Search Results

You are looking at 31 - 39 of 39 items for

  • Author or Editor: J. Smith x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract  

Ion chromatography (IC) can be used to separate radioiodine from fission products and other ionic species in complex reprocessing solution matrices. A preliminary concentration and separation of the radioiodine is performed using a column filled with a platinum-coated copper bed which converts all forms of iodine to iodide and selectively adsorbs the iodide. The separation is completed by employing an anion chromatographic system. The iodide peak aliquot is collected for subsequent radioanalysis by low energy photon spectroscopy. Results indicate quantitative separation and recovery of iodine. The entire system is automated under computer control and is able to handle small (l) and large (500 ml) sample sizes.

Restricted access
Journal of Behavioral Addictions
Authors:
Tyler B. Kruger
,
Mike J. Dixon
,
Candice Graydon
,
Madison Stange
,
Chanel J. Larche
,
Stephen D. Smith
, and
Daniel Smilek

Abstract

Background and aims: Slot machines are a pervasive form of gambling in North America. Some gamblers describe entering “the slot machine zone”—a complete immersion into slots play to the exclusion of all else. Methods: We assessed 111 gamblers for mindfulness (using the Mindful Attention Awareness Scale (MAAS)), gambling problems (using the Problem Gambling Severity Index (PGSI)), depressive symptoms (using the Depression, Anxiety, and Stress Scale), and boredom proneness (using the Boredom Proneness Scale). In a counterbalanced order, participants played a slot machine simulator and completed an auditory vigilance task. During each task, participants were interrupted with thought probes to assess whether they were: on-task, spontaneously mind-wandering, or deliberately mind-wandering. After completing each task, we retrospectively assessed flow and affect. Compared to the more exciting slots play, we propose that gamblers may use deliberate mind-wandering as a maladaptive means to regulate affect during a repetitive vigilance task. Results: Our key results were that gamblers reported greater negative affect following the vigilance task (when compared to slots) and greater positive affect following slots play (when compared to the vigilance task). We also found that those who scored higher in problem gambling were more likely to use deliberate mind-wandering as a means to cope with negative affect during the vigilance task. Using hierarchical multiple regression, we found that the number of “deliberately mind-wandering” responses accounted for unique variance when predicting problem gambling severity (over and above depression, mindfulness, and boredom proneness). Conclusions: These assessments highlight a potential coping mechanism used by problem gamblers in order to deal with negative affect.

Open access

Summary  

Heat and CO2rates are measured on M. domesticapupae as a function of age and temperature. Heats of combustion of flies, pupae, and puparia are also measured. Heat and CO2rates decrease for 3 d post-pupation and increase exponentially over 4 d prior to eclosure. Heat and CO2rates are low and increase slowly from 5 to 23C, then rapidly increase from 23 to 26C, then more slowly up to 38C where pupae are stressed. Respiratory substrate varies with age and temperature, is a mix of lipids and carbohydrates, and has an average carbon oxidation state of -0.3 at room temperature. Humidity, elevated CO2, or reduced O2did not affect pupal metabolism.

Restricted access
Journal of Flow Chemistry
Authors:
Sarah E. Smith
,
Zachary J. Huba
,
Fahad Almalki
,
J. R. Regalbuto
,
John Monnier
, and
Everett E. Carpenter

Magnetic nanomaterials have many applications in the fields of catalysis, medicine, and environmental studies. An emerging synthetic method capable of large-scale production of nanomaterials is a continuous-flow microreactor. However, translating known conventional benchtop reactions to a continuous-flow system can be difficult; reaction parameters such as reaction time and viscosity of the solution are significant limitations in flow-based systems. In this study, nanocrystalline Cu—Ni and Cu—Co core—shell materials were successfully synthesized using a capillary microreactor in a one-step process. Ethanol was used as solvent, allowing for faster reaction times and reduced reaction solution viscosity, compared to similar bench top synthetic protocols. Both nanocomposites were tested for activity in Fischer—Tropsch and showed activity above 220 °C. This study shows that a continuous-flow capillary microreactor has the capabilities to make complex metallic nanomaterials at short reaction times with proper selection of reaction solvent systems.

Restricted access
Journal of Behavioral Addictions
Authors:
Mike J. Dixon
,
Jeffrey Gutierrez
,
Chanel J. Larche
,
Madison Stange
,
Candice Graydon
,
Tyler B. Kruger
, and
Stephen D. Smith

Background and aims

Slot machines are a very popular form of gambling. In this study, we look at two different routes to enjoying slots play. One route involves the degree to which players react to rewards. The other route involves what we call dark flow – a pleasurable, but maladaptive state where players become completely engrossed in slots play, providing an escape from the depressing thoughts that characterize their everyday lives.

Methods

One hundred and twenty-nine high-frequency slots players were tested on slot-machine simulators set up in the lobby of a casino. We measured reward reactivity using post-reinforcement pauses (PRPs) and the force with which players pressed the spin button following different slot-machine outcomes. For each player, we calculated the slopes of PRPs and force as a function of credit gains. We also assessed players’ slots game enjoyment and their experience of dark flow, depression, and problem gambling.

Results

Both the PRP and the force measures of reward reactivity were significantly correlated with players’ enjoyment of the slots session, but neither measure was correlated with either problem gambling or depression. Ratings of dark flow were strongly correlated with slots enjoyment (which accounted for far more positive affect variance than the reward reactivity measures) and were correlated with both problem gambling scores and depression.

Discussion and conclusions

Our results suggest that of these two routes to enjoying slot-machine play, the dark flow route is especially problematic. We contend that the dark flow state may be enjoyable because it provides escape from the negative thoughts linked to depression.

Open access
Cereal Research Communications
Authors:
B.L. Béres
,
N.Z. Lupwayi
,
F.J. Larney
,
B. Ellert
,
E.G. Smith
,
T.K. Turkington
,
D. Pageau
,
K. Semagn
, and
Z. Wang

Research indicates that not all crops respond similarly to cropping diversity and the response of triticale (× Triticosecale ssp.) has not been documented. We investigated the effects of rotational diversity on cereals in cropping sequences with canola (Brassica napus L.), field pea (Pisum sativum L.), or an intercrop (triticale:field pea). Six crop rotations were established consisting of two, 2-yr low diversity rotations (LDR) (continuous triticale (T-T_LDR) and triticale-wheat (Triticum aestivum L.) (T-W_LDR)); three, 2-yr moderate diversity rotations (MDR) (triticale-field pea (T-P_MDR), triticale-canola (T-C_MDR), and a triticale: field pea intercrop (T- in P_MDR)); and one, 3-yr high diversity rotation (HDR) (canola-triticale-field pea (C-T-P_HDR)). The study was established in Lethbridge, Alberta (irrigated and rainfed); Swift Current (rainfed) and Canora (rainfed), Saskatchewan, Canada; and carried out from 2008 to 2014. Triticale grain yield for the 3-yr HDR was superior over the LDR rotations and the MDR triticale-field pea system; however, results were similar for triticale-canola, and removal of canola from the system caused a yield drag in triticale. Triticale biomass was superior for the 3-yr HDR. Moreover, along with improved triticale grain yield, the 3-yr HDR provided greater yield stability across environments. High rotational diversity (C-T-P_HDR) resulted in the highest soil microbial community and soil carbon concentration, whereas continuous triticale provided the lowest. Net economic returns were also superior for C-T-P_HDR ($670 ha–1) and the lowest for T-W_LDR ($458 ha–1). Overall, triticale responded positively to increased rotational diversity and displayed greater stability with the inclusion of field pea, leading to improved profitability and sustainability of the system.

Restricted access

Abstract

Women demonstrate stronger preferences for femininity when assessing men's attractiveness for long-term rather than short-term relationships. One explanation of this effect is that the pro-social traits associated with femininity are particularly important for long-term relationships. This explanation has recently been challenged, however, following null findings for effects of pro-social attributions on women's preferences for feminine long-term partners. A limitation of these latter analyses is that they did not consider hormonal contraceptive use, which is a factor that previous studies suggest affects mate preferences. In our study, we found that women not using hormonal contraceptives demonstrated stronger preferences for femininity in men's faces when assessing men as long-term partners than when assessing men as short-term partners. Moreover, this effect was most pronounced among women who perceived feminine men as particularly trustworthy. No equivalent effects were observed among women using hormonal contraceptives. These findings support the proposal that the effect of relationship context on women's face preferences occurs, at least in part, because women value pro-social traits more in long-term than short-term partners. Additionally, our findings suggest that both hormonal contraceptive use and individual differences in perceptions of pro-social traits modulate the effect of relationship context on women's face preferences.

Restricted access
Journal of Evolutionary Psychology
Authors:
Paul J. Fraccaro
,
Benedict C. Jones
,
Jovana Vukovic
,
Finlay G. Smith
,
Christopher D. Watkins
,
David R. Feinberg
,
Anthony C. Little
, and
Lisa M. Debruine

Abstract

Although humans can raise and lower their voice pitch, it is not known whether such alterations can function to increase the likelihood of attracting preferred mates. Because men find higher-pitched women's voices more attractive, the voice pitch with which women speak to men may depend on the strength of their attraction to those men. Here, we measured voice pitch when women left voicemail messages for masculinized and feminized versions of a prototypical male face. We found that the difference in women's voice pitch between these two conditions positively correlated with the strength of their preference for masculinized versus feminized male faces, whereby women tended to speak with a higher voice pitch to the type of face they found more attractive (masculine or feminine). Speaking with a higher voice pitch when talking to the type of man they find most attractive may function to reduce the amount of mating effort that women expend in order to attract and retain preferred mates.

Restricted access
Journal of Radioanalytical and Nuclear Chemistry
Authors:
M. Douglas
,
J. Friese
,
L. Greenwood
,
O. Farmer
,
M. Thomas
,
T. Maiti
,
E. Finn
,
S. Garofoli
,
P. Gassman
,
M. Huff
,
S. Schulte
,
S. Smith
,
K. Thomas
, and
P. Bachelor

Abstract  

Quantitative measurement of fission and activation products resulting from neutron irradiation of fissile materials is of interest for applications in environmental monitoring, nuclear waste management, and national security. Based on established separation processes involving co-precipitation, solvent extraction, and ion-exchange and extraction chromatography, we have optimized a proposed sequence of separation steps to allow for the timely quantification of analytes of interest. We have recently evaluated this scheme using an irradiated sample to examine the adequacy of separations for measurement of desired analytes by gamma spectrometry. Here we present the radiochemical separations utilized and the yields and purity obtained.

Restricted access