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Abstract  

Instrumental neutron activation analysis (INAA) using Ghana's low flux Miniature Neutron Source Reactor (MNSR) was utilized to analyze twelve trace elements namely Al, Au, As, Br, Cl, Ga, K, Mn, Mo, Na, V and Zn in seven different crude petroleum samples from different oil fields in the Niger/Delta region of Nigeria. The results obtained indicate that the concentration ranges of the elements show some variability in compositions and concentrations from field to field. The measured low As and S contents of the samples suggest that the crude oils have low hazardous impact on the environment.

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Abstract  

Fluorine surface contamination and depth profiles were studied using the19F(p, p')19F resonance reaction. Fluorine implanted silicon samples as well as ZrNb plates and Cr–Al layers after a HF-treatment have been examined. The resonance strengths of the narrow 1088 keV resonance were estimated.

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Abstract  

Hydrogen surface contamination and depth profiles can be measured by the resonant nuclear reactions1H(19F, )16O and1H(15N, )12C. The method was applied to study hydrogen-implanted silicon, amorphous silicon layers and silicon oxide films produced by anodic oxidation.

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Abstract  

Whole body nitrogen has been measured absolutely in male volunteers and patients by in-vivo neutron activation analysis using whole body hydrogen as an internal standard. The 10.8 MeV and 2.2 MeV prompt gamma rays from nitrogen and hydrogen respectively give a result reproducible to 4% for a dose of 100 mRem. Whole body potassium measured by whole body counting natural40K and whole body nitrogen have been correlated in normal adult males and patients. In the normals the correlation coefficient was 0.96 with coefficient of variation 4%. In the patients these parameters were 0.92 and 8% in 140 measurements. The ratio of N/K increased significantly as the degree of clinical wasting progressed.

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Summary

Genotoxic impurities can be described as impurities that can induce genetic mutations and chromosomal breaks, or that damage the genetic information within a cell, which may lead to cancer. The European Medical Agency (EMA) and the United States Food and Drug Administration (US FDA) have set a threshold of toxicological concern (TTC) of genotoxic impurities 1.5 µg per day. In a continuous effort to develop an analytical method for the estimation of genotoxic impurities in quetiapine fumarate, a sensitive, simple, and precise high-performance thin-layer chromatography method has been developed and validated for the determination of 2-nitrophenyl (phenyl)sulfane as a genotoxic impurity at trace levels. The limits of detection (LOD) for quetiapine fumarate and 2-nitrophenyl (phenyl)sulfane were found to be 5.11 and 15.5 ng per band, whereas the limits of quantification (LOQ) were observed 0.09 and 0.3 ng per band, respectively. The calibration curve for 2-nitrophenyl (phenyl)sulfane was linear over the concentration range of 10 to 50 ng per band. The method was found to be specific, precise, linear, and accurate for the estimation of 2-nitrophenyl (phenyl)sulfane at trace levels in quetiapine fumarate.

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Journal of Behavioral Addictions
Authors:
William Van Gordon
,
Edo Shonin
,
Thomas J. Dunn
,
Javier Garcia-Campayo
,
Marcelo M. P. Demarzo
, and
Mark D. Griffiths

Background and aims

Workaholism is a form of behavioral addiction that can lead to reduced life and job satisfaction, anxiety, depression, burnout, work–family conflict, and impaired productivity. Given the number of people affected, there is a need for more targeted workaholism treatments. Findings from previous case studies successfully utilizing second-generation mindfulness-based interventions (SG-MBIs) for treating behavioral addiction suggest that SG-MBIs may be suitable for treating workaholism. This study conducted a controlled trial to investigate the effects of an SG-MBI known as meditation awareness training (MAT) on workaholism.

Methods

Male and female adults suffering from workaholism (n = 73) were allocated to MAT or a waiting-list control group. Assessments were performed at pre-, post-, and 3-month follow-up phases.

Results

MAT participants demonstrated significant and sustained improvements over control-group participants in workaholism symptomatology, job satisfaction, work engagement, work duration, and psychological distress. Furthermore, compared to the control group, MAT participants demonstrated a significant reduction in hours spent working but without a decline in job performance.

Discussion and conclusions

MAT may be a suitable intervention for treating workaholism. Further controlled intervention studies investigating the effects of SG-MBIs on workaholism are warranted.

Open access
Journal of Behavioral Addictions
Authors:
Thomas McLaughlin
,
Kenneth Blum
,
Bruce Steinberg
,
Edward J. Modestino
,
Lyle Fried
,
David Baron
,
David Siwicki
,
Eric R. Braverman
, and
Rajendra D. Badgaiyan

Background

Addictive-like behaviors (e.g., hoarding and shopping) may be the result of the cumulative effects of dopaminergic and other neurotransmitter genetic variants as well as elevated stress levels. We, therefore, propose that dopamine homeostasis may be the preferred goal in combating such challenging and unwanted behaviors, when simple dopaminergic activation through potent agonists may not provide any resolution.

Case presentation

C.J. is a 38-year-old, single, female, living with her mother. She has a history of substance use disorder as well as attention deficit hyperactivity disorder, inattentive type. She had been stable on buprenorphine/naloxone combination and amphetamine, dextroamphetamine mixed salts for many years when unexpectedly she lost her job for oversleeping and not calling into work. KB200z (a pro-dopamine compound) was added to her regimen for complaints of low drive and motivation. After taking this nutraceutical for 4 weeks, she noticed a marked improvement in her mental status and many behaviors. She noted that her shopping and hoarding addictions had appreciably decreased. Furthermore, her lifelong history of terrifying lucid dreams was eliminated. Finally, she felt more in control; her locus of control shifted from external to more internal.

Discussion

The hypothesis is that C.J.’s reported, behavioral, and psychological benefits resulted from the pro-dopamine-regulating effect of KB220Z across the brain reward system.

Conclusions

This effect, we surmise, could be the result of a new dopamine balance, across C.J.’s brain reward system. Dopamine homeostasis is an effect of KB220Z seen in both animal and human placebo-controlled fMRI experiments.

Open access
Journal of Psychedelic Studies
Authors:
John M. Clifton
,
Annabelle M. Belcher
,
Aaron D. Greenblatt
,
Christopher M. Welsh
,
Thomas O. Cole
, and
Alan K. Davis

Abstract

Background and aims

There is growing evidence that psilocybin, a serotonergic psychedelic substance, may be useful in the treatment of substance use disorders. However, there is a lack of data on the beliefs and attitudes towards psilocybin amongst Black individuals diagnosed with Opioid Use Disorder (OUD). This study characterized psilocybin use patterns and perception of risk amongst a cohort of Black individuals diagnosed with OUD.

Methods

Using a convenience sampling approach, patients were recruited from an urban methadone treatment program and paid five dollars to complete an anonymous phone-based survey.

Results

Twenty-eight patients participated (mean age 53.8; N = 28; 35.7% female). Most (N = 23; 82.1%) had “heard of” psilocybin mushrooms before taking the survey, but only five (N = 5; 17.8%) had ever used them. More than 80% perceived a risk or were “unsure” of the risk for sixteen of the seventeen items queried about psilocybin. Approximately half (N = 15; 53.6%) were willing to try therapy incorporating psilocybin and half (N = 14; 50%) said they would be more likely to try if it were FDA approved for OUD. Most (N = 18; 64.3%) preferred to stay on methadone treatment alone, 32.1% (N = 9) wanted to try treatment with both psilocybin and methadone, and only one participant opted for psilocybin treatment without methadone.

Conclusion

Many Black individuals with Opioid Use Disorder perceive psilocybin as dangerous and may be hesitant to try psilocybin treatment. Culturally informed treatment models, educational interventions and community outreach programs should be developed to increase racial/ethnic minority representation in psilocybin research and treatment.

Open access
Journal of Radioanalytical and Nuclear Chemistry
Authors:
D. Robertson
,
A. Schilk
,
K. Abel
,
E. Lepel
,
C. Thomas
,
S. Pratt
,
E. Cooper
,
P. Hartwig
, and
R. Killey

Abstract  

In order to more accurately predict the rates and mechanisms of radionuclide migration from lowlevel waste disposal facilities via groundwater transport, ongoing studies are being conducted at field sites at Chalk River Laboratories to identify and characterize the chemical speciation of mobile, long-lived radionuclides migrating in groundwaters. Large-volume water sampling techniques are being utilized to separate and concentrate radionuclides into particulate, cationic, anionic, and nonionic chemical forms. Most radionuclides are migrating as soluble, anionic species which appear to be predominately organoradionuclide complexes. Laboratory studies utilizing anion exchange chromatography have separated several anionically complexed radionuclides, e.g.,60Co and106Ru, into a number of specific compounds or groups of compounds. Large-volume ultra-filtration experiments have shown that significant fractions of the radionuclides are being transported in these groundwaters in the form of macromolecules having molecular weights ranging from less than 3,000 to 100,000.

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Acta Chromatographica
Authors:
A. B. Thomas
,
U. B. Chavan
,
R. K. Nanda
,
L. P. Kothapalli
,
S. N. Jagdale
,
S. B. Dighe
, and
A. D. Deshpande

Summary

Simultaneous analysis of atenolol (Atn), hydrochlorothiazide (Hctz) and losartan potassium (Los) in solid dosage forms has been achieved by reversed-phase high-performance liquid chromatography on a C18 column with a 0.035 M potassium dihydrogen orthophosphate-acetonitrile gradient as mobile phase and UV detection at 225 nm. The retention times for Atn, Hctz, and Los were 2.91, 4.75, and 7.52 min, respectively, with mean recoveries of 99.67, 99.89, and 100.69%. The method was validated in accordance with ICH guidelines. Because of its simplicity and high precision and accuracy, the method can be used for analysis of atenolol, hydrochlorothiazide and losartan potassium in pharmaceutical preparations.

Open access