Search Results

You are looking at 1 - 8 of 8 items for

  • Author or Editor: P. Mason x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract  

Two programmes of work are described involving the measurement of environmental pollution over periods from two hours to many years. The long period measurements are deduced from neutron activation analysis of whole wood samples taken from individual tree rings for trees grown in various locations, and some results for cadmium, antimony and germanium levels are reported. In a second series of experiments the concentration of airborne particulate matter is being measured using a moving filter (streak sampler) technique to give a continuous record with two hour resolution. The filter samples are being analysed by proton induced X-ray emission (PIXE) and preliminary data is presented.

Restricted access

Background

A substantial number of people worldwide suffer from mental health problems during their lifetime. First-line treatments are not effective for everybody. Recent studies suggest that psychedelic drugs have high therapeutic potential for a variety of mental disorders.

Aims

This survey study aimed to assess the tendency of psychedelic users to self-medicate with psychedelics and to compare the effectiveness of self-administered psychedelics to treat their disorder and the treatment offered by a medical professional.

Methods and results

In total, 1,967 respondents consented were ≥18 years and completed the questionnaire. The mean (±SD) age was 25.9 (8.7); 79% were males, 20% females, and 1% classified themselves as “other.” Almost half of the respondents (46%) indicated to have suffered/to be suffering from a mental disorder, with 77% being diagnosed by a medical professional. In 99% of the diagnosed cases, the treatment was offered; 77% searched for treatments outside a medical professional’s recommendation with 81% who had used/were using psychedelics to treat/cure symptoms. Self-administered psychedelic treatment had a higher likelihood of being efficacious, with higher symptoms reduction and larger quality of life improvement compared to treatment offered by a medical professional.

Conclusions

Lifetime prevalence of psychopathologies in the current sample of psychedelic drug users seemed to be higher than in the general population. Self-medication with psychedelics was not highly frequent; although when it occurred, it was rated as significantly more effective as treatment offered by a medical professional. Current findings support research exploring the potential of psychedelics in the treatment of psychopathologies.

Open access

Abstract  

Particle-induced X-ray emission (PIXE) analysis of the lighter elements in time-resolved air particulate deposits has been carried out. Minimum detection limits have been determined for 1.0, 2.0 and 3.5 MeVprotons. Quantitative PIXE analysis results, obtained with 2 MeV protons, are given for temporal variations in the elemental concentrations of Na, Al, Si, S, Cl, K, Ca and Fe. Rutherford backscattering (RBS) spectra were taken simultaneously with the PIXE spectra to provide information on lead concentrations and deposit thicknesses. The experimental problems associated with the quantitative analysis of light elements on cellulose acetate filters are described. The relationship between these results and meteorological data is discussed.

Restricted access

Abstract  

The characterized concentrations of 24 impurity elements in New Brunswick Laboratory (NBL) Certified Reference Material (CRM) 124 were reevaluated. A provisional certificate of analysis was issued in September 1983 based upon the “as prepared” values (gravimetric mixing). The provisional certificate does not state uncertainties for the characterized values, or estimate the degree of homogeneity. Since release of the provisional certificate of analysis various laboratories have reported analytical results for CRM 124. Based upon the reported data a re-evaluation of the characterized values with an estimate of their uncertainties was performed in this work. An assessment of the degree of homogeneity was included. The overall difference between the re-evaluated values for the 24 impurity elements and the “as prepared” values from the provisional certificate of analysis is negligible compared to the uncertainties. Therefore, NBL will establish the “as prepared” values as the certified values and use the derived uncertainties from this work for the uncertainties of the certified values. The traceability of the “as prepared” values was established by the gravimetric mixing procedure employed during the preparation of the CRM. NBL further recommends a minimum sample size of 1 g of the CRM material to ensure homogeneity. Samples should be dried by heating up to 110 °C for one hour before use.

Restricted access

We present and validate simple mesofluidic devices for producing monodisperse droplets and materials. The significance of this work is a demonstration that simple and complex droplet formulations can be prepared uniformly using off-the-shelf small-diameter tubing, barbed tubing adapters, and needles. With these simple tools, multiple droplet-forming devices and a new particle concentrator were produced and validated. We demonstrate that the droplet-forming devices could produce low-dispersity particles from 25 to 1200 Km and that these results are similar to results from more complicated devices. Through a study of the fluid dynamics and a dimensional analysis of the data, we have correlated droplet size with two dimensionless groups, capillary number and viscosity ratio. The flowfocusing device is more sensitive to both parameters than the T-junction geometry. The modular character of our mesofluidic devices allowed us to rapidly assemble compound devices that use flow-focusing and T-junction devices in series to create complex droplet-in-microcapsule materials. This work demonstrates that flow chemistry does not require complicated tools, and an inexpensive tool-kit can allow anyone with interest to enter the field.

Open access

Abstract  

The International Organization for Standardization (ISO) Guide to the expression of Uncertainty in Measurement (GUM) was developed to meet the demand for a standardized way of evaluating and expressing uncertainties. The Davies and Gray (D&G) titrimetry method is routinely used in nuclear safeguards for uranium accountability measurement and a statement of the uncertainty that can reasonably be attributed to the measured assay value is therefore of importance. A mathematical model for an uncertainty evaluation of D&G measurements in compliance with ISO GUM is presented. This is illustrated by a numerical example and the utilization of the uncertainty budget is explored.

Restricted access
Journal of Radioanalytical and Nuclear Chemistry
Authors: V. Spate, J. Morris, T. Nichols, C. Baskett, M. Mason, T. Horsman, P. Horn-Ross, A. Shiau, and I. McDougall

Abstract  

The literature on the relationship between diet and thyroid cancer (TC) risk and the higher incidence of TC among Asian immigrants to the US compared to second and third generation subgroups has prompted epidemiologists to hypothesize that increased levels of iodine consumption may be associated with TC risk, particularly among persons with a history of clinical or subclinical thyroid dysfunction. At the University of Missouri Research Reactor (MURR), we have applied epiboron neutron activation analysis to investigate human nails as a dietary monitor for iodine. Preliminary studies have indicated a positive correlation between dietary iodine intake and the concentration of iodine in toenails. However, these studies are confounded by high iodine levels (up to 30 ppm) in approximately 5% of the nails studied. We hypothesize that, in the subjects we have studied, the high iodine levels may be due to iodine-containing medications, in particular contrast-agents containing iopamidol. This paper will report on longitudinal studies using contrast agent subjects who were followed-up for almost two years compared to a longitudinal control and a population mean. Based on this study, we suggest that iodine-containing contrast agents contaminate nail samples via non-specific binding in the short term followed by incorporation in the nail as a result of absorption.

Restricted access
Journal of Radioanalytical and Nuclear Chemistry
Authors: V. Spate, J. Morris, S. Chickos, C. Baskett, M. Mason, T. Cheng, C. Reams, C. West, C. Furnee, W. Willett, and P. Horn-Ross

Abstract  

An epithermal instrumental neutron activation analysis (EINAA) method, using a boron nitride irradiation capsule compatible with use in the University of Missouri Research Reactor pneumatic-tube irradiation facility, has been developed for the analysis of iodine in human nails. The principal objective was to determine if the nail could be used as a means of monitoring dietary intake of iodine. The EINAA method was used to analyze nails from subjects having iodine intakes that could be qualitatively differentiated. Iodine concentrations in nails from these subjects were positively correlated with apparent iodine intake.

Restricted access