The relationship between phase and period responses to light pulses

Current theories of stable circadian entrainment postulate phase delays should be associated with period lengthening, while phase advances should be associated with period shortening. While characterising features of the rat PRC to light, we noted substantial numbers of responses that displayed the opposite pattern. Forty-eight rats provided data for 192 phase responses. Limiting our analysis to phase shifts greater than 1 hour, we found 44 displayed the expected predicted relationship, and 33 displayed the contrary paradoxical relationship. Paradoxical responders possessed significantly shorter initial activity periods, compared to predicted responders. Activity was significantly lengthened by paradoxical responders and shortened by predicted responders following light pulse exposure. These results suggest a second mode of stable entrainment. Additionally, these results indicate entrainment mode, predicted or paradoxical, is based upon activity period duration. Short activity period durations will be associated with paradoxical responses, long durations will be associated with predicted responses. We argue that, given the dynamic changes in photoperiod, both modes of entrainment are necessary to provide stable entrainment across the year.

The architectural edifice and the phantoms of history

Starting with the literal and physical role of the "ground," this article attempts to bring this "ground" into a discursive arena. In particular, the author is thinking about the period at the end of a war, the period in between destruction and reconstruction, exemplified in some classic postwar films in which the architecture of the city is in a state of ruin—deformed, eroded, and dark—but there is no further destruction. The article calls this period "a gap of history" and its investigation is set against a claim that architecture is a reconstructive practice, that it is enlightening and aspiring. History, on the other hand, is captured by scenes of the battlefield and dominated by a narrative of war and destruction. The article makes reference to the real and fantasy desire for destruction (war and history) and reconstruction (architecture), and how through the connecting plane of the ground architecture is entangled in war and history of destruction as it figures in reconstruction. Architecture is contingent on history as discursive—history that is not unified, fixed, or evolutionary but rather contested and rewritten within a conflictual battlefield.

Media/ting change: the print media's role in mediating education policy in a period of radical reform in Victoria, Australia

This paper draws upon critical discourse analysis, cultural studies and communication theory, studies on media and educational reform, and the work of Bernstein, Bourdieu and Luhmann in particular, to explore how the print and media 'mediated' a period of educational change marked by moves to self-management in schools in Victoria, Australia. It considers how the media was mobilized by various education stakeholders, and in turn informed relations between schools and government, through policy discourses and texts. It considers why and how particular themes became media 'issues', how schools and teachers responded to these issues, and how the media was used by various stakeholders in education to shape policy debates. It is based on a year-long qualitative study that explored critical incidents and representations about education in the print media over a year in the daily press. It illustrates the ways in which a neo-liberal Victorian government mobilized the media to gain strategic advantage to promote radical education reform policies, considers the media effects of this media/tion process on schools and teachers, and conceptualizes how school and system performance is fed from and into media representations, public perceptions and community understandings of schools and teachers' work.

On the extent of speculative activity in the Indian stock market during badla and post-badla period

The authors test the existence of speculative activity in the Indian stock market during badla and post-badla period. They further investigate whether speculative activity migrated to single stocks futures market after banning of badla system. In both the tests it is found that there is no evidence of strong speculative activity in the Indian market. The research raises some questions on the regulators decision of banning badla system and sheds some light on the future decisions with respect to single stock futures market.

The haemodynamic status of cardiac surgical patients in the initial 2-h recovery period

Background
Critical care nurses caring for cardiac patients in the immediate postoperative period continually make decisions about the implications and treatment of their patients' haemodynamic status.

Aim
The aim of this study was to describe the haemodynamic status of patients on admission to critical care and over the 2-h period following cardiac surgery.

Methods
A quantitative, descriptive design was used. Data were collected using non-participant observation and an observation tool. The sample consisted of 38 patients.

Results
Analysis of data revealed the dynamic nature of the haemodynamic status of postoperative cardiac patients. On admission, 60% of patients (n = 23) were haemodynamically unstable. The instability in these patients (n = 23) was due to hypotension (34%), bleeding (21%) and hypoxaemia (18%). During the 2-h recovery period, 55% of patients were hypotensive, 16% of patients had low cardiac output syndrome and 16% of patients had low systemic vascular resistance (SVR) syndrome. Twenty-one percent of patients experienced bleeding complications. Shivering was a clinically significant problem in terms of occurrence (23%) and duration (X = 45, S.D. = 30 min). Twenty-nine percent of patients (n = 11) had a profound deterioration in haemodynamic status, necessitating urgent interventions.

Conclusion
Haemodynamic parameters indicate that 95% of patients in this study were haemodynamically unstable at some time during the initial 2-h recovery period. These findings inform resourcing decisions by organisations and have implications for nurses' assessment and interventional haemodynamic decision making.

The effect of repeated pulses of light at the same time on period responses of the rat circadian pacemaker.

A consequence of simple velocity-based models is that, in response to light pulses, the circadian period should adjust inversely to phase. In addition, because of the interaction of circadian period and phase response, earlier circadian period changes should modify later circadian period changes. The literature contains few mentions of response curves of circadian period responses following light pulses. Rats were exposed to four pulses of light (60 minutes, 1000 lux) at the same circadian time, a minimum of 26 days apart; we assessed period responses and possible bias in the period-response curve. Modulation of circadian period following light-induced phase responses was examined by assessing the period of running wheel activity onset. Phase and circadian period were not consistently found to share an inverse relationship. Moreover, biases in initial period tended to be increased by the experimental protocol regardless of circadian time of pulse. Rats with a short initial (highvelocity) period had a lengthened period, while rats with a long initial period (low velocity) tended to have a reduce period. However, rats with a long initial period were phase delay biased, not phase advance biased. These results do not support a simple velocity model of the pacemaker.

The early postnatal period : exploring women's views, expectations and experiences of care using focus groups in Victoria, Australia

Background: There is growing evidence from Australia and overseas that the care provided in hospital in the early postnatal period is less than ideal for both women and care providers. Many health services face increasing pressure on hospital beds and have limited physical space available to care for mothers and their babies. We aimed to gain a more in-depth understanding of women's views, expectations and experiences of early postnatal care.

Methods: We conducted focus groups in rural and metropolitan Victoria, Australia in 2006. Fifty-two people participated in eight focus groups and four interviews. Participants included eight pregnant women, of whom seven were pregnant with their first baby; 42 women who were in the postpartum period (some up to twelve months after the birth of their baby); and two partners. All participants were fluent in English. Focus group guides were developed specifically for the study and explored participants' experiences and/or expectations of early postnatal care in hospital and at home, with an emphasis on length of hospital stay, professional and social support, continuity of care, and rest. Discussions were audio-taped and transcribed verbatim. A thematic network was constructed to describe and connect categories with emerging basic, organizing, and global themes.

Results: Global themes that emerged were: anxiety and/or fear; and the transition to motherhood and parenting. The needs of first time mothers were considered to be different to the needs of women who had already experienced motherhood. The women in this study were generally concerned about the safety of their new baby, and lacked confidence in themselves as new mothers regarding their ability to care for their baby. There was a consistent view that the physical presence and availability of professional support helped alleviate these concerns, and this was especially the case for women having a first baby.

Conclusion: Women have anxieties and fears around early parenting and their changing role, and may consider that the physical availability of professional care providers will help during this time. Care providers should be cognisant of these potential issues. It is crucial that women's concerns and needs be considered when service delivery changes are planned. If anxiety around new parenting is a predominant view then care providers need to recognise this and ensure care is individualised to address each woman's/families particular concerns.

Changes in quality of life and coping among people with multiple sclerosis over a 2 year period

There is a need to investigate the impact of different coping strategies on quality of life (QOL) of people with multiple sclerosis (MS), in order to better inform intervention programs for this population. This study evaluated the relationship between QOL and coping over a 2 year period among people with MS. Participants were 382 people with MS (144 male, 238 females) and 291 people without a neurological or other chronic illness from the general population (101 males, 190 females). People with MS experienced lower QOL than the control group in the domains of global QOL, independence, social and spiritual QOL scales, as well as the problem solving and social/emotional support coping scales. Interestingly, people with MS experienced higher psychological QOL than the general population, and higher detachment and focusing on the positive coping. Over time, people with MS demonstrated increases in their global QOL as well as in their social/emotional support coping. Women demonstrated higher levels than men of global QOL and Social/emotional support coping. The results of these findings have implications for information and intervention programs for people with MS.

Longitudinal studies into science learning - methodological issues

The Gold Standard for education research promotes randomized controlled trials (RCTs) that can produce generalizable knowledge claims across similar problems and situations. Unfortunately, the Gold Standard does not fully recognize the need for developmental research to better understand the problem space, formulate theory and approaches to teaching and learning, and formulate and pursue associated research questions. This developmental research has been a precursor to the development of interventions together with the necessary instrumentation and technologies required to fully investigate these through the more formal evaluative processes imagined by the Gold Standard. This chapter focuses on longitudinal studies that cover a continuum from such developmental research to research that uses control-experimental features to evaluate interventions. These studies attend to a set of issues dealing with  developmental progressions and learning trajectories that require  investigation over an extended period of time. It will be argued that
these longitudinal studies of a variety of methodological types represent quality research in that rigorous design and implementation produce  evidence-based claims. The chapter examines the nature of the relationship between evidence and claims in these studies, to show the possibility of building in control features every bit as strong as those in classic Gold Standard designs. Further, it will be argued that, given the complexity of learning pathways, a simplistic interpretation of RCTs conducted over the shorter term can be misleading in terms of both internal and external validity claims.

Effects of dietary astaxanthin concentration and feeding period on the skin pigmentation of Australian snapper Pagrus auratus (Bloch & Schneider, 1801)

A single-factor experiment was conducted to investigate the effects of dietary astaxanthin concentration on the skin colour of snapper. Snapper (mean weight=129 g) were held in white cages and fed one of seven dietary levels of unesterified astaxanthin (0, 13, 26, 39, 52, 65 or 78 mg astaxanthin kg⁻¹) for 63 days. Treatments comprised four replicate cages, each containing five fish. The skin colour of all fish was quantified using the CIE L^*, a^*, b^* colour scale after 21, 42 and 63 days. In addition, total carotenoid concentrations of the skin of two fish cage−1 were determined after 63 days. Supplementing diets with astaxanthin strongly affected redness (a^*) and yellowness (b^*) values of the skin at all sampling times. After 21 days, the a^* values increased linearly as the dietary astaxanthin concentration was increased before a plateau was attained between 39 and 78 mg kg⁻¹. The b^* values similarly increased above basal levels in all astaxanthin diets. By 42 days, a^* and b^* values increased in magnitude while a plateau remained between 39 and 78 mg kg⁻¹. After 63 days, there were no further increases in measured colour values, suggesting that maximum pigmentation was imparted in the skin of snapper fed diets >39 mg kg⁻¹ after 42 days. Similarly, there were no differences in total carotenoid concentrations of the skin of snapper fed diets >39 mg kg⁻¹ after 63 days. The plateaus that occurred in a^* and b^* values, while still increasing in magnitude between 21 and 42 days, indicate that the rate of astaxanthin deposition in snapper is limited and astaxanthin in diets containing >39 mg astaxanthin kg⁻¹ is not efficiently utilized. Astaxanthin retention after 63 days was greatest from the 13 mg kg⁻¹ diet; however, skin pigmentation was not adequate. An astaxanthin concentration of 39 mg kg⁻¹ provided the second greatest retention in the skin while obtaining maximum pigmentation. To efficiently maximize skin pigmentation, snapper growers should commence feeding diets containing a minimum of 39 mg unesterified astaxanthin kg⁻¹ at least 42 days before sale.