Cross-national comparison of internal migration: issues and measures

Our objectives are to identify the issues that researchers encounter when measuring internal migration in different countries and to propose key indicators that analysts can use to compare internal migration at the 'national' level. We establish the benefits to be gained by a rigorous approach to cross-national comparisons of internal migration and discuss issues that affect such comparisons. We then distinguish four dimensions of internal migration on which countries can be compared and, for each dimension, identify a series of summary measures. We illustrate the issues and measures proposed by comparing migration in Australia and Great Britain.

Eugenics or empowered choice? Community issues arising from prenatal testing

The prevention of inherited disabilities is viewed in two contrasting ways – either as enhancing reproductive choice and improving population health, or as discriminating against disabled community members. We argue that modern clinical genetics, including preimplantation genetic diagnosis (PGD), reflects a persistent and defensible desire by the community to prevent disability, rather than as increasing discrimination or threatening to produce a 'new eugenic' society. Screening should be presented as a distinct issue for decision-making about the prevention or acceptance of disability, rather than as a routinely accepted component of antenatal care. The community must improve its understanding of the experiences of those who manage disability, and continue to debate the issues of discrimination, selective genetic prevention and enhancement, reproductive freedom, and eugenics.

Are transitions in human gait determined by mechanical, kinetic or energetic factors?

It is currently unclear whether it is the need to maintain metabolic efficiency, the need to keep skeletal loading below critical force levels, or simple mechanical factors that drive the walk-to-run (W R) and run-to-walk (R-W) transitions in human gait. Eighteen adults (9 males and 9 females) locomoted on an instrumented treadmill using their preferred gait. Each completed 2 ascending (W-R) and 2 descending (R-W) series of trials under three levels of loading (0%, 15% and 30% body weight). For each trial, participants locomoted for 60 s at each of 9 different speeds -4 speeds both above and below their preferred transition speed (PTS) plus their PTS. Evidence was sought for critical levels of key kinetic (maximum vertical force, impulse, first peak force, time to first peak force and maximum loading rate), energetic (oxygen consumption, transport cost) and mechanical variables (limb lengths, strength) predictive of the gait transition. Analyses suggested the kinetic variables of time to first peak force and loading rate as the most likely determinants of the W-R and R-W transitions. (C) 2003 Elsevier Science B.V. All rights reserved.

High dependency units: Issues to consider in their planning

This review discusses the issues to be considered in establishing new or extending existing high dependency unit (HDU) services. A defined high dependency service becomes cost-effective when patient care requires more than one nurse for three patients. Professional guidelines for HDUs vary and there are no national accreditation criteria. Casemix and service delivery specifications for the HDU need to be defined and agreed upon within the institution. Establishing a new HDU service requires changes to care delivery. Many potential HDU patients are currently managed in general wards or in the intensive care unit. The service should be discussed widely and marketed within the institution, and the development of defined working relationships with the ICU and primary care teams oil the wards is mandatory.

Issues in Australian Foreign Policy: January to June 2002

No abstract

Mixed gas equilibrium adsorption on zeolites and energetic heterogeneity of adsorption volume

A model for binary mixture adsorption accounting for energetic heterogeneity and intermolecular interactions is proposed in this paper. The model is based on statistical thermodynamics, and it is able to describe molecular rearrangement of a mixture in a nonuniform adsorption field inside a cavity. The Helmholtz free energy obtained in the framework of this approach has upper and lower limits, which define a permissible range in which all possible solutions will be found. One limit corresponds to a completely chaotic distribution of molecules within a cavity, while the other corresponds to a maximum ordered molecular structure. Comparison of the nearly ideal O-2-N-2-zeolite NaX system at ambient temperature with the system Of O-2-N-2-zeolite CaX at 144 K has shown that a decrease of temperature leads to a molecular rearrangement in the cavity volume, which results from the difference in the fluid-solid interactions. The model is able to describe this behavior and therefore allows predicting mixture adsorption more accurately compared to those assuming energetic uniformity of the adsorption volume. Another feature of the model is its ability to correctly describe the negative deviations from Raoult's law exhibited by the O-2-N-2-CaX system at 144 K. Analysis of the highly nonideal CO2-C2H6-zeolite NaX system has shown that the spatial molecular rearrangement in separate cavities is induced by not only the ion-quadrupole interaction of the CO2 molecule but also the significant difference in molecular size and the difference between the intermolecular interactions of molecules of the same species and those of molecules of different species. This leads to the highly ordered structure of this system.

Postpartum issues' for expectant mothers and fathers

Objective: To investigate the postpartum psychosocial and infant care topics that women and men who attend preparation for parenthood classes have been thinking or worrying about during the pregnancy. Furthermore, to compare the rates of endorsement of such issues for women and men so that clinicians can use this information to help plan which topics to include in preparation for parenthood classes. Design: A survey of expectant parents attending preparation for parenthood classes at a local public hospital. Participants completed a 17- to 19-item postpartum issues checklist devised for the study. Setting: Preparation for parenthood classes conducted in a public hospital in South Western Sydney, Australia. Participants: People attending the session were in their 2nd to 3rd trimester, of low to middle socioeconomic status, and 95% were expecting their first child. Eighty-five percent of women were accompanied by their male partner at the session. Data are reported from 201 women and 182 men. Measure: A 17-item issues checklist was devised initially and later expanded to 19 items. The initial checklist covered three psychosocial issues: interpersonal, intrapersonal, and parental competency. The expanded checklist also included items on infant care issues. Participants rated each item as to the extent to which they had been thinking or worrying about it over the past few weeks. Results: More than half of the men and women had been thinking or worrying about their ability to cope as new parents; just less than half of both men and women endorsed the item regarding the effect having a baby would have on their relationship with their partner; approximately 40% of women had thought that they might get bored or lonely when at home with the baby, and an equal rate of men reported that their partner experiencing this sense of boredom or loneliness was an issue for them. There were few differences between the genders in the rate of endorsement on the issues checklist. Conclusion: That many of the issues on the checklist are prevalent in both women and men at this time in the pregnancy would suggest that these are topics that would be pertinent for inclusion at preparation for parenthood classes. Although the checklist is not exhaustive, the data reported give empirical justification for inclusion of these topics in such classes.

Energetic costs of tail loss in a montane scincid lizard

Most species of lizards will shed their tails at the point of contact when grasped by a predator. We investigated the energetic consequences of tail loss by measuring lipids in a scincid lizard that stores energy in its tail for reproduction. Most of the lipids were concentrated in the proximal portion of the tail. Thus, partial tail loss may not severely affect energy stores if the distal portion of the tail is shed in predatory encounters. We also found that the width of the tail was a reliable non-invasive index of energy reserves in this species. (C) 2003 Elsevier Science Inc. All rights reserved.