Osmoregulation in elephant fish Callorhinchus Milii (Holocephali), with special reference to the rectal gland

Osmoregulatory mechanisms in holocephalan fishes are poorly understood except that these fish are known to conduct urea-based osmoregulation as in elasmobranchs. We, therefore, examined changes in plasma parameters of elephant fish Callorhinchus milii, after gradual transfer to concentrated (120%) or diluted (80%) seawater (SW). In control fish, plasma Na and urea concentrations were about 300 mmol l^–1 and 450 mmol l^–1, respectively. These values were equivalent to those of sharks and rays, but the plasma urea concentration of elephant fish was considerably higher than that reported for chimaeras, another holocephalan. After transfer to 120% SW, plasma osmolality, urea and ion concentrations were increased, whereas transfer to 80% SW resulted in a fall in these parameters. The rises in ion concentrations were notable after transfer to 120% SW, whereas urea concentration decreased predominantly following transfer to 80% SW. In elephant fish, we could not find a discrete rectal gland. Instead, approximately 10 tubular structures were located in the wall of post-valvular intestine. Each tubular structure was composed of a putative salt-secreting component consisting of a single-layered columnar epithelium, which was stained with an anti-Na⁺,K⁺-ATPase serum. Furthermore, Na⁺,K⁺-ATPase activity in the tubular structures was significantly increased after acute transfer of fish to concentrated SW (115%). These results suggest that the tubular structures are a rectal gland equivalent, functioning as a salt-secreting organ. Since the rectal gland of elephant fish is well developed compared to that of Southern chimaera, the salt-secreting ability may be higher in elephant fish than chimaeras, which may account for the lower plasma NaCl concentration in elephant fish compared to other chimaeras. Since elephant fish have also attracted attention from a viewpoint of genome science, the availability of fish for physiological studies will make this species an excellent model in holocephalan fish group.

Roman concept of mental capacity to make end-of-life decisions

When assessing decisional competence of patients, psychiatrists have to balance the patients' right to personal autonomy, their condition and wishes against principles of medical ethics and professional discretion. This article explores the age-old legal and ethical dilemmas posed by refusal of vital medical treatment by patients and their mental capacity to make end-of-life decisions against the background of philosophical, legal and medical approaches to these issues in the time of the Younger Pliny (c62–c113 CE). Classical Roman discourse regarding mental competency and "voluntary death" formed an important theme of the vast corpus of Greco-Roman writings, which was moulded not only by legal permissibility of suicide but also by philosophical (in modern terms, moral or ethical) considerations. Indeed, the legal and ethical issues of evaluating the acceptability of end of life decisions discussed in the Letters are as pertinent today as they were 2000 years ago. We may gain valuable insights about our own methodologies and frames of reference in this area of the law and psychiatry by examining Classical Roman approaches to evaluating acceptability of death-choices as described in Pliny's Letters and the writings of some of his peers.

Reconnaissance limnology of Tasmania VII. Coastal lagoons of Bass Strait Islands, with reference to endemic microflora and microfauna

Coastal lagoons of the principal islands of Bass Strait, between Australia's mainland and Tasmania, were sampled in two summers. Many, particularly those of low to moderate salinity, contain relatively rich assemblages of microinvertebrates and some endemic Australian freshwater algae. Several species of testate amoebae and rotifers could not be referred to known morphotypes and are probably new species. The presence of certain species on islands of Bass Strait provides a link between populations in mainland Australia and others in Tasmania. Those lagoons are identified that, by virtue of catchments or buffer zones clothed in native vegetation, are favourable for the survival of a native and partly endemic microbiota.

Observations of the ecological impacts of Sambar Cervus unicolor in East Gippsland, Victoria, with reference to destruction of rainforest communities

Damage caused by Sambar, particularly browsing, antler rubbing and physical removal of particular plant species, is resulting in serious ecological consequences. Threatening processes instigated or maintained by Sambar include: loss of individual taxa, altered vegetation structure and massive
widespread removal and prevention of regeneration, which is now resulting in the loss of plant communities in some areas. These observations are particularly disturbing, as it is apparent that Sambar are yet to reach their full ecological and population potential in south-eastern Australia. The destruction documented ill this article is now so widespread and so severe that in places it represents an ecological disaster for specific plant and animal species, ecological vegetation classes and floristic communities. We strongly recommend that Sambar in particular, and feral deer in general. should no longer be protected under the Wildlife Act 1975 so that control methods can be devised and implemented. It now appears that such measures will he essential for the long-term survival of some fragile plant species and communities in Victoria. (Title: Victorian Naturalist 122(4) 2005, 189-200

Letters to a young Catholic, by George Weigel

With the Twentieth World Youth Day in Cologne on 16-21 August, this year, scheduled to be the first overseas visit of Pope Benedict XVI, it is timely to consider the latest book from George Weigel, (perhaps best known for his Witness to Hope: The Biography of John Paul II) in which he composes 14 letters specifically aimed at young Catholics, who, like many of their older counterparts, may well be wondering what it means to be a Catholic today.

Realizing the dream of R.A. Kartini : her sisters' letters from colonial Java

1. List of Illustrations -- 2. Notes on Text -- 3. Introduction -- 4. ONE Letters from Rockmini -- 5. TWO Letters from Kardinah -- 6. THREE Letters from Kardinah --7. FOUR Letters from Soematri -- 8. Appendix Documents Relating to the Establishment of the Wismo Pranowo School

Congratulations, you're pre-approved! : an analysis of credit limit upselling letters

Consumer Action commissioned Dr Paul Harrison, Deakin Business School, Deakin University and Marta Massi, School of Marketing and Communication, Lumsa University (Rome), to study the psychological aspects of one form of credit marketing – unsolicited credit card limit-increase offers (UCCLIOs). The researchers studied 21 UCCLIO letters – 17 provided by consumers and four provided by banks – and applied theories developed from previous research in the fields of marketing, consumer behavior, behavioural economics and cognitive psychology, to describe likely ways in which UCCLIO’s influenced consumer behavior and decision making. The researchers make some recommendations from a behavioural perspective based on their findings, and Consumer Action proposes how these findings might be applied to consumer policy.