840 research outputs found
Effect of Ozone, Clothing, Temperature, and Humidity on the Total OH Reactivity Emitted from Humans
People influence indoor air chemistry through their chemical emissions via breath and skin. Previous studies showed that direct measurement of total OH reactivity of human emissions matched that calculated from parallel measurements of volatile organic compounds (VOCs) from breath, skin, and the whole body. In this study, we determined, with direct measurements from two independent groups of four adult volunteers, the effect of indoor temperature and humidity, clothing coverage (amount of exposed skin), and indoor ozone concentration on the total OH reactivity of gaseous human emissions. The results show that the measured concentrations of VOCs and ammonia adequately account for the measured total OH reactivity. The total OH reactivity of human emissions was primarily affected by ozone reactions with organic skin-oil constituents and increased with exposed skin surface, higher temperature, and higher humidity. Humans emitted a comparable total mixing ratio of VOCs and ammonia at elevated temperature-low humidity and elevated temperature-high humidity, with relatively low diversity in chemical classes. In contrast, the total OH reactivity increased with higher temperature and higher humidity, with a larger diversity in chemical classes compared to the total mixing ratio. Ozone present, carbonyl compounds were the dominant reactive compounds in all of the reported conditions
Multicolour correlative imaging using phosphor probes
Correlative light and electron microscopy exploits the advantages of optical methods, such as multicolour probes and their use in hydrated live biological samples, to locate functional units, which are then correlated with structural details that can be revealed by the superior resolution of electron microscopes. One difficulty is locating the area imaged by the electron beam in the much larger optical field of view. Multifunctional probes that can be imaged in both modalities and thus register the two images are required. Phosphor materials give cathodoluminescence (CL) optical emissions under electron excitation. Lanthanum phosphate containing thulium or terbium or europium emits narrow bands in the blue, green and red regions of the CL spectrum; they may be synthesised with very uniform-sized crystals in the 10- to 50-nm range. Such crystals can be imaged by CL in the electron microscope, at resolutions limited by the particle size, and with colour discrimination to identify different probes. These materials also give emissions in the optical microscope, by
multiphoton excitation. They have been deposited on the surface of glioblastoma cells and imaged by CL. Gadolinium oxysulphide doped with terbium emits green photons by either ultraviolet or electron excitation. Sixty-nanometre crystals of this phosphor have been imaged in the atmospheric scanning electron microscope (JEOL ClairScope). This probe and microscope combination allow correlative imaging in hydrated samples. Phosphor probes should prove to be very useful in correlative light and electron microscopy, as fiducial
markers to assist in image registration, and in high/super resolution imaging studies
Near-Infrared Survey and Photometric Redshifts in the Extended GOODS-North field
We present deep and -band images in the extended Great Observatories
Origins Deep Survey-North (GOODS-N) field covering an area of 0.22
. The observations were taken using WIRCam on the 3.6-m Canada
France Hawaii Telescope (CFHT). Together with the reprocessed -band
image, the limiting AB magnitudes (in 2" diameter apertures) are
24.7, 24.2, and 24.4 AB mag in the , , and bands,
respectively. We also release a multi-band photometry and photometric redshift
catalog containing 93598 sources. For non-X-ray sources, we obtained a
photometric redshift accuracy with an outlier
fraction . For X-ray sources, which are mainly active galactic
nuclei (AGNs), we cross-matched our catalog with the updated 2M-CDFN X-ray
catalog from Xue et al. (2016) and found that 658 out of 683 X-ray sources have
counterparts. UV data are included in the photometric redshift
computation for the X-ray sources to give with
. Our approach yields more accurate photometric redshift estimates
compared to previous works in this field. In particular, by adopting AGN-galaxy
hybrid templates, our approach delivers photometric redshifts for the X-ray
counterparts with fewer outliers compared to the 3D-HST catalog, which fit
these sources with galaxy-only templates
Fenfluramine for Treatment-Resistant Seizures in Patients With Dravet Syndrome Receiving Stiripentol-Inclusive Regimens A Randomized Clinical Trial
IMPORTANCE Fenfluramine treatment may reduce monthly convulsive seizure frequency in
patients with Dravet syndrome who have poor seizure control with their current
stiripentol-containing antiepileptic drug regimens.
OBJECTIVE To determine whether fenfluramine reduced monthly convulsive seizure
frequency relative to placebo in patients with Dravet syndrome who were taking
stiripentol-inclusive regimens.
DESIGN, SETTING, AND PARTICIPANTS This double-blind, placebo-controlled, parallel-group
randomized clinical trial was conducted in multiple centers. Eligible patients were children
aged 2 to 18 years with a confirmed clinical diagnosis of Dravet syndrome who were receiving
stable, stiripentol-inclusive antiepileptic drug regimens.
INTERVENTIONS Patients with 6 or more convulsive seizures during the 6-week baseline
period were randomly assigned to receive fenfluramine, 0.4 mg/kg/d (maximum, 17 mg/d),
or a placebo. After titration (3 weeks), patients’ assigned dosages were maintained for
12 additional weeks. Caregivers recorded seizures via a daily electronic diary.
MAIN OUTCOMES AND MEASURES The primary efficacy end point was the change in mean
monthly convulsive seizure frequency between fenfluramine and placebo during the
combined titration and maintenance periods relative to baseline.
RESULTS A total of 115 eligible patients were identified; of these, 87 patients (mean [SD], age
9.1 [4.8] years; 50 male patients [57%]; mean baseline frequency of seizures, approximately
25 convulsive seizures per month) were enrolled and randomized to fenfluramine,
0.4 mg/kg/d (n = 43) or placebo (n = 44). Patients treated with fenfluramine achieved a
54.0% (95% CI, 35.6%-67.2%; P < .001) greater reduction in mean monthly convulsive
seizure frequency than those receiving the placebo. With fenfluramine, 54% of patients
demonstrated a clinically meaningful (50%) reduction in monthly convulsive seizure
frequency vs 5% with placebo (P < .001). The median (range) longest seizure-free interval
was 22 (3.0-105.0) days with fenfluramine and 13 (1.0-40.0) days with placebo (P = .004).
The most common adverse events were decreased appetite (19 patients taking fenfluramine
[44%] vs 5 taking placebo [11%]), fatigue (11 [26%] vs 2 [5%]), diarrhea (10 [23%] vs 3 [7%]),
and pyrexia (11 [26%] vs 4 [9%]). Cardiac monitoring demonstrated no clinical or
echocardiographic evidence of valvular heart disease or pulmonary arterial hypertension.
CONCLUSIONS AND RELEVANCE Fenfluramine demonstrated significant improvements in
monthly convulsive seizure frequency in patients with Dravet syndrome whose conditions
were insufficiently controlled with stiripentol-inclusive antiepileptic drug regimens.
Fenfluramine was generally well tolerated. Fenfluramine may represent a new treatment
option for Dravet syndrome.
TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT0292689
Linking a dermal permeation and an inhalation model to a simple pharmacokinetic model to study airborne exposure to di(n-butyl) phthalate
Six males clad only in shorts were exposed to high levels of airborne di(n-butyl) phthalate (DnBP) and diethyl phthalate (DEP) in chamber experiments conducted in 2014. In two 6 h sessions, the subjects were exposed only dermally while breathing clean air from a hood, and both dermally and via inhalation when exposed without a hood. Full urine samples were taken before, during, and for 48 h after leaving the chamber and measured for key DnBP and DEP metabolites. The data clearly demonstrated high levels of DnBP and DEP metabolite excretions while in the chamber and during the first 24 h once leaving the chamber under both conditions. The data for DnBP were used in a modeling exercise linking dose models for inhalation and transdermal permeation with a simple pharmacokinetic model that predicted timing and mass of metabolite excretions. These models were developed and calibrated independent of these experiments. Tests included modeling of the “hood-on” (transdermal penetration only), “hood-off” (both inhalation and transdermal) scenarios, and a derived “inhalation-only” scenario. Results showed that the linked model tended to duplicate the pattern of excretion with regard to timing of peaks, decline of concentrations over time, and the ratio of DnBP metabolites. However, the transdermal model tended to overpredict penetration of DnBP such that predictions of metabolite excretions were between 1.1 and 4.5 times higher than the cumulative excretion of DnBP metabolites over the 54 h of the simulation. A similar overprediction was not seen for the “inhalation-only” simulations. Possible explanations and model refinements for these overpredictions are discussed. In a demonstration of the linked model designed to characterize general population exposures to typical airborne indoor concentrations of DnBP in the United States, it was estimated that up to one-quarter of total exposures could be due to inhalation and dermal uptake
Observation of Two Narrow States Decaying into and
We report the first observation of two narrow charmed strange baryons
decaying to and , respectively, using data from
the CLEO II detector at CESR. We interpret the observed signals as the
and , the symmetric partners
of the well-established antisymmetric and .
The mass differences and
are measured to be and
, respectively.Comment: 11 pages, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
Measurement of the Partila Width and Form Factor Parameters
We have studied the decay , where . From a fit to the differential decay rate we measure the
rate normalization and form factor slope
, and, using measured values of , find . The resulting branching
fractions are and .
The form factor parameters are in agreement with those measured in decays, as predicted by heavy quark effective theory.Comment: 11 pages, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
Flavor-Specific Inclusive B Decays to Charm
We have measured the branching fractions for B -> D_bar X, B -> D X, and B ->
D_bar X \ell^+ \nu, where ``B'' is an average over B^0 and B^+, ``D'' is a sum
over D^0 and D^+, and``D_bar'' is a sum over D^0_bar and D^-. From these
results and some previously measured branching fractions, we obtain Br(b -> c
c_bar s) = (21.9 3.7)%, Br(b -> s g) K^-
\pi^+) = (3.69 0.20)%. Implications for the ``B semileptonic decay
problem'' (measured branching fraction being below theoretical expectations)
are discussed. The increase in the value of Br(b -> c c_bar s) due to eliminates 40% of the discrepancy.Comment: 12 page postscript file, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
- …