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Abstract
Carbon-13 and oxygen-18 isotope effects in the decarboxylation of nicotinic acid of natural isotopic composition above and below its melting temperature have been studied and compared with the primary (PKIE) and secondary kinetic isotope effects (SKIE) of13C and18O, respectively, in the decarboxylation of other heterocyclic acids. The temperature dependence of the secondary oxygen-18 isotope effects is negative in the total 221–255°C temperature interval investigated initially. The13C KIE measured above melting point of N.A. (temperature interval 235–270°C) are located in the range 1.007–1.009. Below melting point of nicotinic acid the13C KIE are larger and reveal the negative temperature dependence (13C KIE decreases with decreasing the reaction temperature from 1.013/at 230°C to 1.0114/at 221°C). A discussion of the above isotopic results is presented.
Abstract
Background and aims
The prominent cognitive-behavioral model of hoarding posits that information processing deficits contribute to hoarding disorder. Although individuals with hoarding symptoms consistently self-report attentional and impulsivity difficulties, neuropsychological tests have inconsistently identified impairments. These mixed findings may be the result of using different neuropsychological tests, tests with poor psychometric properties, and/or testing individuals in a context that drastically differs from their own homes.
Methods
One hundred twenty-three participants (hoarding = 63; control = 60) completed neuropsychological tests of sustained attention, focused attention, and response inhibition in cluttered and tidy environments in a counterbalanced order.
Results
Hoarding participants demonstrated poorer sustained attention and response inhibition than the control group (CPT-3 Omission and VST scores) and poorer response inhibition in the cluttered environment than when in the tidy environment (VST scores). CPT-3 Detectability and Commission scores also indicated that hoarding participants had greater difficulty sustaining attention and inhibiting responses than the control group; however, these effect sizes were just below the lowest practically meaningful magnitude. Posthoc exploratory analyses demonstrated that fewer than one-third of hoarding participants demonstrated sustained attention and response inhibition difficulties and that these participants reported greater hoarding severity and greater distress in the cluttered room.
Discussion and conclusions
Given these findings and other studies showing that attentional difficulties may be a transdiagnostic factor for psychopathology, future studies will want to explore whether greater sustained attention and response inhibition difficulties in real life contexts contribute to comorbidity and functional impairment in hoarding disorder.
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.
Abstract
Recent research suggests that men may possess adaptations that evolved to counter strategic variation in women's preferences for masculine men. For example, women's preferences for masculine, dominant men are stronger during the fertile phase of the menstrual cycle than at other times and men demonstrate increased sensitivity to facial cues of male dominance when their partners are ovulating. Such variation in men's dominance perceptions may promote efficient allocation of men's mate guarding effort (i.e., allocate more mate guarding effort in response to masculine, dominant men in situations where women show particularly strong preferences for such men). Here, we tested for further evidence of adaptations that may have evolved to counter strategic variation in women's masculinity preferences. Men who reported having particularly feminine romantic partners demonstrated a greater tendency to attribute dominance to masculinized male faces than did men who reported having relatively masculine romantic partners. This relationship between partner femininity and men's sensitivity to facial cues of male dominance remained significant when we controlled for potential confounds (men's age, self-rated masculinity, reported commitment to their relationship, and the length of the relationship) and may be adaptive given that feminine women demonstrate particularly strong preferences for masculine, dominant men. While previous research has emphasized variation in women's masculinity preferences, our findings add to a growing body of research suggesting that sexual selection may also have shaped adaptations that evolved to counter such systematic variation in women's preferences for masculine, dominant men.
Abstract
Background and aims
Problem gambling severity and gambling-related harm are closely coupled, but conceptually distinct, constructs. The primary aim was to compare low-risk gambling limits when gambling-related harm was defined using the negative consequence items of the Problem Gambling Severity Index (PGSI-Harm) and the Short Gambling Harms Scale items (SGHS-Harm). A secondary aim was compare low-risk limits derived using a definition of harm in which at least two harms across different domains (e.g. financial and relationship) were endorsed with a definition of harm in which at least two harms from any domain were endorsed.
Methods
Data were collected from dual-frame computer-assisted telephone interviews of 5,000 respondents in the fourth Social and Economic Impact Study (SEIS) of Gambling in Tasmania. Receiver operating characteristic (ROC) curve analyse were conducted to identify low-risk gambling limits.
Results
PGSI-Harm and SGHS-Harm definitions produced similar overall limits: 30–37 times per year; AUD$510–$544 per year; expenditure comprising no more than 10.2–10.3% of gross personal income; 400–454 minutes per year; and 2 types of gambling activities per year. Acceptable limits (AUC ≥0.70) were identified for horse/dog racing, keno, and sports/other betting using the PGSI definition; and electronic gaming machines, keno, and bingo using the SGHS definition. The requirement that gamblers endorse two or more harms across different domains had a relatively negligible effect.
Discussion and conclusions
Although replications using alternative measures of harm are required, previous PGSI-based limits appear to be robust thresholds that have considerable potential utility in the prevention of gambling-related harm.
Carbon isotope effect studies in the mechanism of reactions of alkynes with formic acid
II.13C fractionation in the decarbonylation of Merck formic acid in the presence of phenylacetylene
Abstract
The13C fractionation has been studied in the reaction of phenylacetylene with the excess of liquid Merck formic acid at 30 and 40 °C to see the contribution of the13C fractionation in the formolysis of transient 
-formoxystyrene to the experimentally observed global13C fractionation. The13C fractionation has been investigated also in the hydration of 1 ml of PhC
CH with 1 ml of formic acid in the temperature interval of 80–100°C. The13C KIE equal to 1.0168 at 91.75 °C and 1.0167 at 100°C indicate that the self-decomposition of formic acid in such experimental conditions is already largely suppressed. The isotope effect is discussed within the framework of the sequence of reaction steps leading to acetophenone and carbon monoxide production listed in part I.
Abstract
We report here a search for the “live” 244Pu in 1 kg deep-sea dry sediment collected in 1992 in the North Pacific. After a 546 day alpha-counting of a Pu fraction chemically separated from the alkaline-fused sediment sample at Kanazawa University, AMS analysis was performed at Hebrew University and Weizmann Institute. Only one count of 244Pu with no background ions was detected, indicating no excess over the expected stratospheric man-made fallout. A limit of 0.2 atoms of 244Pu cm−2·y−1 for extra terrestrial deposition was set under reasonable assumptions and it was then concluded from this result and the available data on interstellar medium (ISM) that the abundance of 244Pu in the ISM is less than 2·10−11 g 244Pu (g·ISM)−1. Implications of the present result are discussed.
Abstract
Crystal structure (polymorphism) as well as crystal shape (morphology) and size have a huge practical and commercial impact on active substances all the way from research to manufacture of the final product. For an optimal development process, it is important to have an integrated approach to these issues ranging from a systematic polymorphism screening to a controlled scale-up of the crystallization process. The polymorphism program has to be tailored according to the development stage. Particularly suitable for an early development stage is a high-throughput polymorphism screening, which is the basis for a more thorough investigation if the product proceeds further in development. Such a comprehensive polymorphism investigation involves further crystallization experiments and extensive physicochemical characterization of the various forms. In this article the high-throughput polymorphism screening method that we have developed is described. Using carbamazepine as an example, the power of this high-throughput polymorphism screening system is demonstrated. Not only were all published forms found, but also new forms were identified. In the second part of the article, important considerations for crystallization optimization are discussed, again using the example of carbamazepine.
Abstract
Background and aims
It is well understood that engagement with some forms of gambling, like EGMs, is riskier than other forms. However, while reports of associations are common, few studies have attempted to evaluate and compare the relative risk of all available forms, and none have estimated the relative contribution of each form to the total burden of gambling problems (GP) in a population.
Methods
Using an aggregated dataset of national and state-based prevalence studies in Australia (N = 71,103), we estimated prevalence and unique effects of frequency of engagement on each form on GP. Two alternative numerical methods were then applied to infer the relative contribution of each form to the total amount of GP.
Results
EGMs are responsible for 51%–57% of gambling problems in Australia, and 90% of gambling problems are attributable to EGMs, casino, race, and sports betting. Casino table games and EGMs are equally risky at the individual level, but the former contribute far less to problems due to low participation. Bingo and lottery play show no statistically detectable risk for GP.
Discussion and conclusion
The results illustrate which forms present the greatest population burden and illuminate the reasons why. EGMs have an outsized impact. EGM uniquely combines high risk conditional on play, with a high participation rate and a high frequency of play among participants. This is in contrast to risky but less commonly played casino games, and prevalent but non-risky forms like lotteries. We conclude that EGM regulation should be a primary focus of policy action in Australia. More innovative policy ideas relating to EGMs should be tested due to the disproportionate impact of this product type.
