Hormonal regulation of wheat growth during hydroponic culture

Hormonal control of root growth has been explored as one means to alleviate the crowding of plant root systems experienced in prototype hydroponic biomass production chambers being developed by the CELSS Breadboard Project. Four plant hormones, or their chemical analogs, which have been reported to selectively inhibit root growth, were tested by adding them to the nutrient solutions on day 10 of a 25 day growth test using spring wheat in hydroponic cultures. Growth and morphological changes is both shoot and root systems were evaluated. In no case was it possible to inhibit root growth without a comparable inhibition of shoot growth. It was concluded that this approach is unlikely to prove useful for wheat

Imagined futures: young men's talk about fatherhood and domestic life

As part of an extensive series of interviews about men and masculinity, small groups of 17 to 18-year-old male students were invited to look forward to their future romantic and domestic lives. Their responses were analysed using the approach and methods of discourse analysis in order to examine both the interpretative resources used within their accounts and to look at how the young men attempted to manage the ‘ideological dilemma’ (Billig, Condor, Edwards, Gane, Middleton & Radley, 1988) that was framed by these cultural themes. The analysis describes three such strategies while paying particular attention to the ‘action orientation’(Heritage, 1984) of these constructions. Finally, the paper moves on to discuss, albeit briefly, the broader implications of this research

The multitasking framework: the effects of increasing workload on acute psychobiological stress reactivity

A variety of techniques exist for eliciting acute psychological stress in the laboratory; however, they vary in terms of their ease of use, reliability to elicit consistent responses and the extent to which they represent the stressors encountered in everyday life. There is, therefore, a need to develop simple laboratory techniques that reliably elicit psychobiological stress reactivity that are representative of the types of stressors encountered in everyday life. The multitasking framework is a performance-based, cognitively demanding stressor, representative of environments where individuals are required to attend and respond to several different stimuli simultaneously with varying levels of workload. Psychological (mood and perceived workload) and physiological (heart rate and blood pressure) stress reactivity was observed in response to a 15-min period of multitasking at different levels of workload intensity in a sample of 20 healthy participants. Multitasking stress elicited increases in heart rate and blood pressure, and increased workload intensity elicited dose–response increases in levels of perceived workload and mood. As individuals rarely attend to single tasks in real life, the multitasking framework provides an alternative technique for modelling acute stress and workload in the laboratory

Negotiating hegemonic masculinity: imaginary positions and psycho-discursive practices

In this paper we provide a critical analysis of the concept of hegemonic masculinity. We argue that although this concept embodies important theoretical insights, it is insufficiently developed as it stands to enable us to understand how men position themselves as gendered beings. In particular it offers a vague and imprecise account of the social psychological reproduction of male identities. We outline an alternative critical discursive psychology of masculinity. Drawing on data from interviews with a sample of men from a range of ages and from diverse occupational backgrounds, we delineate three distinctive, yet related, procedures or psycho-discursive practices, through which men construct themselves as masculine. The political implications of these discursive practices, as well as the broader implications of treating the psychological process of identification as form of discursive accomplishment, are also discussed

Covering collections and a challenge problem of Serre

We answer a challenge of Serre by showing that every rational point on the projective curve X$^4$ + Y$^4$ = 17 Z$^4$ is of the form ($\pm$1, $\pm$2, 1) or ($\pm$2, $\pm$1, 1). Our approach builds on recent ideas from both Nils Bruin and the authors on the application of covering collections and Chabauty arguments to curves of high rank. This is the only value of c$\le$81 for which the Fermat quartic X$^4$ + Y$^4$ = c Z$^4$ cannot be solved trivially, either by local considerations or maps to elliptic curves of rank 0, and it seems likely that our approach should give a method of attack for other nontrivial values of c

Barriers to cervical screening participation in high-risk women

Aim Women aged 25–35 years, for whom cervical cancer is most problematic, are least likely to participate in the cervical screening programme. Therefore, identifying barriers to screening participation in this high-risk group is essential. Subject and methods A sample of 430 women completed an electronic survey of their cervical screening history and answered questions on sociodemographic, behavioural, attitudinal and informational barriers to cervical screening uptake. Logistic regression was used to predict cervical screening non attendance. Results Women with more than 10 sexual partners in their lifetime were more likely, but women from ethnic minorities, less likely to participate in the cervical screening programme. Women unaware of the recommended screening interval were also less likely to be screened, as were women who believed that screening is a test for cancer. Screening was also less likely among women who endorsed the belief that screening in the absence of symptoms is unnecessary. Conclusion These data highlight poor knowledge of the recommended screening interval and purpose of cervical cancer screening in this high-risk group. As such, interventions that target these informational barriers might be most effective for increasing cervical screening uptake in this high-risk group

Finding rational points on bielliptic genus 2 curves

We discuss a technique for trying to find all rational points on curves of the form $Y^2 = f_3 X^6 + f_2 X^4 + f_1 X^2 + f_0$, where the sextic has nonzero discriminant. This is a bielliptic curve of genus 2. When the rank of the Jacobian is 0 or 1, Chabauty's Theorem may be applied. However, we shall concentrate on the situation when the rank is at least 2. In this case, we shall derive an associated family of elliptic curves, defined over a number field Q(a). If each of these elliptic curves has rank less than the degree of Q(a) : Q, then we shall describe a Chabauty-like technique which may be applied to try to find all the points (x,y) defined over Q(a) on the elliptic curves, for which x is in Q. This in turn allows us to find all Q-rational points on the original genus 2 curve. We apply this to give a solution to a problem of Diophantus (where the sextic in X is irreducible over Q), which simplifies the recent solution of Wetherell. We also present two examples where the sextic in X is reducible over Q

Narrative in adolescent specific language impairment (SLI): a comparison with peers across two different narrative genres

Background: Narrative may provide a useful way in which to assess the language ability of adolescents with specific language impairment and may be more ecologically valid than standardized tests. However, the language of this age group is seldom studied and, furthermore, the effect of narrative genre has not been explored in detail. Methods & Procedures: A total of 99 typically developing adolescents and 19 peers with specific language impairment were given two different types of narrative task: a story-telling condition and a conversational condition. Four areas of narrative (productivity, syntactic complexity, syntactic errors and performance) were assessed. Outcomes & Results: The group with specific language impairment was poorer on most aspects of narrative confirming recent research that specific language impairment is a long-term disorder. A number of measures also showed interactions between group and genre, with story-telling proving to be a disproportionately more difficult task for the specific language impairment group. Error analysis also suggested that the specific language impairment group was making qualitatively different errors to the typically developing group, even within a genre. Conclusions: Adolescents with specific language impairment are not only poorer at both types of narrative than peers, but also show different patterns of competence and error, and require more support from the narrative-partner. Clinical Implications: Assessments of adolescents are less frequent than at younger ages. This is partly because of the sparsity of tests available in this age range. Qualitative analysis of narrative might prove a useful alternative. The findings suggest that in every-day conversation, young people with specific language impairment manage their difficulties more discreetly and this might make them harder to identify in a mainstream setting

Does Student Success Skills have an impact on school connectedness and self-regulation of inner-city, African-American elementary students?

Brief overview of the article, Connectedness and Self-Regulation as Constructs of the Student Success Skills Program in Inner-City African American Elementary School Students, originally published in the Journal of Counseling & Development. The authors include a summary of the key components of the original study, including the introduction, method, and results sections of the paper. In addition, they offer a critical perspective speaking to the limitations of the study and a section addressing implications for practice like the effects of school counseling interventions on academic achievement indicators

Photoproduction of K^+ Mesons in Hydrogen

The photoproduction of K^+ mesons in hydrogen has been measured with the purpose of extending the previous CalTech measurements to smaller angles, and obtaining better absolute values for the cross sections. The technique of Donoho and Walker, using a magnetic spectrometer and a time-of-flight measurement to detect the K^+ mesons, was modified so as to achieve a better discrimination against pions and scattered protons. The results obtained are in fairly good agreement with the more extensive measurements made at Cornell by a somewhat different method