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A comprehensive European dataset on monthly atmospheric NH3, acid gases (HNO3, SO2, HCl), and aerosols (NH4+, NO3-, SO42-, Cl−, Na+, Ca2+, Mg2+) is presented and analysed. Speciated measurements were made with a low-volume denuder and filter pack method (DEnuder for Long-Term Atmospheric sampling, DELTA®) as part of the EU NitroEurope (NEU) integrated project. Altogether, there were 64 sites in 20 countries (2006–2010), coordinated between seven European laboratories. Bulk wet-deposition measurements were carried out at 16 co-located sites (2008–2010). Inter-comparisons of chemical analysis and DELTA® measurements allowed an assessment of comparability between laboratories. The form and concentrations of the different gas and aerosol components measured varied between individual sites and grouped sites according to country, European regions, and four main ecosystem types (crops, grassland, forests, and semi-natural). The smallest concentrations (with the exception of SO42- and Na+) were in northern Europe (Scandinavia), with broad elevations of all components across other regions. SO2 concentrations were highest in central and eastern Europe, with larger SO2 emissions, but particulate SO42- concentrations were more homogeneous between regions. Gas-phase NH3 was the most abundant single measured component at the majority of sites, with the largest variability in concentrations across the network. The largest concentrations of NH3, NH4+, and NO3- were at cropland sites in intensively managed agricultural areas (e.g. Borgo Cioffi in Italy), and the smallest were at remote semi-natural and forest sites (e.g. Lompolojänkkä, Finland), highlighting the potential for NH3 to drive the formation of both NH4+ and NO3- aerosol. In the aerosol phase, NH4+ was highly correlated with both NO3- and SO42-, with a near-1:1 relationship between the equivalent concentrations of NH4+ and sum (NO3-+ SO42-), of which around 60 % was as NH4NO3. Distinct seasonality was also observed in the data, influenced by changes in emissions, chemical interactions, and the influence of meteorology on partitioning between the main inorganic gases and aerosol species. Springtime maxima in NH3 were attributed to the main period of manure spreading, while the peak in summer and trough in winter were linked to the influence of temperature and rainfall on emissions, deposition, and gas–aerosol-phase equilibrium. Seasonality in SO2 was mainly driven by emissions (combustion), with concentrations peaking in winter, except in southern Europe, where the peak occurred in summer. Particulate SO42- showed large peaks in concentrations in summer in southern and eastern Europe, contrasting with much smaller peaks occurring in early spring in other regions. The peaks in particulate SO42- coincided with peaks in NH3 concentrations, attributed to the formation of the stable (NH4)2SO4. HNO3 concentrations were more complex, related to traffic and industrial emissions, photochemistry, and HNO3:NH4NO3 partitioning. While HNO3 concentrations were seen to peak in the summer in eastern and southern Europe (increased photochemistry), the absence of a spring peak in HNO3 in all regions may be explained by the depletion of HNO3 through reaction with surplus NH3 to form the semi-volatile aerosol NH4NO3. Cooler, wetter conditions in early spring favour the formation and persistence of NH4NO3 in the aerosol phase, consistent with the higher springtime concentrations of NH4+ and NO3-. The seasonal profile of NO3- was mirrored by NH4+, illustrating the influence of gas–aerosol partitioning of NH4NO3 in the seasonality of these components. Gas-phase NH3 and aerosol NH4NO3 were the dominant species in the total inorganic gas and aerosol species measured in the NEU network. With the current and projected trends in SO2, NOx, and NH3 emissions, concentrations of NH3 and NH4NO3 can be expected to continue to dominate the inorganic pollution load over the next decades, especially NH3, which is linked to substantial exceedances of ecological thresholds across Europe. The shift from (NH4)2SO4 to an atmosphere more abundant in NH4NO3 is expected to maintain a larger fraction of reactive N in the gas phase by partitioning to NH3 and HNO3 in warm weather, while NH4NO3 continues to contribute to exceedances of air quality limits for PM2.5.

A comprehensive European dataset on monthly atmospheric NH3, acid gases (HNO3, SO2, HCl) and aerosols (NH4+, NO3-, SO42-, Cl-, Na+, Ca2+, Mg2+) is presented and analyzed. Speciated measurements were made with a low-volume denuder and filter pack method (DELTA®) as part of the EU NitroEurope (NEU) integrated project. Altogether, there were 64 sites in 20 countries (2006–2010), coordinated between 7 European laboratories. Bulk wet deposition measurements were carried out at 16 co-located sites (2008–2010). Inter-comparisons of chemical analysis and DELTA® measurements allowed an assessment of comparability between laboratories. The form and concentrations of the different gas and aerosol components measured varied between individual sites and grouped sites according to country, European regions and 4 main ecosystem types (crops, grassland, forests and semi-natural). Smallest concentrations (with the exception of SO42- and Na+) were in Northern Europe (Scandinavia), with broad elevations of all components across other regions. SO2 concentrations were highest in Central and Eastern Europe with larger SO2 emissions, but particulate SO42- concentrations were more homogeneous between regions. Gas-phase NH3 was the most abundant single measured component at the majority of sites, with the largest variability in concentrations across the network. The largest concentrations of NH3, NH4+ and NO3- were at cropland sites in intensively managed agricultural areas (e.g. Borgo Cioffi in Italy), and smallest at remote semi-natural and forest sites (e.g. Lompolojänkkä, Finland), highlighting the potential for NH3 to drive the formation of both NH4+ and NO3- aerosol. In the aerosol phase, NH4+ was highly correlated with both NO3- and SO42-, with a near 1 : 1 relationship between the equivalent concentrations of NH4+ and sum (NO3- + SO42-), of which around 60 % was as NH4NO3. Distinct seasonality were also observed in the data, influenced by changes in emissions, chemical interactions and the influence of meteorology on partitioning between the main inorganic gases and aerosol species. Springtime maxima in NH3 were attributed to the main period of manure spreading, while the peak in summer and trough in winter were linked to the influence of temperature and rainfall on emissions, deposition and gas-aerosol phase equilibrium. Seasonality in SO2 were mainly driven by emissions (combustion), with concentrations peaking in winter, except in Southern Europe where the peak occurred in summer. Particulate SO42- showed large peaks in concentrations in summer in Southern and Eastern Europe, contrasting with much smaller peaks occurring in early spring in other regions. The peaks in particulate SO42- coincided with peaks in NH3 concentrations, attributed to the formation of the stable (NH4)2SO4. HNO3 concentrations were more complex, related to traffic and industrial emissions, photochemistry and HNO3 : NH4NO3 partitioning. While HNO3 concentrations were seen to peak in the summer in Eastern and Southern Europe (increased photochemistry), the absence of a spring peak in HNO3 in all regions may be explained by the depletion of HNO3 through reaction with surplus NH3 to form the semi-volatile aerosol NH4NO3. Cooler, wetter conditions in early spring favour the formation and persistence of NH4NO3 in the aerosol phase, consistent with the higher springtime concentrations of NH4+ and NO3-. The seasonal profile of NO3- was mirrored by NH4+, illustrating the influence of gas : aerosol partitioning of NH4NO3 in the seasonality of these components. Gas-phase NH3 and aerosol NH4NO3 were the dominant species in the total inorganic gas and aerosol species measured in the NEU network. With the current and projected trends in SO2, NOx and NH3 emissions, concentrations of NH3 and NH4NO3 can be expected to continue to dominate the inorganic pollution load over the next decades, especially NH3 which is linked to substantial exceedances of ecological thresholds across Europe. The shift from (NH4)2SO4 to an atmosphere more abundant in NH4NO3 is expected to maintain a larger fraction of reactive N in the gas phase by partitioning to NH3 and HNO3 in warm weather, while NH4NO3 continues to contribute to exceedances of air quality limits for PM2.5.

The UK Acid Gases and Aerosol Monitoring Network (AGANet) was established in 1999 (12 sites, increased to 30 sites from 2006), to provide long-term national monitoring of acid gases (HNO3, SO2, HCl) and aerosol components (NO3−, SO42−, Cl−, Na+, Ca2+, Mg2+). An extension of a low-cost denuder-filter pack system (DELTA) that is used to measure NH3 and NH4+ in the UK National Ammonia Monitoring Network (NAMN) provides additional monthly speciated measurements for the AGANet. A comparison of the monthly DELTA measurement with averaged daily results from an annular denuder system showed close agreement, while the sum of HNO3 and NO3− and the sum of NH3 and NH4+ from the DELTA are also consistent with previous filter pack determination of total inorganic nitrogen and total inorganic ammonium, respectively. With the exception of SO2 and SO42−, the AGANet provides, for the first time, the UK concentration fields and seasonal cycles for each of the other measured species. The largest concentrations of HNO3, SO2, and aerosol NO3− and SO42− are found in southern and eastern England and smallest in western Scotland and Northern Ireland, whereas HCl are highest in south-eastern, south-western, and central England, that may be attributed to dual contribution from anthropogenic (coal combustion) and marine sources (reaction of sea salt with acid gases to form HCl). Na+ and Cl− are spatially correlated, with largest concentrations at coastal sites, reflecting a contribution from sea salt. Temporally, peak concentrations in HNO3 occurred in late winter and early spring attributed to photochemical processes. NO3− and SO42− have a spring maxima that coincides with the peak in concentrations of NH3 and NH4+, and are therefore likely attributable to formation of NH4NO3 and (NH4)2SO4 from reaction with higher concentrations of NH3 in spring. By contrast, peak concentrations of SO2, Na+, and Cl− during winter are consistent with combustion sources for SO2 and marine sources in winter for sea salt aerosol. Key pollutant events were captured by the AGANet. In 2003, a spring episode with elevated concentrations of HNO3 and NO3− was driven by meteorology and transboundary transport of NH4NO3 from Europe. A second, but smaller episode occurred in September 2014, with elevated concentrations of SO2, HNO3, SO42−, NO3−, and NH4+ that was shown to be from the Icelandic Holuhraun volcanic eruptions. Since 1999, AGANet has shown substantial decrease in SO2 concentrations relative to HNO3 and NH3, consistent with estimated decline in UK emissions. At the same time, large reductions and changes in the aerosol components provide evidence of a shift in the particulate phase from (NH4)2SO4 to NH4NO3. The potential for NH4NO3 to release NH3 and HNO3 in warm weather, together with the surfeit of NH3 also means that a larger fraction of the reduced and oxidized N is remaining in the gas phase as NH3 and HNO3 as indicated by the increasing trend in ratios of NH3 : NH4+ and HNO3 : NO3− over the 16-year period. Due to different removal rates of the component species by wet and dry deposition, this change is expected to affect spatial patterns of pollutant deposition with consequences for sensitive habitats with exceedance of critical loads of acidity and eutrophication. The changes are also relevant for human health effects assessment, particularly in urban areas as NH4NO3 constitutes a significant fraction of fine particulate matter (

Rainfall chemistry networks inevitably report some missing data, caused by contamination or loss of samples. However, there are no universally accepted rules about how such data, particularly from samples contaminated in the field, are identified and reported, leading to uncertainties in data usage by third parties, and possible incorrect inferences based on the reported data. This paper describes how the UK rainfall chemistry network data have been analysed for contamination, and how missing values can be estimated based on cross-correlations in time and space, using data from 20 sites over 26 years. The final flagged dataset is available through the CEH Environmental Information Data Centre (EIDC). Erroneous data values are identified through consideration of ion balance (internal consistency), and evidence of contamination by birds or windblown dust based on the reported chemical analysis. Overall data capture with the erroneous data excluded and no replacement of missing data was 86%, but with much smaller data capture at some sites in some years, to less than 30% in some cases. The use of estimated data to replace missing values resulted in an increase in overall data capture to 96%, with only one site having data capture less than 70% in an individual year, and all sites achieving a data capture of 88% or more over the full period. The implications of using the reported ‘official’ annual data, as opposed to the dataset with missing values replaced by estimates, are illustrated by consideration of the temporal trend in nitrate at one site, which shows twice the value in the ‘official’ reported annual data compared with the ‘estimated’ data, part of a consistent pattern across all sites. Use of the uncorrected ‘raw’ sample data leads to large errors.

Wet deposition of nitrogen (N) occurs in oxidized (nitrate) and reduced (ammonium) forms. Whether one form drives vegetation change more than the other is widely debated, as field evidence has been lacking. We are manipulating N form in wet deposition to an ombrotrophic bog, Whim (Scottish Borders), and here report nine years of results. Ammonium and nitrate were provided in rainwater spray as NH4 Cl or NaNO3 at 8, 24 or 56 kg N ha(-1) yr(-1) , plus a rainwater only control, via an automated system coupled to site meteorology. Detrimental N effects were observed in sensitive nonvascular plant species, with higher cumulative N loads leading to more damage at lower annual doses. Cover responses to N addition, both in relation to form and dose, were species specific and mostly dependent on N dose. Some species were generally indifferent to N form and dose, while others were dose sensitive. Calluna vulgaris showed a preference for higher N doses as ammonium N and Hypnum jutlandicum for nitrate N. However, after 9 years, the magnitude of change from wet deposited N on overall species cover is small, indicating only a slow decline in key species. Nitrogen treatment effects on soil N availability were likewise small and rarely correlated with species cover. Ammonium caused most N accumulation and damage to sensitive species at lower N loads, but toxic effects also occurred with nitrate. However, because different species respond differently to N form, setting of ecosystem level critical loads by N form is challenging. We recommend implementing the lowest value of the critical load range where communities include sensitive nonvascular plants and where ammonium dominates wet deposition chemistry. In the context of parallel assessment at the same site, N treatments for wet deposition showed overall much smaller effects than corresponding inputs of dry deposition as ammonia.

An experiment was carried out to compare the digestibility and nitrogen balance of local Red Chittagong (RC) and Holstein cross (Hx) cattle with high- and low-quality forages supplemented with high- and low-quality protein concentrates. The diets were high digestibility German grass with high-protein soybean meal (SBM) (A), high digestibility German grass with low-protein wheat bran (WB) (B), low digestibility rice straw with high-protein SBM (C) and low digestibility rice straw with low-protein WB (D). Each breed was offered the treatments in a 4×4 Latin square design. The RC steer has a significantly higher digestibility of all proximate components (except NFE) than Hx. Weight gain and N-balance were same in both of the breeds. High digestibility and high-protein diets showed better results in respect of the digestibility, weight gain and N-balance and the worst result from low digestibility and low protein. The low digestibility and low-protein diet also showed positive weight gain and N-balance. No si...

Science-based approaches in addressing future risks and challenges for forests require close collaboration among the communities operating different monitoring and research networks as well as experts in process and large-scale modelling. Results of the COST FP0903 conference which took place in October 2010 in Rome, reveal valuable results from different European forest monitoring and research networks. However, the need for closer integration of these activities is obvious. In this paper, representatives from major European networks recommend a new approach for forest monitoring and research in Europe, based on a reasonable number of highly instrumented “supersites” and a larger number of intensive monitoring plots linked to these. This system needs to be built on existing infrastructures but requires increased coordination, harmonisation and a joint long term platform for data exchange and modelling.

Set against the backdrop of the historical shift from modernity into postmodernity, this article explores the growing importance of music destination tourism for the baby boomer generation in their quest for personal and social meaning. The study is multidisciplinary in nature, drawing on writings on music tourism, consumer behaviour, sociology and various strands of the marketing literature. The focus of the study is the marketing of music heritage sites associated with a range of artists representative of the rock genre, namely Buddy Holly, Elvis Presley, Bob Dylan and The Beatles. Findings draw on field visits consisting of participant observation and key informant interviews with stakeholders representing both commercial and not-forprofit organizations. They illustrate the iconic, even quasi-religious, nature of the representation of these artists through the staging of the sites, highlighting the importance of nostalgia, authenticity and sensitivity to the naturalistic nature of the experienc...

PurposeThe purpose of this paper is to investigate the nature of music‐based tourism in the context of the childhood locations of music icons from the 1950s and 1960s. The Beatles, Bob Dylan, Buddy Holly and Elvis Presley are selected and fieldwork is carried out in Hibbing, Liverpool, Lubbock, Memphis and Tupelo.Design/methodology/approachA normative approach is chosen using existing work on music‐based tourism as a backdrop. Key informant interviews are the main sources of primary data with a snowball technique used to gain access. Content and theme analysis is used.FindingsMusic‐based tourism is emotion driven with ideas of pilgrimage, nostalgia and heritage centring on sites of production of music; birth and death of individual artists; and places which shaped their early history. The demographic base of this market segment is widening to include both “baby‐boomers” and younger visitors for whom these music icons have become part of pop culture. It is important to recognise the sensitivities of these visitors and authenticity is a key factor.Originality/valueThis study is of interest to managers involved in promoting tourism and the marketing of place. It provides detail from major cities such as Liverpool to small towns such as Hibbing, Minnesota with a population of 18,000.

The UK's independent food and grocery retail sector's competitive advantage of 'convenience' has been eroded in recent years as major retailers increase opening hours and develop their own convenience trading formats. As a result, large numbers of independent retailers are closing. A UK-wide survey was undertaken to identify other sources of competitive advantages, and the changes needed to stop or reverse the decline in this sector. Exploratory semi-structured interviews led to the development of a questionnaire on six major issues affecting the sector. 'Snowball' sampling, using industry partners, provided 142 respondents. The provision of a 'social shopping experience' emerged as a key competitive advantage that could be developed. Improving vertical and horizontal trading alliances, and the wider use of information technology, provided other options.

Se evaluó la dinámica degradativa de forrajes, en muestras de una pradera permanente (Lolium perenne L.), manejadas a dos alturas de pradera, alta y baja. Las muestras consistieron en forraje disponible a ras de suelo (FD) y en forraje aparentemente consumido por vacas lecheras en pastoreo continuo (FS). La degradabilidad ruminal se estudió usando la técnica de las bolsas de dacrón y los datos fueron ajustados a una ecuación exponencial. La fracción soluble (g/kg MS), de la materia seca (MS) (299 v/s 351, s.e.d.= 5,4), de la materia organica (MO) (304 v/s 376, s.e.d.= 3,3) y del nitrógeno (250 v/s 301, s.e.d.= 6,4), fueron significativamente mayores (P

Explains that UK consumers currently spend over £9 billion on do‐it‐yourself (DIY) home improvement products. States that in the 1980s this was the UK’s fastest growing major retail sector, and the booming UK housing market, especially the number of house moves, was widely thought to be the main stimulus for this growth. Reveals that the annual number of house moves has fallen by 50 per cent since 1988 but the DIY market has still grown, which suggests that the link between DIY and the housing market has either changed or is not as strong as previously believed. Reassesses the major factors which affected the DIY market in the 1980s through data analysis and multiple regression techniques. Suggests from the results that the effect of house moves on the DIY market is less than conventional wisdom would indicate. Notes that the most significant factors have been identified and are being used in a five‐year forecast which shows growth in line with increases in the general economy in a new, mature DIY market. Concludes that the results highlight the care needed when basing forecasts on a single factor which may no longer be valid.

Total gaseous mercury was collected at ten sites, which comprise part of the UK rural heavy metals monitoring network, between 2005 and 2008. Using the gold amalgam technique to capture total gaseous mercury, samples were analysed using a Tekran 2537A mercury vapour analyser. The data showed no upward or downward trend in atmospheric mercury concentrations over the period, with 4 year average concentrations between 1.3 and 1.9 ng m(-3), which are in line with other studies' observed northern hemispheric background concentrations of between 1.5 and 1.7 ng m(-3). Using data from nine of the sites, we were able to show seasonality within the data and through kriging we were able to interpolate the TGM concentrations over the UK, revealing a south-east to north-west declining concentration gradient. Using continuous speciated mercury measurements from one of the network sites, we show through wind sector analysis and air-mass back trajectories that this spatial trend is likely to be due to air masses moving over the UK from continental Europe on easterly winds. The levels of TGM recorded in the south-east of the UK also more closely match observed background TGM levels on the continent, which could indicate that the TGM concentrations from the north of the UK are a better reflection of the true North Atlantic atmospheric mercury background level.

In difficult retail trading conditions, and as price‐led strategies become more common, cost control is a very high priority for retailers. The problem faced by UK retailers is that many of the factors influencing the rising trend of consumer theft are outside their control. Identifies some of the social and political factors involved. Based on interviews with retailers a general security strategy of containing consumer theft and actively driving down other “unaccounted” stock losses emerged. However, within this general strategy each retailer adapted it to their particular needs and capabilities.

List of Maps Special Features Foreword Changes to the Third Edition Preface About the Authors Part I: Africa Up To 1500 C.E. Chapter 1: Physical Context of African History: Geography and Environment Physical Features of the Continent Challenges of the African Environment The African Environment in Global Perspective Chapter 2: Africa and Human Origins Early Perspectives on Human Origins and the Notion of Race Africa and Human Origins in Global Perspective Chapter 3: Finding Food and Talking About It: The First 100,000 Years Humans and the Environment: Foraging for Food Regional Foraging Strategies The African Environment and the First Modern Humans in Global Perspective Chapter 4: Settled Life: Food Production, Technology, and Migrations The Origins of Food Production Animal Domestication The Social, Political, and Economic Impact of Food Production The Bantu Expansion Metallurgy and the Banana Political and Religious Culture in Early African History Early African Migrations, Technology, and Culture in Global Perspective Chapter 5: North and Northeast Africa in Early World History Egypt in Early World History Ancient Egypt and Greece Carthage and Rome in Early Northern Africa Ancient Nubia and the Horn of Africa in the Ancient World Ancient Africa United: The Afrocentric Argument Ancient North and Northeastern Africa in Global Perspective Chapter 6: Africa and the Early Christian World The Spread of Christianity in Africa African Contributions to Early Christian Thought The Decline of African Christianity Early African Christianity in Global Perspective Chapter 7: North and West Africa and the Spread of Islam The Origins of Islam Islam in North Africa Empires, Trade, and Islam in the West African Savannah The Rise of Mali The Rise of Songhai Islam in Kanem-Bornu and Hausaland African Traditional Religions and Conversion The Africanization of Islam Islam in North and West Africa in Global Perspective Chapter 8: East Africa and the Advent of Islam The Monsoons Swahili Origins Islam and the Emergence of the Swahili as a Distinctive Group Life in the Early Swahili Towns: 750-1000 The High Point of Swahili Civilization: 1000-1500 Urban Transformation Economic Transformation Kilwa: A Case Study The Swahili Coast in Global Perspective Part II: Africa Since 1500 C.E. Chapter 9: Slavery and the Creation of the Atlantic World The Institution of Slavery before the Rise of the Atlantic Trade Slavery in the Mediterranean and Europe Slavery in Africa The Institution of Slavery The Birth of the Plantation Complex New Sea Routes The Plantation System in the New World Race and Slavery in the New World The Nature of the Slave Trade Shipboard Conditions The Human Toll Justifications for the Slave Trade Counting the Cost African Culture in Diaspora African Religion in the New World Independent African Communities in the New World Diasporic Africans Back in Africa-Routes of Return The Atlantic System and Economic Change The Atlantic System and the Industrial Revolution The Atlantic System and African Poverty Abolition of the Slave Trade The End of the Atlantic World The Atlantic Slave Trade in Global Perspective Chapter 10: West and West-Central Africa: 1500-1880 The Setting: West and West-Central Africa Prior to European Contact First Impressions Early Relations-Religion, Trade, and Politics Africa Transformed? Africa and the Atlantic Slave Trade Regional Developments in the Era of the Slave Trade The End of the Slave Trade and the Rise of Legitimate Trade West and West-Central Africa 1500-1880, in Global Perspective Chapter 11: North Africa and the Soudan: 1500-1880 The Ottomans in Egypt The Ottomans in the Maghreb Ottoman Culture in North Africa The Rise of Morocco Invasion and Reform in Egypt French Invasion in Algeria Religious Change in the Soudan to the 1880s North Africa and the Soudan, 1500-1880, in Global Perspective Chapter 12: East Africa, 1500-1850 The Arrival of the Portuguese The Omani Empire in East Africa The Busaids Britain and the Suppression of the Indian Ocean Slave Trade Links to the Interior Portuguese and Omani Dominance in Global Perspective Chapter 13: Southern Africa, 1500-1870 Terrain, Climate, and Settlement Shaka and the Rise of the Zulu State Mzilikazi and the "Ndebele" Moshoeshoe The "Voortrekkers" The British Expansion and the Formation of the Boer Republics South Africa in Global Perspective, 1500-1870 Chapter 14: Colonialism and African Resistance Europe's Industrial Transformation and Africa Quinine and Colonialism Weapons and Colonialism The Great Transformation The Limits of Resistance The Colonization of a Continent The Expansion of the Gold Coast Colony Creating the Belgian Congo Ethiopia: Where European Imperialism Failed African Colonization in Global Perspective Chapter 15: Economic Change in Modern Africa: Forced Integration into the World System The Cash Crop Revolution Colonial Transportation Networks Cocoa Farming in Ghana Cotton and Groundnuts in Nigeria Africans as Wage Laborers Slavery and Labor in Zanzibar Settlers in the Kenya Highlands The Cities of Africa Women and Work in Colonial Africa The Movement to Independence and Modernization African Economic History in Global Perspective Chapter 16: Political Change in the Time of Colonialism Varieties of Colonial Administration World War I and Colonial Rule Colonialism and African "Elites" World War II and the Twilight of Colonial Rule Colonial Rule in Africa in Global Perspective Chapter 17: African Culture in the Modern World Africa and Anthropology Christianity and Colonialism Independent Churches Islam as a Globalizing Force Migrants and Mobility Soccer on the Global Stage Movies and Music Modern African Culture in Global Perspective Chapter 18: Politics in the Era of Decolonization and Independence The Era of Decolonization The Rise of African Nationalist Movements Decolonization in the Settler States and Portuguese Africa After Colonialism: Independence1/4or into Dependence? Pan-Africanism The Challenges of Independence The Congo Crisis Political Change in Independent Africa: Innovation or Regression? Independent African States in Global Perspective Chapter 19: Contemporary Africa The End of the Cold War and Political Change in Africa The End of Apartheid Conflict and Collapsed States in the Post-Cold War Era Africa and the War on Terror The Rwandan Genocide and the "African World War" Genocide in Sudan? Globalization and Development in Contemporary Africa The HIV Pandemic and Africa African Solutions Contemporary Africa in Global Perspective-Looking Back, Looking Ahead Glossary Selected Bibliography Credits Index

In a double blind cross over trial of oral practolol the total work performed before anginal pain was increased by 30 per cent when patients were taking 400 mg/day and by 40 per cent when patients were taking 800 mg/day. The heart rate at which anginal pain occurred during effort was approximately 15 per cent lower during practolol treatment than during placebo treatment. Electrocardiographic changes of ischemia were less severe during practolol treatment than during placebo treatment at all exercise levels up to and including the onset of pain. Practolol is an effective drug in the prophylaxis of angina pectoris and has been previously shown to be less depressant than propranolol in patients with poor myocardial function. It should nevertheless be used with caution, and a suggested clinical regimen is outlined.

Twenty patients with severe ischaemic heart-disease were assessed before and at least 10 months after a revascularisation procedure. They were placed into four grades according to clinical severity. The assessment consisted of clinical examination with special attention to the signs of left ventricular dysfunction, electrocardiogram, chest X-ray, and selective coronary angiography. An objective assessment was obtained by an atrial pacing test. The operation consisted of bilateral internal mammary-artery implantation in seventeen patients and unilateral in three. Five of them had some additional procedure done. The assessment was repeated after operation with internal-mammary angiography in place of coronary angiography. Seventeen patients survived more than one year and twelve of these (71%) were subjectively improved. They represent 60% of the original group. The objective assessment by atrial pacing correlated with the clinical results. Angiographic evidence of communication of the implanted vessel with the coronary-artery tree was demonstrated in only three patients and 13 of the 18 vessels assessed were occluded. There was thus no correlation between angiographic findings and clinical results.