Comet-like mineralogy of olivine crystals in an extrasolar proto-Kuiper belt.

Some planetary systems harbour debris disks containing planetesimals such as asteroids and comets. Collisions between such bodies produce small dust particles, the spectral features of which reveal their composition and, hence, that of their parent bodies. A measurement of the composition of olivine crystals (Mg(2-2x)Fe(2x)SiO(4)) has been done for the protoplanetary disk HD 100546 (refs 3, 4) and for olivine crystals in the warm inner parts of planetary systems. The latter compares well with the iron-rich olivine in asteroids (x ≈ 0.29). In the cold outskirts of the ß Pictoris system, an analogue to the young Solar System, olivine crystals were detected but their composition remained undetermined, leaving unknown how the composition of the bulk of Solar System cometary olivine grains compares with that of extrasolar comets. Here we report the detection of the 69-micrometre-wavelength band of olivine crystals in the spectrum of ß Pictoris. Because the disk is optically thin, we can associate the crystals with an extrasolar proto-Kuiper belt a distance of 15-45 astronomical units from the star (one astronomical unit is the Sun-Earth distance), determine their magnesium-rich composition (x = 0.01 ± 0.001) and show that they make up 3.6 ± 1.0 per cent of the total dust mass. These values are strikingly similar to those for the dust emitted by the most primitive comets in the Solar System, even though ß Pictoris is more massive and more luminous and has a different planetary system architecture.

Warm water vapour in the sooty outflow from a luminous carbon star.

The detection of circumstellar water vapour around the ageing carbon star IRC +10216 challenged the current understanding of chemistry in old stars, because water was predicted to be almost absent in carbon-rich stars. Several explanations for the water were postulated, including the vaporization of icy bodies (comets or dwarf planets) in orbit around the star, grain surface reactions, and photochemistry in the outer circumstellar envelope. With a single water line detected so far from this one carbon-rich evolved star, it is difficult to discriminate between the different mechanisms proposed. Here we report the detection of dozens of water vapour lines in the far-infrared and sub-millimetre spectrum of IRC +10216 using the Herschel satellite. This includes some high-excitation lines with energies corresponding to approximately 1,000 K, which can be explained only if water is present in the warm inner sooty region of the envelope. A plausible explanation for the warm water appears to be the penetration of ultraviolet photons deep into a clumpy circumstellar envelope. This mechanism also triggers the formation of other molecules, such as ammonia, whose observed abundances are much higher than hitherto predicted.

Self-assessed health among indigenous Australians: how valid is a global question?

OBJECTIVES: This study assessed the validity of a global measure of self-assessed health among Indigenous Australians. METHODS: Logistic regression was used to identify factors associated with self-assessed health in a nationally representative sample. RESULTS: Among 8782 adult respondents, poorer self-assessed health was strongly associated with several factors, including age, number of health conditions, and recent health actions. The association with health conditions was attenuated when the respondent's primary language was not English. CONCLUSIONS: Self-assessed health may be a valid measure among indigenous Australians whose primary language is English. However, although the measure draws on common experiences of health and illness, it may obscure differences in how people incorporate these experiences into social actions.

[Meta-analysis of the Cochrane Collaboration. Promoting collaboration between nurses and physicians]. / Metanalisi della Cochrane Collaboration. Interventi per promuovere la collaborazione tra infermieri e medici.

The aim of this systematic review of the Cochrane Collaboration was to assess the impact of interventions designed to change nurse-doctor collaboration on collaboration itself, on patient satisfaction, and on the effectiveness and efficiency of the health care provided. There are no good trials on interventions to improve collaboration between doctors and nurses. There are numerous strategies suggested to improve inter-disciplinary collaboration between doctors and nurses, such as joint workshops, meetings, development of team systems and strategies, and training in collaboration. However, no studies of these interventions that met the reviewers' criteria could be found. More research is needed to determine any impact of these strategies on interprofessional collaboration, and on the outcomes for patients.

The long-term impact of childhood sexual abuse in Australian women.

OBJECTIVE: The aim of this study was to examine the association between childhood sexual abuse (CSA) and a range of adverse adult outcomes in a community sample of women using multivariate analysis which accounted for a number of potential confounding effects. METHOD: Retrospective study of cross-sectional data on the long-term impact of CSA, collected as part of a larger two-stage case-control study of the possible relationship between CSA and alcohol abuse. Data were appropriately weighted to adjust for the different selection probabilities of cases and controls. RESULTS: Significant associations were found between reporting CSA and experiencing domestic violence, rape, sexual problems, mental health problems, low self-esteem, and problems with intimate relationships even after taking into account a range of family background factors. Women who had experienced abuse involving intercourse were the most vulnerable to these negative outcomes. CONCLUSIONS: The findings indicate that the influence of CSA on adverse long-term effects is mediated and influenced both by the severity of the abuse experiences and by a range of family and social background factors.

Positions and training of the indigenous health workforce.

A survey of community-controlled and state health services was conducted in 1995 as part of a needs assessment for a tertiary training initiative in applied epidemiology. Information for 792 Indigenous people in health-related occupations was obtained. Mean time in the current position was 4.8 years, 75% were in designated Aboriginal positions and 44% were health workers. Of the total, 49% had a diploma or certificate, but only 3% had a bachelors degree. The latter compares with 75% of the public health workforce generally which has a bachelors degree or higher. The high proportions of health worker and designated Aboriginal positions, short tenure and low level of degree training suggest that there are a range of employment and training issues which need to be addressed if an appropriate level of Indigenous workforce participation is to be achieved and Indigenous health professionals are to have access to the same vertical and lateral employment mobility as non-Indigenous workers. In particular, there is a huge need to enhance Indigenous participation in health workforce training, and to develop strategies for certification and recognition of the wide range of non-course-based training being undertaken.

Data for diagnosis, monitoring and treatment in indigenous health: the case of cervical cancer.

Deficiencies in the availability and quality of data on the health status of indigenous Australians have long been recognised. For cervical cancer, data demonstrate a 2-5 fold greater incidence rate and an 8-10 fold greater mortality rate for Indigenous women compared to non-Indigenous Australians. However, incidence and mortality data are only available for some states and there is little or no information available on the geographic or social distribution of risk, or the reasons for risk differentials. There are also little or no data on the utilisation of, or preferences for, screening services. Thus, while there is clearly a need for a cervical cancer control program specifically to target Indigenous women, current data are inadequate to inform planning and implementation, and current systems are inadequate to monitor effectiveness. This situation is the result of insufficient research and inadequate attention to recording of Indigenous status in routine data systems and applies to a greater or lesser extent across the spectrum of health of Indigenous Australians. Health workers across the spectrum in mainstream and Indigenous medical services have a shared responsibility for improving the availability and quality of data and ensuring the appropriate use of information necessary to achieve and monitor improvements in service delivery and health status of Indigenous people.

Mixed feelings: satisfaction and disillusionment among Australian GPs.

BACKGROUND AND AIMS: Medical practitioners' satisfaction with their work impacts on quality of care for their patients and on their own sense of fulfillment. Reforms introduced in the early 1990s into Australian general practice have led to concerns over the morale of GPs. This study examines satisfaction and dissatisfaction of GPs with regard to the reform strategy. METHOD: GPs throughout Australia were approached via a popular GP magazine to express their views in a questionnaire comprising closed-end and open-ended questions enquiring about satisfaction with their current role and sources of satisfaction (and dissatisfaction) of working in general practice. Factor analysis was used to identify different sources of satisfaction (and dissatisfaction), which were intercorrelated and which together represented underlying factors. Logistic regression modelling was used to determine which sources were most strongly associated with being satisfied (or not satisfied), and to explore GP characteristics associated with satisfaction. RESULTS: A total of 2186 questionnaires were returned, representing the opinions of 14-18% of Australian GPs. Two-thirds (68%) of respondents reported being satisfied, most frequently with the variety of work and establishing relationships with patients and their families. Six satisfaction factors were identified on factor analysis, the most important characterizing social and interpersonal roles. Leading sources of dissatisfaction related to perceived interference by the government. Six dissatisfaction factors were identified on factor analysis, the most important characterizing governmental issues. However, on logistic regression other sources of dissatisfaction (reflecting disillusionment) were most strongly associated with not being satisfied. CONCLUSIONS: The main sources of satisfaction are those which typify the long-term caring role of the community GP. While the reform strategy aimed to address problems with the organization and financing of general practice, the resulting intervention is the focus of dissatisfaction. Among dissatisfied GPs these attitudes may arise primarily from a sense of disillusionment.

The relationship between childhood sexual abuse and alcohol abuse in women--a case-control study.

AIMS: The aim of this paper was to examine the association between reporting childhood sexual abuse (CSA) and alcohol abuse in a community sample of women using multivariate analysis which took into account a range of potential confounding variables (such as a family history of alcoholism) and effect modifiers (such as having an alcoholic partner). DESIGN: A two-stage retrospective case-control study was used to investigate the relationship between reporting CSA and alcohol abuse in women. PARTICIPANTS: Seven hundred and ten women randomly selected from the Australian federal electoral rolls. MEASUREMENTS: The Alcohol Use Disorders Identification Test (AUDIT) was used to measure alcohol abuse. A series of questions based on those developed by Wyatt (1985) were used to ascertain the prevalence of CSA. FINDINGS: The final model showed that the relationship between a history of CSA and alcohol abuse reflected a complex interaction between CSA and a range of other factors in a woman's background. CSA was not by itself a significant predictor of alcohol abuse (OR = 0.61; 95% CI = 0.31-1.20). However, a history of CSA became significant in combination with co-factors which included: having a mother who was perceived as cold and uncaring; having an alcoholic partner; and believing that alcohol is a sexual disinhibitor. CONCLUSION: This study indicates that CSA alone is not a causative factor in the development of alcohol abuse among women and highlights the importance of examining the family background of women with alcohol problems.

General practitioners' perceptions regarding coordinated care.

OBJECTIVE: To explore the attitudes of general practitioners to the changing roles in the coordination of complex patient care. METHOD: A questionnaire survey was distributed with Australian Doctor. RESULTS: GPs were found to fall into four broad groups in relation to care coordination: those who do not want to expand their role in coordination of care (30%); those who would like to expand their role in coordination of care, but do not want to take costs into account when making decisions about patient care (34%); those who would like to expand their role in coordination of care, do think costs should be taken into account, but do not wish to be involved in budget management (21%); and those who would like to expand their role in coordination of care and be involved in budget management (22%). CONCLUSION: In the context of the introduction of managed care in Australia, this survey highlights the potential for GPs to take on a range of roles and responsibilities under these arrangements.

The response of injection drug users to free treatment on demand: implications for HIV control.

Injection drug use is a major risk factor for human immunodeficiency virus (HIV) infection and drug treatment is widely recognized as a core component of the public health effort to limit the spread of HIV. The assumption is frequently made that lack of immediate access to treatment is a significant barrier to the success of this effort. However, little empirical data exist to support this belief. We conducted a trial of no-cost outpatient drug-free treatment made available on demand to a cohort of out-of-treatment injection drug users (IDUs) in Portland, Oregon, through a coupon program. Of 824 IDUs, 272 (33%) expressed an interest in treatment, 225 (27%) accepted a coupon, 66 (8%) redeemed a coupon, and 9 (1%) remained in treatment for 6 months. These numbers indicate that simply enhancing access is not adequate. Additional strategies to increase motivation to enter and remain in treatment are needed if drug treatment is to play an important role in reducing the spread of HIV among injection drug users, their sexual partners, and their infants.

Drug use, binge drinking and attempted suicide among homeless and potentially homeless youth.

In order to assess the need for drug-related services for at-risk youth, a survey was conducted among young people aged 12-17 years who, owing to severe family discord, were currently living away from home (homeless) or had experienced periods away from home in the past 12 months (potentially homeless). Prevalence of use and of potentially harmful levels of use of alcohol and other licit and illicit drugs were higher than in a comparative population. Of the 155 people interviewed, 54% reported past physical abuse, 28% reported past sexual abuse, and 73% had a family alcohol or other drug history. Of the total, 62% had been in a youth refuge at some time in the past 12 months. Twenty four per cent had been to hospital as a result of alcohol or other drug use and 45% had attempted suicide. Female sex and an interaction between sexual abuse and binge drinking predicted suicide attempts. This study points to the need for a comprehensive approach to interventions for troubled youth which gives greater recognition to mental health issues related to family circumstances, including abuse.

Record linkage in Australian epidemiological research: health benefits, privacy safeguards and future potential.

Epidemiologists are increasingly concerned with the health effects of interventions and of exposure to noninfectious agents, but there may be long periods between exposure and outcome. Collecting information from respondents is a costly and often inefficient way of obtaining the longitudinal data necessary to study these effects. Linking existing data can be an effective and efficient alternative. However, it is often not practicable to obtain informed consent from the individuals whose records are to be linked. This raises important issues relating to protection of privacy. This paper examines the health benefits and privacy issues of epidemiological and health services research involving record linkage in Australia. The future potential for studies based on record linkage is discussed in the context of recent national and international developments in data protection. In the interests of public health and the rational use of health resources a balance must be struck between protecting individual privacy and conducting such health research for the common good.

Circumstances surrounding needle use transitions among injection drug users: implications for HIV intervention.

Injection drug users (IDUs) are at increased risk of infection with the human immunodeficiency virus (HIV). Intervention programs aimed at reducing the spread of HIV in this population typically incorporate a range of risk reduction strategies, including encouragement to move from injection to noninjection. However, very little is known about the factors associated with needle use transitions, either spontaneous or in response to intervention. We report a study in which a cohort of IDUs were asked about the reasons they stopped and restarted injection. Of 855 IDUs, 179 (21%) had had a least one 12-month period of noninjection since they first injected. Almost one-half of the reasons given for stopping injecting related to personal crises, characterized by major shifts in attitude to drugs and/or life more generally, and often generated by pressures in significant relationships. Concerns about HIV were cited by only one respondent. Many of the factors associated with transition out of needle use in the study population are not readily amenable to intervention. The implications of this for HIV risk reduction programs are discussed.

Self-help groups: a key to HIV risk reduction for high-risk injection drug users?

While recent studies indicate that injection drug users (IDUs) can change their behavior to reduce injection risk of HIV, it remains unclear which users are most likely to change and which mediating variables are most amenable to intervention. We report a study in which a cohort of high-risk IDUs was followed over time to determine which variables were associated with reduced injection risk of HIV. Of 317 IDUs who at baseline had shared a dirty needle in the previous 30 days, 234 (74%) were followed for 6 months. Of these, 107 (46%) reported reduced or eliminated injection risk between the baseline and follow-up interviews, 82 (35%) by not injecting and 25 (11%) by not sharing syringes. Those who attended self-help meetings between the two interviews were almost twice as likely to report reduced or eliminated risk as those who did not attend (OR = 1.92; p = 0.04). The findings suggest that, at least, IDUs in self-help groups comprise a population amenable to HIV interventions and, at most, that self-help groups may play an important role in reducing the risk of HIV in out-of-treatment populations.