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We show that in almost every random graph process, the hitting time for havingk edge-disjoint spanning trees equals the hitting time for having minimum degreek.

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Abstract  

211Pb and its daughters are produced in a generator system which utilizes the distillation of the intermediate daughter219Rn from223Ra. The radium is precipitated as the stearate to isolate the parent while allowing the gaseous daughter to emanate. While the yield of the system is low, approximately 10%, the radionuclidic purity is extremely high. No measurable223Ra is found in the product.223Ra is separated from its parent,227Ac, by cation exchange.

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Summary  

In the present work, we investigated the immunological behavior of bothropstoxin-1, a K49 phospholipase from Bothrops jararacussu, and of ovalbumin before and after irradiation with 60Co g-rays. Isogenic mice were immunized with either native or irradiated proteins. The circulating antibodies were isotyped and titrated by ELISA. Results indicate that irradiated proteins were immunogenic and the antibodies elicited by them were able to recognize the native proteins in ELISA. Data also indicate that the irradiated protein induced higher titers of IgG2a and IgG2b, suggesting that Th1 cells were predominantly involved in the immune response. Structural modifications of the proteins were investigated by SDS-PAGE, mass spectrometry and size exclusion chromatography. According to our data, irradiation promoted structural modifications on both proteins, characterized by higher molecular weight forms (aggregates and oligomers). When analyzed by mass spectrometry, the irradiated bothropstoxin appeared in several oxidized forms. These results indicate that irradiation of toxic proteins can promote significant modifications in their structures, but still retain many of the original antigenic and immunological properties of native form.

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Journal of Psychedelic Studies
Authors:
Kevin J Byrne
,
Spencer Lindsay
,
Nicholas Baker
,
Christian Schmutz
, and
Ben Lewis

Abstract

Background and aims

Most modern modalities of psychedelic-assisted psychotherapy (PAP) aim to minimize harm and maximize support by utilizing close, formalized supervision for a single participant per session. However, these substances are used naturalistically in a wide variety of settings. Our goal was to evaluate the perceived benefits and harms of naturalistic psychedelic use in diverse settings, with and without guidance/supervision.

Methods

An anonymous survey was distributed over Internet forums to solicit responses from English-speaking adults, with questions regarding the setting and perceived mental health-related outcomes of classic psychedelics. Data were analyzed to compare effects of group versus solo setting on perceived outcomes.

Results

For the goal of improving mental health, use in a solo setting was more common than in a group setting (COR 0.37 (0.20–0.68), p = 0.03) and was associated with more subjective symptom improvement (COR 0.22 (0.11–0.42), p = 0.0002). However, there was no significant difference in perceived overall mental health benefit between use in group and solo settings (p = 1). Subjective negative outcomes on mental health were rare and not associated more so with psychedelic use in any particular setting. A majority of naturalistic psychedelic use took place in an informal setting, with no significant difference between solo or group users (95% vs 91%, p = 0.3).

Conclusions

Naturalistic psychedelic users are as likely to report an overall positive outcome and no more likely to report adverse events in group settings than in solo settings. This supports further research into PAP in group settings.

Open access
Journal of Radioanalytical and Nuclear Chemistry
Authors:
J. Baptista
,
D. Vieira
,
A. Galisteo Júnior
,
O. Higa
,
M. Casare
,
C. Yonamine
,
P. Caproni
,
L. Campos
,
H. de Andrade Júnior
,
P. Spencer
, and
N. Nascimento

Abstract  

In this work, the authors investigated the immunological behavior of bothropstoxin-I (BTHX-1), before and after irradiation process, and also the influence of scavengers substances on protein alterations induced by free radical production. Structural modifications were investigated by SDS-PAGE in reducing or non-reducing conditions. In vitro cytotoxicity assay was performed to test average toxic activities of BTHX-I. BALB/c Isogenic mice were immunized with irradiated or non-irradiated (native) forms of BTHX-I and antibody titers and isotypes were determined by ELISA method. Expression of murine cytokines was analyzed by using expression data obtained by quantitative real-time PCR (qPCR) assays. The results indicate that irradiation of proteins leads to significant structural modifications, and also changes the cytokines profile during immunization process, regarding a suitable approach to new immunogenic production.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
J. Baptista
,
D. Vieira
,
A. Galisteo-Júnior
,
P. Caproni
,
M. Casare
,
H. de Andrade-Júnior
,
P. Spencer
, and
N. Nascimento

Abstract  

We investigated the immunological behavior of BTHX-1, before and after irradiation. SDS-PAGE showed that BTHX-1 irradiated in the presence of NaNO3, had its structure preserved. Animals’ plasma immunized with native BTHX-1 had high IgG1 titers. The irradiated protein induced high titers of IgG2b. When the toxin was irradiated with t-butanol, there was a slight decrease in the production of IgG2b. Real-time PCR showed that both the IL-2 as for IL4 was more expression from the cells of the animals immunized with BTHX-1 irradiated. These results indicate that irradiation of proteins leads to significant structural modifications.

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