including levels of nitrite, cyclic guanosine monophosphate (cGMP), and inflammatory cytokines, as well as DNA binding activity of nuclear factor kappa B (NFκB). The dose response, onset of action, and duration of action of a single intravenous dose of N6022 given from 30 min to 48 h prior to MCh challenge were determined and compared to effects in mice not sensitized to OVA. The direct effect of N6022 on airway smooth muscle tone also was assessed in isolated rat tracheal rings. RESULTS: N6022 attenuated AHR (ED(50) of 0.015 ± 0.002 mg/kg; Mean ± SEM) and eosinophilia. Effects were observed from 30 min to 48 h after treatment and were comparable to those achieved with three inhaled doses of ipratropium plus albuterol used as the positive control. N6022 increased BALF nitrite and plasma cGMP, while restoring BALF and plasma inflammatory markers toward baseline values. N6022 treatment also attenuated the OVA-induced increase in NFκB activation. In rat tracheal rings, N6022 decreased contractile responses to MCh. CONCLUSIONS: The significant bronchodilatory and anti-inflammatory actions of N6022 in the airways are consistent with restoration of GSNO levels through GSNOR inhibition. GSNOR inhibition may offer a therapeutic approach for the treatment of asthma and other inflammatory lung diseases. N6022 is currently being evaluated in clinical trials for the treatment of inflammatory lung disease