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Research has shown a mixed relationship between education and vaccination rates. In the current analysis, we aimed to determine the relationship between educational level and coronavirus disease 2019 (COVID-19) vaccination rates. We performed a cross-country analysis on data from 133 countries. Correlation analyses showed that higher and better education was associated with higher COVID-19 vaccination rates. When we performed the regression analysis including the education, health system, and economic development variables, education-COVID-19 vaccination relationships were mostly reversed. In particular, in wealthy countries, as the mean years of schooling decreased and the pupil-teacher ratio increased, COVID-19 vaccination rates increased. In less affluent countries, with greater education expenditures, COVID-19 vaccination rates decreased. We explain these contradictions by describing links between vaccination rates, life expectancy, and education-related variables. Our findings may aid in promoting more effective uptake of COVID-19 vaccination.

This study investigated the places of origin of international students and their distribution in the United States higher education. The data concerning the population of international students were obtained from the official website of International Institution of Education (IIE), and transferred into three maps using geographic information systems (GIS) software so that a more direct view of the data was available. The results of the study showed that (1) A larger proportion of international students come from Asian countries; (2) California, New York, and Texas are the top three states hosting international students; (3) most of the universities enrolling international students are located in the eastern part of the country; and (4) the states with already large international student populations experienced a faster growth in the population of international students over the past five years. Some implications for policy planning are discussed at the end of this paper.

The population of the world is growing and moving. The overwhelming majority of people are on the move inside their own country and mostly towards cities while a minority moves from non-Western areas to the West. In Finnish geography, history and social science school textbooks, this mobility tends to be depicted differently depending on whether the movers represent "us" or "them." Global population growth is most prevalent in the poorest regions of the world, even though Europe is clearly the most densely populated continent. Still, the talk of "overpopulation" does not usually concern Europe or the West. The article uses discourse theory analysis and a postcolonial framework to research the discourse of "us" and "them" with regard to population growth and migration as they are presented in Finnish textbooks. The results show that the hegemony of a superior West is alive and well in the books, which portray the non-Western populations as growing and moving in uncontrolled and threatening ways. Uncontrolled urbanization is seen as dangerous, and the implication is that there are too many people in non-Western areas. Metaphors such as natural disasters or floods are used to describe the moving population, while cities are described as "suffocating."

This article examines whether correlates of cross-national homicide variation tested with data from highly developed, predominantly Western nations could also explain homicide rates in East-Central Europe. Using pooled time-series analyses of data from nine countries from 1990 through 2003, this study found that homicide rates were negatively related to GDP/capita and positively related to ethnic diversity and population density. They were also negatively related to the percentage of young people and not significantly related to income inequality or divorce rates. This article also investigates whether conditions specific to the post-communist transformations contributed to homicide variation. Findings indicate that progressive reforms toward democratization and marketization decreased homicide rates. The discussion uses the socio-historical context of the nations to explain these results. (Contains 5 tables and 1 note.)

The early 1990s were marked by the onset of a period of lengthy depopulation in Russia. A number of countries confronted a natural decline in population in the 20th century, in particular Germany, Italy, Bulgaria, Hungary, the Czech Republic, and Sweden. What is specific to Russia, however, is that the depopulation relates to both components of population reproduction, the birth rate and the mortality rate. In other words, depopulation is taking place under pressure from two sides, which distinguishes Russia from the countries of Western Europe. This article examines one aspect of the problem, the declining birth rate. Among numerous factors that influence this process are irreversible shifts in the institution of marriage and the family, noted by researchers in this country and elsewhere. It presents the results of a survey conducted by the Center for Public-Opinion Research in November 2005 and participated in by 1,600 respondents in 46 oblasts, krais, and republics of Russia. The survey was designed to discern the present structure of family values: What are of the most importance to Russians at the present time--matrimonial relations, sexual relations, children, or intergenerational association? Summarizing the results of the survey, given the present type of reproductive behavior, birth control in the home is becoming universally widespread and one of the main factors determining the birth-rate level. (Contains 10 tables and 5 figures.)

Europe and America share a host of similar rural problems but not a common approach to solving them. Social and political differences make it unlikely that we can easily adopt European programs, but observing the similarities can help us understand the global nature of rural development issues. (JHZ)

Introduces special journal issue published to inform American readers of recent developments in Europe and to help readers address contemporary family change. Discusses similarities of trends in North America and Western Europe and points out differences among countries. Examines various statistical indicators and trends in birth rates, marriages, and divorces, and discusses difficulty of interpreting international differences. (NB)

Two water frog species: the pool frog Pelophylax lessonae (L) and the marsh frog P. ridibundus (R) occur sympatrically in Central Europe and form mixed populations (genetic systems) with their hybrid, the edible frog P. esculentus (E). The aim of the study was to assess the species composition of water frogs in urban and rural populations and compare our current findings with the results of previous studies. We surveyed the same sites that were investigated by Berger et al. in 1962–1970 (Poznań, urban landscape) and 1977–1997 (Dezydery Chłapowski Landscape Park, rural landscape). Because some ponds surveyed in the past were destroyed or dried-up, we also explored others located in the adjacent areas. We captured frogs during breeding seasons 2020 and 2021 and identified them by the nuclear marker gene SAI-1. We found three types of populations in the urban area: R-E, E-E and R-E-L and four in the rural area: R-E, L-E, E-E and R-E-L. Compared to the historical data, we found a drastic decrease in the frequency of P. lessonae in urban and rural landscapes: from 89.1% and 68% to 2.7% and 1.8%, respectively. At the same time, the frequency of P. ridibundus increased from 2.2% and 0.1% to 40% and 29.6%, respectively. A similar pattern was found for P. esculentus whose frequency increased from 8.7% and 31.9% to 57.3% and 68.6%, respectively. Additionally, we confirmed the presence of a cryptogenic Balkan water frog, P. kurtmuelleri, which was recently discovered in south-western Poland. The frequency of SAI-1 allele specific for this taxon reached 7.3%. The patterns found in both types of landscapes are in line with the current situation of both parental species in Europe. Such dynamic changes show the need for long-term monitoring of the population compositions of water frogs, what is crucial for their conservation management. [ABSTRACT FROM AUTHOR]

Single phenological measures, like the average rate of phenological advancement, may be insufficient to explain how climate change is driving trends in animal populations. Here, we develop a multifactorial concept of spring phenology—including the onset of spring, spring duration, interannual variability, and their temporal changes—as a driver for population dynamics of migratory terrestrial species in seasonal environments. Using this conceptual model, we found that effects of advancing spring phenology on animal populations may be buffered or amplified depending on the duration and interannual variability of spring green‐up, and those effects are modified by evolutionary and plastic adaptations of species. Furthermore, we compared our modelling results with empirical data on normalized difference vegetation index‐based spring green‐up phenology and population trends of 106 European landbird finding similar associations. We conclude how phenological changes are expected to affect migratory bird populations across Europe and identify regions that are particularly prone to suffer population declines. [ABSTRACT FROM AUTHOR]

Data from existing monitoring schemes point to a global crisis of butterflies across Europe, with habitat loss/degradation, climate change and chemical pollution as the main drivers of decline.The existing butterfly time series from Western Europe come from densely populated, relatively flat areas. However, population trends from less populated areas, such as mountain ranges in the south of Europe, have been less studied, despite these areas harbouring one of the highest butterfly biodiversity of the continent.Here, we analyse trends for butterfly populations in a Southwestern Europe mountain range (Picos de Europa, Northwest Spain), for the last 9 years (2013–2021), across an altitudinal gradient (80–2000 m). We show that this region, protected as National Park more than 100 years ago, is nonetheless under a great threat, with a decline in butterfly abundance of, on average, 5.7% per year (45.7% cumulative decline in the last 9 years).Species at higher elevations are faring worse than those at low elevations and communities at mid‐elevations (below the tree line) are changing towards higher abundance of species with a preference from closed habitats. Combined effects of amplified climate change in mountains and habitat loss, due to abandonment of traditional management, appear to be affecting both individual species and community composition of butterflies in our study area. [ABSTRACT FROM AUTHOR]

Results of the study on bats wintering in underground objects of the Kostrzyn Fortress (Polish-German border zone) revealed the presence of at least 11 species (without distinguishing between Myotis mystacinus and M. brandtii and among species of the genus Pipistrellus). Analysis of long-term changes in the number of animals in regularly surveyed winter roosts showed a positive trend in Myotis myotis and a negative trend in Plecotus auritus. No statistically significant trends have been found in other species, which indicates that the rising numbers of many Central European bat populations have slowed down in the last two decades. Particular winter roosts differed in changes of bat numbers, which was a result of differentiated character of their micro-shelters and changes in microclimate. Similar patterns of changes during the study period were noted in pairs of thermophilic Myotis nattereri and M. daubentonii and in cryophilic P. auritus and Barbastella barbastellus. This indicates that the adopted strategy of wintering significantly affects species response to variable weather conditions during various periods of hibernation. [ABSTRACT FROM AUTHOR]

Recent declines of many European bird species have been linked with various environmental changes, especially land-use change and climate change. Since the intensity of these environmental changes varies among different countries, we can expect geographic variation in bird population trends. Here, we compared the population trends of bird species among neighbouring countries within central Europe (Czech Republic, Denmark, Germany, Switzerland) between 1990 and 2016 and examined trait-associations with population trends at both national and international scales. We found that Denmark had the highest proportion of declining species while Switzerland had the lowest. Species associated with farmland had negative trends, but the effect size tended to differ among countries. A preference for higher temperature was positively associated with population trends and its effect size was similar among countries. Species that were increasing across all four countries were associated with forest; while species that were decreasing across all countries were long-distance migrants or farmland birds. Our results suggest that land-use change tends to be a more regionally variable driver of common bird population trends than climate change in central Europe. For species declining across all countries, international action plans could provide a framework for more efficient conservation. However, farmland birds likely need both, coordinated international action (e.g. through a green agricultural policy) to tackle their widespread declines as well as regionally different approaches to address varying national effect trajectories. [ABSTRACT FROM AUTHOR]

Wildlife conservation policies directed at common and widespread, but declining, species are difficult to design and implement effectively, as multiple environmental changes are likely to contribute to population declines. Conservation actions ultimately aim to influence demographic rates, but targeting actions towards feasible improvements in these is challenging in widespread species with ranges that encompass a wide range of environmental conditions. Across Europe, sharp declines in the abundance of migratory landbirds have driven international calls for action, but actions that could feasibly contribute to population recovery have yet to be identified. Targeted actions to improve conditions on poor-quality sites could be an effective approach, but only if local conditions consistently influence local demography and hence population trends. Using long-term measures of abundance and demography of breeding birds at survey sites across Europe, we show that co-occurring species with differing migration behaviours have similar directions of local population trends and magnitudes of productivity, but not survival rates. Targeted actions to boost local productivity within Europe, alongside large-scale (non-targeted) environmental protection across non-breeding ranges, could therefore help address the urgent need to halt migrant landbird declines. Such demographic routes to recovery are likely to be increasingly needed to address global wildlife declines. [ABSTRACT FROM AUTHOR]

Aim: Global declines in the populations of migratory species have been attributed largely to climate change and anthropogenic habitat change. However, the relative contribution of these factors on species' breeding and non‐breeding ranges is unclear. Here, we present the first large‐scale assessment of the relative importance of climatic conditions and land cover on both the breeding and non‐breeding grounds in driving the long‐term population trends of migratory species. Location: Europe and Africa. Methods: We use data on the long‐term population trends of 61 short‐ and 39 long‐distance migratory species of European breeding birds. We analyse these population trends in relation to changes in climate and land cover across species' breeding and non‐breeding ranges over a 36‐year period, along with species' migratory behaviour. Results: The population trends of European migratory birds appear to be more closely related to changes in climate than changes in land cover on their breeding grounds, but the converse is true on their non‐breeding grounds. While improvements in climate suitability across the breeding ranges of short‐distance migrants led to increasing population trends, the same was not true for long‐distance migrants. The combined effects of changes in climate and land cover account for approximately 40% of the variation in migratory species' population trends, suggesting that factors other than climate and land cover as we have measured them, such as habitat quality, also affect the population trends of migrant birds. Main Conclusions: Over recent decades, population trends of most migrant species are most strongly related to climatic conditions on the breeding grounds but land cover change on the non‐breeding grounds. This suggests that management to stem the declines of migrant birds requires an integrated approach that considers all processes affecting migrant birds across their dynamic distributions throughout the year. [ABSTRACT FROM AUTHOR]

Mast seeding is the episodic, massive production of plant seeds synchronized over large areas. The resulting superabundance of seeds represents a resource pulse that can profoundly affect animal populations across trophic levels. Following years of high seed production, the abundance of both seed consumers and their predators increase. Higher predator abundance leads to increased predation pressure across the trophic web, impacting nonseed consumers such as the wood warbler Phylloscopus sibilatrix through increased nest predation after tree mast years. Over the past 30 years, the frequency of tree seed masts has increased, while wood warbler populations have declined in several regions of Europe. We hypothesized that increasing mast frequencies may have contributed to the observed population declines by creating suboptimal breeding conditions in years after masting. We measured reproductive output in four study areas in central Europe, which was between 0.61 and 1.24 fledglings lower in the years following masting than nonmasting. For each study area, we used matrix population models to predict population trends based on the estimated reproductive output and the local mast frequencies. We then compared the predicted with the observed population trends to assess if the frequency of mast years had contributed to the population dynamics. In Wielkopolska National Park (PL) and Hessen (DE), masting occurred on average only every 4 years and populations were stable or nearly so, whereas in Jura (CH) and Białowieża National Park (PL), masting occurred every 2 and 2.5 years, respectively, and populations were declining. The simple matrix population models predicted the relative difference among local population trends over the past 10-20 years well, suggesting that the masting frequency may partly explain regional variation in population trends. Simulations suggest that further increases in mast frequency will lead to further declines in wood warbler populations. We show that changes in a natural process, such as mast seeding, may contribute to the decline in animal populations through cascading effects., (© 2023 The Authors. Ecology published by Wiley Periodicals LLC on behalf of The Ecological Society of America.)

The little bustard ( Tetrax tetrax ) is a steppe bird strongly and negatively influenced by agricultural intensification in Europe. Here, we use the little bustard as a model species to examine how favourability (relative occurrence likelihood of a species based on environmental characteristics, such as habitat availability) varies regionally with degree of protection in north-western Spain. The Natura2000 network is one of the main biodiversity conservation tools of the European Union, aiming to protect areas hosting species of conservation concern from unfavourable land-use changes. The network covers many landscapes across the continent, including farmland. Additionally, we examine the relationship between trends in land-use favourability and little bustard population trends over a decade in the Nature Reserve of Lagunas de Villafáfila, a protected area also in the Natura2000 network where active and intense management focused on steppe bird conservation is carried out. Favourability was much greater in Villafáfila than in both protected areas with lower degree of protection and in non-protected areas. Land-use favourability increased slightly between 2011 and 2020 both in and out of protected areas, whereas little bustard populations declined sharply in that period, even in Villafáfila. Spatial variations in little bustard abundance within Villafáfila depended on social attraction (increasing with the number of neighbouring males) but not significantly on small-scale variations in land-use favourability. These results suggest that land-use management in Natura2000 areas needs to be more conservation-focused, favouring natural and seminatural habitats and traditional farming practices to improve land-use favourability for little bustards and other steppe birds. Additional factors, such as field-level agricultural management or social interaction variables that may cause an Allee effect, should be incorporated in little bustard favourability models to improve their use in conservation planning., Competing Interests: The authors declare there are no competing interests., (©2024 González del Portillo et al.)

Evidence of declines in insect populations has recently received considerable scientific and societal attention. However, the lack of long‐term insect monitoring makes it difficult to assess whether declines are geographically widespread. By contrast, bird populations are well monitored and often used as indicators of environmental change. We compared the population trends of European insectivorous birds with those of other birds to assess whether patterns in bird population trends were consistent with declines of insects. We further examined whether declines were evident for insectivores with different habitats, foraging strata, and other ecological preferences. Bird population trends were estimated for Europe (1990–2015) and Denmark (1990–2016). On average, insectivores declined over the study period (13% across Europe and 28% in Denmark), whereas omnivores had stable populations. Seedeaters also declined (28% across Europe; 34% in Denmark), but this assessment was based on fewer species than for other groups. The effects of insectivory were stronger for farmland species (especially grassland species), for ground feeders, and for cold‐adapted species. Insectivory was associated with long‐distance migration, which was also linked to population declines. However, many insectivores had stable populations, especially habitat generalists. Our findings suggest that the decline of insectivores is primarily associated with agricultural intensification and loss of grassland habitat. The loss of both seed and insect specialists indicates an overall trend toward bird communities dominated by diet generalists. Article impact statement: Insectivorous bird populations have declined across Europe, whereas omnivorous birds have not. [ABSTRACT FROM AUTHOR]

Dadia-Lefkimi-Soufli National Park forms part of the Natura 2000 network in a region of Greece and represents one of the most diverse landscapes for raptors (birds of prey) breeding in Europe. It is adjacent to Bulgaria and Turkey and is a renowned biodiversity hotspot. WWF Greece established a Systematic Raptor Monitoring scheme in this area in 2001.This study summarises the results of the first 12 years of monitoring in the National Park. Overall, 25 to 27 raptor species were recorded by pooling data, of which20 species reproduced in the National Park. Raptors with continuous presence in the National Park exhibited stable, species-specific inter-annual variation. An average of 348±15.4 raptor territories were distributed throughout the National Park for all species. The Common buzzard (Buteo buteo) and the Shorttoed eagle (Circaetus gallicus) were the most common species year-round, followed by the Lesser-spotted eagle (Clanga pomarina) and Booted eagle (Aquila pennata). The Long-legged buzzard (Buteo rufinus), Honey buzzard (Pernis apivorus) and Egyptian vulture (Neophron percnopterus) exhibited a noticeable drop in population numbers over the study period. A significant new entry was the re-appearance of the Whitetailed eagle (Haliaeetus albicilla), which was recorded breeding again in the region after a 21-year absence. Species trends, along with their ecological traits, are discussed with respect to landscape changes in Dadia NP and minimum viable population and territory thresholds are proposed to outline essential conservation issues. Although a multi-year balance of the total number of occupied territories for all species was recorded, the number of common species increased compared to specialist species which had smaller, de-clining populations. The abandoning of traditional livestock farming, which induces an increase in closedcanopy forest coverage, might have led to the decline of the Lesser-spotted eagle, Long-legged buzzard and Honey buzzard numbers. Additional pressure is added from specialist forest dwelling raptors which are favoured by this change in habitat. The results of this study are expected to provide useful insights to facilitate conservation and management decisions about raptors and their habitat in this region. [ABSTRACT FROM AUTHOR]

The article reports on a study of the common quail (Coturnix coturnix) and the population trends and conservation status in Western Europe. The authors review data since 1900 to the present and they say that reliable predictions on changes in species distribution and their movements during breeding season can provide important information on the conservation status and population trends of the species which can be used in designing measures for management.

Abstract: The European Farmland Bird Indicator (EFBI) has been adopted as a Structural and Sustainable Development Indicator by the European Union. It is an aggregated index integrating the population trends of 33 common bird species associated with farmland habitats across 21 countries. We describe a modelling method for predicting this indicator from land-use characteristics. Using yearly historical land-use data of crop areas derived from the FAO databases (1990–2007) and published population data of farmland birds at the national level for the same period, we developed a series of multiple regression models to predict the trend of the EU state specific indicator, and the EFBI. These models incorporated up to 4 parameters and were selected based upon the significance (p <0.05) of the model inputs with respect to the predictive variable. 17 separate models were developed in total for each of 14 EU countries plus Norway and Switzerland, and a separate model for the EU level indicator. The selected models were then implemented to predict the EFBI in the year 2025, using scenarios of land-use change generated by the CAPRI agricultural model. The uncertainty of using the regression models is discussed with respect to predicting the likely impacts of land-use change on bird populations. This work lays the framework for future modelling of farmland birds at the international scale. [Copyright &y& Elsevier]

1. Abandonment of grasslands is a major threat for the conservation of biodiversity in Europe. The response of butterflies towards secondary succession has been studied in northern temperate grasslands, but always by comparing sites at different seral stages. 2. Here, we present a trajectory study based on the monitoring of butterflies from a series of abandoned grasslands in northeast Spain. One additional meadow was traditionally managed for the whole 8-year sampling period and provided a useful control. Both general changes at the community level and species population trends were documented through standardised transect counts. 3. The increase in turf height was neither accompanied by an increase in butterfly diversity nor by consistent trends in body size, dispersal ability and host-plant specialization. However, there was a significant decrease in habitat specialization, consistent with the hypothesis that richness in generalist herbivores is more dependent on biomass production than on plant richness. The number of generations decreased, in line with the hypothesis that species living in habitats subjected to greater disturbance need higher reproductive rates. 4. Butterfly communities underwent substantial changes, as indicated by composition similarity and species population trends. Grassland specialists were forced to disperse from the abandoned meadows and search for refugial habitats, allowing the establishment of new populations in the contiguous managed meadow. 5. Our study shows that grassland abandonment had immediate strong effects on butterflies, acting as an excellent indicator of habitat change. It also points out to the substitution of grassland specialists by common butterflies, less important for conservation purposes. [ABSTRACT FROM AUTHOR]

Since the first Butterfly Monitoring Scheme in the UK started in the mid-1970s, butterfly monitoring in Europe has developed in more than ten European countries. These schemes are aimed to assess regional and national trends in butterfly abundance per species. We discuss strengths and weaknesses of methods used in these schemes and give examples of applications of the data. A new development is to establish supra-national trends per species and multispecies indicators. Such indicators enable to report against the target to halt biodiversity loss by 2010. Our preliminary European Grassland Butterfly Indicator shows a decline of 50% between 1990 and 2005. We expect to develop a Grassland Butterfly Indicator with an improved coverage across European countries. We see also good perspectives to develop a supra-national indicator for climate change as well as an indicator for woodland butterflies. [ABSTRACT FROM AUTHOR]

It has been argued that Europe needs more immigrants to restore its age structure and its work force. Even if low European fertility continues, decline in the work force is relatively modest in the medium term and is considerably lower than the potential reserve labor force in Europe. It seems eccentric to propose the resumption of immigration for low-grade labor when there are 15 million unemployed in Europe, most under age 25 and many themselves immigrants, especially since future demand for labor emphasizes high skills. A resumption of general immigration to ensure population stabilization would require inflows much higher even than those previously considered unacceptable. Instead, attention should be given to making it easier for women to combine their desires for children with those for work. [ABSTRACT FROM AUTHOR]

The article offers an analysis of the changes in timing of spring arrival of the common cuckoo and its migratory hosts in Europe from 1947-2007. The researchers consider the study as the first evidence which suggest that climate change may influence the link between the life cycles of the common cuckoo and its hosts. They conclude that cuckoos may monitor phenological changes of long-distance but not short-distance migrant hosts, with possible implications for breeding of both cuckoo and hosts.

Although the phenology of numerous organisms has advanced significantly in response to recent climate change, the life-history and population consequences of earlier reproduction remain poorly understood. We analysed extensive data on temporal change in laying date and clutch size of birds from Europe and North America to test whether these changes were related to recent trends in population size. Across studies, laying date advanced significantly, while clutch size did not change. However, within populations, changes in laying date and clutch size were positively correlated, implying that species which advanced their laying date the most were also those that increased their clutch size the most. Greater advances in laying date were associated with species that had multiple broods per season, lived in nonagricultural habitats and were herbivorous or predatory. The duration of the breeding season increased for multibrooded species and decreased for single-brooded species. Changes in laying date and clutch size were not related to changes in population size (for resident or migratory species). This suggests that, across a wide variety of species, mismatches in the timing of egg laying or numbers of offspring have had relatively little influence on population size compared with other aspects of phenology and life history., (© 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.)

This paper sets forth a model for examining the relationships between fourteen policy and politicoeconomic variables, and the social benefits and costs of rehabilitation. Based on discussions in early 1977 with scholars, ministry officials, trade unionists, and politicians in several northwestern European countries, as well as on documentation relating to the rapid growth of disability expenditures and the factors thought to influence it, some "lessons" are presented for policymakers in the United States and other countries. In general, current trends are seen as depressing the post-service earnings of individual rehabilitants, limiting the stabilizing effects of rehabilitation on labor market turnover, and increasing available time for unpaid work in the home and elsewhere. Unequal intergovernmental cost sharing in the provision of benefits and services, it is argued, seems likely to promote inefficient allocation of scarce rehabilitation resources with negative consequences for goal attainment. The high rates of inflation which prevail in the United States and in many northwestern European countries are causing the immediate costs of providing rehabilitation services to rise and simultaneously increasing the opportunity costs of spending for rehabilitation. The net effect of these cost increases is a reduction in the overall benefit/cost ratio that results from investments in rehabilitation. A number of predictions are made about how the United States will shape its disability and rehabilitation policies in the course of the next twenty years.