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Summary: Lévy glass is a new material which is obtained by assembly of scattering elements. The result is a bulk material which has different degrees of elasticity (from rigid as window glass to flexible as certain plastics) and which can be shaped into any desired form. In particular, Lévy glasses have special optical properties not present in other materials. The name Lévy glass is based on the fact that under certain conditions light waves perform a Lévy walk inside these materials and the resulting optical transport is superdiffusive. From a structural point of view a Lévy glass is a random fractal. We will review the optical and structural properties of Lévy glasses, their design criteria, as well as their experimental realization. Also we will go into various fundamental aspects of Lévy-type light transport, discussing both superdiffusion as well as interference effects like weak and strong localization. [ABSTRACT FROM AUTHOR]

Wall collision broadening of absorption lines of gases confined in porous media is a recently opened domain of high-resolution spectroscopy. Here, we present an experimental investigation of its application for pore size assessment. We report on the manufacturing of nanoporous zirconia ceramics with well-defined pore sizes fine-tuned from 50 to 150 nm. The resulting pore structure is characterized using mercury intrusion porosimetry, and the optical properties of these strongly scattering materials are measured using femtosecond photon time-of-flight spectroscopy (transport mean free paths found to be tuned from 2.3 to 1.2 μm as the pore size increase). Wall collision line broadening is studied by performing near-infrared (760 nm) high-resolution diode laser spectroscopy of confined oxygen molecules. A simple method for quantitative estimation of the pore size is outlined and shown to produce results in agreement with mercury intrusion porosimetry. At the same time, the need for improved understanding of wall collision broadening is emphasized. [ABSTRACT FROM AUTHOR]

Summary: We discuss in detail the optical properties of complex photonic structures, in particular those with a dominating disorder component. We will focus on their general transport properties, as well as on their use as light sources (random lasers). The basis for the theory of multiple light scattering in random systems will be explained as a tutorial introduction to the topic, including the explicit calculation of the effect of coherent backscattering. We will discuss various structures that go beyond regular disordered ones, in particular Lévy glasses, liquid crystals, and quasi-crystals, and show examples of their optical properties both from a conceptual and practical point of view. [ABSTRACT FROM AUTHOR]

Peer support groups are rarely available for patients with psychosis, despite potential clinical and economic advantages of such groups. In this study, 106 patients with psychosis were randomly allocated to minimally guided peer support in addition to care as usual (CAU), or CAU only. No relevant differences between mean total costs of both groups were found, nor were there significant differences in WHOQoL-Bref outcomes. Intervention adherence had a substantial impact on the results. It was concluded that minimally guided peer support groups for psychosis do not seem to affect overall healthcare expenses. Positive results of additional outcomes, including a significant increase in social contacts and esteem support, favour the wider implementation of such groups. [ABSTRACT FROM AUTHOR]

In an observational study of severely mentally ill patients treated in assertive community treatment (ACT) teams, we investigated how treatment outcome was associated with demographic factors, clinical factors, and motivation for treatment. To determine psychosocial outcome, patients were routinely assessed using the Health of the Nation Outcome Scales (HoNOS). Trends over time were analyzed using a mixed model with repeated measures. The HoNOS total score was modeled as a function of treatment duration and patient-dependent covariates. Data comprised 637 assessments of 139 patients; mean duration of follow-up was 27.4 months (SD = 5.4). Substance abuse, higher age, problems with motivation, and lower educational level were associated with higher HoNOS total scores (i.e., worse outcome). To improve treatment outcome, we recommend better implementation of ACT, and also the implementation of additional programs targeting subgroups which seem to benefit less from ACT. [ABSTRACT FROM AUTHOR]

Background: Although the effectiveness of individual placement and support (IPS) has been well established, little is known about clients' perceptions of the model compared to usual vocational rehabilitation, nor about their experiences of searching for and returning to work with this kind of support. This qualitative study aimed to explore clients' views of the difficulties of obtaining and maintaining employment, their experiences of the support received from their IPS or Vocational Service workers and the perceived impact of work on clients' lives.Method: Semi-structured interviews were conducted with 48 people with psychotic disorders participating in a six-centre international randomised controlled trial of IPS compared to usual vocational rehabilitation. To assess their experiences of the services and the perceived effects of working, two IPS and two Vocational Service clients at each centre who had found work during the study period were interviewed, along with two IPS and two Vocational Service clients at each centre who had not.Results: IPS clients reported having received more help seeking and maintaining employment, whereas Vocational Service clients reported having received more help in finding sheltered employment or placements. Clients who had worked associated this with financial stability, improved social lives, increased self-esteem, integration into society and amelioration of their symptoms, as well as reduced feelings of boredom and isolation, but also reported increased levels of stress. IPS clients as well as Vocational Service ones reported not receiving enough follow-up support, despite this being proposed as a key feature of the model.Conclusion: Findings from the in-depth interviews reflect differences in service models that have also been tested quantitatively but further work in disaggregating the IPS model and assessing the impact of each component would be valuable. [ABSTRACT FROM AUTHOR]

The effectiveness of a rehabilitation intervention (Boston University Model) was investigated in a one-year prospective naturalistic study among 35 clients with mainly psychotic or affective disorders and dependent on mental health care with at least one hospital admission in the past five years. Rehabilitation was successful in goal-attainment after 1 year (46% fully, 34% partly). Although rehabilitation did not make clients less dependent upon care, it decreased the number of needs and had a positive effect on the match between care needed and care provided. No evidence was found for a significant effect of rehabilitation clients' quality of life and functioning, although social functioning became more in line with the seriousness of psychiatric impairment. [ABSTRACT FROM AUTHOR]

Background: In the Netherlands, a previous study has shown an increase in the 1-year prevalence of patients in mental health care during the 1990s. Though the number of inpatients decreased, this decrease was far outweighed by a large increase of patients in community care, causing an increase in total year prevalence. The current study aimed at an explanation.Methods: The Groningen psychiatric case register was used to determine treated incidence and prevalence over a 9-year period for different age groups.Results: Incidence rates proved fairly stable. The increased prevalence was primarily caused by the growing number of existing cases. People had their first encounter with mental health care at an earlier age and remained in care for a larger part of their life.Conclusions: Results indicate that the accessibility of Dutch mental health care was increased by the implementation of community care. In contrast to other countries, Dutch community care lowered the threshold for mental health care utilization without broadening the target group of mental health services. [ABSTRACT FROM AUTHOR]

Background: In the Netherlands there has been no distinct period of deinstitutionalization or transinstitutionalization of mental health care. Rather, the Dutch government expects local mental health services to reform their joint service provision without forceful measures like cutting budgets of large mental hospitals. This study aimed at quantifying gradual changes in the use of community- and hospital-based care.Methods: The Groningen psychiatric case register was used to determine the number of users and the amount of use of mental health services. Changes in population size and age distribution were accounted for by means of demographic data.Results: The number of users of innovative psychiatric treatment modalities more than tripled between 1989 and 1997. In the same period, the volume of traditional inpatient care gradually decreased. This was caused primarily by a reduction in the length of stay in the hospital.Conclusions: These findings seem to support the effectiveness of Dutch substitution policy. However, there is also a cause for concern. Though people use new mental health care provisions, there is a rapidly growing number of them who do so. [ABSTRACT FROM AUTHOR]

Need for care was studied in a Dutch incidence cohort of patients with schizophrenic disorders 15 and 17 years from first onset of psychosis. Long-term course of the disorders varied from complete remission and full community participation to chronic psychosis and long-term hospital stay. Fifty patients were assessed twice with the Needs For Care Assessment Schedule (NFCAS, Brewin and Wing 1989); at the latter follow-up an assessment was also made using the Camberwell Assessment of Need (CAN, Phelan et al. 1995). The NFCAS is an investigator- or professional-based instrument which provides an 'objective' assessment of needs. Need for care was recorded in 22 areas of clinical and social functioning. Comparison of the two assessments over a 2-year period demonstrated a high stability on the individual items (mean 88%, mostly concerning the absence of a problem twice), but did not show the expected stability of need status among this group of patients with chronic disorders. One in five patients (22%) had no needs at all on both occasions and 56% of the patients showed a change in needs. There was more negative than positive change: 28% suffered from new unmet needs at the 17-year follow-up, while only 12% had improved their status to no needs. About one-third (36%) had at least one unmet need, mostly regarding psychotic symptoms, dyskinesia or underactivity. The CAN provides a 'subjective' assessment of needs according to the view of patients themselves. The problems patients reported most commonly were in the areas of day-time activities, social relationships and information on their condition and treatment, for all which they asked for more help than they received. This patient-based instrument produces slightly higher numbers of problems and unmet needs, and a lower ratio between met and unmet needs. There is an overall percentage of 21% of disagreement between patient and investigator view regarding the unmet need status. Agreement between the two instruments on the nature of the problems with unmet needs was lacking altogether. [ABSTRACT FROM AUTHOR]

Social functioning is important in relation to mental illness as it can limit the ability to function independently and because it may vary separately from symptoms. This paper summarises and critically reviews the development of the WHO Classification of Impairments, Disabilities and Handicaps. The value of social role theory is described followed by a classification of the relevant assessment scales in this field. Mental disorders are in general strongly associated with social dysfunctioning, particularly in schizophrenia and the major affective disorders. For a long time social dysfunctioning was considered an epiphenomenon and just a part of the disease process. Criteria for the diagnosis of a mental disorder were and still are often derived from the domains of work and social relationships. There are at least two related reasons why social functioning deserves a closer look: The usual diagnostic systems such as the ICD and the DSM offer no adequate solution to the problem of classification and assessment of social dysfunctioning as a consequence of mental disorder. We have to look for other classification systems such as the International Classification Impairments, Disabilities and Handicaps (ICIDH) of the WHO (1980, 1993) which offers a conceptual model to study the long-term consequences in terms of functional disabilities and experienced social handicaps, and the effectiveness of health care to handle these kind of problems. [ABSTRACT FROM AUTHOR]

Assessment of needs for care is crucial in the evaluation of ongoing changes from institutional care to various forms of day- and outpatient treatment. Do patients really do better in the community and are they adequately cared for? The 15-year follow-up of a Dutch incidence cohort of patients with schizophrenia and other functional non-affective psychoses showed that 47 (out of 63) patients had positive ratings of symptoms and disabilities. They were assessed by means of the Needs for Care Assessment Schedule, which articulates the problems and corresponding interventions resulting in a judgement of met or unmet need for treatment or assessment. There was a mean of 2.1 clinical problems and 2.1 social problems per patient. Few problems were considered to generate unmet needs: 14% of the clinical problems and only 7% of the social problems. Nevertheless, 32% of the patients had one or more unmet needs. These results were compared with data from six research centres in the United Kingdom (Camberwell, Oxford and South Glamorgan), Canada (Montreal), Italy (Verona) and Finland (Tampere). Despite differences in health care settings in the four countries, the ratio of met to unmet needs (about 4-5 to 1) among chronic, mostly schizophrenic patients is more or less the same with the exception of an apparently underserved hostel population in Oxford and the Finnish patient population probably due to high expectations with respect to independent community living. [ABSTRACT FROM AUTHOR]

The relationship between symptomatology and social functioning was investigated. Data were derived from a Dutch cohort of 82 patients with a first life-time episode of non-affective, functional psychosis, who participated in the WHO Collaborative Study on the Assessment and Reduction of Psychiatric Disability. Correlations between scores on two unidimensional, hierarchical rating scales in the 3 years after onset of illness were examined and a comparison was made between course of symptomatology and social disability. The relationship was found to be rather weak, a conclusion that is somewhat in variance with earlier studies. It is conjectured that this may partly be explained by the fact that different study methods were used. [ABSTRACT FROM AUTHOR]

The course of the psychopathology and social functioning in an experimental day-treatment group referred for inpatient psychiatric treatment is compared with that of a control group receiving standard inpatient care. During a follow-up period of 2 years subjects were interviewed three times. The interview comprised information about psychiatric symptoms, psychological functions, psychiatric diagnosis and social-role functioning. Apart from these discrete assessments an effort was made to map episodes of illness throughout the follow-up period. Upon entry the groups did not differ in terms of psychopathology or social functioning. At follow-up both groups had improved significantly with respect to symptomatology, psychological and social functioning. The extent to which the groups improved did not differ significantly regarding pathology, but self-care improved more in the experimental group. The average duration of episodes of illness was similar for the experimental and control group. During the 2-year follow-up patients suffered from a well-defined disorder during an average of 11 months. The fact that approximately 40% of them were still a psychiatric case after 2 years further underscores the severity of their pathology. [ABSTRACT FROM AUTHOR]

Recent literature shows a lively debate on how to capture ecologicaland environmental aspects in different evaluation methods and the closely related issue of the (im)possibilities of monetization of theseaspects. Although economists in general tend to favour Cost-Benefit Analysis (CBA) above Multi-Criteria Analysis (MCA), part of the literature suggests that CBA falls short of being the only decision-makingdevice for environmental problems, both for theoretical and practical reasons. This paper discusses both evaluation methods and the main results of a major, publicly-financed nature conservation project in The Netherlands. The evaluation method combines the straightforwardness of CBA with the flexibility of MCA. Conceptually, it consists of aMCA, the net result of a CBA being integrated as one of the criteria. The different aspects of the nature conservation project that can be monetized are incorporated into the CBA. Other aspects such as changes in biodiversity or scenic beauty are analysed in their own dimension, provided (cardinal) quantification is possible. In fact, the analysis consists of a very simple MCA, with two criteria: social costs and a quantitative measure of nature. Quantifying the amount of nature in its own, non-monetary dimension is a key element of the empirical analysis. A detailed quantitative estimate is made of the improvement of nature, based upon 564 species and 131 different ecosystems. The result of the evaluation is a trade-off at the national level between ecological improvements (plus 18 percent) and social costs (DFl. 3.4 billion net present value). Due to the detailed quantification of the effect on nature the evaluation also yields results about the cost-effectiveness of four different instruments to create and to preserve nature. That part of the analysis shows that complete withdrawal of agricultural land for nature purposes in the project in general is more cost-effective than subsidizing nature-friendly farming, although th [ABSTRACT FROM AUTHOR]

The paper discusses efficiency issues in the public provision of environmental services, in particular waste water treatment. It is shownthat in the face of increasing, respectively decreasing returns to scale the zero profit constraint of a cost minimizing public firm induces underinvestment, respectively overinvestment in public capacity compared with efficient allocation between public purification and effluent control by private polluters. X-inefficiency of the public firmcounter-acts the inefficiency in allocation arising from overinvestment, and it reinforces the inefficiency in allocation in case of underinvestment in public purification capacity. As subsidy can bring down the user's charge imposed on sources, but it will also increase X-inefficiency. The subsidy counteracts underinvestment but reinforces overinvestment in public capacity. [ABSTRACT FROM AUTHOR]